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Sample records for acute organophosphorus insecticide

  1. Organophosphorus Insecticide Pharmacokinetics

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Charles

    2010-01-01

    This chapter highlights a number of current and future applications of pharmacokinetics to assess organophosphate (OP) insecticide dosimetry, biological response and risk in humans exposed to these agents. Organophosphates represent a large family of pesticides where insecticidal as well as toxicological mode of action is associated with their ability to target and inhibit acetylcholinesterase (AChE). Pharmacokinetics entails the quantitative integration of physiological and metabolic processes associated with the absorption, distribution, metabolism and excretion (ADME) of drugs and xenobiotics. Pharmacokinetic studies provide important data on the amount of toxicant delivered to a target site as well as species-, age-, gender-specific and dose-dependent differences in biological response. These studies have been conducted with organophosphorus insecticides in multiple species, at various dose levels, and across different routes of exposure to understand their in vivo pharmacokinetics and how they contribute to the observed toxicological response. To access human exposure to organophosphorus insecticides, human pharmacokinetic studies have been conducted and used to develop biological monitoring strategies based on the quantitation of key metabolites in biological fluids. Pharmacokinetic studies with these insecticides are also useful to facilitate extrapolation of dosimetry and biological response from animals to humans and for the assessment of human health risk. In this regard, physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) models are being utilized to assess risk and understand the toxicological implications of known or suspected exposures to various insecticides. In this chapter a number of examples are presented that illustrate the utility and limitation of pharmacokinetic studies to address human health concerns associated with organophosphorus insecticides.

  2. Pralidoxime in acute organophosphorus insecticide poisoning--a randomised controlled trial.

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    Michael Eddleston

    2009-06-01

    Full Text Available BACKGROUND: Poisoning with organophosphorus (OP insecticides is a major global public health problem, causing an estimated 200,000 deaths each year. Although the World Health Organization recommends use of pralidoxime, this antidote's effectiveness remains unclear. We aimed to determine whether the addition of pralidoxime chloride to atropine and supportive care offers benefit. METHODS AND FINDINGS: We performed a double-blind randomised placebo-controlled trial of pralidoxime chloride (2 g loading dose over 20 min, followed by a constant infusion of 0.5 g/h for up to 7 d versus saline in patients with organophosphorus insecticide self-poisoning. Mortality was the primary outcome; secondary outcomes included intubation, duration of intubation, and time to death. We measured baseline markers of exposure and pharmacodynamic markers of response to aid interpretation of clinical outcomes. Two hundred thirty-five patients were randomised to receive pralidoxime (121 or saline placebo (114. Pralidoxime produced substantial and moderate red cell acetylcholinesterase reactivation in patients poisoned by diethyl and dimethyl compounds, respectively. Mortality was nonsignificantly higher in patients receiving pralidoxime: 30/121 (24.8% receiving pralidoxime died, compared with 18/114 (15.8% receiving placebo (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 0.88-3.26, p = 0.12. Incorporating the baseline amount of acetylcholinesterase already aged and plasma OP concentration into the analysis increased the HR for patients receiving pralidoxime compared to placebo, further decreasing the likelihood that pralidoxime is beneficial. The need for intubation was similar in both groups (pralidoxime 26/121 [21.5%], placebo 24/114 [21.1%], adjusted HR 1.27 [95% CI 0.71-2.29]. To reduce confounding due to ingestion of different insecticides, we further analysed patients with confirmed chlorpyrifos or dimethoate poisoning alone, finding no evidence of

  3. Zebrafish Models for Human Acute Organophosphorus Poisoning.

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    Faria, Melissa; Garcia-Reyero, Natàlia; Padrós, Francesc; Babin, Patrick J; Sebastián, David; Cachot, Jérôme; Prats, Eva; Arick Ii, Mark; Rial, Eduardo; Knoll-Gellida, Anja; Mathieu, Guilaine; Le Bihanic, Florane; Escalon, B Lynn; Zorzano, Antonio; Soares, Amadeu M V M; Raldúa, Demetrio

    2015-10-22

    Terrorist use of organophosphorus-based nerve agents and toxic industrial chemicals against civilian populations constitutes a real threat, as demonstrated by the terrorist attacks in Japan in the 1990 s or, even more recently, in the Syrian civil war. Thus, development of more effective countermeasures against acute organophosphorus poisoning is urgently needed. Here, we have generated and validated zebrafish models for mild, moderate and severe acute organophosphorus poisoning by exposing zebrafish larvae to different concentrations of the prototypic organophosphorus compound chlorpyrifos-oxon. Our results show that zebrafish models mimic most of the pathophysiological mechanisms behind this toxidrome in humans, including acetylcholinesterase inhibition, N-methyl-D-aspartate receptor activation, and calcium dysregulation as well as inflammatory and immune responses. The suitability of the zebrafish larvae to in vivo high-throughput screenings of small molecule libraries makes these models a valuable tool for identifying new drugs for multifunctional drug therapy against acute organophosphorus poisoning.

  4. Toxicological Properties of the Organophosphorus Insecticide Dimethoate

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    Sanderson, D. M.; Edson, E. F.

    1964-01-01

    The results are presented of extensive toxicological studies on the systemic organophosphate insecticide dimethoate, and compared with published results from other laboratories. It behaves as a typical indirect anticholinesterase, by conversion in the liver to at least four short-lived active metabolites, whose hydrolysis products are rapidly excreted, mainly in the urine. The acute oral toxicity of dimethoate is low in mammals but higher in avians. Dermal absorption is notably slow and dermal toxicity correspondingly low. Cumulative dosing of rats and guinea-pigs gave no cholinesterase inhibition at 0·7 and 4 mg./kg./day respectively. Dietary feeding to growing rats caused no cholinesterase inhibition at 0·5 mg./kg./day and no other effect at 10 times this dose. The main plant metabolite is identical with one formed in the liver, and comparative feeding tests with normal dimethoate and that partly metabolized in vegetation showed that residue analysis determined total hazard. Tests on humans, some with 32P-labelled material, confirmed that metabolism and urinary excretion are very rapid, that skin absorption is very slow, and that at least 2·5 mg., and probably up to 18 mg., could be ingested daily for at least three weeks without cholinesterase inhibition or other effects. Vapour hazards proved negligible. Oral toxicity was not potentiated by any of 17 other insecticides. The earliest detectable effect of dimethoate poisoning was always erythrocyte cholinesterase inhibition. Symptoms of poisoning could be effectively treated by atropine but not by oxime therapy. No known cases of occupational poisoning have occurred during five years' commercial usage of dimethoate. PMID:14106136

  5. Development of the Artificial Antigens for the Organophosphorus Insecticide chlorpyrifos

    Institute of Scientific and Technical Information of China (English)

    ZHU Guo-nian; WU Gang; WU Hui-ming

    2004-01-01

    This study reported that the hapten of the organophosphorus insecticide chlorpyrifos,O,Odiethyl-O-[3,5-dichloro-6-(2-carboxyethyl)thio-2-pyridyl]phosphorothioate(named AR) was synthesized by using technical grade chlorpyrifos reacted with 3-marcapropanoic acid in hot alkaline solution.The hapten was conjugated to bovine serum albumin (BSA) with the modified active ester method to form artificial immune antigen.The ratio of AR:BSA was 39:1.The artificial coating antigen for chlorpyrifos was synthesized by conjugating AR to ovalbumin (OVA) with the mixed-anhydride method,and the ratio was 13:1.The anti-chlorpyrifos polyclonal antibodies were obtained by using the artificial immune antigen (AR-BSA) to immune in the rabbits.

  6. Effect of organophosphorus insecticides on phosphorylation of the M2 muscarinic acetylcholine receptor

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    Shuyin Li; Liming Zou; Carry Pope

    2008-01-01

    BACKGROUND: Organophosphorus insecticides may promote the accumulation of acetylcholine at synapses and the neuromuscular junction by inhibiting acetylcholinesterase activity to cause disturbance of neural signal conduction and induce a toxic reaction. Organophosphorus insecticides may act on M2 muscarinic acetylcholine receptors, whose combination with G proteins is regulated by phosphorylation of G protein-coupled receptor kinase 2.OBJECTIVE: To investigate the effects of organophosphorus insecticides on the phosphorylation of G protein-coupled receptor kinase 2-mediated M2 muscarinic acetylcholine receptors and to reveal other possible actions of organophosphorus insecticides.DESIGN, TIME AND SETTING: An observational study, which was performed in the Central Laboratory of Shenyang Medical College, and Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University from June 2002 to December 2004.METHODS: The M2 muscarinic acetylcholine receptor was extracted and purified from pig brain using affinity chromatography. Subsequently, the purified M2 muscarinic acetylcholine receptor, G protein-coupled receptor kinase 2, and [OP32] ATP were incubated with different concentrations of paraoxon and chlorpyrifos oxon together. The mixture then underwent polyacrylamide gel electrophoresis, and the gel film was dried and radioactively autographed to detect phosphorylation of the M2 muscarinic acetylcholine receptor. Finally, the radio-labeled phosphorylated M2 receptor protein band was excised for counting with an isotope liquid scintillation counter.MAIN OUTCOME MEASURES: Effects of chlorpyrifos oxon, paraoxon, chlorpyrifos, and parathion in different concentrations on the phosphorylation of the M2 muscarinic acetylcholine receptor; effects of chlorpyrifos oxon on the phosphorylation of the adrenergic receptor.CONCLUSION: Different kinds of organophosphorus insecticides have different effects on the phosphorylation of the G protein

  7. 应用APACHE Ⅱ评分对急性有机磷农药中毒患者氯解磷定总用量估模的临床研究%Reseach on Application of Estimation Model about Total Amount of Pralidoxime Chloride with APACHE Ⅱ on Treatment of Acute Organophosphorus Insecticide Poisoning Patients

    Institute of Scientific and Technical Information of China (English)

    罗静; 辜小丹

    2011-01-01

    Objective: The patents of acute organophosphorus insecticide poisoning were treated with the cure project of estimation value of the total dosage of pralidoxime chloride (PAM.Cl). Methods: 91 cases of patents of acute organophosphorus insecticide poisoning were treated. When their sate of illness was the most serious, the scores (X) of the acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ)were substituted in (Y) =-43.4+4.7X in the first 24 hours, the total dosage (Y) of PAM.Cl was calculated. The method of large quantity concentrated dose was used until clinical cure was achieved in order to prove the above formula. Results: The process of cure of the patents of acute organophosphorus insecticide poisoning indicated that the actual total dosage of used pralidoxime chloride corresponded to the estimation value of the total dosage of used pralidoxime chloride. Conclusinon: The total dosage of pralidoxime chloride of highly toxic type organophosphorus insecticide poisoning patents that was initially estimated by the APACHE Ⅱ score was accurate. The formula Y=-43.4+4.7X is an effective method that directs the total dosage of pralidoxime chloride of highly toxic type organophosphorus insecticide poisoning, it is of benefit to direct dosage.%目的:对有机磷农药急性中毒患者应用氯解磷定总用量估模值的救治方案进行治疗,观察其疗效.方法:对91例重度急性有机磷农药中毒(AOPP)患者就行救治,取中毒后第一个24小时内,病情最严重时的急性生理学与慢性健康状况评分Ⅱ(APACHE Ⅱ)的分值(X),代入Y=-43.4+4.7X,计算出PAM.C1总用量(Y),并按大量突击疗法应用至临床治愈,验证上述公式.结果:急性有机磷农药中毒患者的救治过程表明,氯解磷定实际总用量与总用量估模值一致.结论:通过APACHE Ⅱ评分系统初步估模出急性有机磷农药中毒患者氯解磷定总用量的值,是准确的.公式Y=-43.4+4.7X是指导急性有机磷农药中毒

  8. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

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    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  9. Biochemical Markers for Exposure to Low Doses of Organophosphorus Insecticides

    Science.gov (United States)

    2005-08-01

    Schopfer Environ Toxicol Pharmacol (2005) 19: 463-469 Abstract The acetylcholinesterase (AChE) knockout mouse is a new tool for identifying physiologically ...Abiteboul M, Siest G and Netter P (1995) Stereoselective esterase activity of human serum albumin toward ketoprofen glucuronide. Mol Pharmacol 47:647-653...identifying physiologically relevant targets of organophosphorus toxicants (OP). If AChE were the only important target for OP toxicity, then mice

  10. Effect of quinalphos, organophosphorus insecticide, on testicular steroidogenesis in fish, Clarias batrachus

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    Bagchi, P.; Chatterjee, S.; Ray, A.; Deb, C. (Univ. College of Science and Technology, Calcutta (India))

    1990-06-01

    The presence of insecticides in the environment, due to extensive use in agriculture and their low degradation capacity, are of potential toxicological concern for fish. Insecticides have also been found to be highly toxic not only to fish, but also to organisms which constitute the food of fish. Catfish, particularly the airbreathing species, are attracting attention of the pisciculturists owing to their high production potential from paddy fields and stagnant shallow ponds. In an earlier study the authors have shown that quinalphos, a widely used insecticide of organophosphorus group in the field of agriculture, has inhibitory effects on the steroidogenic status of testes in rats. Keeping this in view, an experiment has been conducted with the insecticide quinalphos to study the effects on steroidogenic activity of testes of a dietary catfish, Magur (Clarias batrachus).

  11. Relationship between blood alcohol concentration on admission and outcome in dimethoate organophosphorus self-poisoning

    OpenAIRE

    Eddleston, Michael; Gunnell, David; von Meyer, Ludwig; Eyer, Peter

    2009-01-01

    center dot Acute alcohol intoxication often complicates acute organophosphorus pesticide poisoning.center dot No data are available on how alcohol intoxication affects outcome in acute organophosphorus pesticide poisoning.center dot In particular, the relationships between plasma alcohol concentration and plasma organophosphorus concentration or outcome are unclear.WHAT THIS STUDY ADDScenter dot Alcohol co-ingestion is associated with higher concentrations of the organophosphorus insecticide ...

  12. Case histories of bald eagles and other raptors killed by organophosphorus insecticides topically applied to livestock.

    Science.gov (United States)

    Henny, C J; Kolbe, E J; Hill, E F; Blus, L J

    1987-04-01

    Since 1982 when secondary poisoning of a red-tailed hawk (Buteo jamaicensis) was documented following the recommended use of famphur applied topically to cattle, the Patuxent Wildlife Research Center has tested dead birds of prey for poisoning by famphur and other pour-on organophosphorus (OP) insecticides. Brain cholinesterase (ChE) activity was first determined, then if ChE was depressed greater than or equal to 50%, stomach and/or crop contents were evaluated for anti-ChE compounds. This report presents the circumstances surrounding the OP-caused deaths of eight bald eagles (Haliaeetus leucocephalus), two red-tailed hawks, and one great horned owl (Bubo virginianus) between March 1984 and March 1985. OP poisoning of raptors by pour-on insecticides in the United States is widespread, but its magnitude is unknown.

  13. Case histories of bald eagles and other raptors killed by organophosphorus insecticides topically applied to livestock

    Science.gov (United States)

    Henny, C.J.; Kolbe, E.J.; Hill, E.F.; Blus, L.J.

    1987-01-01

    Since 1982 when secondary poisoning of a red-tailed hawk (Buteo jamaicensis) was documented following the recommended use of famphur applied topically to cattle, the Patuxent Wildlife Research Center has tested dead birds of prey for poisoning by famphur and other pour-on organophosphorus (OP) insecticides. Brain cholinesterase (ChE) activity was first determined, then if ChE was depressed greater than or equal to 50%, stomach and/or crop contents were evaluated for anti-ChE compounds. This report presents the circumstances surrounding the OP-caused deaths of eight bald eagles (Haliaeetus leucocephalus), two red-tailed hawks, and one great horned owl (Bubo virginianus) between March 1984 and March 1985. OP poisoning of raptors by pour-on insecticides in the United States is widespread, but its magnitude is unknown.

  14. Acute Toxicity of Four Organophosphorus Pesticide Products

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Acute toxicity of phoxim,acephate,isofenphos-methyl and isocarbophos on male SD rats of clean grade was carried out by gastric lavage method at room temperature of 18℃. These rats are 4 to 5 months old with body weight of 180 to 220 kg. The results indicate that the orders of the toxicity of these four pesticides on SD rats are isofenphos-methyl,isocarbophos,acephate,phoxim. We found that the median lethal concentration of phoxim in 24 h,48 h,72 h and 96 h is 3. 892 g /kg,3. 051 g /kg,2. 618 g /kg and 2. 458 g /kg respectively; the median lethal concentration of isofenphos-methyl in 24 h,48 h,72 h and 96 h is 0. 015 g /kg,0. 013g /kg,0. 012g /kg and 0. 011 g /kg respectively; the median lethal concentration of isocarbophos in 24 h,48 h,72 h and 96 h is 0. 049 g /kg,0. 046 g /kg,0. 043 g /kg,0. 041 g /kg respectively; and the median lethal concentration of acephate in 24 h,48 h,72 h and 96 h is 0. 137 g /kg,0. 113 g /kg,0. 100 g /kg,0. 085 g /kg respectively. Finally,we evaluated the characteristics of toxicity effect and safe concentration of these pesticides to SD rats.

  15. Crystal and molecular structures of some organophosphorus insecticides and computer methods for structure determination. [Dissertation

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    Lapp, R.L.

    1979-01-01

    Molecular structure investigations of a set of organophosphorus insecticides have been carried out in order to acquire the data base to develop correlations between such parameters and their toxicities. The crystal and molecular structures of dimethoate (LD/sub 50/ (rats) = 600 mg/kg), IPAT, and leptophos (LD/sub 50/ (rats) = 90 mg/kg) have been determined via three-dimensional x-ray analysis. The crystal and molecular structure of (-)-..cap alpha..-phenylethylammonium (-)-0-methyl-phenylphosphonothioate was solved by conventional Patterson and Fourier techniques to a final R value of 0.057. The crystal and molecular structures of two crystalline forms of calcium formate were determined. A new least-squares refinement program was written which is much more general and efficient than any previous program. In particular, a new block-diagonal approximation has been devised which is much more economical than full-matrix refinement and appears to work much better than previous block-diagonal methods. A Howells, Phillips and Rogers test for a center of symmetry and a Wilson plot have been programmed into the data collection algorithm. Some approximations and special problems are discussed relative to implementing these routines in a real-time mode on a minicomputer. A mathematical background and program description are included for each program.

  16. Evaluation of organophosphorus and synthetic pyrethroid insecticides against six vector mosquitoe species

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    Domingo Montada Dorta

    1993-12-01

    Full Text Available Three organophosphorus compounds- malathion, folithion and temephos- and two synthetic pyrethroids- alphamethrin and deltamethrin- were used for monitoring the susceptibility status of larvae and adults of six vector mosquitoe species: Culex quinquefasciatus (Filariasis and Aedes albopictus (Dengue (both laboratory and field strains; laboratory strains of Aedes aegypti (Dengue, Anopheles slephensi and Anopheles culicifacies (Malaria, and Culex tritaeniorhynchus (Japanese encephalitis in India. From the LC50 values obtained for these insecticides, it was found that all mosquito species including the field strains of Cx. quinquefasciatus and Ae. albopictus were highly susceptible Except for Cx. quinquefasciatus (field strain against malathion, 100% mortality was observed at the discriminating dosages recommended by World Health Organization. The residual effect of alphamethrin, deltamethrin, malathion and folithion at 25 mg (ai/m² on different surfaces against six species of vector mosquitoes showed that alphamethrin was the most effective on all four treated surfaces (mud, plywood, cement and thatch. Nevertheless, residual efficacy lasted longer on thatch than on the other surfaces. Therefore, synthetic pyrethroids such as alphamethrin can be effectively employed in integrated vector control operations.

  17. Evaluation of organophosphorus and synthetic pyrethroid insecticides against six vector mosquitoe species

    Directory of Open Access Journals (Sweden)

    Montada Dorta Domingo

    1993-01-01

    Full Text Available Three organophosphorus compounds- malathion, folithion and temephos- and two synthetic pyrethroids- alphamethrin and deltamethrin- were used for monitoring the susceptibility status of larvae and adults of six vector mosquitoe species: Culex quinquefasciatus (Filariasis and Aedes albopictus (Dengue (both laboratory and field strains; laboratory strains of Aedes aegypti (Dengue, Anopheles slephensi and Anopheles culicifacies (Malaria, and Culex tritaeniorhynchus (Japanese encephalitis in India. From the LC50 values obtained for these insecticides, it was found that all mosquito species including the field strains of Cx. quinquefasciatus and Ae. albopictus were highly susceptible Except for Cx. quinquefasciatus (field strain against malathion, 100% mortality was observed at the discriminating dosages recommended by World Health Organization. The residual effect of alphamethrin, deltamethrin, malathion and folithion at 25 mg (ai/m² on different surfaces against six species of vector mosquitoes showed that alphamethrin was the most effective on all four treated surfaces (mud, plywood, cement and thatch. Nevertheless, residual efficacy lasted longer on thatch than on the other surfaces. Therefore, synthetic pyrethroids such as alphamethrin can be effectively employed in integrated vector control operations.

  18. Relationship of structure to effectiveness of some organophosphorus insecticides and the crystal and molecular structures of tris(bicarbonato) tetraaquoholmium (III) dihydrate and tris(ethylenediamine-cobalt (III) tetrakis (isothiocyanato cobaltate(II) nitrate

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    Rohrbaugh, W. J.

    1977-06-01

    Results are reported from an investigation of correlations between molecular structural parameters of selected organophosphorus insecticides and their corresponding toxic effectiveness. The crystal and molecular structures of azinphos-methyl, emidithion, and tetrachlorvinphos were determined via three-dimensional x-ray analysis. Acetylcholinesterase (AChE) in nerve cells was identified as the target for organophosphorus insecticides.

  19. An Age-Dependent Physiologically-Based Pharmacokinetic/Pharmacodynamic Model for the Organophosphorus Insecticide Chlorpyrifos in the Preweanling Rat

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    Timchalk, Chuck; Kousba, Ahmed A.; Poet, Torka S.

    2007-08-01

    Juvenile rats are more susceptible than adults to the acute toxicity of organophosphorus insecticides like chlorpyrifos (CPF). Age- and dose-dependent differences in metabolism may be responsible. Of importance is CYP450 activation and detoxification of CPF to chlorpyrifos-oxon (CPF-oxon) and trichloropyridinol (TCP), as well as B-esterase (cholinesterase; ChE) and A-esterase (PON-1) detoxification of CPF-oxon to TCP. In the current study, a modified physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) model incorporating age-dependent changes in CYP450, PON-1, and tissue ChE levels for rats was developed. In this model, age was used as a dependent function to estimate body weight which was then used to allometrically scale both metabolism and tissue ChE levels. Model simulations suggest that preweanling rats are particularly sensitive to CPF toxicity, with levels of CPF-oxon in blood and brain disproportionately increasing, relative to the response in adult rats. This age-dependent non-linear increase in CPF-oxon concentration may potentially result from the depletion of non-target B-esterases, and a lower PON-1 metabolic capacity in younger animals. These results indicate that the PBPK/PD model behaves consistently with the general understanding of CPF toxicity, pharmacokinetics and tissue ChE inhibition in neonatal and adult rats. Hence, this model represents an important starting point for developing a computational model to assess the neurotoxic potential of environmentally relevant organophosphate exposures in infants and children.

  20. Metabolic activation of three arylamines and two organophosphorus insecticides by coriander (Coriandrum sativum) a common edible vegetable.

    Science.gov (United States)

    Cortés-Eslava, J; Gómez-Arroyo, S; Villalobos-Pietrini, R; Espinosa-Aguirre, J J

    2001-12-15

    Organophosphorus insecticides and arylamines, widely distributed in the environment, can be activated into mutagens by plants. Plant activation of three aromatic amines, 4-nitro-o-phenylenediamine (NOP), m-phenylenediamine (m-PDA) and 2-aminofluorene (2AF), and two organophosphorus insecticides, dimethoate and methyl parathion has been the focus of this study. The plant cell/microbe coincubation assay was used employing coriander (Coriandrum sativum) suspended cell cultures as the activating system. Interestingly, this vegetable is included in the Mexican diet and ingested generally uncooked and could have epidemiological consequences. As a genetic end point, the Salmonella typhimurium tester strain TA98 was used. Protein contents, as well as peroxidase activity and peroxidase activity inhibited by diethyldithiocarbamate (DEDTC) of coriander cultures were determined after the coculture. Coriander cells highly activated three aromatic amines, NOP, m-PDA and 2-AF to mutagenic products detected in Salmonella. On the other hand, insecticides were only lightly activated, probably because peroxidase activity of coriander cells was inhibited, corroborated by DEDTC peroxidase inhibition. In all the assays, NOP was the more potent mutagenic compound. The results demonstrated that coriander cells were metabolically competent and suitable for a plant cell microbe coincubation assay, developed to analyze the promutagen activation by plant systems and can be used as a indicator of potential genetic effects.

  1. Organophosphorus pentavalent compounds: history, synthetic methods of preparation and application as insecticides and antitumor agents; Compostos organofosforados pentavalentes: historico, metodos sinteticos de preparacao e aplicacoes como inseticidas e agentes antitumorais

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    Santos, Viviane Martins Rebello dos; Donnici, Claudio Luis [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Quimica; DaCosta, Joao Batista Neves; Caixeiro, Janaina Marques Rodrigues [Universidade Federal Rural do Rio de Janeiro, Seropedica, RJ (Brazil). Dept. de Quimica]. E-mail: dacosta@ufrrj.br

    2007-01-15

    This paper is a review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities. The organophosphorus compounds with agrochemical applications show great structural variety, They include not only insecticides, but also fungicides, herbicides, and others. The large variety of commercially available organophosphorus pesticides is remarkable. Even more interesting is the high efficiency of some organophosphorus compounds as anticancer agents such as cyclophosphamide and its derivatives. (author)

  2. Photocatalytic degradation of selected s-triazine herbicides and organophosphorus insecticides over aqueous TiO2 suspensions.

    Science.gov (United States)

    Konstantinou, I K; Sakellarides, T M; Sakkas, V A; Albanis, T A

    2001-01-15

    The photocatalytic degradation of selected s-triazine herbicides and organophosphorus insecticides was carried out in aqueous TiO2 suspensions under simulated solar light. The tested herbicides from the s-triazines group were atrazine, propazine, cyanazine, prometryne, and irgarol. The tested insecticides from the organophosphorus group were ethyl parathion, methyl parathion, ethyl bromophos, methyl bromophos, and diclofenthion. Degradation kinetics followed first-order reaction and has been monitored through gas chromatography. The degradation was fast with half-lives varying from 10.2 to 38.3 min depending on the nature and the structure of compounds. The generated transformation products (TPs) were formed via oxidation, dealkylation, and dechlorination for s-triazines and via oxidation and photohydrolysis for organophosphates. The TPs of irgarol, bromophos, and dichlofenthion were identified using solid-phase extraction (SDB-disks) and GC-MS techniques, and possible degradation routes were proposed showing similar degradation pathways as for other triazines and organophosporus pesticides. This work points out to the necessity of extended knowledge of the successive steps in a solar-assisted detoxification process.

  3. Molecular and immunological responses of the giant freshwater prawn, Macrobrachium rosenbergii, to the organophosphorus insecticide, trichlorfon.

    Science.gov (United States)

    Chang, Chin-Chyuan; Rahmawaty, Atiek; Chang, Zhong-Wen

    2013-04-15

    Trichlorfon is an organophosphorus (OP) insecticide that is used as an agriculture pesticide to destroy insects, a human medicine to combat internal parasites, and an ectoparasiticide in the livestock and aquaculture industries, but which has caused aquatic toxicity in the prawn industry. The aim of this study was to investigate the effects of trichlorfon on molecular and enzymatic processes of the immunological response of the giant freshwater prawn, Macrobrachium rosenbergii, at 0, 0.2, and 0.4mgL(-1) with 0, 3, 6, 12, and 24h of exposure. The total hemocyte count (THC), respiratory bursts (RBs), phenoloxidase (PO) activity, and superoxide dismutase (SOD) activity were examined to evaluate immunological responses and oxidative stress. Results showed that THCs of the prawn exposed to trichlorfon at both concentrations (0.2 and 0.4mgL(-1)) had increased after 12 and 24h; SOD and PO activities had significantly increased at 3h, whereas production of RBs had dramatically increased as oxidative stress at each sampling time after exposure to trichlorfon compared to the control. A potential biomarker of OPs, acetylcholinesterase (AChE) revealed a significant decrease after exposure for 6h, and showed a time-dependent tendency. Immune gene expressions, including prophenoloxidase (proPO), the lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP), peroxinectin (PE), α2-macroglubulin (α2M), transglutaminase (TG), and copper, zinc (Cu,Zn)-SOD, of prawns exposed to trichlorfon at 0, 0.2, and 0.4mgL(-1) for 0, 6, and 24h were further evaluated. Expressions of all of the immune genes significantly decreased when prawns were exposed to 0.4mgL(-1) trichlorfon for 24h, and among them, an increase in SOD expression was seen after exposure to 0.4mgL(-1) for 6h. Prawns exposed to trichlorfon within 24h exhibited the decrease of circulating hemocytes, and also the induction of oxidative stress, which caused subsequent damage to DNA formation of immune genes. From these

  4. Age-dependent pharmacokinetic and pharmacodynamic response in preweanling rats following oral exposure to the organophosphorus insecticide chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Poet, Torka S.; Kousba, Ahmed A.

    2006-03-01

    Juvenile rats are more susceptible than adults to the acute toxicity of organophosphorus insecticides like chlorpyrifos (CPF). Age- and dose-dependent differences in metabolism may be responsible. Of importance is CYP450 activation and detoxification of CPF to CPF-oxon and 3,5,6-trichloro-2-pyridinol (TCP), as well as B-esterase (cholinesterase; ChE) and A-esterase (PON-1) detoxification of CPF-oxon to TCP. The pharmacokinetics of CPF, TCP, and the extent of blood (plasma/RBC), and brain ChE inhibition in rats were determined on postnatal days (PND) -5, -12, and -17 following oral gavage administration of 1 and 10 mg CPF/kg of body weight. For all neonatal ages the blood TCP exceeded the CPF concentration, and within each age group there was no evidence of non-linear kinetics over the dose range evaluated. Younger animals demonstrated a greater sensitivity to ChE inhibition as evident by the dose- and age-dependent inhibition of plasma, RBC, and brain ChE. Of particular importance was the observation that even in rats as young as PND-5, the CYP450 metabolic capacity was adequate to metabolize CPF to both TCP and CPF-oxon based on the detection of TCP in blood and extensive ChE inhibition (biomarker of CPF-oxon) at all ages. In addition, the increase in the blood TCP concentration ({approx}3-fold) in PND-17 rats relative to the response in the younger animals, and the higher blood concentrations of CPF in neonatal rats (1.7 to 7.5-fold) relative to adults was consistent with an increase in CYP450 metabolic capacity with age. This is the first reported study that evaluated both the pharmacokinetics of the parent pesticide, the major metabolite and the extent of ChE inhibition dynamics in the same animals as a function of neonatal age. The results suggest that in the neonatal rat, CPF was rapidly absorbed and metabolized, and the extent of metabolism was age-dependent.

  5. Rapid method for the determination of some organophosphorus insecticides in a small amount of serum in emergency and occupational toxicology cases

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    Singh Bhoopendra

    2009-01-01

    Full Text Available A simple and rapid method is described for the estimation of some organophosphorus insecticides in the serum of occupationally exposed persons. The compounds are extracted with a mixture of acetone and diethyl ether (1:1 v/v in acidic medium and the extraction residue is analyzed by gas chromatography with nitrogen phosphorus detection method. Linearity was acceptable over concentrations from 0.25 to 4.0 µg/mL. The method percentile recovery for the six different organophosphorus insecticides was 86.3% for phorate, 78.3% for dimethoate, 82.3% for malathion, 79.4% for chlorpyrifos, 80.2% for diazinon, and 68.5% for ethion at the µg/mL level. Serum samples of nine workers who had been occupationally exposed to malathion in an insecticide manufacturing factory, were analyzed and malathion was found at low levels in all the samples.

  6. Structural requirements of organophosphorus insecticides (OPI) to inhibit chicken yolk sac membrane kynurenine formamidase related to OPI teratogenesis.

    Science.gov (United States)

    Seifert, Josef

    2013-03-01

    This paper provides new information related to the mechanism of OPI (organophosphorus insecticides) teratogenesis. The COMFA (comparative molecular field analysis) and COMSIA (comparative molecular similarity indices analysis) suggest that the electrostatic and steric fields are the best predictors of OPI structural requirements to inhibit in ovo chicken embryo yolk sac membrane kynurenine formamidase, the proposed target for OPI teratogens. The dominant electrostatic interactions are localized at nitrogen-1, nitrogen-3, nitrogen of 2-amino substituent of the pyrimidinyl of pyrimidinyl phosphorothioates, and the oxygen of crotonamide carbonyl in crotonamide phosphates. Bulkiness of the substituents at carbon-2 and carbon-6 of the pyrimidinyls and/or N-substituents and carbon-3 substituents of crotonamides are the steric structural components that contribute to superiority of those OPI as in ovo inhibitors of kynurenine formamidase.

  7. Effects of environmentally-relevant mixtures of four common organophosphorus insecticides on the honey bee (Apis mellifera L.).

    Science.gov (United States)

    Al Naggar, Yahya; Wiseman, Steve; Sun, Jianxian; Cutler, G Christopher; Aboul-Soud, Mourad; Naiem, Elsaied; Mona, Mohamed; Seif, Amal; Giesy, John P

    2015-11-01

    We assessed whether exposure to environmentally-relevant mixtures of four organophosphorus insecticides (OPs) exerted adverse effects on honey bees. Adult and worker bees were orally exposed for five days under laboratory conditions to mixtures of four insecticides, diazinon, malathion, profenofos and chlorpyrifos at two concentrations. Concentration in the mixtures tested were equivalent to the median and 95th centile concentrations of the OPs in honey, as reported in the literature. Effects on survival, behavior, activity of acetylcholinesterase (AChE), and expression of genes important in detoxification of xenobiotics and immune response were examined. Survival of worker bees was not affected by exposure to median or 95th centile concentrations of the OPs. Activity of AChE was significantly greater in worker bees exposed to the 95th centile concentration mixture of OPs compared to the median concentration mixture. Expression of genes involved in detoxification of xenobiotics was not affected by treatment, but the abundance of transcripts of the antimicrobial peptide hymenoptaecin was significantly greater in worker honey bees exposed to the median concentration mixture. Results suggest that short-term exposure to environmentally relevant concentrations of a mixture of OPs do not adversely affect worker honey bees.

  8. Validation of an SPME method, using PDMS, PA, PDMS-DVB, and CW-DVB SPME fiber coatings, for analysis of organophosphorus insecticides in natural waters.

    Science.gov (United States)

    Lambropoulou, D A; Sakkas, V A; Albanis, T A

    2002-11-01

    Solid-phase microextraction (SPME) has been optimized and applied to the determination of the organophosphorus insecticides diazinon, dichlofenthion, parathion methyl, malathion, fenitrothion, fenthion, parathion ethyl, bromophos methyl, bromophos ethyl, and ethion in natural waters. Four types of SPME fiber coated with different stationary phases (PDMS, PA, PDMS-DVB, and CW-DVB) were used to examine their extraction efficiencies for the compounds tested. Conditions that might affect the SPME procedure, such as extraction time and salt content, were investigated to determine the analytical performance of these fiber coatings for organophosphorus insecticides. The optimized procedure was applied to natural waters - tap, sea, river, and lake water - spiked in the concentration range 0.5 to 50 micro g L(-1) to obtain the analytical characteristics. Recoveries were relatively high - >80% for all types of aqueous sample matrix - and the calibration plots were reproducible and linear (R(2)>0.982) for all analytes with all the fibers tested. The limits of detection ranged from 2 to 90 ng L(-1), depending on the detector and the compound investigated, with relative standard deviations in the range 3-15% at all the concentration levels tested. The SPME partition coefficients (K(f)) of the organophosphorus insecticides were calculated experimentally for all the polymer coatings. The effect of organic matter such as humic acids on extraction efficiency was also studied. The analytical performance of the SPME procedure using all the fibers in the tested natural waters proved effective for the compounds.

  9. ORIGINAL ARTICLE: Acute Poisoning with Organophosphorus Pesticide: Patients Admitted to A Hospital in Bijapur, Karnataka.

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    Indira A. Hundekari

    2012-01-01

    Full Text Available Background: Organophosphorus compounds are the pesticides most often involved in human poisoning. Toxicity of these compounds is due to the inhibition of acetyl cholinesterase at cholinergic junctions of the nervous system. Aims & Objectives: Toxicities of OP pesticidescause adverse effects on many organs and systems hence the present study was planned to study the plasma Cholinesterase, serumcholesterol and thyroid function tests in acute organophosphorus pesticide poisoning. Materials and Methods: Plasma ChE, serumcholesterol and serum triiodothyronine, thyroxine, and thyroid stimulating hormone levels were estimated using standard methods.Result: In our study we found the maximum (95% cases were suicidal poisoning. We found that the incidence of poisoning was more common among age group between 15-35 years and males (57% were more likely to attempt suicide as compared to females (38%. Among the organophosphorus compounds the most commonly used were dimethoate,monocrotophos, chlorpyriphos. 79% organophosphorus poisoned patients recovered, while 21% died. Plasma Cholinesterase levels were significantly (p<0.001 decreased in all grades of organophosphate poisoning as compared to controls. Inhibition of Plasma Cholinesterase occurs at the time of admission due to toxic effect of organophosphorus compounds; but the levels significantly (p<0.001 normalized after treatment i.e. on the last day of hospitalization. Serum total cholesterol levels significantly decreased (p<0.001 in all grades of organophosphate poisoning cases as compared to controls without any change after treatment as compared with the patients before treatment. There was a slight and nonsignificant decrease in serum triiodothyronine and serum thyroxine levels in organophosphorus poisoning cases without anysignificant change in serum thyroid stimulating hormone levels as compared to control. The organophosphorus poisoned patients after treatment do not show more changes in their

  10. Probabilistic assessment of the cumulative dietary acute exposure of the population of Denmark to organophosphorus and carbamate pesticides

    DEFF Research Database (Denmark)

    Jensen, Bodil Hamborg; Petersen, Annette; Christensen, Tue

    2009-01-01

    Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables...... the nationwide dietary survey conducted in 2000-2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos...

  11. The Effect of Temperature and Humidity on the Susceptibility of Flour Beetles to Organophosphorus Insecticides

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    D. B. Chadha

    1965-01-01

    Full Text Available The effect of the temperature and humidity on the susceptibility of Tribolium castaneum Herbst. to malathion and diazinon, has been investigated. It has been found that temperature significantly influences the susceptibility of T. castaneum to malathion though not to diazinon. Humidity, however, influences the susceptibility if the insect to both insecticides.

  12. Monitoring for resistance to organophosphorus and pyrethroid insecticides in varroa mite populations

    Science.gov (United States)

    The occurrence of resistance in Varroa mite populations is a serious threat to the beekeeping industry and crops that rely on the honey bee for pollination. Integrated pest management strategies for control of this pest include the judicious use of insecticides. To monitor field populations of Varro...

  13. The structural requirements of organophosphorus insecticides (OPI) for reducing chicken embryo NAD(+) content in OPI-induced teratogenesis in chickens.

    Science.gov (United States)

    Seifert, Josef

    2016-05-01

    The objective of this study was to determine the structural requirements of organophosphorus insecticides (OPI) for reducing chicken embryo nicotinamide adenine dinucleotide (NAD(+)) content in OPI-induced teratogenesis and compare them with those needed for OPI inhibition of yolk sac membrane kynurenine formamidase (KFase), the proposed primary target for OPI teratogens in chicken embryos. The comparative molecular field analysis (COMFA) of three-dimensional quantitative structure-activity relationship (3D QSAR) revealed the electrostatic and steric fields as good predictors of OPI structural requirements to reduce NAD(+) content in chicken embryos. The dominant electrostatic interactions were localized at nitrogen-1, nitrogen-3, nitrogen of 2-amino substituent of the pyrimidinyl of pyrimidinyl phosphorothioates, and at the oxygen of crotonamide carbonyl in crotonamide phosphates. Bulkiness of the substituents at carbon-6 of the pyrimidinyls and/or N-substituents of crotonamides was the steric structural component that contributed to superiority of those OPI for reducing embryonic NAD(+) levels. Both electrostatic and steric requirements are similar to those defined in our previous study for OPI inhibition of chicken embryo yolk sac membrane KFase. The findings of this study provide another piece of evidence for the cause-and-effect relationship between yolk sac membrane KFase inhibition and reduced embryo NAD(+) content in NAD-associated OPI-induced teratogenesis in chickens.

  14. A study on oxidative stress and antioxidant status of agricultural workers exposed to organophosphorus insecticides during spraying

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    Rastogi S

    2009-01-01

    Full Text Available Oxidative stress status and Acetylcholinesterase (AChE activity were studied in blood samples obtained from 61 agricultural workers engaged in spraying organophosphorus (OP insecticides in the mango plantation, with a minimum work history of one year, in the age range of 12-55 years. Controls were age-matched, unexposed workers, who never had any exposure to OP pesticides. They were evaluated for oxidative stress markers MDA (end product of lipid peroxidation, reduced glutathione (GSH, and Acetylcholinesterase (AChE and butyrylcholinesterase (BChE levels in blood. The results showed a marked inhibition of the AChE and BChE activities in the sprayers as compared to the controls. The malondialdehyde(MDA, the last product of lipid peroxidation was found to be increased significantly in sprayers(p< 0.05, while depletion in the concentration of antioxidant glutathione(GSH was also observed in the sprayers but the difference was statistically not significant. It was concluded on the basis of biochemical analysis that pesticides sprayers are exposed to more oxidative stress as evidenced by the changes in antioxidant status. The measurement of the AChE and BChE activities in agricultural workers who spray OPs could be a good biomonitoring factor and is recommended to be performed on a regular basis.

  15. Medical treatment of acute poisoning with organophosphorus and carbamate pesticides.

    Science.gov (United States)

    Jokanović, Milan

    2009-10-28

    Organophosphorus compounds (OPs) are used as pesticides and developed as warfare nerve agents such as tabun, soman, sarin, VX and others. Exposure to even small amounts of an OP can be fatal and death is usually caused by respiratory failure. The mechanism of OP poisoning involves inhibition of acetylcholinesterase (AChE) leading to inactivation of the enzyme which has an important role in neurotransmission. AChE inhibition results in the accumulation of acetylcholine at cholinergic receptor sites, producing continuous stimulation of cholinergic fibers throughout the nervous systems. During more than five decades, pyridinium oximes have been developed as therapeutic agents used in the medical treatment of poisoning with OP. They act by reactivation of AChE inhibited by OP. However, they differ in their activity in poisoning with pesticides and warfare nerve agents and there is still no universal broad-spectrum oxime capable of protecting against all known OP. In spite of enormous efforts devoted to development of new pyridinium oximes as potential antidotes against poisoning with OP only four compounds so far have found its application in human medicine. Presently, a combination of an antimuscarinic agent, e.g. atropine, AChE reactivator such as one of the recommended pyridinium oximes (pralidoxime, trimedoxime, obidoxime and HI-6) and diazepam are used for the treatment of OP poisoning in humans. In this article the available data related to medical treatment of poisoning with OP pesticides are reviewed and the current recommendations are presented.

  16. Synthesis, Mechanism of Formation and Insecticidal Activity of Novel Fluorinated Organophosphorus Compounds

    Institute of Scientific and Technical Information of China (English)

    WU,Jun(吴军); HUDSON,Harry R.

    2002-01-01

    The major products of the interaction between triethyl phosphite and 3-fluoropropanoyl chloride at room temperamre are diethyl ( E )-1-( 3-fluoropropanoyioxy )-3-fluoroprop-1-enylphosphonate (3) and diethyl 1-( diethoxyphosphoryl)-3-fluoropropyl phosphate (4). The compounds 3 and 4 were separated by chromatography, and structurally characterized by elemental analysis, NMR spectroscopy (1H, 13C, 19F and 31p) and mass spectrometry. Possible reaction mechanisms are proposed. The major products 3 and 4 were tested for insecticidal activity. 3 gave 100% control of Musca domestica L. and Phaedon cochledriae Fab. at a dose of 20 μg/per insect.

  17. Morbidity in newborns exposed to organophosphorus pesticides

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    Đorđević Momčilo

    2010-01-01

    Full Text Available Introduction. Insecticides are toxines by which we destroy harmful insects. The most frequent insecticides which are used today are organophosphorus pesticides. This group of compounds make substances whose activity mechanism is based on the inhibition of acetylcho­linesterase in nerve synapsis, thus producing holynergic syndrome, resulting from the accumulation of acetylcholine which developed due to the absence of decomposition under the influence of cholinesterase. In the clinical picture of acute toxication by cholinesterase inhibitors there is a clear difference between muscarinic and nicotine effects. The basic aim of the study was to establish the effects of organophosphorus pesticides present in blood and breast milk of mothers on newborns morbidity. Material and methods. The study group consisted of 18 newborns whose mothers had isolated organophosphorus pesticides in their blood and breast­milk on the third day after delivery, and the control group consisted of 84 newborns whose mothers did not have isolated organophosphorus pesticides in their blood and breastmilk. Results. Morbidity is three times greater, often in combination with some disorders of the central nervous system, and the relative risk for its appearance is eight time greater in newborns exposed to organophosphorus pesticides. Disscusion. Disorders that appear in newborns exposed to pesticides are mutagenic, cancerogenic and neurotoxic and some agenses could disturb the immune system which is reflected in morbidity increase, primarly of the central nervous system. Conclusion. The presence of organophosphorus pesticides in blood and breast milk has negative effects on newborns. In addition to acetylcho­linesterase inhibition, organophosphorus pesticides react by means of other mechanisms as well.

  18. Organophosphorus insecticides chlorpyrifos and diazinon and oxidative stress in neuronal cells in a genetic model of glutathione deficiency.

    Science.gov (United States)

    Giordano, Gennaro; Afsharinejad, Zhara; Guizzetti, Marina; Vitalone, Annabella; Kavanagh, Terrance J; Costa, Lucio G

    2007-03-01

    Over the past several years evidence has been accumulating from in vivo animal studies, observations in humans, and in vitro studies, that organophosphorus (OP) insecticides may induce oxidative stress. Such effects may contribute to some of the toxic manifestations of OPs, particularly upon chronic or developmental exposures. The aim of this study was to investigate the role of oxidative stress in the neurotoxicity of two commonly used OPs, chlorpyrifos (CPF) and diazinon (DZ), their oxygen analogs (CPO and DZO), and their "inactive" metabolites (TCP and IMP), in neuronal cells from a genetic model of glutathione deficiency. Cerebellar granule neurons from wild type mice (Gclm +/+) and mice lacking the modifier subunit of glutamate cysteine ligase (Gclm -/-), the first and limiting step in the synthesis of glutathione (GSH), were utilized. The latter display very low levels of GSH and are more susceptible to the toxicity of agents that increase oxidative stress. CPO and DZO were the most cytotoxic compounds, followed by CPF and DZ, while TCP and IMP displayed lower toxicity. Toxicity was significantly higher (10- to 25-fold) in neurons from Gclm (-/-) mice, and was antagonized by various antioxidants. Depletion of GSH from Gclm (+/+) neurons significantly increased their sensitivity to OP toxicity. OPs increased intracellular levels of reactive oxygen species and lipid peroxidation and in both cases the effects were greater in neurons from Gclm (-/-) mice. OPs did not alter intracellular levels of GSH, but significantly increased those of oxidized glutathione (GSSG). Cytotoxicity was not antagonized by cholinergic antagonists, but was decreased by the calcium chelator BAPTA-AM. These studies indicate that cytotoxicity of OPs involves generation of reactive oxygen species and is modulated by intracellular GSH, and suggest that it may involve disturbances in intracellular homeostasis of calcium.

  19. Sublethal effects of an organophosphorus insecticide (RPR-II) on biochemical parameters of tilapia, Oreochromis mossambicus.

    Science.gov (United States)

    Venkateswara Rao, J

    2006-08-01

    The effect of exposure to sublethal concentrations (0.017 mg L(-1), 1/10 of LC50) of the novel organophosphate (OP) insecticide, 2-butenoic acid-3-(diethoxyphosphinothioyl) methyl ester (RPR-II) on biochemical parameters in Oreochromis mossambicus was studied during exposure for 3, 7, 15, 30 and its recovery response after seven days. Acetylcholinesterase (AChE) activity of brain, gill and muscle was inhibited by 67%, 77% and 73% respectively on day-30. The plasma and kidney alanine aminotransferase (AlaAT), and aspartate aminotransferase (AspAT) activity increased, while decreases were observed in gill and liver. Increases in acid phosphatase (AcP), and alkaline phosphatase (AP) activities were observed in plasma, gill, and kidney, and reductions of 20% and 61% in liver AcP and AP, respectively. Depletion of glycogen was observed in all tissues, an indication of typical stress related response of the fish with pesticide. Lactate dehydrogenase (LDH) activity decreased in liver and muscle, indicating tissue damage but a significant increase in LDH activity in gill and brain was observed. Depletion of glutathione (GSH) was observed in all tissues, thereby enhancing lipid peroxidation resulting in cell damage. The induction in hepatic glutathione-S-transferase (GST) levels indicates protection against the toxicity of xenobiotic-induced lipid peroxidation. There was a significant recovery in the above biochemical parameters, in all tissues of fish after a recovery period of seven days. These results revealed that the OP insecticide RPR-II is highly toxic and affects the intermediary metabolism of O. mossambicus.

  20. Compostos organofosforados pentavalentes: histórico, métodos sintéticos de preparação e aplicações como inseticidas e agentes antitumorais Organophosphorus pentavalent compounds: history, synthetic methods of preparation and application as insecticides and antitumor agents

    Directory of Open Access Journals (Sweden)

    Viviane Martins Rebello dos Santos

    2007-02-01

    Full Text Available This paper is a review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities. The organophosphorus compounds with agrochemical applications show great structural variety, They include not only insecticides, but also fungicides, herbicides, and others. The large variety of commercially available organophosphorus pesticides is remarkable. Even more interesting is the high efficiency of some organophosphorus compounds as anticancer agents such as cyclophosphamide and its derivatives.

  1. The role of plant metabolism in the mutagenic and cytotoxic effects of four organophosphorus insecticides in Salmonella typhimurium and in human cell lines.

    Science.gov (United States)

    Cortés-Eslava, Josefina; Gómez-Arroyo, Sandra; Arenas-Huertero, Francisco; Flores-Maya, Saúl; Díaz-Hernández, Martha E; Calderón-Segura, María Elena; Valencia-Quintana, Rafael; Espinosa-Aguirre, Jesús Javier; Villalobos-Pietrini, Rafael

    2013-08-01

    This study used a cell/microbe co-incubation assay to evaluate the effect of four organophosphorus insecticides (parathion-methyl, azinphos-methyl, omethoate, and methamidophos) metabolized by coriander (Coriandrum sativum). The reverse mutation of Salmonella typhimurium strains TA98 and TA100 was used as an indicator of genetic damage. Treatments with these insecticides inhibited peroxidase activity in plant cells by between 17% (omethoate) and 98% (azinphos-methyl) and decreased plant protein content by between 36% (omethoate) and 99.6% (azinphos-methyl). Azinphos-methyl was the most toxic when applied directly. In the Ames test, treatments applied directly to strain TA100 killed the bacteria; however, the presence of plant metabolism detoxified the system and permitted the growth of bacteria. In strain TA98, plant metabolites of insecticides were mutagenic. This result suggests that the tested pesticides produce mutations through frameshifting. The same pesticides were applied to human skin (HaCaT) and lung (NL-20) cell lines to evaluate their effects on cell viability. Pesticides applied directly were more cytotoxic than the combination of pesticide plus coriander metabolic fraction. Omethoate and methamidophos did not affect the viability of HaCaT cells, but azinphos-methyl and parathion-methyl at 100 and 1000μgmL(-1) significantly decreased viability (pinsecticides. All of the treatment conditions caused decreases in NL-20 cell viability (e.g., viability decreased to 12.0% after parathion-methyl treatment, to 14.7% after azinphos-methyl treatment, and to 6.9% after omethoate treatment). Similar to the Ames test, all of the insecticides showed decreased toxicity in human cells when they were cultured in the presence of plant metabolism. In conclusion, when the studied organophosphorus insecticides were plant-metabolized, they induced mutations in the bacterial strain TA98. In human cell lines, plant metabolism reduced the cytotoxic properties of the

  2. Assessing intermittent pesticide exposure from flea control collars containing the organophosphorus insecticide tetrachlorvinphos.

    Science.gov (United States)

    Davis, M Keith; Boone, J Scott; Moran, John E; Tyler, John W; Chambers, Janice E

    2008-11-01

    Fleas are a persistent problem for pets that require implementation of control measures. Consequently, pesticide use by homeowners for flea control is common and may increase pesticide exposure for adults and children. Fifty-five pet dogs (23 in study 1; 22 in study 2) of different breeds and weights were treated with over-the-counter flea collars containing tetrachlorvinphos (TCVP). During study 1, fur of treated dogs was monitored for transferable TCVP residues using cotton gloves to pet the dogs during 5-min rubbings post-collar application. Plasma cholinesterase (ChE) activity was also measured in treated dogs. Average amounts of TCVP transferred from the fur of the neck (rubbing over the collar) and from the back to gloves at 3 days post-collar application were 23,700+/-2100 and 260+/-50 microg/glove, respectively. No inhibition of plasma ChE was observed. During study 2, transferable TCVP residues to cotton gloves were monitored during 5-min rubbings post-collar application. Transferable residues were also monitored on cotton tee shirts worn by children and in the first morning urine samples obtained from adults and children. Average amounts of TCVP transferred to gloves at 5 days post-collar application from the neck (over the collar) and from the back were 22,400+/-2900 and 80+/-20 microg/glove, respectively. Tee shirts worn by children on days 7-11 contained 1.8+/-0.8 microg TCVP/g shirt. No significant differences were observed between adults and children in urinary 2,4,5-trichloromandelic acid (TCMA) levels; however, all TCMA residues (adults and children) were significantly greater than pretreatment concentrations (alpha=0.05). The lack of ChE inhibition in dogs and the low acute toxicity level of TCVP (rat oral LD(50) of 4-5 g/kg) strongly suggest that TCVP is rapidly detoxified and excreted and therefore poses a very low toxicological risk, despite these high residues.

  3. Neurotoxic and teratogenic effects of an organophosphorus insecticide (phenyl phosphonothioic acid-O-ethyl -O-[4-nitrophenyl] ester) on mallard development

    Science.gov (United States)

    Hoffman, D.J.; Sileo, L.

    1984-01-01

    Phenyl phosphonothioic acid-O-ethyl-O-[4-nitrophenyl] ester (EPN) is one of the 10 most frequently used organophosphorus insecticides and causes delayed neurotoxicity in adult chickens and mallards. Small amounts of organophosphorus insecticides placed on birds' eggs are embryotoxic and teratogenic. For this reason, the effects of topical egg application on EPN were examined on mallard (Anas platyrhynchos) embryo development. Mallard eggs were treated topically at 72 hr of incubation with 25 microliter of a nontoxic oil vehicle or with EPN in the vehicle at concentrations of approximately 12, 36, or 108 micrograms/g egg, equivalent to one, three, and nine times the agricultural level of application used to spray crops. Treatment with EPN resulted in 22 to 44% mortality over this dose range by 18 days of development compared with 4 and 5% for untreated and vehicle-treated controls. EPN impaired embryonic growth and was highly teratogenic: 37-42% of the surviving embryos at 18 days were abnormal with cervical and axial scoliosis as well as severe edema. Brain weights were significantly lower in EPN-treated groups at different stages of development including hatchlings. Brain neurotoxic esterase (NTE) activity was inhibited by as much as 91% at 11 days, 81% at 18 days, and 79% in hatchlings. Examination of brain NTE activity during the course of normal development revealed an increase of nearly sixfold from Day 11 through hatching. The most rapid increase occurred between Day 20 and hatching. Brain acetylcholinesterase (AChE) activity was inhibited by as much as 41% at 11 days, 47% at 18 days, and 20% in hatchlings. Plasma cholinesterase and alkaline phosphatase activities were inhibited and plasma aspartate aminotransferase activity was increased at one or more stages of development. Hatchlings from EPN-treated eggs were weaker and slower to right themselves. Histopathological examination did not reveal demyelination and axonopathy of the spinal cord that was

  4. Thin-layer chromatography/direct analysis in real time time-of-flight mass spectrometry and isotope dilution to analyze organophosphorus insecticides in fatty foods.

    Science.gov (United States)

    Kiguchi, Osamu; Oka, Kazuko; Tamada, Masafumi; Kobayashi, Takashi; Onodera, Jun

    2014-11-28

    To assess food safety emergencies caused by highly hazardous chemical-tainted foods, simultaneous analysis of organophosphorus insecticides in fatty foods such as precooked foods was conducted using thin-layer chromatography/direct analysis in real time time-of-flight mass spectrometry (TLC/DART-TOFMS) and isotope dilution technique. Polar (methamidophos and acephate) and nonpolar organophosphorus insecticides (fenitrothion, diazinon, and EPN) were studied. Experiments to ascertain chromatographic patterns using TLC/DART-TOFMS reveal that it was more useful than GC/MS or GC/MS/MS for the simultaneous analyses of polar and nonpolar pesticides, while obviating the addition of a protective agent for tailing effects of polar pesticides. Lower helium gas temperature (260°C) for DART-TOFMS was suitable for the simultaneous analysis of target pesticides. Linearities were achieved respectively at a lower standard concentration range (0.05-5 μg) for diazinon and EPN and at a higher standard concentration range (2.5-25 μg) for methamidophos, acephate, and fenitrothion. Their respective coefficients of determination were ≥ 0.9989 and ≥ 0.9959. A few higher repeatabilities (RSDs) for diazinon and EPN were found (>20%), although isotope dilution technique was used. Application to the HPTLC plate without an automatic TLC sampler might be inferred as a cause of their higher RSDs. Detection limits were estimated in the higher picogram range for diazinon and EPN, and in the lower nanogram range for methamidophos, acephate, and fenitrothion. Aside from methamidophos, recovery results (n=3) obtained using a highly insecticide-tainted fatty food (dumpling) and raw food (grapefruit) samples (10mg/kg) using TLC/DART-TOFMS with both complex and simpler cleanups were not as susceptible to matrix effects (95-121%; RSD, 1.3-14%) as those using GC/MS/MS (102-117%; RSD, 0.4-8.5%), although dumpling samples using GC/MS were remarkably susceptible to matrix effects. The coupled method of

  5. A phase II clinical trial to assess the safety of clonidine in acute organophosphorus pesticide poisoning

    Directory of Open Access Journals (Sweden)

    Karunatilake Harindra

    2009-08-01

    Full Text Available Abstract Background An estimated 2–3 million people are acutely poisoned by organophosphorus pesticides each year, mostly in the developing world. There is a pressing need for new affordable antidotes and clonidine has been shown to be effective in animal studies. Our aim was to determine the safety of clonidine given as an antidote in adult patients presenting with signs or symptoms of acute organophosphate ingestion. Methods This study was a dose finding, open-label, multicentre, phase II trial. Forty eight patients with acute organophosphate poisoning were randomized to receive either clonidine or placebo: Four to receive placebo and twelve to receive clonidine at each dose level. The first dose level was an initial loading dose of 0.15 mg followed by an infusion of 0.5 mg of clonidine over 24 hours. The initial loading dose was increased to 0.3 mg, 0.45 and 0.6 mg. at all dosing levels however the subsequent infusion remained at 0.5 mg of clonidine over 24 hours. Results The baseline characteristics of both groups were similar. The trial was stopped after completion of the 3rd dosing level. At the 1st and 2nd dosing level there were no reported adverse drug reactions. At the 3rd dosing level 5 patients (42% developed significant hypotension during clonidine treatment that responded to intravenous fluids. There were no statistical differences in ventilation rate, pre and post GCS, and mortality rates over all levels. Conclusion Our findings suggest use of moderate doses of clonidine in acute organophosphate poisoning can be used without causing frequent clinical problems but that higher doses are associated with a high incidence of hypotension requiring intervention. Further studies are needed to study the efficacy of clonidine as an antidote in organophosphate poisoning. Trial registration Current Controlled Trial ISRCTN89917816.

  6. Slow Repetitive Nerve Stimulation in Patients with Acute Organophosphorus Poisoning after Clinical Recovery

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    Sudheera Jayasinghe

    2013-03-01

    Full Text Available Background: Prolonged inhibition of acetylcholine esterase may lead to the intermediate syndrome. Neuromuscular junction (NMJ dysfunction has been shown with repetitive nerve stimulation (RNS. Subclinical NMJ dysfunction may also occur. We aimed to examine the NMJ function following acute organophosphorus (OP poisoning by using exercise modified slow RNS. Methods: A cohort study was conducted with matched controls. Patients with acute OP poisoning were enrolled. NMJ function, muscle power and tendon reflexes were assessed at discharge and six weeks after exposure. NMJ function was assessed with exercise modified supramaximal slow RNS of the median nerve. Results: There were 68 patients and 71 controls. Mean (SD age of patients and controls were 32 (12 and 33 (12 years. In some particular amplitude, the decrement response was statistically significant. They were decrement response at rest, at fourth amplitude (95% CI: -0.2 to -2.7 and two minutes post-exercise at fourth and fifth amplitudes (95% CI: -0.8 to -5, -1 to -5 respectively in the second assessment compared to controls, decrement response at rest at fourth and fifth amplitudes (95% CI: -4 to -0.5, -3.9 to -0.01 respectively and two minutes post-exercise at fourth amplitude (95% CI: -5 to -0.8 in the second assessment compared to the first assessment. Patients in the first assessment and controls showed more than 8% decrement response either to the second, fourth or fifth stimuli in seven and five occasions respectively. Conclusion:  There was no significant neuromuscular junction dysfunction assessed by exercise modified slow repetitive stimulation following acute exposure to OP. Since, NMJ dysfunctions are likely to occur following OP poisoning, other electrodiagnostic modalities such as SF-EMG are probably more efficient to assess these abnormalities.

  7. Oral delivery mediated RNA interference of a carboxylesterase gene results in reduced resistance to organophosphorus insecticides in the cotton Aphid, Aphis gossypii Glover.

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    You-Hui Gong

    Full Text Available BACKGROUND: RNA interference (RNAi is an effective tool to examine the function of individual genes. Carboxylesterases (CarE, EC 3.1.1.1 are known to play significant roles in the metabolism of xenobiotic compounds in many insect species. Previous studies in our laboratory found that CarE expression was up-regulated in Aphis gossypii (Glover (Hemiptera: Aphididae adults of both omethoate and malathion resistant strains, indicating the potential involvement of CarE in organophosphorus (OP insecticide resistance. Functional analysis (RNAi is therefore warranted to investigate the role of CarE in A. gossypii to OPs resistance. RESULT: CarE expression in omethoate resistant individuals of Aphis gossypii was dramatically suppressed following ingestion of dsRNA-CarE. The highest knockdown efficiency (33% was observed at 72 h after feeding when dsRNA-CarE concentration was 100 ng/µL. The CarE activities from the CarE knockdown aphids were consistent with the correspondingly significant reduction in CarE expression. The CarE activity in the individuals of control aphids was concentrated in the range of 650-900 mOD/per/min, while in the individuals of dsRNA-CarE-fed aphids, the CarE activity was concentrated in the range of 500-800 mOD/per/min. In vitro inhibition experiments also demonstrated that total CarE activity in the CarE knockdown aphids decreased significantly as compared to control aphids. Bioassay results of aphids fed dsRNA-CarE indicated that suppression of CarE expression increased susceptibility to omethoate in individuals of the resistant aphid strains. CONCLUSION: The results of this study not only suggest that ingestion of dsRNA through artificial diet could be exploited for functional genomic studies in cotton aphids, but also indicate that CarE can be considered as a major target of organophosphorus insecticide (OPs resistance in A. gossypii. Further, our results suggest that the CarE would be a propitious target for OPs resistant

  8. Comparative Pharmacokinetics of the Organophosphorus Insecticide Chlorpyrifos and its Major Metabolites Diethylphosphate, Diethylthiophosphate and 3,5,6-Trichloro-2-pyridinol in the Rat

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Busby, Andrea L; Campbell, James A; Needham, Larry L; Barr, Dana

    2007-07-31

    Abstract Chlorpyrifos (CPF) is a commonly used diethylphosphorothionate organophosphorus (OP) insecticide. Diethylphosphate (DEP), diethylthiophosphate (DETP) and 3,5,6-trichloro-2-pyridinol (TCPy) are products of metabolism and of environmental degradation of CPF and are routinely measured in urine as biomarkers of exposure. However, because these same chemicals can result from metabolism or by biodegradation, monitoring total urinary metabolite levels may be reflective of not only an individual’s contact with the parent pesticide, but also exposure with the metabolites, which are present in the environment. The objective of the current study was to compare the pharmacokinetics of orally administered DEP, DETP and TCPy with their kinetics following oral dosing with the parent insecticide CPF in the rat. Groups of rats were orally administered CPF, DEP, TCPy or DETP at doses of 140 μmol/kg body weight, and the time-courses of the metabolites were evaluated in blood and urine. Following oral administration, all three metabolites were well absorbed with peak blood concentrations being attained between 1-3 h post-dosing. In the case of DEP and TCPy virtually all the administered dose was recovered in the urine by 72 h post-dosing, suggesting negligible, if any, metabolism; whereas with DETP, ~50% of the orally administered dose was recovered in the urine. The CPF oral dose was likewise rapidly absorbed and metabolized to DEP, TCPy and DETP, with the distribution of metabolites in the urine followed the order: TCPy (22 ± 3 μmol) > DETP (14 ± 2 μmol) > DEP (1.4 ± 0.7 μmol). Based upon the total amount of TCPy detected in the urine a minimum of 63% of the oral CPF dose was absorbed. These studies support the hypotheses that DEP, DETP and TCPy present in the environment can be readily absorbed and eliminated in the urine of rats and potentially humans.

  9. Measurement of pyrethroid, organophosphorus, and carbamate insecticides in human plasma using isotope dilution gas chromatography-high resolution mass spectrometry.

    Science.gov (United States)

    Pérez, José J; Williams, Megan K; Weerasekera, Gayanga; Smith, Kimberly; Whyatt, Robin M; Needham, Larry L; Barr, Dana Boyd

    2010-10-01

    We have developed a gas chromatography-high resolution mass spectrometry method for measuring pyrethroid, organophosphorus, carbamate and fipronil pesticides and the synergist piperonyl butoxide in human plasma. Plasma samples were extracted using solid phase extraction and were then concentrated for injection and analysis using isotope dilution gas chromatography-high resolution mass spectrometry. The limits of detection ranged from 10 to 158 pg/mL with relative recoveries at concentrations near the LODs (e.g., 25 or 250 pg/mL) ranging from 87% to 156% (9 of the 16 compounds were within ±15% of 100%). The extraction recoveries ranged from 20% to 98% and the overall method relative standard deviations were typically less than 20% with some exceptions. Analytical characteristics were determined at 25, 250, and 1000 pg/mL.

  10. Biodegradation of the organophosphorus insecticide diazinon by Serratia sp. and Pseudomonas sp. and their use in bioremediation of contaminated soil.

    Science.gov (United States)

    Cycoń, Mariusz; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2009-07-01

    An enrichment culture technique was used for the isolation of bacteria responsible for biodegradation of diazinon in soil. Three bacterial strains were screened and identified by MIDI-FAME profiling as Serratia liquefaciens, Serratia marcescens and Pseudomonas sp. All isolates were able to grow in mineral salt medium (MSM) supplemented with diazinon (50 mgL(-1)) as a sole carbon source, and within 14d 80-92% of the initial dose of insecticide was degraded by the isolates and their consortium. Degradation of diazinon was accelerated when MSM was supplemented with glucose. However, this process was linked with the decrease of pH values, after glucose utilization. Studies on biodegradation in sterilized soil showed that isolates and their consortium exhibited efficient degradation of insecticide (100mg kg(-1) soil) with a rate constant of 0.032-0.085d(-1), and DT(50) for diazinon was ranged from 11.5d to 24.5d. In contrast, degradation of insecticide in non-sterilized soil, non-supplemented earlier with diazinon, was characterized by a rate constant of 0.014d(-1) and the 7-d lag phase, during which only 2% of applied dose was degraded. The results suggested a strong correlation between microbial activity and chemical processes during diazinon degradation. Moreover, isolated bacterial strains may have potential for use in bioremediation of diazinon-contaminated soils.

  11. Relationship between Acute Organophosphorus Pesticide Poisoning and Damages Induced by Free Radicals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To study the relationship between abnormal reactions of free radicals in bodies of patients with acute organophosphorus pesticide poisoning (AOPP) and damages induced by free radicals. Methods 58 AOPP patients and 58 healthy adult volunteers (HAV) were enrolled in an independent samples control design, in which spectrophotometric methods were used to determine the concentrations of nitric oxide (NO) and lipoperoxides (LPO) in plasma, and LPO in erythrocytes, vitamin C (VC), vitamin E (VE) and b-carotene (b-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and acetylcholinesterase (AChE) in erythrocytes. Results Compared with the average values of every biochemical parameter in the HAV group, the average values of LPO in plasma and in erythrocytes, and NO in plasma in the AOPP group were significantly increased (P=0.000001), while the average values of VC, VE, a-CAR in plasma as well as SOD, CAT, GSH-Px and AChE in erythrocytes in the AOPP group were significantly decreased (P=0.000001). The findings of Pearson product-moment correlation analysis between the value of AChE in erythrocytes and the values of above biochemical parameters for 58 AOPP patients showed that there was a significant linear negative correlation between AChE in erythrocytes and LPO, NO in plasma, and LPO in erythrocytes (P=0.000001~0.001319), while there was a significant linear positive correlation between AChE in erythrocytes and VC, VE, a-CAR in plasma as well as SOD, CAT, GSH-Px in erythrocytes (P=0.000013~0.000824). The results of discriminant analysis of above chemical parameters for 58 AOPP patients and 58 HAV suggested that the correct rates of discriminant analysis were increased to 100 % when the values of AChE and LPO in plasma and in erythrocytes, or AChE and others, were jointly used for the discriminant analysis. Conclusion The findings of the present study suggest that a series of free radical

  12. Development of a Non-Invasive Biomonitoring Approach to Determine Exposure to the Organophosphorus Insecticide Chlorpyrifos in Rat Saliva

    Energy Technology Data Exchange (ETDEWEB)

    Timchalk, Chuck; Campbell, James A.; Liu, Guodong; Lin, Yuehe; Kousba, Ahmed A.

    2007-03-01

    Abstract Non-invasive biomonitoring approaches are being developed using reliable portable analytical systems to quantify dosimetry utilizing readily obtainable body fluids, such as saliva. In the current study, rats were given single oral gavage doses (1, 10 or 50 mg/kg) of the insecticide chlorpyrifos (CPF), saliva and blood were collected from groups of animals (4/time-point) at 3, 6, and 12 hr post-dosing, and the samples were analyzed for the CPF metabolite trichlorpyridinol (TCP). Trichlorpyridinol was detected in both blood and saliva at all doses and the TCP concentration in blood exceeded saliva, although the kinetics in blood and saliva were comparable. A physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model for CPF incorporated a compartment model to describe the time-course of TCP in blood and saliva. The model adequately simulated the experimental results over the dose ranges evaluated. A rapid and sensitive sequential injection (SI) electrochemical immunoassay was developed to monitor TCP, and the reported detection limit for TCP in water was 6 ng/L. Computer model simulation in the range of the Allowable Daily Intake (ADI) or Reference Dose (RfD) for CPF (0.01-0.003 mg/kg/day) suggest that the electrochemical immunoassay had adequate sensitivity to detect and quantify TCP in saliva at these low exposure levels. To validate this approach further studies are needed to more fully understand the pharmacokinetics of CPF and TCP excretion in saliva. The utilization of saliva as a biomonitoring matrix, coupled to real-time quantitation and PBPK/PD modeling represents a novel approach with broad application for evaluating both occupational and environmental exposures to insecticides.

  13. Altered quantities and in vivo activities of cholinesterase from Daphnia magna in sub-lethal exposure to organophosphorus insecticides.

    Science.gov (United States)

    Liu, Hongcui; Yuan, Bingqiang; Li, Shaonan

    2012-06-01

    For investigating relationship between activity of cholinesterase (ChE) and ambient concentration of anticholinesterases, Daphnia magna had been exposed for 21 day to sub-lethal concentrations, i.e. 1/6 EC(50), 1/36 EC(50), and 1/216 EC(50), of either triazophos or chlorpyrifos. Samples were taken at different points of time for measuring total activity and immunoreactive content of ChE and actual concentrations of the anticholinesterases. A type of antigen formerly developed by immunizing mice with purified ChE was utilized in this study to establish an indirect non-competitive ELISA for measuring immunoreactive content of ChE in Daphnia. Studies showed that for apparent activity, i.e. activity that was scaled with total protein, the insecticides caused 5.2-6.9 percent inhibition and 17.0-17.7 percent inductions during the 21 d exposure, whereas for inherent activity, i.e. activity that was scaled with immunoreactive protein, no induction was detected during the exposure. Accompanied by up to 65.9 percent and 68.0 percent promotion in terms of the immunoreactive content, up to 42.8 percent and 44.6 percent inhibition in terms of the inherent activity was indicated, respectively, for triazophos and chlopyrifos. Judged by measured concentrations, the inherent activity recovered faster than the rate of dissipation of the anticholinesterases. Result of the study suggested that the inherent activity was more sensitive than the apparent one in predicting sub-lethal and/or long-term stress of anticholinesterases. It also suggested that apart from promotion in terms of content of the ChE, the Daphnia developed capacities to block bio-concentration of anticholinesterases, and these capacities would make it liable to underestimate ambient concentration of anticholinesterases along with the time of exposure.

  14. An amperometric biosensor based on acetylcholinesterase immobilized onto iron oxide nanoparticles/multi-walled carbon nanotubes modified gold electrode for measurement of organophosphorus insecticides

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, Nidhi [Department of Biochemistry, M.D. University, Rohtak 124001, Haryana (India); Pundir, Chandra Shekhar, E-mail: pundircs@rediffmail.com [Department of Biochemistry, M.D. University, Rohtak 124001, Haryana (India)

    2011-09-02

    Graphical abstract: The stepwise amperometric biosensor fabrication process and immobilized acetylcholinesterase inhibition in pesticide solution. Highlights: {center_dot} Constructed a novel composite material using Fe{sub 3}O{sub 4}NP and c-MWCNT at Au electrode for electrocatalysis. {center_dot} The properties of nanoparticles modified electrodes were studied by SEM, FTIR, CVs and EIS. {center_dot} The biosensor exhibited good sensitivity (0.475 mA {mu}M{sup -1}) {center_dot} The half life of electrode was 2 months. {center_dot} The sensor was suitable for trace detection of OP pesticide residues in milk and water. - Abstract: An acetylcholinesterase (AChE) purified from maize seedlings was immobilized covalently onto iron oxide nanoparticles (Fe{sub 3}O{sub 4}NP) and carboxylated multi walled carbon nanotubes (c-MWCNT) modified Au electrode. An organophosphorus (OP) biosensor was fabricated using this AChE/Fe{sub 3}O{sub 4}/c-MWCNT/Au electrode as a working electrode, Ag/AgCl as standard and Pt wire as an auxiliary electrode connected through a potentiostat. The biosensor was based on inhibition of AChE by OP compounds/insecticides. The properties of nanoparticles modified electrodes were studied by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), cyclic voltammograms (CVs) and electrochemical impedance spectroscopy (EIS). The synergistic action of Fe{sub 3}O{sub 4}NP and c-MWCNT showed excellent electrocatalytic activity at low potential (+0.4 V). The optimum working conditions for the sensor were pH 7.5, 35 deg. C, 600 {mu}M substrate concentration and 10 min for inhibition by pesticide. Under optimum conditions, the inhibition rates of OP pesticides were proportional to their concentrations in the range of 0.1-40 nM, 0.1-50 nM, 1-50 nM and 10-100 nM for malathion, chlorpyrifos, monocrotophos and endosulfan respectively. The detection limits were 0.1 nM for malathion and chlorpyrifos, 1 nM for monocrotophos and 10 nM for endosulfan. The

  15. Gastric Lavage in Acute Organophosphorus Pesticide poisoning (GLAOP – a randomised controlled trial of multiple vs. single gastric lavage in unselected acute organophosphorus pesticide poisoning

    Directory of Open Access Journals (Sweden)

    Cao YuPing

    2006-10-01

    Full Text Available Abstract Background Organophosphorus (OP pesticide poisoning is the most common form of pesticide poisoning in many Asian countries. Guidelines in western countries for management of poisoning indicate that gastric lavage should be performed only if two criteria are met: within one hour of poison ingestion and substantial ingested amount. But the evidence on which these guidelines are based is from medicine overdoses in developed countries and may be irrelevant to OP poisoning in Asia. Chinese clinical experience suggests that OP remains in the stomach for several hours or even days after ingestion. Thus, there may be reasons for doing single or multiple gastric lavages for OP poisoning. There have been no randomised controlled trials (RCTs to assess this practice of multiple lavages. Since it is currently standard therapy in China, we cannot perform a RCT of no lavage vs. a single lavage vs. multiple lavages. We will compare a single gastric lavage with three gastric lavages as the first stage to assess the role of gastric lavage in OP poisoning. Methods/Design We have designed an RCT assessing the effectiveness of multiple gastric lavages in adult OP self-poisoning patients admitted to three Chinese hospitals within 12 hrs of ingestion. Patients will be randomised to standard treatment plus either a single gastric lavage on admission or three gastric lavages at four hour intervals. The primary outcome is in-hospital mortality. Analysis will be on an intention-to-treat basis. On the basis of the historical incidence of OP at the study sites, we expect to enroll 908 patients over three years. This projected sample size provides sufficient power to evaluate the death rate; and a variety of other exposure and outcome variables, including particular OPs and ingestion time. Changes of OP level will be analyzed in order to provide some toxic kinetic data. Discussion the GLAOP study is a novel, prospective cohort study that will explore to the toxic

  16. 超声波萃取气相色谱法检测白菜干中的有机磷农药残留%Determination of organophosphorus insecticides residues in dry cabbages by ultrasonic extraction-gas chromatography

    Institute of Scientific and Technical Information of China (English)

    刘红梅; 黎小鹏; 李文英

    2012-01-01

    In order to detect familiar organophosphorus insecticides residues more accurately and more conveniently, a detection method was established for the determination of 12 organophosphorus insecti- cides residues i methamidophos, isofenphos-methy n dry cabbages by ultrasonic extraction-gas chromatography, including dichlorvos, acephate, phorate, omethoate, dimethoate, chlorpyrifos, parathion-methyl, fenitrothion, 1, parathion and isocarbophos. The results showed that the 12 organophosphorus insecti- cides concentration range of linearity was 0. 01 - 1.00 μg/mL. The percent recoveries were 70. 6% - 112. 1% , coefficients of variation (CV) were 1.6% - 15.2% , and the detection limits were 0. 004 - 0. 026 mg/kg. Some samples collected from market were determined by this method system. It was found that the residue was 0. 243 mg/kg for chlorpyrifos with 1.7% of CV, and the other 11 organophosphorus insecticides were not found. This method was precise, high sensitivity and more convenient, and met the need of organophosphorus insecticides residues detection.%为了更准确、简便地检测白菜干中常见的有机磷农药残留,建立了超声波萃取气相色谱法检测白菜干中敌敌畏、甲胺磷、乙酰甲胺磷、甲拌磷、氧乐果、乐果、毒死蜱、甲基对硫磷、杀螟硫磷、甲基异柳磷、对硫磷和水胺硫磷等12种有机磷农药残留的方法.结果表明,12种有机磷农药在0.01-1.00μg/mL范围内具有良好的线性关系,回收率为70.6%-112.1%,变异系数1.6%-15.2%,方法检出限为0.004-0.026mg/kg.实际检测样品时,于白菜干样品中仅检出毒死蜱残留量为0.243mg/kg,变异系数为1.7%,其余11种有机磷农药未检出.该方法定量准确、灵敏度高、操作简便,适用于白菜干中常见的12种有机磷农药残留的检测.

  17. Organophosphorus pesticide poisoning : cases and developments

    NARCIS (Netherlands)

    Aardema, H.; Ligtenberg, J. J. M.; Peters-Polman, O. M.; Tulleken, J. E.; Zijlstra, J. G.; Meertens, John H. J. M.

    2008-01-01

    Self-poisoning with organophosphate pesticides is a major health problem world-wide. Through the inhibition of acetylcholinesterase, organophosphorus poisoning is characterised by the clinical picture of acute cholinergic crisis. Other manifestations are the intermediate neurotoxic syndrome and dela

  18. Habitat availability is a more plausible explanation than insecticide acute toxicity for U.S. grassland bird species declines.

    Science.gov (United States)

    Hill, Jason M; Egan, J Franklin; Stauffer, Glenn E; Diefenbach, Duane R

    2014-01-01

    Grassland bird species have experienced substantial declines in North America. These declines have been largely attributed to habitat loss and degradation, especially from agricultural practices and intensification (the habitat-availability hypothesis). A recent analysis of North American Breeding Bird Survey (BBS) "grassland breeding" bird trends reported the surprising conclusion that insecticide acute toxicity was a better correlate of grassland bird declines in North America from 1980-2003 (the insecticide-acute-toxicity hypothesis) than was habitat loss through agricultural intensification. In this paper we reached the opposite conclusion. We used an alternative statistical approach with additional habitat covariates to analyze the same grassland bird trends over the same time frame. Grassland bird trends were positively associated with increases in area of Conservation Reserve Program (CRP) lands and cropland used as pasture, whereas the effect of insecticide acute toxicity on bird trends was uncertain. Our models suggested that acute insecticide risk potentially has a detrimental effect on grassland bird trends, but models representing the habitat-availability hypothesis were 1.3-21.0 times better supported than models representing the insecticide-acute-toxicity hypothesis. Based on point estimates of effect sizes, CRP area and agricultural intensification had approximately 3.6 and 1.6 times more effect on grassland bird trends than lethal insecticide risk, respectively. Our findings suggest that preserving remaining grasslands is crucial to conserving grassland bird populations. The amount of grassland that has been lost in North America since 1980 is well documented, continuing, and staggering whereas insecticide use greatly declined prior to the 1990s. Grassland birds will likely benefit from the de-intensification of agricultural practices and the interspersion of pastures, Conservation Reserve Program lands, rangelands and other grassland habitats into

  19. Acute toxicities and sublethal effects of some conventional insecticides on Trichogramma chilonis (Hymenoptera: Trichogrammatidae).

    Science.gov (United States)

    Wang, De-Sen; He, Yu-Rong; Guo, Xiang-Ling; Luo, Yong-Li

    2012-08-01

    The acute toxicity of 10 conventional insecticides to adult of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) was bioassayed by membrane method, and then their sublethal effects on the parasitoid were evaluated in the laboratory. Based on sublethal concentration (LC30) values at 8 h after treatment, we determined that adult T. chilonis were the most susceptible to chlorfenapyr, followed by fipronil, spinosad, avermectins, beta-cypermethrin, and cartap, with lethal concentration (LC)30 values of 0.3133, 0.3269, 1.5408, 3.2961, 6.1469, and 9.021 mg/liter, respectively. The field-recommended concentrations of chlorfluazuron, indoxacarb, Bacillus thuringiensis, and tebufenozide caused Cartap and spinosad also reduced longevity (8 and 7.9 d) and fecundity (110.77 and 117.2) of treated adults, but cartap enhanced the female percentage of F1 offspring (61.6%), resulting a statistical higher R0, r(m), and lambda of treated T. chilonis. In contrast, chlorfluazuron and tebufenozide increased longevity (16.4 and 15.4 d) and fecundity (248 and 256.9) of treated adults but slightly decreased the female percentage of F1 offspring (31.4 and 38.1%). Although chlorfenapyr showed no adverse influence on longevity and fecundity, it remarkably reduced the female percentage of F1 offspring (13.5%), leading to a lower R0, r(m), and lambda of treated T. chilonis. Indoxacarb, B. thuringiensis, and beta-cypermethrin had no obvious sublethal effects on the longevity and fecundity of treated adults. Based on these results, we consider B. thuringienesis, chlorfluazuron, indoxacarb, beta-cypermethrin, and tebufenozide safe to T. chilonis, suggesting that these insecticides are compatible with this parasitoid when being used in the field. However, fipronil, chlorfenapyr, spinosad, and avermectins were very harmful to T. chilonis. Timing of application of these insecticides was critical.

  20. Acute effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate, on cardiovascular parameters in anaesthetized, artificially ventilated rats

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yoshimasa [Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Itoh, Takeo, E-mail: titoh@med.nagoya-cu.ac.jp [Department of Pharmacology, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Shiraishi, Hiroaki [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Maeno, Yoshitaka [Department of Forensic Medical Science, Graduate School of Medical Sciences, Nagoya City University, Nagoya (Japan); Arima, Yosuke; Torikoshi, Aiko; Namera, Akira [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Makita, Ryosuke [Department of Nursing, Faculty of Health Sciences, Hiroshima Cosmopolitan University, Hiroshima (Japan); Yoshizumi, Masao [Department of Cardiovascular Physiology and Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Nagao, Masataka [Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan)

    2013-10-01

    The organophosphorus compound sarin irreversibly inhibits acetylcholinesterase. We examined the acute cardiovascular effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate (BIMP), in anaesthetized, artificially ventilated rats. Intravenous administration of BIMP (0.8 mg/kg; the LD50 value) induced a long-lasting increase in blood pressure and tended to increase heart rate. In rats pretreated with the non-selective muscarinic-receptor antagonist atropine, BIMP significantly increased both heart rate and blood pressure. In atropine-treated rats, hexamethonium (antagonist of ganglionic nicotinic receptors) greatly attenuated the BIMP-induced increase in blood pressure without changing the BIMP-induced increase in heart rate. In rats treated with atropine plus hexamethonium, intravenous phentolamine (non-selective α-adrenergic receptor antagonist) plus propranolol (non-selective β-adrenergic receptor antagonist) completely blocked the BIMP-induced increases in blood pressure and heart rate. In atropine-treated rats, the reversible acetylcholinesterase inhibitor neostigmine (1 mg/kg) induced a transient increase in blood pressure, but had no effect on heart rate. These results suggest that in anaesthetized rats, BIMP induces powerful stimulation of sympathetic as well as parasympathetic nerves and thereby modulates heart rate and blood pressure. They may also indicate that an action independent of acetylcholinesterase inhibition contributes to the acute cardiovascular responses induced by BIMP. - Highlights: • A sarin-like agent BIMP markedly increased blood pressure in anaesthetized rats. • Muscarinic receptor blockade enhanced the BIMP-induced increase in blood pressure. • Ganglionic nicotinic receptor blockade attenuated the BIMP-induced response. • Blockade of α- as well as β-receptors attenuated the BIMP-induced response.

  1. Further assessment of an in vitro screen that may help identify organophosphorus pesticides that are more acutely toxic to the young.

    Science.gov (United States)

    Padilla, S; Sung, H-J; Moser, V C

    2004-09-24

    Some, but not all, organophosphorus pesticides are more acutely toxic to the young as compared to adults. We have developed an in vitro assay that measures the detoxification potential (via carboxylesterase and A-esterases) of tissues. Previous results using this in vitro screen correlated with the marked in vivo sensitivity of the young to chlorpyrifos and also correlated with the equal sensitivity of the young and adult to methamidophos (Padilla et al., 2000). We have now extended these observations to two other pesticides that have already been shown in the literature to be more toxic to the young: parathion (paraoxon) and malathion (malaoxon). In our in vitro assay, liver or plasma from 7-d-old rats were much less efficacious than adult tissues at detoxification of the active metabolites of these two pesticides. Using our in vitro assay we also tested the active metabolite of diazinon, diazoxon, and again found that young liver or plasma possessed much less detoxification capability than adult tissues. From these results, we predicted that young animals would be more sensitive to diazinon, which, in fact, was the case: When postnatal day (PND) 17 or adult rats were given a dosage of 75 mg/kg diazinon, adult brain cholinesterase (ChE) was only inhibited 38%, while the brain ChE in the PND 17 animals showed much more inhibition (75%). We conclude that our in vitro screen may prove to be a useful, quick, convenient test for identifying which organophosphorus pesticides may be more acutely toxic to the young as compared to adults.

  2. In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid to gill cell line of flounder Paralichthy olivaceus

    Science.gov (United States)

    Su, Feng; Zhang, Shicui; Li, Hongyan; Guo, Huarong

    2007-04-01

    In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR. MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI.

  3. In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid to gill cell line of flounder Paralichthy olivaceus

    Institute of Scientific and Technical Information of China (English)

    SU Feng; ZHANG Shicui; LI Hongyan; GUO Huarong

    2007-01-01

    In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR, MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI.

  4. [The initial activity and persistance of an experimental larvicide with a base of Bacillus thuringiensis var. israelensis and a commercial preparation containing the organophosphorus insecticide temephos].

    Science.gov (United States)

    Pussemier, L; De Borger, R

    1984-08-01

    The larvicide activity of the experimental preparation SAN 402 I WDC containing B. Thuringiensis var. Israelensis and that of Abate 500 E (44 % temephos) were tested on the larvae of Aedes aegypti. The studies were performed on the following media: distilled water, pure and buffered at pH 9, 7 and 4 and pond water whether or not free from materials in suspension. The activity of both preparations is not influenced by the composition of the media, exception made for the presence of materials in suspension. The persistance varies according to the kind of the media and the concentration level. It is in general rather low. Both preparations behave rather similar, the microbial insecticide however is more influenced by the presence of materials in suspension.

  5. Evaluation of organophosphorus and synthetic pyrethroid insecticides against six vector mosquitoe species Avaliação de inseticidas organofosforados e piretroides sintéticos contra seis mosquitos vetores

    Directory of Open Access Journals (Sweden)

    Domingo Montada Dorta

    1993-12-01

    Full Text Available Three organophosphorus compounds- malathion, folithion and temephos- and two synthetic pyrethroids- alphamethrin and deltamethrin- were used for monitoring the susceptibility status of larvae and adults of six vector mosquitoe species: Culex quinquefasciatus (Filariasis and Aedes albopictus (Dengue (both laboratory and field strains; laboratory strains of Aedes aegypti (Dengue, Anopheles slephensi and Anopheles culicifacies (Malaria, and Culex tritaeniorhynchus (Japanese encephalitis in India. From the LC50 values obtained for these insecticides, it was found that all mosquito species including the field strains of Cx. quinquefasciatus and Ae. albopictus were highly susceptible Except for Cx. quinquefasciatus (field strain against malathion, 100% mortality was observed at the discriminating dosages recommended by World Health Organization. The residual effect of alphamethrin, deltamethrin, malathion and folithion at 25 mg (ai/m² on different surfaces against six species of vector mosquitoes showed that alphamethrin was the most effective on all four treated surfaces (mud, plywood, cement and thatch. Nevertheless, residual efficacy lasted longer on thatch than on the other surfaces. Therefore, synthetic pyrethroids such as alphamethrin can be effectively employed in integrated vector control operations.Três compostos organo-fosforados - malation, folition e temefos -e dois piretroides sintéticos - alfametrina e deltametrina - foram usados para controlar o estado da susceptibilidade das larvas e adultos de seis mosquitos vetores na Índia. Foram utilizadas cepas de laboratório e área de Culex quinquefasciatus (filariasis e Aedes albopictus (Dengue e cepas de laboratório de Aedes aegypti (Dengue, Anopheles stephensi e Anopheles culicifacies (Malária e Culex tritaenorhynchus (encefalite japonesa. Os valores de C1(50 obtidos para esses inseticidas mostram que todas as espécies incluindo as cepas de área foram muito susceptíveis. Nos

  6. Joint acute toxicity of the herbicide butachlor and three insecticides to the terrestrial earthworm, Eisenia fetida.

    Science.gov (United States)

    Wang, Yanhua; Cang, Tao; Yu, Ruixian; Wu, Shenggan; Liu, Xinju; Chen, Chen; Wang, Qiang; Cai, Leiming

    2016-06-01

    The herbicide butachlor and three insecticides phoxim, chlorpyrifos, and lambda-cyhalotrhin are widely used pesticides with different modes of action. As most previous laboratory bioassays for these pesticides have been conducted solely based on acute tests with a single compound, only limited information is available on the possible combined toxicity of these common chemicals to soil organisms. In this study, we evaluated their mixture toxicity on the terrestrial earthworm, Eisenia fetida, with binary, ternary, and quaternary mixtures. Two different types of bioassays were employed in our work, including a contact filter paper toxicity test and a soil toxicity test. Mixture toxicity effects were assessed using the additive index method. For all of the tested binary mixtures (butachlor-phoxim, butachlor-chlorpyrifos, and butachlor-lambda-cyhalothrin), significant synergistic interactions were observed after 14 days in the soil toxicity assay. However, greater additive toxicity was found after 48 h in the contact toxicity bioassay. Most of the ternary and quaternary mixtures exhibited significant synergistic effects on the worms in both bioassay systems. Our findings would be helpful in assessing the ecological risk of these pesticide mixtures to soil invertebrates. The observed synergistic interactions underline the necessity to review soil quality guidelines, which are likely underestimating the adverse combined effects of these compounds.

  7. Oximes in organophosphorus poisoning

    Directory of Open Access Journals (Sweden)

    Cherian M

    2005-01-01

    Full Text Available Acute organic insecticide poisoning is a major health problem all over the world, particularly in the developing countries, where organophosphates (OPs are the most common suicidal poisons with high morbidity and mortality and account for a large proportion of patients admitted to intensive care units. Other insecticides less commonly used are organocarbamates, organochlorides, and pyrethroids, which are less toxic and are associated with less morbidity and mortality. Patients with poisoning present with a wide spectrum of gastrointestinal, neurological, and cardiac manifestations. A strong clinical suspicion is necessary to make an early diagnosis and to start appropriate therapy. Treatment is primarily supportive and includes decontamination, anticholinergics, protection of the airway, and cardiac and respiratory support. The use of oximes has been controversial and may be associated with higher mortality owing to a higher incidence of type-II paralysis. They may have other toxic side effects. This paper reviews the literature on OP poisoning.

  8. Organophosphorus agent induced delayed neuropathy: a case report

    Directory of Open Access Journals (Sweden)

    Harshit Acharya

    2016-02-01

    Full Text Available A 40-year old male, was presented with complaint of difficulty in walking with inability to flex foot and toes in bilateral feet ( and ldquo;foot drop and rdquo;, which was acute at the onset and gradually progressive since the past 7 days. The patient's wife and their 2 children had similar complaint with the same period of onset. At home, his family used cottonseed oil as cooking oil with wheat grain mixed with castor oil. On neurological examination, he was found to have lower motor neuron weakness with spasticity. After ruling out other common causes of polyneuropathy and lower motor weakness; due to high suspicion of poisoning by food adulterant, RBC acetyl cholinesterase (AChE and plasma cholinesterase (BuChE were tested at National Institute of Occupational Health (NIOH, which came low and confirmed diagnosis of Organophosphorus (OP poisoning. Nerve conduction study was done; which showed decreased amplitude of conduction in bilateral peroneal and right tibial nerve along with decreased mean nerve conduction velocity of bilateral median nerve. Thus patient was diagnosed with organophosphorus agent induced delayed axonal type of polyneuropathy and physiotherapy was started as treatment. OP compounds are a diverse group of chemicals which are principally used as insecticides in agriculture. Following organophosphate poisoning (OPP, 3 well-defined neurological syndromes are recognised: cholinergic crisis, intermediate syndrome and delayed polyneuropathy. Some organophosphates, particularly triorthocresyl phosphate (TOCP and tricresyl phosphate (TCP, produce delayed neuropathy. On ingestion, they do not produce significant cholinergic crisis, but 7 to 20 days later it leads to a pure motor axonal neuropathy with wrist and foot drop. The mechanism may involve inhibition of neuropathy target esterase (NTE, which is found in the brain, peripheral nerves, and lymphocytes. This form of toxicity has been seen occasionally in small epidemics in

  9. Declining ring-necked pheasants in the Klamath Basin, California: I. Insecticide exposure

    Science.gov (United States)

    Grove, Robert A.; Buhler, D.R.; Henny, Charles J.; Drew, A.D.

    1998-01-01

    A study of organophosphorus (OP) insecticide exposure was conducted on a declining population of ring-necked pheasants (Phasianus colchicus) associated with agricultural lands at Tule Lake National Wildlife Refuge (TLNWR) during the summers of 1990a??92. Findings at TLNWR were compared with a nearby pheasant population at Lower Klamath National Wildlife Refuge (LKNWR) not subjected to intensive farming or OP insecticide applications. Direct toxicity of anticholinesterase (antiChE) compounds (in this case methamidophos) killed 2 young pheasants (91 and 92% brain acetylcholinesterase [AChE] inhibition), but no deaths of adult radio-equipped hens were ascribed to direct insecticide intoxication. However, within 20 days postspray of OP insecticides, 68% (28 of 41) of the adult pheasants collected at TLNWR were exposed to antiChE insecticides, and exhibited brain AChE inhibition of 19a??62%, with 15% (6 of 41) showing >55% brain AChE inhibition. The lack of radio-equipped hens dying was unexpected because >50% brain AChE inhibition has been frequently used as a diagnostic tool for evaluating cause of death from antiChE insecticides. No young were radio-equipped, so the extent of the effects of insecticide exposure on the survivorship of young was unknown. It is concluded that insecticide exposure was not the major factor impacting the pheasant population (see Grove et al., in press), although some young were acutely intoxicated. However, the loss of insects killed by insecticide use may have contributed to food shortages of young pheasants, indirectly influencing survival.

  10. Clinical Observation Hemoperfusion Treatment of Acute Severe Organophosphorus Pesticide Poisoning%血液灌流治疗急性重度有机磷农药中毒的临床观察

    Institute of Scientific and Technical Information of China (English)

    王旭亮

    2013-01-01

    Objective To evaluate the hemoperfusion treatment of acute severe organophosphorus pesticide poisoning (acute severe organophosphorous pesticide poisoning). Methods from August 2009 to December 2012, our department treated 40 cases of acute severe organophosphorus pesticide, in conventional medical treatment with hemoperfusion treatment of 21 cases as treatment group,for only given conventional medical treatment 19 cases as control group. Results In comparison with control group, patients in treatment group needed shorter time for waking from coma, shorter recovery time of cholinesterase activity and shorter time for hospitalization, and intermediate syndrome incidence decline in this group were reduced (P<0.01). Moreover ,total dose of atropine applied in treatment group were lower (P<0.01), and fatality rate were lower in this group (P<0.05). Conclusion the hemoperfusion can quickly remove toxins in the body and can improve the rescue success rate in patients with acute severe organophosphorus pesticide poisoning.%目的探讨血液灌流治疗急性重度有机磷农药中毒(acute severe organophosphorous pesticide poisoning)的效果。方法2009年08月~2012年12月我科收治急性重度有机磷农药40例,对在常规内科治疗上加用血液灌流治疗的21例作为治疗组,对仅给予常规内科治疗的19例作为对照组。结果治疗组和对照组比较,患者昏迷至清醒时间、胆碱酯酶活力恢复时间、住院时间明显缩短,中间综合征发生率下降,应用阿托品总量减少(P均<0.01),病死率降低(P<0.05)。结论血液灌流能迅速清除体内毒物,可提高急性重度有机磷农药中毒患者抢救成功率。

  11. A rapid spectrophotometric assay of some organophosphorus pesticide residues in vegetable samples

    Science.gov (United States)

    Mathew, Sunitha B.; Pillai, Ajai K.; Gupta, Vinay K.

    2007-08-01

    A rapid and sensitive spectrophotometric method for the determination of some organophosphorus insecticides, i.e. malathion, dimethoate and phorate is described. It is based on the oxidation of organophosphorus pesticide with slight excess of N-bromosuccinimide (NBS) and the unconsumed NBS is determined with rhodamine B (lambda max: 550 nm). Beer's law is obeyed in the concentration range 0.108-1.08, 0.056-0.56 and 0.028-0.28 μg mL -1 for malathion, phorate and dimethoate, respectively. The method has been successfully applied for the determination of organophosphorus pesticide residues in various vegetable samples.

  12. High lethality and minimal variation after acute self-poisoning with carbamate insecticides in Sri Lanka – implications for global suicide prevention

    Science.gov (United States)

    Lamb, Thomas; Selvarajah, Liza R.; Mohamed, Fahim; Jayamanne, Shaluka; Gawarammana, Indika; Mostafa, Ahmed; Buckley, Nicholas A.; Roberts, Michael S.; Eddleston, Michael

    2016-01-01

    Abstract Background: Highly hazardous organophosphorus (OP) insecticides are responsible for most pesticide poisoning deaths. As they are removed from agricultural practice, they are often replaced by carbamate insecticides of perceived lower toxicity. However, relatively little is known about poisoning with these insecticides. Methods: We prospectively studied 1288 patients self-poisoned with carbamate insecticides admitted to six Sri Lankan hospitals. Clinical outcomes were recorded for each patient and plasma carbamate concentration measured in a sample to confirm the carbamate ingested. Findings: Patients had ingested 3% carbofuran powder (719), carbosulfan EC25 liquid (25% w/v, 389), or fenobucarb EC50 liquid (50% w/v, 127) formulations, carbamate insecticides of WHO Toxicity Classes Ib, II, and II, respectively. Intubation and ventilation was required for 183 (14.2%) patients while 71 (5.5%) died. Compared with carbofuran, poisoning with carbosulfan or fenobucarb was associated with significantly higher risk of death [carbofuran 2.2%; carbosulfan 11.1%, OR 5.5 (95% CI 3.0–9.8); fenobucarb 6.3%, OR 3.0 (1.2–7.1)] and intubation [carbofuran 6.1%; carbosulfan 27.0%, OR 5.7 (3.9–8.3); fenobucarb 18.9%, OR 3.6 (2.1–6.1)]. The clinical presentation and cause of death did not differ markedly between carbamates. Median time to death was similar: carbofuran 42.3 h (IQR 5.5–67.3), carbosulfan 21.3 h (11.5–71.3), and fenobucarb 25.3 h (17.3–72.1) (p = 0.99); no patients showed delayed onset of toxicity akin to the intermediate syndrome seen after OP insecticide poisoning. For survivors, median duration of intubation was 67.8 h (IQR 27.5–118.8) with no difference in duration between carbamates. Reduced GCS at presentation was associated with worse outcome although some patients with carbosulfan died after presentation with normal GCS. Conclusions: We did not find carbamate insecticide self-poisoning to vary markedly according to the carbamate

  13. Investigations on Blood Activities of Some Enzymes in Dogs After Acute Intoxication with the Carbamate Insecticide Carbofuran

    Directory of Open Access Journals (Sweden)

    Rumen Binev

    2016-10-01

    Full Text Available Experiments for monitoring of changes in blood enzyme activities were carried out in dogs after acute intoxication with the carbamate insecticide carbofuran (Carbosan 35 СТ. The studies involved one control and 6 experimental groups of dogs (total n=42, treated once orally with increasing doses of the preparation via oesophageal probe: 0.525 mg/kg (experimental group I, 1.05 mg/kg (experimental group II, 2.1 mg/kg (experimental group III, 3.5 mg/kg (experimental group IV, 5.25 mg/kg (experimental group V and 10.5 mg/kg (LD50, (experimental group VI, corresponding to 1/20, 1/10, 1/5, 1/3, 1/2 and LD50, oral doses for albino rats. Blood samples were obtained from v. antebrachi cephalica or v. jugularis in the course of 3 consecutive days prior to the treatment (hours -48, -24 and 0 and on post treatment hours 1, 3, 5, 7, 24 and 48 from all groups for analysis of acetylcholinesterase (AChE, aspartate aminotransferase (ASAT, alanine aminotransferase (ALAT, amylase (AMY, gamma-glutamyltransferase (g-GT, alkaline phosphatase (ALP and lactate dehydrogenase (LDH. It was established that the tested carbamate insecticide provoked lower blood activity of AChE and increased the levels of ASAT, ALAT, AMY, g-GT, AP and LDH between post treatment hours 1 and 7; afterwards, the studied parameters regained the respective control values.

  14. The characteristics of emergency department presentations related to acute herbicide or insecticide poisoning in South Korea between 2011 and 2014.

    Science.gov (United States)

    Moon, Jeong Mi; Chun, Byeong Jo; Cho, Yong Soo

    2016-01-01

    The aim of this study was to examine epidemiologic data regarding acute herbicide or insecticide poisoning in adults from 2011 to 2014 at the national level in South Korea. Further, the association between governmental regulations involving pesticides and changes in pesticide poisoning occurrences over time was determined. Data were obtained from the emergency department (ED)-based Injury In-depth Surveillance system conducted by the Korea Center for Disease Control and Prevention (KCDC). Governmental regulations on pesticides were downloaded from the homepage of the Korea Rural Development Administration. Pesticides were classified according to guidelines provided by the World Health Organization (WHO) and by the respective Resistance Action Committee (RAC). Trends in the number of ED presentations and case fatality rate (CFR) due to pesticide poisoning were investigated. The overall CFR due to poisoning from herbicides or insecticides in adults in South Korea was 16.8% during 2011-2014. However, CFR significantly decreased over the 4-year period. The ED presentations of paraquat (PQ) poisoning fell significantly, whereas poisoning due to glyphosate, glufosinate, or combined herbicides increased markedly over the 4 years. Between 2011 and 2013, PQ was the most common pesticide poisoning, whereas glyphosate became the most frequent in 2014. PQ produced the highest rate of fatality followed by endosulfan. Although the frequency of PQ poisoning decreased, which may be attributed to governmental regulations, the CFR and incidence of pesticide poisoning in adults remain a public health concern that needs to be addressed.

  15. Clinical analysis of 85 cases with acute treatment of organophosphorus pesticide poisoning%85例急性有机磷农药中毒救治的临床分析

    Institute of Scientific and Technical Information of China (English)

    朱华; 赵春秋; 钟伟

    2014-01-01

    Objective:To investigate the treatment experience of acute organophosphorus pesticide poisoning. Methods:We record the treatment process and analyze the treatment effect of the 85 patients with organophosphate poisoning who were admitted by hospital.Results:In 85 cases of patients with acute pesticide poisoning of organic phosphorus,80 cases were cured,5 deaths,the success rate was 94%.Conclusion:Thorough effective repeated gastric lavage, rapid application of anticholinergics penehyclidine hydrochloride (Changtuoning) and cholinesterase agents (pralidoxime chloride) was the key to rescue the patients who with critical acute organophosphorus pesticide poisoning and we found that active prevention of complications occurrence can improve the success rate.%目的:探讨急性有机磷农药中毒的救治经验与体会。方法:对85例有机磷农药中毒患者的治疗过程进行记录,分析治疗效果。结果:85例急性有机磷农药中毒患者,救治成功80例,死亡5例,成功率94%。结论:急性有机磷农药中毒的抢救关键是尽快、彻底、有效反复地洗胃,快速应用抗胆碱药盐酸戊乙奎醚(长托宁)及胆碱酯酶复能剂(氯磷定),积极预防并发症的发生,可提高抢救成功率。

  16. The experience of emergency treatment on acute severe organophosphorus pesticide poisoning%急性重度口服有机磷农药中毒的急救与体会

    Institute of Scientific and Technical Information of China (English)

    张海燕

    2014-01-01

    目的:总结急性重度口服有机磷农药中毒的急救经验。方法:2011年2月-2013年12月救治急性重度口服有机磷农药中毒患者30例,对其实施救治措施。结果:本组30例患者经过救治,意识转清醒时间(1.83±1.2)天,胆碱酯酶活性恢复时间(3.2±1.6)天,住院时间(7.3±2.6)天。临床疗效:治愈29例,治愈率96.7%,死亡1例,死亡率3.3%。结论:清洗被污染的皮肤,彻底洗胃,眼污染时用微温水、2%碳酸氢钠溶液清洗,导泻,阿托品的应用以及早期足量使用氯磷定等,是急救急性重度口服有机磷农药中毒的重要措施。%Objective:To summary the experience of emergency treatment on acute severe organophosphorus pesticide poisoning. Methods:30 cases with acute severe organophosphorus pesticide poisoning were selected from February 2011 to December 2013. They were treated with first aid measures.Results:After treatment,the average time of 30 cases from consciousness turned to clear was(1.83 ± 1.2)days.Cholinesterase recovery time was(3.2 ± 1.6)days.Hospitalization time was(7.3 ± 2.6)days.Clinical curative effect:29 cases were cured,and the cure rate was 96.7%.1 cases died,and the mortality was 3.3%.Conclusion: There are important measures for emergency treatment on acute severe organophosphorus pesticide poisoning,including:washing the contaminated skin,complete gastric lavage,If eye pollution cleaning its with lukewarm water and 2% sodium bicarbonate solution,catharsis, atropine application,early and adequate use of pralidoxime chloride poisoning.

  17. Mechanical ventilation nursing of patients with respiratory failure caused by acute organophosphorus pesticide poisoning%急性有机磷农药中毒致呼吸衰竭行机械通气的护理

    Institute of Scientific and Technical Information of China (English)

    何芹香

    2012-01-01

    目的 探讨急性有机磷农药中毒致呼吸衰竭患者行机械通气的护理方法.方法 对40例急性有机磷农药中毒致呼吸衰竭患者行机械通气的护理过程及效果进行同顾性分析.结果 本组36例治愈出院,自动出院4例,抢救成功率90.0%.结论 急性有机磷农药中毒导致呼吸衰竭救治的关键是机械通气.同时加强机械通气过程中的护理,严密观察病情变化,监测和调整呼吸机参数,加强气道管理,预防感染,重视心理护理,能提高治愈率,减少并发症,促进患者早日康复.%Objective To investigate the mechanical ventilation nursing strategies for patients with respiratory failure caused by acute organophosphorus pesticide poisoning. Methods Forty patients with respiratory failure caused by acute organophosphorus pesticide poisoning received mechanical ventilation. The effect and the nursing process were analyzed retrospectively. Results A total of 36 patients were cured and discharged, and 4 patients gave up treatment. The success rate reached 90% . Conclusion The key to treat acute organophosphorus pesticide poisoning with respiratory failure is mechanical ventilation. In the course of mechanical ventilation, nursing should be intensified with a close observation of patients' conditions. The respirator parameters should be monitored and properly adjusted. The airway management should be enhanced to prevent infection. Equal attention should be paid to the psychological nursing. All of these measures can reduce complications and contribute to the early recovery of patients.

  18. 急性重度有机磷农药中毒患者死亡危险因素分析%Analysis on risk factors of mortality in patients with acute severe organophosphorus pesticide poisoning

    Institute of Scientific and Technical Information of China (English)

    孙玮艳

    2015-01-01

    Objective To explore the risk factors of mortality in patients with acute severe organophosphorus pesticide poisoning. Methods Forty-four patients with acute severe organophosphorus pesticide poison were retrospectively analyzed.Various risk factors were statistically evaluated and mortality of patients was compared between groups.Results Hospital mortality in 44 patients with acute severe organophosphorus pesticide poisoning was 22.7%.The mortality was significantly different between APACHE Ⅱ score ≥20 group and APACHE Ⅱ score<20 group (P <0.01),between age ≥ 60 group and age< 60 group (P <0.01),between hypotensive group and non-hypotensive group (P < 0.05 ),between hypoxemia group and non-hypoxemia group (P < 0.05 ),between metabolic acidosis group and non-metabolic acidosis group (P < 0.05 ).Conclusion APACHE Ⅱ score,age, hypotension, hypoxemia, metabolic acidosis may be the risk factors of mortality in patients with acute organophosphorus pesticide poisoning,and the items can be used to assess the severity of disease and mortality risk in clinic.%目的:探讨急性重度有机磷农药中毒死亡的危险因素。方法回顾性分析急性重度有机磷农药中毒44例患者的临床资料,对各项危险因素进行统计分析,比较患者的病死率。结果44例急性重度有机磷农药中毒患者住院期间病死率22.7%(10/44),其中急性生理学及慢性健康状况评分(APACHE)≥20分和<20分、年龄≥60岁和<60岁、合并低血压和未合并低血压、合并低氧血症和未合并低氧血症、合并代谢性酸中毒和未合并代谢性酸中毒的患者病死率比较,差异均有统计学意义(P <0.05或<0.01)。结论 APACHEⅡ分值、高龄、低血压、低氧血症、代谢性酸中毒可能是急性重度有机磷农药中毒患者死亡的危险因素,在临床中可以用于评估患者病情严重程度与死亡风险。

  19. Study on the best marker for myocardial damage of acute organophos-phorus pesticide poisoning%急性有机磷农药中毒心肌损伤最佳标志物的研究

    Institute of Scientific and Technical Information of China (English)

    陈士轩; 滕哈乐; 牛红霞; 褚晓雯; 黄金洪; 肖青; 夏于新; 韩颖

    2015-01-01

    Objective To explore the best marker for myocardial injury after 6 hours of acute organophosphorus pesti-cide poisoning (AOPP). Methods 86 cases of AOPP patients in Department of Emergency, Electric Power Teaching Hospital of Capital Medical University ("our hospital"for short) from May 2006 to November 2014 were selected as ob-servation group. They were divided into mild poisoning group, moderate poisoning group and severe poisoning group ac-cording to the Occupational Acute Organophosphorus Pesticide Poisoning (GBZ8-2002). All patients were routinely done for 12 lead ECG examination and examined for CK, CK-MB, cTnI in 6 hours after taking poison. Control group was from our hospital outpatient health examination, and CK, CK-MB, cTnI levels were examined the same day. The above three indicators of each group were observed. Results There were statistical differences in CK, CK-MB, cTnI levels between observation group and control group (P 0.05), and there was statistical difference in cTnI level be-tween mild poisoning group and control group (P 0.05). There was statistical difference in CK-MB level between severe poisoning group and moderate poisoning group (P0.05),cTnI水平差异有统计学意义(P0.05),CK-MB水平差异有统计学意义(P<0.05),cTnI水平差异有高度统计学意义(P<0.01)。结论cTnI是判断AOPP心肌损伤的最敏感指标,是AOPP心肌损伤的最佳标志物,CK-MB次之。 CK和心电图对判断AOPP心肌损伤及损伤程度价值不大。

  20. [Today's threat of use of organophosphorus compounds].

    Science.gov (United States)

    Sokołowski, Rafał; Płusa, Tadeusz

    2015-09-01

    Organophosphates are stable cholinesterases inhibitors (AChE). Inhibition of AChE activity leads to the accumulation of large amounts of acetylcholine and hyperactivity of the cholinergic system by stimulating acetylcholine receptors - muscarinic and nicotinic. This group included tabun, sarin, soman and VX gases. Exposure to gaseous form causes symptoms within a few seconds of exposure. This depends on the gas concentration in the atmosphere. The most sensitive organ is the eyes and the respiratory system. Severe poisoning are characterized by the immediate loss of consciousness with convulsions. Therapeutic management of acute poisoning organophosphorus compounds boils down to treating symptomatic and supportive vital functions. Monitoring of cardiovascular, respiratory and renal failure in intensive care gives only guarantee the effective treatment of poisoning. Properties toxic organophosphorus compounds also are of interest to terrorist groups.

  1. Highly Strained Organophosphorus Compounds

    NARCIS (Netherlands)

    Slootweg, J.C.

    2005-01-01

    In our research on small, strained organophosphorus ring systems we became interested in the synthesis and applications of species that are even more strained than the parent phosphirane, by introducing an exocyclic double bond (methylenephosphirane), and by cyclopropyl spirofusion to the edge (e.g

  2. Acute contact toxicity test of insecticides (Cipermetrina 25, Lorsban 48E, Thionex 35) on honeybees in the southwestern zone of Uruguay.

    Science.gov (United States)

    Carrasco-Letelier, Leonidas; Mendoza-Spina, Yamandú; Branchiccela, María Belén

    2012-07-01

    Glyphosate-resistant soybean cultivation is expanding rapidly in Uruguay, with its land area having increased by 95 times during the past 10 years. Because of the region's Neotropical conditions, insecticide use is required to ensure adequate soybean productivity. However, in areas shared by soybean crops and beekeepers - such as the southwestern zone of Uruguay (SWZU) - the use of insecticides can increase the risks of honeybee death and honey contamination. Uruguayan commercial and legal guidelines set out practices and field doses designed to prevent acute intoxication with insecticides. However, honeybees in the SWZU are predominantly a polyhybrid subspecies different from that used to set international reference values, and hence they may have a different acute toxicity response, thus rendering such precautions ineffective. The aim of this work was to assess the acute toxicity response of polyhybrid honeybees in the SWZU to cypermethrin (commercial formulation: Cipermetrina 25 Agrin®), chlorpyrifos (commercial formulation: Lorsban 48E®), and endosulfan (commercial formulation: Thionex 35®). Acute toxicity bioassays were conducted to determine the median lethal dose (LD(50)) of each insecticide for the honeybees. The results indicate that, compared with EU reference values, SWZU honeybees have a higher toxicological sensitivity to chlorpyrifos and endosulfan, and a lower toxicological sensitivity to cypermethrin, based on the commercial formulations tested. However, when these results were adjusted according to their field dose equivalents, only chlorpyrifos emerged as a potential problem for beekeeping, as the maximum recommended field dose of Lorsban 48E® for soybean crops in Uruguay is 23 times the corresponding LD(50) for honeybees in the SWZU.

  3. Acute and reproductive effects of Align, an insecticide containing azadirachtin, on the grape berry moth, Lobesia botrana.

    Science.gov (United States)

    Irigaray, F Javier Sáenz-De-Cabezón; Moreno-Grijalba, Fernando; Marco, Vicente; Pérez-Moreno, Ignacio

    2010-01-01

    Azadirachtin, derived from the neem tree, Azadirachta indica A. Juss (Sapindales: Meliaceae), seems promising for use in integrated pest management programs to control a variety of pest species. A commercial formulation of azadirachtin, Align, has been evaluated against different developmental stages of the European grape berry moth, Lobesia botrana Denis and Schiffermüller (Lepidoptera: Tortricidae). When administered orally, Align reduced the fecundity and fertility of adults treated with 1, 5, and 10 mg litre(-1). At the highest doses, fecundity and fertility were zero, but longevity was not affected. An LC(50) of 231.5 mg litre(-1) was obtained when Align was sprayed on eggs less than 1 day old. Hatching of all egg classes was significantly reduced, and this reduction was more pronounced for eggs less than 24 h old. LC(50) values of 2.1 mg litre(-1) for first instars and 18.7 mg litre(-1) for third instars were obtained when Align was present in the diet. Larvae reared on a diet containing different concentrations of Align did not molt into adults at the highest concentrations (0.3, 0.6, 1.2), and 50% molted at the lowest concentration (0.15). Phenotypic effects included inability to molt properly and deformities. The combination of acute toxicity and low, effective concentrations of Align observed in this study could lead to the inclusion of insecticides containing azadirachtin in integrated management programs against this pest.

  4. Anticholinesterase insecticide retrospective.

    Science.gov (United States)

    Casida, John E; Durkin, Kathleen A

    2013-03-25

    The anticholinesterase (antiChE) organophosphorus (OP) and methylcarbamate (MC) insecticides have been used very effectively as contact and systemic plant protectants for seven decades. About 90 of these compounds are still in use - the largest number for any insecticide chemotype or mode of action. In both insects and mammals, AChE inhibition and acetylcholine accumulation leads to excitation and death. The cholinergic system of insects is located centrally (where it is protected from ionized OPs and MCs) but not at the neuromuscular junction. Structural differences between insect and mammalian AChE are also evident in their genomics, amino acid sequences and active site conformations. Species selectivity is determined in part by inhibitor and target site specificity. Pest population selection with OPs and MCs has resulted in a multitude of modified AChEs of altered inhibitor specificity some conferring insecticide resistance and others enhancing sensitivity. Much of the success of antiChE insecticides results from a suitable balance of bioactivation and detoxification by families of CYP450 oxidases, hydrolases, glutathione S-transferases and others. Known inhibitors for these enzymes block detoxification and enhance potency which is particularly important in resistant strains. The current market for OPs and MCs of 19% of worldwide insecticide sales is only half of that of 10 years ago for several reasons: there have been no major new compounds for 30 years; resistance has eroded their effectiveness; human toxicity problems are still encountered; the patents have expired reducing the incentive to update registration packages; alternative chemotypes or control methods have been developed. Despite this decline, they still play a major role in pest control and the increasing knowledge on their target sites and metabolism may make it possible to redesign the inhibitors for insensitive AChEs and to target new sites in the cholinergic system. The OPs and MCs are down

  5. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Shuyan; Chen, Yao [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Wang, Daosheng [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Hua, Rimao, E-mail: rimaohua@ahau.edu.cn [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Tang, Xinyun [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Li, Qing X. [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East–West Road, Honolulu, HI 957822 (United States)

    2015-10-30

    Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.

  6. Organophosphorus Compounds in Organic Electronics.

    Science.gov (United States)

    Shameem, Muhammad Anwar; Orthaber, Andreas

    2016-07-25

    This Minireview describes recent advances of organophosphorus compounds as opto-electronic materials in the field of organic electronics. The progress of (hetero-) phospholes, unsaturated phosphanes, and trivalent and pentavalent phosphanes since 2010 is covered. The described applications of organophosphorus materials range from single molecule sensors, field effect transistors, organic light emitting diodes, to polymeric materials for organic photovoltaic applications.

  7. Fatty acid amide hydrolase inhibition by neurotoxic organophosphorus pesticides.

    Science.gov (United States)

    Quistad, G B; Sparks, S E; Casida, J E

    2001-05-15

    Organophosphorus (OP) compound-induced inhibition of acetylcholinesterase (AChE) and neuropathy target esterase explains the rapid onset and delayed neurotoxic effects, respectively, for OP insecticides and related compounds but apparently not a third or intermediate syndrome with delayed onset and reduced limb mobility. This investigation tests the hypothesis that fatty acid amide hydrolase (FAAH), a modulator of endogenous signaling compounds affecting sleep (oleamide) and analgesia (anandamide), is a sensitive target for OP pesticides with possible secondary neurotoxicity. Chlorpyrifos oxon inhibits 50% of the FAAH activity (IC50 at 15 min, 25 degrees C, pH 9.0) in vitro at 40--56 nM for mouse brain and liver, whereas methyl arachidonyl phosphonofluoridate, ethyl octylphosphonofluoridate (EOPF), oleyl-4H-1,3,2-benzodioxaphosphorin 2-oxide (oleyl-BDPO), and dodecyl-BDPO give IC50s of 0.08--1.1 nM. These BDPOs and EOPF inhibit mouse brain FAAH in vitro with > or =200-fold higher potency than for AChE. Five OP pesticides inhibit 50% of the brain FAAH activity (ED50) at diazinon, and methamidophos occurs near acutely toxic levels, profenofos and tribufos are effective at asymptomatic doses. Two BDPOs (dodecyl and phenyl) and EOPF are potent inhibitors of FAAH in vivo (ED50 0.5--6 mg/kg). FAAH inhibition of > or =76% in brain depresses movement of mice administered anandamide at 30 mg/kg ip, often leading to limb recumbency. Thus, OP pesticides and related inhibitors of FAAH potentiate the cannabinoid activity of anandamide in mice. More generally, OP compound-induced FAAH inhibition and the associated anandamide accumulation may lead to reduced limb mobility as a secondary neurotoxic effect.

  8. Acute toxicity of several organophosphorous insecticides and protection by cholinergic antagonists and 2-PAM on Artemia salina larvae.

    Science.gov (United States)

    Sánchez-Fortún, S; Sanz, F; Barahona, M V

    1996-10-01

    The acute toxicity of chlorpyrifos, methylchlorpyrifos, parathion and methylparathion to three age classes of Artemia salina was determined. In general, A. salina 24-h old was less sensitive to these organophosphorous insecticides (OPI) than A. salina 48-h old and A. salina 48-h old was significantly more tolerant than A. salina 72-h old, in contrast, chlorpyrifos was equally toxic to A. salina 48- and 72-h old. There were some differences among the three age classes of A. salina in the relative order of toxicity of OPI tested. The rank order of toxicity to A. salina 48-h old was methylparathion salina 24- and 72-h old it was methylparathion = parathion Artemia salina 24-h old was investigated. The lethal action of OPI tested was completely prevented by pretreatment of Artemia salina 24-h old with 2-PAM (10(-5) M) and atropine (10(-4 )M). However no concentration of hexamethonium, pirenzepine or AF-DX 116 protected 100% of the animals poisoned by LC84 of the OPI selected, maximum protection obtained was 71 to 88%. In contrast, the maximum inhibition of mortality obtained with AF-DX 116 pretreatment was about 55% because this compound was used at concentrations which were non toxic to control Artemia salina. Atropine, hexamethonium, pirenzepine, AF-DX 116 and 2-PAM afforded 50 % protection (IC50) of Artemia salina against mortality by LC84 of the OPI selected at concentrations in the range of 6.62x10(-7)-1.6x10(-6) M, 2. 38x10(-4)-2.05x10(-3)M, 8.91x10(-7)-1.24x10(-6) M, 9.66x10(-8)-1. 34x10(-7 )M, and 1.95x10(-8)-2.73x10(-8 )M, respectively. Pretreatment of atropine plus 2-PAM to determine whether this combination afforded greater inhibition of the lethality induced by four OPI tested than pretreatment with either atropine or 2-PAM alone was investigated. Atropine (10(-5) M) in combination with 2-PAM (10(-7 )M) inhibited completely the acute toxicity of all OPI tested, while the pretreatment with atropine (10(-6) M) plus 2-PAM at the same concentration gave a

  9. Oxidative stress and cytotoxic potential of anticholinesterase insecticide, malathion in reproductive toxicology of male adolescent mice after acute exposure

    Directory of Open Access Journals (Sweden)

    Selmi Slimen

    2014-07-01

    Conclusion: The importance to carry out in vitro reproductive toxicology assays lies on the need of knowing the alterations these insecticides may cause at cellular level, since they are endocrine disruptors that interfere with reproductive functions.

  10. The insecticide resistance in stripped stem borer, Chilo suppressalis (Walker)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The stripped stem borer (SSB), Chilo suppressalis (Walker) is one of the major insect pests of rice in China. Chemical control has been a common practice in SSB management since 1950s. Insecticides used included BHC before 1983;organophosphorus insecticides (methyl-parathion, trichophon, methamidophos, and monocrotophos), and chlordimeform in mid-1970s-1980s; Shachongshuang (dimehypo) and Shachongdan (monousltap) since early 1980s. In recent years, SSB population and its damage to rice increased rapidly and failures on control has been reported. To find out the cause of failure and to put forward the suitable control methods, we studied the resistance of SSB to major insecticides used in China.

  11. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1.

    Science.gov (United States)

    Deng, Shuyan; Chen, Yao; Wang, Daosheng; Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong; Hua, Rimao; Tang, Xinyun; Li, Qing X

    2015-10-30

    Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.

  12. Study of Serum Amylase and Serum Cholinesterase in Organophosphorus Poisoning

    Directory of Open Access Journals (Sweden)

    Sharan Badiger

    2016-04-01

    Full Text Available Background: Poisoning due to organophosphorus compounds is most commonly seen. Earlier plasma cholinesterase level was used to assess the severity of poisoning. Presently serum amylase is being recommended as a better indicator of severity. Aims and Objectives: To study plasma cholinesterase and serum amylase levels in acute organophosphorus and to correlate serum amylase levels with clinical severity and outcome. Material and Methods: A total of 80 patients in the study admitted to a tertiary care centre within 24 hours with a history of organophosphorus poisoning were included in study. Estimation of plasma cholinesterase and serum rd amylase was done at the time of admission, and on 3 th day and on 5 day. Results: Occurrence of organophosphorus poisoning was more common among age group 21-30 years and among males (57.5%. They were 25 (31.2% farmers, 23 (28.8% st u d e n ts, a n d 2 2 ( 2 7 . 5% h o u s ewi v e s. Monocrotophos (45.0% was commonly used compound. Mean value of plasma cholinesterase and serum amylase at admission are 3693 U/L, and 185.4 U/L. There was significant inhibition of plasma cholinesterase and elevation of serum amylase at th admission with return to normal values on 5 day. Conclusion: Plasma cholinesterase inhibition 200 U/L has been associated with poor prognosis and proneness to respiratory failure.

  13. Human Paraoxonase Double Mutants Hydrolyze V and G Class Organophosphorus Nerve Agents

    Science.gov (United States)

    2013-01-01

    induced by seizures. Traditional pharmacological approaches to alleviate the effects of OP poisoning have reached a point where only modest incremental...using Prism 4.0 (GraphPad, La Jolla, CA). 3. Results and discussion Organophosphate insecticides like paraoxon are helpful in quickly determining OP...therapy of organophosphorus poisoning , Toxicology 233 (2007) 47–49. [5] M. Harel, A. Aharoni, L. Gaidukov, B. Brumshtein, O. Khersonsky, R. Meged, H. Dvir

  14. 17 cases of organophosphorus pesticide poisoning combined with acute pancreatitis%有机磷农药中毒并发急性胰腺炎17例

    Institute of Scientific and Technical Information of China (English)

    蔡海英; 张茂

    2010-01-01

    @@ 急性有机磷农药中毒(acute organophosphorous pesticides poisoning,AOPP)是急诊科较为常见的急症之一,尤其在基层医院更为多见.中、重度AOPP病情变化较多,并发神经、心脏及呼吸系统损害较为常见且报道较多,但对并发胰腺炎往往不被认识,容易导致误诊和漏诊,从而延误治疗甚至危及生命.

  15. 急性有机磷中毒临床综合治疗分析%The combined therapy of acute organophosphorus pesticide poisoning clinical observation

    Institute of Scientific and Technical Information of China (English)

    丁宗发; 伍松涛

    2011-01-01

    Objective:To study on acute organophosphate poisoning of clinical characteristic and clinical treatment Methods; A retrospective analysis of 55 cases in our hospital with acute organophosphate pesticide poisoning patients with clinical data from JAN 20005 to JAN 2010. Observe the clinical characteristics. Results: 55 cases with acute organophosphate poisoning pass a system comprehensive treatment of the cure rate reaches a percentage of 94. 55. Extensive skin contact and respiratory suction poisoning patients cure rate was a percentage of 100%, two cases death. Conclusion: Clinicians should be timely, accurate, rapid and complete gastric lavage as soon as possible, in sufficient quantities, repeated, sustained the right of use of atropine and atropine rapidly as soon as possible for the first time in sufficient quantities to use PAM, it is key to prevent complications place.%目的:探讨急性有机磷中毒的临床特点和临床诊治方法.方法:回顾性分析我院2005年1月-2010年1月救治的55例急性有机磷农药中毒患者的临床资料,观察其临床特点.结果:55例急性有机磷中毒的患者,经过系统的综合治疗治愈率达94.55%.广泛皮肤接触和呼吸道吸中毒的患者治愈率为100%,死亡2例.结论:及早、正确、快速、彻底洗胃,及早、足量、反复、特续,正确使用阿托品及快速阿托品化,及早,首次足量使用解磷,并注意患者饮食以及积极防治相关并发症等都是保障患者康复的关键.

  16. Liquid chromatography of organophosphorus acids

    NARCIS (Netherlands)

    Verweij, A.; Kientz, C.E.; Berg, J. van den

    1988-01-01

    The applicability of different liquid chromatographic systems such as ion-exchange, ion-exclusion, reversed phase and ion-pair partition was studied for the analysis of a number of simple structurally related organophosphorus acids which lack a chromophoric group. Preliminary experiments based on th

  17. 急性中重度有机磷农药中毒对认知功能的影响%Effect of Acute Moderately Severe Organophosphorus Pesticides Poisoning on Cognitive Function

    Institute of Scientific and Technical Information of China (English)

    杨琴; 田仰华; 周姝; 李景荣; 程景林

    2016-01-01

    Objective To investigate the effect of acute moderately severe organophosphorus pesticides poisoning on cognitive function. Methods 29 patients with acute moderately severe organophosphorus pesticides poisoning,who had been hospitalized in Department of Emergency Internal Medicine of the Second Hospital of Anhui Medical University from November 2010 to October 2014 and met the inclusion criteria,were selected as the research group,and 29 healthy volunteers after physical examination in the same hospital during the same period were also enrolled as the control group. Patients in research group received corresponding treatment like timely gastric lavage. All patients' cognitive function were evaluated by the Montreal Cognitive Assessment(MoCA). The MoCA various dimensional score and total score of control group at the enrolling time and of research group 1 week,1 month and 6 months after treatment were compared in this study. Results The MoCA total score of 1 month and 6 months after treatment was higher than that of 1 week after treatment in the research group(P 0. 05). In the research group,the scores of naming,attention,abstraction,delayed recall and orientation of 1 month and 6 months after treatment were higher than those 1 week after treatment,and the scores of visual space and executive function and language 6 months after treatment were higher than those 1 week after treatment(P < 0. 05);the scores of visual space and executive function,attention,language,abstraction,delayed recall and orientation 6 months after treatment were higher than those 1 month after treatment(P < 0. 05). The scores of visual space and executive function,naming,attention, language,abstraction,delayed recall and orientation in the control group were higher than those in the research group 1 week after treatment(P < 0. 05);the scores of attention,language,delayed recall and orientation in the control group were higher than those in the research group 1 month after treatment(P < 0. 05

  18. Study on Immunochemical Assays for the Organophosphorus Insecticide Chlorpyrifos

    Institute of Scientific and Technical Information of China (English)

    WU Gang; HUANG Ya-li; ZHU Guo-nian; WU Hui-ming; LI Cong

    2004-01-01

    The anti-chlorpyrifos polyclonal antibodies were obtained by using the artificial immune antigen to immune in New Zealand′s white rabbits. The enzyme-tagged antibodies were prepared by coupling horseradish peroxidase (HRP) to the purified antibody with the modified sodium periodate method. The indirect competitive enzyme linked immuno-sorbent assays (ELISA) and the HRP-taggedantibodydirect ELISA (E-Ab) were established, respectively.The limit of detection (LOD) for the indirect ELISA and E-Ab were 0.0033 and 0.0042 μg mL-1, respectively. The linear detection ranged well from 0.005 to 2.0 μg mL-1.

  19. 28 Cases of Delayed Polyneuropathy Acute Induced by Organophosphorus Pesticide Poisoning%急性有机磷农药中毒致迟发性多发性神经病28例分析

    Institute of Scientific and Technical Information of China (English)

    傅继荣; 史家安

    2009-01-01

    目的 探讨急性有机磷农药中毒后迟发性多发性神经病的临床特点、发病机制,以提高早期诊断及治疗效果.方法 回顾28例迟发性多发性神经病发生的时间、症状及体症,结合辅助检查,进行系统分析.结果 28例迟发性多发性神经病患者均为口服中毒,潜伏期为10~32 d,平均18 d.主要表现为肢体末端开始的感觉和运动障碍,表现为疼痛、麻木、无力、肌肉萎缩、腱反射减弱或消失,肌电图示神经源性损害.用糖皮质激素、B族维生素等综合治疗,大部分预后良好.结论 迟发性多发性神经病经早期诊断,积极治疗,预后一般良好,激素治疗可加速神经功能恢复.%Objective To explore the clinical features and pathogenesis of the delayed polyneuropathy induced by acute organ-ophosphorus pesticide poisoning,and improve the curative effects of early diagnosis and treatment. Methods The onset time,symptoms and physical signs of 28 eases of delayed polyneuropathy were recalled and analyzed combined with supplementary ex-amination retrospectively. Results 28 delayed polyneuropathy were all oral poisoning, the incubation period was of 10 to 32 days, with an average of 18 days. Dyskinesia and abnormity of sense started from the end of limbs, such as pain, numbness, weak-ness, muscle atrophy, weakening or disappearance of tendon reflexes, neurogenie damage showed by electromyography, were the main clinical manifestation. The comprehensive treatment with glueocortieoid and B vitamins eould improve prognosis.Conclusion The delayed polyneuropathy has a good prognosis by early diagnosis and active treatment, and hormone therapy may accelerate the recovery of neurological function.

  20. 高压氧对动物有机磷中毒后神经损害恢复的实验研究%Effect of hyperbaric oxygen on nerve impairment recovery of animals after organophosphorus: an experimental study

    Institute of Scientific and Technical Information of China (English)

    林忠豪; 张鸣春; 肖鹏

    2002-01-01

    Objective To investigate the effect of hyperbarci oxygen(HBO) on recovery of nerves injury in rats suffered from acute organophosphorus poisoning. Method We established organophosphorus poisoning models and observed effect of HBO on recovery of injure nerves. Results Compared with control group, cerebrospinal fluid induced peak potential and incubation period in HBO group were significantly recovered(P<0.05).HBO could accelerated repair of injured nerves. Conclusion HBO could relieve injury of nerves during treatment of organophosphorus poisoning. ``

  1. Mixed function oxidases and insecticide resistance in medically important insects

    OpenAIRE

    2006-01-01

    MFOs are a large diverse superfamily of enzymes found in all insect tissues. They are involved in the metabolism of xenobiotics (e.g. drugs, pesticides and plant toxins) and endogenous compounds (e.g. ecdysteroids and juvenile hormones). They are also involved in bioactivation of phosphorothioate compounds such as organophosphorus insecticides. They have very diverse activities like hydroxylation, epoxidation, N-, O-or S-dealkylation, deamination, sulfoxidation, desulfuration and oxidative de...

  2. Comparison of two commonly practiced atropinization regimens in acute organophosphorus and carbamate poisoning, doubling doses vs. ad hoc: a prospective observational study.

    Science.gov (United States)

    Perera, P M S; Shahmy, S; Gawarammana, I; Dawson, A H

    2008-06-01

    There is a wide variation and lack of evidence in current recommendations for atropine dosing schedules leading to subsequent variation in clinical practice. Therefore, we sought to examine the safety and effectiveness of a titrated vs. ad hoc atropine treatment regimen in a cohort of patients with acute cholinesterase inhibitor pesticide poisoning. A prospective cohort study was conducted in three district secondary referral hospitals in Sri Lanka using a structured data collection form that collected details of clinical symptoms and outcomes of cholinesterase inhibitor pesticide poisoning, atropine doses, and signs of atropinization. We compared two hospitals that used a titrated dosing protocol based on a structured monitoring sheet for atropine infusion with another hospital using an ad hoc regime. During the study, 272 symptomatic patients with anticholinesterase poisoning requiring atropine were admitted to the three hospitals. Outcomes of death and ventilation were analyzed for all patients, 226 patients were prospectively assessed for atropine toxicity. At baseline, patients in the titrated dose cohort had clinical signs consistent with greater toxicity. This in part may be due to ingestion of more toxic organophosphates. They received less pralidoxime and atropine, and were less likely to develop features of atropine toxicity, such as delirium (1% vs. 17%), hallucinations (1% vs. 35%), or either (1% vs. 35%) and need for patient restraint (3% vs. 48%) compared with the ad hoc dose regime. After adjusting for the pesticides ingested, there was no difference in mortality and ventilatory rates between protocols. Ad hoc high dose atropine regimens are associated with more frequent atropine toxicity without any obvious improvement in patient outcome compared with doses titrated to clinical effect. Atropine doses should be titrated against response and toxicity. Further education and the use of a structured monitoring sheet may assist in more appropriate

  3. Synthesis and Computational Simulation of New Phosphorilated Sulfoximines with Insecticidal Activity

    OpenAIRE

    Licastrode, S. A.; M. E. Bellozas Reinhard

    2000-01-01

    New organophosphorus insecticides of dialkylsulphoximines derived with activity upon acetylcholinesterase were synthesized. The obtained compounds were characterized by NMR and IR, and anticholinesterase activity and toxicity was measured. A simulation through computer was done in order to establish the relationship between structure and activity.

  4. CLINICAL PATTERN AND OUTCOME OF ORGANOPHOSPHORUS COMPOUND POISONING

    Directory of Open Access Journals (Sweden)

    Ranjith Kumar

    2016-06-01

    Full Text Available BACKGROUND Organophosphate insecticides/pesticides are used widely throughout the world. The organophosphorus poisoning is a very serious condition that needs rapid treatment. Emergent and appropriate management is always desirable to prevent the serious complications and high mortality. In this study, we determine the clinical presentation and outcome of organophosphorus poisoning in our institute. MATERIAL AND METHODS This study carried out in Medicine Department, SIMS, Shimoga, from January 1st, 2016 to April 20th 2016. A total of 100 cases of OP poisoning were studied. We included all patients of organophosphate poisoning presented either with signs of muscarinic involvement or signs of nicotinic involvement. Outcome measured according to W.H.O. classification of severity. RESULT Out of a total 100 patients of organophosphate poisoning were admitted, among these 44% were males and 56% females. Average age was 28.9±8.8 years. Nausea and vomiting was the most common clinical feature found in 93% of the patients followed by salivation seen in 91% and Miosis in 87%. According to W.H.O. Classification for Severity of Organophosphate poisoning. Mild 46%, 37% cases were moderate and 17% were severe. Overall mortality rate was 19%. CONCLUSION Present study shows the importance of WHO staging of severity of organophosphorus compound poisoning as mortality increases with severity. Study also showed that delayed arrival, lack of ICU facility and lack of preliminary management at the early stage are the causes of increased mortality in OP compound poisoning. OP compound poisoning needs rapid diagnosis, early and effective treatment to decrease the severity and mortality. These finding shows need for improvement in primary health care facility to decrease morbidity and mortality

  5. Methomyl-Induced Severe Acute Pancreatitis: Possible Etiological Association

    Directory of Open Access Journals (Sweden)

    Ioannides M

    2005-03-01

    Full Text Available CONTEXT: N-methyl carbamate insecticides are widely used in homes, gardens and agriculture. They share the capacity to inhibit cholinesterase enzymes with organophosphates and therefore share similar symptomatology during acute and chronic exposures. One of the serious effects of organophosphate and carbamate intoxication is the development of acute pancreatitis and subsequent intrapancreatic fluid formation. CASE REPORT: An 18-year old Caucasian man was admitted to our Intensive Care Unit with cholinergic crisis symptomatology, after the ingestion of an unknown amount of a carbamate insecticide (methomyl. Pseudocholinesterase levels were 2 kU/L on the day of admission (reference range: 5.4-13.2 kU/L. Two days after admission, an abdominal CT scan revealed blurring of the peripancreatic fat planes, inflammation and swelling of the pancreas, and a substantial amount of ascitic fluid in the left anterior pararenal space and pelvis. Paracentesis and analysis of the ascitic fluid demonstrated findings diagnostic of pancreatic ascites. There had been no other evident predisposing factors for acute pancreatitis, other than methomyl intoxication. Eleven days after admission, pseudocholinesterase levels returned to normal, while a new abdominal CT scan revealed the formation of intrapancreatic fluid collection. The patient was discharged in good physical condition two weeks after admission. A follow up abdominal CT scan performed one month later showed a significant reduction in the size of the intrapancreatic fluid. DISCUSSION: Acute pancreatitis is not uncommon after organophosphate intoxication and carbamates share the same risk as organophosphorus pesticides. The development of acute pancreatitis and subsequent intrapancreatic fluid collection after methomyl intoxication has not previously been reported. This is the first case reported of acute pancreatitis and pancreatic ascite formation after anticholinesterase insecticide ingestion.

  6. Biodegradation of organophosphorus pesticides by soil bacteria

    Science.gov (United States)

    de Pasquale, C.; Fodale, R.; Lo Piccolo, L.; Palazzolo, E.; Alonzo, G.; Quatrini, P.

    2009-04-01

    A number of studies in the 1980s and 1990s showed that crop-protection products, applied to drained fields, could move downwards through the soil profile and to the groundwater. Organophosphorus insecticides (OPs) are used all over the world for crop protection, for other agricultural practices such as sheep dipping and, in aquaculture, for the control of sea lice. Ops besides showing a specific neurotoxicity and have also been related to various modern diseases, including Creutzfeldt-Jakob (CJD) and the Gulf War syndrome. Although OPs are less persistent than Organoclorine pesticides (OCs), they still constitute an environmental risks thus increasing the social concern about their levels in soils, surface waters, and ground waters. Degradation of OPs by microorganisms has been assessed for a few bacterial strains. In the present study the OPs degrading potential of indigenous soil microorganisms was investigated. Using enrichment cultures in which parathion was the only C and energy sources many bacterial strains were isolated from OPs contaminated and pristine agricultural soils characterized by different physico-chemical properties. More than 40 potential OPs degraders were isolated and grouped in operational taxonomic units (OTU) using analysis of polymorphism showed by the ribosomal internal transcribed spacer (ITS). Partial sequencing of 16S rRNA gene of representative isolates of each OTU revealed that most of them belong to Proteobacteria and Actinobacteria. All the analyzed soils showed the presence of putative OPs degraders: the highest diversity was found in organic cultivated soils, the lowest in chemically cultivated soils. Degradation of different OPs, characterized by different physical and chemical properties, was obtained by different selected representative strains using SPME GC-MS analysis on water and soil microcosms. The results showed that, after the incubation period, the amount of pesticide residues were in the range 20-80%. Some of the

  7. 急性有机磷农药中毒致呼吸衰竭的影响因素分析%Study on correlated clinical factors of respiratory failure induced by acute organophosphorus pesticide poisoning

    Institute of Scientific and Technical Information of China (English)

    陶贤洲; 王佐

    2014-01-01

    目的:分析急性有机磷农药中毒( AOPP)致呼吸衰竭的相关临床因素,为制订有效的预防及干预措施提供科学依据。方法回顾分析94例重性AOPP患者临床资料,根据血气分析结果将患者分为呼吸衰竭组(41例)和非呼吸衰竭组(53例),观察患者的APACHEⅡ评分、胆碱酯酶、血糖、血清淀粉酶、肝肾功能及心肌酶谱等指标。结果胆碱酯酶水平呼吸衰竭组患者低于非呼吸衰竭组患者(P<0.05);APACHEⅡ评分、血清淀粉酶、肝肾功能及心肌酶谱等,呼吸衰竭组患者高于非呼吸衰竭组患者(P<0.05);Logistic回归分析显示APACHEⅡ评分、胆碱酯酶及血清淀粉酶与呼吸衰竭相关。结论 APACHEⅡ评分、胆碱酯酶及血清淀粉酶水平可作为AOPP引起呼吸衰竭的预测指标。%Objective To investigate the correlated clinical factors of respiratory failure induced by acute organophosphorus pesticide poisoning ( AOPP) ,and to provide relevant data for prevention and intervention of respiratory failure .Methods This retrospective study in-cluded 94 patients with severe AOPP ,and all patients were divided into respiratory failure group ( n=41 ) and non-respiratory failure group (n=53) according to arterial blood gas analysis .We observed APACHEⅡscores,cholinesterase,blood glucose,serum amylase,hepatic func-tion,renal function and myocardial enzyme between the two groups .Results Cholinesterase level in the respiratory failure group was lower than that in non-respiratory failure group (P<0.05);APACHEⅡ scores,serum amylase,hepatic function,renal function and myocardial enzyme in the respiratory failure group were higher than those of non-respiratory failure group (P<0.05).Spearman correlation analysis and Logistic regression analyses showed APACHEⅡscores,cholinesterase and serum amylase were related to respiratory failure ,and they had sig-nificant predictive effects on respiratory failure

  8. Transcriptional response of rat frontal cortex following acute In Vivo exposure to the pyrethroid insecticides permethrin and deltamethrin

    Directory of Open Access Journals (Sweden)

    Tornero-Velez Rogelio

    2008-11-01

    Full Text Available Abstract Background Pyrethroids are neurotoxic pesticides that interact with membrane bound ion channels in neurons and disrupt nerve function. The purpose of this study was to characterize and explore changes in gene expression that occur in the rat frontal cortex, an area of CNS affected by pyrethroids, following an acute low-dose exposure. Results Rats were acutely exposed to either deltamethrin (0.3 – 3 mg/kg or permethrin (1 – 100 mg/kg followed by collection of cortical tissue at 6 hours. The doses used range from those that cause minimal signs of intoxication at the behavioral level to doses well below apparent no effect levels in the whole animal. A statistical framework based on parallel linear (SAM and isotonic regression (PIR methods identified 95 and 53 probe sets as dose-responsive. The PIR analysis was most sensitive for detecting transcripts with changes in expression at the NOAEL dose. A sub-set of genes (Camk1g, Ddc, Gpd3, c-fos and Egr1 was then confirmed by qRT-PCR and examined in a time course study. Changes in mRNA levels were typically less than 3-fold in magnitude across all components of the study. The responses observed are consistent with pyrethroids producing increased neuronal excitation in the cortex following a low-dose in vivo exposure. In addition, Significance Analysis of Function and Expression (SAFE identified significantly enriched gene categories common for both pyrethroids, including some relating to branching morphogenesis. Exposure of primary cortical cell cultures to both compounds resulted in an increase (~25% in the number of neurite branch points, supporting the results of the SAFE analysis. Conclusion In the present study, pyrethroids induced changes in gene expression in the frontal cortex near the threshold for decreases in ambulatory motor activity in vivo. The penalized regression methods performed similarly in detecting dose-dependent changes in gene transcription. Finally, SAFE analysis of

  9. A comparative study on the relationship between acetylcholinesterase activity and acute toxicity in Daphnia magna exposed to anticholinesterase insecticides.

    Science.gov (United States)

    Printes, Liane Biehl; Callaghan, Amanda

    2004-05-01

    Acetylcholinesterase (AChE) activity was measured in Daphnia magna that had been exposed to four organophosphates (OPs; parathion, chlorpyrifos, malathion, and acephate) and one carbamate (propoxur) for 48 h. These results were related to acute toxicity (median effective concentration [EC50] for immobility). For the four OPs, the EC50s were 7.03 pM, 3.17 pM, 10.56 pM, and 309.82 microM, respectively. The EC50 for propoxur was 449.90 pM. Reduction in AChE activity was directly related to an increase in immobility in all chemicals tested. However, the ratio between the EC50 and the AChE median inhibiting concentration ranged from 0.31 to 0.90. A 50% reduction in AChE activity generally was associated with detrimental effects on mobility. However, for acephate, high levels of AChE inhibition (70%) were observed in very low concentrations and were not associated with immobility. In addition, increasing the concentration of acephate further had a slight negative effect on AChE activity but a strong detrimental effect on mobility. Binding sites other than AChE possibly are involved in acephate toxicity to D. magna. Our findings demonstrate different associations between AChE inhibition and toxicity when different chemicals are compared. Therefore, the value of using AChE activity as a biomarker in D. magna will be dependent on the chemical tested.

  10. Pharmaceutical care for the patient with acute organophosphorous insecticides poi-soning by clinical pharmacists%临床药师在急性有机磷中毒患者治疗中的药学监护

    Institute of Scientific and Technical Information of China (English)

    伊佳; 陈万生

    2015-01-01

    目的 探讨临床药师在急性有机磷中毒患者的药学监护点,为急性有机磷中毒患者用药提供参考. 方法 临床药师通过参与急性有机磷中毒患者治疗用药方案的制定,从药物的选择、给药剂量及不良反应预计等方面,提出药学观点. 结果 治疗后,患者逐步恢复正常,未出现进一步的阿托品中毒,肝损害症状得到有效控制. 结论 临床药师参与急性有机磷中毒患者的临床治疗过程,使患者获益,提高了临床治疗水平.%Objective To discuss the pharmaceutical care for a patient with acute organophosphorous insecti-cides poisoning by clinical pharmacists,to provide references for clinical medication. Methods Clinical pharmacists participated in the formulation of medication plan for a patient with acute organophosphorous insecticides poisoning,in respects of drug selection,drug dosage and adverse drug reaction monitoring. Results After treatment,the patient re-covered gradually,and no further atropine poisoning appeared,the hepatic injury was effectively controlled. Conclusion Clinical pharmacists can participate in the treatment of patients with acute organophosphorous insecticides poisoning with obvious benefit,and enhance the level of clinical therapy.

  11. Effect of rhubarb and Glauber's salt cathartic intervention on acute organophosphorus pesticide poisoning%大黄加芒硝导泻治疗有机磷农药中毒的效果观察

    Institute of Scientific and Technical Information of China (English)

    朱茄英; 陈茶花; 鄢小莲; 肖玲; 黄敏

    2012-01-01

    Objective To investigate the effect of nasal tube feeding of rhubarb solution and umbilical compress of Glauber's salt for purgation in the treatment of patients with severe acute organophosphorus pesticide poisoning (AOPP).Methods A retrospective study was conducted.Eighty patients with severe AOPP were dividedinto two groups according to different treatment,with 40 patients in each group.A thorough gastric lavage was done,followed by cholinesterase complex agent and atropine were given for all the patients.On the base of this treatment,one group of patients were given nasogastric feeding of rhubarb solution (200 ml) and Glauber's salt solution ( 100 g) for umbilical compress (rhubarb plus Glauher group),and another group of patients were fed with 20% mannitol (200 ml)as a control group (mannitol group).The time of first defecation,number of passing stools,the time of normalization of cholinesterase (ChE) activity,time of atropinization,dosage of atropinization,and total amount of atropine given,incidence of adverse reactions,and hospital stay in two groups were observed,a statistical analysis of the data was conducted.Results In rhubarb plus Glauber group,all the conditions were improved better than those of mannitol group [first defecation time (minutes):134.13 ± 31.31 vs.154.35 ± 34.78,the number of stools (times/d):2.60 ±0.81 vs.2.14 ± 0.63,time of ChE activity returned to normal (days):9.65 ± 1.42 vs.10.66 ± 1.74,atropinization time ( hours ):3.00 ± 0.73 vs.3.56 ± 1.02,dosage of atropinization (mg):51.43 ± 7.03 vs.57.65 ± 7.74,the total amount of atropine given (mg):229.78 ± 28.96 vs.248.41 ± 31.45,the incidence of adverse reactions:abdominal pain 0 vs.17.5%,abdominal distention 0 vs.20.0%,hospital stay (days):10.43 ± 1.68 vs.11.59 ± 2.121,and all the differences were statistically significant (all P<0.01).Conclusion Combination usage with aqueous rhubarb solution and Glauber's salt in AOPP patients could yield quick clearance of toxin

  12. BIODEGRADATION OF ORGANOPHOSPHORUS PESTICIDES BY SURFACE-EXPRESSED ORGANOPHOSPHORUS HYDROLASE. (R823663)

    Science.gov (United States)

    Organophosphorus hydrolase (OPH) was displayed and anchored onto the surface ofEscherichia coli using an Lpp-OmpA fusion system. Production of the fusion proteins in membranefractions was verified by immunoblotting with OmpA antisera. inclusion of the organophosphorus...

  13. 机械通气抢救急性有机磷农药中毒呼吸衰竭47例%Rescue mechanical ventilation in acute organophosphorus pesticide poisoning with respiratory failure of 47 Cases

    Institute of Scientific and Technical Information of China (English)

    饶惠平

    2010-01-01

    目的 探讨机械通气治疗重度有机磷农药中毒呼吸衰竭的临床意义.方法 重度有机磷农药中毒呼吸衰竭患者患者83例,按是否机械通气分为治疗组47例和对照组36例.两组均常规给予洗胃、应用阿托品、氯磷定及对症支持治疗等综合措施,治疗组给予机械通气.结果 治疗组抢救成功率(89%)明显高于对照组(69%)(P<0.05).结论 早期建立人工气道机械通气是有机磷农药中毒并呼吸衰竭抢救成功的关键.%Objective To investigate the mechanical ventilation in the treatment of severe organophosphorus pesticide poisoning in the clinical significance of respiratory failure.Methods Uinical data of admitted to our hospital with severe organophosphorus pesticide poisoning respiratory failure in 83 cases were analyzed,according to whether mechanical ventilation,they were divided into treatment group(47 cases) and control group 36 cases,the efficacy were observed.Both groups were given routine gastric lavage,atropine,PAM,and symptomatic supportive care and other comprehensive measures,the treatment group,was given an extra mechanical ventilation.Results The treatment group had significantly higher success rate of resuscitation,the two groups were significantly different (P<0.05).Conclusion Early establishment of artificial airway mechanical ventilation is a key step to rescue organophosphate pesticide poisoning,and respiratory failure to rescue key.

  14. The comparison of the applications of strong ion gap, blood glucose and other indexes in the acute organophosphorus pesticide poisoning%强离子隙和血糖等指标在急性有机磷农药中毒中的应用比较

    Institute of Scientific and Technical Information of China (English)

    顾旭东; 袁雪丰; 聂时南

    2016-01-01

    目的:比较急性有机磷农药中毒( AOPP)患者的强离子隙( SIG)、血淀粉酶( AMS)、天门冬氨基酸转移酶( AST)、磷酸激酶同工酶( CK-MB)、血糖( BG)等指标与其预后的相关性。方法回顾性研究2014-01~2014-12共69例AOPP患者,根据预后分为生存组和死亡组,比较中毒早期SIG、AMS、AST、CK-MB、BG等指标水平以及其他一般资料结果,并通过分析优势比( odds ratio, OR)以及建立ROC曲线比较SIG、BG等指标对AOPP患者的预后有效性。结果异常的BG较正常的指标有更高的死亡风险,SIG较BG对致死率具有更高意义的ORs(P<0.05)。结论随着早期SIG、BG水平的升高,AOPP患者的死亡风险增加,且SIG对患者死亡预后的预测更有效。%Objective To compare the strong ion gap ( SIG) and AMS, AST, CK-MB, blood glucose ( BG) index predicting the prognosis of acute organophosphorus pesticide poisoning ( AOPP ) patients. Methods This retrospective study included 69 cases who were diagnosed by AOPP from January to December 2014. According to the prognosis they were divided into death group and survival group. By analyzing the odds ratio (ORs) and establishing ROC curve, we evaluated the effectiveness of SIG and BG in predicting the prognosis of patients with AOPP. Results The abnormal index of blood glucose (P=0. 001) indicated a higher risk of death than the normal index, SIG showed higher ORs for fatality than BG (P <0. 05). In the ROC curve, the area under the curve of the SIG, BG on the prognosis of fatality was 0. 856, 0. 817, respectively. Conclusion With early SIG and BG level increase, the risk of death will increase in acute organophosphorus pesticide poisoning, and SIG is a more effective marker than index of BG on the prognosis of death.

  15. 新烟碱类杀虫剂对家蚕的急性毒性评价与中毒症状观察%Acute Toxicity Evaluation of Neonicotinoid Insecticides to Bombyx mori and Observation of Toxic Symptoms

    Institute of Scientific and Technical Information of China (English)

    崔新倩; 张骞; 姜辉; 林荣华; 王开运

    2012-01-01

    为明确新烟碱类杀虫剂对非靶标生物家蚕的毒性以及对生态环境的安全性影响,采用浸叶法测定6种新烟碱类杀虫剂及其它3类对照杀虫剂对家蚕的急性毒性,并观察不同种类杀虫剂引起家蚕的急性中毒症状差异.6种新烟碱类杀虫剂中噻虫胺、吡虫啉、噻虫啉和烯啶虫胺对家蚕2龄幼虫96 h的LC50分别为0.065 1、0.174、0.258、0.445 mg/L,属剧毒级农药,噻虫嗪和啶虫脒对家蚕2龄幼虫96 h的LC50分别为1.31、2.73 mg/L,属高毒级农药,6种药剂均对家蚕存在极大的安全风险性.新烟碱类杀虫剂引起家蚕中毒的症状主要表现为拒食,身体扭曲呈“C”或“S”形,头部肿大等.其它3类杀虫剂中,抗生素类杀虫剂阿维菌素的毒性属剧毒级,并在测定药剂中的毒性最高,家蚕中毒症状主要表现为吐液、头部或尾部翘起、拒食等;有机磷类杀虫剂毒死蜱的毒性属高毒级,家蚕中毒症状与新烟碱类杀虫剂相似;吡咯类杀虫剂虫螨腈的毒性属中毒级.因新烟碱类杀虫剂对家蚕的毒性强,建议远离桑园使用,以避免对养蚕生产造成危害.%In order to identify the toxicity of neonicotinoid insecticides to non-target organism silkworm (Bombyx mori) and their impact on the security of ecological environment,we determined and compared the acute toxicity of 6 neonicotinoid insecticides and 3 other insecticides to silkworm with leaf dipping method.The differences in symptoms of acute toxicity caused by treatment with various kinds of insecticides were observed and recorded.The results indicated that,among the 6 neonicotinoid insecticides,LC50 of clothianidin,imidacloprid,thiacloprid and nitenpyram to the 2nd instar silkworm larvae at 96 h was 0.065 1,0.174,0.258 and 0.445 mg/L respectively,being pesticides of virulent toxicity grade.That of thiamethoxam and acetamiprid was 1.31 and 2.73 mg/L respectively,being pesticides of high toxicity grade.They all had

  16. CHANGES IN LIVER IN CASE OF INSECTICIDAL AND ALCOHOL POISONING: AN AUTOPSY STUDY

    Directory of Open Access Journals (Sweden)

    Subhasish

    2015-03-01

    Full Text Available Poison is a substance introduced in the body to produce ill - effect, disease or death. It may be of any origin like synthetic, mineral, animal or vegetable. Death due to poisoning is mostly prevalent in the developing countries, of the total burden of acute pesticide poisoning; the majority of deaths are from deliberate self - poisoning with organophosphorus pesticides, aluminium phosphide and paraquat. Exposure to pesticides is usually occupational, accidental or suicidal. In India very few research works hav e been undertaken on histopathological changes of liver in different poisoning. In this part of our country a sizable number of cases of poisoning due to insecticides & alcohol are reported. So this current study intends to find out different histopatholog ical changes of liver in insecticidal & alcohol poisoning with regards to time interval between poisoning and death. In our 1 year (November 2012 - October 2013 of study we got 143 victims who died due to insecticidal and alcohol poisoning, out of which 132 cases show significant histopathological changes in liver. In this study male subjects (60.83% outnumber female (39.17% victims and most common age group affected in this study is between 20 - 40 years. This study show 29.37% victims died due to organopho sphorus poisoning, 25.17% cases of organochlorine poisoning, 11.88% study subjects from carbamate poisoning, 18.88% cases died due to combined alcohol and insecticidal poisoning, and 14.68% victims died due to alcohol poisoning. On microscopically 25.87% o f cases show centrilobular necrosis(CN, sinusoidal dilatation(SD found in 22.37%, fatty changes(FC in 11.88%, both venous congestion(VC, combined sinusoidal dilatation and degenerative change in 1.39% of cases, each 2.09% of cases show degenerative cha nge(DC , centrilobular necrosis and venous congestion , and sinusoidal dilatation and venous congestion respectively, each 3.49% show combined centrilobular necrosis and sinusoidal

  17. Effects of organophosphate,carbamate and pyrethroid insecticides and their mixtures on neuromuscular junction transmission

    Institute of Scientific and Technical Information of China (English)

    HeFS; XiaoC

    2002-01-01

    To investigate the effects of organophosphorus (OP),carbamate (Carb),pyrehroid (Pyr) insecticides and their mixtures on neuromuscular junction transmission (NMJT),dimethoate(D) and phoxim(P),methomyl(M),and fenvalerate(F) were selected.Rats were intraperitoneally intoxicated by D,P,M,F,D+M,D+F,P+M,or P+F with the dosage of each LD50 respectively.The function of the NMJT was assessed with the mean consecutive differences (MCD) of the latencies of single fiber action potentials detected by stimulation single fiber electromyography(SSFEMG) at the stimulus frequency of 20 Hz.The SSFEMG was also applied to detect the function of NMJT in 40 patients with OPs and their mixtures poisoning in this study.The results showed that (1)the myasthenia occurred only in rats with OPs and their mixtures poisoning,but not in F,M intoxicated rats.The increase of MCD shown by SSFEMG and induced by OP and their mixtures indicating a post-synaptic block was well correlated with the occurrence of myasthenia both in rats and patients(P<0.001);(2)the increase of MCD in rats of OP poisoning was significant in comparison with the control and F,M intoxicated rats;but was not significantly different from those in rats intoxicated by OP mixtures;(3)the MCDs were significantly increased in IMS patients of both acute OP poisoning and OP mixtures poisoning,but showing no significant difference between the two groups of patients.It is concluded that OP is the only responsible agent for the dysfunction of neuromuscular transmission induced by single OP and OP mixture insecticides which could be sensitively detected by SSFEMG.

  18. 急性有机磷农药中毒84例的抢救及护理%The rescue and nursing of 84 cases of acute organophosphorus pesticide poisoning

    Institute of Scientific and Technical Information of China (English)

    袁晓春

    2015-01-01

    目的:迅速清除毒物,及时使用解毒剂和尽快达到阿托品化以对抗烟碱样症状、毒蕈碱样症状、中枢神经系统症状,减轻对重要器官的损害,提高抢救成功率,防止反跳与猝死的发生。方法:催吐、洗胃、清除毒物,尽早快速使用解毒剂,使其短期达到阿托品化,对症处置。结果:84例有机磷农药中毒患者经及时抢救,精心护理,80例痊愈出院,4例死于呼吸、循环衰竭。结论:有机磷农药中毒抢救的关键是早期及时应用解毒剂,短期达到阿托品化,迅速彻底清除毒物,密切观察病情,采取有效的护理措施,可大大提高抢救成功率。%Objective:In order to fight against nicotine symptoms,muscarinic symptoms,central nervous system symptoms,to alleviate the damage of the vital organs,improve the success rate of rescue,prevent the occurrence of rebound and sudden death by quickly remove poisons,timely use of antidotes and reach atropinization as soon as possible.Methods: The use of emetic,gastric lavage,clean up the poison,early rapid use antidote,make its short-term reach atropinization and symptomatic disposal.Results:84 cases of organophosphorus pesticide poisoning patients with timely rescue,careful nursing,80 cases were cured,4 cases died of respiratory and circulatory failure.Conclusion:The key to rescue organophosphorus pesticide poisoning is that the early and timely application of antidote,short-term reach atropinization,quickly and thoroughly remove poison,close observation of disease,take effective nursing measures,which can greatly improve the success rate of rescue.

  19. Insecticide resistance and activities of relative enzymes in different populations of the white backed planthopper

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ White backed planthopper (WBPH), Sogatella furcifera (Horvath), is one of the most devastating insect pests on rice in Asia. Its control mainly depended on the chemical pesticides. Surveys of insecticide susceptibility revealed that organophosphorus and carbamate resistance has emerged since early 1980s in China and Japan. WBPH has the long distance migration property, and Heinrichs(1994) considered that the migration might influence the resistance level of planthoppers. So we conducted the comparative studies on insecticide susceptibility and activities of resistance relative enzymes in four WBPH populations collected from Zhejiang, Yunnan, and Hainan provinces of China in 1997.

  20. Subchronic organophosphorus ester-induced delayed neurotoxicity in mallards

    Science.gov (United States)

    Hoffman, D.J.; Sileo, L.; Murray, H.C.

    1984-01-01

    Eighteen-week-old mallard hens received 0, 10, 30, 90, or 270 ppm technical grade EPN (phenylphosphonothioic acid O-ethyl-O-4-nitrophenyl ester) in the diet for 90 days. Ataxia was first observed in the 270-ppm group after 16 days, in the 90-ppm group after 20 days, in the 30-ppm group after 38 days; 10 ppm failed to produce ataxia. By the end of 90 days all 6 birds in the 270-ppm group exhibited ataxia or paralysis whereas 5 of 6 birds in the 90-ppm group and 2 of 6 birds in the 30-ppm group were visibly affected. Treatment with 30 ppm or more resulted in a significant reduction in body weight. Brain neurotoxic esterase activity was inhibited by averages of 16, 69, 73, and 74% in the 10-, 30-, 90-, and 270-ppm groups, respectively. Brain acetylcholinesterase, plasma cholinesterase, and plasma alkaline phosphatase were significantly inhibited as well. Distinct histopathological effects were seen in the 30-, 90-, and 270-ppm groups which included demyelination and degeneration of axons of the spinal cord. Additional ducks were exposed in a similar manner to 60-, 270-, or 540-ppm leptophos (phosphonothioic acid O-4-bromo-2,5-dichlorophenyl-O-methylphenyl ester) which resulted in similar behavioral, biochemical, and histopathological alterations. These findings indicate that adult mallards are probably somewhat less sensitive than chickens to subchronic dietary exposure to organophosphorus insecticides that induce delayed neurotoxicity.

  1. 活性炭和甘露醇联合应用对急性有机磷农药中毒的疗效%Effect of joint of activated charcoal and mannitol on the efficacy of treating acute organophosphorus pesticide poisoning

    Institute of Scientific and Technical Information of China (English)

    段新旺; 黄亮; 赖谋锋

    2010-01-01

    Objective To study the effect of oral administration of activated charcoal and mannitol on removing toxicant after acute organophosphorus pesticide poisoning (AOPP). Method A total of 41 patients with severe AOPP were randomly divided into experiment group (activated charcoal used as adsorbent and mannitol used as cathartics, n =21)and control group (without adsorbent and cathartics, n = 20). Patients of both groups received routine treatment for AOPP after admission to hospital. The differences in duration of atropinization, the length of hospitalization and the success rate of treatment were compared between two groups. Results There were significant differences in duration of atropinization, the success rate of treatment and hospitalization time between the two groups. Conclusions The combination of activated charcoal and mannitol is more effective than the conventional gastric lavage on removal of organophosphorus pesticides from G-I tract, shorting the duration of atropinization time and hospital stays, and enhancing the success rate of rescue as well as improving the outcome of patients after organophosphorus pesticide poisoning.%目的 探讨口服活性炭和甘露醇对急性有机磷农药中毒(AOPP)的毒物清除作用.方法 2004年1月至2009年12月南昌大学第一附属医院收治的41例重症AOPP患者随机分为试验组(活性炭吸附毒物和甘露醇导泻治疗组,n=21)和对照组(未用活性炭吸附毒物和甘露醇导泻治疗组,n=20).两组患者均进行AOPP急救常规治疗,观察两组患者阿托品化时间、抢救成功率和住院时间的差异.结果 试验组阿托品化时间、抢救成功率和住院时间与对照组比较差异[(3.60±1.6)h vs.(17.5±13.4)h;(4.1±1.45)d vs.(8.00±2.13)d;100% vs.(70.0±4.7)]均有统计学意义(P<0.01).结论 活性炭和甘露醇联合应用较传统洗胃法更能有效清除进入体内的有机磷农药,且能缩短患者阿托品化时间和住院时间,进一步提

  2. Paraoxonase 1 (PON1) Status and Risk of Insecticide Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Furlong, Clement E.; Cole, Toby B.; Walter, Betsy J.; Shih, Diana M.; Tward, Aaron; Lusis, Aldons J.; Timchalk, Chuck; Richter, Rebecca J.; Costa, Lucio G.

    2005-06-23

    Paraoxonase 1 (PON1) is an HDL associated enzyme that catalyzes a number of different reactions including the hydrolysis of the toxic oxon metabolites of the insecticides diazinon and chlorpyrifos. PON1 has also been implicated in the detoxication of oxidized lipids and the metabolism of a number of drugs, activating some, while inactivating others. There are two common PON1 coding region polymorphisms (L55M and Q192R). The latter determines the catalytic efficiency of hydrolysis of a number of substrates including chlorpyrifos oxon, but not diazoxon. Evidence for the physiological importance of PON1 in modulating exposures to these two insecticides comes from several different studies. Early studies noted that species with high levels of PON1 were much more resistant to certain organophosphorus (OP) insecticides than were species with low levels. Another early study by Main demonstrated that injected rabbit paraoxonase protected rats from paraoxon toxicity. Our research group began the development of a mouse model system for examining the importance of PON1 in the detoxication of OP insecticides.

  3. 四种镇静药物对急性有机磷中毒机械通气患者的疗效和安全性对比研究%The efficacy and safety of four kinds of sedative drugs in patients with acute organophosphorus poisoning undergoing mechanical ventilation

    Institute of Scientific and Technical Information of China (English)

    于中锴; 孙宝泉; 姜学青; 赵波; 刘乃政; 杨静杰; 陈士超

    2015-01-01

    目的:比较常用四种镇静药物对急性有机磷中毒机械通气患者的疗效和安全性,为临床合理用药提供循证依据。方法选取急性有机磷中毒机械通气患者84例随机平均分成4组,分别按药品说明书和相关专业指南给予静脉泵入地西泮、咪达唑仑、丙泊酚、右美托咪定镇静。按Ramsay分级法评估镇静效果;密切监测生命体征及各项生化指标。结果镇静后4组患者的心率、呼吸频率及平均动脉压都出现降低的情况,且与镇静前相比有统计学差异(P<0.05),但无论是镇静前还是镇静后,4组患者各项指标的组间比较均无统计学差异(P>0.05);右美托咪定组患者的不良反应发生率最低(P<0.05)。结论四种药物均能有效达到急性有机磷中毒机械通气的镇静要求;右美托咪定的安全性明显优于其他药物,但各药发生的不同程度的不良反应,经停药并积极处理后均能很快恢复。%Objective To compare the efficacy and safety of four kinds of sedative drugs in patients with acute organophosphorus poisoning undergoing mechanical ventilation and provide evidence for the rational use of drugs.Method Selected patients (84 cases) were randomly divided into four groups and given intravenous infusion of diazepam, midazolam, propofol and dexmedetomidine. Sedative effect was evaluated according to Ramsay's classification evaluation and vital signs and biochemical indexes were monitored and recorded at the same time. Result Heart rate(HR), respiratory frequency(RR) and mean arterial pressure (MAP) except for pulse oxygen saturation in four groups after treatment significantly decrease, compared with the data before treatment (P0.05, respectively). The incidence of the adverse effects of patients treated by dexmedetomidine was the lowest (P<0.05,respectively).Conclusion Four drugs are effective in maintaining sedation of patients with acute organophosphorus

  4. Identification and isolation of bacteria containing OPH enzyme for biodegradation of organophosphorus pesticide diazinon from contaminated agricultural soil

    Directory of Open Access Journals (Sweden)

    Sara Mobarakpoor

    2015-04-01

    Full Text Available Background: Organophosphorus insecticide diazinon has been widely used in agriculture and has the ability to transfer and accumulate in soil, water and animal tissues, and to induce toxicity in plants, animals and humans. In humans, diazinon inhibits nerve transmission by inactivating acetylcholinesterase enzyme. The present study was carried out to identify bacteria containing OPH enzyme for biodegradation of diazinon from contaminated agricultural soil. Methods: In this study, 8 contaminated agricultural soil samples that were exposed to pesticides, especially diazinon in the last two decades, were collected from the farms of Hamedan province. After preparing the media, for isolation of several bacterial strains containing OPH enzyme that are capable of biodegrading organophosphorus pesticides by diazinon enzymatic hydrolysis, bacterial genomic DNA extraction, plasmid product sequencing, phylogenetic sequence processing and phylogenetic tree drawing were carried out. Results: Eight bacterial strains, capable of secreting OPH enzyme, were isolated from soil samples, one of which named BS-1 with 86% similarity to Bacillus safensis displayed the highest organophosphate-hydrolyzing capability and can be used as a source of carbon and phosphorus. Conclusion: It can be concluded that the isolated bacterial strain identified in this study with OPH enzyme secretion has the potential for biodegradation of organophosphorus pesticides, especially diazinon in invitro conditions. Also, further studies such as the environmental stability and interaction, production strategies, safety, cost-benefit, environmental destructive parameters, and, toxicological, genetic and biochemical aspects are recommended prior to the application of bacterial strains in the field-scale bioremediation.

  5. A retrospective study of paradigm and outcome of acute poisoning cases in a tertiary care teaching hospital in Southern India

    Directory of Open Access Journals (Sweden)

    Arulmurugan C.

    2015-10-01

    Results: Incidence was high among males (60.36% compared to females (39.64%. Most of the cases of acute poisoning were in the age group 10 to 30 years (60.95% followed by 30 to 50 years age group (30.77%. A majority of poisoning cases (27.2% were due to organophosphorus (OPC insecticide. Total mortality was found to be 5.32%. Mortality rate due to Paraquat, Abrus Pretorius seeds was significantly high compared with OPC because there is no specific antidote. Time lapse had a very significant role in the mortality in cases of poisoning. Conclusions: Poisoning is common with young males. The mortality is high, in cases of self-poisoning with parquet and abrus seeds. Despite the highest consumption rate, no mortality was observed with organophosphorus because of early medical intervention and specific antidote. Early medical care in a tertiary care hospital will help to reduce significant mortality in India. [Int J Res Med Sci 2015; 3(10.000: 2654-2657

  6. Optical biosensor for simultaneous detection of captan and organophosphorus compounds.

    Science.gov (United States)

    Choi, Jeong-Woo; Kim, Young-Kee; Oh, Byung-Keun; Song, Sun-Young; Lee, Won Hong

    2003-05-01

    The optical biosensor consisting of GST and acetylcholinesterase (AChE)-immobilized gel film was developed to detect captan and organophosphorus compounds simultaneously in contaminated water. The sensing scheme was based on the measurement of decrease of products formation (s-(2,4-dinitrobenzene) glutathione and alpha-naphthol by GST and AChE, respectively) due to the inhibition by captan and organophosphorus compounds. The absorbance of s-(2,4-dinitrobenzene) glutathione and alpha-naphthol was detected at 400 and 500 nm, respectively, by a proposed optical biosensor system. It was observed that AChE was inhibited by both captan and organophosphorus compounds, and GST was inhibited only by captan. The simultaneous detection and quantification of captan and organophosphorus compounds could be successfully achieved by the proposed sensor system. The proposed biosensor could successfully detect the captan and organophosphorus compounds concentration from 0 to 2 ppm.

  7. Insecticide Compendium. MP-29.

    Science.gov (United States)

    Spackman, Everett W.; And Others

    This document presents information on most of the known insecticides and their general usage, toxicity, formulation, compound type, manufacturers, and the chemical, trade and common names applied to each compound. (CS)

  8. Insecticides and Biological Control

    Science.gov (United States)

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  9. More about Insecticides

    Directory of Open Access Journals (Sweden)

    E.K. Hartwig

    1980-09-01

    Full Text Available An insecticide is a chemical used to kill insects. Insect control can also include other materials such as repellents, oils, antifeedants and attractants. Ideally, an insecticide would effectively control any target insect exposed to it and would be harmless to man and his domestic animals. It would also be readily available in necessary quantitie s , s table chemically, noninflammable, easily prepared and applied, noncorrosive, non-staining, and would have no undesirable odour.

  10. Proteases as Insecticidal Agents

    OpenAIRE

    Robert L. Harrison; Bonning, Bryony C.

    2010-01-01

    Proteases from a variety of sources (viruses, bacteria, fungi, plants, and insects) have toxicity towards insects. Some of these insecticidal proteases evolved as venom components, herbivore resistance factors, or microbial pathogenicity factors, while other proteases play roles in insect development or digestion, but exert an insecticidal effect when over-expressed from genetically engineered plants or microbial pathogens. Many of these proteases are cysteine proteases, although insect-toxic...

  11. A role for solvents in the toxicity of agricultural organophosphorus pesticides.

    Science.gov (United States)

    Eddleston, Michael; Street, Jonathan M; Self, Ian; Thompson, Adrian; King, Tim; Williams, Nicola; Naredo, Gregorio; Dissanayake, Kosala; Yu, Ly-Mee; Worek, Franz; John, Harald; Smith, Sionagh; Thiermann, Horst; Harris, John B; Eddie Clutton, R

    2012-04-11

    Organophosphorus (OP) insecticide self-poisoning is responsible for about one-quarter of global suicides. Treatment focuses on the fact that OP compounds inhibit acetylcholinesterase (AChE); however, AChE-reactivating drugs do not benefit poisoned humans. We therefore studied the role of solvent coformulants in OP toxicity in a novel minipig model of agricultural OP poisoning. Gottingen minipigs were orally poisoned with clinically relevant doses of agricultural emulsifiable concentrate (EC) dimethoate, dimethoate active ingredient (AI) alone, or solvents. Cardiorespiratory physiology and neuromuscular (NMJ) function, blood AChE activity, and arterial lactate concentration were monitored for 12h to assess poisoning severity. Poisoning with agricultural dimethoate EC40, but not saline, caused respiratory arrest within 30 min, severe distributive shock and NMJ dysfunction, that was similar to human poisoning. Mean arterial lactate rose to 15.6 [SD 2.8] mM in poisoned pigs compared to 1.4 [0.4] in controls. Moderate toxicity resulted from poisoning with dimethoate AI alone, or the major solvent cyclohexanone. Combining dimethoate with cyclohexanone reproduced severe poisoning characteristic of agricultural dimethoate EC poisoning. A formulation without cyclohexanone showed less mammalian toxicity. These results indicate that solvents play a crucial role in dimethoate toxicity. Regulatory assessment of pesticide toxicity should include solvents as well as the AIs which currently dominate the assessment. Reformulation of OP insecticides to ensure that the agricultural product has lower mammalian toxicity could result in fewer deaths after suicidal ingestion and rapidly reduce global suicide rates.

  12. Mitochondrial dysfunction and organophosphorus compounds

    Energy Technology Data Exchange (ETDEWEB)

    Karami-Mohajeri, Somayyeh [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Kerman University of Medical Sciences, Kerman (Iran, Islamic Republic of); Abdollahi, Mohammad, E-mail: Mohammad.Abdollahi@UToronto.Ca [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2013-07-01

    Organophosphorous (OPs) pesticides are the most widely used pesticides in the agriculture and home. However, many acute or chronic poisoning reports about OPs have been published in the recent years. Mitochondria as a site of cellular oxygen consumption and energy production can be a target for OPs poisoning as a non-cholinergic mechanism of toxicity of OPs. In the present review, we have reviewed and criticized all the evidences about the mitochondrial dysfunctions as a mechanism of toxicity of OPs. For this purpose, all biochemical, molecular, and morphological data were retrieved from various studies. Some toxicities of OPs are arisen from dysfunction of mitochondrial oxidative phosphorylation through alteration of complexes I, II, III, IV and V activities and disruption of mitochondrial membrane. Reductions of adenosine triphosphate (ATP) synthesis or induction of its hydrolysis can impair the cellular energy. The OPs disrupt cellular and mitochondrial antioxidant defense, reactive oxygen species generation, and calcium uptake and promote oxidative and genotoxic damage triggering cell death via cytochrome C released from mitochondria and consequent activation of caspases. The mitochondrial dysfunction induced by OPs can be restored by use of antioxidants such as vitamin E and C, alpha-tocopherol, electron donors, and through increasing the cytosolic ATP level. However, to elucidate many aspect of mitochondrial toxicity of Ops, further studies should be performed. - Highlights: • As a non-cholinergic mechanism of toxicity, mitochondria is a target for OPs. • OPs affect action of complexes I, II, III, IV and V in the mitochondria. • OPs reduce mitochondrial ATP. • OPs promote oxidative and genotoxic damage via release of cytochrome C from mitochondria. • OP-induced mitochondrial dysfunction can be restored by increasing the cytosolic ATP.

  13. Compound specific isotope analysis of organophosphorus pesticides.

    Science.gov (United States)

    Wu, Langping; Yao, Jun; Trebse, Polonca; Zhang, Ning; Richnow, Hans H

    2014-09-01

    Compound-specific isotope analysis (CSIA) has been established as a tool to study the environmental fate of a wide range of contaminants. In this study, CSIA was developed to analyse the stable carbon isotope signatures of the widely used organophosphorus pesticides: dichlorvos, omethoate and dimethoate. The linearity of the GC-C-IRMS system was tested for target pesticides and led to an acceptable isotope composition within the uncertainty of the instrument. In order to assess the accuracy of the developed method, the effect of the evaporation procedure on measured carbon isotope composition (δ(13)C) values was studied and showed that concentration by evaporation of solvents had no significant isotope effect. The CSIA was then applied to investigate isotope fractionation of the hydrolysis and photolysis of selected pesticides. The carbon isotope fractionation of tested pesticides was quantified by the Rayleigh model, which revealed a bulk enrichment factor (ε) of -0.2±0.1‰ for hydrolysis of dichlorvos, -1.0±0.1‰ and -3.7±1.1‰ for hydrolysis and photolysis of dimethoate respectively. This study is a first step towards the application of CSIA to trace the transport and degradation of organophosphorus pesticides in the environment.

  14. Chlorination of organophosphorus pesticides in natural waters.

    Science.gov (United States)

    Acero, Juan L; Benítez, F Javier; Real, Francisco J; González, Manuel

    2008-05-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 degrees C and pH 7 were determined to be 110.9, 0.004 and 191.6 M(-1) s(-1) for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L(-1) was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety.

  15. Resistance to Insecticides in Insects

    OpenAIRE

    2005-01-01

    In recent years, the frequent usage of insecticides in struggle aganist insects, has caused development of resistance to those chemicals in insects. The increase in dosage of insecticide used due to development of resistance in insects, causes important problems in terms of environment and human health. This study includes topics such as insecticides which are used frequently in insect struggle, insecticide resistant types, genetic changes posing resistance, enzymes of resistance and resistan...

  16. Isolatable organophosphorus(III)-tellurium heterocycles.

    Science.gov (United States)

    Nordheider, Andreas; Chivers, Tristram; Schön, Oliver; Karaghiosoff, Konstantin; Athukorala Arachchige, Kasun S; Slawin, Alexandra M Z; Woollins, J Derek

    2014-01-13

    A new structural arrangement Te3 (RP(III) )3 and the first crystal structures of organophosphorus(III)-tellurium heterocycles are presented. The heterocycles can be stabilized and structurally characterized by the appropriate choice of substituents in Tem (P(III) R)n (m=1: n=2, R=OMes* (Mes*=supermesityl or 2,4,6-tri-tert-butylphenyl); n=3, R=adamantyl (Ad); n=4, R=ferrocene (Fc); m=n=3: R=trityl (Trt), Mesor by the installation of a P(V) 2 N2 anchor in RP(III) [TeP(V) (tBuN)(μ-NtBu)]2 (R=Ad, tBu).

  17. Insecticide applications to soil contribute to the development of Burkholderia mediating insecticide resistance in stinkbugs.

    Science.gov (United States)

    Tago, Kanako; Kikuchi, Yoshitomo; Nakaoka, Sinji; Katsuyama, Chie; Hayatsu, Masahito

    2015-07-01

    Some soil Burkholderia strains are capable of degrading the organophosphorus insecticide, fenitrothion, and establish symbiosis with stinkbugs, making the host insects fenitrothion-resistant. However, the ecology of the symbiotic degrading Burkholderia adapting to fenitrothion in the free-living environment is unknown. We hypothesized that fenitrothion applications affect the dynamics of fenitrothion-degrading Burkholderia, thereby controlling the transmission of symbiotic degrading Burkholderia from the soil to stinkbugs. We investigated changes in the density and diversity of culturable Burkholderia (i.e. symbiotic and nonsymbiotic fenitrothion degraders and nondegraders) in fenitrothion-treated soil using microcosms. During the incubation with five applications of pesticide, the density of the degraders increased from less than the detection limit to around 10(6)/g of soil. The number of dominant species among the degraders declined with the increasing density of degraders; eventually, one species predominated. This process can be explained according to the competitive exclusion principle using V(max) and K(m) values for fenitrothion metabolism by the degraders. We performed a phylogenetic analysis of representative strains isolated from the microcosms and evaluated their ability to establish symbiosis with the stinkbug Riptortus pedestris. The strains that established symbiosis with R. pedestris were assigned to a cluster including symbionts commonly isolated from stinkbugs. The strains outside the cluster could not necessarily associate with the host. The degraders in the cluster predominated during the initial phase of degrader dynamics in the soil. Therefore, only a few applications of fenitrothion could allow symbiotic degraders to associate with their hosts and may cause the emergence of symbiont-mediated insecticide resistance.

  18. Acute Toxicity of Seven Pyrethroid Insecticides to Brine Shrimp Artemia%7种拟除虫菊酯农药对卤虫的急性毒性研究

    Institute of Scientific and Technical Information of China (English)

    刘永; 汪小月; 邱立红; 李学锋; 王成菊

    2011-01-01

    To study the acute toxic effects of seven pyrethroid insecticides on the Great Salt Lake (GSL) Artemia, Ar temia nauplii hatched out within 18-24 h were picked out, and then continued to be cultured for another 24 h under the same condition to obtain the 2nd-3rd instar nauplii. The obtained GSL Artemia were exposed to different concentrations of pyrethroid solutions for 24 h, and the lethal effects were recorded. The results of Probit analysis showed that lethal effects of the seven studied pyrethroids on GSL Artemia were very different from each other. The 24 h median lethal concentrations (24 h-LC50) of permethrin, chlorenthrin, imiprothrin, tetramethrin, bifenthrin, lambadacyhalothrin, delta methrin to brine shrimp were 4.68, 14.82, 18.12, 38.21, > 100, > 100, > 100 mg·L-1, respectively. Therefore, in the Artemia-living saline environment, the pyrethroid insecticides with relatively lower toxicity including bifenthrin, lambada cyhalothrin and dehamethrin should be given prior consideration rather than the highly toxic permethrin.%为了研究7种拟除虫菊酯农药对美国大盐湖卤虫(GSL Artemia)的急性毒性效应,挑选18 ~24 h内孵出的卤虫,继续培养24h后得到Ⅱ~Ⅲ龄卤虫无节幼体,将其暴露于所设浓度梯度的拟除虫菊酯溶液中进行24h急性毒性实验,记录卤虫无节幼体在各浓度溶液中的死亡情况,并将所得数据进行Probit分析.结果表明,卤虫对不同拟除虫菊酯的敏感性相差较大.氯菊酯、氯烯炔菊酯、炔咪菊酯、胺菊酯、联苯菊酯、高效氯氟氰菊酯和溴氰菊酯对卤虫的24 h半致死浓度(24 h-LC50)分别为4.68、14.82、18.12、38.21、>100、>100和>100 mg·L-1.因此,在含有卤虫的盐水环境中,应尽量避免使用毒性较高的氯菊酯,而选择使用联苯菊酯、高效氯氟氰菊酯和溴氰菊酯等毒性较低的农药.

  19. 庫存血液膽碱酯酶水平變化及其在重症有機磷中毒搶救中應用選擇%Alteration of Banked Blood Cholinesterase Level and Its Significance in Emergency Treatment of Acute Organophosphorus Pesticide Poisoning

    Institute of Scientific and Technical Information of China (English)

    鍾沛霖; 王勤鷹; 盛慧球

    2002-01-01

    目的觀察庫血保存天數與血漿膽碱酯酶(CHE)水平變化關係;探討重症有機磷農藥中毒(AOPP)搶救中合理選擇血源.方法輸血前隨機留取保留不同天數的庫血測定血漿CHE值;血液中心採血當日留取正常人血漿、即日測定CHE值作對照組.CHE測定用BM公司膽碱酯酶試劑盒,Roch公司的Cobas-FaraⅡ自動分析儀測定.結果庫血保存天數為第一天的血漿CHE值與正常對照組比較無顯著差異(p>o.05),其他各組均顯著低於對照組(P>0.05).各組與正常對照組相比較其下降百分比約19%-83%.保存天數與CHE值呈負相關(r=-0.7929,P<0.01).曲線回歸Y=-1 823.3Ln(X)+6229.4.結論隨採血後庫血保存天數的增加,血漿CHE值逐漸下降.在重度AOPP搶救中,以使用保留天數為一天以內新鮮血液最為適宜,以免浪費血源,貽( )搶救時機.本報告為強調輸入新鮮血液,保證高活性膽碱酯酶輸入提供實驗依據,並可供臨床參考.%Objective To observe the relationship between the preservation days of banked blood and the alteration level of plasma cholinesterase(CHE) with the aim of making proper selection of banked blood in emergency treatment of acute organophosphorus pesticide poisoning (AOPP). Methods We selected at random the banked blood that has been stored for different length of time before blood transfusion so as to determine the plasma cholinesterase value. The normal plasma cholinesterase value was determined on blood samples in the Blood Center which served as a control group. The cholinesterase value was determined with a kit of the BM Company and the Cobas-Fara Ⅱ automatic analysis of the Roch Company. Results It was found that there was no significant difference of plasma cholinesterase value between the one-day banked blood and the normal control group (P>0.05), but the plasma cholinesterase values of the other experiment groups were all significantly lower than that of the control group(P<0.05). As

  20. The protection effect of benthiactzine on gut-barrier in acute organophosphorus pesticide poisoning%宾赛克嗪对有机磷农药中毒时肠黏膜屏障功能破坏的保护作用

    Institute of Scientific and Technical Information of China (English)

    王喆; 潘志远; 龙超良; 邱泽武; 汪海

    2009-01-01

    Objective To investigate the change of gut-barrier function of mice in acute organophosphorus poisoning and the protection effect of benthiactzine. Method A total of 65 Kunming mice, female and male both half, were randomly assigned to five groups: normal group, DDVP poisoning(model) group, and benthiactzine 2, sured by spectrophotometric assay at 3 hours after DDVP poisoning. The variance analysis was used to deal the quantitative data. Results The DAO activity in model group significantly increased compared with normal group (P < 0.01). Whereas, the DAO activity in all pretreatment groups were significantly decreased compared with model group(all P<0.01).The effects of benthisetzine 6 mg·kg~(-1) pretrentment group was the best of all.The concentration of D-lactate in model group was significantly increased compared with normal group (P < 0.01). However, the concentration of D-lactate in pretreatment groups was significantly decreased compared with model group(all P < 0.01). The concentration of D-lactate could be decreased dose-dependently by the administration of benthiactzine. Conclusions The diamine oxidase activity and concentration of D-lactate were significantly in-creased in the DDVP poisoning mice, which means the gnt-barrier function was severely damaged. And the admin-istration of benthiactzine could alleviate the injury to the gut-barrier function.%目的 研究有机磷农药敌敌畏中毒后小鼠肠黏膜屏障功能的变化及新型抗毒剂宾赛克嗪的保护作用.方法昆明小鼠65只,雌雄各半,随机分为正常对照组、敌敌畏染毒模型组、宾赛克嗪2,6,18mg/ks预防治疗组;各预防治疗组腹腔注射预防给予相应约物,10min后灌胃给予敌敌畏55mg/ks,于染毒后3 h取血,使用紫外分光光度计检测血浆二胺氧化酶(DAO)活性及D-乳酸质量浓度,采用单因素方差分析定量数据.结果 与正常对照组比较,模型组血浆DAO活性明显升高(P<0.01);与模型组比较,各预防治

  1. Sex differences and effects of estrogenic compounds on the expression of inflammatory molecules by astrocytes exposed to the insecticide dimethoate.

    Science.gov (United States)

    Astiz, Mariana; Acaz-Fonseca, Estefania; Garcia-Segura, Luis M

    2014-04-01

    A low dose of the organophosphorus insecticide dimethoate (DMT) produces oxidation of lipids and proteins and impairs mitochondrial function in the brain of male rats, together with a reduction of gonadal hormones in plasma. Here, we have assessed whether DMT affected the expression of inflammatory molecules, the production of reactive oxygen species (ROS), and the expression of steroidogenic proteins and estrogen receptors in cortical astrocyte-enriched cultures obtained separately from male and female CD1 mice pups. Furthermore, we have analyzed whether estradiol may counteract the effects of DMT. A dose of DMT (2 μg/mL) did not affect cell viability, increased interleukin (IL) 6, IL1β, tumor necrosis factor (TNF)α, interferon-γ-inducible protein 10 (IP10), ERβ, steroidogenic acute regulatory protein, and aromatase mRNA levels and ERα protein levels in male but not in female cultures. Estradiol decreased the mRNA levels of IL6, IP10, TNFα, and IL1β in male but not in female cultures treated with DMT. The effect of estradiol was prevented by the ER antagonist ICI 182,780, fully imitated by an ERβ agonist and partially imitated by an ERα agonist. Furthermore, DMT increased the production of ROS in male astrocytes while estradiol reduced ROS production to control levels. These findings indicate that a sublethal dose of DMT alters astrocyte function. The selective action of estradiol on male astrocytes and the sexually dimorphic action of DMT suggest that the pesticide may have different neurological outcomes in males and females.

  2. Neurotoxicological effects and the mode of action of pyrethroid insecticides

    NARCIS (Netherlands)

    Vijverberg, H.P.M.; Bercken, Joep van den

    1990-01-01

    Neuroexcitatory symptoms of acute poisoning of vertebrates by pyrethroids are related to the ability of these insecticides to modify electrical activity in various parts of the nervous system. Repetitive nerve activity, particularly in the sensory nervous system, membrane depolarization, and enhance

  3. Recent approaches to improving selectivity and sensitivity of enzyme-based biosensors for organophosphorus pesticides: A review.

    Science.gov (United States)

    Songa, Everlyne A; Okonkwo, Jonathan O

    2016-08-01

    Pesticide determination has attracted great attention due to the fact that they exhibit high acute toxicity and can cause long-term damage to the environment and human lives even at trace levels. Although classical analytical methods (including gas chromatography, high performance liquid chromatography, capillary electrophoresis and mass spectrometry) have been effectively used for analysis of pesticides in contaminated samples, they present certain limitations such as time-consuming sample preparation, complexity, and the requirement of expensive instrumentation and highly skilled personnel. For these reasons, there is an expanding need for analytical methods able to provide simple, rapid, sensitive, selective, low cost and reliable detection of pesticides at trace levels. Over the past decades, acetylcholinesterase (AChE) biosensors have emerged as simple, rapid and ultra-sensitive tools for toxicity detection of pesticides in the environment and food. These biosensors have the potential to complement or replace the classical analytical methods by simplifying or eliminating sample preparation and making field-testing easier and faster with significant decrease in cost per analysis. With the recent engineering of more sensitive AChE enzymes, the development of more reliable immobilization matrices and the progress in the area of microelectronics, AChE biosensors could become competitive for multi-analyte screening and soon be used for the development of portable instrumentation for rapid toxicity testing of samples. The enzymes organophosphorus hydrolase (OPH) and organophosphorus acid anhydrolase (OPAA) have also shown considerable potential in OP biosensor applications and they have been used for direct detection of OPs. This review presents the recent advances in the fabrication of enzyme biosensors for organophosphorus pesticides (OPs) and their possible applications for toxicity monitoring of organophosphorus pesticide residues in real samples. The focus will

  4. Exposures of aquatic organisms to the organophosphorus insecticide, chlorpyrifos resulting from use in the United States.

    Science.gov (United States)

    Williams, W Martin; Giddings, Jeffrey M; Purdy, John; Solomon, Keith R; Giesy, John P

    2014-01-01

    Concentrations of CPY in surface waters are an integral determinant of risk to aquatic organisms. CPY has been measured in surface waters of the U.S. in several environmental monitoring programs and these data were evaluated to characterize concentrations, in relation to major areas of use and changes to the label since 2001, particularly the removal of domestic uses. Frequencies of detection and 95th centile concentrations of CPY decreased more than fivefold between 1992 and 2010. Detections in 1992-2001 ranged from 10.2 to 53%, while 2002-2010 detections ranged from 7 to 11%. The 95th centile concentrations ranged from 0.007 to 0.056 j.lg L -I in 1992-2001 and 0.006-0.008 j.lg L -I in 2002-2010.The greatest frequency of detections occurred in samples from undeveloped and agricultural land-use classes. Samples from urban and mixed land-use classes had the smallest frequency of detections and 95th centile concentrations, consistent with the cessation of most homeowner uses in 2001. The active metabolite of CPY, CPYO, was not detected frequently or in large concentrations. In 10,375 analyses from several sampling programs conducted between 1999 and 2012, only 25 detections (0.24% of samples) of CPYO were reported and estimated concentrations were less than the LOQ.Although the monitoring data on CPY provide relevant insight in quantifying the range of concentrations in surface waters, few monitoring programs have sampled at a frequency sufficient to quantify the time-series pattern of exposure. Therefore,numerical simulations were used to characterize concentrations of CPY in water and sediment for three representative high exposure environments in the U.S. Thefate of CPY in the environment is dependent on a number of dissipation and degradation processes. In terms of surface waters, fate in soils is a major driver of the potential for runoff into surface waters and results from a number of dissipation studies in the laboratory were characterized. Aerobic degradation of CPY exhibits hi-phasic behavior in some soils; initial rates of degradation are greater than overal rates by factors of up to threefold. Along with fate in water, these data were considered in selecting parameters for the modeling concentrations in surface waters. An assessment of vulnerability to runoff was conducted to characterize the potential for CPY to be transported beyond a treated field in runoff water and eroded sediment across the conterminous U.S. A sensitivity analysis was performed on use practices of CPY to determine conditions that resulted in the highest potential runoff of CPY to aquatic systems to narrow the application practices and geographical areas of the country for selecting watersheds for detailed modeling. The selected focus-watersheds were Dry Creek in Georgia (production of pecans), Cedar Creekin Michigan (cherries), and Orestimba Creek in California (intensive agricultural uses). These watersheds provided realistic but reasonable worst-case predictions of concentrations of CPY in water and sediment.Estimated concentrations of CPY in water for the three watersheds were in general agreement with ambient monitoring data from 2002 to 20 I 0 in the datasets from US Geological Survey (USGS), California Department of Pesticide Regulation(CDPR), and Washington State Department of Ecology (WDOE). Maximum daily concentrations predicted for the watershed in California, Georgia, and Michigan were 3.2, 0.04 I, and 0.073 Jlg L -I, respectively, with the 28-d aerobic soil metabolism half-life and 4.5, 0.042, and 0. I 22 Jlg L - 1, respectively, with the 96-d soil halflife.These estimated values compared favorably with maximum concentrations measured in surface water, which ranged from 0.33 to 3.96 Jlg L -1• For sediments,the maximum daily concentrations predicted for the watersheds in California,Georgia, and Michigan were I 1.2, 0.077, and 0.058 Jlg kg-1, respectively, with the 28-d half-life and 22.8, 0.080, and 0.087 Jlg kg-1, respectively, with the 96-d soil half-life. CYP was detected in 12 samples (I 0%) out of 123 sample analyses that existed in the USGS, CDPR, and WDOE databases. The concentrations reported in these detections were from <2.0, up to 19 Jlg kg- 1, with the exception of one value reported at 58.6 Jlg kg- 1• Again, the modeled values compared favorably with these measured values. Duration and recovery intervals between toxicity threshold concentrations of 0.1 and 1.0 Jlg L - 1 were also computed. Based on modeling with the half-life of 28 d, no exceedance events were identified in the focus watersheds in Georgia or Michigan. Using the half-life of 96 d, only three events of 1-d duration only were identified in the Michigan focus-watershed. Frequency of exceedancc was greater in the California focus watershed, though the median duration was only I -d.

  5. Effects of the organophosphorus pesticide Folisuper 600 (methyl parathion on the heart function of bullfrog tadpoles, Lithobates catesbeianus (Shaw, 1802

    Directory of Open Access Journals (Sweden)

    M. J. Costa

    Full Text Available Abstract The aim of this work was to evaluate whether the heart function of bullfrog tadpoles (25 Gosner stage is affected by their acute exposure (48 h to a sub-lethal concentration (10 µg.L–1 of the active principle of the organophosphorus pesticide Folisuper 600R (methyl parathion - MP. Our results demonstrated that MP causes not only a reduction in tadpoles’ cardiac ventricular mass, resulting in a marked reduction in their cardiac twitch force, but also impairs their swimming performance, irrespective of increasing their heart rate. Together, these findings indicate that low and realistic concentration of MP have a negative impact on tadpoles’ performance, jeopardizing their survival.

  6. Pattern and outcome of acute poisoning cases in a tertiary care hospital in Karnataka, India

    Directory of Open Access Journals (Sweden)

    Ramesha K

    2009-01-01

    Full Text Available Background and Objective: Acute poisoning is a medical emergency. It is important to know the nature, severity and outcome of acute poisoning cases in order to take up appropriate planning, prevention and management techniques. This study aimed to assess the pattern and outcome of acute poisoning cases in a tertiary care hospital in Karnataka. Materials and Methods: This is a retrospective hospital record-based study conducted in a tertiary care hospital attached to a medical institution in Karnataka. The study included 136 cases and data regarding age, sex, time elapsed after intake; circumstances of poisoning, name of the poisonous substance, chemical type, duration of hospitalization, severity and outcome were collected in the prestructured proforma. Results: Incidence was more common among males (75.4% compared to females (24.3. Most cases of acute poisoning presented among 20- to 29-year age group (31.2% followed by 12- to 19-year age group (30.2%. A majority of poisoning cases (36.0% were due to organophosphorus compound (OPC. Total mortality was found to be 15.4%. Mortality rate due to corrosives was significantly high compared with OPC poisoning (χ2 = 4.12, P = 0.04. Of the 56 patients of OPC and carbamate poisoning, 13 patients (23.2% had respiratory arrest and required respiratory support. Time lapse had a significant role on the mortality in cases of acute poisoning (χ2 = 10.9, P = 0.01. Conclusion: Poisoning is more common in young males. The overall mortality is substantially high, mainly contributed by self-poisoning with insecticides and corrosives. Early care in a tertiary care center may help to reduce mortality in India.

  7. Relative toxicity and residual activity of insecticides used in blueberry pest management: mortality of natural enemies.

    Science.gov (United States)

    Roubos, Craig R; Rodriguez-Saona, Cesar; Holdcraft, Robert; Mason, Keith S; Isaacs, Rufus

    2014-02-01

    A series of bioassays were conducted to determine the relative toxicities and residual activities of insecticides labeled for use in blueberry (Vaccinium corymbosum L.) on natural enemies, to identify products with low toxicity or short duration effects on biological control agents. In total, 14 insecticides were evaluated using treated petri dishes and four commercially available natural enemies (Aphidius colemani Viereck, Orius insidiosus [Say], Chrysoperla rufilabris [Burmeister], and Hippodamia convergens [Guérin-Menéville]). Dishes were aged under greenhouse conditions for 0, 3, 7, or 14 d before introducing insects to test residual activity. Acute effects (combined mortality and knockdown) varied by insecticide, residue age, and natural enemy species. Broad-spectrum insecticides caused high mortality to all biocontrol agents, whereas products approved for use in organic agriculture had little effect. The reduced-risk insecticide acetamiprid consistently caused significant acute effects, even after aging for 14 d. Methoxyfenozide, novaluron, and chlorantraniliprole, which also are classified as reduced-risk insecticides, had low toxicity, and along with the organic products could be compatible with biological control. This study provides information to guide blueberry growers in their selection of insecticides. Further research will be needed to determine whether adoption of a pest management program based on the use of more selective insecticides will result in higher levels of biological control in blueberry.

  8. Critical evaluation of some equilibrium constants involving organophosphorus extractants

    CERN Document Server

    Marcus, Y

    2013-01-01

    Critical Evaluation of Some Equilibrium Constants Involving Organophosphorus Extractants is a supplementary text to the compilation ""Equilibrium Constants of Liquid-Liquid Distribution Reactions (Introduction, and Part I: Organophosphorus Extractants).The book contains a number of well documented chemical reactions that are critically evaluated. The reactions evaluated comprise those from List 1 for which data are available. There are, however, a great variety of reactions that cannot be critically evaluated due to lack of experimental data and unverifiable results.Chemists will find this com

  9. Mechanism and kinetic properties for OH-initiated atmospheric degradation of the organophosphorus pesticide diazinon

    Science.gov (United States)

    Zhou, Qin; Sun, Xiaoyan; Gao, Rui; Hu, Jingtian

    2011-06-01

    Diazinon is a member of the organophosphorus class of insecticides. It has been regarded as an important atmospheric pollutant because of its high detection-frequency in the air and potential adverse effects on humans and wildlife. In this paper, the reaction mechanism and possible degradation products for the OH-initiated atmospheric degradation of diazinon were investigated and the rate constants of crucial elementary steps over the temperature range of 180-370 K were predicted. Present results show that OH addition to C4 atom in the pyrimidyl ring, H abstraction from the -CH- moiety as well as OH addition to P atom are the dominant pathways for the reaction of diazinon with OH radicals. The dominant degradation products are diazoxon, SO 2, P3, CH 3CHO, P4, CH 3CO, P14 as well as CH 3CHCH 3. This work provides a comprehensive investigation of the OH-initiated atmospheric degradation of diazinon and should help to clarify its potential risk to non-targets.

  10. Animal models that best reproduce the clinical manifestations of human intoxication with organophosphorus compounds.

    Science.gov (United States)

    Pereira, Edna F R; Aracava, Yasco; DeTolla, Louis J; Beecham, E Jeffrey; Basinger, G William; Wakayama, Edgar J; Albuquerque, Edson X

    2014-08-01

    The translational capacity of data generated in preclinical toxicological studies is contingent upon several factors, including the appropriateness of the animal model. The primary objectives of this article are: 1) to analyze the natural history of acute and delayed signs and symptoms that develop following an acute exposure of humans to organophosphorus (OP) compounds, with an emphasis on nerve agents; 2) to identify animal models of the clinical manifestations of human exposure to OPs; and 3) to review the mechanisms that contribute to the immediate and delayed OP neurotoxicity. As discussed in this study, clinical manifestations of an acute exposure of humans to OP compounds can be faithfully reproduced in rodents and nonhuman primates. These manifestations include an acute cholinergic crisis in addition to signs of neurotoxicity that develop long after the OP exposure, particularly chronic neurologic deficits consisting of anxiety-related behavior and cognitive deficits, structural brain damage, and increased slow electroencephalographic frequencies. Because guinea pigs and nonhuman primates, like humans, have low levels of circulating carboxylesterases-the enzymes that metabolize and inactivate OP compounds-they stand out as appropriate animal models for studies of OP intoxication. These are critical points for the development of safe and effective therapeutic interventions against OP poisoning because approval of such therapies by the Food and Drug Administration is likely to rely on the Animal Efficacy Rule, which allows exclusive use of animal data as evidence of the effectiveness of a drug against pathologic conditions that cannot be ethically or feasibly tested in humans.

  11. Urinary Concentrations of Dialkylphosphate Metabolites of Organophosphorus Pesticides: National Health and Nutrition Examination Survey 1999–2004

    Directory of Open Access Journals (Sweden)

    Maribel Gallegos

    2011-07-01

    Full Text Available Organophosphorus (OP insecticides were among the first pesticides that EPA reevaluated as part of the Food Quality Protection Act of 1996. Our goal was to assess exposure to OP insecticides in the U.S. general population over a six-year period. We analyzed 7,456 urine samples collected as part of three two-year cycles of the National Health and Nutrition Examination Survey (NHANES from 1999–2004. We measured six dialkylphosphate metabolites of OP pesticides to assess OP pesticide exposure. In NHANES 2003–2004, dimethylthiophosphate was detected most frequently with median and 95th percentile concentrations of 2.03 and 35.3 µg/L, respectively. Adolescents were two to three times more likely to have diethylphosphate concentrations above the 95th percentile estimate of 15.5 µg/L than adults and senior adults. Conversely, for dimethyldithiophosphate, senior adults were 3.8 times and 1.8 times more likely to be above the 95th percentile than adults and adolescents, respectively, while adults were 2.1 times more likely to be above the 95th percentile than the adolescents. Our data indicate that the most vulnerable segments of our population—children and older adults—have higher exposures to OP pesticides than other population segments. However, according to DAP urinary metabolite data, exposures to OP pesticides have declined during the last six years at both the median and 95th percentile levels.

  12. Urinary Concentrations of Dialkylphosphate Metabolites of Organophosphorus Pesticides: National Health and Nutrition Examination Survey 1999–2004

    Science.gov (United States)

    Barr, Dana Boyd; Wong, Lee-Yang; Bravo, Roberto; Weerasekera, Gayanga; Odetokun, Martins; Restrepo, Paula; Kim, Do-Gyun; Fernandez, Carolina; Whitehead, Ralph D.; Perez, Jose; Gallegos, Maribel; Williams, Bryan L.; Needham, Larry L.

    2011-01-01

    Organophosphorus (OP) insecticides were among the first pesticides that EPA reevaluated as part of the Food Quality Protection Act of 1996. Our goal was to assess exposure to OP insecticides in the U.S. general population over a six-year period. We analyzed 7,456 urine samples collected as part of three two-year cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999–2004. We measured six dialkylphosphate metabolites of OP pesticides to assess OP pesticide exposure. In NHANES 2003–2004, dimethylthiophosphate was detected most frequently with median and 95th percentile concentrations of 2.03 and 35.3 μg/L, respectively. Adolescents were two to three times more likely to have diethylphosphate concentrations above the 95th percentile estimate of 15.5 μg/L than adults and senior adults. Conversely, for dimethyldithiophosphate, senior adults were 3.8 times and 1.8 times more likely to be above the 95th percentile than adults and adolescents, respectively, while adults were 2.1 times more likely to be above the 95th percentile than the adolescents. Our data indicate that the most vulnerable segments of our population—children and older adults—have higher exposures to OP pesticides than other population segments. However, according to DAP urinary metabolite data, exposures to OP pesticides have declined during the last six years at both the median and 95th percentile levels. PMID:21909292

  13. Synthesis of novel organo-phosphorus C60 dimers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Carbon bridged organophosphorus C60 dimers were obtained by the reaction of aminome- thylenebisphosphonate anion with C60 and fully characterized by 1HNMR, 31PNMR, 13CNMR, FT- MALDI-MS, FT-IR, UV-Vis, DEPT and HMBC, and the dimeric compounds undergo hydrolysis by using TMSI.

  14. Relieving Mipafox Inhibition in Organophosphorus Acid Anhydrolase by Rational Design

    Science.gov (United States)

    2013-03-01

    variant proteins. For each, an Escherichia coli DH5 culture containing one of the plasmids was grown at 37C in 1L of Luria -Bertani (LB) broth...inhibition constant LB Luria -Bertani (broth) OPPA organophosphorus acid anhydrolase SDS-PAGE sodium dodecylsulfate-polyacrylamide gel electrophoresis

  15. Quantitative structure-toxicity relationship (QSTR) studies on the organophosphate insecticides.

    Science.gov (United States)

    Can, Alper

    2014-11-01

    Organophosphate insecticides are the most commonly used pesticides in the world. In this study, quantitative structure-toxicity relationship (QSTR) models were derived for estimating the acute oral toxicity of organophosphate insecticides to male rats. The 20 chemicals of the training set and the seven compounds of the external testing set were described by means of using descriptors. Descriptors for lipophilicity, polarity and molecular geometry, as well as quantum chemical descriptors for energy were calculated. Model development to predict toxicity of organophosphate insecticides in different matrices was carried out using multiple linear regression. The model was validated internally and externally. In the present study, QSTR model was used for the first time to understand the inherent relationships between the organophosphate insecticide molecules and their toxicity behavior. Such studies provide mechanistic insight about structure-toxicity relationship and help in the design of less toxic insecticides.

  16. Pyrethroid insecticides in urban salmon streams of the Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Weston, D.P., E-mail: dweston@berkeley.edu [Department of Integrative Biology, University of California, 3060 Valley Life Sciences Bldg., Berkeley, CA 94720-3140 (United States); Asbell, A.M., E-mail: aasbell@berkeley.edu [Department of Integrative Biology, University of California, 3060 Valley Life Sciences Bldg., Berkeley, CA 94720-3140 (United States); Hecht, S.A., E-mail: scott.hecht@noaa.gov [NOAA Fisheries, Office of Protected Resources, 510 Desmond Drive S.E., Lacey, WA 98503 (United States); Scholz, N.L., E-mail: nathaniel.scholz@noaa.gov [NOAA Fisheries, Northwest Fisheries Science Center, 2725 Montlake Blvd. E., Seattle, WA 98112 (United States); Lydy, M.J., E-mail: mlydy@siu.edu [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University, 171 Life Sciences II, Carbondale, IL 62901 (United States)

    2011-10-15

    Urban streams of the Pacific Northwest provide spawning and rearing habitat for a variety of salmon species, and food availability for developing salmon could be adversely affected by pesticide residues in these waterbodies. Sediments from Oregon and Washington streams were sampled to determine if current-use pyrethroid insecticides from residential neighborhoods were reaching aquatic habitats, and if they were at concentrations acutely toxic to sensitive invertebrates. Approximately one-third of the 35 sediment samples contained measurable pyrethroids. Bifenthrin was the pyrethroid of greatest concern with regards to aquatic life toxicity, consistent with prior studies elsewhere. Toxicity to Hyalella azteca and/or Chironomus dilutus was found in two sediment samples at standard testing temperature (23 deg. C), and in one additional sample at a more environmentally realistic temperature (13 deg. C). Given the temperature dependency of pyrethroid toxicity, low temperatures typical of northwest streams can increase the potential for toxicity above that indicated by standard testing protocols. - Highlights: > Salmon-bearing creeks can be adversely impacted by insecticides from urban runoff. > Pyrethroid insecticides were found in one-third of the creeks in Washington and Oregon. > Two creeks contained concentrations acutely lethal to sensitive invertebrates. > Bifenthrin was of greatest concern, though less than in prior studies. > Standard toxicity testing underestimates the ecological risk of pyrethroids. - Pyrethroid insecticides are present in sediments of urban creeks of Oregon and Washington, though less commonly than in studies elsewhere in the U.S.

  17. Hydrocarbon insecticides: their risks for environment and human health.

    Science.gov (United States)

    El-Bahnasawy, Mamdouh M; Mohammad, Amina El-Hosini; Morsy, Tosson A

    2014-08-01

    Insecticides are used to control diseases spread by arthropods, but theys vary greatly in toxicity. Toxicity depends on the chemical and physical properties of a substance, and may be defined as the quality of being poisonous or harmful to animals or plants. Poisons have many different modes of action, but in general cause biochemical changes which interfere with normal body functions. Toxicity can be either acute or chronic. Acute toxicity is the ability of a substance to cause harmful effects which develop rapidly following absorption, i.e. a few hours or a day. Chronic toxicity is the ability of a substance to cause adverse health effects resulting from long-term exposure to a substance. There is a great range in the toxicity of insecticides to humans. The relative hazard of an insecticide is dependent upon the toxicity of the pesticide, the dose received and the length of time exposed. A hazard can be defined as a source of danger. The great majority of insecticides are poisonous to man and his beneficial insects and animals and are carcinogenic agents particularly, the halogenated hydrocarbons containing benzene ring.

  18. Sublethal effects of some botanical and chemical insecticides on the cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-09-01

    Full Text Available In addition to direct mortalities caused by acute concentrations of insecticides, some biological traits of target pests may be also affected by sublethal doses. The cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae is an important pest of a wide variety of agricultural crops across the world. The control of B. tabaci largely relies on wide application of chemical insecticides. In this study, we analyzed the life table parameters to evaluate the sublethal effect of three plant-derived insecticides (Fumaria parviflora (Fumariaceae, Teucrium polium (Lamiaceae, and Thymus vulgaris (Lamiaceae and two chemical insecticides (pymetrozin and neemarin on B. tabaci. The whiteflies were allowed to oviposit on plants infected with each of the five insecticides using leaf-dip method. The data were analyzed using the age-stage two-sex life table. We found significant differences in the gross reproductive rate (GRR, the net reproductive rat (R0, the intrinsic rate of increase (r and the finite rate of increase (λ of treated whiteflies compared to control. Our results showed that some biological traits of B. tabaci are affected by sub-lethal doses of the plant-derived extracts and that these effects are comparable to those of chemical insecticides. Given the detrimental effects of chemical insecticides on human, environment and non-target organisms, plant-derived insecticides may provide valuable environmentally friendly tools for pest management programs.

  19. A renaissance for botanical insecticides?

    Science.gov (United States)

    Isman, Murray B

    2015-12-01

    Botanical insecticides continue to be a subject of keen interest among the international research community, reflected in the steady growth in scientific publications devoted to the subject. Until very recently though, the translation of that theory to practice, i.e. the commercialisation and adoption of new botanical insecticides in the marketplace, has seriously lagged behind. Strict regulatory regimes, long the bane of small pesticide producers, are beginning to relax some of the data requirements for 'low-risk' pesticide products, facilitating movement of more botanicals into the commercial arena. In this paper I discuss some of the jurisdictions where botanicals are increasingly finding favour, some of the newer botanical insecticides in the plant and animal health arsenal and some of the specific sectors where botanicals are most likely to compete effectively with other types of insecticidal product.

  20. Large Enhancement of Optical Nonlinearities of New Organophosphorus Fullerene Derivative

    Institute of Scientific and Technical Information of China (English)

    刘智波; 田建国; 臧维平; 周文远; 张春平; 郑建禺; 周迎春; 徐华

    2003-01-01

    Optical nonlinearities of new organophosphorus fullerene derivative were determined by the Z-scan method with a pulsed Q-switch Nd:YAG laser at 532nm. The experimental results demonstrated that the derivative has much larger excited-states nonlinear absorption and nonlinear refraction than C60. A five-level model was utilized to fit the experimental data, and a good agreement is reached. Some parameters such as excited-state absorption cross and refraction cross were obtained. To our knowledge, the excited-state cross section of new organophosphorus fullerene derivative and its effective ratio to the ground-state cross section are the largest values among the fullerene derivatives reported to date.

  1. The application of green chemistry methods in organophosphorus synthesis

    Science.gov (United States)

    Odinets, Irina L.; Matveeva, E. V.

    2012-03-01

    Data concerning the synthesis of organophosphorus compounds in ionic liquids, in water and under solvent-free conditions are considered and summarized. It is shown that this strategy, which complies with the definition of green chemistry, has advantages in terms of the rate of the process and the yields of target products as compared with syntheses in common organic solvents. The Wittig, Horner-Wadsworth-Emmons, Kabachnik-Fields, Arbuzov and Michaelis reactions are considered as examples. The bibliography includes 178 references.

  2. Depression of plasma luteinizing hormone concentration in quail by the anticholinesterase insecticide parathion

    Science.gov (United States)

    Rattner, B.A.; Clarke, R.N.; Ottinger, M.A.

    1986-01-01

    To examine the effects of parathion on basal plasma luteinizing hormone (LH) concentration, male Japanese quail (Coturnix japonica) were orally intubated with 0, 5 or 10 mg/kg parathion and sacrificed after 4, 8 and 24 hr. At the 5 mg/kg dose, plasma LH levels were reduced at 4 and 8 hr, but returned to control values by 24 hr. Brain acetylcholinesterase activity was substantially reduced by 10 mg/kg parathion (52, 75 and 37% inhibition at 4, 8 and 24 hr, respectively) and plasma LH concentration remained depressed through the 24-hr period. These findings suggest that the organophosphorus insecticide parathion may alter plasma LH concentration in a manner which might impair reproductive activity, and provide indirect evidence for a cholinergic component in the regulation of LH secretion in quail.

  3. Synthesis of insecticidal sucrose esters

    Institute of Scientific and Technical Information of China (English)

    Song Zi-juan; Li Shu-jun; Chen Xi; Liu Li-mei; Song Zhan-qian

    2006-01-01

    Some synthetic sucrose esters (SE) are a relatively new class of insecticidal compounds produced by reacting sugars with fatty acids, which are safe for the environment. Especially, sucrose esters composed of C6-C12 fatty acids have desirable insecticidal properties against many soft-bodied arthropod pests. In our study, sucrose octanoate which has the highest activity against a range of arthropod species was synthesized by a trans-esterification method and proved its insecticidal property. Under the condition of a homogeneous liquid, sucrose octanoate was prepared by reacting ethyl octanoate with sucrose at reduced pressure; the yield was 79.11%. Sucrose octanoate synthesized was identified and its property analyzed by IR, TLC and spectrophotometric analysis. It was shown that the ratio of monoester to polyester in sucrose octanoate was 1.48:1. The insecticidal activity of the synthetic sucrose octanoate was evaluated at a concentration of 4 and 8 mg·mL-1. The mortality of first-instar larvae ofLymantria dispar from its contact toxicity was 72.5% after 36 hours, the revision insect reduced rate of Aphis glycines reached above 80% at 4 and 8 mg·mL-1 after being treated for 5 days. Since the SE products are nontoxic to humans and higher animals, fully biodegradable and hydrolyzed to readily metabolizable sucrose and fatty acid, they are not harmful to crops and appear to be good insecticide candidates.

  4. Effects of insecticide use on breeding birds in Christmas tree plantations in Quebec.

    Science.gov (United States)

    Rondeau, G; Desgranges, J L

    1995-10-01

    : This research, which was carried out in the spring of 1989 and 1990 in seven balsam fir (Abies balsamea) plantations in southeastern Quebec, examines potential deleterious effects of three insecticides (i.e. dimethoate, diazinon and insecticidal soap) on breeding American Robins (Turdus migratorius) (n=87 nests) and Song Sparrows (Melospizsa melodia) (n=41 nests). Through analyses of blood serum cholinesterases (AChE and BChE) activity both prior to and the second day following applications of the two organophosphorus insecticides, we showed that adult American Robins, Song Sparrows and Chipping Sparrows (Spizella passerina) breeding in the treated plantations were exposed to diazinon and dimethoate (p<0.05). Signs of exposure to diazinon (p<0.05) were also found in young American Robins. However, despite sharp reductions in blood ChE (and, in some cases, marked inhibition confirmed by 2-PAM reactivation), no cases of adult mortality were recorded following the treatments. Cases of complete or partial mortality were recorded in American Robin and Song Sparrow nests, even among control birds (non-exposed birds). No mortality was recorded for broods exposed to the insecticidal soap. Abandonment of nests and egg infertility were ruled out as possible causes of mortality. The cases of total mortality observed in American Robin and Song Sparrow broods exposed to dimethoate were similar to those recorded for control nests (18 and 25% compared to 14 and 21%, respectively). However, among American Robin and Song Sparrow nestlings exposed to diazinon, essentially twice as many cases of total mortality (31 and 38%, respectively) were recorded as for the control nests. It appears that American Robin eggs are sensitive to diazinon and dimethoate, particularly when spraying is carried out early in the incubation stage. In the case of the Song Sparrow, it is mainly the nestlings that succumb after diazinon is sprayed on them or when dimethoate applications are made during the

  5. Biodegradation and bioremediation potential of diazinon-degrading Serratia marcescens to remove other organophosphorus pesticides from soils.

    Science.gov (United States)

    Cycoń, Mariusz; Żmijowska, Agnieszka; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2013-03-15

    The ability of diazinon-degrading Serratia marcescens to remove organophosphorus pesticides (OPPs), i.e. chlorpyrifos (CP), fenitrothion (FT), and parathion (PT) was studied in a mineral salt medium (MSM) and in three soils of different characteristics. This strain was capable of using all insecticides at concentration of 50 mg/l as the only carbon source when grown in MSM, and 58.9%, 70.5%, and 82.5% of the initial dosage of CP, FT, and PT, respectively was degraded within 14 days. The biodegradation experiment showed that autochthonous microflora in all soils was characterized by a degradation potential of all tested OPPs; however, the initial lag phases for degradation of CP and FT, especially in sandy soil, were observed. During the 42-day experiment, 45.3%, 61.4% and 72.5% of the initial dose of CP, FT, and PT, respectively, was removed in sandy soil whereas the degradation of CP, FT, and PT in the same period, in sandy loam and silty soils reached 61.4%, 79.7% and 64.2%, and 68.9%, 81.0% and 63.6%, respectively. S. marcescens introduced into sterile soils showed a higher degradation potential (5-13%) for OPPs removal than those observed in non-sterile soil with naturally occurring attenuation. Inoculation of non-sterile soils with S. marcescens enhanced the disappearance rates of all insecticides, and DT50 for CP, FT, and PT was reduced by 20.7, 11.3 and 13.0 days, and 11.9, 7.0 and 8.1 days, and 9.7, 14.5 and 12.6 days in sandy, sandy loam, and silty soils, respectively, in comparison with non-sterile soils with only indigenous microflora. This ability of S. marcescens makes it a suitable strain for bioremediation of soils contaminated with OPPs.

  6. Development of a passive air sampler to measure airborne organophosphorus pesticides and oxygen analogs in an agricultural community.

    Science.gov (United States)

    Armstrong, Jenna L; Yost, Michael G; Fenske, Richard A

    2014-09-01

    Organophosphorus pesticides are some of the most widely used insecticides in the US, and spray drift may result in human exposures. We investigate sampling methodologies using the polyurethane foam passive air sampling device to measure cumulative monthly airborne concentrations of OP pesticides chlorpyrifos, azinphos-methyl, and oxygen analogs. Passive sampling rates (m(3)d(-1)) were determined using calculations using chemical properties, loss of depuration compounds, and calibration with side-by-side active air sampling in a dynamic laboratory exposure chamber and in the field. The effects of temperature, relative humidity, and wind velocity on outdoor sampling rates were examined at 23 sites in Yakima Valley, Washington. Indoor sampling rates were significantly lower than outdoors. Outdoor rates significantly increased with average wind velocity, with high rates (>4m(3)d(-1)) observed above 8ms(-1). In exposure chamber studies, very little oxygen analog was observed on the PUF-PAS, yet substantial amounts chlorpyrifos-oxon and azinphos methyl oxon were measured in outdoor samples. PUF-PAS is a practical and useful alternative to AAS because it results in little artificial transformation to the oxygen analog during sampling, it provides cumulative exposure estimates, and the measured sampling rates were comparable to rates for other SVOCs. It is ideal for community based participatory research due to low subject burden and simple deployment in remote areas.

  7. Tolerance to the carbamate insecticide propoxur.

    Science.gov (United States)

    Costa, L G; Hand, H; Schwab, B W; Murphy, S D

    1981-01-01

    Male mice were given the carbamate insecticide propoxur (2-isopropoxy phenyl methylcarbamate; Baygon) in the drinking water at weekly increasing concentrations (from 50 to 2000 ppm), for a period of 6 weeks. At the end of the treatment the LD50 for propoxur was significantly higher in the treated animals as compared with controls. Propoxur-treated animals were also resistant to the hypothermic effect of an acute administration of the same compound. Groups of mice were challenged with the cholinergic agonist carbachol at intervals during the drinking water dosing and at its end. No differences in sensitivity to carbachol acute toxicity were found between control and treated animals. Propoxur-tolerant animals were also not resistant to the hypothermic effect of oxotremorine, another cholinergic agonist. [3H]Quinuclidinyl benzilate ([3H]QNB) binding (a measure of muscarinic receptor density and affinity) in forebrain, hindbrain and ileum never differed in control and treated mice. The possibility that repeated administrations of propoxur induced increased metabolic inactivation was tested by measuring hexobarbital sleeping time and carboxylesterase activity in treated and control mice. No changes in tissue carboxylesterase activities occurred but hexobarbital sleeping time was significantly reduced in propoxur treated animals suggesting an induction of hepatic microsomal enzymes. These results suggest that tolerance to propoxur is not mediated by a decrease of cholinergic receptors, as reported for other acetylcholinesterase inhibitors, but possibly by an enhancement of its metabolism.

  8. AGE-RELATED EFFECTS OF CHLORPYRIFOS ON ACETYLCHOLINE RELEASE IN RAT BRAIN. (R825811)

    Science.gov (United States)

    Chlorpyrifos (CPF) is an organophosphorus insecticide that elicits toxicity through inhibition of acetylcholinesterase (AChE). Young animals are markedly more sensitive than adults to the acute toxicity of CPF. We evaluated acetylcholine (ACh) release and its muscarinic recept...

  9. Organophosphorus pesticides effect on early stages of the axolotl Ambystoma mexicanum (Amphibia: Caudata).

    Science.gov (United States)

    Robles-Mendoza, C; García-Basilio, C; Cram-Heydrich, S; Hernández-Quiroz, M; Vanegas-Pérez, C

    2009-02-01

    Ambystoma mexicanum is an endemic salamander of Xochimilco, a wetland of the basin of Mexico valley. Nowadays, axolotl populations are decreasing due environmental stressors. Particularly, studies about organophosphorus pesticides (OPPs; i.e. chlorpyrifos and malathion) toxicity are of great importance due to their intensive use in agricultural activities in Xochimilco. Thus, the aim of this study was to evaluate under controlled conditions the toxicity of chlorpyrifos (CPF) and malathion (MLT) on embryos and larvae (stage 44 and 54) of A. mexicanum. Embryos and larvae were exposure 96h from 0.5 to 3mg CPFL(-1) and from 10 to 30mg MLTL(-1) in independent tests. Embryos at the end of this period were maintained 9d without pesticide in order to identify possible recuperation. Differences obtained in mortality, hatching success, development, morphological abnormalities, behaviour and activity, suggest that toxicity of CPF and MLT differs in embryos and larval stages. Embryos were less sensitive to OPPs acute exposure than axolotl larvae; additionally, toxicity of CPF in larval stages was greater than MLT. On the other hand, data obtained in axolotl embryos during the period of recuperation to CPF in particular as delay and inhibition of development, malformations and success of hatching, indicated that these responses turned out more sensitive than mortality. This study allowed to identify the toxicological potential of OPPs on early developmental stages of A. mexicanum and it is a valuable contribution for the future management of the axolotl wild population.

  10. Insecticide species sensitivity distributions: importance of test species selection and relevance to aquatic ecosystems

    NARCIS (Netherlands)

    Maltby, L.; Blake, N.; Brock, T.C.M.; Brink, van den P.J.

    2005-01-01

    Single-species acute toxicity data and (micro)mesocosm data were collated for 16 insecticides. These data were used to investigate the importance of test-species selection in constructing species sensitivity distributions (SSDs) and the ability of estimated hazardous concentrations (HCs) to protect

  11. Does Early-Life Exposure to Organophosphate Insecticides Lead to Prediabetes and Obesity?

    OpenAIRE

    Slotkin, Theodore A.

    2010-01-01

    Human exposures to organophosphate insecticides are ubiquitous. Although regarded as neurotoxicants, increasing evidence points toward lasting metabolic disruption from early-life organophosphate exposures. We gave neonatal rats chlorpyrifos, diazinon or parathion in doses devoid of any acute signs of toxicity, straddling the threshold for barely-detectable cholinesterase inhibition. Organophosphate exposure during a critical developmental window altered the trajectory of hepatic adenylyl cyc...

  12. The insecticidal effect of diatomaceous earth against adults and nymphs of Blattella germanica

    Institute of Scientific and Technical Information of China (English)

    Seyyed Akbar Hosseini; Sahar Bazrafkan; Hassan Vatandoost; Mohammad Reza Abaei; Mussa Soleimani Ahmadi; Maryam Tavassoli; Mansoreh Shayeghi

    2014-01-01

    Objective: To evaluate the insecticidal effect of diatomaceous earth (DE) against adults and nymphs of Blattella germanica.Methods:cockroaches. Two stages, nymph and adult, were exposed to six dose rates of the DE, 2.5, 5, 10, 15, 20 and 25 g/m2, at 24, 48 and 72 h exposure period. Mortality (number of dead cockroaches) was assessed after 24 h. Other exposed specimens were transferred to the beakers contained food and water for counting the retard mortality rate after 1 week. This cross sectional study has been done on the laboratory strain of German Results: Increasing in dose rates of DE increased mortality rate, so that the lowest and highest mortality rates were observed in 2.5 and 25 g/m2, respectively. The results of the statistical analysis showed no significant difference in the lethality of 50% of DE plus water on the German cockroach nymphs.Conclusions:Due to the resistance of German cockroach against organochloride organophosphorus, carbamate and pyrethriodes insecticides, it is suggested to use DE for insect’s control.

  13. Levels of organophosphorus pesticides in medicinal plants commonly consumed in Iran

    Directory of Open Access Journals (Sweden)

    Sarkhail Parisa

    2012-08-01

    Full Text Available Abstract The frequent occurrence of pesticide residues in herbal materials was indicated by previous studies. In this study, the concentration of some of the organophosphorus pesticides including parathion, malathion, diazinon and pirimiphos methyl in different kinds of medicinal plants were determined. The samples were collected randomly from ten local markets of different areas of Iran. At the detection limit of 0.5 ng g-1, parathion and pirimiphos methyl were not detected in any of the samples. Some amounts of malathion and diazinon were found in Zataria, Matricaria chamomile, Spearmint and Cumin Seed samples while, the concentrations of target organophosphorus pesticides in Borage samples were below the detection limits of the methods which could be a result of intensive transformation of organophosphorus pesticides by Borage. In addition the organophosphorus pesticides were detected in all of the samples below the maximum residue levels (MRLs proposed by the international organizations.

  14. Cumulative risk assessment of the intake of organophosphorus and carbamate pesticides in the Danish diet

    DEFF Research Database (Denmark)

    Jensen, A. F.; Petersen, Annette; Granby, Kit

    2003-01-01

    The aim of the study is to evaluate the potential cumulative effects of organophosphorus and carbamate pesticides that act through a common mechanism of toxicity, and to assess the long- and short-term risks for the Danish population. The intake estimates are based on dietary intake data collected...... in the Danish nation-wide food consumption survey in 1995. The pesticide data are based on the Danish pesticide residue-monitoring programme from 1996-2001. The amount of 35 organophosphorus pesticides and carbamates were included in the cumulative risk assessment. Processing factors, such as reduction...... of pesticide levels by rinsing and peeling, were applied in the exposure assessment. The "Toxicity Equivalence Factor" (TEF) approach was used to normalise the toxicity of the different organophosphorus and carbamate pesticides. Cumulative chronic exposure of organophosphorus and carbamates pesticides via...

  15. Organophosphorus Compound DEPBT as a Coupling Reagent for Oligopeptides and Peptoids Synthesis: Studies on Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Some oligopeptidcs and peptoids were synthesized by applying the organophosphorus compound DEPBT as a coupling rcagent. D-Biotin-OOBt was obtained unexpcctcdly. A proposed reaction mechanism for DEPBT-mediated coupling was proved.

  16. Striatal dopaminergic pathways as a target for the insecticides permethrin and chlorpyrifos.

    Science.gov (United States)

    Karen, D J; Li, W; Harp, P R; Gillette, J S; Bloomquist, J R

    2001-12-01

    Because insecticide exposure has been linked to both Parkinsons disease and Gulf War illness, the neurotoxic actions of pyrethroid and organophosphate insecticides on behavior and striatal dopaminergic pathways were investigated in C57BL/6 mice treated with permethrin (three i.p. doses at 0.2-200 mg/kg) or chlorpyrifos (three s.c. doses at 25-100 mg/kg) over a 2-week period. Permethrin altered maximal [3H]dopamine uptake in striatal synaptosomes from treated mice, with changes in Vmax displaying a bell-shaped curve. Uptake was increased to 134% of control at a dose of 1.5 mg/kg. At higher doses of PM (25 mg/kg), dopamine uptake declined to a level significantly below that of control (50% of control at 200 mg/kg, P < 0.01). We also observed a small, but statistically significant decrease in [3H]dopamine uptake by chlorpyrifos, when given at a dose of 100 mg/kg. There was no significant effect on the Km for dopamine transport. Evidence of cell stress was observed in measures of mitochondrialfunction, which were reduced in mice given high-end doses of chlorpyrifos and permethrin. Although cytotoxicity was not reflected in decreased levels of striatal dopamine in either 200 mg/kg PM or 100 mg/kg CPF treatment groups, an increase in dopamine turnover at 100 mg/kg CPF was indicated by a significant increase in titers of the dopamine metabolite, 3,4-dihydroxyphenylacetic acid. Both permethrin and chlorpyrifos caused a decrease in open field behavior at the highest doses tested. Although frank Parkinsonism was not observed, these findings confirm that dopaminergic neurotransmission is affected by exposure to pyrethroid and organophosphorus insecticides, and may contribute to the overall spectrum of neurotoxicity caused by these compounds.

  17. Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

    Directory of Open Access Journals (Sweden)

    K. J. G. Díaz-Resendiz

    2015-01-01

    Full Text Available Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed.

  18. Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

    Science.gov (United States)

    Díaz-Resendiz, K. J. G.; Toledo-Ibarra, G. A.; Girón-Pérez, M. I.

    2015-01-01

    Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems) on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed. PMID:25973431

  19. A nano-silver enzyme electrode for organophosphorus pesticide detection.

    Science.gov (United States)

    Zheng, Qiqi; Yu, Yonghua; Fan, Kai; Ji, Feng; Wu, Jian; Ying, Yibin

    2016-08-01

    A nano-silver electrode immobilizing acetylcholinesterase (AChE) for the detection of organophosphorus (OPPs) pesticides is reported. Scanning electron microscopy (SEM) was used to characterize the surface structure of two kinds of electrodes fabricated with different sizes of silver powders and the interface between chitosan layer and nano-silver powder layer. Cyclic voltammetry was carried out to characterize the response of silver/chitosan electrode in the absence and in the presence of thiocholine (TCh). It was also used to evaluate the insulativity of the chitosan layer. An amperometric method was performed to measure the response of the electrode to TCh, which is the product of the enzymatic reaction for detecting organophosphorus pesticides indirectly. Although there are many kinds of nanoparticles, silver was chosen for its internal advantage in detecting TCh at low potential without further modification. The result shows nano-silver powder has better performance than usual silver powder, and the limit of detection of paraoxon is 4 ppb under optimized conditions. One percent (w/v) chitosan solution was used as binder for the immobilization of nano-silver powder and AChE, which made it possible for independent electrode fabrication at room temperature, whereas 3% (w/v) chitosan solution was used as insulating compound for controlling the electrode area. Unlike traditional organic insulating ink, chitosan is safe and environmentally friendly, and it is used as insulating material for the first time. The flexible nano-silver/AChE/chitosan electrode was evaluated in Chinese chives and cabbage, and the recoveries of standard addition were 105.11 and 96.41%, respectively. Owing to the antibacterial property of nano-silver and the biocompatibility, safety, and biodegradability of chitosan, the proposed method is safe, facile, environmentally friendly, and has great potential in organophosphorus pesticide detection for food safety. Graphical Abstract Current

  20. A critical review of neonicotinoid insecticides for developmental neurotoxicity.

    Science.gov (United States)

    Sheets, Larry P; Li, Abby A; Minnema, Daniel J; Collier, Richard H; Creek, Moire R; Peffer, Richard C

    2016-02-01

    A comprehensive review of published and previously unpublished studies was performed to evaluate the neonicotinoid insecticides for evidence of developmental neurotoxicity (DNT). These insecticides have favorable safety profiles, due to their preferential affinity for nicotinic receptor (nAChR) subtypes in insects, poor penetration of the mammalian blood-brain barrier, and low application rates. Nevertheless, examination of this issue is warranted, due to their insecticidal mode of action and potential exposure with agricultural and residential uses. This review identified in vitro, in vivo, and epidemiology studies in the literature and studies performed in rats in accordance with GLP standards and EPA guidelines with imidacloprid, acetamiprid, thiacloprid, clothianidin, thiamethoxam, and dinotefuran, which are all the neonicotinoids currently registered in major markets. For the guideline-based studies, treatment was administered via the diet or gavage to primiparous female rats at three dose levels, plus a vehicle control (≥20/dose level), from gestation day 0 or 6 to lactation day 21. F1 males and females were evaluated using measures of motor activity, acoustic startle response, cognition, brain morphometry, and neuropathology. The principal effects in F1 animals were associated with decreased body weight (delayed sexual maturation, decreased brain weight, and morphometric measurements) and acute toxicity (decreased activity during exposure) at high doses, without neuropathology or impaired cognition. No common effects were identified among the neonicotinoids that were consistent with DNT or the neurodevelopmental effects associated with nicotine. Findings at high doses were associated with evidence of systemic toxicity, which indicates that these insecticides do not selectively affect the developing nervous system.

  1. Possible mechanisms for sensitivity to organophosphorus and carbamate insecticides in eastern screech-owls and American kestrels

    Science.gov (United States)

    Vyas, N.B.; Thiele, L.A.; Garland, S.C.

    1998-01-01

    Effects of a single dietary exposure to fenthion and carbofuran on the survival, feeding behavior and brain ChE activity of eastern screech-owls, Otus asio and American kestrels, Falco sparverius, were evaluated. Birds were exposed to fenthion (23.6189.0 ppm) or carbofuran (31.7253.6 ppm) via meatballs. Carbofuran-exposed owls ate either = 80% of the meatball whereas all kestrels ate depression in determining the sensitivity of an animal may be species-specific.

  2. IMPROVED CLEANUP AND DETERMINATION METHOD OF DIALKYL PHOSPHATES IN THE URINE OF CHILDREN EXPOSED TO ORGANOPHOSPHORUS INSECTICIDES. (R825171)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. Application of a novel superposition technique to the structure of an organophosphorus insecticide and an organometallic compound

    Energy Technology Data Exchange (ETDEWEB)

    Beckman, D.E.

    1979-01-01

    The structures of 0-0-dimethyl-0-(3,5,6-trichloro-2-pyridyl) phosphorothioate (Dowco 214) and dicarbonylbis(eta-cyclopentadienyl)-..mu..-carbonyl-..mu..-thiocarbonyldiiron have been solved by single crystal x-ray diffraction and use of a modified Patterson superposition technique that uses two multiple vectors to define a structural parallelogram. This method results in a simpler and more accurate shift vector position determination and a general improvement in map clarity. Dowco 214 crystallizes in the space group P/sub 1//sup -/ with a = 11.598(2) A, b = 13.619(3) A, c = 8.281(1) A, ..cap alpha.. = 94.65(1)/sup 0/, ..beta.. = 94.87(2)/sup 0/, ..gamma.. = 79.97(2)/sup 0/ and four molecules per cell (two per asymmetric unit). A CNDO II calculation was performed and partial charge densities assigned. The molecule contains distances between positively charged centers that correspond well to the reported anionic-esteratic distance (a possible reaction variable) in AChE. Additional reaction variables are discussed. Cp/sub 2/Fe/sub 2/(CO)/sub 3/CS crystallizes in the space group P2/sub 1//c with a = 14.508(8) A, b = 13.618(5) A, c = 15.193(7) A, ..beta.. = 110.50(6)/sup 0/ and eight molecules per unit cell (two per asymmetric unit). The compound contains both a carbonyl and thiocarbonyl bridge and ..pi..-bonded cyclopentadienyl rings that are cis to one another. The iron--iron bond length is intermediate to that of its carbonyl and thiocarbonyl analogs.

  4. 棉蚜对12种杀虫剂的敏感性测定%Determination of Sensitivity of Aphis gossypii to 12 Insecticides

    Institute of Scientific and Technical Information of China (English)

    柳建伟; 张东海; 陈晋忠; 魏立强; 刘小宁; 张学涛

    2012-01-01

    [Aims] This experiments aimed to clear the sensitivity of cotton aphid in northern Xinjiang to insecticides used commonly in production and market. [Methods] The sensitivity of cotton aphid collected from 147 farm and Xinhu farm population were determined to twelve insecticides of four types by filter paper diffusion method respectively. [Results] The results showed that the sensitivity of two cotton aphid populations was the same to insecticides with the same type, and different to different types of insecticides, and high sensitivity to imidacloprid, thiamethoxam, avermectin, and lower sensitivity to pyrethroid and organophosphorus compounds. [Conclusions] According to the results, insecticide types, dosages and application frequency should be controlled strictly, in order to delay the resistance development of cotton aphid, and different insecticides should be applied alternately and mixed reasonably.%[目的]为探明新疆北部棉区棉蚜种群对市场上和生产中常用药剂的敏感性程度.[方法]采用滤纸药膜法分别测定了147团和新湖农场棉蚜种群对4大类杀虫剂中的12种常用药剂的敏感性.[结果]2个棉蚜种群对同类杀虫剂的敏感度基本一致,对不同杀虫剂敏感性有较大差异.对吡虫啉、噻虫嗪、阿维菌素敏感性高,对菊酯类和有机磷类药剂敏感性低.[结论]根据测定结果,生产中应严格控制用药种类以及施药量和施药次数,选用不同类型杀虫剂轮用或混用,以延缓棉蚜抗性发展.

  5. Environmental Fate of Organophosphorus Compounds Related to Chemical Weapons

    Energy Technology Data Exchange (ETDEWEB)

    Davisson, M L; Love, A H; Vance, A; Reynolds, J G

    2005-02-08

    Man-made organophosphorus compounds have been widely distributed throughout our environment as pesticides since their development during and after WWII. Many important studies have documented their relative persistence and toxicity. Development and use of some organophosphorus compounds as nerve agents gave rise to a separate but parallel effort to understand environmental persistence. In this latter case, the experiments have focused mainly on evaporation rates and first-order reaction kinetics. However, because organophosphorus compounds are easily polarized, the ionic content of a surrounding media directly factors into these reaction rates, but limited work in this regard has been done under environmentally relevant conditions. Furthermore, limited experiments investigating persistence of these agents on soil has resulted in widely varying degradation rates. Not surprisingly, no studies have investigated affinities of organophosphorus nerve agents to mineral or organic matter typically found in soil. As a result, we initiated laboratory experiments on dilute concentrations of nerve agent O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX) to quantify persistence in simulated environmental aqueous conditions. A quantitative analytical method was developed for VX and its degradation products using High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). VX hydrolysis rate is known to have a pH-dependency, however, the type of buffer and the relative proportion of different nucleophiles in solution significantly affect the overall rate and mechanism of degradation. For example, dissolved carbonate, a weak nucleophile dominating natural water, yielded pseudo-first order rate constants of {approx} 8 x 10{sup -3}/hr at pH 5 and 2 x 10{sup -2}/hr at pH 11. This small pH-dependent variation departs significantly from widely accepted rates at this pH range (4 x 10{sup -4}/hr to 8 x 10{sup -2}/hr) that were based on

  6. Nanostructured carbon materials decorated with organophosphorus moieties: synthesis and application

    Science.gov (United States)

    Biagiotti, Giacomo; Langè, Vittoria; Ligi, Cristina; Caporali, Stefano; Muniz-Miranda, Maurizio; Flis, Anna; Pietrusiewicz, K Michał; Ghini, Giacomo; Brandi, Alberto

    2017-01-01

    A new synthetic approach for the production of carbon nanomaterials (CNM) decorated with organophosphorus moieties is presented. Three different triphenylphosphine oxide (TPPO) derivatives were used to decorate oxidized multiwalled carbon nanotubes (ox-MWCNTs) and graphene platelets (GPs). The TPPOs chosen bear functional groups able to react with the CNMs by Tour reaction (an amino group), nitrene cycloaddition (an azido group) or CuAAC reaction (one terminal C–C triple bond). All the adducts were characterized by FTIR, Raman spectroscopy, TEM, XPS, elemental analysis and ICP-AES. The cycloaddition of nitrene provided the higher loading on ox-MWCNTs and GPs as well, while the Tour approach gave best results with nanotubes (CNTs). Finally, we investigated the possibility to reduce the TPPO functionalized CNMs to the corresponding phosphine derivatives and applied one of the materials produced as heterogeneous organocatalyst in a Staudinger ligation reaction.

  7. Carbamate and Organophosphorus Nematicides: Acetylcholinesterase inhibition and Effects on Dispersal.

    Science.gov (United States)

    Pree, D J; Townshend, J L; Archibald, D E

    1989-10-01

    The sensitivities of acetylcholinesterases (ACHE) from the fungus-feeder Aphelenchus avenae and the plant-parasitic species Helicotylenchus dihystera and Pratylenchus penetrans and the housefly, Musca domestica, were compared using a radiometric assay which utilized H(3) acetylcholine as a substrate. Nematode ACHE were generally less sensitive to inhibition by organophosphorns and carbamate pesticides than were ACHE from the housefly. ACHE from the plant-parasitic species and A. avenae were generally similar in sensitivity. In soil, carbamates were more toxic than the organophosphorus pesticides to A. avenae. All pesticides tested affected nematode movement, but fenamiphos was more inhibitory than others. The effects on dispersal of nematodes may be an important mechanism in control by some nematicides.

  8. Fluorescent Chemosensors for Toxic Organophosphorus Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Kenneth Fletcher

    2010-07-01

    Full Text Available Many organophosphorus (OP based compounds are highly toxic and powerful inhibitors of cholinesterases that generate serious environmental and human health concerns. Organothiophosphates with a thiophosphoryl (P=S functional group constitute a broad class of these widely used pesticides. They are related to the more reactive phosphoryl (P=O organophosphates, which include very lethal nerve agents and chemical warfare agents, such as, VX, Soman and Sarin. Unfortunately, widespread and frequent commercial use of OP-based compounds in agricultural lands has resulted in their presence as residues in crops, livestock, and poultry products and also led to their migration into aquifers. Thus, the design of new sensors with improved analyte selectivity and sensitivity is of paramount importance in this area. Herein, we review recent advances in the development of fluorescent chemosensors for toxic OP pesticides and related compounds. We also discuss challenges and progress towards the design of future chemosensors with dual modes for signal transduction.

  9. Pharmacophore model for neonicotinoid insecticides

    Institute of Scientific and Technical Information of China (English)

    Jian Li; Xiu Lian Ju; Feng Chao Jiang

    2008-01-01

    An effective prediction pharmacophore model (RMS = 0.634, Correl = 0.893, Weight = 1.463, Config = 11.940) was success-fully obtained by 3D-QSAR based on a series of nAChR (nicotinic acetylcholine receptors) agonists, which consists of a hydrogen-bonding acceptor, a hydrogen-bond donor, a hydrophobic aliphatic and a hydrophobic aromatic centre. This pharmacophore modelmay provide theoretical basis for designation and development of higher active insecticides.2008 Xiu Lian Ju. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  10. Insecticide Recommendations for Arkansas. MP 144.

    Science.gov (United States)

    Jones, Bill F.; Barnes, Gordon

    This publication gives, in chart form, insecticides for use on animals, field crops, fruits, flowers, trees and shrubs, household pests, recreation areas, lawn and turf grass, pecans, stored grain, and vegetables. Included in the charts are the insecticides recommended for each insect, formulation to be used, amount, time to apply, and other…

  11. Insecticide Resistance Reducing Effectiveness of Malaria Control

    Centers for Disease Control (CDC) Podcasts

    2007-01-24

    Malaria prevention is increasingly insecticide based. Dr. John Gimnig, an entomologist with the Division of Parasitic Diseases, CDC, discusses evidence that mosquito resistance to insecticides, which is measured in the laboratory, could compromise malaria prevention in the field.  Created: 1/24/2007 by Emerging Infectious Diseases.   Date Released: 3/13/2007.

  12. A site-specific ecological risk assessment for corn-associated insecticides.

    Science.gov (United States)

    Whiting, Sara A; Lydy, Michael J

    2015-07-01

    A site-specific ecological risk assessment (ERA) was conducted to examine the simultaneous use of genetically modified corn (Bt corn) with a neonicotinoid seed coating, clothianidin, and use of a granular insecticide, tefluthrin, to protect crops from pest damage. A field study was conducted on site, and exposure data from the literature were summarized to determine the matrices and exposure concentrations that nontarget species could typically experience within an agricultural ecosystem. To determine ecological effects on nontarget species, acute toxicity bioassays were conducted on earthworms (Eisenia fetida), amphipods (Hyalella azteca), and Elmid riffle beetle larvae (Ancyronyx spp.) in which the test species were exposed to single insecticides as well as the mixture of the 3 insecticides. In the risk characterization section of the ERA, stressor-response profiles for each species tested were compared with field distributions of the insecticides, and a margin of safety at the 10th percentile (MOS10) was calculated to estimate risk. No acute toxicity was observed in any of the 3 nontarget species after exposure to senescent Bt corn leaf tissue. Large MOS10 values were calculated for clothianidin to the nontarget species. When bioassays were compared with tefluthrin field distributions, very low MOS10 values were calculated for earthworms (0.06) and H. azteca (0.08) because the environmental concentrations often exceeded the stressor-response profile. No increased toxicity was observed when nontarget species were exposed to a mixture of the 3 insecticides. In summary, the genetically modified corn insecticidal proteins and clothianidin were not found at environmental concentrations exceeding benchmark values for ecological effects, but tefluthrin was consistently detected in the environment at levels that could be causing toxicity to nontarget species, especially if this pyrethroid is able to travel off site.

  13. Multiple mitigation mechanisms: Effects of submerged plants on the toxicity of nine insecticides to aquatic animals.

    Science.gov (United States)

    Brogan, William R; Relyea, Rick A

    2017-01-01

    Understanding the processes that regulate contaminant impacts in nature is an increasingly important challenge. For insecticides in surface waters, the ability of aquatic plants to sorb, or bind, hydrophobic compounds has been identified as a primary mechanism by which toxicity can be mitigated (i.e. the sorption-based model). However, recent research shows that submerged plants can also rapidly mitigate the toxicity of the less hydrophobic insecticide malathion via alkaline hydrolysis (i.e. the hydrolysis-based model) driven by increased water pH resulting from photosynthesis. However, it is still unknown how generalizable these mitigation mechanisms are across the wide variety of insecticides applied today, and whether any general rules can be ascertained about which types of chemicals may be mitigated by each mechanism. We quantified the degree to which the submerged plant Elodea canadensis mitigated acute (48-h) toxicity to Daphnia magna using nine commonly applied insecticides spanning three chemical classes (carbamates: aldicarb, carbaryl, carbofuran; organophosphates: malathion, diazinon, chlorpyrifos; pyrethroids: permethrin, bifenthrin, lambda-cyhalothrin). We found that insecticides possessing either high octanol-water partition coefficients (log Kow) values (i.e. pyrethroids) or high susceptibility to alkaline hydrolysis (i.e. carbamates and malathion) were all mitigated to some degree by E. canadensis, while the plant had no effect on insecticides possessing intermediate log Kow values and low susceptibility to hydrolysis (i.e. chlorpyrifos and diazinon). Our results provide the first general insights into which types of insecticides are likely to be mitigated by different mechanisms based on known chemical properties. We suggest that current models and mitigation strategies would be improved by the consideration of both mitigation models.

  14. Organophosphorus pesticides decrease M2 muscarinic receptor function in guinea pig airway nerves via indirect mechanisms.

    Directory of Open Access Journals (Sweden)

    Becky J Proskocil

    Full Text Available BACKGROUND: Epidemiological studies link organophosphorus pesticide (OP exposures to asthma, and we have shown that the OPs chlorpyrifos, diazinon and parathion cause airway hyperreactivity in guinea pigs 24 hr after a single subcutaneous injection. OP-induced airway hyperreactivity involves M2 muscarinic receptor dysfunction on airway nerves independent of acetylcholinesterase (AChE inhibition, but how OPs inhibit neuronal M2 receptors in airways is not known. In the central nervous system, OPs interact directly with neurons to alter muscarinic receptor function or expression; therefore, in this study we tested whether the OP parathion or its oxon metabolite, paraoxon, might decrease M2 receptor function on peripheral neurons via similar direct mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: Intravenous administration of paraoxon, but not parathion, caused acute frequency-dependent potentiation of vagally-induced bronchoconstriction and increased electrical field stimulation (EFS-induced contractions in isolated trachea independent of AChE inhibition. However, paraoxon had no effect on vagally-induced bradycardia in intact guinea pigs or EFS-induced contractions in isolated ileum, suggesting mechanisms other than pharmacologic antagonism of M2 receptors. Paraoxon did not alter M2 receptor expression in cultured cells at the mRNA or protein level as determined by quantitative RT-PCR and radio-ligand binding assays, respectively. Additionally, a biotin-labeled fluorophosphonate, which was used as a probe to identify molecular targets phosphorylated by OPs, did not phosphorylate proteins in guinea pig cardiac membranes that were recognized by M2 receptor antibodies. CONCLUSIONS/SIGNIFICANCE: These data indicate that neither direct pharmacologic antagonism nor downregulated expression of M2 receptors contributes to OP inhibition of M2 function in airway nerves, adding to the growing evidence of non-cholinergic mechanisms of OP neurotoxicity.

  15. Molecular Descriptors Family on Structure Activity Relationships 4. Molar Refraction of Cyclic Organophosphorus Compounds

    Directory of Open Access Journals (Sweden)

    Lorentz JÄNTSCHI

    2005-06-01

    Full Text Available The molecular descriptors family on structure activity relationships methodology was applied on ten cyclic organophosphorus compounds in order to predict theirs molar refraction. A number of 107692 significantly different MDF members enter into a multiple linear regression analysis. A pair of descriptors (lGDmSMt, lAmrfEt, which have the best performing ability in prediction of molar refraction of cyclic organophosphorus compounds, was found and a bi-varied MDF SAR model was built. After performing leave-one-out cross-validation, satisfactory result was obtained with cross-validation r2cv and r2 values of 0.9999 and 0.9999. The external validation of the bi-varied MDF SAR model and its ability in prediction of molar refraction of cyclic organophosphorus compounds is demonstrated by the results obtained in training vs. test experiment. The correlated correlation results proved us that the ability in prediction of molar refraction of cyclic organophosphorus compounds with bi-varied MDF SAR model is significantly better compared with the previous reported SAR (see pZ = 0.0 % from Steiger’s Z test. The results showed clearly that the molar refraction of cyclic organophosphorus compounds is almost of topological nature (99.99%, and is strongly dependent on atomic relative mass and atomic electronegativity.

  16. An Indigenously Developed Insecticidal Aerosol

    Directory of Open Access Journals (Sweden)

    R. N. Varma

    1969-10-01

    Full Text Available A total of 6 "Test" insecticidal aerosols (TA-I to VI indigenously produced were tested during the years 1966-67 as suitable replacements for imported aerosols.TA-I produced deep yellow staining and a yellowish spray mist. Its capacity was only 120 ml fluid. TA-III types II and III containing modified aerosol formulation with "Esso solvent 3245" and mineral turpentine oil (Burmah Shelland Freon 12 11 (all indigenouswere comparable to he "SRA" in insecticidial efficacy. The container was also manufactured in the country and it compared well with the "SRA" in construction, resistance against rough usage and mechanical function. They were both finally approved for introduction in the services as replacement for imported aerosols. TA-IV performed well in inscticidial assessment, but the aerosols formulation. TA-V and VI were similar to TA-III types II and III respectively.

  17. Site-directed mutagenesis of an acetylcholinesterase gene from the yellow fever mosquito Aedes aegypti confers insecticide insensitivity.

    Science.gov (United States)

    Vaughan, A; Rocheleau, T; ffrench-Constant, R

    1997-11-01

    Insecticide resistance is a serious problem facing the effective control of insect vectors of disease. Insensitive acetylcholinesterase (AChE) confers resistance to organophosphorus (OP) and carbamate insecticides and is a widespread resistance mechanism in vector mosquitoes. Although the point mutations that underlie AChE insensitivity have been described from Drosophila, the Colorado potato beetle, and house flies, no resistance associated mutations have been documented from mosquitoes to date. We are therefore using a cloned acetylcholinesterase gene from the yellow fever mosquito Aedes aegypti as a model in which to perform site directed mutagenesis in order to understand the effects of potential resistance associated mutations. The same resistance associated amino-acid replacements as found in other insects also confer OP and carbamate resistance to the mosquito enzyme. Here we describe the levels of resistance conferred by different combinations of these mutations and the effects of these mutations on the kinetics of the AChE enzyme. Over-expression of these constructs in baculovirus will facilitate purification of each of the mutant enzymes and a more detailed analysis of their associated inhibition kinetics.

  18. Transient expression of organophosphorus hydrolase to enhance the degrading activity of tomato fruit on coumaphos

    Institute of Scientific and Technical Information of China (English)

    Jie-hong ZHAO; De-gang ZHAO

    2009-01-01

    We constructed an expression cassette of the organophosphorus pesticide degrading (opd)gene under the control of the E8 promoter.Then opd was transformed into tomato fruit using an agroinfiltration transient expression system.β-Glueuronidase (GUS) staining,reverse transcription-polymerase chain reaction (RT-PCR),wavelength scanning,and fluorescent reaction were performed to examine the expression of the opd gene and the hydrolysis activity on eoumaphos of organophosphorus hydrolase (OPH) in tomato fruit.The results show that the agroinfiltrated tomato fruit-expressed OPH had the maximum hydrolysis activity of about 11.59 U/mg total soluble protein.These results will allow us to focus on breeding transgenie plants that could not only enhance the degrading capability of fruit and but also hold no negative effects on pest control when spraying organophosphorus pesticides onto the seedlings in fields.

  19. Detoxification of organophosphorus pesticides and nerve agents through RSDL: efficacy evaluation by (31)P NMR spectroscopy.

    Science.gov (United States)

    Elsinghorst, Paul W; Worek, Franz; Koller, Marianne

    2015-03-04

    Intoxication by organophosphorus compounds, especially by pesticides, poses a considerable risk to the affected individual. Countermeasures involve both medical intervention by means of antidotes as well as external decontamination to reduce the risk of dermal absorption. One of the few decontamination options available is Reactive Skin Decontamination Lotion (RSDL), which was originally developed for military use. Here, we present a (31)P NMR spectroscopy based methodology to evaluate the detoxification efficacy of RSDL with respect to a series of organophosphorus pesticides and nerve agents. Kinetic analysis of the obtained NMR data provided degradation half-lives proving that RSDL is also reasonably effective against organophosphorus pesticides. Unexpected observations of different RSDL degradation patterns are presented in view of its reported oximate-catalyzed mechanism of action.

  20. Organophosphorus reagents in actinide separations: Unique tools for production, cleanup and disposal

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K. L.

    2000-01-12

    Interactions of actinide ions with phosphate and organophosphorus reagents have figured prominently in nuclear science and technology, particularly in the hydrometallurgical processing of irradiated nuclear fuel. Actinide interactions with phosphorus-containing species impact all aspects from the stability of naturally occurring actinides in phosphate mineral phases through the application of the bismuth phosphate and PUREX processes for large-scale production of transuranic elements to the development of analytical separation and environment restoration processes based on new organophosphorus reagents. In this report, an overview of the unique role of organophosphorus compounds in actinide production, disposal, and environment restoration is presented. The broad utility of these reagents and their unique chemical properties is emphasized.

  1. Mutagenesis of organophosphorus hydrolase to enhance hydrolysis of the nerve agent VX.

    Science.gov (United States)

    Gopal, S; Rastogi, V; Ashman, W; Mulbry, W

    2000-12-20

    Organophosphorus hydrolase (OPH) is capable of hydrolyzing a wide variety of organophosphorus pesticides and chemical warfare agents. However, the hydrolytic activity of OPH against the warfare agent VX is less than 0.1% relative to its activity against parathion and paraoxon. Based on the crystal structure of OPH and the similarities it shares with acetylcholinesterase, eight OPH mutants were constructed with the goal of increasing OPH activity toward VX. The activities of crude extracts from these mutants were measured using VX, demeton-S methyl, diisopropylfluoro-phosphate, ethyl parathion, paraoxon, and EPN as substrates. One mutant (L136Y) displayed a 33% increase in the relative VX hydrolysis rate compared to wild type enzyme. The other seven mutations resulted in 55-76% decreases in the relative rates of VX hydrolysis. There was no apparent relationship between the hydrolysis rates of VX and the rates of the other organophosphorus compounds tested.

  2. Microsomal transformation of organophosphorus pesticides by white rot fungi.

    Science.gov (United States)

    Jauregui, Juan; Valderrama, Brenda; Albores, Arnulfo; Vazquez-Duhalt, Rafael

    2003-12-01

    The enzymatic mechanism for the transformation of organophosphorus pesticides (OPPs) by different white-rot fungi strains was studied. With the exception of Ganoderma applanatum 8168, all strains from a collection of 17 different fungi cultures were able to deplete parathion. Three strains showing the highest activities were selected for further studies: Bjerkandera adusta 8258, Pleurotus ostreatus 7989 and Phanerochaete chrysosporium 3641. These strains depleted 50 to 96% of terbufos, azinphos-methyl, phosmet and tribufos after four-days exposure to the pesticides. In order to identify the cellular localization of the transformation activity, the extracellular and microsomal fractions of Pleuronts ostreatus 7989 were evaluated in vitro. While the activities of ligninolytic enzymes (lignin peroxidase, manganese peroxidase and laccase) were detected in the extracellular fraction, no enzymatic modification of any of the five pesticides tested could be found, suggesting the intracellular origin of the transformation activity. In accordance with this observation the microsomal fraction was found able to transform three OPPs with the following rates: 10 micromol mg prot(-1) h(-1) for phosmet, 5.7 micromol mg prot(-1) h(-1) for terbufos, and 2.2 micromol mg prot(-1) h(-1) for azinphos-methyl. The products from these reactions and from the transformation of trichlorfon and malathion, were identified by mass-spectrometry. These results, supported by specific inhibition experiments and the stringent requirement for NADPH during the in vitro assays suggest the involvement of a cytochrome P450.

  3. Microchip-Based Organophosphorus Detection Using Bienzyme Bioelectrocatalysis

    Science.gov (United States)

    Han, Yong Duk; Jeong, Chi Yong; Lee, Jun Hee; Lee, Dae-Sik; Yoon, Hyun C.

    2012-06-01

    We have developed a microsystem for the detection of organophosphorus (OP) compounds using acetylcholine esterase (AchE) and choline oxidase (ChOx) bienzyme bioelectrocatalysis. Because AchE is irreversibly inhibited by OP pesticides, the change in AchE activity with OP treatment can be traced to determine OP concentration. Polymer-associated ChOx immobilization on the working electrode surface and magnetic microparticle (MP)-assisted AchE deposition methods were employed to create an AchE-ChOx bienzyme-modified biosensing system. ChOx was immobilized on the micropatterned electrodes using poly(L-lysine), glutaraldehyde, and amine-rich interfacial surface. AchE was immobilized on the MP surface via Schiff's base formation, and the enzyme-modified MPs were deposited on the working electrode using a magnet under the microfluidic channel. The bioelectrocatalytic reaction between AchE-ChOx bienzyme cascade and the ferrocenyl electron shuttle was successfully used to detect OP with the developed microchip. This provides a self-contained and relatively easy method for OP detection. It requires minimal time and a small sample size, and has potential analytic applications in pesticides and chemical warfare agents.

  4. Detection of Organophosphorus Pesticides with Colorimetry and Computer Image Analysis.

    Science.gov (United States)

    Li, Yanjie; Hou, Changjun; Lei, Jincan; Deng, Bo; Huang, Jing; Yang, Mei

    2016-01-01

    Organophosphorus pesticides (OPs) represent a very important class of pesticides that are widely used in agriculture because of their relatively high-performance and moderate environmental persistence, hence the sensitive and specific detection of OPs is highly significant. Based on the inhibitory effect of acetylcholinesterase (AChE) induced by inhibitors, including OPs and carbamates, a colorimetric analysis was used for detection of OPs with computer image analysis of color density in CMYK (cyan, magenta, yellow and black) color space and non-linear modeling. The results showed that there was a gradually weakened trend of yellow intensity with the increase of the concentration of dichlorvos. The quantitative analysis of dichlorvos was achieved by Artificial Neural Network (ANN) modeling, and the results showed that the established model had a good predictive ability between training sets and predictive sets. Real cabbage samples containing dichlorvos were detected by colorimetry and gas chromatography (GC), respectively. The results showed that there was no significant difference between colorimetry and GC (P > 0.05). The experiments of accuracy, precision and repeatability revealed good performance for detection of OPs. AChE can also be inhibited by carbamates, and therefore this method has potential applications in real samples for OPs and carbamates because of high selectivity and sensitivity.

  5. Photocolorimetric Biosensor for Detection of Cholinergic Organophosphorus Compounds

    Directory of Open Access Journals (Sweden)

    Kamila Vymazalová

    2012-11-01

    Full Text Available To detect nerve agents in practice, the analytical methods such as gas, liquid and thin-layer chromatography, mass spectrometry or capillary electrophoresis are usually used. Apart from these analytical methods, we developed an analytical device (tape photocolorimetric biosensor based on the modified Ellman's cholinesterase biochemical reaction for multidetection of cholinergic organophosphorus compounds. Enzyme butyrylcholinesterase was used as a biorecognizing component and its activity was evaluated by red, blue, green (RGB sensor. This method eliminates errors in the evaluation and provides automatic data collection with their subsequent evaluation. The unique method of dosing allows appropriate dispensing of reagents in microlitres volumes and the whole system is simple to operate. Suitability of the constructed biosensors was evaluated using the six organophosphates (Tabun, sarin, Soman, cyclosin, VX and R33 compound. Biosensor showed the ability to measure substances at concentrations ranging between ~ 1×10-8 mg/l - 1×10-6 mg/l in the air, according to their inhibition effect.Defence Science Journal, 2012, 62(6, pp.399-403, DOI:http://dx.doi.org/10.14429/dsj.62.2589

  6. Clinico-epidemiological characteristics of patients presenting with organophosphorus poisoning

    Directory of Open Access Journals (Sweden)

    Indranil Banerjee

    2012-01-01

    Full Text Available Background: Organophosphorus (OP poisoning is a major health problem all over the world, particularly in the developing countries. Aim: The present study aims to explore the clinical and epidemiological features found in patients presenting with OP poisoning. Materials and Methods: A 1-year cross-sectional study was conducted on patients presenting with clinical features of OP poisoning in a tertiary care medical college. Results: A total of 968 patients presented during the study period. Poisoning with suicidal intent (82.02% was more common than the accidental one (17.98%. Majority of the patients were housewives (42% followed by farmers, shopkeepers, laborers, students. Methyl parathion was the most common poison consumed by the patients (35.74% followed by diazinon, chlorpyriphos, dimicron. Nausea and vomiting (85.02% was the most common symptom while miosis was the most common sign observed in 91.94% patients. A total of 56 patients of OP poisoning died (5.78% with respiratory failure being the primary cause of death followed by CNS depression, cardiac arrest, and septicaemia. Conclusion: The present study showed that majority of the patients were of young age with females outnumbering males. Poisoning with suicidal intent was more common than accidental. Nausea and vomiting was the most common symptom reported by the patients while miosis was the most common sign observed by the treating physicians of the research team.

  7. Importance and toxicological effects of organophosphorus pesticides: A comprehensive review

    Directory of Open Access Journals (Sweden)

    M. Kazemi

    2012-09-01

    Full Text Available Environmental risk assessment is an estimate of the likelihood or probability of an adverse impact on the environment resulting from human activities such as applying of pesticides against of target pests (insects, plant pathogens, weeds, nematodes, microbes, mollusks, birds, mammals, fish and so on in the agriculture. Since the Withdrawal of organochlorine pesticides from use, organophosphorus pesticides (OPs have become the most widely used pesticides available today in the entire world especially in the Iran. The use of OPs has a number of health advantages, including control of insect vector borne diseases and increasing the food and agriculture productions. However, the use of these toxic compounds on man, animals or in his immediate environment has caused potential hazards that seriously are baneful for public health. There has been increasing awareness and concern on the part of food and health officials and of the dairy industry about the presence OPs in milk and other milk products. In this article, we reviewed some printed articles about OP poisoning and its management.

  8. Assessing transferable residues from intermittent exposure to flea control collars containing the organophosphate insecticide chlorpyrifos.

    Science.gov (United States)

    Chambers, Janice E; Boone, J Scott; Davis, M Keith; Moran, John E; Tyler, John W

    2007-11-01

    Children can be exposed to pesticides from numerous residential sources such as carpet, house dust, toys and clothing from treated homes, and flea control remedies on pets. In the present studies, 48 pet dogs (24 in each of two studies) of different breeds and weights were treated with over-the-counter flea collars containing chlorpyrifos (CP), an organophosphorus insecticide. Transferable insecticide residues were quantified on cotton gloves used to rub the dogs for 5 min and on cotton tee shirts worn by a child (Study 2 only). First morning urine samples were also obtained from adults and children in both studies for metabolite (3,5,6-trichloro-2-pyridinol) quantification. Blood samples were obtained from treated dogs in Study 1 and plasma cholinesterase (ChE) activity was monitored. Transferable residues on gloves for all compounds were highest near the neck of the dogs and were lowest in areas most distant from the neck. Rubbing samples (over the collar) at two weeks post-collar application contained 447+/-57 microg CP/glove while samples from the fur of the back contained 8+/-2 microg CP/glove. In Study 2, cotton tee shirts worn by children at 15 days post-collar application for 4 h showed CP levels of 134+/-66 ng/g shirt. There were significant differences between adults and children in the levels of urinary metabolites with children generally having higher urinary levels of metabolites than adults (grand mean+/-SE; 11.6+/-1.1 and 7.9+/-0.74 ng/mg creatinine for children and adults, respectively, compared to 9.4+/-0.8 and 6.9+/-0.5 ng/mg creatinine before collar placement). Therefore, there was little evidence that the use of this flea collar contributed to enhanced CP exposure of either children or adults.

  9. Predictors of morbidity and mortality in organophosphorus poisoning: A case study in rural hospital in Karnataka, India

    Directory of Open Access Journals (Sweden)

    Tanveer Hassan Banday

    2015-01-01

    Full Text Available Background: Organophosphorus (OP pesticides poisoning can result from occupational, accidental or intentional exposure. Clinical manifestations include cholinergic syndromes, central nervous (CNS system and cardiovascular disorders. Death is usually due to cardiovascular and respiratory failure. Aim: To evaluate various parameters that can predict outcome of patients in OP poisoning. Materials and Methods: A prospective study conducted in Department of Medicine, Adichunchingiri Institute Of medical Sciences and Research Centre, Karnataka, over period of 1 year. Diagnosis of OP poisoning was based on clinical history of exposure to OP compound and low serum pseudocholinesterase levels. Results: In the present study 133 patients were enrolled, out of which 98.5% were suicidal cases and only 1.5% had accidental exposure. Majority of cases were young male, with F/M ratio 1:3.2. Mortality rates were higher in younger people and in patients who required prolonged ventilator support. The mortality rate was directly proportional to amount of poison consumed, lag time, organ failure (Acute Renal Failure and plasma pseudocholinesterase levels. Acute complications were frequently noted and were related to morbidity and mortality. No strict relationship was found between liver dysfunction, electrolyte disturbance and clinical outcome. Conclusion: This case study concluded that mortality is directly proportionate to the lag time, amount of OP substances consumed, clinical severity, pseudocholinesterase levels, Acute renal failure and duration of ventilatory support. This study highlights the importance of rapid diagnosis, and initiation of early and effective treatment, which may result in less number complications and also decreases the mortality rates.

  10. Transformation of the insecticide teflubenzuron by microorganisms

    NARCIS (Netherlands)

    Finkelstein, Z.I.; Baskunov, B.P.; Rietjens, I.M.C.M.; Boersma, M.G.; Vervoort, J.; Golovleva, L.A.

    2001-01-01

    Transformation of teflubenzuron, the active component in the insecticide commercialized as Nomolt, by soil microorganisms was studied. It was shown that microorganisms, belonging to Bacillus, Alcaligenes, Pseudomonas and Acinetobacter genera are capable to perform the hydrolytic cleavage of the phen

  11. Fitness costs associated with insecticide resistance.

    Science.gov (United States)

    Kliot, Adi; Ghanim, Murad

    2012-11-01

    Insects are exposed to a variety of stress factors in their environment, and, in many cases for insect pests to agriculture, those factors include toxic chemical insecticides. Coping with the toxicity of insecticides can be costly and requires energy and resource allocation for adaptation and survival. Several behavioural, physiological and genetic mechanisms are used by insects to handle toxic insecticides, sometimes leading to resistance by constitutive overexpression of detoxification enzymes or inducing mutations in the target sites. Such actions are costly and may affect reproduction, impair dispersal ability and have several other effects on the insect's fitness. Fitness costs resulting from resistance to insecticides has been reported in many insects from different orders, and several examples are given in this mini-review.

  12. DESCRIPTIVE ANALYSIS OF HOUSEHOLD INSECTICIDE IN COMMUNITY

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    Aram Sih Joharina

    2014-06-01

    Full Text Available The most popular and effective vector control is the use of insecticides. Surveywas done in the houses and some supermarket to know many kind of insecticides usedby people. The formulation, active ingredients, and concentration were recorded andanalyzed. Based on the results of the survey, household insecticides formulated invarious formulations such as liquid, mosquito coils, aerosol, mat and liquid vaporizer,chalk and paper burn. In addition to formulation, active ingredients and concentrationalso vary. Almost all household insecticide products on the market using the syntheticpyrethroid. Selection of household insecticides should be adapted to the type of insectpests because each type of active ingredients and formulations have advantages anddisadvantages. Efficacy of various active ingredients in various formulations has beenstudied and the results vary widely. Insecticide efficacy is influenced by the type ofactive ingredient, dosage, concentration, formulation, and the susceptibility of insectspecies, temperature, sunlight, wind, and application method.Key word: household insecticide, insecticides formulation, active ingredientsABSTRAKPengendalian serangga vektor penyakit yang paling efektif dan populer adalahpenggunaan insektisida. Survei dilakukan di masyarakat dan supermarket untuk mengetahuijcnis-jenis insektisida yang digunakan oleh masyarakat. Berdasarkan hasil survei, insektisidarumah tangga terkemas dalam berbagai formulasi antara lain liquid, mosquito coil, aerosol, mat& liquid vaporizer, kapur serangga dan kertas bakar. Disamping formulasi, bahan aktif dankonsentrasi yang digunakan juga bermacam-macam. Hampir semua produk insektisida rumahtangga di pasaran menggunakan bahan aktif golongan piretroid sintetik. Pemilihan insektisidarumah tangga hendaknya disesuaikan dengan jenis serangga sasaran karena tiap jenis bahan aktifdan formulasi memiliki kelcbihan dan kekurangan. Efikasi berbagai bahan aktif dalam berbagaiformulasi telah

  13. Organophosphorus flame retardants – Toxicity and influence on human health

    Directory of Open Access Journals (Sweden)

    Elżbieta Bruchajzer

    2015-06-01

    Full Text Available Organophosphorus flame retardants (flame retardants, FRs have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs – persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexylphosphate (TEHP, tris(2-butoxyethylphosphate (TBEP, triphenyl phosphate (TPP, tris(2-chloroethylphosphate (TCEP, tetrakis(hydroxymethyl-phosphonium chloride (THPC, tributyl phosphate (TBP, tricresyl phosphate (TCP, tris(2-chloroisopropylphosphate (TCPP, tris(1,3-dichloroisopropylphosphate (TDCP and tetrakis(hydroxymethyl phosphonium sulphate (THPS. In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP. They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs. Med. Pr. 2015;66(2:235–264

  14. Spectroscopic Analysis of Organophosphorus Pesticides Using Colorimetric Reactions

    Institute of Scientific and Technical Information of China (English)

    Amit Kumar Sharma

    2016-01-01

    The UV-Vis and infrared (IR)absorption spectra of organophosphorus (OP)pesticides have been studied.A correlation in spectra was developed to optimize the OP pesticides in the environments.The spec-troscopic (UV-Vis and IR)spectrum of OP pesticides like methyl parathion,malathion and parathion has been interpreted in detail.A complete calculation of the normal frequencies and absolute intensities of UV-Vis and IR absorption bands are interpreted with the help of corresponding experimental data.In the colorimetric reac-tions,the bands appear at 2 077,1 637,1 455,1 015,655 cm-1 for malathion;2 081,1 639,1 316,1 015, 794,683 cm-1 for parathion;2 078,1 632,1 032,794 cm-1 for methyl parathion were used for quantitative or qualitative analysis.All these IR spectra were acquired by averaging 100 scans at a resolution of 4 cm-1 .It is determined experimentally in the region 200~450 nm for UV-Vis absorption bands and in the region 400~4 000 cm-1 for IR absorption bands.It is concluded that the mainly optically active groups (P—OH, C—O, P—O, C—O—C,P—O—C, P—S, —OH)present in pesticides which are responsible in change in sig-nificant data for quantitative and qualitative analysis.The various optical properties like wavelength,band en-ergy,wave number,and frequency,also are calculated.

  15. [ORGANOPHOSPHORUS FLAME RETARDANTS - TOXICITY AND INFLUENCE ON HUMAN HEALTH].

    Science.gov (United States)

    Bruchajzer, Elżbieta; Frydrych, Barbara; Szymańska, Jadwiga Anna

    2015-01-01

    Organophosphorus flame retardants (flame retardants, FRs) have been used for several decades in many industries, including the production of dyes, varnishes, adhesives, synthetic resins, polyvinyl chloride, hydraulic fluids, plastics and textiles. Their importance in recent times has increased due to i.a., significantly reduced use of polybrominated diphenyl ethers (PBDEs) - persistent organic pollutants, dangerous for the environment. The aim of this study was to review the available literature data concerning phosphorous FRs primarily for neurotoxic, fertility, reproductive and carcinogenic effects. The analysis concerned the following most commonly used substances: tris(2-ethylhexyl)phosphate (TEHP), tris(2-butoxyethyl)phosphate (TBEP), triphenyl phosphate (TPP), tris(2-chloroethyl)phosphate (TCEP), tetrakis(hydroxymethyl)-phosphonium chloride (THPC), tributyl phosphate (TBP), tricresyl phosphate (TCP), tris(2-chloroisopropyl)phosphate (TCPP), tris(1,3-dichloroisopropyl)phosphate (TDCP) and tetrakis(hydroxymethyl)phosphonium sulphate (THPS). In animal studies neurotoxic effects were found after exposure to TBEP, THPC, TBP and TCP, while in humans they were observed only after exposure to TCP. TCEP, THPS, TBP, TCP and TDCP caused disorders in fertility and/or fetal development of animals. Adverse effects on reproduction in humans may be caused by TPP, TCP, and TDCP. In laboratory animals the development of tumors was observed after high doses of TEHP, TCEP, TBP and TDCP. None of these compounds is classified as a human carcinogen. The environmental toxicity of phosphate FRs is low (except for TPP, TCEP and TBEP). They are not stable compounds, in living organisms they are metabolised and quickly excreted. Therefore, they can be used as an alternative to PBDEs.

  16. Effect of Intensive Atropine Doses (Rapid Incremental Loading and Titration for Management of Organophosphorus Pesticide Poisoning: a Case Series

    Directory of Open Access Journals (Sweden)

    Abu Saleh Ahmed

    2014-03-01

    Full Text Available Background:Acute poisoning with organophosphorus (OP pesticides is a common method of suicide and entails considerable mortality in Bangladesh. The objective of this study was to evaluate the effects and outcomes of a protocol for treatment of OP poisoning that included titrated incremental atropine as loading dose and slow infusion for maintenance.  Methods:In this prospective descriptive case series, definitive OP poisoned patients were enrolled in an adult medicine unit of Dhaka Medical College Hospital from April 2006 to April 2007. Clinical examinations were done as soon as the patient entered the ward. Patient’s demographics, comorbid conditions and the occurrence of specific clinical outcomes including death, need for assisted ventilation and clinical complications were recorded. The patients were treated according to the protocol. Results: A total of 56 patients were enrolled over the study period. The median age of the study population was 22.5 years. Most patients were men (67.8%. The most common clinical presentation was miosis (58.9%. In total, 11 patients died (19.6%. Intermediate syndrome developed in 12 patients (21.4% and 6 of them died. Assisted ventilation was required in 16 cases (28.5. Patients with diastolic blood pressure ≤ 70 mmHg and/or GCS ≤ 10 were significantly less likely to survive (P = 0.02, 0.006, respectively. Moreover, early respiratory failure (P < 0.001 and the need for assisted ventilation (P < 0.001 were significantly higher among deceased cases. The mortality rate in this study was similar to previous studies. The frequency of atropine toxicity in the present study (1.8% was considerably lower than conventional regimen used in previous studies. Conclusion:Using the new protocol, lower rate of atropine toxicity developed in victims. Hence, the new protocol appears to be safer and its effectiveness should be further evaluated in case control studies in Bangladesh.    How to cite this article: Ahmed AS

  17. 肿瘤坏死因子α-238 G/A 基因多态性与有机磷中毒中间综合征的关系%Relationship between tumor necrosis factor α-238G/A gene polymorphism and the intermediate syndrome of organophosphorus poisoning

    Institute of Scientific and Technical Information of China (English)

    陆启峰; 梁烨; 李天资; 李近都; 黄元东

    2014-01-01

    目的:探讨肿瘤坏死因子α( TNFα)基因-238位点基因单核苷酸多态性( SNP)与有机磷中毒中间综合征的关联性。方法对36例有机磷中毒中间综合征(实验组)患者运用多聚酶链反应技术检测TNFα基因-238位点的SNP。并与67例急性重度有机磷中毒(对照组)比较。结果实验组TNFα-238G/G、G/A、A/A表型频率分别为0.778、0.104、0.028;对照组分别为0.940、0.060、0.000。实验组TNFα-238G、TNFα-238A基因频率分别为0.875、0.125;对照组分别为0.970、0.030。 TNFα-238G/A各种基因型频率在实验组与对照组之间比较差异有统计学意义(P<0.05)。结论 TNFα-238G/A基因多态性与有机磷中毒中间综合征有关联性。%Objective To investigate the tumor necrosis factor α( TNFα) gene -238 loci gene single nucleotide polymorphisms ( SNPs ) and the relevance to intermediate syndrome of organophosphorus poisoning . Methods Thirty -six patients with intermediate syndrome of organophosphorus poisoning were detected the TNFαgene -238 SNPs by polymerase chain reaction technology .The data of TNFαSNPs were analyzed between intermediate syndrome of organophosphorus poisoning and acute severe organophosphorus poisoning ( control ) .Results Intermediate syndrome of organophosphorus poisoning group of TNFα-238G/G, G/A and A/A phenotypic frequency were 0.778, 0.104 and 0.028, respectively;the acute severe organophosphate poisoning were 0.940, 0.060 and 0.000 , respectively .Intermediate syndrome of organophosphorus poisoning group of TNFα-238 G, TNFα-238A gene frequency were 0.875, 0.125; the acute severe organophosphate poisoning were 0.970 and 0.030.TNFαgene-238G/A variety of genotype frequencies between intermediate syndrome of organophosphorus poisoning group and acute severe organophosphate poisoning the difference was statistically significant (P<0.05).Conclusion TNFαgene-238G/A polymorphism has correlation

  18. Comparative Toxicological Study between Exposed and Non-Exposed Farmers to Organophosphorus Pesticides

    Directory of Open Access Journals (Sweden)

    Fariba Taghavian

    2016-04-01

    Full Text Available Objective: The purpose of this work was to compare DNA damage, acetylcholinesterase (AChE activity, inflammatory markers and clinical symptoms in farmers exposed to organophosphorus pesticides to individuals that had no pesticide exposure. Materials and Methods: We conducted a cross-sectional survey with a total of 134 people. The subject group consisted of 67 farmers who were exposed to organophosphorus pesticides. The control group consisted of 67 people without any contact with pesticides matched with the subject group in terms of age, gender, and didactics. Oxidative DNA damage, the activities of AChE, interleukin-6 (IL6, IL10 and C-reactive protein (CRP in serum were measured and clinical examinations conducted in order to register all clinical signs. Results: Compared with the control group, substantial gains were observed in the farmers’ levels of oxidative DNA damage, IL10 and CRP. There was significantly less AChE activity in farmers exposed to organophosphorus pesticides. The levels of IL6 in both groups did not significantly differ. Conclusion: The outcomes show that exposure to organophosphorus pesticides may cause DNA oxidative damage, inhibit AChE activity and increase the serum levels of inflammatory markers. Using biological materials instead of chemical pesticides and encouraging the use of safety equipment by farmers are some solutions to the adverse effects of exposure to organophosphorous pesticides.

  19. RESEARCH OF HEAVY METALS, ORGANOCHLORINE AND ORGANOPHOSPHORUS PESTICIDES IN POWDERED INFANT FORMULA

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    M.C. Abete

    2009-02-01

    Full Text Available During the period between october 2007 and november 2008 were collected 60 samples of powdered infant formula. The analysis for the detection of heavy metals, organochlorine and organophosphorus pesticides show that the environmental situation is under control and powdered infant formula satisfies this health requisite.

  20. Assessing the Developmental Neurotoxicity of 27 Organophosphorus Pesticides Using a Zebrafish Behavioral Assay

    Science.gov (United States)

    Assessing the Developmental Neurotoxicity of 27 Organophosphorus Pesticides Using a Zebrafish Behavioral Assay, Waalkes, M., Hunter, D.L., Jarema, K., Mundy, W., and S. Padilla. The U.S. Environmental Protection Agency is evaluating methods to screen and prioritize organophosphor...

  1. Mineralisation and primary biodegradation of aromatic organophosphorus flame retardants in activated sludge

    NARCIS (Netherlands)

    Jurgens, S.S.; Helmus, R.; Waaijers, S.L.; Uittenbogaard, D.; Dunnebier, D; Vleugel, M; Kraak, M.H.S.; de Voogt, P.; Parsons, J.R.

    2014-01-01

    Halogen-free flame retardants (HFFRs), such as the aromatic organophosphorus flame retardants (OPFRs) triphenyl phosphate (TPHP), resorcinol bis(diphenylphosphate) (PBDPP) and bisphenol A bis(diphenylphosphate) (BPA-BDPP) have been proposed as potential replacements for brominated flame retardants i

  2. Comparative Toxicological Study between Exposed and Non-Exposed Farmers to Organophosphorus Pesticides

    Science.gov (United States)

    Taghavian, Fariba; Vaezi, Gholamhassan; Abdollahi, Mohammad; Malekirad, Ali Akbar

    2016-01-01

    Objective The purpose of this work was to compare DNA damage, acetylcholinesterase (AChE) activity, inflammatory markers and clinical symptoms in farmers exposed to organophosphorus pesticides to individuals that had no pesticide exposure. Materials and Methods We conducted a cross-sectional survey with a total of 134 people. The subject group consisted of 67 farmers who were exposed to organophosphorus pesticides. The control group consisted of 67 people without any contact with pesticides matched with the subject group in terms of age, gender, and didactics. Oxidative DNA damage, the activities of AChE, interleukin-6 (IL6), IL10 and C-reactive protein (CRP) in serum were measured and clinical examinations conducted in order to register all clinical signs. Results Compared with the control group, substantial gains were observed in the farmers’ levels of oxidative DNA damage, IL10 and CRP. There was significantly less AChE activity in farmers exposed to organophosphorus pesticides. The levels of IL6 in both groups did not significantly differ. Conclusion The outcomes show that exposure to organophosphorus pesticides may cause DNA oxidative damage, inhibit AChE activity and increase the serum levels of inflammatory markers. Using biological materials instead of chemical pesticides and encouraging the use of safety equipment by farmers are some solutions to the adverse effects of exposure to organophosphorous pesticides. PMID:27054123

  3. Determination of organophosphorus acids by thermo-spray liquid chromatography-mass spectrometry

    NARCIS (Netherlands)

    Wils, E.R.J.; Hulst, A.G.

    1988-01-01

    The determination of thirteen organophosphorus acids, hydrolysis products of nerve agents and pesticides, by a combination of ion-pair liquid chromatography on a reversed-phase C18 column and thermospray mass spectrometry was investigated. Ammonium acetate and three tetraalkylammonium salts with dif

  4. 40 CFR 798.6560 - Subchronic delayed neuro-toxicity of organophosphorus substances.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Subchronic delayed neuro-toxicity of organophosphorus substances. 798.6560 Section 798.6560 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... gelatine capsules. (7) Study conduct—(i) General. Healthy young adult hens free from interfering...

  5. To identify morbidity and mortality predictors in acute organophosphate poisoning

    Directory of Open Access Journals (Sweden)

    Arti Muley

    2014-01-01

    Full Text Available Background: Organophosphorus poisoning remains an important cause of morbidity and mortality, but no definite parameters have been identified as predictors of outcome. Prediction of morbidity at presentation might help in decision making in places of limited resources like rural settings in developing countries. Materials and Methods: A total of 76 cases were included in this retrospective cohort study. Logged relative risk of requirement of mechanical ventilation and hospital stay >7 days was measured in patients with serum acetylcholinesterase (s. acetylcholinesterase 1000, presenting in 12 and in patients with SpO 2 7 days. Conclusion: S. acetylcholinesterase, SpO 2 at room air, GCS, and duration of exposure at presentation can be used to identify the requirement of special care in acute organophosphorus poisoning. This can aid in decision making regarding admission to intensive care unit and referral in the places with limited resources.

  6. Analysis on the Feasibility of Drosophila melanogaster as An Indcator Insect to Detect Insecticide Residue Rapidly in Vegetables%黑腹果蝇作为指示昆虫快速检测蔬菜中农药残留可行性分析

    Institute of Scientific and Technical Information of China (English)

    孙丽娟; 任士伟; 邢小霞; 徐丽娟; 董向丽

    2011-01-01

    The toxicity of organophosphorus, carbamate, neonicotinoid, pyrethroid insecticides to Drosophila melanogaster were determined using the method of feeding on toxic medium. The result showed that the tested D. Melanogasterwere very sensitive to pyrethroid and organophosphorus insecticides. After 3h treatment, the LC50 were less than or near to maximum residue limit ( MRL). However, the D. Melanogaster was less sensitive to carbamate and neonicotinoid insecticides. The sensibility of D. Melanogaster to pyrethroid and organophosphorus pesticides mixed in the homogenate of vegetable were future determined, and the same result was obtained. After 3h treatment, the LC50 of DDVP, Chlorpyrifos and Cyfluthrin were 0. 123mg/kg, 0. 912mg/kg and 0. 021mg/kg respectively , which were lower than the MRL ( GB ). This experiment indicated that the tested insect D. Melanogaster should be feasible to be used as an indicator to detect pyrethroid and organophosphorus insecticides residues rapidly in vegetables.%采用培养基混毒法,测定了黑腹果蝇(Drosophila melanogaster)对有机磷、氨基甲酸酯、新烟碱类和拟除虫菊酯类杀虫剂的敏感性.结果显示,所试黑腹果蝇对拟除虫菊酯类、有机磷类杀虫剂非常敏感,3h内LC50低于或接近于最大残留限量(MRL);对氨基甲酸酯类杀虫剂敏感性稍差,对新烟碱类杀虫剂不敏感.进一步测定黑腹果蝇对蔬菜匀浆中有机磷类和拟除虫菊酯类杀虫剂的敏感性,结果与培养基混毒法一致,黑腹果蝇保持了对这两类杀虫剂的高度敏感性,3h内敌敌畏、毒死蜱和氯氟氰菊酯的LC50分别是0.123mg/kg、0.912mg/kg和0.021 mg/kg,均低于中国国家标准的最大残留限量.所试黑腹果蝇可以作为指示昆虫用于蔬菜中有机磷类和拟除虫菊酯类杀虫剂残留的快速检测.

  7. Carbofuran-Induced Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Rizos E

    2004-01-01

    Full Text Available CONTEXT: Carbamate insecticides are widely used in commercial agriculture and home gardening. A serious side effect of organophosphate and carbamate intoxication is the development of acute pancreatitis. CASE REPORT: A 36-year-old Caucasian woman was admitted to our hospital with cholinergic crisis and pancreatitis soon after the ingestion of a carbamate insecticide (carbofuran. An abdominal CT scan disclosed pancreatic necrosis with intrapancreatic fluid collection, consistent with the development of a pancreatic pseudocyst in a subsequent CT scan. No predisposing factor for pancreatitis was evident. Pseudocholinesterase levels returned to normal 7 days later and the patient was discharged in good physical condition one month after admission. DISCUSSION: Although acute pancreatitis is not infrequent after organophosphate intoxication, it is quite rare after carbamate ingestion and has not been previously reported after carbofuran intoxication.

  8. Carboxylic Esterase and Its Associations With Long-term Effects of Organophosphorus Pesticides

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To examine a) the effect of organophosphorus pesticide exposure on activity of carboxylic esterases, namely butyrylcholinesterase (BChE), carboxylesterase (CarbE) and paraoxonase (PonE); and b) the association of polymorphisms of BChE and PonE with individual genetic susceptibility to organophosphorus pesticide exposure. Methods A cross-sectional study was conducted in 75 workers exposed to organophosphorus pesticides and 100 non-exposed controls. The serum activity of these enzymes was measured. Variant forms of BCHE-K, PON-192, and PON-55 were detected. A symptom score was developed as a proxy measure of clinical outcomes. Results Activities of both BChE and CarbE were lower in exposed exposed workers with BCHE-K genotype UU (61 cases), genotype UK (12 cases) and genotype KK (2 cases) was 105.05, 84.42 activity in the exposed workers with PON-192 genotype BB (37), genotype AB (27) and genotype AA (11) was 116.8, 91.2, and 9.20. The symptom score was the highest in individuals with abnormal homozygote for each of the three gene loci. Conclusions Long-term exposure to organophosphorus pesticides can inhibit BChE and CarbE activity, but exerts no inhibitory effect on PonE activity. Different genotypes of BCHE-K, PON-192, and PON-55 may be related to the severity of adverse health effects of organophosphorus pesticide exposure. Implications of potentially higher susceptibility of workers with mutant homozygotes should be evaluated to reduce health risks.

  9. Using the Chiral Organophosphorus Derivatizing Agents for Determination of the Enantiomeric Composition of Chiral Carboxylic Acids by 31PNMR Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Chao CHE; Zhong Ning ZHANG; Gui Lan HUANG; Xin Xing WANG; Zhao Hai QIN

    2004-01-01

    The use of chiral organophosphorus derivatizing agents prepared in situ from chiral tartrate or chiral diamine for the 31PNMR determination of the enantiomeric composition of chiral carboxylic acids is described. The method is accurate, reliable and convenient.

  10. Organophosphorus Compound DEPBT as a Coupling Reagent for Oligopeptides and Peptoids Synthesis:Studies on Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    HuiLIU; YunHuaYE; 等

    2002-01-01

    Some oligopeptides and peptoids were synthesized by applying the organophosphorus compound DEPBT as a coupling reagent. D-Biotin-OOBt was obtained unexpectedly. A proposed reaction mechanism for DEPBT-mediated coupling was proved.

  11. Conformational Variability of Organophosphorus Hydrolase upon Soman and Paraoxon Binding

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Diego Eb; Lins, Roberto D.; Pascutti, Pedro G.; Lei, Chenghong; Soares, Thereza A.

    2011-12-31

    The bacterial enzyme organophosphorus hydrolase (OPH) exhibits both catalytic and substrate promiscuity. It hydrolyzes bonds in a variety of phosphotriester (P-O), phosphonothioate (P-S), phosphofluoridate (P-F) and phosphonocyanate (F-CN) compounds. However, its catalytic efficiency varies markedly for different substrates, limiting the broad-range application of OPH as catalyst in the bioremediation of pesticides and chemical war agents. In the present study, pK{sub a} calculations and multiple explicit-solvent molecular dynamics (MD) simulations were performed to characterize and contrast the structural dynamics of OPH bound to two substrates hydrolyzed with very distinct catalytic efficiencies: the nerve agent soman (O-pinacolyl-methyl-phosphonofluoridate) and the pesticide paraoxon (diethyl p-nitrophenyl phosphate). pK{sub a} calculations for the substrate-bound and unbound enzyme showed a significant pK{sub a} shift from standard values ({Delta}pK{sub a} = {+-} 3 units) for residues 254His and 275Arg. MD simulations of the doubly protonated 254His revealed a dynamic hydrogen bond network connecting the catalytic residue 301Asp via 254His to 232Asp, 233Asp, 275Arg and 235Asp, and is consistent with a previously postulated proton relay mechanism to ferry protons away from the active site with substrates that do not require activation of the leaving group. Hydrogen bonds between 301Asp and 254His were persistent in the OPH-paraoxon complex but not in the OPH-soman one, suggesting a potential role for such interaction in the more efficient hydrolysis of paraoxon over soman by OPH. These results are in line with previous mutational studies of residue 254His, which led to an increase of the catalytic efficiency of OPH over soman yet decreased its efficiency for paraoxon. In addition, comparative analysis of the molecular trajectories for OPH bound to soman and paraoxon suggests that binding of the latter facilitates the conformational transition of OPH from the

  12. Covalent binding of the organophosphorus agent FP-biotin to tyrosine in eight proteins that have no active site serine

    OpenAIRE

    Grigoryan, Hasmik; Li, Bin; Anderson, Erica K.; Xue, Weihua; Nachon, Florian; Lockridge, Oksana; Schopfer, Lawrence M.

    2009-01-01

    Organophosphorus esters (OP) are known to bind covalently to the active site serine of enzymes in the serine hydrolase family. It was a surprise to find that proteins with no active site serine are also covalently modified by OP. The binding site in albumin, transferrin, and tubulin was identified as tyrosine. The goal of the present work was to determine whether binding to tyrosine is a general phenomenon. Fourteen proteins were treated with a biotin-tagged organophosphorus agent called FP-b...

  13. Cytochromes P450 and insecticide resistance.

    Science.gov (United States)

    Scott, J G

    1999-09-01

    The cytochrome P450-dependent monooxygenases (monooxygenases) are an extremely important metabolic system involved in the catabolism and anabolism of xenobiotics and endogenous compounds. Monooxygenase-mediated metabolism is a common mechanism by which insects become resistant to insecticides as evidenced by the numerous insect species and insecticides affected. This review begins by presenting background information about P450s, the role of monooxygenases in insects, and the different techniques that have been used to isolate individual insect P450s. Next, insecticide resistance is briefly described, and then historical information about monooxygenase-mediated insecticide resistance is reviewed. For any case of monooxygenase-mediated resistance, identification of the P450(s) involved, out of the dozens that are present in an insect, has proven very challenging. Therefore, the next section of the review focuses on the minimal criteria for establishing that a P450 is involved in resistance. This is followed by a comprehensive examination of the literature concerning the individual P450s that have been isolated from insecticide resistant strains. In each case, the history of the strain and the evidence for monooxygenase-mediated resistance are reviewed. The isolation and characterization of the P450(s) from the strain are then described, and the evidence of whether or not the isolated P450(s) is involved in resistance is summarized. The remainder of the review summarizes our current knowledge of the molecular basis of monooxygenase-mediated resistance and the implications for the future. The importance of these studies for development of effective insecticide resistance management strategies is discussed.

  14. Glutathione S-transferase conjugation of organophosphorus pesticides yields S-phospho-, S-aryl-, and S-alkylglutathione derivatives.

    Science.gov (United States)

    Fujioka, Kazutoshi; Casida, John E

    2007-08-01

    Pesticide detoxification is a central feature of selective toxicity and safety evaluation. Two of the principal enzymes involved are GSH S-transferases (GSTs) and cytochrome P450s acting alone and together. More than 100 pesticides are organophosphorus (OP) compounds, but with few exceptions, their GSH conjugates have not been directly observed in vitro or in vivo. The major insecticides chlorpyrifos (CP) and diazinon are of particular interest as multifunctional substrates with diverse metabolites, while ClP(S)(OEt) 2 and the cotton defoliant tribufos are possible precursors of phosphorylated GSH conjugates. Formation of GSH conjugates by GST with GSH was studied in vitro with and without metabolic activation by human liver microsomes or P450 3A4 with NADPH. Metabolites were analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). Five GSH conjugates were identified from CP and chlorpyrifos oxon (CPO), i.e., GSCP and GSCPO in which the 6-chloro substituent of CP and CPO, respectively, is displaced by GSH; S-(3,5,6-trichloropyridin-2-yl)glutathione; S-(3,5-dichloro-6-hydroxypyridin-2-yl)glutathione; and S-ethylglutathione. GST of a human liver microsomal preparation but not P450 3A4 with GSH metabolized CP to GSCP. With GST and GSH, diazinon and diazoxon gave S-(2-isopropyl-4-methylpyrimidin-6-yl)glutathione and ClP(S)(OEt) 2 yielded GSP(S)(OEt) 2. With microsomes, NADPH, GST, and GSH tribufos gave GSP(O)(SBu) 2. The liver of intraperitoneally treated mice contained GSCP from CP, GSP(S)(OEt) 2 from ClP(S)(OEt) 2, and GSP(O)(SBu) 2 from tribufos. GSP(S)(OEt) 2 and GSP(O)(SBu) 2 are the first S-phosphoglutathione metabolites observed in vitro and in vivo directly by LC-ESI-MS. Nine other OP pesticides gave only O-dealkylation in the GST/GSH system. GST-catalyzed metabolism joins P450s and hydrolases as important contributors to OP detoxification.

  15. Alteration of leaf metabolism in Bt-transgenic rice (Oryza sativa L.) and its wild type under insecticide stress.

    Science.gov (United States)

    Zhou, Jia; Zhang, Lei; Chang, Yuwei; Lu, Xin; Zhu, Zhen; Xu, Guowang

    2012-08-03

    Insecticide is always used to control the damage from pests, while the potential influence on plants is rarely known. Time-course metabolic changes of wild and Bacillus thuringiensis (Bt) transgenic rice (Oryza sativa L.) plants after insecticide treatment were investigated by using gas chromatography-mass spectrometry (GC-MS). A combined statistical strategy of 2-way ANOVA and multivariate analyses (principal component analysis and hierarchal cluster analysis) was performed to find the stress-associated effects. The results reveal that a wide range of metabolites were dynamically varied in both varieties as a response to insecticide, in multiple metabolic pathways, such as biosynthesis and metabolism of amino acids, carbohydrates, fatty acids, TCA cycle, and the shikimate/phenylpropanoid pathway, and most of the changes were correlated with the exposure time and dependent on the variety. A set of stress defenses were activated, including phytohormone signaling pathway, antioxidant defense system, shikimate-mediated secondary metabolism, and so on. In particular, insecticide led to much stronger regulations of signaling molecules (salicylate and the precursor of jasmonate) and antioxidants (α-tocopherol and dehydroascorbate/ascorbate) in Bt-transgenic variety at the early stage. Our results demonstrated that the Bt-transgenic rice had a more acute and drastic response to insecticide stress than its non-transgenic counterpart in antioxidant system and signaling regulation.

  16. Cholinesterase Activity in Health Workers Involved in Handling and Spraying of Organophosphorous Insecticides

    Directory of Open Access Journals (Sweden)

    Himanshu Madaan

    2011-04-01

    Full Text Available Background: Recent era of agricultural boon is partially the result of extensive use of insecticides and pesticides. But these compounds also have potential to significantly alter the ecosystem and can cause acute poisonings as well as long term detrimental health effects in humans. These compounds can cause toxicity through all routes of exposure. They exert their effect mainly by the inhibition of Acetylcholinesterase (AC hE, which functions by removing acetylcholine (AC h from its postsynaptic receptors. Aims and Objectives: Human exposure to Organophosphorous (OP pesticides can develop lowered cholinesterase levels. The aim of the present study was to estimate the plasma levels of AC hE in personnel involved in handling of these compounds, during the period of active spraying operations. Methodology: The present study was conducted on 38 subjects working as Multipurpose Health Workers (MPHW GROUP-1 and Field Workers (FW GROUP-2 involved in the actual spraying of the insecticides, in District Rohtak, Haryana, India to see the effect of exposure to OP insecticides. Plasma cholinesterase activity was measured by a kinetic method based on hydrolysis of butrylthiocholine. The data was statistically analyzed using SPSS statistical package (SPSS version 5.0. Results and interpretation: The mean cholinesterase activity in group-2 was lower by 27.76% than that in group-1 and this difference was statistically significant (p < 0.05. The workers involved in actual spraying of the insecticides had a more marked reduction in the levels of Plasma AC hE, compared to the workers involved only in the handling of the insecticides indicating that this group is at a bigger risk.

  17. Photocatalytic degradation of an organophosphorus pesticide from agricultural waste by immobilized TiO2 under solar radiation

    Directory of Open Access Journals (Sweden)

    Marcia Regina Assalin

    2016-11-01

    Full Text Available This paper describes solar heterogeneous photocatalysis using immobilized TiO2 applied in the treatment of agricultural waste resulting from the application of commercial formulations of methyl parathion. The disappearance of the insecticide, as well as the formation of its metabolite, was monitored by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS, while mineralization efficiency was monitored by measurements of total organic carbon (TOC. Toxicity studies were performed using the microcrustacean Artemia salina. The TOC removal efficiency by photocatalytic process was 48.5%. After 45 minutes of treatment, the removal efficiency of methyl parathion was 90%, being completely mineralized at the end of treatment. The formation and removal of the metabolite methyl paraoxon was observed during the photocatalytic process. The photocatalytic treatment resulted in increased microcrustacean mobility, indicating a reduction of acute toxicity.

  18. Insecticide Resistance: Challenge to Pest Management and Basic Research

    Science.gov (United States)

    Brattsten, L. B.; Holyoke, C. W.; Leeper, J. R.; Raffa, K. F.

    1986-03-01

    The agricultural use of synthetic insecticides usually protects crops but imposes strong selection pressures that can result in the development of resistance. The most important resistance mechanisms are enhancement of the capacity to metabolically detoxify insecticides and alterations in target sites that prevent insecticides from binding to them. Insect control methods must incorporate strategies to minimize resistance development and preserve the utility of the insecticides. The most promising approach, integrated pest management, includes the use of chemical insecticides in combination with improved cultural and biologically based techniques.

  19. Fungicide and insecticide residues in rice grains

    Directory of Open Access Journals (Sweden)

    Gustavo Mack Teló

    2017-01-01

    Full Text Available The objective of this study was to analyse residues of fungicides and insecticides in rice grains that were subjected to different forms of processing. Field work was conducted during three crop seasons, and fungicides and insecticides were applied at different crop growth stages on the aerial portion of the rice plants. Azoxystrobin, difenoconazole, propiconazole, tebuconazole, and trifloxystrobin fungicides were sprayed only once at the R2 growth stage or twice at the R2 and R4 growth stages; cypermethrin, lambda-cyhalothrin, permethrin, and thiamethoxam insecticides were sprayed at the R2 growth stage; and permethrin was sprayed at 5-day intervals from the R4 growth stage up to one day prior to harvest. Pesticide residues were analysed in uncooked, cooked, parboiled, polished and brown rice grains as well as rice hulls during the three crop seasons, for a total of 1458 samples. The samples were analysed by gas chromatography with electron capture detection (GC-ECD using modified QuEChERS as the extraction method. No fungicide or insecticide residues were detected in rice grain samples; however, azoxystrobin and cypermethrin residues were detected in rice hull samples.

  20. Insecticide resistance selection in rice planthoppers

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Brown planthopper (BPH, Nilaparvata lugens Stal) and white backed planthopper (WBPH, Sogatella furcifera Horvath) are the main insects on rice in China. The insecticide resistance of the two planthoppers have often been reported. Availability of the resistant population is a prerequisite for studying the resistance mechanism. In this paper, one method to select methamidophos resistance of the two planthoppers was recommended.

  1. The 1975 Insecticide, Herbicide, Fungicide Quick Guide.

    Science.gov (United States)

    Page, Bill G.; Thomson, W. T.

    This is a quick guide for choosing a chemical to use to control a certain pest on a specific crop. Information in the book was obtained from manufacturers' labels and from the USDA and FDA pesticide summary. The book is divided into four parts: (1) insecticides, (2) herbicides, (3) fungicides, and (4) conversion tables. Each of the first three…

  2. ASSESSMENT OF SEVERITY, TREATMENT AND OUTCOME OF ORGANOPHOSPHORUS POISONING: A DESCRIPTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Chandra Indira

    2015-05-01

    Full Text Available BACKGROUND : Organophophorous poisoning constitutes one of the most frequent poisoning in clinical practice all over the country and especially in this area where agriculture is the chief economic occupation. Acute organophophorous poisoning ranks foremost in the list of agents which causes acute pesticide poisoning in the developing countries. Acute poisoning, accidental or due to deliberate ingestion or inhalation of these organophosphate chemicals is an important and one of the most common medical emergencies. Hence the present stud y is undertaken to assess severity of poisoning, management and outcome of organophosphorous poisoning cases admitted in Government General Hospital, Kakinada, A. P. AIMS/OBJECTIVES: 1. Assessment of severity of Organophosphorous poisoning according to Dri esbach’s criteria 2. To study the morbidity and mortality in these patients. MATERIALS AND METHOD S: In this descriptive study fifty patients with organophosphorous insecticide poisoning were evaluated by clinical examination. They were investigated, treate d and their treatment outcome were analyzed. RESULTS: 1. Chlorpyriphos and monocrotophos(together 66% were the most commonly used pesticides. 2. 82% cases reached the hospital within 6 hours for commencement of treatment and were mostly of moderate to se vere degree of OP poisoning while mild cases of accidental poisoning reached after 12 hours. Hence the mortality is high in the former group only. 3. When the severity of poisoning was graded by applying Dreisbach's criteria at the time of admission 34% ha d severe degree of poisoning, 26% had moderate poisoning while 40% of cases presented with mild degree of poisoning. (Most of the cases were accidental inhalation and skin contact exposure. 4. Among the patients belonging to moderate to severe degree of p oisoning 30% of patients were put on assisted mechanical ventilation, indications being uncontrolled pulmonary secretions, continuing hypoxia, not

  3. Insecticide-induced hormesis and arthropod pest management.

    Science.gov (United States)

    Guedes, Raul Narciso C; Cutler, G Christopher

    2014-05-01

    Ecological backlashes such as insecticide resistance, resurgence and secondary pest outbreaks are frequent problems associated with insecticide use against arthropod pest species. The last two have been particularly important in sparking interest in the phenomenon of insecticide-induced hormesis within entomology and acarology. Hormesis describes a biphasic dose-response relationship that is characterized by a reversal of response between low and high doses of a stressor (e.g. insecticides). Although the concept of insecticide-induced hormesis often does not receive sufficient attention, or has been subject to semantic confusion, it has been reported in many arthropod pest species and natural enemies, and has been linked to pest outbreaks and potential problems with insecticide resistance. The study of hormesis remains largely neglected in entomology and acarology. Here, we examined the concept of insecticide-induced hormesis in arthropods, its functional basis and potential fitness consequences, and its importance in arthropod pest management and other areas.

  4. Oviposition and olfaction responses of Aedes aegypti mosquitoes to insecticides.

    Science.gov (United States)

    Canyon, D V; Muller, R

    2013-12-01

    Insecticide applications are not particularly effective on Aedes aegypti mosquitoes which has been attributed to their 'closet' behaviour, or ability to rest in places that remain unexposed to insecticides. Some researchers have suggested that insecticides repel mosquitoes, which would result in less exposure and increased dispersal. If repellence due to insecticides is a fact, acquiring a vector-borne disease, such as dengue, could legitimately be attributed to local vector control efforts and this would lead to restitution claims. This study thus investigated the effect of insecticide presence on mosquito behaviour indirectly via oviposition and directly via olfactory response. In all experiments, oviposition in each insecticide compared to its water and ethanol controls was not significantly different. This indicates that Ae. aegypti mosquitoes are not affected by insecticide presence and that increased dispersal is unlikely to be caused by vector control spraying.

  5. Development and computational modeling of novel bifunctional organophosphorus extractants for lanthanoid separation

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Masahiro; Matsumoto, Satoshi; Uezu, Kazuya; Nakashio, Fumiyuki [Kyushu Univ., Hakozaki, Fukuoka (Japan). Dept. of Chemical Science and Technology; Yoshizuka, Kazuharu; Inoue, Katsutoshi [Saga Univ., Honjyo, Saga (Japan). Dept. of Applied Chemistry

    1999-08-01

    Novel organophosphorus extractants, which have two functional groups in the molecular structure, have been developed for the separation of lanthanoids using the liquid-liquid extraction technique. The separation efficiency and extractability of the novel extractants were investigated for nine lanthanoids. These bifunctional extractants have an extremely high extractability to all the lanthanoids compared to those of commercially available organophosphorus extractants. Two isomers having an identical chemical formulation show significantly different behaviors in lanthanoid extraction. This means that the extraction and separation abilities are quite sensitive to the structure of the spacer connecting the two functional groups. The authors also discuss the experimental results with a computational modeling by means of molecular mechanics and semiempirical molecular orbital methods. The novel molecular mechanics (MM) calculation program MOMEC enables them to analyze the stable conformation of a series of lanthanoid complexes. The calculation suggests that the structural effect of the spacer is one of the decisive factors for enhancing selectivity and extractability in lanthanoid extraction.

  6. Upconversion nanoparticle-based fluorescence resonance energy transfer assay for organophosphorus pesticides.

    Science.gov (United States)

    Long, Qian; Li, Haitao; Zhang, Youyu; Yao, Shouzhuo

    2015-06-15

    This paper reports a novel nanosensor for organophosphorus pesticides based on the fluorescence resonance energy transfer (FRET) between NaYF4:Yb,Er upconversion nanoparticles (UCNPs) and gold nanoparticles (AuNPs). The detection mechanism is based on the facts that AuNPs quench the fluorescence of UCNPs and organophosphorus pesticides (OPs) inhibit the activity of acetylcholinesterase (AChE) which catalyzes the hydrolysis of acetylthiocholine (ATC) into thiocholine. Under the optimized conditions, the logarithm of the pesticides concentration was proportional to the inhibition efficiency. The detection limits of parathion-methyl, monocrotophos and dimethoate reached 0.67, 23, and 67 ng/L, respectively. Meanwhile, the biosensor shows good sensitivity, stability, and could be successfully applied to detection of OPs in real food samples, suggesting the biosensor has potentially extensive application clinic diagnoses assays.

  7. A screen-printed, amperometric biosensor for the determination of organophosphorus pesticides in water samples

    Institute of Scientific and Technical Information of China (English)

    Junfeng Dou; Fuqiang Fan; Aizhong Ding; Lirong Cheng; Raju Sekar; Hongting Wang; Shuairan Li

    2012-01-01

    An amperometric biosensor based on screen-printed electrodes (SPEs) was developed for the determination of organophosphorus pesticides in water samples.The extent of acetylcholinesterase (AChE) deactivation was determined and quantified for pesticideconcentrations in water samples.An enzyme immobilization adsorption procedure and polyacrylamide gel matrix polymerization were used for fabrication of the biosensor,with minimal losses in enzyme activity.The optimal conditions for enzyme catalytic reaction on the SPEs surfaces were acetylthiocholine chloride (ATChC(1)) concentration of 5 mmol/L,pH 7 and reaction time of 4 min.The detectionlimits for three organophosphorus pesticides (dichlorvos,monocrotophs and parathion) were in the range of 4 to 7 μg/L when an AChE amount of 0.1 U was used for immobilization.

  8. Inhibition of voltage-gated calcium channels after subchronic and repeated exposure of PC12 cells to different classes of insecticides

    NARCIS (Netherlands)

    Meijer, Marieke; Brandsema, Joske A R; Nieuwenhuis, Desirée; Wijnolts, Fiona M J; Dingemans, Milou M L; Westerink, Remco H S

    2015-01-01

    We previously demonstrated that acute inhibition of voltage-gated calcium channels (VGCCs) is a common mode of action for (sub)micromolar concentrations of chemicals, including insecticides. However, since human exposure to chemicals is usually chronic and repeated, we investigated if selected insec

  9. An efficient method for synthesis of organophosphorus compounds in aqueous media

    Institute of Scientific and Technical Information of China (English)

    Reza Heydari; Malek Taher Maghsoodlou; Razieh Nejat Yami

    2009-01-01

    A convenient and facile one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds is reported by the reaction of triphenyiphosphine, dialkylacetylenedicarboxylates and N-H, C-H or S-H acids in the presence of poly-ethyleneglycol (PEG), β-cyclodextrin (β-CD), glycerine (Gly) or ethyleneglycol (EG) in water. This methodology is of interest due to the use of water as a solvent, thus minimizing the cost operational hazards, and environmental pollution.

  10. ORGANOPHOSPHORUS PESTICIDE RESIDUES IN GREEK VIRGIN OLIVE OIL: LEVELS, DIETARY INTAKE AND RISK ASSESSMENT

    OpenAIRE

    Tsoutsi, Charoula; Konstantinou, Ioannis; Hela, Dimitra

    2008-01-01

    Abstract In this study, the occurrence of organophosphorus pesticides (OPs) and metabolite residues was investigated in 167 samples of Greek virgin olive oil during a two-year (2004–2005) sampling campaign. A total of 30.5% of samples contained detectable residues while only one sample contained dimethoate residues higher than the maximum residue limits. Among the seven detected OPs, fenthion and fenthion sulfoxide residues were detected in 10.8% and 14.4% of the samples...

  11. Study on the toxic effect of the mixture of organophosphorus pesticide on perinatal rats

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To observe the toxic effect of the mixture of organophosphorus pesticide (MOP) on maternal rats and on the growth and development of their offspring. Methods Totally 40 Sprague-Dawley pregnant rats were randomly divided into three MOP dose groups and one control to which their offspring would be assigned. The experimental dosage of MOP and distilled water were administered orally starting on gestation day 15 and continued for 35 days. The physical development indices and the learning ability of F1...

  12. The quantum-chemical determination of group contributions to the thermodynamic properties of organophosphorus compounds

    Science.gov (United States)

    Dorofeeva, O. V.; Ryzhova, O. N.; Moiseeva, N. F.

    2008-06-01

    The enthalpies of formation, entropies, and heat capacities of 95 organophosphorus derivatives calculated by nonempirical quantum-chemical methods were used to develop the additive method for estimating the thermodynamic properties of these compounds. 86 group contribution values were obtained for estimating the thermodynamic properties of diverse organic derivatives of phosphorus in the oxidation states 3 and 5 (three-and four-coordinate phosphorus atoms).

  13. Long Alkyl Chain Organophosphorus Coupling Agents for in Situ Surface Functionalization by Reactive Milling

    Directory of Open Access Journals (Sweden)

    Annika Betke

    2014-08-01

    Full Text Available Innovative synthetic approaches should be simple and environmentally friendly. Here, we present the surface modification of inorganic submicrometer particles with long alkyl chain organophosphorus coupling agents without the need of a solvent, which makes the technique environmentally friendly. In addition, it is of great benefit to realize two goals in one step: size reduction and, simultaneously, surface functionalization. A top-down approach for the synthesis of metal oxide particles with in situ surface functionalization is used to modify titania with long alkyl chain organophosphorus coupling agents. A high energy planetary ball mill was used to perform reactive milling using titania as inorganic pigment and long alkyl chain organophosphorus coupling agents like dodecyl and octadecyl phosphonic acid. The final products were characterized by IR, NMR and X-ray fluorescence spectroscopy, thermal and elemental analysis as well as by X-ray powder diffraction and scanning electron microscopy. The process entailed a tribochemical phase transformation from the starting material anatase to a high-pressure modification of titania and the thermodynamically more stable rutile depending on the process parameters. Furthermore, the particles show sizes between 100 nm and 300 nm and a degree of surface coverage up to 0.8 mmol phosphonate per gram.

  14. Integrated microwave processing system for the extraction of organophosphorus pesticides in fresh vegetables.

    Science.gov (United States)

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Xu, Xu; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming

    2015-03-01

    A simple and efficient integrated microwave processing system (IMPS) was firstly assembled and validated for the extraction of organophosphorus pesticides in fresh vegetables. Two processes under microwave irradiation, dynamic microwave-assisted extraction (DMAE) and microwave-accelerated solvent elution (MASE), were integrated for simplifying the pretreatment of the sample. Extraction, separation, enrichment and elution were finished in a simple step. The organophosphorus pesticides were extracted from the fresh vegetables into hexane with DMAE, and then the extract was directly introduced into the enrichment column packed with active carbon fiber (ACF). Subsequently, the organophosphorus pesticides trapped on the ACF were eluted with ethyl acetate under microwave irradiation. No further filtration or cleanup was required before analysis of the eluate by gas chromatography-mass spectrometry. Some experimental parameters affecting extraction efficiency were investigated and optimized, such as microwave output power, kind and volume of extraction solvent, extraction time, amount of sorbent, elution microwave power, kind and volume of elution solvent, elution solvent flow rate. Under the optimized conditions, the recoveries were in the range of 71.5-105.2%, and the relative standard deviations were lower than 11.6%. The experiment results prove that the present method is a simple and effective sample preparation method for the determination of pesticides in solid samples.

  15. Third International Meeting on Esterases Reacting with Organophosphorus Compounds

    Science.gov (United States)

    1998-01-01

    in normal, habituated and transformed tissue lines of sugar beet {Beta vulgais L.). As the results of isoelectric focussing showed, tumour tissue...observed over 2- fold higher AChE levels in cortex for over 80 hours following acute stress. Therefore, these mice resemble transgenic mice...overexpressing brain AChE. However, AChE transgeneic mice suffer delayed cognitive and neuromotor pathologies. Our findings therefore imply a common mechanism

  16. Ternary toxicological interactions of insecticides, herbicides, and a heavy metal on the earthworm Eisenia fetida

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanhua [State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control/Key Laboratory for Pesticide Residue Detection of Ministry of Agriculture, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 (China); Chen, Chen [Key Laboratory of Agro-Product Quality and Safety of Ministry of Agriculture, Institute of Quality Standards and Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Qian, Yongzhong, E-mail: qyzcaas@aliyun.com [Key Laboratory of Agro-Product Quality and Safety of Ministry of Agriculture, Institute of Quality Standards and Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Zhao, Xueping [State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control/Key Laboratory for Pesticide Residue Detection of Ministry of Agriculture, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 (China); Wang, Qiang, E-mail: qiangwang2003@vip.sina.com [State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control/Key Laboratory for Pesticide Residue Detection of Ministry of Agriculture, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 (China)

    2015-03-02

    Highlights: • The combined toxicity of insecticides, herbicides, and a heavy metal was examined. • Acute earthworm toxicity assays were conducted in twenty-one ternary mixtures. • Synergism predominated in the majority of the mixtures at low effect levels. • Combination index method could more accurately predict the combined toxicity. - Abstract: The combined toxicities of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor), and a heavy metal (cadmium) have been examined using the acute toxicity test on the earthworm. With a concentration of 2.75 mg/kg being lethal for 50% of the organisms, imidacloprid exhibited the highest acute toxicity toward the earthworm Eisenia fetida. Toxicological interactions of these chemicals in ternary mixtures were studied using the combination-index (CI) equation method. Twenty-one ternary mixtures exhibited various interactive effects, in which 11 combinations showed synergistic effects, four led to dual synergistic/additive behaviors, one exhibited an additive effect, and five showed increasing antagonism within the entire range of effects. The CI method was compared with the classical models of concentration addition and independent action, and it was found that the CI method could accurately predict combined toxicity of the chemicals studied. The predicted synergism in the majority of the mixtures, especially at low-effect levels, might have implications in the real terrestrial environment.

  17. Inhibition of Voltage-Gated Calcium Channels After Subchronic and Repeated Exposure of PC12 Cells to Different Classes of Insecticides.

    Science.gov (United States)

    Meijer, Marieke; Brandsema, Joske A R; Nieuwenhuis, Desirée; Wijnolts, Fiona M J; Dingemans, Milou M L; Westerink, Remco H S

    2015-10-01

    We previously demonstrated that acute inhibition of voltage-gated calcium channels (VGCCs) is a common mode of action for (sub)micromolar concentrations of chemicals, including insecticides. However, because human exposure to chemicals is usually chronic and repeated, we investigated if selected insecticides from different chemical classes (organochlorines, organophosphates, pyrethroids, carbamates, and neonicotinoids) also disturb calcium homeostasis after subchronic (24 h) exposure and after a subsequent (repeated) acute exposure. Effects on calcium homeostasis were investigated with single-cell fluorescence (Fura-2) imaging of PC12 cells. Cells were depolarized with high-K(+) saline to study effects of subchronic or repeated exposure on VGCC-mediated Ca(2+) influx. The results demonstrate that except for carbaryl and imidacloprid, all selected insecticides inhibited depolarization (K(+))-evoked Ca(2+) influx after subchronic exposure (IC50's: approximately 1-10 µM) in PC12 cells. These inhibitory effects were not or only slowly reversible. Moreover, repeated exposure augmented the inhibition of the K(+)-evoked increase in intracellular calcium concentration induced by subchronic exposure to cypermethrin, chlorpyrifos, chlorpyrifos-oxon, and endosulfan (IC50's: approximately 0.1-4 µM). In rat primary cortical cultures, acute and repeated chlorpyrifos exposure also augmented inhibition of VGCCs compared with subchronic exposure. In conclusion, compared with subchronic exposure, repeated exposure increases the potency of insecticides to inhibit VGCCs. However, the potency of insecticides to inhibit VGCCs upon repeated exposure was comparable with the inhibition previously observed following acute exposure, with the exception of chlorpyrifos. The data suggest that an acute exposure paradigm is sufficient for screening chemicals for effects on VGCCs and that PC12 cells are a sensitive model for detection of effects on VGCCs.

  18. Assessment of potential sublethal effects of various insecticides on key biological traits of the tobacco whitefly, Bemisia tabaci.

    Science.gov (United States)

    He, Yuxian; Zhao, Jianwei; Zheng, Yu; Weng, Qiyong; Biondi, Antonio; Desneux, Nicolas; Wu, Kongming

    2013-01-01

    The tobacco whitefly Bemisia tabaci is one of the most devastating pests worldwide. Current management of B. tabaci relies upon the frequent applications of insecticides. In addition to direct mortality by typical acute toxicity (lethal effect), insecticides may also impair various key biological traits of the exposed insects through physiological and behavioral sublethal effects. Identifying and characterizing such effects could be crucial for understanding the global effects of insecticides on the pest and therefore for optimizing its management in the crops. We assessed the effects of sublethal and low-lethal concentrations of four widely used insecticides on the fecundity, honeydew excretion and feeding behavior of B. tabaci adults. The probing activity of the whiteflies feeding on treated cotton seedlings was recorded by an Electrical Penetration Graph (EPG). The results showed that imidacloprid and bifenthrin caused a reduction in phloem feeding even at sublethal concentrations. In addition, the honeydew excretions and fecundity levels of adults feeding on leaf discs treated with these concentrations were significantly lower than the untreated ones. While, sublethal concentrations of chlorpyrifos and carbosulfan did not affect feeding behavior, honeydew excretion and fecundity of the whitefly. We demonstrated an antifeedant effect of the imidacloprid and bifenthrin on B. tabaci, whereas behavioral changes in adults feeding on leaves treated with chlorpyrifos and carbosulfan were more likely caused by the direct effects of the insecticides on the insects' nervous system itself. Our results show that aside from the lethal effect, the sublethal concentration of imidacloprid and bifenthrin impairs the phloem feeding, i.e. the most important feeding trait in a plant protection perspective. Indeed, this antifeedant property would give these insecticides potential to control insect pests indirectly. Therefore, the behavioral effects of sublethal concentrations of

  19. Exploration of Novel Botanical Insecticide Leads: Synthesis and Insecticidal Activity of β-Dihydroagarofuran Derivatives.

    Science.gov (United States)

    Zhao, Ximei; Xi, Xin; Hu, Zhan; Wu, Wenjun; Zhang, Jiwen

    2016-02-24

    The discovery of novel leads and new mechanisms of action is of vital significance to the development of pesticides. To explore lead compounds for botanical insecticides, 77 β-dihydroagarofuran derivatives were designed and synthesized. Their structures were mainly confirmed by (1)H NMR, (13)C NMR, DEPT-135°, IR, MS, and HRMS. Their insecticidal activity was evaluated against the third-instar larvae of Mythimna separata Walker, and the results indicated that, of these derivatives, eight exhibited more promising insecticidal activity than the positive control, celangulin-V. Particularly, compounds 5.7, 6.6, and 6.7 showed LD50 values of 37.9, 85.1, and 21.1 μg/g, respectively, which were much lower than that of celangulin-V (327.6 μg/g). These results illustrated that β-dihydroagarofuran ketal derivatives can be promising lead compounds for developing novel mechanism-based and highly effective botanical insecticides. Moreover, some newly discovered structure-activity relationships are discussed, which may provide some important guidance for insecticide development.

  20. Resmethrin, the first modern pyrethroid insecticide.

    Science.gov (United States)

    Soderlund, David M

    2015-06-01

    The discovery of resmethrin almost five decades ago was the seminal event in the development of pyrethroid insecticides as important pest management tools, the value of which endures to this day. This brief review considers the development of pyrethroids from the perspective of the discovery of resmethrin. I describe the pathway to the discovery of resmethrin and the unique properties that differentiated it from the pyrethrins and earlier synthetic pyrethroids is described. I also summarize information on metabolic fate and mechanisms of selective toxicity, first elucidated with resmethrin, that have shaped our understanding of pyrethroid toxicology since that time. Finally, I review the discovery pathway that led from resmethrin to the development of the first photostable, agriculturally useful pyrethroids that established the importance of this insecticide class.

  1. Ion channels: molecular targets of neuroactive insecticides.

    Science.gov (United States)

    Raymond-Delpech, Valérie; Matsuda, Kazuhiko; Sattelle, Benedict M; Rauh, James J; Sattelle, David B

    2005-11-01

    Many of the insecticides in current use act on molecular targets in the insect nervous system. Recently, our understanding of these targets has improved as a result of the complete sequencing of an insect genome, i.e., Drosophila melanogaster. Here we examine the recent work, drawing on genetics, genomics and physiology, which has provided evidence that specific receptors and ion channels are targeted by distinct chemical classes of insect control agents. The examples discussed include, sodium channels (pyrethroids, p,p'-dichlorodiphenyl-trichloroethane (DDT), dihydropyrazoles and oxadiazines); nicotinic acetylcholine receptors (cartap, spinosad, imidacloprid and related nitromethylenes/nitroguanidines); gamma-aminobutyric acid (GABA) receptors (cyclodienes, gamma-BHC and fipronil) and L-glutamate receptors (avermectins). Finally, we have examined the molecular basis of resistance to these molecules, which in some cases involves mutations in the molecular target, and we also consider the future impact of molecular genetic technologies in our understanding of the actions of neuroactive insecticides.

  2. Inhibition of voltage-gated calcium channels as common mode of action for (mixtures of) distinct classes of insecticides.

    Science.gov (United States)

    Meijer, Marieke; Dingemans, Milou M L; van den Berg, Martin; Westerink, Remco H S

    2014-09-01

    Humans are exposed to distinct structural classes of insecticides with different neurotoxic modes of action. Because calcium homeostasis is essential for proper neuronal function and development, we investigated the effects of insecticides from different classes (pyrethroid: (α-)cypermethrin; organophosphate: chlorpyrifos; organochlorine: endosulfan; neonicotinoid: imidacloprid) and mixtures thereof on the intracellular calcium concentration ([Ca(2+)]i). Effects of acute (20 min) exposure to (mixtures of) insecticides on basal and depolarization-evoked [Ca(2+)]i were studied in vitro with Fura-2-loaded PC12 cells and high resolution single-cell fluorescence microscopy. The data demonstrate that cypermethrin, α-cypermethrin, endosulfan, and chlorpyrifos concentration-dependently decreased depolarization-evoked [Ca(2+)]i, with 50% (IC50) at 78nM, 239nM, 250nM, and 899nM, respectively. Additionally, acute exposure to chlorpyrifos or endosulfan (10μM) induced a modest increase in basal [Ca(2+)]i, amounting to 68 ± 8nM and 53 ± 8nM, respectively. Imidacloprid did not disturb basal or depolarization-evoked [Ca(2+)]i at 10μM. Following exposure to binary mixtures, effects on depolarization-evoked [Ca(2+)]i were within the expected effect additivity range, whereas the effect of the tertiary mixture was less than this expected additivity effect range. These results demonstrate that different types of insecticides inhibit depolarization-evoked [Ca(2+)]i in PC12 cells by inhibiting voltage-gated calcium channels (VGCCs) in vitro at concentrations comparable with human occupational exposure levels. Moreover, the effective concentrations in this study are below those for earlier described modes of action. Because inhibition of VGCCs appears to be a common and potentially additive mode of action of several classes of insecticides, this target should be considered in neurotoxicity risk assessment studies.

  3. Identification of Insecticidal Constituents from the Essential Oil of Valeriana jatamansi Jones against Liposcelis bostrychophila Badonnel

    Directory of Open Access Journals (Sweden)

    Xin Chao Liu

    2013-01-01

    Full Text Available The aim of this research was to determine chemical composition and insecticidal activities of the essential oil of Valeriana jatamansi Jones roots against booklice, Liposcelis bostrychophila Badonnel, and to isolate insecticidal constituents from the oil. Essential oil of V. jatamansi was obtained by hydrodistillation and analyzed by GC-MS. A total of 27 components in the essential oil were identified. The major compounds were patchoulol (24.3%, α-bulnesene (13.8%, isovaleric acid (12.9%, α-guaiene (8.7%, and 3-methylvaleric acid (8.4%. Based on bioactivity-guided fractionation, isovaleric acid, 3-methylvaleric acid, and patchoulol were isolated and identified as the active constituents. The essential oil exhibited contact toxicity against L. bostrychophila with an LC50 value of 236.4 μg/cm2. Patchoulol (LC50 = 61.35 μg/cm2 exhibited stronger acute toxicity than 3-methylvaleric acid (LC50 = 210.69 μg/cm2 against the booklice. The essential oil also possessed fumigant toxicity against L. bostrychophila with an LC50 value of 6.0 mg/L, while 3-methylvaleric acid and isovaleric acid had LC50 values of 5.53 mg/L and 5.67 mg/L against the booklice, respectively. The results indicated that the essential oil and its constituent compounds have potential to develop into natural insecticides or fumigants for control of insects in stored grains.

  4. BACILLUS THURINGIENSIS ELASTASES WITH INSECTICIDE ACTIVITY

    OpenAIRE

    E. V. Matseliukh; N. A. Nidialkova; V. V. Krout'; L. D. Varbanets; A. V. Kalinichenko; V. F. Patyka

    2015-01-01

    The purpose of the research was a screening of proteases with elastase activity among Bacillus thuringiensis strains, their isolation, partially purification, study of physicochemical properties and insecticide activity in relation to the larvae of the Colorado beetle. The objects of the investigation were 18 strains of B. thuringiensis, isolated from different sources: sea water, dry biological product "Bitoksibatsillin" and also from natural populations of Colorado beetles of the Crimea, Kh...

  5. Insecticide control in a Dengue epidemics model

    CERN Document Server

    Rodrigues, Helena Sofia; Torres, Delfim F M

    2010-01-01

    A model for the transmission of dengue disease is presented. It consists of eight mutually-exclusive compartments representing the human and vector dynamics. It also includes a control parameter (insecticide) in order to fight the mosquitoes. The main goal of this work is to investigate the best way to apply the control in order to effectively reduce the number of infected humans and mosquitoes. A case study, using data of the outbreak that occurred in 2009 in Cape Verde, is presented.

  6. Insecticide resistance in Bemisia tabaci from Cyprus

    Institute of Scientific and Technical Information of China (English)

    Vassilis Vassiliou; Maria Emmanouilidou; Andreas Perrakis; Evangelia Morou; John Vontas; Anastasia Tsagkarakou; Emmanouil Roditakis

    2011-01-01

    A comprehensive study on the Bemisia tabaci(biotype B)resistance to neonicotinoid insecticides imidacloprid,acetamiprid and thiamethoxam,and pyrethroid bifenthrin was conducted in Cyprus.The resistance level to eight field-collected B.tabaci populations was investigated.The activities of enzymes involved in metabolic detoxification and the frequencies of pyrethroid and organophosphates target site resistance mutations were determined.Moderate to high levels of resistance were detected for imidacloprid(resistance factor[RF]77-392)and thiamethoxam(RF 50-164)while low resistance levels were observed for acetamiprid(RF 7-12).Uniform responses by the Cypriot whiteflies could be observed against all neonicotinoid insecticides.No cross-resistance between the neonicotinoids was detected as well as no association with the activity of the P450 microsomal oxidases.Only imidacloprid resistance correlated with carboxylesterase activity.Low to extremely high resistance was observed for insecticide bifenthrin(RF 49-1 243)which was associated with the frequency of the resistant allele in the sodium channel gene but not with the activity of the detoxification enzymes.Finally,the F331W mutation in the acetylcholinesterase enzyme ace1 gene was fixed in all B.tabaci populations from Cyprus.

  7. Insecticide Resistance and Management Strategies in Urban Ecosystems

    Directory of Open Access Journals (Sweden)

    Fang Zhu

    2016-01-01

    Full Text Available The increased urbanization of a growing global population makes imperative the development of sustainable integrated pest management (IPM strategies for urban pest control. This emphasizes pests that are closely associated with the health and wellbeing of humans and domesticated animals. Concurrently there are regulatory requirements enforced to minimize inadvertent exposures to insecticides in the urban environment. Development of insecticide resistance management (IRM strategies in urban ecosystems involves understanding the status and mechanisms of insecticide resistance and reducing insecticide selection pressure by combining multiple chemical and non-chemical approaches. In this review, we will focus on the commonly used insecticides and molecular and physiological mechanisms underlying insecticide resistance in six major urban insect pests: house fly, German cockroach, mosquitoes, red flour beetle, bed bugs and head louse. We will also discuss several strategies that may prove promising for future urban IPM programs.

  8. Multiple insecticide resistance: an impediment to insecticide-based malaria vector control program.

    Directory of Open Access Journals (Sweden)

    Delenasaw Yewhalaw

    Full Text Available BACKGROUND: Indoor Residual Spraying (IRS, insecticide-treated nets (ITNs and long-lasting insecticidal nets (LLINs are key components in malaria prevention and control strategy. However, the development of resistance by mosquitoes to insecticides recommended for IRS and/or ITNs/LLINs would affect insecticide-based malaria vector control. We assessed the susceptibility levels of Anopheles arabiensis to insecticides used in malaria control, characterized basic mechanisms underlying resistance, and evaluated the role of public health use of insecticides in resistance selection. METHODOLOGY/PRINCIPAL FINDINGS: Susceptibility status of An. arabiensis was assessed using WHO bioassay tests to DDT, permethrin, deltamethrin, malathion and propoxur in Ethiopia from August to September 2009. Mosquito specimens were screened for knockdown resistance (kdr and insensitive acetylcholinesterase (ace-1(R mutations using AS-PCR and PCR-RFLP, respectively. DDT residues level in soil from human dwellings and the surrounding environment were determined by Gas Chromatography with Electron Capture Detector. An. arabiensis was resistant to DDT, permethrin, deltamethrin and malathion, but susceptible to propoxur. The West African kdr allele was found in 280 specimens out of 284 with a frequency ranged from 95% to 100%. Ace-1(R mutation was not detected in all specimens scored for the allele. Moreover, DDT residues were found in soil samples from human dwellings but not in the surrounding environment. CONCLUSION: The observed multiple-resistance coupled with the occurrence of high kdr frequency in populations of An. arabiensis could profoundly affect the malaria vector control programme in Ethiopia. This needs an urgent call for implementing rational resistance management strategies and integrated vector control intervention.

  9. The use of insecticides to control insect pests

    Directory of Open Access Journals (Sweden)

    M Wojciechowska

    2016-07-01

    Full Text Available Pesticides are used as plants protection products. Among those, insecticides serve as agents to control insects. When incorrectly applied, however these substances may negatively affect people's health and natural environment. Administration routes of insecticides depend on many factors and vary from spraying to fertilizers. These different methods influence how insects prey and how pests develop. Additionally, too frequent use of the same chemicals can lead to development of resistance of insects to these insecticides. In order to prevent occurrence of negative effects of insecticides on surroundings, the effects of these compounds should be studied

  10. Podophyllotoxin-derived insecticidal agents: part XIII--evaluation of insecticidal activity of podophyllotoxin derivatives against Brontispa longissima.

    Science.gov (United States)

    Liu, Ying-Qian; Feng, Gang; Yang, Liu; Jing-Zhang; Li, Hong-Yu

    2011-09-01

    In an attempt to find the biorational insecticides for Brontispa longissima control, 12 podophyllotoxin (PPT) analogues were tested for their insecticidal activity against the fifth-instar larvae of B. longissima in vivo for the first time. Among all the tested compounds, especially compounds 6 and 8 showed more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. The different insecticidal activity range of compounds 1-12 indicated that the variation of chemical structures in the PPT skeleton markedly affected the activity profiles of this compound class, and some important structure-activity relationship information has been revealed. Together, these preliminary results may be useful in guiding further modification of PPTs in the development of potential new insecticides.

  11. Insecticidal Constituents and Activity of Alkaloids from Cynanchum mongolicum.

    Science.gov (United States)

    Ge, Yang; Liu, Pingping; Yang, Rui; Zhang, Liu; Chen, Hongxing; Camara, Ibrahima; Liu, Yiqing; Shi, Wangpeng

    2015-09-21

    Based on MS and NMR data and bioassay-guided tracing, three insecticidal alkaloids I, II and III from Cynanchum mongolicum were identified to be antofine N-oxide, antofine and tylophorine. Alkaloid I was more toxic than alkaloids II and III, but they were less active against Spodoptera litura than total alkaloids. The contact toxicity from these alkaloids against the aphid Lipaphis erysimi was significant, as the 24 h-LC50 values of alkaloids I, II, III and total alkaloids were 292.48, 367.21, 487.791 and 163.52 mg/L, respectively. The development disruption of S. litura larvae was tested, the pupation and emergence rates of S. litura decreased and the acute mortality of S. litura increased significantly by day 3 after being injected in their body cavity with 10-40 mg/L of total alkaloid. The ecdysone titer of treated S. litura larvae and prepupae declined with increasing alkaloid concentration. The alkaloids of Cynanchum mongolicum are potential insect growth inhibitors.

  12. Improvement in organophosphorus hydrolase activity of cell surface-engineered yeast strain using Flo1p anchor system

    OpenAIRE

    Fukuda, Takeshi; Tsuchiyama, Kouta; Makishima, Hirokazu; Takayama, Katsumi; Mulchandani, Ashok; Kuroda, Kouichi; Ueda, Mitsuyoshi; Suye, Shin-ichiro

    2010-01-01

    Organophosphorus hydrolase (OPH) hydrolyzes organophosphorus esters. We constructed the yeast-displayed OPH using Flo1p anchor system. In this system, the N-terminal region of the protein was fused to Flo1p and the fusion protein was displayed on the cell surface. Hydrolytic reactions with paraoxon were carried out during 24 h of incubation of OPH-displaying cells at 30°C. p-Nitrophenol produced in the reaction mixture was detected by HPLC. The strain with highest activity showed 8-fold great...

  13. Levels and distribution of organophosphorus flame retardants and plasticizers in fishes from Manila Bay, the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joon-Woo [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Senior Research Fellow Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Isobe, Tomohiko, E-mail: t.isobe@agr.ehime-u.ac.jp [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Senior Research Fellow Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Chang, Kwang-Hyeon [Department of Environmental Science and Engineering, Kyung Hee University, Seochen-dong 1, Giheung-gu, Yongin-Si, Gyeonggi-Do 446-701 (Korea, Republic of); Amano, Atsuko [National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8567 (Japan); Maneja, Rommel H.; Zamora, Peter B.; Siringan, Fernando P. [Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101 (Philippines); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

    2011-12-15

    Organophosphorus compounds (OPCs) and stable isotope ratios ({delta}{sup 13}C and {delta}{sup 15}N) were determined in 58 fishes belonging to 20 species collected from Manila Bay, the Philippines. OPCs were detected in most of the samples and found up to {mu}g/g lw (lipid weight) level, suggesting their ubiquitous presence in the coastal marine environment of the Philippines. Higher levels (>1000 ng/g lw) of total OPCs were determined in yellowstriped goatfish, silver sillago, tripletail wrasse and bumpnose trevally indicates either their active uptake from ambient water or lower metabolic capacity of these species. Levels of triphenyl phosphate (TPhP) in demersal species showed a positive correlation with {delta}{sup 15}N, indicating that TPhP was adsorbed onto the particle, settled down to the bottom sediment and accumulated through the benthic food web rather than the pelagic. Estimated dietary intake of OPCs in Manila Bay fishes were four to five orders of magnitude lower than the proposed reference dose (RfD). - Highlights: > Organophosphorus compounds (OPCs) were determined in fish from Manila Bay. > OPCs were detected up to {mu}g/g lw, suggesting ubiquitous environmental contamination. > Among the 9 targeted OPCs, TEHP and TEP were found as the predominant compounds. > Estimated dietary intake through fish consumption was 4-5 orders of magnitude lower than RfD. > This is the first report on OPCs pollution in marine environment of Southeast Asia. - Occurrence and bioaccumulation of organophosphorus compounds (OPCs) were determined in fishes from Manila Bay.

  14. The insecticide resistance in two planthoppers from three areas to three insecticides

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ Migrating insects brown planthopper (BPH), Nilaparata lugens Stal and white-backed planthopper (WBPH), Sogatellafurcifera Horvath are both most harmful insects on rice in China. Chemical control is thought to be the best way to manage them, but it may cause insecticide resistance.

  15. Reversed micellization in metal-organophosphorus extractant systems of commercial importance

    Energy Technology Data Exchange (ETDEWEB)

    Gaonkar, A.G.; Neuman, R.D.

    1986-01-01

    The interfacial tension behavior in liquid/liquid organophosphorus extractant systems containing di(2-ethylhexyl)phosphoric acid (HDEHP) and metal ions such as Ca/sup 2 +/, Cu/sup 2 +/, Co/sup 2 +/, Ni/sup 2 +/, or Zn/sup 2 +/ was investigated. Data of vapor pressure osmometry and Karl Fischer titrimetry, in addition to those of interfacial tension, distribution equilibria and extraction kinetics, support the view that reversed micelles can form in extraction systems which employ HDEHP. 24 refs., 7 figs.

  16. Simple, specific analysis of organophosphorus and carbamate pesticides in sediments using column extraction and gas chromatography

    Science.gov (United States)

    Belisle, A.A.; Swineford, D.M.

    1988-01-01

    A simple, specific procedure was developed for the analysis of organophosphorus and carbamate pesticides in sediment. The wet soil was mixed with anhydrous sodium sulfate to bind water and the residues were column extracted in acetone:methylene chloride (1:l,v/v). Coextracted water was removed by additional sodium sulfate packed below the sample mixture. The eluate was concentrated and analyzed directly by capillary gas chromatography using phosphorus and nitrogen specific detectors. Recoveries averaged 93 % for sediments extracted shortly after spiking, but decreased significantly as the samples aged.

  17. Monitoring of organophosphorus pesticide residues in vegetables of agricultural area in Venezuela.

    Science.gov (United States)

    Quintero, América; Caselles, María J; Ettiene, Gretty; de Colmenares, Nélida G; Ramírez, Tibisay; Medina, Deisy

    2008-10-01

    The purpose of this study was to determine the residues of seven pesticides organophosphorus (methamidophos, diazinon, chlorpyriphos, parathion-methyl, dimethoate, malathion and tetrachlorvinphos), in some vegetables like: potato, lettuce, tomato, onion, red pepper and green onion cultivated in José María Vargas County in Táchira State, Venezuela. The research permitted to detect that 48.0% of the samples were contaminated with some of the pesticides studied. Methamidophos was founded in the vegetables in the rank of 6.3%-65.5%. The results show that 16.7% of the samples tested have residues higher than the maximum limits permitted.

  18. Unidirectional cross-tolerance between the carbamate insecticide propoxur and the organophosphate disulfoton in mice.

    Science.gov (United States)

    Costa, L G; Murphy, S D

    1983-01-01

    Previous studies have shown that subchronic treatment of mice with the organophosphate insecticide, disulfoton, or the carbamate insecticide, propoxur, leads to the development of tolerance to their toxicity. Tolerance to disulfoton was due to a decrease in the number of muscarinic cholinergic receptors, while tolerance to propoxur appeared to be due to an induction of hepatic microsomal enzymes. In the present study we investigated if cross-tolerance between disulfoton and propoxur would occur. Cross-tolerance was evaluated by measuring acute toxicities, cholinesterase and carboxylesterase inhibition and hypothermic and antinociceptive effects. Mice tolerant to propoxur were cross-tolerant to the hypothermic and anticholinesterase effects of disulfoton. Similarly, when mice were pretreated with the microsomal enzyme inducer, phenobarbital, the toxicity of disulfoton was decreased. Mice made tolerant to disulfoton were cross-tolerant to the organophosphate chlorpyrifos, but were more sensitive than controls to the toxicity of propoxur. The acute toxicity of the organophosphate malathion was also increased in disulfoton-tolerant mice. Propoxur is metabolized by mixed function oxidases and possibly by a carboxylesterase. While hepatic microsomal enzymes appeared to be unchanged in disulfoton-tolerant mice, brain and liver carboxylesterase activities were significantly inhibited. Pretreatment of mice with the specific carboxylesterase inhibitor triorthotolylphosphate is known to greatly potentiate the toxicity of malathion and also potentiated, to a lesser extent, the toxicity of propoxur.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. 不同类型杀虫剂对北京地区Q型烟粉虱的毒力测定%Toxicities of Different Insecticides to Q-Type Bemisia tabaci in Beijing

    Institute of Scientific and Technical Information of China (English)

    宫亚军; 石宝才; 朱亮; 康总江; 王泽华; 魏书军

    2011-01-01

    [目的]近年来Q型烟粉虱在我国许多地区危害严重,但关于Q型烟粉虱对杀虫剂的抗性研究甚少.采用浸叶生测法分别测定了7种杀虫剂对北京地区Q型烟粉虱成虫的毒力.[结果]结果表明7种药剂对烟粉虱成虫的毒力排序:阿维菌素>甲氨基阿维菌素苯甲酸盐>多杀霉素>啶虫脒>吡虫啉>毒死蜱>敌敌畏.[结论]在北京地区防治烟粉虱时应选用敏感性高的抗生素类杀虫剂,交替使用新烟碱类农药,限制使用有机磷类农药.%[Aims] Q-type whitefly Bemisia tabaci caused serious damages in many areas in China in recent years.However, there are few studies on resistance of this pest to insecticides. Here, we tested the toxicities of seven insecticides to adults of Q-type B. tabaci by leaf-dipping method in Beijing. [Results] The results showed that the descending order of toxicity of these seven insecticides to B. tabaci adults is abamectin, emamectin benzoate, spinosad, acetamiprid,imidacloprid, chlorpyrifos, dichlorvos. [Conclusions] Thus, antibiotic insecticides with high sensitivity and alternate use of neonicotinoid pesticides are recommended in controlling whitefly Bemisia tabaci in Beijing areas. However, usage of organophosphorus pesticides should be restricted.

  20. BACILLUS THURINGIENSIS ELASTASES WITH INSECTICIDE ACTIVITY

    Directory of Open Access Journals (Sweden)

    E. V. Matseliukh

    2015-10-01

    Full Text Available The purpose of the research was a screening of proteases with elastase activity among Bacillus thuringiensis strains, their isolation, partially purification, study of physicochemical properties and insecticide activity in relation to the larvae of the Colorado beetle. The objects of the investigation were 18 strains of B. thuringiensis, isolated from different sources: sea water, dry biological product "Bitoksibatsillin" and also from natural populations of Colorado beetles of the Crimea, Kherson, Odesa, Mykolaiv and Zaporizhiia regions of Ukraine. Purification of enzymes with elastase activity isolated from above mentioned strains was performed by gel-chromatography and insecticide activity was studied on the 3–4 larvae instar of Colorado beetle. The ability of a number of B. thuringiensis strains to synthesize the proteases with elastase activity has been established. The most active were enzymes obtained from strains IMV B-7465, IMV B-7324 isolated from sea water, and strains 9, 902, Bt-H and 0-239 isolated from Colorado beetles. The study of the physicochemical properties of the partially purified proteases of these strains showed that they belonged to enzymes of the serine type. Peptidases of a number of B. thuringiensis strains (IMV B-7324, IMV B-7465, 902, 0-239, 9 are metal-dependent enzymes. Optimal conditions of action of all tested enzymes are the neutral and alkaline рН values and the temperatures of 30–40 °С. The studies of influence of the complex enzyme preparations and partially purified ones of B. thuringiensis strains on the larvae instar of Colorado beetles indicated that enzymes with elastase activity could be responsible for insecticide action of the tested strains.

  1. Cytotoxic and Insecticidal Activities of Derivatives of Harmine, a Natural Insecticidal Component Isolated from Peganum harmala

    Directory of Open Access Journals (Sweden)

    Guohua Zhong

    2010-11-01

    Full Text Available In a continuing effort to develop novel β-carbolines endowed with better insecticidal activity, a simple high-yielding method for the synthesis of harmine compounds starting from L-tryptophan has been developed and a series of 1,3-substituted β-carboline derivatives have been synthesized and evaluated for their cytotoxicity against insect cultured Sf9 cell line in vitro and insecticidal activities against 4th instar larvae of mosquitos, Culex pipiens quinquefasciatus and mustard aphid, Lipaphis erysimi. The results demonstrated that 1-phenyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (compound 2 and methyl 1-phenyl-β-carboline-3-carboxylate (compound 13 represented the best potential compounds, with Sf9 cells inhibition rates of 71.55% and 60.21% after 24 h treatment at concentrations of 50–200 mg/L, respectively. Both compounds 2 and 13 also showed strong insecticidal activity towards 4th instar larvae of mosquitos with LC50 values of 20.82 mg/L and 23.98 mg/L, and their LC90 values were 88.29 mg/L and 295.13 mg/L, respectively. Furthermore, the LC50 values of compounds 2 and 13 against mustard aphids were 53.16 mg/L and 68.05 mg/L, and their LC90 values were 240.10 mg/L and 418.63 mg/L after 48 h treatment. The in vitro cytotoxicity of these compounds was consistent with the insecticidal activity in vivo. The results indicated that the 1- and 3-positions of the β-carboline ring deserve further investigation to develop biorational insecticides based on the natural compound harmine as a lead compound.

  2. Methomyl-Induced Severe Acute Pancreatitis: Possible Etiological Association

    OpenAIRE

    Ioannides M; Christodoulides P; Symeonides M; Vounou E; Tsikkos S; Achillews G; Koukouvas M; Makrides C

    2005-01-01

    CONTEXT: N-methyl carbamate insecticides are widely used in homes, gardens and agriculture. They share the capacity to inhibit cholinesterase enzymes with organophosphates and therefore share similar symptomatology during acute and chronic exposures. One of the serious effects of organophosphate and carbamate intoxication is the development of acute pancreatitis and subsequent intrapancreatic fluid formation. CASE REPORT: An 18-year old Caucasian man was admitted to our Intensive Care Unit wi...

  3. Experience of Diagnosis and Treatment of Patients with Organophosphorus Pesticide Poisoning%有机磷中毒的诊治心得体会

    Institute of Scientific and Technical Information of China (English)

    王文德

    2015-01-01

    目的对有机磷中毒的诊断和治疗进行讨论。方法将1例急性有机磷中毒临床资料进行回顾并将治疗结果进行分析。结果患者康复出院。结论对有机磷中毒患者进行准确快速的诊断后及时给与复能剂与解毒剂,防止阿托品中毒,在改善患者的治愈率及身心健康方面所起的作用是明显的。%Objective To discuss the diagnosis and treatment of organophosphate poisoning. Methods Review the case of acute organophosphate poisoning clinical information and treatment results were analyzed. Results Patients rehabilitation hospital discharge.Conclusion Accurate rapid diagnosis to patients with organophosphorus poisoning after timely give reply to agent and antidote, prevent atropine poisoning, in improving the patient's cure rate and the role of the physical and mental health is obvious.

  4. In vivo microdialysis and electroencephalographic activity in freely moving guinea pigs exposed to organophosphorus nerve agents sarin and VX: analysis of acetylcholine and glutamate.

    Science.gov (United States)

    O'Donnell, John C; McDonough, John H; Shih, Tsung-Ming

    2011-12-01

    Organophosphorus nerve agents such as sarin (GB) and VX irreversibly inhibit acetylcholinesterase, causing a buildup of acetylcholine (ACh) in synapses and neuromuscular junctions, which leads to excess bronchial secretions, convulsions, seizures, coma, and death. Understanding the unique toxic characteristics of different nerve agents is vital in the effort to develop broad spectrum medical countermeasures. To this end, we employed a repeated measure multivariate design with striatal microdialysis collection and high-performance liquid chromatography analysis to measure changes in concentrations of several neurotransmitters (ACh, glutamate, aspartate, GABA) in the same samples during acute exposure to GB or VX in freely moving guinea pigs. Concurrent with microdialysis collection, we used cortical electrodes to monitor brain seizure activity. This robust double multivariate design provides greater fidelity when comparing data while also reducing the required number of subjects. No correlation between nerve agents' propensity for causing seizure and seizure-related lethality was observed. The GB seizure group experienced more rapid and severe cholinergic toxicity and lethality than that of the VX seizure group. Seizures generated from GB and VX exposure resulted in further elevation of ACh level and then a gradual return to baseline. Glutamate levels increased in the GB, but not in the VX, seizure group. There were no consistent changes in either aspartate or GABA as a result of either nerve agent. These observations reinforce findings with other nerve agents that seizure activity per se contributes to the elevated levels of brain ACh observed after nerve agent exposure.

  5. Design, Synthesis and Insecticidal Activities of Novel Phenyl Substituted Isoxazolecarboxamides

    Institute of Scientific and Technical Information of China (English)

    LIU Peng-fei; ZHANG Ji-feng; YAN Tao; XIONG Li-xia; LI Zheng-ming

    2012-01-01

    Thirteen novel phenyl substituted isoxazolecarboxamides were synthesized,and their structures were characterized by 1H NMR,elementary analysis and high-resolution mass spectrometry(HRMS) techniques.Their evaluated insecticidal activities against oriental armyworm(Mythimna separata) indicate that the phcnyl substituted isoxazolecarboxamides exhibited moderate insecticidal activities,among which compounds 9c and 9k showed comparatively higher activities.

  6. Botanical insecticides inspired by plant-herbivore chemical interactions.

    Science.gov (United States)

    Miresmailli, Saber; Isman, Murray B

    2014-01-01

    Plants have evolved a plethora of secondary chemicals to protect themselves against herbivores and pathogens, some of which have been used historically for pest management. The extraction methods used by industry render many phytochemicals ineffective as insecticides despite their bioactivity in the natural context. In this review, we examine how plants use their secondary chemicals in nature and compare this with how they are used as insecticides to understand why the efficacy of botanical insecticides can be so variable. If the commercial production of botanical insecticides is to become a viable pest management option, factors such as production cost, resource availability, and extraction and formulation techniques need be considered alongside innovative application technologies to ensure consistent efficacy of botanical insecticides.

  7. An Operational Framework for Insecticide Resistance Management Planning.

    Science.gov (United States)

    Chanda, Emmanuel; Thomsen, Edward K; Musapa, Mulenga; Kamuliwo, Mulakwa; Brogdon, William G; Norris, Douglas E; Masaninga, Freddie; Wirtz, Robert; Sikaala, Chadwick H; Muleba, Mbanga; Craig, Allen; Govere, John M; Ranson, Hilary; Hemingway, Janet; Seyoum, Aklilu; Macdonald, Michael B; Coleman, Michael

    2016-05-01

    Arthropod vectors transmit organisms that cause many emerging and reemerging diseases, and their control is reliant mainly on the use of chemical insecticides. Only a few classes of insecticides are available for public health use, and the increased spread of insecticide resistance is a major threat to sustainable disease control. The primary strategy for mitigating the detrimental effects of insecticide resistance is the development of an insecticide resistance management plan. However, few examples exist to show how to implement such plans programmatically. We describe the formulation and implementation of a resistance management plan for mosquito vectors of human disease in Zambia. We also discuss challenges, steps taken to address the challenges, and directions for the future.

  8. Averting a malaria disaster: will insecticide resistance derail malaria control?

    Science.gov (United States)

    Hemingway, Janet; Ranson, Hilary; Magill, Alan; Kolaczinski, Jan; Fornadel, Christen; Gimnig, John; Coetzee, Maureen; Simard, Frederic; Roch, Dabiré K; Hinzoumbe, Clément Kerah; Pickett, John; Schellenberg, David; Gething, Peter; Hoppé, Mark; Hamon, Nicholas

    2016-04-23

    World Malaria Day 2015 highlighted the progress made in the development of new methods of prevention (vaccines and insecticides) and treatment (single dose drugs) of the disease. However, increasing drug and insecticide resistance threatens the successes made with existing methods. Insecticide resistance has decreased the efficacy of the most commonly used insecticide class of pyrethroids. This decreased efficacy has increased mosquito survival, which is a prelude to rising incidence of malaria and fatalities. Despite intensive research efforts, new insecticides will not reach the market for at least 5 years. Elimination of malaria is not possible without effective mosquito control. Therefore, to combat the threat of resistance, key stakeholders need to rapidly embrace a multifaceted approach including a reduction in the cost of bringing new resistance management methods to market and the streamlining of associated development, policy, and implementation pathways to counter this looming public health catastrophe.

  9. Fipronil insecticide toxicology: oxidative stress and metabolism.

    Science.gov (United States)

    Wang, Xu; Martínez, María Aránzazu; Wu, Qinghua; Ares, Irma; Martínez-Larrañaga, María Rosa; Anadón, Arturo; Yuan, Zonghui

    2016-11-01

    Fipronil (FIP) is widely used across the world as a broad-spectrum phenylpyrazole insecticide and veterinary drug. FIP was the insecticide to act by targeting the γ-aminobutyric acid (GABA) receptor and has favorable selective toxicity towards insects rather than mammals. However, because of accidental exposure, incorrect use of FIP or widespread FIP use leading to the contamination of water and soil, there is increasing evidence that FIP could cause a variety of toxic effects on animals and humans, such as neurotoxic, hepatotoxic, nephrotoxic, reproductive, and cytotoxic effects on vertebrate and invertebrates. In the last decade, oxidative stress has been suggested to be involved in the various toxicities induced by FIP. To date, few reviews have addressed the toxicity of FIP in relation to oxidative stress. The focus of this article is primarily intended to summarize the progress in research associated with oxidative stress as a possible mechanism for FIP-induced toxicity as well as metabolism. The present review reports that studies have been conducted to reveal the generation of reactive oxygen species (ROS) and oxidative stress as a result of FIP treatment and have correlated them with various types of toxicity. Furthermore, the metabolism of FIP was also reviewed, and during this process, various CYP450 enzymes were involved and oxidative stress might occur. The roles of various compounds in protecting against FIP-induced toxicity based on their anti-oxidative effects were also summarized to further understand the role of oxidative stress in FIP-induced toxicity.

  10. Risks of neonicotinoid insecticides to honeybees.

    Science.gov (United States)

    Fairbrother, Anne; Purdy, John; Anderson, Troy; Fell, Richard

    2014-04-01

    The European honeybee, Apis mellifera, is an important pollinator of agricultural crops. Since 2006, when unexpectedly high colony losses were first reported, articles have proliferated in the popular press suggesting a range of possible causes and raising alarm over the general decline of bees. Suggested causes include pesticides, genetically modified crops, habitat fragmentation, and introduced diseases and parasites. Scientists have concluded that multiple factors in various combinations-including mites, fungi, viruses, and pesticides, as well as other factors such as reduction in forage, poor nutrition, and queen failure-are the most probable cause of elevated colony loss rates. Investigators and regulators continue to focus on the possible role that insecticides, particularly the neonicotinoids, may play in honeybee health. Neonicotinoid insecticides are insect neurotoxicants with desirable features such as broad-spectrum activity, low application rates, low mammalian toxicity, upward systemic movement in plants, and versatile application methods. Their distribution throughout the plant, including pollen, nectar, and guttation fluids, poses particular concern for exposure to pollinators. The authors describe how neonicotinoids interact with the nervous system of honeybees and affect individual honeybees in laboratory situations. Because honeybees are social insects, colony effects in semifield and field studies are discussed. The authors conclude with a review of current and proposed guidance in the United States and Europe for assessing the risks of pesticides to honeybees.

  11. Determination of selected pesticides in water samples adjacent to agricultural fields and removal of organophosphorus insecticide chlorpyrifos using soil bacterial isolates

    Science.gov (United States)

    Hossain, M. S.; Chowdhury, M. Alamgir Zaman; Pramanik, Md. Kamruzzaman; Rahman, M. A.; Fakhruddin, A. N. M.; Alam, M. Khorshed

    2015-06-01

    The use of pesticide for crops leads to serious environmental pollution, therefore, it is essential to monitor and develop approaches to remove pesticide from contaminated environment. In this study, water samples were collected to monitor pesticide residues, and degradation of chlorpyrifos was also performed using soil bacteria. Identification of pesticide residues and determination of their levels were performed by high-performance liquid chromatography with photodiode array detector. Among 12 samples, 10 samples were found contaminated with pesticides. Chlorpyrifos was detected in four tested samples and concentrations ranged from 3.27 to 9.31 μg/l whereas fenitrothion ranging from (Below Detection Limit, pesticide residues in water, to protect the aquatic environment. Chlorpyrifos degrading bacterial isolates can be used to clean up environmental samples contaminated with the organophosphate pesticides.

  12. Determination of eight selected organophosphorus insecticides in postmortem blood samples using solid-phase extraction and gas chromatography/mass spectrometry.

    Science.gov (United States)

    Raposo, R; Barroso, M; Fonseca, S; Costa, S; Queiroz, J A; Gallardo, E; Dias, M

    2010-11-15

    A simple, rapid and sensitive method is described for the determination of omethoate, dimethoate, diazinon, chlorpyrifos, parathion-ethyl, chlorfenvinphos, quinalphos and azinphos-ethyl in postmortem whole blood samples. The analytes and internal standard (ethion) were isolated from the matrix by solid-phase extraction, and were analysed by gas chromatography/mass spectrometry in the selected ion monitoring mode. The method has shown to be selective after analysis of postmortem samples of 40 different origins. Calibration curves were established between 0.05 (0.1 for omethoate) and 25 µg/mL, and the values obtained for intra- and interday precision and accuracy were within the criteria usually accepted for bioanalytical method validation. Lower limits of quantitation were 50 ng/mL for all compounds, except for omethoate (100 ng/mL); the limits of identification of the method were 25 ng/mL for all analytes, except for omethoate, for which 50 ng/mL was obtained. Absolute recovery was determined at three concentration levels, and ranged from 31 to 108%. The proposed method is simple and fast, and can be routinely applied in the determination of these compounds in postmortem whole blood samples within the scope of forensic toxicology. In addition, mass spectrometry has demonstrated to be a powerful and indispensable tool for the unequivocal identification of the analytes, since the acceptance criteria were accomplished even at very low levels, thus allowing obtaining forensically valid and sound results.

  13. Determination of polar organophosphorus pesticides in vegetables and fruits using liquid chromatography with tandem mass spectrometry: Selection of extraction solvent

    NARCIS (Netherlands)

    Mol, H.G.J.; Dam, R.C.J. van; Steijger, O.M.

    2003-01-01

    A method based on liquid chromatography (LC)-mass spectrometry (MS)/MS was developed for sensitive determination of a number of less gas chromatography (GC)-amenable organophosphorus pesticides (OPs; acephate, methamidophos, monocrotophos, omethoate, oxydemeton-methyl and vamidothion) in cabbage and

  14. Determination of polar organophosphorus pesticides in aqueous samples by direct injection using liquid chromatography : tandem mass spectrometry

    NARCIS (Netherlands)

    Ingelse, B.A.; Dam, R.C.J. van; Vreeken, R.J.; Mol, H.G.J.; Steijger, O.M.

    2001-01-01

    It was demonstrated that four out of six of the very polar organophosphorus pesticides (OPs), i.e. acephate, methamidophos, monocrotophos, omethoate, oxydemeton-methyl and vamidothion, could not be extracted from water using commonly available SPE cartridges. In addition, GC analysis on all six comp

  15. a Enzyme-Based Electrochemical Sensor for Sensitive Detection of Organophosphorus Pesticides

    Science.gov (United States)

    Zhou, Nong; Li, Chengyong; Mo, Rijian; Zhang, Peng; He, Lei; Nie, Fanghong; Su, Weiming; Liu, Shucheng; Gao, Jing; Shao, Haiyan; Qian, Zhong-Ji; Ji, Hongwu

    2016-12-01

    A sensitive and fast sensor for quantitative detection of organophosphorus pesticides (OPs) is obtained using acetylcholinesterase (AChE) biosensor based on graphene oxide (GO)-chitosan (CS) composite film. This new biosensor is prepared via depositing GO-CS composite film on glassy carbon electrode (GCE) and then assembling AChE on the composite film. The GO-CS composite film shows an excellent biocompatibility with AChE and enhances immobilization efficiency of AChE. GO homogeneously disperses in the GO-CS composite films and exhibits excellent electrocatalytic activity to thiocholine oxidation, which is from acetylthiocholine catalyzed by AChE. The results show that the inhibition of carbaryl/trichlorfon on AChE activity is proportional to the concentration of carbaryl/trichlorfon. The detection of linear range for carbaryl is from 10nM to 100nM and the correlation coefficients of 0.993. The detection limit for carbaryl is calculated to be about 2.5nM. In addition, the detection of linear range for trichlorfon is from 10nM to 60nM and the correlation coefficients of 0.994. The detection limit for trichlorfon is calculated to be about 1.2nM. This biosensor provides a new promising tool for trace organophosphorus pesticide detection.

  16. Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

    Institute of Scientific and Technical Information of China (English)

    LIU Xian-jin; YAN Chun-rong; LIU Yuan; YU Xiang-yang; ZHANG Cun-zheng

    2008-01-01

    Diethylphosphono acetic acid (DPA) was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method (AEM) or 1-ethyl-3-(3-dimethylaminopropyl)-carbodimide method (EDC). The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay (CI-ELISA). A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL-1 and an I50 value of 0.182 ug mL-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 ug mL-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semi-quantitation determination of the above former five organophosphorus pesticides.

  17. Investigation of the toxicity of some organophosphorus pesticides in a repeated dose study in rats.

    Science.gov (United States)

    Baconi, Daniela Luiza; Bârcă, Maria; Manda, Gina; Ciobanu, Anne Marie; Bălălău, C

    2013-01-01

    The study aimed to the investigation of the toxicity of organophosphorus pesticides malathion (MLT) and diazinon (DZN) in Wistar rats in a repeated dose study for 35 days. MLT and DZN in corn oil vehicle were oral administered. Body and organs weights, plasma and brain cholinesterase activities, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, histopathological changes in liver and kidney, and some parameters of the immune function, such as leukocyte formula, spleen weight and cellularity, spleen lymphocytes proliferation in response to concanavalin A (Con A) were investigated; the potential oxidative stress (malondialdehyde in plasma and brain, and blood catalase activity) was also evaluated. No clinical toxicity signs attributed to pesticides were noted; no significant changes in the organ weights have been found. Body weight tends slightly to increase, predominantly in DZN treated rats. The results suggest that plasma cholinesterase is more susceptible than brain cholinesterase to the inhibitory effect of DZN and MLT. Other serum biochemical parameters showed no significant difference. DZN produced a marked increase of the number of spleen lymphocytes without a significant gain of the relative spleen weight. The both pesticides produced an increase of the number of mononuclear cells÷weight spleen. The splenic lymphocyte proliferation has not been influenced by MLT or DZN treatment. Histopathological observations identified some changes (vasodilatation, microvacuoles, and granular dystrophy) in the liver, with MLT, inducing macrovacuolar steatosis. The study indicates that repeated exposure, at subclinical doses, to organophosphorus MLT and DZN causes some biochemical, histopathological and immune alterations in rats.

  18. Confirmed organophosphorus and carbamate pesticide poisonings in South African wildlife (2009–2014

    Directory of Open Access Journals (Sweden)

    Christo J. Botha

    2015-03-01

    Full Text Available During a six-year period (from January 2009 to December 2014, specimens collected from 344 cases of suspected organophosphorus and carbamate pesticide poisonings in wildlife, including birds, were submitted to the Toxicology Laboratory (ARC-OVI for analysis. A positive diagnosis was made in 135 (39% of these cases. The majority of cases were from birds, which included Cape vultures (Gyps coprotheres and African white-backed vultures (Gyps africanus and bateleur eagles (Terathopius ecaudatus. In one incident 49 vultures were killed when a farmer intentionally laced carcasses with carbofuran in an attempt to control jackal predation. There were 22 incidents of poisoning in helmeted guineafowl (Numida meleagris. On nine different occasions blue cranes (Anthropoides paradiseus were poisoned, in one incident 14 birds were reported to have been killed. Over the period of investigation, there were 20 cases of poisoning involving mammalian species, the majority being vervet monkeys (Chlorocebus pygerythrus. The carbamate pesticides were responsible for 57 incidents of poisoning. Aldicarb, carbofuran and methomyl were detected in 26, 18 and 12 cases respectively. The majority of organophosphorus pesticide poisonings were caused by diazinon (n = 19, monocrotophos (n = 13 and methamidophos (n = 10.

  19. Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

    Directory of Open Access Journals (Sweden)

    Korrapati Kotinagu

    2015-04-01

    Full Text Available Aim: The present study was conducted to find the organochlorine pesticide (OCP and organophosphorus pesticide (OPP residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077. Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167. The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX.

  20. Separating esterase targets of organophosphorus compounds in the brain by preparative chromatography.

    Science.gov (United States)

    Mangas, I; Vilanova, E; Benabent, M; Estévez, J

    2014-02-10

    Low level exposure to organophosphorus esters (OPs) may cause long-term neurological effects and affect specific cognition domains in experimental animals and humans. Action on known targets cannot explain most of these effects by. Soluble carboxylesterases (EC 3.1.1.1) of chicken brain have been kinetically discriminated using paraoxon, mipafox and phenylmethyl sulfonylfluoride as inhibitors and phenyl valerate as a substrate. Three different enzymatic components were discriminated and called Eα, Eβ and Eγ. In this work, a fractionation procedure with various steps was developed using protein native separation methods by preparative HPLC. Gel permeation chromatography followed by ion exchange chromatography allowed enriched fractions with different kinetic behaviors. The soluble chicken brain fraction was fractionated, while total esterase activity, proteins and enzymatic components Eα, Eβ and Eγ were monitored in each subfraction. After the analysis, 13 fractions were pooled and conserved. Preincubation of the soluble chicken brain fraction of with the organophosphorus mipafox gave rise to a major change in the ion exchange chromatography profile, but not in the molecular exchanged chromatography profile, which suggest that mipafox permanently modifies the ionic properties of numerous proteins.

  1. Organophosphorus Pesticide Extraction and Cleanup from Soils and Measurement Using GC-NPD

    Institute of Scientific and Technical Information of China (English)

    WANG Li-Gang; JIANG Xin; MAO Ying-Ming; ZHAO Zhen-Hua; BIAN Yong-Rong

    2005-01-01

    The objectives of this study were to optimize instrumental parameters and conditions for analysis of selected organophosphorus pesticides (OPPs) by gas chromatography (GC) with nitrogen-phosphorus detection (NPD) (GC-NPD); to select an appropriate solvent system; to conduct a comparison of sonication and shaking extractions; and to select an appropriate procedure for extracting organophosphorus pesticides from soils. Procedure Ⅰ consisted of n-hexane or petroleum ether together with acetone used as solvents, while Procedure Ⅱ contained several solvents including acetone,methanol, dichloromethane, and n-hexane or petroleum ether. Experimental results indicated that a mixture of petroleum ether/acetone (2:1, v/v) could be used in place of n-hexane/acetone (2:1, v/v) as it was a less expensive solvent system.In addition, shaking under a water bath at 20 ℃ was more effective than sonication. Also, Procedure Ⅰ was more effective,safer, and more timesaving than Procedure Ⅱ. Procedure I was applied to three soil types of different organic matter content, with recoveries of the OPPs from the yellow-brown soils, which had a higher organic matter content, being lower than those from the yellow and red soils.

  2. In vivo tracing of organophosphorus pesticides in cabbage (Brassica parachinensis) and aloe (Barbadensis)

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Junlang; Chen, Guosheng; Zhou, Hong; Xu, Jianqiao; Wang, Fuxin; Zhu, Fang, E-mail: ceszf@mail.sysu.edu.cn; Ouyang, Gangfeng, E-mail: cesoygf@mail.sysu.edu.cn

    2016-04-15

    In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography–mass spectrometry (GC–MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC–MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production. - Highlights: • In vivo SPME was employed to sample organophosphorus pesticides in vegetables. • Uptake and elimination of OPPs were traced in cabbage and aloe. • In vivo tracing of fenthion demonstrated its metabolites could be rather dangerous. • The risks of OPPs were assessed based on the in vivo tracing data.

  3. Susceptibility of Cimex lectularius (Hemiptera: Cimicidae) to pyrethroid insecticides and to insecticidal dusts with or without pyrethroid insecticides.

    Science.gov (United States)

    Anderson, John F; Cowles, Richard S

    2012-10-01

    Relative increases of bed bug, Cimex lectularius L., populations are probably due in large measure to their resistance to pyrethroids, which have been used extensively against urban pests. A Connecticut population of bed bugs was assessed for sensitivity to pyrethroids and exposed to commonly-used commercial insecticides applied to various substrates on which the residues were allowed to age for 0-24 wk. Type I and type II pyrethroids differed in toxicity when applied at a high dosage (1 microg) per bed bug. Some type II pyrethroids (cyfluthrin, lambda-cyhalothrin, cis-cypermethrin, and deltamethrin) caused > 80% mortality, whereas exposure to type I pyrethroids caused 0.95) an exponential rise to a maximum model from which the survival half-life (S1/2) was calculated directly. Tempo Dust (Bayer Environmental Science, Montvale, NJ) killed bed bugs relatively quickly, as did Syloid 244 (Grace Davison, Columbia, MD) and Drione (Bayer Environmental Science, Montvale, NJ) on hardboard and mattress fabric substrates (S1/2 < 1 d); DeltaDust (Bayer Environmental Science, Montvale, NJ) provided a relatively slow kill (S1/2 approximately equal to 3.5 d). The sprayable pyrethroids, Cyonara 9.7 (Insecticide Control solutions, Pasadena, TX) and D-Force HPX Aerosol 0.06% (Waterbury Companies, Waterbury, CT), displayed reduced residual toxicity as they aged; the mortality was < 50% on some substrates after 4 d. Desiccant dusts, with their physical mode of action and long residual activity, appear to be superior to sprayable pyrethroid products for killing bed bugs.

  4. Acute pancreatitis

    Science.gov (United States)

    ... its blood vessels. This problem is called acute pancreatitis. Acute pancreatitis affects men more often than women. Certain ... pancreatitis; Pancreas - inflammation Images Digestive system Endocrine glands Pancreatitis, acute - CT scan Pancreatitis - series References Forsmark CE. Pancreatitis. ...

  5. Cystitis - acute

    Science.gov (United States)

    Uncomplicated urinary tract infection; UTI - acute cystitis; Acute bladder infection; Acute bacterial cystitis ... cause. Menopause also increases the risk for a urinary tract infection. The following also increase your chances of having ...

  6. Insecticides induced biochemical changes in freshwater microalga Chlamydomonas mexicana.

    Science.gov (United States)

    Kumar, Muthukannan Satheesh; Kabra, Akhil N; Min, Booki; El-Dalatony, Marwa M; Xiong, Jiuqiang; Thajuddin, Nooruddin; Lee, Dae Sung; Jeon, Byong-Hun

    2016-01-01

    The effect of insecticides (acephate and imidacloprid) on a freshwater microalga Chlamydomonas mexicana was investigated with respect to photosynthetic pigments, carbohydrate and protein contents, fatty acids composition and induction of stress indicators including proline, superoxide dismutase (SOD) and catalase (CAT). C. mexicana was cultivated with 1, 5, 10, 15, 20 and 25 mg L(-1) of acephate and imidacloprid. The microalga growth increased with increasing concentrations of both insecticides up to 15 mg L(-1), beyond which the growth declined compared to control condition (without insecticides). C. mexicana cultivated with 15 mg L(-1) of both insecticides for 12 days was used for further analysis. The accumulation of photosynthetic pigments (chlorophyll and carotenoids), carbohydrates and protein was decreased in the presence of both insecticides. Acephate and imidacloprid induced the activities of superoxide dismutase (SOD) and catalase (CAT) and increased the concentration of proline in the microalga, which play a defensive role against various environmental stresses. Fatty acid analysis revealed that the fraction of polyunsaturated fatty acids decreased on exposure to both insecticides. C. mexicana also promoted 25 and 21% removal of acephate and imidacloprid, respectively. The biochemical changes in C. mexicana on exposure to acephate and imidacloprid indicate that the microalga undergoes an adaptive change in response to the insecticide-induced oxidative stress.

  7. Energetic cost of insecticide resistance in Culex pipiens mosquitoes.

    Science.gov (United States)

    Rivero, A; Magaud, A; Nicot, A; Vézilier, J

    2011-05-01

    The extensive use of insecticides to control vector populations has lead to the widespread development of different mechanisms of insecticide resistance. Mutations that confer insecticide resistance are often associated to fitness costs that prevent them from spreading to fixation. In vectors, such fitness costs include reductions in preimaginal survival, adult size, longevity, and fecundity. The most commonly invoked explanation for the nature of such pleiotropic effects of insecticide resistance is the existence of resource-based trade-offs. According to this hypothesis, insecticide resistance would deplete the energetic stores of vectors, reducing the energy available for other biological functions and generating trade-offs between insecticide resistance and key life history traits. Here we test this hypothesis by quantifying the energetic resources (lipids, glycogen, and glucose) of larvae and adult females of the mosquito Culex pipiens L. resistant to insecticides through two different mechanisms: esterase overproduction and acetylcholinesterase modification. We find that, as expected from trade-off theory, insecticide resistant mosquitoes through the overproduction of esterases contain on average 30% less energetic reserves than their susceptible counterparts. Acetylcholinesterase-modified mosquitoes, however, also showed a significant reduction in energetic resources (20% less). We suggest that, in acetylcholinesterase-modified mosquitoes, resource depletion may not be the result of resource-based trade-offs but a consequence of the hyperactivation of the nervous system. We argue that these results not only provide a mechanistic explanation for the negative pleiotropic effects of insecticide resistance on mosquito life history traits but also can have a direct effect on the development of parasites that depend on the vector's energetic reserves to fulfil their own metabolic needs.

  8. Induced tolerance from a sublethal insecticide leads to cross-tolerance to other insecticides.

    Science.gov (United States)

    Hua, Jessica; Jones, Devin K; Relyea, Rick A

    2014-04-01

    As global pesticide use increases, the ability to rapidly respond to pesticides by increasing tolerance has important implications for the persistence of nontarget organisms. A recent study of larval amphibians discovered that increased tolerance can be induced by an early exposure to low concentrations of a pesticide. Since natural systems are often exposed to a variety of pesticides that vary in mode of action, we need to know whether the induction of increased tolerance to one pesticide confers increased tolerance to other pesticides. Using larval wood frogs (Lithobates sylvaticus), we investigated whether induction of increased tolerance to the insecticide carbaryl (AChE-inhibitor) can induce increased tolerance to other insecticides that have the same mode of action (chlorpyrifos, malathion) or a different mode of action (Na(+)channel-interfering insecticides; permethrin, cypermethrin). We found that embryonic exposure to sublethal concentrations of carbaryl induced higher tolerance to carbaryl and increased cross-tolerance to malathion and cypermethrin but not to chlorpyrifos or permethrin. In one case, the embryonic exposure to carbaryl induced tolerance in a nonlinear pattern (hormesis). These results demonstrate that that the newly discovered phenomenon of induced tolerance also provides induced cross-tolerance that is not restricted to pesticides with the same mode of action.

  9. Synthetic and structure-activity relationship of insecticidal bufadienolides.

    Science.gov (United States)

    Hidayat, Ace Tatang; Zainuddin, Achmad; Dono, Danar; Hermawan, Wawan; Hayashi, Hideo; Supratman, Unang

    2014-07-01

    A new synthetic analog of bufadienolide, methyl isobryophyllinate A (1), and a known synthetic analog, methyl isobersaldegenate-1,3,5-orthoacetate (2), were obtained by methanolysis of bryophyllin A (3) and bersaldegenin-1,3,5-orthoacetate (5) in basic solution. Structure-insecticidal activity relationship studies revealed both orthoacetate and alpha-pyrone moieties seemed to be essential structural elements for exhibiting insecticidal activity, whereas oxygenated substituents in the C ring enhanced the insecticidal activity against the third instar larvae of silkworm (Bombyx mori).

  10. Insecticidal Activity of Cyanohydrin and Monoterpenoid Compounds

    Directory of Open Access Journals (Sweden)

    Joel R. Coats

    2000-04-01

    Full Text Available The insecticidal activities of several cyanohydrins, cyanohydrin esters and monoterpenoid esters (including three monoterpenoid esters of a cyanohydrin were evaluated. Topical toxicity to Musca domestica L. adults was examined, and testing of many compounds at 100 mg/fly resulted in 100% mortality. Topical LD50 values of four compounds for M. domestica were calculated. Testing of many of the reported compounds to brine shrimp (Artemia franciscana Kellog resulted in 100% mortality at 10 ppm, and two compounds caused 100% mortality at 1 ppm. Aquatic LC50 values were calculated for five compounds for larvae of the yellow fever mosquito (Aedes aegypti (L.. Monoterpenoid esters were among the most toxic compounds tested in topical and aquatic bioassays.

  11. Biosensor for Direct Determination of Fenitrothion and EPN Using Recombinant Pseudomonas putida JS444 with Surface Expressed Organophosphorus Hydrolase. 1. Modified Clark Oxygen Electrode

    OpenAIRE

    2006-01-01

    This paper reports a first microbial biosensor for rapid and cost-effective determination of organophosphorus pesticides fenitrothion and EPN. The biosensor consisted of recombinant PNP-degrading/oxidizing bacteria Pseudomonas putida JS444 anchoring and displaying organophosphorus hydrolase (OPH) on its cell surface as biological sensing element and a dissolved oxygen electrode as the transducer. Surface-expressed OPH catalyzed the hydrolysis of fenitrothion and EPN to release 3-methyl-4-nitr...

  12. Simultaneous quantification of the organophosphorus pesticides dimethoate and omethoate in porcine plasma and urine by LC-ESI-MS/MS and flow-injection-ESI-MS/MS.

    Science.gov (United States)

    John, Harald; Eddleston, Michael; Clutton, R Eddie; Worek, Franz; Thiermann, Horst

    2010-05-15

    Dimethoate is an organophosphorus toxicant used in agri- and horticulture as a systemic broad-spectrum insecticide. It also exhibits toxic activity towards mammalian organism provoked by catalytic desulfuration in the liver producing its oxon-derivative omethoate thus inhibiting acetylcholinesterase, initiating cholinergic crisis and ultimately leading to death by respiratory paralysis and cardiovascular collapse. Pharmaco- and toxicokinetic studies in animal models help to broaden basic understanding of medical intervention by antidotes and supportive care. Therefore, we developed and validated a LC-ESI-MS/MS method suitable for the simultaneous, selective, precise (RSD(intra-day) 1-8%; RSD(inter-day) 5-14%), accurate (intra-day: 95-107%; inter-day: 90-115%), and robust quantification of both pesticides from porcine urine and plasma after deproteinization by precipitation and extensive dilution (1:11,250 for plasma and 1:40,000 for urine). Accordingly, lower limits of quantification (0.24-0.49 microg/ml plasma and 0.78-1.56 microg/ml urine) and lower limits of detection (0.12-0.24 microg/ml plasma and 0.39-0.78 microg/ml urine) were equivalent to quite low absolute on-column amounts (1.1-2.1 pg for plasma and 2.0-3.9 pg for urine). The calibration range (0.24-250 microg/ml plasma and 0.78-200 microg/ml urine) was subdivided into two linear ranges (r(2)>or=0.998) each covering nearly two orders of magnitude. The lack of any interfering peak in 6 individual blank specimens from plasma and urine demonstrated the high selectivity of the method. Furthermore, extensive sample dilution causing lowest concentration of potentially interfering matrix ingredients prompted us to develop and validate an additional flow-injection method (FI-ESI-MS/MS). Validation characteristics were as good as for the chromatographic method but sample throughput was enhanced by a factor of 6. Effects on ionization provoked by plasma and urine matrix from 6 individuals as well as in the

  13. Federal Insecticide, Fungicide, and Rodenticide Act Section 18 Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — Section 18 of Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) authorizes EPA to allow an unregistered use of a pesticide for a limited time if EPA...

  14. Fungal infection counters insecticide resistance in African malaria mosquitoes

    NARCIS (Netherlands)

    Farenhorst, M.; Mouatcho, J.C.; Kikankie, C.K.; Brooke, B.D.; Hunt, R.H.; Thomas, M.B.; Koekemoer, L.L.; Knols, B.G.J.; Coetzee, M.

    2009-01-01

    The evolution of insecticide resistance in mosquitoes is threatening the effectiveness and sustainability of malaria control programs in various parts of the world. Through their unique mode of action, entomopathogenic fungi provide promising alternatives to chemical control. However, potential inte

  15. Insect P450 inhibitors and insecticides: challenges and opportunities.

    Science.gov (United States)

    Feyereisen, René

    2015-06-01

    P450 enzymes are encoded by a large number of genes in insects, often over a hundred. They play important roles in insecticide metabolism and resistance, and growing numbers of P450 enzymes are now known to catalyse important physiological reactions, such as hormone metabolism or cuticular hydrocarbon synthesis. Ways to inhibit P450 enzymes specifically or less specifically are well understood, as P450 inhibitors are found as drugs, as fungicides, as plant growth regulators and as insecticide synergists. Yet there are no P450 inhibitors as insecticides on the market. As new modes of action are constantly needed to support insecticide resistance management, P450 inhibitors should be considered because of their high potential for insect selectivity, their well-known mechanisms of action and the increasing ease of rational design and testing.

  16. Design, Synthesis and Insecticidal Activity of Novel Phenylurea Derivatives

    Directory of Open Access Journals (Sweden)

    Jialong Sun

    2015-03-01

    Full Text Available A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity.

  17. Design, synthesis and insecticidal activity of novel phenylurea derivatives.

    Science.gov (United States)

    Sun, Jialong; Zhou, Yuanming

    2015-03-19

    A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity.

  18. A Survey of Determination for Organophosphorus Pesticide Residue in Agricultural Products

    Directory of Open Access Journals (Sweden)

    Wen Li

    2013-04-01

    Full Text Available In order to find a fast, high efficient determination method of Organophosphorus Pesticides (OPPs residue because OPPs widely used in crops pest control fields in China are causing fearful risks for environment as well as animals and human health, traditional and advanced determination methods were discussed in the study. Based on the spectrum analysis technology combined colorimetric OPPs residue detection experiments in leafy vegetables showed that the absorbance of color reaction between OPPs residues and suitable colorimetric reagents can be distinguished in ppm level of OPPs residues. The detection limit of chlorpyrifos after color reaction with 0.5% Pbcl2 in acetic acid solution is 0.5 ppm. The conclusion was drawn that the detection technologies were diversified, however, a simple, efficient, rapid and nondestructive detection method is lacking and the spectrum analysis technology combined colorimetric can be a new fast and efficient determination method in the future.

  19. A review on the molecular mechanisms involved in insulin resistance induced by organophosphorus pesticides.

    Science.gov (United States)

    Lasram, Mohamed Montassar; Dhouib, Ines Bini; Annabi, Alya; El Fazaa, Saloua; Gharbi, Najoua

    2014-08-01

    There is increasing evidence reporting that organophosphorus pesticides (OPs) impair glucose homeostasis and cause insulin resistance and type 2 diabetes. Insulin resistance is a complex metabolic disorder that defies explanation by a single etiological pathway. Formation of advanced glycation end products, accumulation of lipid metabolites, activation of inflammatory pathways and oxidative stress have all been implicated in the pathogenesis of insulin resistance. Ultimately, these molecular processes activate a series of stress pathways involving a family of serine kinases, which in turn have a negative effect on insulin signaling. Experimental and clinical data suggest an association between these molecular mechanisms and OPs compounds. It was first reported that OPs induce hyperglycemia. Then a concomitant increase of blood glucose and insulin was pointed out. For some years only, we have begun to understand that OPs promote insulin resistance and increase the risk of type 2 diabetes. Overall, this review outlines various mechanisms that lead to the development of insulin resistance by OPs exposure.

  20. Influence of organophosphorus pesticides on peroxidase and chlorination activity of human myeloperoxidase.

    Science.gov (United States)

    Lazarević-Pašti, Tamara; Momić, Tatjana; Radojević, Miloš M; Vasić, Vesna

    2013-09-01

    Inhibitory effects of five organophosphorus pesticides (diazinon, malathion, chlorpyrifos, azinphos-methyl and phorate) and their oxo-analogs on human myeloperoxidase (MPO) activity were investigated. While inspecting separately peroxidase and chlorination activity, it was observed that investigated OPs affect peroxidase activity, but not chlorination activity. Among investigated pesticides, malathion and malaoxon have showed the highest power to inhibit MPO peroxidase activity with IC50 values of the order of 3×10(-7) and 5×10(-9) M, respectively. It was proposed that inhibition trend is rendered by molecular structure which invokes steric hindrance for OPs interaction with MPO active center responsible for peroxidase activity. In addition, it was concluded that physiological function of MPO is not affected by any of the investigated OPs.

  1. Removal of acetic acid from simulated hemicellulosic hydrolysates by emulsion liquid membrane with organophosphorus extractants.

    Science.gov (United States)

    Lee, Sang Cheol

    2015-09-01

    Selective removal of acetic acid from simulated hemicellulosic hydrolysates containing xylose and sulfuric acid was attempted in a batch emulsion liquid membrane (ELM) system with organophosphorus extractants. Various experimental variables were used to develop a more energy-efficient ELM process. Total operation time of an ELM run with a very small quantity of trioctylphosphine oxide as the extractant was reduced to about a third of those required to attain almost the same extraction efficiency as obtained in previous ELM works without any extractant. Under specific conditions, acetic acid was selectively separated with a high degree of extraction and insignificant loss of xylose, and its purity and enrichment ratio in the stripping phase were higher than 92% and 6, respectively. Also, reused organic membrane solutions exhibited the extraction efficiency as high as fresh organic solutions did. These results showed that the current ELM process would be quite practical.

  2. Organophosphorus flame retardants and plasticizers: sources, occurrence, toxicity and human exposure.

    Science.gov (United States)

    Wei, Gao-Ling; Li, Ding-Qiang; Zhuo, Mu-Ning; Liao, Yi-Shan; Xie, Zhen-Yue; Guo, Tai-Long; Li, Jun-Jie; Zhang, Si-Yi; Liang, Zhi-Quan

    2015-01-01

    Due to the restricted use and ban of brominated flame retardants, organophosphorus compounds (OPs), extensively used as flame retardants and plasticizers, are ubiquitous in various environmental compartments worldwide. The present study shows that the release of OPs from a wide variety of commercial products and wastewater discharge might be considered as primary emission sources and that high potential of long-range atmospheric transport and persistence of OPs would be responsible for their presence in various matrices on a global scale. The occurrence and environmental behaviors of OPs in diverse matrices (e.g., dust, air, water, sediment, soil and biota) are reviewed. Human exposures to OPs via dermal contact, dust ingestion, inhalation and dietary intake are comprehensively evaluated. Finally, this study identifies gaps in the existing issues and generates a future agenda for the emerging contaminants OPs.

  3. Acute Bronchitis

    Science.gov (United States)

    ... Smoking also slows down the healing process. Acute bronchitis treatment Most cases of acute bronchitis can be treated at home.Drink fluids, but ... bronchial tree. Your doctor will decide if this treatment is right for you. Living with acute bronchitis Most cases of acute bronchitis go away on ...

  4. Organochlorine insecticide poisoning in Golden Langurs Trachypithecus geei

    Directory of Open Access Journals (Sweden)

    D.C. Pathak

    2011-07-01

    Full Text Available Organochlorine insecticide poisoning was recorded in three Golden Langurs (Trachypithecus geei in Chakrashila Wildlife Sanctuary (CWS in Kokrajhar district of Assam during the month of December, 2008. The poisoning was due to prolonged ingestion of rubber plant leaves sprayed with the insecticide in a rubber plantation adjacent to the sanctuary. Though no specific gross lesions were observed, histopathologically, centilobular hepatic necrosis, mild renal degeneration, necrotic enteritis, pulmonary congestion and neuronal degeneration were recorded in all three animals.

  5. Mechanism of Insect Resistance to the Microbial Insecticide Bacillus thuringiensis

    Science.gov (United States)

    van Rie, J.; McGaughey, W. H.; Johnson, D. E.; Barnett, B. D.; van Mellaert, H.

    1990-01-01

    Receptor binding studies show that resistance of a laboratory-selected Plodia interpunctella strain to a Bacillus thuringiensis insecticidal crystal protein (ICP) is correlated with a 50-fold reduction in affinity of the membrane receptor for this protein. The strain is sensitive to a second type of ICP that apparently recognizes a different receptor. Understanding the mechanism of resistance will provide strategies to prevent or delay resistance and hence prolong the usefulness of B. thuringiensis ICPs as environmentally safe insecticides.

  6. Impact of triazophos insecticide on paddy soil environment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A laboratory incubation study was carried out to elucidate the dynamic response of insecticide (triazophos) on a paddy field soil health under controlled moisture (flooded soil) and temperature (25℃).The insecticide was applied at five levels that were 0.0 (control),0.5 field rate (FR),1.0 FR,5.0 FR,and 10.0 FR,where FR was 1500 ml/hm2,and the parameters were studied at 1,4,7,14,and 21days after treatments' addition.The electron transport system (ETS)/dehydrogenase activity exhibited a negative correlation with insecticide concentrations,and the activity affected adversely as the concentration increased.The higher doses of 5 and 10 field rates significantly reduced the ETS activity,while lower rates failed to produce any significant inhibiting effect against the control.The toxicity of insecticide decreased towards decreasing the ETS activity with the advancement of incubation period.The insecticide caused an improvement in the soil phenol content and it increased with increasing concentration of insecticide.The insecticide incorporation applied at various concentrations did not produce any significant change in soil protein content and it remained stable throughout the incubation period of 21 - days.The response of biomass phospholipid content was nearly similar to ETS activity.The phospholipid content was decreased with the addition of insecticide and the toxicity was in the order:10 FR (field rate) > 5 FR > 1.0 FR > 0.5 FR > control and it also decreased with incubation period.

  7. Engineering and introduction of de novo disulphide bridges in organophosphorus hydrolase enzyme for thermostability improvement

    Indian Academy of Sciences (India)

    GHOLAMREZA FARNOOSH; KHOSRO KHAJEH; ALI MOHAMMAD LATIFI; HOSSEIN AGHAMOLLAEI

    2016-12-01

    The organophosphorus hydrolase (OPH) has been used to degrade organophosphorus chemicals, as one of the mostfrequently used decontamination methods. Under chemical and thermal denaturing conditions, the enzyme has beenshown to unfold. To utilize this enzyme in various applications, the thermal stability is of importance. The engineeringof de novo disulphide bridges has been explored as a means to increase the thermal stability of enzymes in the rationalmethod of protein engineering. In this study, Disulphide by Design software, homology modelling and moleculardynamics simulations were used to select appropriate amino acid pairs for the introduction of disulphide bridge toimprove protein thermostability. The thermostability of the wild-type and three selected mutant enzymes wereevaluated by half-life, ΔG inactivation (ΔGi) and structural studies (fluorescence and far-UV CD analysis). Dataanalysis showed that half-life of A204C/T234C and T128C/E153C mutants were increased up to 4 and 24 min,respectively; however, for the G74C/A78C mutant, the half-life was decreased up to 9 min. For the T128C/E124Cmutant, both thermal stability and Catalytic efficiency (kcat) were also increased. The half-life and ΔGi results werecorrelated to the obtained information from structural studies by circular dichroism (CD) spectrometry and extrinsicfluorescence experiments; as rigidity increased in A204C/T2234C and T128C/E153C mutants, half-life and ΔGi alsoincreased. For G74C/A78C mutant, these parameters decreased due to its higher flexibility. The results weresubmitted a strong evidence for the possibility to improve the thermostability of OPH enzyme by introducing adisulphide bridge after bioinformatics design, even though this design would not be always successful.

  8. Effects of the synthetic pyrethroid insecticide, permethrin, on two estuarine fish species.

    Science.gov (United States)

    Parent, Lindsey M; Delorenzo, Marie E; Fulton, Michael H

    2011-01-01

    Limited toxicity data are available for estuarine and marine species and the widely used pyrethroid insecticide, permethrin. This study determined acute effects of permethrin on survival, lipid peroxidation, acetylcholinesterase activity, and splenocyte proliferation for two fish species found in South Carolina estuaries; juvenile red drum (Sciaenops ocellatus) and adult mummichog (Fundulus heteroclitus). Juvenile S. ocellatus were significantly more sensitive than adult F. heteroclitus to permethrin exposure, with a 96-h LC50 value of 8 μg/L determined for red drum compared to 23 μg/L for mummichog. Lipid peroxidation activity of the liver increased in permethrin-treated fish compared to control animals after 24 h and decreased after 96 h. Permethrin had no effect on acetylcholinesterase activity of the brain at the concentrations tested. Permethrin exposure significantly inhibited splenocyte proliferation, indicating an immunosuppressive effect. Most of the effects of permethrin on fish cellular stress enzymes and survival occurred at concentrations much higher than those typically measured in the environment. However, inhibition of splenocyte proliferation in juvenile red drum occurred at approximately twice that of measured permethrin concentrations in surface water. These findings may prove useful to the future management and regulation of pyrethroid insecticide use near estuarine habitats.

  9. Insecticidal action of sodium anacardate from Brazilian cashew nut shell liquid against Aedes aegypti.

    Science.gov (United States)

    Farias, Davi F; Cavalheiro, Mariana G; Viana, Sayonara M; De Lima, Glauber P G; da Rocha-Bezerra, Lady Clarissa B; Ricardo, Nágila M P S; Carvalho, Ana F U

    2009-09-01

    Aedes aegypti is the major vector of 1 of the most concerning arboviruses of the world, the dengue fever. The only effective way of reducing the incidence of dengue fever is to control the vector mosquito, mainly by application of insecticides to its breeding places. This study was aimed at assessing the insecticidal activity of sodium anacardate, isolated from Brazilian cashew nut shell liquid (CNSL), against the eggs, 3rd instars or pupae of Ae. aegypti. In addition, the acute toxicity of sodium anacardate to mice was also investigated. Sodium anacardate showed toxicity against Ae. aegypti eggs (median effective concentration [EC50] = 162.93 +/- 29.93 microg/ml), larvae (median lethal concentration [LC50] = 55.47 +/- 3.0 microg/ml) and pupae (LC50 = 369.78 - 52.30 microg/ml). On the other hand, even at high dose (0.3 g/kg body weight), this compound did not cause any adverse effects on mice, suggesting that this compound is safe to mammals. Therefore, sodium anacardate may be a viable low-cost alternative to help combat Ae. aegypti.

  10. Interactive effects of mosquito control insecticide toxicity, hypoxia, and increased carbon dioxide on larval and juvenile eastern oysters and hard clams.

    Science.gov (United States)

    Garcia, R N; Chung, K W; Key, P B; Burnett, L E; Coen, L D; Delorenzo, M E

    2014-04-01

    Mosquito control insecticide use in the coastal zone coincides with the habitat and mariculture operations of commercially and ecologically important shellfish species. Few data are available regarding insecticide toxicity to shellfish early life stages, and potential interactions with abiotic stressors, such as low oxygen and increased CO2 (low pH), are less understood. Toxicity was assessed at 4 and 21 days for larval and juvenile stages of the Eastern oyster, Crassostrea virginica, and the hard clam, Mercenaria mercenaria, using two pyrethroids (resmethrin and permethrin), an organophosphate (naled), and a juvenile growth hormone mimic (methoprene). Acute toxicity (4-day LC50) values ranged from 1.59 to >10 mg/L. Overall, clams were more susceptible to mosquito control insecticides than oysters. Naled was the most toxic compound in oyster larvae, whereas resmethrin was the most toxic compound in clam larvae. Mortality for both species generally increased with chronic insecticide exposure (21-day LC50 values ranged from 0.60 to 9.49 mg/L). Insecticide exposure also caused sublethal effects, including decreased swimming activity after 4 days in larval oysters (4-day EC50 values of 0.60 to 2.33 mg/L) and decreased growth (shell area and weight) in juvenile clams and oysters after 21 days (detected at concentrations ranging from 0.625 to 10 mg/L). Hypoxia, hypercapnia, and a combination of hypoxia and hypercapnia caused mortality in larval clams and increased resmethrin toxicity. These data will benefit both shellfish mariculture operations and environmental resource agencies as they manage the use of mosquito control insecticides near coastal ecosystems.

  11. Neuroprotection against diisopropylfluorophosphate in acute hippocampal slices

    Science.gov (United States)

    Ferchmin, P. A.; Pérez, Dinely; Cuadrado, Brenda L.; Carrasco, Marimée; Martins, Antonio H.; Eterović, Vesna A.

    2015-01-01

    Diisopropylfluorophosphate (DFP) is an irreversible inhibitor of acetylcholine esterase (AChE) and a surrogate of the organophosphorus (OP) nerve agent sarin. The neurotoxicity of DFP was assessed as a reduction of population spike (PS) area elicited by synaptic stimulation in acute hippocampal slices. Two classical antidotes, atropine, and pralidoxime, and two novel antidotes, 4R-cembranotriene-diol (4R) and a caspase 9 inhibitor, were tested. Atropine, pralidoxime, and 4R significantly protected when applied 30 min after DFP. The caspase inhibitor was neuroprotective when applied 5–10 min before or after DFP, suggesting that early synaptic apoptosis is responsible for the loss of PSs. It is likely that apoptosis starts at the synapses and, if antidotes are not applied, descends to the cell bodies, causing death. The acute slice is a reliable tool for mechanistic studies, and the assessment of neurotoxicity and neuroprotection with PS areas is, in general, pharmacologically congruent with in vivo results and predicts the effect of drugs in vivo. 4R was first found to be neuroprotective in slices and later we demonstrated that 4R is neuroprotective in vivo. The mechanism of neurotoxicity of OPs is not well understood, and there is a need for novel antidotes that could be discovered using acute slices. PMID:26438150

  12. Using Luseweilei insecticide to control Dendrolimus superans T.

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Luseweilei is an easily-bursted microcapsule insecticide. A test of effectiveness of the insecticide to control the larvae of Dendrolimus superans T. was carried out in larch forest in Baoan Forest Farm of Nehe City, Heilongjiang Province, in April 2001. The solutions of different concentrations (1:150, 1:250, 1:350, and 1:450 Luseweilei : water) were sprayed on the larch trunk before the overwintering larvae climbing on trees and the spraying lengths (height) designed were 1.0, 2.5, and 3.5 m high from ground. The control result showed that spraying 150-, 250-, and 350-fold solutions of the insecticide all produced a good control result, with a mortality rate of 97%, but the 450-fold solution only produced 70% mortality. It is concluded that this insecticide can be used as a kind of good insecticide to control the overwintering larvae of D. superans in spring. Spraying 350-fold solution of easy-burst microcapsule insecticide and one meter spraying length are recommended for the future application..

  13. Profile of the population use of household insecticides against mosquitoes

    Directory of Open Access Journals (Sweden)

    Luzilene Barbosa Oliveira

    2015-11-01

    Full Text Available This study described the use of household insecticides in Picos (Piauí, Brazil, identify which are the most used types of insecticides and describes the incidence of poisoning and environmental awareness of the population. After home visits (n = 700, it was seen that the majority of respondents was represented by women (75%, with 31-55 years-old (49%, incomplete primary education (38.1% and income between 1-2 earnings (64%. Most homes have between 1-3 residents (48%, 85% of the persons use insecticides mainly chosen in TV and radio and only 54% of them read the label before employing the product. The most used form of presentation is the aerosol (70.7%. Majority (79% recognizes that insecticides are harmful to health, but 74% do not use any Personal Protective Equipment (PPE. Symptoms of toxicity were reported by 27% of people interviewed. Two women reported irritation, dizziness and respiratory problems and need for medical intervention and hospitalization. All interviewed discard the package as regular trash, since Picos does not has selective collection. In conclusion, most people use insecticides, know about the individual and collective risks to which they are exposed but do not use PPE, though they believe insecticides are toxic. It was noted that acquisition of knowledge does not necessarily result in behavioral changes, since learning does not translate into appropriate preventive attitudes and practices, emphasizing the requirement for awareness campaigns about toxicity and environmental risks, preparation of professionals and surveillance policy against indiscriminate sale.

  14. Impact of some selected insecticides application on soil microbial respiration.

    Science.gov (United States)

    Latif, M A; Razzaque, M A; Rahman, M M

    2008-08-15

    The aim of present study was to investigate the impact of selected insecticides used for controlling brinjal shoot and fruit borer on soil microorganisms and to find out the insecticides or nontoxic to soil microorganism the impact of nine selected insecticides on soil microbial respiration was studied in the laboratory. After injection of different insecticides solutions, the soil was incubated in the laboratory at room temperature for 32 days. The amount of CO2 evolved due to soil microbial respiration was determined at 2, 4, 8, 16, 24 and 32 days of incubation. Flubendiamide, nimbicidine, lambda-cyhalothrin, abamectin and thiodicarb had stimulatory effect on microbial respiration during the initial period of incubation. Chlorpyriphos, cartap and carbosulfan had inhibitory effect on microbial respiration and cypermethrin had no remarkable effect during the early stage of incubation. The negative effect of chlorpyriphos, cartap and carbosulfan was temporary, which was disappeared after 4 days of insecticides application. No effect of the selected insecticides on soil microorganisms was observed after 24 or 32 days of incubation.

  15. Design, synthesis and insecticidal evaluation of aryloxy dihalopropene derivatives.

    Science.gov (United States)

    Yang, Ji-Chun; Li, Miao; Wu, Qiao; Liu, Chang-Ling; Chang, Xiu-Hui

    2016-02-01

    Plutella xylostella (P. xylostella) is a highly migratory, cosmopolitan species and one of the most important pest of cruciferous crops worldwide. Pyridalyl as a novel class of insecticides has good efficacy against P. xylostella. On the basis of the commercial insecticide pyridalyl, a series of new aryloxy dihalopropene derivatives were designed and synthesized by using Intermediate Derivatization Methods. Their chemical structures were confirmed by (1)H NMR, high-resolution mass spectrum (HRMS), and single-crystal X-ray diffraction analysis. The insecticidal activities of the new compounds against P. xylostella were evaluated. The results of bioassays indicated that most of the compounds showed moderate to high activities at the tested concentration, especially compounds 10e and 10g displayed more than 75% insecticidal activity against P. xylostella at 6.25mg/L, while pyridalyl showed 50% insecticidal activity at the same concentration. The field trials result of the insecticidal activities showed that compound 10e as a 10% emulsifiable concentrate (EC) was effective in the control of P. xylostella at 75-150g a.i./ha, and the mortality of P. xylostella for treatment with compound 10e at 75g a.i./ha was equivalent to pyridalyl at 105g a.i./ha.

  16. Sublethal and transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae) : toxicity of insecticides to Trichogramma galloi.

    Science.gov (United States)

    Costa, Mariana Abreu; Moscardini, Valéria Fonseca; da Costa Gontijo, Pablo; Carvalho, Geraldo Andrade; de Oliveira, Rodrigo Lopes; de Oliveira, Harley Nonato

    2014-10-01

    This study assessed the transgenerational effects of insecticides in developing Trichogramma galloi (Hymenoptera: Trichogrammatidae). Laboratory bioassays were performed in which five insecticides were sprayed on egg-larval, pre-pupal and pupal stages of the parasitoid. The interaction between insecticides and development stages of the parasitoid was not significant for the rate of F0 emergence. All insecticides significantly reduced the emergence of wasps, with the lowest emergence observed when they were applied to the pupal stage. For the sex ratio, only spinosad applied to the pre-pupal stage and triflumuron applied on the egg-larval and pre-pupal stages did not differ from the controls. Triflumuron applied to pre-pupae did not lead to any difference in the parasitism rate of the treated generation (F0) when compared to the control. There were no significant differences among survival curves for females of F0 when all insecticides were sprayed on the egg-larval stage. Both concentrations of lambda-cyhalothrin + thiamethoxam reduced female pre-pupal survival, and all treatments reduced female pupal survival. In addition, we observed a transgenerational effect of the insecticides on emergence and sex ratio of next generation (F1). Lambda-cyhalothrin + thiamethoxam (Min) applied to the pre-pupae and pupae, the maximum rate of the same insecticides applied to the egg-larvae and pre-pupae, and spinosad applied to pre-pupae all significantly reduced the adults emergence of T. galloi F1 generation. Only triflumuron did not alter the F1 sex ratio. These bioassays provide a basis for better understanding the effects of insecticide use on beneficial parasitoids.

  17. Improvement in organophosphorus hydrolase activity of cell surface-engineered yeast strain using Flo1p anchor system.

    Science.gov (United States)

    Fukuda, Takeshi; Tsuchiyama, Kouta; Makishima, Hirokazu; Takayama, Katsumi; Mulchandani, Ashok; Kuroda, Kouichi; Ueda, Mitsuyoshi; Suye, Shin-ichiro

    2010-05-01

    Organophosphorus hydrolase (OPH) hydrolyzes organophosphorus esters. We constructed the yeast-displayed OPH using Flo1p anchor system. In this system, the N-terminal region of the protein was fused to Flo1p and the fusion protein was displayed on the cell surface. Hydrolytic reactions with paraoxon were carried out during 24 h of incubation of OPH-displaying cells at 30 degrees C. p-Nitrophenol produced in the reaction mixture was detected by HPLC. The strain with highest activity showed 8-fold greater OPH activity compared with cells engineered using glycosylphosphatidylinositol anchor system, and showed 20-fold greater activity than Escherichia coli using the ice nucleation protein anchor system. These results indicate that Flo1p anchor system is suitable for display of OPH in the cell surface-expression systems.

  18. Analogues with fluorescent leaving groups for screening and selection of enzymes that efficiently hydrolyze organophosphorus nerve agents.

    Science.gov (United States)

    Briseño-Roa, Luis; Hill, Jim; Notman, Stuart; Sellers, David; Smith, Andy P; Timperley, Christopher M; Wetherell, Janet; Williams, Nichola H; Williams, Gareth R; Fersht, Alan R; Griffiths, Andrew D

    2006-01-12

    Enzymes that efficiently hydrolyze highly toxic organophosphorus nerve agents could potentially be used as medical countermeasures. As sufficiently active enzymes are currently unknown, we synthesized twelve fluorogenic analogues of organophosphorus nerve agents with the 3-chloro-7-oxy-4-methylcoumarin leaving group as probes for high-throughput enzyme screening. This set included analogues of the pesticides paraoxon, parathion, and dimefox, and the nerve agents DFP, tabun, sarin, cyclosarin, soman, VX, and Russian-VX. Data from inhibition of acetylcholinesterase, in vivo toxicity tests of a representative analogue (cyclosarin), and kinetic studies with phosphotriesterase (PTE) from Pseudomonas diminuta, and a mammalian serum paraoxonase (PON1), confirmed that the analogues mimic the parent nerve agents effectively. They are suitable tools for high-throughput screens for the directed evolution of efficient nerve agent organophosphatases.

  19. Variation in toxicity of a current-use insecticide among resurrected Daphnia pulicaria genotypes.

    Science.gov (United States)

    Simpson, Adam M; Jeyasingh, Punidan D; Belden, Jason B

    2015-04-01

    This study examined how genotypes of Daphnia pulicaria from a single population, separated by thousands of generations of evolution in the wild, differ in their sensitivity to a novel anthropogenic stressor. These genotypes were resurrected from preserved resting eggs isolated from sediments belonging to three time periods: 2002-2008, 1967-1977, and 1301-1646 A.D. Toxicity of the organophosphate insecticide chlorpyrifos was determined through a series of acute toxicity tests. There was a significant dose-response effect in all genotypes studied. Moreover, significant variation in toxicity among genotypes within each time period was detected. Importantly, a significant effect of time period on sensitivity to chlorpyrifos was found. Analysis of the median effect concentrations (EC50s) for genotypes within each time period indicated that the 1301-1646 genotypes were 2.7 times more sensitive than the 1967-1977 genotypes. This trend may be partially explained by microevolutionary shifts in response to cultural eutrophication.

  20. Quantum dot-DNA aptamer conjugates coupled with capillary electrophoresis: A universal strategy for ratiometric detection of organophosphorus pesticides.

    Science.gov (United States)

    Tang, Tingting; Deng, Jingjing; Zhang, Min; Shi, Guoyue; Zhou, Tianshu

    2016-01-01

    Based on the highly sensitivity and stable-fluorescence of water-soluble CdTe/CdS core-shell quantum dots (QDs) with broad-specificity DNA aptamers, a novel ratiometric detection strategy was proposed for the sensitive detection of organophosphorus pesticides by capillary electrophoresis with laser-induced fluorescence (CE-LIF). The as-prepared QDs were first conjugated with the amino-modified oligonucleotide (AMO) by amidation reaction, which is partial complementary to the DNA aptamer of organophosphorus pesticides. Then QD-labeled AMO (QD-AMO) was incubated with the DNA aptamer to form QD-AMO-aptamer duplex. When the target organophosphorus pesticides were added, they could specifically bind the DNA aptamer, leading to the cleavage of QD-AMO-aptamer duplex, accompany with the release of QD-AMO. As a result, the ratio of peak height between QD-AMO and QD-AMO-aptamer duplex changed in the detection process of CE-LIF. This strategy was subsequently applied for the detection of phorate, profenofos, isocarbophos, and omethoate with the detection limits of 0.20, 0.10, 0.17, and 0.23μM, respectively. This is the first report about using QDs as the signal indicators for organophosphorus pesticides detection based on broad-specificity DNA aptamers by CE-LIF, thus contributing to extend the scope of application of QDs in different fields. The proposed method has great potential to be a universal strategy for rapid detection of aptamer-specific small molecule targets by simply changing the types of aptamer sequences.

  1. Overexpression of Human Senescence Marker Protein 30 in Mice Fails to Offer Protection Against Challenge with Organophosphorus Compounds

    Science.gov (United States)

    2011-09-01

    organophosphate poisoning . Proc Natl Acad Sci U S A 104: 13603-13608. 8. Ashani Y, Pistinner S (2004) Estimation of the upper limit of human...life-threatening risk to both soldiers and civilians [1]. Current antidotal regimen for OP poisoning includes anticholinergic drugs to counteract the...Eyer P, Felgenhauer N, Zilker T, Worek F. (2007) Lessons to be learnt from organophosphorus pesticide poisoning for the treatment of nerve agent

  2. Mutagenic and cytotoxic activities of benfuracarb insecticide.

    Science.gov (United States)

    Eren, Yasin; Erdoğmuş, Sevim Feyza; Akyıl, Dilek; Özkara, Arzu

    2016-08-01

    Benfuracarb is a carbamate insecticide used to control insect pests in vegetables and it has anti-acetylcholinesterase activity lower than other carbamates. Cytotoxic effects of benfuracarb were evaluated by using root growth inhibition (EC50), mitotic index (MI), and mitotic phase determinations on the root meristem cells of Allium cepa and mutagenic effects were determined in Salmonella typhymurium Ames test by TA98 and TA100 strains with and without metabolic activation. In Allium test, 1 % DMSO was used as negative control group and 10 ppm MMS was used as positive control group. 75 ppm concentration of benfuracarb was found as EC50. In MI and mitotic phases determination study, 37.5, 75 and 150 ppm doses of benfuracarb were used. Dose-dependent cytotoxic activity was found by root growth inhibition and MI studies. It was identified that mitotic inhibition activity of benfuracarb was higher than 10 ppm MMS. In Ames test, mutagenic activity was not observed and over 200 µg/plate of benfuracarb was determined as cytotoxic to S. typhymurium strains. Benfuracarb can be called as "mitotic inhibitor" but not called as mutagen.

  3. Anaerobic microbial degradation of organochlorine insecticides Aldrin

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, T.C.; Yen, J.H.; Wang, Y.S. [National Taiwan Univ. (Taiwan)

    2004-09-15

    Aldrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-1,4-endo-exo-5,8-dimethanonnaphthalene), a cyclodiene organochlorine insecticide, was banned by nations and classified as B2 carcinogen by United States Environmental Protection Agency (EPA). Because of its chemical stability and lipophilicity, aldrin is regarded as a persistent and recalcitrant compound. Aldrin is easily adsorbed to soil and sediment after spreading to the environments, furthermore, it may be accumulated in animal's tissue or milk and then cause adverse effects by food-chain. The dissipation process of aldrin in environments has continuously been paid much attention by researchers. In general, the dissipation of aldrin has been thought as relating to three mechanisms: photo-degradation, chemical hydrolysis, and microbial degradation. And it has been well known that microbial degradation is the most important agent for breakdown of organochlorine pesticides. There has been shown that aldrin could be transformed to its metabolites, such as dieldrin or photo-dieldrin, by microorganisms under aerobic conditions, however, limited information has been shown under anaerobic conditions. For this reason, the degradation potential of aldrin by anaerobic microorganisms obtained from indigenous river sediment was evaluated, and the effect of environmental factors such as temperatures and nutrients on the aldrin degradation was also investigated in this study.

  4. Research on the changes of some physiological parameters in several fish species under the action of the talstar insecticide

    Directory of Open Access Journals (Sweden)

    Maria Cristina PONEPAL

    2010-05-01

    Full Text Available Talstar insecticide is labeled for numerous bugs and many other household pests and lawn pests. Bifenthrin is highly toxic to fish and aquatic arthropods. Bifenhrin LC50 values range from 0.0038 to17.8 μg/L and is only slightly toxic to both waterfowl and upland game birds (LD50 values range from 1.800 mg/kg to > 2.150 mg/kg. Bifenthrin had no effect on mollusks at its limit of water solubility. This study was carried out to analyze the effects of sublethal and lethal concentrations – from 0.000625 to 0.005 ml Talstar/l water on some physiological parameters (oxygen consumption, breathing frequency, number of erythrocytes on fish belonging to three species: prussian carp (Carassius auratus gibelio Bloch, bleak (Alburnus alburnus L. and perch (Perca fluviatilis L.. The acute and subacute toxicity of Talstar insecticide was evaluated in glass aquaria under semystatic conditions. The Tlastar product, under the concentrations from 0.000625 to 0.005 ml/l water, produces, after one week of immersion, a significant decrease of the fish oxygen consumption. The insecticide has changed the fish respiratory rhythm in all investigated concentrations after seven days of exposure. The number of erythrocytes has significantly decrease after seven days of immersion at insecticide concentrations of 0.000625 ml Talstar/l water (bleak and perch and 0.00125 (prussian carp ml Talstar/l water. From the three investigated fish species, the perch proved to be the most sensitive to the action of the toxic substance, followed by the bleak and the prussian carp.

  5. Analysis of structure -activity relationship and toxicity of organophosphorus pesticide to plankton%有机磷农药的构效关系及其对浮游生物的毒性效应

    Institute of Scientific and Technical Information of China (English)

    王娜; 刘莉莉; 孙凯峰; 段舜山

    2012-01-01

    The toxicity of six organophosphorus pesticides to Scenedesmus quadricanda and Moina macrocopa were studied using quantitative structure-activity relationship theory (QSAR) and acute toxicity tests. According to QSAR theory, the toxicity of organophosphorus pesticides was determined mainly by the electropositivity of center phosphorus atom, which was influenced by the type. More specifically, toxicity was reduced as P=O bonds were replaced by P=S bonds. Replacement of hydroxy(-OH) by methoxy(-CH3O), ethoxy(-CH3CH2O) and propoxy(-CH3CH2CH2O), however, successively increased. Toxicity of organophosphorus pesticides was also reduced as P-0 bond were replaced by P-C bond. Specifically, the toxicity of chlorpyrifos and phoxim was higher than four other organophosphorus pesticides as -CH3CH2O replaced -CH3O, dichlorovos and trichlorphon were more toxic than glyphosate compared, while dichlorovos was more toxic than trichlorphon. Glyphosate-isophopylammianium was the least toxic compound as hydroxy(-OH) replaced by glycine isophopylammianium. Toxicity tests demonstrated that the EC-50 concentrations of chlorpyrifos, phoxim, trichlorphon, dichlorovos, dimethoate, glyphosate-isophopylammianium on S. Quadricanda were 6.34, 6.62, 59.53, 82.12, 141.37 and 7.25 mg·L-1 at 96 h, respectively, while, those on M. Macrocopa were 0.20, 0.12, 0.28, 0.17, 1.12 and 5.03 mg·L-1 at 48 h, respectively. The toxicity of the six organophosphorus pesticide to M. Macrocopa was generally ordered as -OH>=O >-O. In conclusion, this study demonstrates the utility of using QSAR with acute toxicity test for the assessment of ecological risks of organophosphorus pesticides to plankton.%以定量构效关系理论和实验室内急性毒性试验相结合研究了六种有机磷农药对四尾栅藻(S.quadricanda)和多刺裸腹溞(Moina macrocopa)的生态毒性.有机磷农药的毒性取决于磷原子的电正性,各取代基种类和构象对电荷分布作用显著.根据构效关系原理,磷

  6. Azobenzene Modified Imidacloprid Derivatives as Photoswitchable Insecticides: Steering Molecular Activity in a Controllable Manner

    Science.gov (United States)

    Xu, Zhiping; Shi, Lina; Jiang, Danping; Cheng, Jiagao; Shao, Xusheng; Li, Zhong

    2015-10-01

    Incorporating the photoisomerizable azobenzene into imidacloprid produced a photoswitchable insecticidal molecule as the first neonicotinoid example of remote control insecticide performance with spatiotemporal resolution. The designed photoswitchable insecticides showed distinguishable activity against Musca both in vivo and in vitro upon irradiation. Molecular docking study further suggested the binding difference of the two photoisomers. The generation of these photomediated insecticides provides novel insight into the insecticidal activity facilitating further investigation on the functions of insect nicotinic acetylcholine receptors and opens a novel way to control and study insect behavior on insecticide poisoning using light.

  7. Plant compounds insecticide activity against Coleoptera pests of stored products

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Marcio Dionizio; Picanco, Marcelo Coutinho; Guedes, Raul Narciso Carvalho; Campos, Mateus Ribeiro de; Silva, Gerson Adriano; Martins, Julio Claudio [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Animal]. E-mail: marcio.dionizio@gmail.com; picanco@ufv.br; guedes@ufv.br; mateusc3@yahoo.com.br; agronomiasilva@yahoo.com.br

    2007-07-15

    The objective of this work was to screen plants with insecticide activity, in order to isolate, identify and assess the bioactivity of insecticide compounds present in these plants, against Coleoptera pests of stored products: Oryzaephilus surinamensis L. (Silvanidae), Rhyzopertha dominica F. (Bostrichidae) and Sitophilus zeamais Mots. (Curculionidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetifolia (L.) R.Br.), jimson weed (Datura stramonium L.), baleeira herb (Cordia verbenacea L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.), and billy goat weed or mentrasto (Ageratum conyzoides L.). The insecticide activity of hexane and ethanol extracts from those plants on R. dominica was evaluated. Among them, only hexane extract of A. conyzoides showed insecticide activity; the hexane extract of this species was successively fractionated by silica gel column chromatography, for isolation and purification of the active compounds. Compounds 5,6,7,8,3',4',5'-heptamethoxyflavone; 5,6,7,8,3'-pentamethoxy-4',5'-methilenedioxyflavone and coumarin were identified. However, only coumarin showed insecticide activity against three insect pests (LD{sub 50} from 2.72 to 39.71 mg g{sup -1} a.i.). The increasing order of insects susceptibility to coumarin was R. dominica, S. zeamais and O. surinamensis. (author)

  8. The global status of insect resistance to neonicotinoid insecticides.

    Science.gov (United States)

    Bass, Chris; Denholm, Ian; Williamson, Martin S; Nauen, Ralf

    2015-06-01

    The first neonicotinoid insecticide, imidacloprid, was launched in 1991. Today this class of insecticides comprises at least seven major compounds with a market share of more than 25% of total global insecticide sales. Neonicotinoid insecticides are highly selective agonists of insect nicotinic acetylcholine receptors and provide farmers with invaluable, highly effective tools against some of the world's most destructive crop pests. These include sucking pests such as aphids, whiteflies, and planthoppers, and also some coleopteran, dipteran and lepidopteran species. Although many insect species are still successfully controlled by neonicotinoids, their popularity has imposed a mounting selection pressure for resistance, and in several species resistance has now reached levels that compromise the efficacy of these insecticides. Research to understand the molecular basis of neonicotinoid resistance has revealed both target-site and metabolic mechanisms conferring resistance. For target-site resistance, field-evolved mutations have only been characterized in two aphid species. Metabolic resistance appears much more common, with the enhanced expression of one or more cytochrome P450s frequently reported in resistant strains. Despite the current scale of resistance, neonicotinoids remain a major component of many pest control programmes, and resistance management strategies, based on mode of action rotation, are of crucial importance in preventing resistance becoming more widespread. In this review we summarize the current status of neonicotinoid resistance, the biochemical and molecular mechanisms involved, and the implications for resistance management.

  9. Insecticidal and Nematicidal Activities of Novel Mimosine Derivatives.

    Science.gov (United States)

    Nguyen, Binh Cao Quan; Chompoo, Jamnian; Tawata, Shinkichi

    2015-09-14

    Mimosine, a non-protein amino acid, is found in several tropical and subtropical plants, which has high value for medicine and agricultural chemicals. Here, in continuation of works aimed to development of natural product-based pesticidal agents, we present the first significant findings for insecticidal and nematicidal activities of novel mimosine derivatives. Interestingly, mimosinol and deuterated mimosinol (D-mimosinol) from mimosine had strong insecticidal activity which could be a result of tyrosinase inhibition (IC50 = 31.4 and 46.1 μM, respectively). Of synthesized phosphoramidothionate derivatives from two these amino alcohols, two compounds (1a and 1b) showed high insecticidal activity (LD50 = 0.5 and 0.7 μg/insect, respectively) with 50%-60% mortality at 50 μg/mL which may be attributed to acetylcholinesterase inhibition. Compounds 1a and 1b also had strong nematicidal activity with IC50 = 31.8 and 50.2 μM, respectively. Our results suggest that the length of the alkyl chain and the functional group at the C₅-position of phosphoramidothionates derived from mimosinol and d-mimosinol are essential for the insecticidal and nematicidal activities. These results reveal an unexplored scaffold as new insecticide and nematicide.

  10. RESISTANCE OF THE TOXAPHENE INSECTICIDE IN SOIL

    Directory of Open Access Journals (Sweden)

    G MIRSATTARI

    2001-06-01

    Full Text Available Introduction. Toxaphene is resistant to degration and has been known as persistent bioaccumulator. In oder to understand the persistence and degradation phenomena of toxaphene in soil a series of tests were run. Methods. All experiments for dry and moist soil were conducted with 10 to 20 kg soil samples, contained in plastic tubs. The experiment was carried out in two parts. The five samples studied in each part are described below. Part I: "Dry samples". Soil control I soil amended with 10 percent gin trash/soil amended with 25 percent gin trash/soil amended with 10 percent gin trash and treated with 500 ppm toxaphene and soil treated with 500 ppm toxaphene. These samples were kept dry during the entire experimental period. Part II: "Moist samples". The samples were the same as described in part I, but they were kept moist by addition of water weekly during the experimental period. Periodically twenty grams of soil were analyzed using a gas chromatograph. Results. Chromatograms of dry and moist samples from soil containers (Part I and II analyzed up to 12 months after initiation of the experiments showed that no toxaphene degradation or dissipation had occurred. GLC profiles of extracts of 12 months soil samples were identical to those of 0 dry samples and almost 100 percent of toxaphene was recovered in all samples after one year regardless of whether samples were dry or moist I amended or not. Discussion. The results suggest that toxaphene dose not undergo degradation in soil" under aerobic condition, so it can be a persistent insecticide in soil under environmental condition.

  11. Resistance to bio-insecticides or how to enhance their sustainability: a review.

    Science.gov (United States)

    Siegwart, Myriam; Graillot, Benoit; Blachere Lopez, Christine; Besse, Samantha; Bardin, Marc; Nicot, Philippe C; Lopez-Ferber, Miguel

    2015-01-01

    After more than 70 years of chemical pesticide use, modern agriculture is increasingly using biological control products. Resistances to conventional insecticides are wide spread, while those to bio-insecticides have raised less attention, and resistance management is frequently neglected. However, a good knowledge of the limitations of a new technique often provides greater sustainability. In this review, we compile cases of resistance to widely used bio-insecticides and describe the associated resistance mechanisms. This overview shows that all widely used bio-insecticides ultimately select resistant individuals. For example, at least 27 species of insects have been described as resistant to Bacillus thuringiensis toxins. The resistance mechanisms are at least as diverse as those that are involved in resistance to chemical insecticides, some of them being common to bio-insecticides and chemical insecticides. This analysis highlights the specific properties of bio-insecticides that the scientific community should use to provide a better sustainability of these products.

  12. Influence of Pyrethroid Insecticides on Sodium and Calcium Influx in Neocortical Neurons

    Science.gov (United States)

    Pyrethroid insecticides bind to voltage-gated sodium channels and modify their gating kinetics, thereby disrupting neuronal function. Using murine neocortical neurons in primary culture, we have compared the ability of 11 structurally diverse pyrethroid insecticides to evoke Na+ ...

  13. Efficacy of an insecticide paint against insecticide-susceptible and resistant mosquitoes - Part 1: Laboratory evaluation

    Directory of Open Access Journals (Sweden)

    Carnevale Pierre

    2010-11-01

    Full Text Available Abstract Background The main malaria vector Anopheles gambiae and the urban pest nuisance Culex quinquefasciatus are increasingly resistant to pyrethroids in many African countries. There is a need for new products and strategies. Insecticide paint Inesfly 5A IGR™, containing two organophosphates (OPs, chlorpyrifos and diazinon, and insect growth regulator (IGR, pyriproxyfen, was tested under laboratory conditions for 12 months following WHOPES Phase I procedures. Methods Mosquitoes used were laboratory strains of Cx. quinquefasciatus susceptible and resistant to OPs. The paint was applied at two different doses (1 kg/6 m2 and 1 kg/12 m2 on different commonly used surfaces: porous (cement and stucco and non-porous (softwood and hard plastic. Insecticide efficacy was studied in terms of delayed mortality using 30-minute WHO bioassay cones. IGR efficacy on fecundity, fertility and larval development was studied on OP-resistant females exposed for 30 minutes to cement treated and control surfaces. Results After treatment, delayed mortality was high (87-100% even against OP-resistant females on all surfaces except cement treated at 1 kg/12 m2. Remarkably, one year after treatment delayed mortality was 93-100% against OP-resistant females on non-porous surfaces at both doses. On cement, death rates were low 12 months after treatment regardless of the dose and the resistance status. Fecundity, fertility and adult emergence were reduced after treatment even at the lower dose (p -3. A reduction in fecundity was still observed nine months after treatment at both doses (p -3 and adult emergence was reduced at the higher dose (p -3. Conclusions High mortality rates were observed against laboratory strains of the pest mosquito Cx. quinquefasciatus susceptible and resistant to insecticides. Long-term killing remained equally important on non-porous surfaces regardless the resistance status for over 12 months. The paint's effect on fecundity, fertility and

  14. Modeling the integration of parasitoid, insecticide, and transgenic insecticidal crop for the long-term control of an insect pest.

    Science.gov (United States)

    Onstad, David W; Liu, Xiaoxia; Chen, Mao; Roush, Rick; Shelton, Anthony M

    2013-06-01

    The tools of insect pest management include host plant resistance, biological control, and insecticides and how they are integrated will influence the durability of each. We created a detailed model of the population dynamics and population genetics of the diamondback moth, Plutella xylostella L., and its parasitoid, Diadegma insulare (Cresson), to study long-term pest management in broccoli Brassica oleracea L. Given this pest's history of evolving resistance to various toxins, we also evaluated the evolution of resistance to transgenic insecticidal Bt broccoli (expressing Cry1Ac) and two types of insecticides. Simulations demonstrated that parasitism provided the most reliable, long-term control of P. xylostella populations. Use of Bt broccoli with a 10% insecticide-free refuge did not reduce the long-term contribution of parasitism to pest control. Small refuges within Bt broccoli fields can delay evolution of resistance > 30 generations if resistance alleles are rare in the pest population. However, the effectiveness of these refuges can be compromised by insecticide use. Rainfall mortality during the pest's egg and neonate stages significantly influences pest control but especially resistance management. Our model results support the idea that Bt crops and biological control can be integrated in integrated pest management and actually synergistically support each other. However, the planting and maintenance of toxin-free refuges are critical to this integration.

  15. Toxicity, synergism, and neurological effects of novel volatile insecticides in insecticide-susceptible and -resistant Drosophila strains.

    Science.gov (United States)

    Nguyen, Sam N; Song, Cheol; Scharf, Michael E

    2007-04-01

    Naturally derived volatile insecticides from the heterobicyclic and formate ester classes were investigated using a combination of volatility and synergist bioassays. In these studies, Drosophila melanogaster (Meigen) was used as a model for other medically important dipterans. In addition to a susceptible strain (Canton-S), three mutant strains were tested that included a strain resistant by P450-based metabolism (Hikone-R) and two resistant neurological mutant strains; one voltage-gated sodium channel mutant (para(ts-1)) and one GABA-gated chloride channel mutant (Rdl). In general, the 11 tested insecticides displayed a diversity of toxicity, metabolism, and resistance characteristics that correlate with their structural diversity. Several important trends were revealed by these studies, including hydrolase- and cytochrome P450 (P450)-based activation, P450-based resistance, distinct patterns of neurological activity, and negative cross-resistance with established insecticides. These findings provide important insight into the metabolism and modes of action for the volatile insecticides. These findings also suggest potential approaches for insecticide deployment in integrated vector management and resistance management programs.

  16. Insecticide Resistance in the Western Flower Thrips, Frankliniella occidentalis

    DEFF Research Database (Denmark)

    Jensen, Sten Erik

    The western flower thrips, Frankliniella occidentalis (Pergande) is a serious pest on a wide range of crops throughout the world. In Denmark F. occidentalis is a pest in greenhouses. F. occidentalis is difficult to control with insecticides because of its thigmokinetic behaviour and resistance...... to insecticides. Since F. occidentulis spread to become a worldwide pest in 1980’es, resistance to a number of different insecticides has been shown in many populations of F. occidentalis. This flower thrips has the potential of fast development of resistance owing to the short generation time, high fecundity......, and a haplodiploid breeding system. Although resistance in F. occidentalis is a common problem, the underlying mechanisms conferring resistance have only been studied on a few populations. A purpose of this study was to gain more knowledge about possible resistance mechanisms in F. occidentulis and, furthermore...

  17. Acute pancreatitis

    Directory of Open Access Journals (Sweden)

    Bo-Guang Fan

    2010-01-01

    Full Text Available Background : Acute pancreatitis continues to be a serious illness, and the patients with acute pancreatitis are at risk to develop different complications from ongoing pancreatic inflammation. Aims : The present review is to highlight the classification, treatment and prognosis of acute pancreatitis. Material & Methods : We reviewed the English-language literature (Medline addressing pancreatitis. Results : Acute pancreatitis is frequently caused by gallstone disease or excess alcohol ingestion. There are a number of important issues regarding clinical highlights in the classification, treatment and prognosis of acute pancreatitis, and treatment options for complications of acute pancreatitis including pancreatic pseudocysts. Conclusions : Multidisciplinary approach should be used for the management of the patient with acute pancreatitis.

  18. Acute pancreatitis

    Directory of Open Access Journals (Sweden)

    Bo-Guang Fan

    2010-05-01

    Full Text Available Background: Acute pancreatitis continues to be a serious illness, and the patients with acute pancreatitis are at risk to develop different complications from ongoing pancreatic inflammation. Aims: The present review is to highlight the classification, treatment and prognosis of acute pancreatitis. Material & Methods: We reviewed the English-language literature (Medline addressing pancreatitis. Results: Acute pancreatitis is frequently caused by gallstone disease or excess alcohol ingestion. There are a number of important issues regarding clinical highlights in the classification, treatment and prognosis of acute pancreatitis, and treatment options for complications of acute pancreatitis including pancreatic pseudocysts. Conclusions: Multidisciplinary approach should be used for the management of the patient with acute pancreatitis.

  19. Insecticide resistance status in Anopheles gambiae in southern Benin

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    Corbel Vincent

    2010-03-01

    Full Text Available Abstract Background The emergence of pyrethroid resistance in Anopheles gambiae has become a serious concern to the future success of malaria control. In Benin, the National Malaria Control Programme has recently planned to scaling up long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS for malaria prevention. It is, therefore, crucial to monitor the level and type of insecticide resistance in An. gambiae, particularly in southern Benin where reduced efficacy of insecticide-treated nets (ITNs and IRS has previously been reported. Methods The protocol was based on mosquito collection during both dry and rainy seasons across forty districts selected in southern Benin. Bioassay were performed on adults collected from the field to assess the susceptibility of malaria vectors to insecticide-impregnated papers (permethrin 0.75%, delthamethrin 0.05%, DDT 4%, and bendiocarb 0.1% following WHOPES guidelines. The species within An. gambiae complex, molecular form and presence of kdr and ace-1 mutations were determined by PCR. Results Strong resistance to permethrin and DDT was found in An. gambiae populations from southern Benin, except in Aglangandan where mosquitoes were fully susceptible (mortality 100% to all insecticides tested. PCR showed the presence of two sub-species of An. gambiae, namely An. gambiae s.s, and Anopheles melas, with a predominance for An. gambiae s.s (98%. The molecular M form of An. gambiae was predominant in southern Benin (97%. The kdr mutation was detected in all districts at various frequency (1% to 95% whereas the Ace-1 mutation was found at a very low frequency (≤ 5%. Conclusion This study showed a widespread resistance to permethrin in An. gambiae populations from southern Benin, with a significant increase of kdr frequency compared to what was observed previously in Benin. The low frequency of Ace-1 recorded in all populations is encouraging for the use of bendiocarb as an alternative insecticide to

  20. Insecticide resistance in vector Chagas disease: evolution, mechanisms and management.

    Science.gov (United States)

    Mougabure-Cueto, Gastón; Picollo, María Inés

    2015-09-01

    Chagas disease is a chronic parasitic infection restricted to America. The disease is caused by the protozoa Trypanosoma cruzi, which is transmitted to human through the feces of infected triatomine insects. Because no treatment is available for the chronic forms of the disease, vector chemical control represents the best way to reduce the incidence of the disease. Chemical control has been based principally on spraying dwellings with insecticide formulations and led to the reduction of triatomine distribution and consequent interruption of disease transmission in several areas from endemic region. However, in the last decade it has been repeatedly reported the presence triatomnes, mainly Triatoma infestans, after spraying with pyrethroid insecticides, which was associated to evolution to insecticide resistance. In this paper the evolution of insecticide resistance in triatomines is reviewed. The insecticide resistance was detected in 1970s in Rhodnius prolixus and 1990s in R. prolixus and T. infestans, but not until the 2000s resistance to pyrthroids in T. infestans associated to control failures was described in Argentina and Bolivia. The main resistance mechanisms (i.e. enhanced metabolism, altered site of action and reduced penetration) were described in the T. infestans resistant to pyrethrods. Different resistant profiles were demonstrated suggesting independent origin of the different resistant foci of Argentina and Bolivia. The deltamethrin resistance in T. infestans was showed to be controlled by semi-dominant, autosomally inherited factors. Reproductive and developmental costs were also demonstrated for the resistant T. infestans. A discussion about resistance and tolerance concepts and the persistence of T. infestans in Gran Chaco region are presented. In addition, theoretical concepts related to toxicological, evolutionary and ecological aspects of insecticide resistance are discussed in order to understand the particular scenario of pyrethroid

  1. Optimal Cotton Insecticide Application Termination Timing: A Meta-Analysis.

    Science.gov (United States)

    Griffin, T W; Zapata, S D

    2016-08-01

    The concept of insecticide termination timing is generally accepted among cotton (Gossypium hirsutum) researchers; however, exact timings are often disputed. Specifically, there is uncertainty regarding the last economic insecticide application to control fruit-feeding pests including tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)), boll weevil (Anthonomus grandis), bollworm (Helicoverpa zea), tobacco budworm (Heliothis virescens), and cotton fleahopper (Pseudatomoscelis seriatus). A systematic review of prior studies was conducted within a meta-analytic framework. Nine publicly available articles were amalgamated to develop an optimal timing principle. These prior studies reported 53 independent multiple means comparison field experiments for a total of 247 trial observations. Stochastic plateau theory integrated with econometric meta-analysis methodology was applied to the meta-database to determine the shape of the functional form of both the agronomic optimal insecticide termination timing and corresponding yield potential. Results indicated that current university insecticide termination timing recommendations are later than overall estimated timing suggested. The estimated 159 heat units (HU) after the fifth position above white flower (NAWF5) was found to be statistically different than the 194 HU termination used as the status quo recommended termination timing. Insecticides applied after 159 HU may have been applied in excess, resulting in unnecessary economic and environmental costs. Empirical results also suggested that extending the insecticide termination time by one unit resulted in a cotton lint yield increase of 0.27 kilograms per hectare up to the timing where the plateau began. Based on economic analyses, profit-maximizing producers may cease application as soon as 124 HU after NAWF5. These results provided insights useful to improve production systems by applying inputs only when benefits were expected to be in excess of the

  2. Novel AChE inhibitors for sustainable insecticide resistance management.

    Directory of Open Access Journals (Sweden)

    Haoues Alout

    Full Text Available Resistance to insecticides has become a critical issue in pest management and it is particularly chronic in the control of human disease vectors. The gravity of this situation is being exacerbated since there has not been a new insecticide class produced for over twenty years. Reasoned strategies have been developed to limit resistance spread but have proven difficult to implement in the field. Here we propose a new conceptual strategy based on inhibitors that preferentially target mosquitoes already resistant to a currently used insecticide. Application of such inhibitors in rotation with the insecticide against which resistance has been selected initially is expected to restore vector control efficacy and reduce the odds of neo-resistance. We validated this strategy by screening for inhibitors of the G119S mutated acetylcholinesterase-1 (AChE1, which mediates insensitivity to the widely used organophosphates (OP and carbamates (CX insecticides. PyrimidineTrione Furan-substituted (PTF compounds came out as best hits, acting biochemically as reversible and competitive inhibitors of mosquito AChE1 and preferentially inhibiting the mutated form, insensitive to OP and CX. PTF application in bioassays preferentially killed OP-resistant Culex pipiens and Anopheles gambiae larvae as a consequence of AChE1 inhibition. Modeling the evolution of frequencies of wild type and OP-insensitive AChE1 alleles in PTF-treated populations using the selectivity parameters estimated from bioassays predicts a rapid rise in the wild type allele frequency. This study identifies the first compound class that preferentially targets OP-resistant mosquitoes, thus restoring OP-susceptibility, which validates a new prospect of sustainable insecticide resistance management.

  3. REVIEW ON THE EFFICACY OF INSECTICIDES AND BIO-INSECTICIDES (PATHOGEN AND IGR AGAINST VECTOR DISEASES EVALUATIONS CONDUCTED BY VRCRU (2001-2002

    Directory of Open Access Journals (Sweden)

    Damar Tri Boewono

    2012-11-01

    Full Text Available Vector and Reservoir Control Research Unit (VRCRU Salatiga, as WHO Collaborating Center for Pesticide Evaluation, has evaluate the efficacy of several new insecticides for various purposes especially for the registration in Indonesia Pesticide Commission. This unit has evaluated insecticides inc ollaboration with pesticide companies and WHO. The aim of the studies were to provide the efficacy and residual effect of insecticides against vector disease. Such as malaria, dengue haemorrhagic fever (DHF, filariasis, plague, diarrhea, etc. The studied insecticides in the unit were belong to Organophosphate, Carbamate and Synthetic Phyrethroid compounds and also bio-insecticides (pathogen & Insect Grow Regulator/IGR. Various insecticide applications were performed against the adult, e.g. residual spraying (IRS, thermal fogging, Ultra Low Volume (ULV, bed nets impregnation. The study was also conducted to evaluate the efficacy of insecticides, bio-insecticides (pathogen and IGR against mosquito larvae as well as insecticides against fleas and cockroaches. This paper is an overall review of the related studies which were conducted on 2001-2002. Keywords: efficacy, bio-insecticides, vector disease

  4. AGE-DEPENDENT HEAPATIC AND PLASMA METABOLISM OF DELTAMETHRIN IN VITRO: ROLE IN ACUTE NEUROTOXICITY.

    Science.gov (United States)

    Deltamethrin (DLM) is a relatively potent and a widely used pyrethroid insecticide. Inefficient metabolism is proposed to be the reason for the greater sensitivity of immature rats to DLM acute neurotoxicity. The aim of this study was to test this hypothesis by characterizing the...

  5. New Insecticides and Repellents For Use on Mosquitoes and Sand Flies

    Science.gov (United States)

    The major emphasis of our research is on the discovery and development of new insecticides for personal protection. The insecticide discovery effort involves structure-activity modeling to correlate molecular structure and electronic properties with repellent and/or insecticidal activity. Models a...

  6. Toxaphene, a complex mixture of polychloroterpenes and a major insecticide, is mutagenic

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, N.K.; Ames, B.N.; Saleh, M.A.; Casida, J.E.

    1979-08-10

    Toxaphene, the most widely used chlorinated insecticide, is mutagenic in the Salmonella test without requiring liver homogenate for activity. This insecticide is a complex mixture (more than 177 polychloroterpenes) with carcinogenic activity in rodents. Some but not all of the mutagenic components are easily separated from the insecticidal ingredients.

  7. Biosensors and their applications in detection of organophosphorus pesticides in the environment.

    Science.gov (United States)

    Hassani, Shokoufeh; Momtaz, Saeideh; Vakhshiteh, Faezeh; Maghsoudi, Armin Salek; Ganjali, Mohammad Reza; Norouzi, Parviz; Abdollahi, Mohammad

    2017-01-01

    This review discusses the past and recent advancements of biosensors focusing on detection of organophosphorus pesticides (OPs) due to their exceptional use during the last decades. Apart from agricultural benefits, OPs also impose adverse toxicological effects on animal and human population. Conventional approaches such as chromatographic techniques used for pesticide detection are associated with several limitations. A biosensor technology is unique due to the detection sensitivity, selectivity, remarkable performance capabilities, simplicity and on-site operation, fabrication and incorporation with nanomaterials. This study also provided specifications of the most OPs biosensors reported until today based on their transducer system. In addition, we highlighted the application of advanced complementary materials and analysis techniques in OPs detection systems. The availability of these new materials associated with new sensing techniques has led to introduction of easy-to-use analytical tools of high sensitivity and specificity in the design and construction of OPs biosensors. In this review, we elaborated the achievements in sensing systems concerning innovative nanomaterials and analytical techniques with emphasis on OPs.

  8. Adsorption of organophosphorus pesticides in tropical soils: The case of karst landscape of northwestern Yucatan.

    Science.gov (United States)

    Alfonso, Lorenzo-Flores; Germán, Giácoman Vallejos; María Del Carmen, Ponce Caballero; Hossein, Ghoveisi

    2017-01-01

    This article discusses the adsorption of four organophosphorus pesticides-diazinon, dimethoate, methyl parathion, and sulfotep-in soil samples from four sites-Komchén, Xcanatún, Chablekal and Mocochá- in the northwest of Yucatan, Mexico. These pesticides have been detected in groundwater at concentrations greater than 5 (μg/L) during recent monitoring campaigns in the study area. In this region, groundwater contamination is exacerbated by its karst aquifer, which is susceptible to contamination and is considered very vulnerable. The experimental work was carried out using the batch equilibrium technique. Pesticide analyses by solid-phase extraction and gas chromatography were performed. The equilibrium adsorption data were analyzed by Henry, Langmuir and Freundlich models. The results indicate that the Freundlich model provides the best correlation of the experimental data. Freundlich adsorption coefficients Kf were in the range of 1.62-2.35 for sulfotep, 2.43 to 3.25 for dimethoate, from 5.54 to 9.27 for methyl parathion, and 3.22 to 5.17 for diazinon. Freundlich adsorption coefficients were normalized to the content of organic carbon in the soil to estimate the sorption coefficient of organic carbon (KOC). KOC values were in the range of 9.45-71.80, indicated that four pesticides have low adsorption on the four studied soils, which represents a high risk of contamination to the aquifer.

  9. Biosensor based on Prussian blue nanocubes/reduced graphene oxide nanocomposite for detection of organophosphorus pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lin; Zhang, Aidong; Du, Dan; Lin, Yuehe

    2012-07-13

    We demonstrate a facile procedure to efficiently prepare Prussian blue nanocubes/reduced graphene oxide (PBNCs/rGO) nanocomposite by directly mixing Fe3+ and [Fe(CN)6]3 in the presence of GO in polyethyleneimine aqueous solution, resulting in a novel acetylcholinesterase (AChE) biosensor for detection of organophosphorus pesticides (OPs). The obtained nanocomposite was characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) microanalysis. It was clearly observed that the nanosheet has been decorated with cubic PB nanoparticles and nearly all the nanoparticles are distributed uniformly only on the surface of the reduced GO. No isolated PB nanoparticles were observed, indicating the strong interaction between PB nanocubes and the reduced GO and the formation of PBNCs/rGO nanocomposite. The obtained PBNCs/rGO based AChE biosensor make the peak potential shift negatively to 220 mV. The AChE biosensor shows rapid response and high sensitivity for detection of monocrotophos. These results suggest that the PBNCs/rGO hybrids nanocomposite exhibited high electrocatalytic activity towards the oxidation of thiocholine, which lead to the sensitive detection of OP pesticides.

  10. Gestational Hypertension and Organophosphorus Pesticide Exposure: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Caterina Ledda

    2015-01-01

    Full Text Available Hypertension is the most common medical problem encountered during pregnancy, complicating 2-3% of pregnancies. High blood pressure (BP with diastolic BP ≥ 90 mm Hg and/or systolic BP ≥ 140 mm Hg arising after week 22 of pregnancy and resolving after delivery is defined as gestational hypertension (GHY. The aim of this cross-sectional study was to investigate whether occupational and/or environmental exposure to organophosphorus (OP pesticide affects GHY. Women at approximately 22 weeks of gestation were recruited. OP pesticide exposure in the first trimester of pregnancy was classified into four categories: no exposure, indirect exposure, domestic exposure, and occupational exposure. Application of the exclusion criteria left 2203 participants (mean age 30.4 ± 11.6 years. Data analysis showed that in women with indirect OP pesticide exposure the incidence of GHY was slightly higher than that in the world population, whereas domestic exposure involved a 7% increase and occupational exposure a 12% increase. Analysis of the pesticides used by participants highlighted a possible role for malathion and diazinon (adjusted OR 1.09 and 1.14, resp.. Further investigation of exposed workers and the general population is clearly warranted given the broad diffusion of OP pesticides and their possible public health impact, maybe by including a wider range of health outcomes.

  11. Suicidal Death due to Organophosphorus Compound Poisoning ─ an Experience of 67 Cases

    Directory of Open Access Journals (Sweden)

    Nashid Tabassum Khan

    2016-05-01

    Full Text Available Background: Bangladesh is an agro-based country. Suicide by agrochemical compounds are increasing day by day in this country. Organophosphorus compounds (OPC are commonly used for suicide. Mostly these are used for suicidal purpose in rural areas in our country due to low cost, toxicity and availability. Objective: To find out the relationship of age and sex variation along with the causes that influenced different income group people to ingest OPC for committing suicide. Materials and Methods: This study was conducted in the Department of Forensic Medicine, Dhaka Medical College during January to December 2010. Data were collected at the time of autopsy and from postmortem examination report of viscera. Viscera were preserved and sent to the Chief Chemical Examiner’s Office, Dhaka for toxicological analysis. Results: In this study, middle aged subjects (20–30 years were found to commit suicide using OPC in comparison to other age groups. Among the cases male were 57% and female 43%. Poverty was found as the most common cause (20% of OPC poisoning. Conclusion: Poverty is the leading cause of death of OPC poisoning followed by failure in love and adultery. Business failure, unhappiness in conjugal life, demand for dowry and violence against women are other causes to commit suicide by OPC.

  12. [Contamination of Organophosphorus Pesticides Residue in Fresh Vegetables and Related Health Risk Assessment in Changchun, China].

    Science.gov (United States)

    Yu, Rui; Liu, Jing-shuang; Wang, Qi-cun; Liu, Qiang; Wang, Yang

    2015-09-01

    This study aims to investigate the concentrations of organophosphorus pesticides (OPs) in fresh vegetables. A total of Z14 samples from seven types of vegetables were collected from the suburb in Changchun City. The OPs were analyzed by gas chromatography coupled with flame photometric detector (GC-FPD). Target hazard quotients (THQ) were applied to estimate the potential health risk to inhabitants. Results showed that OPs concentrations exceeded the Maximum Residue Limit (MRL) in more than 23. 4% samples, and were not detected in only 7. 9% samples. Detection rates of OPs was as follow in the decreased order: diazinon (82. 2%) > phorate (45. 8%) > dimethoate (29. 4%) > parathion-methyl (27. 6%) > omethoate (23. 8%) > dichlorvos (22. 9%) > fenitrothion (21%) > fenthion (18. 7%) > parathion (18. 2%) > methamidophos (17. 3%) > malathion (12. 1%). The percentages above MRL for leaves were higher than for non-leafy vegetables. The order of percentages of OPs above MRL was as follows: green onion (82. 5%) > radish (37. 5%) > red pepper (17. 2%) > Chinese vegetable (14. 3%) > cucumber (3. 2%) > eggplant (2. 9%) > tomato (0%). 49. 5% vegetables samples showed more than one OP. The average target hazard quotients (ave THQ) were all less than one and the average Hazard Index (ave HI) was 0. 462, so that inhabitants who expose average OP levels may not experience adverse health effects.

  13. Computational Enzymology and Organophosphorus Degrading Enzymes: Promising Approaches Toward Remediation Technologies of Warfare Agents and Pesticides.

    Science.gov (United States)

    Ramalho, Teodorico C; de Castro, Alexandre A; Silva, Daniela R; Silva, Maria Cristina; Franca, Tanos C C; Bennion, Brian J; Kuca, Kamil

    2016-01-01

    The re-emergence of chemical weapons as a global threat in hands of terrorist groups, together with an increasing number of pesticides intoxications and environmental contaminations worldwide, has called the attention of the scientific community for the need of improvement in the technologies for detoxification of organophosphorus (OP) compounds. A compelling strategy is the use of bioremediation by enzymes that are able to hydrolyze these molecules to harmless chemical species. Several enzymes have been studied and engineered for this purpose. However, their mechanisms of action are not well understood. Theoretical investigations may help elucidate important aspects of these mechanisms and help in the development of more efficient bio-remediators. In this review, we point out the major contributions of computational methodologies applied to enzyme based detoxification of OPs. Furthermore, we highlight the use of PTE, PON, DFP, and BuChE as enzymes used in OP detoxification process and how computational tools such as molecular docking, molecular dynamics simulations and combined quantum mechanical/molecular mechanics have and will continue to contribute to this very important area of research.

  14. Separation and concentration of lanthanoids using microcapsules containing acidic organophosphorus compounds as an extractant

    Energy Technology Data Exchange (ETDEWEB)

    Kamio, Eiji; Kondo, Kazuo [Doshisha Univ., Department of Chemical Engineering and Materials Science, Kyoto (Japan)

    2002-06-01

    In this study, we measured the extraction equilibria of lanthanoids with microcapsules containing acidic organophosphorus compound as an extractant and discuss their mutual separation by using a column packed with the microcapsules. The extraction equilibria of lanthanoids into the microcapsules containing 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPNA) were elucidated and the extraction equilibrium constants were calculated by slope-analysis method. It was suggested that the lanthanoid ions are extracted in the microcapsules in a high loading state. Furthermore, the adsorption behavior of lanthanoids into the column packed with the microcapsules containing EHPNA was observed. It was found that adsorption and elution of lanthanoids are briefly achieved by selecting pH of the feed aqueous solution. However, it was impossible to separate them only in adsorption or elution operation. So, the mutual separation of lanthanoids was investigated using the adsorption column connected to the development column containing microcapsules. By selecting pH of the eluent, each metal was separated mutually in more than 95% of purity. The metal ions in the eluent from the development column could be concentrated by treating it with a column packed with the microcapsules containing di(2-ethylhexyl) phosphoric acid (D2EHPA). Considering these information, it will be possible to design a continuous extracting, separating and concentrating reactor of lanthanoids using a column packed with the microcapsules. (author)

  15. Partitioning of organophosphorus pesticides into phosphatidylcholine small unilamellar vesicles studied by second-derivative spectrophotometry.

    Science.gov (United States)

    Takegami, Shigehiko; Kitamura, Keisuke; Ohsugi, Mayuko; Ito, Aya; Kitade, Tatsuya

    2015-06-15

    In order to quantitatively examine the lipophilicity of the widely used organophosphorus pesticides (OPs) chlorfenvinphos (CFVP), chlorpyrifos-methyl (CPFM), diazinon (DZN), fenitrothion (FNT), fenthion (FT), isofenphos (IFP), profenofos (PFF) and pyraclofos (PCF), their partition coefficient (Kp) values between phosphatidylcholine (PC) small unilamellar vesicles (SUVs) and water (liposome-water system) were determined by second-derivative spectrophotometry. The second-derivative spectra of these OPs in the presence of PC SUV showed a bathochromic shift according to the increase in PC concentration and distinct derivative isosbestic points, demonstrating the complete elimination of the residual background signal effects that were observed in the absorption spectra. The Kp values were calculated from the second-derivative intensity change induced by addition of PC SUV and obtained with a good precision of R.S.D. below 10%. The Kp values were in the order of CPFM>FT>PFF>PCF>IFP>CFVP>FNT⩾DZN and did not show a linear correlation relationship with the reported partition coefficients obtained using an n-octanol-water system (R(2)=0.530). Also, the results quantitatively clarified the effect of chemical-group substitution in OPs on their lipophilicity. Since the partition coefficient for the liposome-water system is more effective for modeling the quantitative structure-activity relationship than that for the n-octanol-water system, the obtained results are toxicologically important for estimating the accumulation of these OPs in human cell membranes.

  16. Characterization of organophosphorus flame retardants' sorption on building materials and consumer products

    Science.gov (United States)

    Liu, Xiaoyu; Allen, Matthew R.; Roache, Nancy F.

    2016-09-01

    Better understanding the transport mechanisms of organophosphorus flame-retardants (OPFRs) in the residential environment is important to more accurately estimate their indoor exposure and develop risk management strategies that protect human health. This study describes an improved dual small chamber testing method to characterize the sorption of OPFRs on indoor building materials and consumer products. The OPFRs studied were tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP). The test materials and products used as sinks include concrete, ceiling tile, vinyl flooring, carpet, latex painted gypsum wallboard, open cell polyurethane foam, mattress pad and liner, polyester clothing, cotton clothing, and uniform shirt. During the tests, the amount of OPFRs absorbed by the materials at different exposure times was determined simultaneously. OPFRs air concentrations at the inlet and inside the test chamber were monitored. The data were used to rank the sorption strength of the OPFRs on different materials. In general, building materials exhibited relatively stronger sorption strength than clothing textiles. The material-air partition and material phase diffusion coefficients were estimated by fitting a sink model to the sorption concentration data for twelve materials with three OPFRs. They are in the range of 2.72 × 105 to 3.99 × 108 (dimensionless) for the material-air partition coefficients and 1.13 × 10-14 to 5.83 × 10-9 (m2/h) for the material phase diffusion coefficients.

  17. Hypothesis for synergistic toxicity of organophosphorus poisoning-induced cholinergic crisis and anaphylactoid reactions

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, F.M.; Shih, T.M.; Lenz, D.E.; Madsen, J.M.; Broomfield, C.A.

    1996-08-01

    The neurotoxicity of organophosphorus (OP) compounds Involves the Inhibition of acetylchollnesterase (AChE), causing accumulation of acetyicholine (ACh) at synapses. However, cholinergic crisis may not be the sole mechanism of OP toxicity. Adverse drug reactions caused by synergistic toxicity between drugs with distinct pharmacological mechanisms are a common problem. Likewise, the multiple pharmacological activities of a single molecule might also contribute to either toxicity or efficacy. For example, certain OP compounds (e.g. soman) exhibit anti-AChE activity and also act as secretagogues by inducing mast cell degranulation with associated autacoid release and anaphylactoid reactions. Anaphylactoid shock can produce a lethal syndrome with symptoms of respiratory failure and circulatory collapse similar to the physiological sequelae observed for OP poisoning. Moreover, the major classes of drugs used as antidotes for OP intoxication can affect anaphylaxis. Acetylcholine can act as an agonist of autacoid release, and autacoids such as histamine can augment soman-Induced bronchial spasm. In concert with the demonstrably critical role of cholinergic crisis In OP toxicity, the precepts of neuroimmunology indicate that secondary adverse reactions encompassing anaphylactold reactions may complicate OP toxicity.

  18. Photonic crystal sensor for organophosphate nerve agents utilizing the organophosphorus hydrolase enzyme.

    Science.gov (United States)

    Walker, Jeremy P; Kimble, Kyle W; Asher, Sanford A

    2007-12-01

    We developed an intelligent polymerized crystalline colloidal array (IPCCA) photonic crystal sensing material which reversibly senses the organophosphate compound methyl paraoxon at micromolar concentrations in aqueous solutions. A periodic array of colloidal particles is embedded in a poly-2-hydroxyethylacrylate hydrogel. The particle lattice spacing is such that the array Bragg-diffracts visible light. We utilize a bimodular sensing approach in which the enzyme organophosphorus hydrolase (OPH) catalyzes the hydrolysis of methyl paraoxon at basic pH, producing p-nitrophenolate, dimethylphosphate, and two protons. The protons lower the pH and create a steady-state pH gradient. Protonation of the phenolates attached to the hydrogel makes the free energy of mixing of the hydrogel less favorable, which causes the hydrogel to shrink. The IPCCA's lattice constant decreases, which blueshifts the diffracted light. The magnitude of the steady-state diffraction blueshift is proportional to the concentration of methyl paraoxon. The current detection limit is 0.2 micromol methyl paraoxon per liter.

  19. Nanomaterials - Acetylcholinesterase Enzyme Matrices for Organophosphorus Pesticides Electrochemical Sensors: A Review

    Directory of Open Access Journals (Sweden)

    Shen-Ming Chen

    2009-05-01

    Full Text Available Acetylcholinesterase (AChE is an important cholinesterase enzyme present in the synaptic clefts of living organisms. It maintains the levels of the neurotransmitter acetylcholine by catalyzing the hydrolysis reaction of acetylcholine to thiocholine. This catalytic activity of AChE is drastically inhibited by trace amounts of organophosphorus (OP pesticides present in the environment. As a result, effective monitoring of OP pesticides in the environment is very desirable and has been done successfully in recent years with the use of nanomaterial-based AChE sensors. In such sensors, the enzyme AChE has been immobilized onto nanomaterials like multiwalled carbon nanotubes, gold nanoparticles, zirconia nanoparticles, cadmium sulphide nano particles or quantum dots. These nanomaterial matrices promote significant enhancements of OP pesticide determinations, with the thiocholine oxidation occurring at much lower oxidation potentials. Moreover, nanomaterial-based AChE sensors with rapid response, increased operational and long storage stability are extremely well suited for OP pesticide determination over a wide concentration range. In this review, the unique advantages of using nanomaterials as AChE immobilization matrices are discussed. Further, detection limits, sensitivities and correlation coefficients obtained using various electroanalytical techniques have also been compared with chromatographic techniques.

  20. THE STUDY OF SOCIO-DEMOGRAPHIC PROFILE OF ORGANOPHOSPHORUS POISONING IN UTTAR PRADESH

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    Anurag Srivastava

    2016-07-01

    Full Text Available RESEARCH QUESTION What are the socio-demographic profile trends of Organophosphorus poisoning in Uttar Pradesh. DESIGN Prospective study; Interview technique. SAMPLE SIZE A total of 41 cases of OP poisoning were studied. All the information was recorded on a specially prepared Performa which included age, sex, duration of poisoning, amount of poisoning and way of poisoning. RESULT In this study 85% patients belonged to 15 years’ to 30 years’ age group, most of them 60.9% were female patients; 65.9% patients belonged to rural areas and 34.1% patients belonged to urban areas; 51.2% patients were admitted to our side with complaint of organophosphate poisoning within 12 hours; 41.5% patients were unable to tell the amount of poisoning they exposed; 24.4% had just exposed or taken less than 5 grams of poison and 34.1% had taken the poisoning more than 5 grams. Most of the patients, 78.6% had taken organophosphate for suicidal purpose and 21.4% patients were exposed to poison accidentally. Ratio of suicidal to accidental poisoning in rural areas is 2.4:1 and in urban areas is 3.7:1.

  1. Toxicology of organophosphorus compounds in view of an increasing terrorist threat.

    Science.gov (United States)

    Worek, Franz; Wille, Timo; Koller, Marianne; Thiermann, Horst

    2016-09-01

    The implementation of the Chemical Weapon Convention (CWC), prohibiting the development, production, storage and use of chemical weapons by 192 nations and the ban of highly toxic OP pesticides, especially class I pesticides according to the WHO classification, by many countries constitutes a great success of the international community. However, the increased interest of terrorist groups in toxic chemicals and chemical warfare agents presents new challenges to our societies. Almost seven decades of research on organophosphorus compound (OP) toxicology was mainly focused on a small number of OP nerve agents despite the fact that a huge number of OP analogues, many of these agents having comparable toxicity to classical nerve agents, were synthesized and published. Only limited physicochemical, toxicological and medical information on nerve agent analogues is available in the open literature. This implies potential gaps of our capabilities to detect, to decontaminate and to treat patients if nerve agent analogues are disseminated and may result in inadequate effectiveness of newly developed countermeasures. In summary, our societies may face new, up to now disregarded, threats by toxic OP which calls for increased awareness and appropriate preparedness of military and civilian CBRN defense, a broader approach for new physical and medical countermeasures and an integrated system of effective detection, decontamination, physical protection and treatment.

  2. In vitro human skin penetration model for organophosphorus compounds with different physicochemical properties.

    Science.gov (United States)

    Thors, L; Koch, B; Koch, M; Hägglund, L; Bucht, A

    2016-04-01

    A flow-through diffusion cell was validated for in vitro human epidermal penetration studies of organophosphorus compounds (OPCs) applied by infinite dosing. By testing OPCs with similar molecular weight but different physicochemical properties, it was shown that hydrophilic and lipophilic properties are major determinants for the penetration rate. Lipophilic OPCs displayed maximum cumulative penetration in the 20-75% agent concentration range whereas the hydrophilic OPCs displayed maximum cumulative penetration at 10 or 20% agent concentration. Low penetration was observed for all agents at 1% agent concentration or when applied as neat agents. The impact of the receptor solution composition was evaluated by comparing the penetration using receptor solutions of different ratios of ethanol and water. For diluted OPCs, a high concentration of ethanol in the receptor solution significantly increased the penetration compared to lower concentrations. When OPCs were applied as neat agents, the composition of the receptor solution only affected the penetration for one of four tested compounds. In conclusion, the flow-through diffusion cell was useful for examining the penetration of OPCs through the epidermal membrane. It was also demonstrated that the penetration rates of OPCs are strongly influenced by dilution in water and the receptor fluid composition.

  3. Sensitive spectrophotometric methods for determination of some organophosphorus pesticides in vegetable samples

    Directory of Open Access Journals (Sweden)

    MAGDA A. AKL

    2010-03-01

    Full Text Available Three rapid, simple, reproducible and sensitive spectrophotometric methods (A, B and C are described for the determination of two organophosphorus pesticides, (malathion and dimethoate in formulations and vegetable samples. The methods A and B involve the addition of an excess of Ce4+ into sulphuric acid medium and the determination of the unreacted oxidant by decreasing the red color of chromotrope 2R (C2R at a suitable lmax = 528 nm for method A, or a decrease in the orange pink color of rhodamine 6G (Rh6G at a suitable lmax = = 525 nm. The method C is based on the oxidation of malathion or dimethoate with the slight excess of N-bromosuccinimide (NBS and the determination of unreacted oxidant by reacting it with amaranth dye (AM in hydrochloric acid medium at a suitable lmax = 520 nm. A regression analysis of Beer-Lambert plots showed a good correlation in the concentration range of 0.1-4.2 μg mL−1. The apparent molar absorptivity, Sandell sensitivity, the detection and quantification limits were calculated. For more accurate analysis, Ringbom optimum concentration ranges are 0.25-4.0 μg mL−1. The developed methods were successfully applied to the determination of malathion, and dimethoate in their formulations and environmental vegetable samples.

  4. In vivo tracing of organophosphorus pesticides in cabbage (Brassica parachinensis) and aloe (Barbadensis).

    Science.gov (United States)

    Qiu, Junlang; Chen, Guosheng; Zhou, Hong; Xu, Jianqiao; Wang, Fuxin; Zhu, Fang; Ouyang, Gangfeng

    2016-04-15

    In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography-mass spectrometry (GC-MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC-MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production.

  5. Simulated solar light phototransformation of organophosphorus azinphos methyl at the surface of clays and goethite.

    Science.gov (United States)

    Menager, Matthieu; Sarakha, Mohamed

    2013-01-15

    The photochemical behavior of the pesticide azinphos methyl at the surface of clays (kaolinite, bentonite) and goethite was studied using Suntest setup (λ > 300 nm). The quantum yield on the clays was found to be roughly three times lower than that in aqueous solution. However, the photochemical efficiency was much higher at the surface of goethite owing to its photocatalytic activity through the hydroxyl radical production. The added humic substances on kaolonite show an inhibition of azinphos methyl degradation while the incorporation of iron(III) aquacomplexes leads to an important increase of the disappearance together with the formation of iron(II). Hydroxyl radical species were found to be formed either by excitation of goethite or clays. The goethite support acts as a more efficient catalyst for the formation of these reactive oxygen species. The photodecomposition reactions observed were (i) hydrolysis process leading to the formation of benzotriazone and the oxidation of the P = S bond giving rise to the formation of the oxon derivative, and (ii) homolytic cleavage of the N-C and C-S bonds of the organophosphorus bridge leading to the formation of dimers that appear to be specific to the irradiation at the surface of solid supports since they were not observed when the irradiation was performed in aqueous media: a statement that is related to the presence of aggregates at the surface of solid supports.

  6. Distribution of organophosphorus flame retardants in sediments from the Pearl River Delta in South China.

    Science.gov (United States)

    Tan, Xiao-Xin; Luo, Xiao-Jun; Zheng, Xiao-Bo; Li, Zong-Rui; Sun, Run-Xia; Mai, Bi-Xian

    2016-02-15

    Twelve organophosphorus flame retardants (PFRs) were identified in the sediments and the sediment core collected from the rivers and the estuary in the Pearl River Delta, with the aim of investigating their spatial and vertical distributions. The concentrations of PFRs ranged from 8.3 to 470 ng/g dry weight with high levels of PFRs in the urban area and the e-waste recycling region. Generally, TPhP, TCPP, TEHP, TCEP, and TBEP were the dominant compounds of the PFRs, the composition of which varied across the different regions, reflecting the different sources of PFRs. In the estuary, the PFRs mainly derived from the Xijiang River and the Shunde sections. Increased concentrations of halogen-containing PFRs have been observed in the upper layers of the sediment core. Conversely, relatively high concentrations of halogen-free PFRs were observed in the lower layers of the sediment core, indicating different usage patterns or environmental behaviors between the halogen and the non-halogen PFRs in the study area.

  7. Study on the toxic effect of the mixture of organophosphorus pesticide on perinatal rats

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To observe the toxic effect of the mixture of organophosphorus pesticide (MOP) on maternal rats and on the growth and development of their offspring. Methods Totally 40 Sprague-Dawley pregnant rats were randomly divided into three MOP dose groups and one control to which their offspring would be assigned. The experimental dosage of MOP and distilled water were administered orally starting on gestation day 15 and continued for 35 days. The physical development indices and the learning ability of F1 rats were measured during lactation. The pathological changes of uterus and liver of F0 rats were observed after weaning, while the weight ratio of uterus and some viscera to body of the F1 were examined. Results There were obvious changes of uterus and liver in the high-dose group of F0. The body-weight accretion of the F1 in high-dose group was obviously lower than that in control group (P<0.05). Some of the MOP F1 rats development indices delayed significantly (P<0.05), the learning ability decreased obviously, and the time of setting up memory prolonged (P<0.05). The ratio of the uterus weight to body-weight in the F1 MOP groups was significantly higher than that in control group (P<0.05). Conclusion The experiment doses of MOP are proved to have significant reproductive toxicity on perinatal rats.

  8. Organophosphorus flame retardants (PFRs) in human breast milk from several Asian countries.

    Science.gov (United States)

    Kim, Joon-Woo; Isobe, Tomohiko; Muto, Mamoru; Tue, Nguyen Minh; Katsura, Kana; Malarvannan, Govindan; Sudaryanto, Agus; Chang, Kwang-Hyeon; Prudente, Maricar; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke

    2014-12-01

    In this study, the concentrations of 10 organophosphorus flame retardants (PFRs) were determined in 89 human breast milk samples collected from Japan, the Philippines and Vietnam. Among the targeted PFRs, tris(2-chloroexyl) phosphate (TCEP) and triphenyl phosphate (TPHP) were the predominant compounds and were detected in more than 60% of samples in all three countries. The concentrations of PFRs in human breast milk were significantly higher (p<0.05) in the Philippines (median 70 ng g(-1) lipid wt.) than those in Japan (median 22 ng g(-1) lipid wt.) and Vietnam (median 10 ng g(-1) lipid wt.). The present results suggest that the usage of products containing PFRs in the Philippines is higher than those of Japan and Vietnam. Comparing with a previous literature survey in Sweden, the levels of PFRs in human breast milk from the Philippines were 1.5-2 times higher, whereas levels in Japan and Vietnam were 4-20 times lower, suggesting that these differences might be due to their variation in the usage of flame-retarded products utilized in each country. When daily intake of PFRs to infants via human breast milk was estimated, some individuals accumulated tris(2-butoxyethyl) phosphate (TBOEP) and TCEP were close to reference dose (RfD). This is the first report to identify PFRs in human breast milk samples from Asian countries.

  9. Organophosphorus flame retardants in house dust from the Philippines: occurrence and assessment of human exposure.

    Science.gov (United States)

    Kim, Joon-Woo; Isobe, Tomohiko; Sudaryanto, Agus; Malarvannan, Govindan; Chang, Kwang-Hyeon; Muto, Mamoru; Prudente, Maricar; Tanabe, Shinsuke

    2013-02-01

    The use of organophosphorus flame retardants (PFRs) as flame retardants and plasticizers has increased due to the ban on common polybrominated diphenyl ether mixtures. However, only limited information on PFR contamination is available so far from Southeast Asia. In the present study, residual levels of PFRs in house dust and exposure through dust ingestion were investigated in the Philippines. House dust samples (n = 37) were collected from Malate (residential area) and Payatas (municipal dumping area) in the Philippines and analyzed using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry. Among the targeted seven PFRs, triphenyl phosphate (TPP) was the predominant compound. Median levels of ΣPFRs in Malate (530 ng/g) were two times higher (p < 0.05) than in Payatas (240 ng/g). The estimated daily intake of PFRs in the Philippines (of areas studied) via house dust ingestion was below the guideline values. House dust may be an important contributor in the overall exposure of humans to TPP even when considering dietary sources. To our knowledge, this is a first report on PFR contamination in house dust from developing country. PFRs were ubiquitously detected in the home environments in the Philippines. Although estimated exposure levels through dust ingestion were below the guideline, it was suggested that toddlers are at higher risk. Therefore, further investigations to understand the behavior of PFRs in house and other microenvironments and overall exposure pathways for the country's populace to PFRs are necessary.

  10. Repeated exposure to sublethal doses of the organophosphorus compound VX activates BDNF expression in mouse brain.

    Science.gov (United States)

    Pizarro, Jose M; Chang, Wenling E; Bah, Mariama J; Wright, Linnzi K M; Saviolakis, George A; Alagappan, Arun; Robison, Christopher L; Shah, Jinesh D; Meyerhoff, James L; Cerasoli, Douglas M; Midboe, Eric G; Lumley, Lucille A

    2012-04-01

    The highly toxic organophosphorus compound VX [O-ethyl S-[2-(diisopropylamino)ethyl]methylphosphonate] is an irreversible inhibitor of the enzyme acetylcholinesterase (AChE). Prolonged inhibition of AChE increases endogenous levels of acetylcholine and is toxic at nerve synapses and neuromuscular junctions. We hypothesized that repeated exposure to sublethal doses of VX would affect genes associated with cell survival, neuronal plasticity, and neuronal remodeling, including brain-derived neurotrophic factor (BDNF). We examined the time course of BDNF expression in C57BL/6 mouse brain following repeated exposure (1/day × 5 days/week × 2 weeks) to sublethal doses of VX (0.2 LD(50) and 0.4 LD(50)). BDNF messenger RNA expression was significantly (p VX exposure. BDNF protein expression, however, was only increased in the CA3 region of the hippocampus. Whether increased BDNF in response to sublethal doses of VX exposure is an adaptive response to prevent cellular damage or a precursor to impending brain damage remains to be determined. If elevated BDNF is an adaptive response, exogenous BDNF may be a potential therapeutic target to reduce the toxic effects of nerve agent exposure.

  11. Toxicogenomic studies of human neural cells following exposure to organophosphorus chemical warfare nerve agent VX.

    Science.gov (United States)

    Gao, Xiugong; Lin, Hsiuling; Ray, Radharaman; Ray, Prabhati

    2013-05-01

    Organophosphorus (OP) compounds represent an important group of chemical warfare nerve agents that remains a significant and constant military and civilian threat. OP compounds are considered acting primarily via cholinergic pathways by binding irreversibly to acetylcholinesterase, an important regulator of the neurotransmitter acetylcholine. Many studies over the past years have suggested that other mechanisms of OP toxicity exist, which need to be unraveled by a comprehensive and systematic approach such as genome-wide gene expression analysis. Here we performed a microarray study in which cultured human neural cells were exposed to 0.1 or 10 μM of VX for 1 h. Global gene expression changes were analyzed 6, 24, and 72 h post exposure. Functional annotation and pathway analysis of the differentially expressed genes has revealed many genes, networks and canonical pathways that are related to nervous system development and function, or to neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, and Parkinson's disease. In particular, the neuregulin pathway impacted by VX exposure has important implications in many nervous system diseases including schizophrenia. These results provide useful information valuable in developing suitable antidotes for more effective prevention and treatment of, as well as in developing biomarkers for, VX-induced chronic neurotoxicity.

  12. 绍兴市2006至2011年急性农药中毒分析%The characteristics and trends of acute pesticide poisoning of Shaoxing in 2006 to 2011

    Institute of Scientific and Technical Information of China (English)

    蒋国钦; 连灵君; 王春辉; 李明; 王纪刚; 潘南燕; 王莎莎

    2013-01-01

    cases were missed,accounting for 2.1% (44/2068) of all cases.Among the 2024 cases,119 (5.9%) died; the fatality rates of productive poisoning and unproductive poisoning were 1.0% (3/289) and 6.7% (116/1735),respectively.The reported cases included 1038 (51.3%) females and 986 (48.7%) males,and there were no significant differences in the ratio between male and female cases of acute pesticide poisoning from 2006 to 2011 (x2=9.16,P=0.10).The 2024 cases had a mean age of 47.0±18.7 years; the male cases had a significantly higher mean age than the female cases (50.7±19.0 vs 43.4±17.8 years,t=9.01,P<0.001).Among the 2024 cases,289 (14.3%) suffered productive poisoning,and 1735 (85.7%) suffered unproductive poisoning.In the 986 male cases,219 (22.2%) suffered productive poisoning; in the 1038 female cases,968 (93.3%) suffered unproductive poisoning.The pesticides that caused poisoning included insecticide (86.7%,1754/2024),herbicide (5.1%,104/2024),rodenticide (3.6%,72/2024),and bactericide,mixed preparation,biochemical pesticides,and other four categories of pesticides (4.6%,94/2024); of the 1754 cases caused by insecticide,1455 (83.0%) were attributed to organophosphorus insecticide.Conclusion The incidence of unproductive acute pesticide poisoning is high in Shaoxing,and it mainly affects females.Most cases of acute pesticide poisoning are aged 30~60 years.Insecticide is the main cause of poisoning.It is necessary to enhance health knowledge popularization and safety management of pesticides.

  13. A Locomotor Deficit Induced by Sublethal Doses of Pyrethroid and Neonicotinoid Insecticides in the Honeybee Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Mercédès Charreton

    Full Text Available The toxicity of pesticides used in agriculture towards non-targeted organisms and especially pollinators has recently drawn the attention from a broad scientific community. Increased honeybee mortality observed worldwide certainly contributes to this interest. The potential role of several neurotoxic insecticides in triggering or potentiating honeybee mortality was considered, in particular phenylpyrazoles and neonicotinoids, given that they are widely used and highly toxic for insects. Along with their ability to kill insects at lethal doses, they can compromise survival at sublethal doses by producing subtle deleterious effects. In this study, we compared the bee's locomotor ability, which is crucial for many tasks within the hive (e.g. cleaning brood cells, feeding larvae…, before and after an acute sublethal exposure to one insecticide belonging to the two insecticide classes, fipronil and thiamethoxam. Additionally, we examined the locomotor ability after exposure to pyrethroids, an older chemical insecticide class still widely used and known to be highly toxic to bees as well. Our study focused on young bees (day 1 after emergence since (i few studies are available on locomotion at this stage and (ii in recent years, pesticides have been reported to accumulate in different hive matrices, where young bees undergo their early development. At sublethal doses (SLD48h, i.e. causing no mortality at 48 h, three pyrethroids, namely cypermethrin (2.5 ng/bee, tetramethrin (70 ng/bee, tau-fluvalinate (33 ng/bee and the neonicotinoid thiamethoxam (3.8 ng/bee caused a locomotor deficit in honeybees. While the SLD48h of fipronil (a phenylpyrazole, 0.5 ng/bee had no measurable effect on locomotion, we observed high mortality several days after exposure, an effect that was not observed with the other insecticides. Although locomotor deficits observed in the sublethal range of pyrethroids and thiamethoxam would suggest deleterious effects in the field

  14. A Locomotor Deficit Induced by Sublethal Doses of Pyrethroid and Neonicotinoid Insecticides in the Honeybee Apis mellifera.

    Science.gov (United States)

    Charreton, Mercédès; Decourtye, Axel; Henry, Mickaël; Rodet, Guy; Sandoz, Jean-Christophe; Charnet, Pierre; Collet, Claude

    2015-01-01

    The toxicity of pesticides used in agriculture towards non-targeted organisms and especially pollinators has recently drawn the attention from a broad scientific community. Increased honeybee mortality observed worldwide certainly contributes to this interest. The potential role of several neurotoxic insecticides in triggering or potentiating honeybee mortality was considered, in particular phenylpyrazoles and neonicotinoids, given that they are widely used and highly toxic for insects. Along with their ability to kill insects at lethal doses, they can compromise survival at sublethal doses by producing subtle deleterious effects. In this study, we compared the bee's locomotor ability, which is crucial for many tasks within the hive (e.g. cleaning brood cells, feeding larvae…), before and after an acute sublethal exposure to one insecticide belonging to the two insecticide classes, fipronil and thiamethoxam. Additionally, we examined the locomotor ability after exposure to pyrethroids, an older chemical insecticide class still widely used and known to be highly toxic to bees as well. Our study focused on young bees (day 1 after emergence) since (i) few studies are available on locomotion at this stage and (ii) in recent years, pesticides have been reported to accumulate in different hive matrices, where young bees undergo their early development. At sublethal doses (SLD48h, i.e. causing no mortality at 48 h), three pyrethroids, namely cypermethrin (2.5 ng/bee), tetramethrin (70 ng/bee), tau-fluvalinate (33 ng/bee) and the neonicotinoid thiamethoxam (3.8 ng/bee) caused a locomotor deficit in honeybees. While the SLD48h of fipronil (a phenylpyrazole, 0.5 ng/bee) had no measurable effect on locomotion, we observed high mortality several days after exposure, an effect that was not observed with the other insecticides. Although locomotor deficits observed in the sublethal range of pyrethroids and thiamethoxam would suggest deleterious effects in the field, the case of

  15. Further insecticidal activities of essential oils from Lippia sidoides and Croton species against Aedes aegypti L.

    Science.gov (United States)

    de Lima, Glauber Pacelli Gomes; de Souza, Terezinha Maria; de Paula Freire, Gabrielle; Farias, Davi Felipe; Cunha, Arcelina Pacheco; Ricardo, Nágila Maria Pontes Silva; de Morais, Selene Maia; Carvalho, Ana Fontenele Urano

    2013-05-01

    This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg mL(-1), larvicidal activity with LC50 ranging from 25.5 to 94.6 μg mL(-1), and pupicidal action with PC50 ranging from 276.8 to over 500 μg mL(-1). Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg mL(-1), respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50 > 6,000 mg.kg(-1)) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg(-1), respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals.

  16. Ternary toxicological interactions of insecticides, herbicides, and a heavy metal on the earthworm Eisenia fetida.

    Science.gov (United States)

    Wang, Yanhua; Chen, Chen; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang

    2015-03-01

    The combined toxicities of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor), and a heavy metal (cadmium) have been examined using the acute toxicity test on the earthworm. With a concentration of 2.75 mg/kg being lethal for 50% of the organisms, imidacloprid exhibited the highest acute toxicity toward the earthworm Eisenia fetida. Toxicological interactions of these chemicals in ternary mixtures were studied using the combination-index (CI) equation method. Twenty-one ternary mixtures exhibited various interactive effects, in which 11 combinations showed synergistic effects, four led to dual synergistic/additive behaviors, one exhibited an additive effect, and five showed increasing antagonism within the entire range of effects. The CI method was compared with the classical models of concentration addition and independent action, and it was found that the CI method could accurately predict combined toxicity of the chemicals studied. The predicted synergism in the majority of the mixtures, especially at low-effect levels, might have implications in the real terrestrial environment.

  17. Role of cytochrome P450s in insecticide resistance: impact on the control of mosquito-borne diseases and use of insecticides on Earth.

    Science.gov (United States)

    David, Jean-Philippe; Ismail, Hanafy Mahmoud; Chandor-Proust, Alexia; Paine, Mark John Ingraham

    2013-02-19

    The fight against diseases spread by mosquitoes and other insects has enormous environmental, economic and social consequences. Chemical insecticides remain the first line of defence but the control of diseases, especially malaria and dengue fever, is being increasingly undermined by insecticide resistance. Mosquitoes have a large repertoire of P450s (over 100 genes). By pinpointing the key enzymes associated with insecticide resistance we can begin to develop new tools to aid the implementation of control interventions and reduce their environmental impact on Earth. Recent technological advances are helping us to build a functional profile of the P450 determinants of insecticide metabolic resistance in mosquitoes. Alongside, the cross-responses of mosquito P450s to insecticides and pollutants are also being investigated. Such research will provide the means to produce diagnostic tools for early detection of P450s linked to resistance. It will also enable the design of new insecticides with optimized efficacy in different environments.

  18. Short and long-term effects of three neurotoxic insecticides on biological and behavioural attributes of the orb-web spider Alpaida veniliae (Araneae, Araneidae): implications for IPM programs.

    Science.gov (United States)

    Benamú, Marco A; Schneider, Marcela I; González, Alda; Sánchez, Norma E

    2013-09-01

    Soybean pest control in Argentina is done just by chemical control using broad-spectrum pesticides. Alpaida veniliae (Araneae, Araneidae) is one of the most abundant spider species of the orb web weaver guild in soybean, and it is considered a very important polyphagous predator, attacking different insects' families. The objective of this study was to determine if neurotoxic insecticides commonly used in soybean crops and a new active ingredient registered in Argentina (spinosad) adversely affected survival, prey consumption, mating behaviour, web building and reproductive capacity of A. veniliae females, under standard laboratory conditions. Spinosad was the most harmful insecticide due to high acute toxicity, even at lower concentrations than those registered for its field use and for its sublethal effects also. Cypermethrin caused several sublethal effects although its acute toxicity on spider was lower than other insecticides. It reduced prey consumption, affected web building, caused abnormalities in eggs sacs and decreased drastically the fecundity and fertility at sublethal concentrations. Endosulfan did not reduce prey consumption but it affected web building, caused abnormalities in eggs sacs and egg masses, and decreased the fecundity and fertility. Spinosad was also the compound with the most drastic effect on web building, it did not reduce prey consumption and fecundity, but fertility was reduced and abnormalities in egg sacs and egg masses were observed. The use of these insecticides in IPM programs according to their potential toxicity on spider communities is discussed.

  19. Acute cholecystitis

    OpenAIRE

    Halpin, Valerie

    2014-01-01

    Acute cholecystitis causes unremitting right upper quadrant pain, anorexia, nausea, vomiting, and fever, and if untreated can lead to perforations, abscess formation, or fistulae. About 95% of people with acute cholecystitis have gallstones.It is thought that blockage of the cystic duct by a gallstone or local inflammation can lead to acute cholecystitis, but we don't know whether bacterial infection is also necessary.

  20. Investigation of the Insecticide Seed Dressing on the Sugar Beet

    Directory of Open Access Journals (Sweden)

    Jasminka Igrc Barčić

    2000-06-01

    Full Text Available The results of three year trials with various sugar beet seed treatments on the most important sugar beet pests, wireworms, flea beetles, sugar beet weevil and aphids are presented. The task of the investigation was to establish whether or not the sugar beet seed should be treated with insecticides and when granulars should be applied. In threeyear investigations 6 trials on different localities were carried out. Gaucho 70WS, Montur 190 FS, Geocid ST 35, Carbofuran 500 FS and a combination of Geocid ST 35 and Geocid G-5 were applied. The results showed that the imidacloprid seed treatment was satisfactory efficient on wireworms ensuring 20-42% more plants than on untreated plots. The efficacy of all treatments on the flea beetles was sufficient: Gaucho 70 WS 63-70%, the combined carbofuran treatment 65-67%, Geocid ST 35 54-55% and Montur 190 FS 52-55%. Therefore on imidacloprid and carbofuran treated crops the foliar treatment against flea beetles is mostly unnecassary. Insecticides based on imidacloprid showed a very good efficacy on aphids until 64 days after the sowing time with a somewhat longer residual action than the standard carbofuran treatments. All investigated insecticides were not satisfactorily efficient against sugar beet weevil. The seed dressing with a systemic insecticide is a justified measure. But, if the attack of wirevorms is strong or if a positive sugar beet weevil forecast is present, granulars shoud be applied additionaly.

  1. Seed coating with a neonicotinoid insecticide negatively affects wild bees.

    Science.gov (United States)

    Rundlöf, Maj; Andersson, Georg K S; Bommarco, Riccardo; Fries, Ingemar; Hederström, Veronica; Herbertsson, Lina; Jonsson, Ove; Klatt, Björn K; Pedersen, Thorsten R; Yourstone, Johanna; Smith, Henrik G

    2015-05-07

    Understanding the effects of neonicotinoid insecticides on bees is vital because of reported declines in bee diversity and distribution and the crucial role bees have as pollinators in ecosystems and agriculture. Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees. The moratorium has been criticized for being based on weak evidence, particularly because effects have mostly been measured on bees that have been artificially fed neonicotinoids. Thus, the key question is how neonicotinoids influence bees, and wild bees in particular, in real-world agricultural landscapes. Here we show that a commonly used insecticide seed coating in a flowering crop can have serious consequences for wild bees. In a study with replicated and matched landscapes, we found that seed coating with Elado, an insecticide containing a combination of the neonicotinoid clothianidin and the non-systemic pyrethroid β-cyfluthrin, applied to oilseed rape seeds, reduced wild bee density, solitary bee nesting, and bumblebee colony growth and reproduction under field conditions. Hence, such insecticidal use can pose a substantial risk to wild bees in agricultural landscapes, and the contribution of pesticides to the global decline of wild bees may have been underestimated. The lack of a significant response in honeybee colonies suggests that reported pesticide effects on honeybees cannot always be extrapolated to wild bees.

  2. GABA receptor subunit composition relative to insecticide potency and selectivity.

    Science.gov (United States)

    Ratra, G S; Casida, J E

    2001-07-01

    Three observations on the 4-[(3)H]propyl-4'-ethynylbicycloorthobenzoate ([(3)H]EBOB) binding site in the gamma-aminobutyric acid (GABA) receptor indicate the specific target for insecticide action in human brain and a possible mechanism for selectivity. First, from published data, alpha-endosulfan, lindane and fipronil compete for the [(3)H]EBOB binding site with affinities of 0.3--7 nM in both human recombinant homooligomeric beta 3 receptors and housefly head membranes. Second, from structure-activity studies, including new data, GABAergic insecticide binding potency on the pentameric receptor formed from the beta 3 subunit correlates well with that on the housefly receptor (r=0.88, n=20). This conserved inhibitor specificity is consistent with known sequence homologies in the housefly GABA receptor and the human GABA(A) receptor beta 3 subunit. Third, as mostly new findings, various combinations of alpha 1, alpha 6, and gamma 2 subunits coexpressed with a beta 1 or beta 3 subunit confer differential insecticide binding sensitivity, particularly to fipronil, indicating that subunit composition is a major factor in insecticide selectivity.

  3. Control of rugose spiraling whitefly using biological insecticides, 2014

    Science.gov (United States)

    The objective of this study was to evaluate the efficacy of selected biological insecticides against a new invasive whitefly pest, Aleurodicus rugioperculatus Martin, in white bird of paradise under field condition. The trial was conducted at United States Horticultural Research Laboratory in Fort P...

  4. Domains of Bacillus thuringiensis crystal proteins involved in insecticidal activity

    NARCIS (Netherlands)

    Bosch, H.J.; Schipper, B.; Kleij, van der H.; Maagd, de R.A.; Stiekema, W.J.

    1994-01-01

    The expected increase in application of Bacillus thuringiensis (Bt) in crop protection makes it necessary to anticipate the development of Bt-resistant insects. To safeguard the long-term use of Bt-based insecticides, we studied the mode of action of Bt crystal proteins. CryIA(b), CryIC and CryIE ar

  5. Insecticidal Activity of Piperine Isolated from Piper sarmentosum

    Institute of Scientific and Technical Information of China (English)

    Feng; Gang; Ye; Huochun; Yuan; Enlin; Zhang; Jing; Yan; Chao; Jin; Qian; Peng; Zhengqiang; Fu; Yue-guan

    2014-01-01

    In order to clarify the insecticidal active ingredients of Piper sarmentosum,one active ingredient was isolated from ethanol extract of P. sarmentosum by bioassay-guided fractionation method. Its chemical structures were identified to be piperine by MS,1H NMR,13C NMR. The insecticidal activity of piperine and ethanol extract of P. sarmentosum against Aleurodicus dispels Russell were tested by leaf dip method. The results showed that piperine and ethanol extract of P. sarmentosum exhibited strong insecticidal activity against adults and nymphs of A. dispels; LC50values against adults were 28. 59 and 224. 31 mg/L,and LC50values against nymphs were 65. 91 and 336. 68 mg/L,respectively. There was no significant difference between piperine and azadirachtin against adults and nymphs of A.dispels. Therefore,piperine might be one of the main insecticidal ingredients of P. sarmentosum. In addition,piperine and ethanol extract showed ovicidal activity with different mode of action,piperine reduced the survival rate of newly hatched nymphs while ethanol extract impacted hatch of eggs.

  6. Oral insecticidal activity of plant-associated pseudomonads.

    Science.gov (United States)

    Ruffner, Beat; Péchy-Tarr, Maria; Ryffel, Florian; Hoegger, Patrik; Obrist, Christian; Rindlisbacher, Alfred; Keel, Christoph; Maurhofer, Monika

    2013-03-01

    Biocontrol pseudomonads are most known to protect plants from fungal diseases and to increase plant yield, while intriguing aspects on insecticidal activity have been discovered only recently. Here, we demonstrate that Fit toxin producing pseudomonads, in contrast to a naturally Fit-deficient strain, exhibit potent oral activity against larvae of Spodoptera littoralis, Heliothis virescens and Plutella xylostella, all major insect pests of agricultural crops. Spraying plant leaves with suspensions containing only 1000 Pseudomonas cells per ml was sufficient to kill 70-80% of Spodoptera and Heliothis larvae. Monitoring survival kinetics and bacterial titres in parallel, we demonstrate that Pseudomonas fluorescens CHA0 and Pseudomonas chlororaphis PCL1391, two bacteria harbouring the Fit gene cluster colonize and kill insects via oral infection. Using Fit mutants of CHA0 and PCL1391, we show that production of the Fit toxin contributes substantially to oral insecticidal activity. Furthermore, the global regulator GacA is required for full insecticidal activity. Our findings demonstrate the lethal oral activity of two root-colonizing pseudomonads so far known as potent antagonists of fungal plant pathogens. This adds insecticidal activity to the existing biocontrol repertoire of these bacteria and opens new perspectives for applications in crop pest control and in research on their ecological behaviour.

  7. Insecticide resistance in bedbugs in Thailand and laboratory evaluation of insecticides for the control of Cimex hemipterus and Cimex lectularius (Hemiptera: Cimicidae).

    Science.gov (United States)

    Tawatsin, Apiwat; Thavara, Usavadee; Chompoosri, Jakkrawarn; Phusup, Yutthana; Jonjang, Nisarat; Khumsawads, Chayada; Bhakdeenuan, Payu; Sawanpanyalert, Pathom; Asavadachanukorn, Preecha; Mulla, Mir S; Siriyasatien, Padet; Debboun, Mustapha

    2011-09-01

    Bedbugs are found in many countries around the world, and in some regions they are resistant to numerous insecticides. This study surveyed bedbugs in Thailand and determined their resistance to insecticides. The surveys were carried out in six provinces that attract large numbers of foreign tourists: Bangkok, Chonburi, Chiang Mai, Ubon Ratchathani, Phuket, and Krabi. Bedbugs were collected from hotels and colonized in the laboratory to evaluate their resistance to insecticides. Cimex hemipterus (F.) was found in some hotels in Bangkok, Chonburi, Phuket, and Krabi, whereas Cimex lectularius L. was found only in hotels in Chiang Mai. No bedbugs were found in Ubon Ratchathani. The colonized bedbugs showed resistance to groups of insecticides, including organochlorines (dichlorodiphenyl trichloroethane, dieldrin), carbamates (bendiocarb, propoxur), organophosphates (malathion, fenitrothion), and pyrethroids (cyfluthrin, deltamethrin, permethrin, lambda-cyhalothrin, etofenprox) in tests using World Health Organization insecticide-impregnated papers. The new insecticides imidacloprid (neonicotinoid group), chlorfenapyr (pyrrole group), and fipronil (phenylpyrazole group) were effective against the bedbugs; however, organophosphate (diazinon), carbamates (fenobucarb, propoxur), and pyrethroids (bifenthrin, cypermethrin, esfenvalerate, etofenprox) were ineffective. Aerosols containing various pyrethroid insecticides with two to four different active ingredients were effective against the bedbugs. The results obtained from this study suggested that both species of bedbugs in Thailand have developed marked resistance to various groups of insecticides, especially those in the pyrethroid group, which are the most common insecticides used for pest control. Therefore, an integrated pest management should be implemented for managing bedbugs in Thailand.

  8. A Characterization of Carboxylesterases in Rat and Guinea Pig - Their Heterogeneity and Role in Detoxication of Organophosphorus Compounds

    Science.gov (United States)

    1993-09-01

    lipase (EC 3.1.1.23) 1221, in both 12. Berg T, Boman D and Segelen P0, Induction of EC and KC may serve to protect the liver by hydrolysis of...organophosphorus compounds. CarbE isoenzymes have been sepa- rated from lung, liver , plasma and small intestine of rat and guinea pig mainly by chromatofocusing...different tissues of rat and guinea pig 18 5.5 Heterogeneity of carboxylesterases in rat liver cells 20 6 CONCLUSIONS 20 References 21 Errata 27

  9. Quantitation of organophosphorus nerve agent metabolites in human urine using isotope dilution gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Driskell, W Jack; Shih, Ming; Needham, Larry L; Barr, Dana B

    2002-01-01

    An isotope dilution gas chromatography-tandem mass spectrometric (GC-MS-MS) method was developed for quantitating the urinary metabolites of the organophosphorus nerve agents sarin, soman, tabun (GA), VX, and GF. Urine samples were concentrated by codistillation with acetonitrile, derivatized by methylation with diazomethane, and analyzed by GC-MS-MS. The limits of detection were less than 4 microg/L for all the analytes except for the GA metabolite, which had a limit of detection of less than 20 microg/L.

  10. Analysis of Insecticides in Dead Wild Birds in Korea from 2010 to 2013.

    Science.gov (United States)

    Kim, Soohee; Park, Mi-Young; Kim, Hyo-Jin; Shin, Jin Young; Ko, Kyung Yuk; Kim, Dong-Gyu; Kim, MeeKyung; Kang, Hwan-Goo; So, ByungJae; Park, Sung-Won

    2016-01-01

    Wild birds are exposed to insecticides in a variety of ways, at different dose levels and via multiple routes, including ingestion of contaminated food items, and dermal, inhalation, preening, and embryonic exposure. Most poisoning by insecticides occurs as a result of misuse or accidental exposure, but intentional killing of unwanted animals also occurs. In this study, we investigated insecticides in the gastric contents of dead wild birds that were suspected to have died from insecticide poisoning based on necropsy. The wild birds were found dead in various regions and locations such as in mountains, and agricultural and urban areas. A total of 182 dead wild birds of 27 species were analyzed in this study, and insecticide residue levels were determined in 60.4% of the total samples analyzed. Monocrotophos and phosphamidon were the most common insecticides identified at rates of 50.0% and 30.7% of the insecticide-positive samples, respectively. Other insecticides identified in dead wild birds included organophosphorous, organochlorine and carbamate insecticides. However, there was limited evidence to conclusively establish the cause of death related to insecticides in this study. Nevertheless, considering the level of insecticide exposure, it is speculated that the exposure was mainly a result of accidental or intentional killing, and not from environmental residue.

  11. Changes in insecticide resistance of the rice striped stem borer (Lepidoptera: Crambidae).

    Science.gov (United States)

    Su, Jianya; Zhang, Zhenzhen; Wu, Min; Gao, Congfen

    2014-02-01

    Application of insecticides is the most important method to control Chilo suppressalis (Walker) (Lepidoptera: Crambidae), and continuous use of individual insecticides has driven the rapid development of insecticide resistance in C. suppressalis during the past 30 yr. Monitoring insecticide resistance provides information essential for integrated pest management. Insecticide resistance of field populations to monosultap, triazophos, chlorpyrifos, and abamectin in China was examined in 2010 and 2011. The results indicated that the resistance levels of 14 field populations to four insecticides were significantly different. Four populations showed moderate resistance, and other populations possessed low-level resistance or were susceptible to monosultap. Nine populations displayed an extremely high or a high level of resistance to triazophos, whereas four populations were sensitive to this agent. Five populations exhibited a low level of resistance to abamectin, while the others remained sensitive. When compared with historical data, resistance to monosultap and triazophos decreased significantly, and the percentage of populations with high-level or extremely high-level resistance was obviously reduced. By contrast, the resistance to abamectin increased slightly. The increasing and decreasing resistance levels reported in this study highlight the different evolutionary patterns of insecticide resistance in C. suppressalis. An overreliance on one or two insecticides may promote rapid development of resistance. Slow development of resistance to abamectin, which was used mainly in mixtures with other insecticides, implies that the use of insecticide mixtures may be an effective method to delay the evolution of resistance to insecticides.

  12. Aquatic life water quality criteria derived via the UC Davis method: I. Organophosphate insecticides.

    Science.gov (United States)

    Palumbo, Amanda J; Tenbrook, Patti L; Fojut, Tessa L; Faria, Isabel R; Tjeerdema, Ronald S

    2012-01-01

    A new methodology for deriving freshwater aquatic life water quality criteria,developed by the University of California Davis, was used to derive criteria for three organophosphate insecticides. The UC Davis methodology resulted in similar criteria to other accepted methods, and incorporated new approaches that enable criteria generation in cases where the existing USEPA guidance cannot be used.Acute and chronic water quality criteria were derived for chlorpyrifos (10 and 10 ng/L, respectively), diazinon (200 and 70 ng/L, respectively), and malathion(170 and 28 ng/L, respectively). For acute criteria derivation, Burr Type III SSDs were fitted to the chlorpyrifos and diazinon acute toxicity data sets while an alternative assessment factor procedure was used for malathion because that acute data set did not contain adequate species diversity to use a distribution.ACRs were used to calculate chronic criteria because there was a dearth of chronic data in all cases, especially for malathion, for which there was a lack of paired acute and chronic invertebrate data. Another alternate procedure enabled calculation of the malathion chronic criterion by combining a default ratio with the experimentally derived ratios. A review of the diazinon chronic criterion found it to be under protective of cladoceran species, so a more protective criterion was calculated using a lower distributional estimate. The acute and chronic data sets were assembled using a transparent and consistent system for judging the relevance and reliability of studies, and the individual study review notes are included.The resulting criteria are unique in that they were reviewed to ensure particular protection of sensitive and threatened and endangered species, and mixture toxicity is incorporated into criteria compliance for all three compounds.For chlorpyrifos and diazinon, the UCDM generated criteria similar to the long-standing USEPA (1985) method, with less taxa requirements, a more statistically

  13. Underpinning sustainable vector control through informed insecticide resistance management.

    Directory of Open Access Journals (Sweden)

    Edward K Thomsen

    Full Text Available BACKGROUND: There has been rapid scale-up of malaria vector control in the last ten years. Both of the primary control strategies, long-lasting pyrethroid treated nets and indoor residual spraying, rely on the use of a limited number of insecticides. Insecticide resistance, as measured by bioassay, has rapidly increased in prevalence and has come to the forefront as an issue that needs to be addressed to maintain the sustainability of malaria control and the drive to elimination. Zambia's programme reported high levels of resistance to the insecticides it used in 2010, and, as a result, increased its investment in resistance monitoring to support informed resistance management decisions. METHODOLOGY/PRINCIPAL FINDINGS: A country-wide survey on insecticide resistance in Zambian malaria vectors was performed using WHO bioassays to detect resistant phenotypes. Molecular techniques were used to detect target-site mutations and microarray to detect metabolic resistance mechanisms. Anopheles gambiae s.s. was resistant to pyrethroids, DDT and carbamates, with potential organophosphate resistance in one population. The resistant phenotypes were conferred by both target-site and metabolic mechanisms. Anopheles funestus s.s. was largely resistant to pyrethroids and carbamates, with potential resistance to DDT in two locations. The resistant phenotypes were conferred by elevated levels of cytochrome p450s. CONCLUSIONS/SIGNIFICANCE: Currently, the Zambia National Malaria Control Centre is using these results to inform their vector control strategy. The methods employed here can serve as a template to all malaria-endemic countries striving to create a sustainable insecticide resistance management plan.

  14. Mechanism and kinetics study on the OH-initiated oxidation of organophosphorus pesticide trichlorfon in atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Yuan; Zhang, Chenxi; Yang, Wenbo; Hu, Jingtian [Environment Research Institute, Shandong University, Jinan 250100 (China); Sun, Xiaomin, E-mail: sxmwch@sdu.edu.cn [Environment Research Institute, Shandong University, Jinan 250100 (China); State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy Of Science, Lanzhou 730000 (China)

    2012-03-01

    Trichlorfon [O,O-dimethyl-(2,2,2-trichloro-1-hydroxy-ethyl) phosphonate] (TCF) is a kind of widely used organophosphorus pesticides. In this paper, the mechanism and possible oxidation products for the OH-initiated reactions of TCF are studied at the MPWB1K/6-311 + G(3df,2p)//MPWB1K/6-31 + G(d,p) level. The study shows that H abstraction reaction from the CH{sub 3} group and the CH group as well as OH addition reaction to the P atom are energetically favorable for the reactions of TCF and the main products are (CH{sub 3}O){sub 2}POOH (P1), CCl{sub 3}CHOHPOOH(OCH{sub 3}) (P2), CH{sub 3}OPO{sub 2} (P3), CCl{sub 3}COPO(OCH{sub 3}){sub 2} (P6) and HCHO. On the basis of the quantum chemical information, the kinetic calculation is performed and the rate constants are calculated over a temperature range of 200-800 K using the transition state theory and canonical variational transition state theory with small-curvature tunneling effect. The Arrhenius formulas of rate constants with the temperature are fitted and the lifetimes of the reaction species in the troposphere are estimated according to the rate constants, which can provide helpful information for the model simulation study. - Highlights: Black-Right-Pointing-Pointer The H-abstracted reaction and OH addition reaction are favorable channels. Black-Right-Pointing-Pointer The Arrhenius formulas of rate constants with the temperature are fitted. Black-Right-Pointing-Pointer The rate constants of TCF relative to OH radical is 4.95 Multiplication-Sign 10{sup -15} cm{sup 3} molecule{sup -1} s{sup -1}.

  15. Phenylmethylsulfonyl fluoride, a potentiator of neuropathy, alters the interaction of organophosphorus compounds with soluble brain esterases.

    Science.gov (United States)

    Mangas, Iris; Vilanova, Eugenio; Estévez, Jorge

    2012-11-19

    Phenylmethylsulfonyl fluoride (PMSF) is a protease and esterase inhibitor that causes protection or potentiation/promotion of organophosphorus delayed neuropathy (OPIDN) depending on whether it is dosed before or after an inducer of delayed neuropathy. The molecular target of promotion has not yet been identified. Kinetic data of esterase inhibition were first obtained for PMSF with a soluble chicken brain fraction and then analyzed using a kinetic model with a multienzymatic system in which inhibition occurred with the simultaneous chemical hydrolysis of the inhibitor and ongoing inhibition (inhibition during the substrate reaction). The best fitting model was a model with resistant fraction, Eα (28%), and two sensitive enzymatic entities, Eβ (61%) and Eγ (11%), with I(50) at 20 min of 70 and 447 μM, respectively. The estimated constant of the chemical hydrolysis of PMSF was kh = 0.23 min(-1). Eα, which is sensitive to mipafox and resistant to PMSF, became less sensitive to mipafox when the preparation was preincubated with PMSF. Its Eα I(50) (30 min) of mipafox increased with the PMSF concentration used to preincubate it. Eγ is sensitive to both PMSF and mipafox, and after preincubation with PMSF, Eγ became less sensitive to mipafox and was totally resistant after preincubation with 10 μM PMSF or more. The sensitivity of Eα to paraoxon (I(50) 30 min from 9 to 11 nM) diminished after PMSF preincubation (I(50) 30 min 185 nM) and showed no spontaneous reactivation capacity. The nature of these interactions is unknown but might be due to covalent binding at sites other than the substrate catalytic center. Such interactions should be considered to interpret the potentiation/promotion phenomenon of PMSF and to understand the effects of multiple exposures to chemicals.

  16. Dose-response effects of atropine and HI-6 treatment of organophosphorus poisoning in guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Koplovitz, I.; Menton, R.; Matthews, C.; Shutz, M.; Nalls, C.

    1995-12-31

    H1-6 (1-2-hydrnxyiminomethyl-1 pyridino-3-(4-carbameyl- 1--pyddino)-2- oxaprnpane dichioride) has been evaluated as an oxime alternative to pralidoxime, and toxogonin in the treatment of organophosphorus (OP) poisoning. The dose response effects of atropine (ATR) and HI-6 were investigated to more fully explore the interaction of these compounds in the treatment of OP poisoning. ATR, HI-6 and various combinations of the two drugs were evaluated against lethal poisoning by soman (GD) and tabun (GA) in guinea pigs. The effect of adjunctive diazepam treatment on the efficacy of atropine and HI-6 against soman was also investigated. Animals of either sex were challenged s.c. with OP and treated i.m. 1 min later with ATR and/or HI-6. When used, diazepam was injected immediately after ATR+HI6. LD50s of each treatment were calculated from probit models based on 24-hour survival against 5 levels of nerve agent and 6 animals per challenge level. A protective index (PI) was calculated by dividing the nerve agent LD50 in the presence of treatment by the LD50 in the absence of treatment. Treatment with HI-6 alone had little effect on the toxicity of either OP. Treatment with ATR alone was more effective than HI-6 alone and was significantly more effective against soman than against tabun. When used in combination atropine and HI-6 had a strong synergistic effect against both agents. The dose of atropine used with HI-6 was critical in determining the efficacy of HI-6 against either agent. The slopes of the dose-lethality curves were minimally affected by the dose of ATR or HI-6. Adjunctive treatment with diazepam enhanced the efficacy of HI-6 and atropine against soman.

  17. Organophosphorus flame retardants and phthalate esters in indoor dust from different microenvironments: Bioaccessibility and risk assessment.

    Science.gov (United States)

    He, Ruiwen; Li, Yunzi; Xiang, Ping; Li, Chao; Zhou, Chunyang; Zhang, Shujun; Cui, Xinyi; Ma, Lena Q

    2016-05-01

    Incidental ingestion of indoor dust is an important pathway for human exposure to organophosphorus flame retardants (OPFRs) and phthalate esters (PAEs). However, little is known about their bioaccessibility in indoor dust. In this study, indoor dust samples were collected from houses, offices, public microenvironments (PMEs), and university dorms, and physiologically based extraction test (PBET) was used to measure the bioaccessibility of OPFRs and PAEs in these dust samples. Total concentrations of OPFRs in dust samples ranged from 0.01 to 63.2 μg g(-1), with significantly lower concentrations in dorm dust (median = 0.30 μg g(-1)) than those in houses (3.12), offices (5.94), and PMEs (11.6). Total PAEs ranged from 5.49 to 2161 μg g(-1) with significantly lower concentrations in dorm dust (379 μg g(-1)) than those in the other three types of dust (767, 515, and 731 μg g(-1)). When subject to PBET, the bioaccessibility of OPFRs ranged from 8.18% (triphenyl phosphate) to 54.5% (Tris(2-chloroisopropyl) phosphate) for OPFRs, and from 1.21% (di-2-ethylhexyl phthalate, DEHP) to 81.1% (dimethyl phthalate) for PAEs. Estimated exposure doses for adults and infants to OPFRs via dust ingestion were much lower than the reference doses (RfD), but intake dose of DEHP for infants was higher than the RfD of 20 μg kg(-1) d(-1). However, the DEHP intake dose did not exceed the RfD after incorporating bioaccessibility into risk assessment. Our data indicated the importance of considering contaminant bioaccessibility during risk assessment of indoor dust.

  18. Determination of Organophosphorus Pesticides in Soil by Dispersive Liquid–Liquid Microextraction and Gas Chromatography

    Science.gov (United States)

    Yang, Zhonghua; Liu, Yu; Liu, Donghui; Zhou, Zhiqiang

    2012-01-01

    In this article, a rapid and sensitive sample pretreatment technique for the determination of organophosphorus pesticides (OPPs) in soil samples is developed by using dispersive liquid–liquid microextraction (DLLME) combined with gas chromatography–flame photometric detection. Experimental conditions, including the kind of extraction and disperser solvent and their volumes, the extraction time, and the salt addition, are investigated, and the following experiment factors are used: 20 µL chlorobenzene as the extraction solvent; 1.0 mL acetonitrile as the disperser solvent; no addition of salt; and an extraction time of 1 min. Under the optimum conditions, the linearities for the three target OPPs (ethoprophos, chlorpyriphos, and profenofos) are obtained by five points in the concentration range of 2.5–1500 µg/kg, and three replicates are used for each point. Correlation coefficients vary from 0.9987 to 0.9997. The repeatability is tested by spiking soil samples at a concentration level of 5.0 µg/kg. The relative standard deviation (n = 3) varied between 2.0% and 6.6%. The limits of detection, based on a signal-to-noise ratio (S/N) of 3, range from 200 to 500 pg/g. This method is applied to the analysis of the spiked samples S1, S2, and S3, which are collected from the China Agriculture University's orchard, lawn, and garden, respectively. The recoveries for each target analyte are in the range between 87.9% and 108.0%, 87.4% and 108.0%, and 86.7% and 107.2%, respectively. PMID:22291051

  19. Zirconium(IV) functionalized magnetic nanocomposites for extraction of organophosphorus pesticides from environmental water samples.

    Science.gov (United States)

    Jiang, Li; Huang, Tengjun; Feng, Shun; Wang, Jide

    2016-07-22

    The widespread use of organophosphate pesticides (OPPs) in agriculture leads to residue accumulation in the environment which is dangerous to human health and disrupts the ecological balance. In this work, one nanocomposite immobilized zirconium (Zr, IV) was prepared and used as the affinity probes to quickly and selectively extract organophosphorus pesticides (OPPs) from water samples. The Fe3O4-ethylenediamine tetraacetic acid (EDTA)@Zr(IV) nanocomposites (NPs) were prepared by simply mixing Zr(IV) ions with Fe3O4-EDTA NPs synthesized by one-pot chemical co-precipitation method. The immobilized Zr(IV) ions were further utilized to capture OPPs based on their high affinity for the phosphate moiety in OPPs. Coupled with GC-MS, four OPPs were used as models to demonstrate the feasibility of this approach. Under the optimum conditions, the limits of detection for target OPPs were in the range of 0.10-10.30ngmL(-1) with relative standard deviations (RSDs) of 0.61-4.40% (n=3), respectively. The linear ranges were over three orders of magnitudes (correlation coefficients, R(2)>0.9995). The Fe3O4-EDTA@Zr(IV) NPs were successfully applied to extract OPPs samples with recoveries of 86.95-112.60% and RSDs of 1.20-10.42% (n=3) from two spiked real water. By the proposed method, the matrix interference could be effectively eliminated. We hope our finding can provide a promising alternative for the fast extraction of OPPs from complex real samples.

  20. THE STUDY OF CLINICAL FEATURES OF ORGANOPHOSPHORUS POISONING IN INDIAN SOCIETY

    Directory of Open Access Journals (Sweden)

    Anurag Srivastava

    2016-07-01

    Full Text Available RESEARCH QUESTION What are the clinical features of organophosphorus poisoning? DESIGN Prospective study; Interview technique. SAMPLE SIZE A total of 41 cases of OP poisoning were studied. Muscarinic, Nicotinic, and CNS symptoms according to duration and amount of poisoning are observed in observation. RESULT In this study, those patients who were admitted to our side with complaint of poisoning within 12 hours, muscarinic symptoms of organophosphate poisoning like miosis and pulmonary oedema were present in 100%, salivation was present in 85.7%, sweating was present in 71.4%, and nicotinic symptoms of organophosphate poisoning like neuromuscular paralysis was present in 4.7%. In those patients who were admitted with complaint of organophosphate poisoning more than 12 hours, nicotinic symptoms like fasciculations was present in 15% and neuromuscular paralysis was present in 20%. In CNS symptoms, tremors was present in 4.8% of patients admitted with complaint of poisoning within 12 hours and in 15% of patients admitted with complaints of poisoning more than 12 hours. In those patients who were admitted with complaint of poisoning of more than 5 grams of the substance, muscarinic symptoms like miosis was present in 85.7%, pulmonary oedema was present in 100%, salivation was present in 71.4%, and sweating was present in 42.9%. CNS symptoms like tremor was present in 14.3% of patients admitted with complaint of poisoning of more than 5 grams of the substance as compared to 0% in those who were admitted with complaint of poisoning of less than 5 grams of the substance suggesting that incidence of CNS symptoms (Tremor among poisoning patient was more in those patients who have taken more amount of organophosphate substance

  1. Evidence for nonacetylcholinesterase targets of organophosphorus nerve agent: supersensitivity of acetylcholinesterase knockout mouse to VX lethality.

    Science.gov (United States)

    Duysen, E G; Li, B; Xie, W; Schopfer, L M; Anderson, R S; Broomfield, C A; Lockridge, O

    2001-11-01

    The possibility that organophosphate toxicity is due to inhibition of targets other than acetylcholinesterase (AChE, EC 3.1.1.7) was examined in AChE knockout mice. Mice (34-55 days old) were grouped for this study, after it was determined that AChE, butyrylcholinesterase (BChE), and carboxylesterase activities had reached stable values by this age. Mice with 0, 50, or 100% AChE activity were treated subcutaneously with the nerve agent VX. The LD50 for VX was 10 to 12 microg/kg in AChE-/-, 17 microg/kg in AChE+/-, and 24 microg/kg in AChE+/+ mice. The same cholinergic signs of toxicity were present in AChE-/- mice as in wild-type mice, even though AChE-/- mice have no AChE whose inhibition could lead to cholinergic signs. Wild-type mice, but not AChE-/- mice, were protected by pretreatment with atropine. Tissues were extracted from VX-treated and untreated animals and tested for AChE, BChE, and acylpeptide hydrolase activity. VX treatment inhibited 50% of the AChE activity in brain and muscle of AChE+/+ and +/- mice, 50% of the BChE activity in all three AChE genotypes, but did not significantly inhibit acylpeptide hydrolase activity. It was concluded that the toxicity of VX must be attributed to inhibition of nonacetylcholinesterase targets in the AChE-/- mouse. Organophosphorus ester toxicity in wild-type mice is probably due to inhibition or binding to several proteins, only one of which is AChE.

  2. Repellent and insecticidal effects of the essential oil of Kaempferia galanga rhizomes to Liposcelis bostrychophila (Psocoptera: Liposcelidae).

    Science.gov (United States)

    Liu, Xin Chao; Liang, Yan; Shi, Wang Peng; Liu, Qi Zhi; Zhou, Ligang; Liu, Zhi Long

    2014-08-01

    The aim of this research was to determine chemical composition and repellent and insecticidal activities of the essential oil of Kaempferia galanga L. rhizomes against the booklouse, Liposcelis bostrychophila Badonnel, and to isolate insecticidal or repellent constituents from the oil. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. Twenty-eight components of the oil were identified. The major compounds in the oil were ethyl-rho-methoxycinnamate (38.6%), ethyl cinnamate (23.2%), 1,8-cineole (11.5%), trans-cinnamaldehyde (5.3%), and borneol (5.2%). Based on bioactivity-guided fractionation, four active constituents were isolated from the oil and identified as 1,8-cineole, ethyl cinnamate, ethyl rho-methoxycinnamate, and trans-cinnamaldehyde. The essential oil exhibited contact toxicity against the booklouse with an LC50 value of 68.6 microg/cm2. Ethyl cinnamate (LC50 = 21.4 microg/cm2) exhibited stronger contact toxicity than ethyl rho-methoxycinnamate and trans-cinnamaldehyde (LC50 = 44.6 and 43.4 microg/cm2, respectively) while 1,8-cineole showed weak acute toxicity. The essential oil also possessed fumigant toxicity against the booklouse with a LC50 value of 1.5 mg/liter air. 1,8-Cineole and trans-cinnamaldehyde (LC50 = 1.1 and 1.3 mg/liter, respectively) possessed stronger fumigant toxicity against the booklouse than ethyl cinnamate and ethyl rho-methoxycinnamate (LC50 = 10.2 and 10.2 mg/liter air, respectively). trans-Cinnamaldehyde was strongly repellent to booklice, whereas ethyl cinnamate and ethyl rho-methoxycinnamate were weakly repellent and 1,8-cineole did not repel booklice. The results indicate that the essential oil and its constituent compounds have potential for development into natural insecticides or fumigants and repellents for control of insects in stored grains.

  3. Synthesis of organophosphorus modified nanoparticles and their reinforcements on the fire safety and mechanical properties of polyurea

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Xiaodong [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Song, Lei, E-mail: leisong@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Wang, Bibo [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026 (China); USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Yuen, Richard K.K., E-mail: Richard.Yuen@cityu.edu.hk [USTC-CityU Joint Advanced Research Centre, Suzhou Key Laboratory of Urban Public Safety, Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren’ai Road Suzhou, Jiangsu 215123 (China); Department of Building and Construction, City University of Hong Kong, Tat Chee Avenue Kowloon (Hong Kong)

    2013-05-15

    Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized by the hydrolysis and condensation of both 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide modified vinyl trimethoxy silane (DOPO-VTS) and 3-triethoxysilylpropylamine. FRs-nanoparticles were incorporated into the polyurea matrix in different ratios via in situ polymerization, resulting in the formation of organic/inorganic nanocomposites. The nanocomposites were characterized by thermogravimetric analysis (TGA), real-time fourier transform infrared spectra (RTIR), microscale combustion calorimeter (MCC) and tensile testing machine. The TGA results revealed that FRs-nanoparticles could slightly catalyze the thermal degradation of the nanocomposites in nitrogen atmosphere, but significantly improve the thermal stability of the nanocomposites in air atmosphere. The T{sub 0.5} (50wt.% weight loss) of the nanocomposites was delayed by 32 °C in air atmosphere. Moreover, the char yield increased from 2.3wt.% to 8.9 wt.% at 550 °C when the loadings of FRs-nanoparticles was 10wt.%, indicating the catalyzing charring effect of FRs-nanoparticles. The MCC results revealed that all the nanocomposites exhibited much lower flammability compared with virgin polyurea. Furthermore, the tensile test indicated that the FRs-nanoparticles could also improve the mechanical properties of polyurea. - Highlights: ► Novel organophosphorus modified nanoparticles (FRs-nanoparticles) were synthesized. ► FRs-nanoparticles were incorporated into the polyurea. ► Both the thermal stability and mechanical properties of polyurea were improved.

  4. Novel restricted access materials combined to molecularly imprinted polymers for selective solid-phase extraction of organophosphorus pesticides from honey.

    Science.gov (United States)

    He, Juan; Song, Lixin; Chen, Si; Li, Yuanyuan; Wei, Hongliang; Zhao, Dongxin; Gu, Keren; Zhang, Shusheng

    2015-11-15

    A novel restricted access materials (RAM) combined to molecularly imprinted polymers (MIPs), using malathion as template molecule and glycidilmethacrylate (GMA) as pro-hydrophilic co-monomer, were prepared for the first time. RAM-MIPs with hydrophilic external layer were characterized by scanning electron microscopy and recognition and selectivity properties were compared with the restricted access materials-non-molecularly imprinted polymers (RAM-NIPs) and unmodified MIPs. RAM-MIPs were used as the adsorbent enclosed in solid phase extraction column and several important extraction parameters were comprehensively optimized to evaluate the extraction performance. Under the optimum extraction conditions, RAM-MIPs exhibited comparable or even higher selectivity with greater extraction capacity toward six kinds of organophosphorus pesticides (including malathion, ethoprophos, phorate, terbufos, dimethoate, and fenamiphos) compared with the MIPs and commercial solid phase extraction columns. The RAM-MIPs solid phase extraction coupled with gas chromatography was successfully applied to simultaneously determine six kinds of organophosphorus pesticides from honey sample. The new established method showed good linearity in the range of 0.01-1.0 μg mL(-1), low limits of detection (0.0005-0.0019 μg mL(-1)), acceptable reproducibility (RSD, 2.26-4.81%, n = 6), and satisfactory relative recoveries (90.9-97.6%). It was demonstrated that RAM-MIPs solid phase extraction with excellent selectivity and restricted access function was a simple, rapid, selective, and effective sample pretreatment method.

  5. Suitability of microwave-assisted extraction coupled with solid-phase extraction for organophosphorus pesticide determination in olive oil.

    Science.gov (United States)

    Fuentes, Edwar; Báez, María E; Quiñones, Adalí

    2008-10-17

    A systematic study of the microwave-assisted extraction coupled to solid-phase extraction of nine organophosphorus pesticides (dimethoate, diazinon, pirimiphos methyl, parathion methyl, malathion, fenthion, chlorpyriphos, methidathion and azinphos methyl) from olive oil is described. The method is based on microwave-assisted liquid-liquid extraction with partition of organophosphorus pesticides between an acetonitrile-dichloromethane mixture and oil. Cleanup of extracts was performed with ENVI-Carb solid-phase extraction cartridge using dichloromethane as the elution solvent. The determination of pesticides in the final extracts was carried out by gas chromatography-flame photometric detection and gas chromatography-tandem mass spectrometry, using a triple quadrupole mass analyzer, for confirmative purposes. The study and optimization of the method was achieved through experimental design where recovery of compounds using acetonitrile for partition ranged from 62 to 99%. By adding dichloromethane to the extracting solution, the recoveries of more hydrophobic compounds were significantly increased. Under optimized conditions recoveries of pesticides from oil were equal to or higher than 73%, except for fenthion and chlorpyriphos at concentrations higher than 0.06microgg(-1) and diazinon at 0.03microgg(-1), with RSDs equal to or lower than 11% and quantification limits ranging from 0.007 to 0.020microgg(-1). The proposed method was applied to residue determination of the selected pesticides in commercial olive and avocado oil produced in Chile.

  6. Organohalogen and organophosphorus pesticides in mixed feed rations: findings from FDA's domestic surveillance during fiscal years 1989-1994.

    Science.gov (United States)

    Lovell, R A; McChesney, D G; Price, W D

    1996-01-01

    During Fiscal Years 1989-1994, the U.S. Food and Drug Administration (FDA) collected and analyzed 545 domestic surveillance samples of mixed feed rations (172 for cattle, 125 for poultry, 83 for swine, 61 for pets, 56 for fish, and 48 miscellaneous). All samples were analyzed by gas-liquid chromatography for organohalogen and organophosphorus pesticides. Of the 545 samples, 88 (16.1%) did not contain detectable pesticide residues. In the 457 samples with detectable pesticide levels, 804 residues (654 quantitable and 150 trace) were found. None of these 804 residues exceeded regulatory guidance. Malathion, chlorpyrifos-methyl, diazinon, chlorpyrifos, and pirimiphos-methyl were the most commonly detected pesticides. These 5 organophosphorus pesticides accounted for 93.4% of all pesticide residues detected (malathion, 52.9%; chlorpyrifos-methyl, 25.2%; diazinon, 7.7%; chlorpyrifos, 4.9%; and pirimiphos-methyl, 2.7%). Their median values in samples containing quantitable levels ranged from 0.014 to 0.098 ppm. The most commonly detected organohalogen compounds were methoxychlor, DDE, PCB, dieldrin, pentachloronitrobenzene, and lindane. These 6 compounds combined accounted for only 4.1% of all residues detected. FDA is continuing its pesticide surveillance of feeds to help ensure animal safety and prevent violative residues in food derived from animals.

  7. Pharmacokinetics and effects on serum cholinesterase activities of organophosphorus pesticides acephate and chlorpyrifos in chimeric mice transplanted with human hepatocytes.

    Science.gov (United States)

    Suemizu, Hiroshi; Sota, Shigeto; Kuronuma, Miyuki; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-11-01

    Organophosphorus pesticides acephate and chlorpyrifos in foods have potential to impact human health. The aim of the current study was to investigate the pharmacokinetics of acephate and chlorpyrifos orally administered at lowest-observed-adverse-effect-level doses in chimeric mice transplanted with human hepatocytes. Absorbed acephate and its metabolite methamidophos were detected in serum from wild type mice and chimeric mice orally administered 150mg/kg. Approximately 70% inhibition of cholinesterase was evident in plasma of chimeric mice with humanized liver (which have higher serum cholinesterase activities than wild type mice) 1day after oral administrations of acephate. Adjusted animal biomonitoring equivalents from chimeric mice studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and in vitro metabolic clearance data with a simple physiologically based pharmacokinetic (PBPK) model. Estimated plasma concentrations of acephate and chlorpyrifos in humans were consistent with reported concentrations. Acephate cleared similarly in humans and chimeric mice but accidental/incidental overdose levels of chlorpyrifos cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in mice. The data presented here illustrate how chimeric mice transplanted with human hepatocytes in combination with a simple PBPK model can assist evaluations of toxicological potential of organophosphorus pesticides.

  8. Comparison of Two Procedures for Extraction and Clean-up of Organophosphorus and Pyrethroid Pesticides in Sediment

    Institute of Scientific and Technical Information of China (English)

    WANG Li-Gang; JIANG Xin; YAN Dong-Yun; S.FORSTER; D.MARTENS

    2004-01-01

    Two procedures were compared for extraction and clean-up of 20 organophosphorus and 19 pyrethroid pesticides in sediment to identify the more effective procedure for groups of pesticides or individual compounds. In Procedure Ⅰ,methanol/water and n-hexane were used for extraction,and 1:10 (v/v) dichloromethane in n-hexane and acetone were used as eluents for eluting the analyte through the cartridge,with one evaporating steps on a rotary evaporator and two eluting steps on the cartridge. n-hexane/acetone (2:1,v/v) was used for extraction and elution in Procedure Ⅱ with one evaporating step on a rotary evaporator and one eluting step on the cartridge. All extractions were performed under an ultrasonic bath and gas chromatography and mass spectrometry were utilized for measurements. Procedure Ⅱ was developed as a rapid,timesaving,less costly and safer substitute for Procedure Ⅰ which was an old method. Procedure Ⅱ was more effective for ahnost all the organophosphorus pesticides tested and 11 of the 19 pyrethroid pesticides,while Procedure Ⅰ was more appropriate for analysis of 5 pyrethroid pesticides. However,recoveries of most pyrethroid pesticides were fairly low. Thus,further studies should focus on adjustment and formulation of solvents for more efficient extraction and clean-up of pyrethroid pesticides from sediment samples.

  9. Acute Kidney Failure

    Science.gov (United States)

    ... out of balance. Acute kidney failure — also called acute renal failure or acute kidney injury — develops rapidly over ... 2015. Palevsky PM. Definition of acute kidney injury (acute renal failure). http://www.uptodate.com/home. Accessed April ...

  10. Acute Pancreatitis and Pregnancy

    Science.gov (United States)

    ... Pancreatitis Acute Pancreatitis and Pregnancy Acute Pancreatitis and Pregnancy Timothy Gardner, MD Acute pancreatitis is defined as ... pancreatitis in pregnancy. Reasons for Acute Pancreatitis and Pregnancy While acute pancreatitis is responsible for almost 1 ...

  11. Insecticide susceptibility in larval populations of the West Nile vector Culex pipiens L. (Diptera:Culicidae) in Saudi Arabia

    Institute of Scientific and Technical Information of China (English)

    Al Thabiani Aziz; Angelo Canale; Giovanni Benelli; Jazem Abdullah Mahyoub; Hasibur Rehman; Shalini Saggu; Kadarkarai Murugan; Chellasamy Panneerselvam; Majed Salum S Alrefaei; Marcello Nicoletti; Hui Wei

    2016-01-01

    Objective: To investigate the susceptibility to some conventional and non-conventional insecticides in laboratory and field larval populations of the West Nile vector Culex pipiens L. (Cx. pipiens), the dominant species in Jeddah Province, Saudi Arabia. Methods: The tested conventional insecticides were Actikil and Pesgard, while the non-conventional ones were Bacilod, Dudim and Baycidal. Probit analysis and photo-microscopical observations were carried out to shed light on acute toxicity in laboratory and field Cx. pipiens strains. Results: Cx. pipiens were more susceptible to Pesgard (LC50: 0.045 and 0.032 mg/L) than Actikil (0.052 and 0.038 mg/L) and Bacilod (0.129 and 0.104 mg/L), for the field and laboratory strains, respectively. Results showed that treatments with the chitin syn-thesis inhibitor Dudim and Baycidal evoked morphological effects similar to those induced by other insect growth regulators. According to IC50 values obtained (concen-tration which to inhibit the emergence of 50%of mosquito adults), the compound Dudim (0.000 3 and 0.000 1 mg/L) was more effective against Cx. pipiens L. mosquitoes than Baycidal (0.000 4 and 0.000 3 mg/L) for both the field and laboratory strains, respectively. Conclusions: Our results provide baseline data to enhance control programs and orient public health decisions on the selection of pesticides against mosquito vectors in Saudi Arabia.

  12. Insecticide susceptibility in larval populations of the West Nile vector Culex pipiens L.(Diptera: Culicidae) in Saudi Arabia

    Institute of Scientific and Technical Information of China (English)

    Al Thabiani Aziz; Jazem Abdullah Mahyoub; Hasibur Rehman; Shalini Saggu; Kadarkarai Murugan; Chellasamy Panneerselvam; Majed Salum S.Alrefaei; Marcello Nicoletti; Hui Wei; Angelo Canale; Giovanni Benelli

    2016-01-01

    Objective: To investigate the susceptibility to some conventional and non-conventional insecticides in laboratory and field larval populations of the West Nile vector Culex pipiens L.(Cx. pipiens), the dominant species in Jeddah Province, Saudi Arabia.Methods: The tested conventional insecticides were Actikil and Pesgard, while the nonconventional ones were Bacilod, Dudim and Baycidal. Probit analysis and photomicroscopical observations were carried out to shed light on acute toxicity in laboratory and field Cx. pipiens strains.Results: Cx. pipiens were more susceptible to Pesgard(LC50: 0.045 and 0.032 mg/L)than Actikil(0.052 and 0.038 mg/L) and Bacilod(0.129 and 0.104 mg/L), for the field and laboratory strains, respectively. Results showed that treatments with the chitin synthesis inhibitor Dudim and Baycidal evoked morphological effects similar to those induced by other insect growth regulators. According to IC50 values obtained(concentration which to inhibit the emergence of 50% of mosquito adults), the compound Dudim(0.000 3 and 0.000 1 mg/L) was more effective against Cx. pipiens L. mosquitoes than Baycidal(0.000 4 and 0.000 3 mg/L) for both the field and laboratory strains, respectively.Conclusions: Our results provide baseline data to enhance control programs and orient public health decisions on the selection of pesticides against mosquito vectors in Saudi Arabia.

  13. Metabolomic profiling of permethrin-treated Drosophila melanogaster identifies a role for tryptophan catabolism in insecticide survival.

    Science.gov (United States)

    Brinzer, Robert A; Henderson, Louise; Marchiondo, Alan A; Woods, Debra J; Davies, Shireen A; Dow, Julian A T

    2015-12-01

    Insecticides and associated synergists are rapidly losing efficacy in target insect pest populations making the discovery of alternatives a priority. To discover novel targets for permethrin synergists, metabolomics was performed on permethrin-treated Drosophila melanogaster. Changes were observed in several metabolic pathways including those for amino acids, glycogen, glycolysis, energy, nitrogen, NAD(+), purine, pyrimidine, lipids and carnitine. Markers for acidosis, ammonia stress, oxidative stress and detoxification responses were also observed. Many of these changes had not been previously characterized after permethrin exposure. From the altered pathways, tryptophan catabolism was selected for further investigation. The knockdown of some tryptophan catabolism genes (vermilion, cinnabar and CG6950) in the whole fly and in specific tissues including fat body, midgut and Malpighian tubules using targeted RNAi resulted in altered survival phenotypes against acute topical permethrin exposure. The knockdown of vermilion, cinnabar and CG6950 in the whole fly also altered survival phenotypes against chronic oral permethrin, fenvalerate, DDT, chlorpyriphos and hydramethylnon exposure. Thus tryptophan catabolism has a previously uncharacterized role in defence against insecticides, and shows that metabolomics is a powerful tool for target identification in pesticide research.

  14. Sub-chronic exposure to the insecticide dimethoate induces a proinflammatory status and enhances the neuroinflammatory response to bacterial lypopolysaccharide in the hippocampus and striatum of male mice.

    Science.gov (United States)

    Astiz, Mariana; Diz-Chaves, Yolanda; Garcia-Segura, Luis M

    2013-10-15

    Dimethoate is an organophosphorus insecticide extensively used in horticulture. Previous studies have shown that the administration of dimethoate to male rats, at a very low dose and during a sub-chronic period, increases the oxidation of lipids and proteins, reduces the levels of antioxidants and impairs mitochondrial function in various brain regions. In this study, we have assessed in C57Bl/6 adult male mice, whether sub-chronic (5weeks) intoxication with a low dose of dimethoate (1.4mg/kg) affects the expression of inflammatory molecules and the reactivity of microglia in the hippocampus and striatum under basal conditions and after an immune challenge caused by the systemic administration of lipopolysaccharide. Dimethoate increased mRNA levels of tumor necrosis factor α (TNFα) and interleukin (IL) 6 in the hippocampus, and increased the proportion of Iba1 immunoreactive cells with reactive phenotype in dentate gyrus and striatum. Lipopolysaccharide caused a significant increase in the mRNA levels of IL1β, TNFα, IL6 and interferon-γ-inducible protein 10, and a significant increase in the proportion of microglia with reactive phenotype in the hippocampus and the striatum. Some of the effects of lipopolysaccharide (proportion of Iba1 immunoreactive cells with reactive phenotype and IL6 mRNA levels) were amplified in the animals treated with dimethoate, but only in the striatum. These findings indicate that a sub-chronic period of administration of a low dose of dimethoate, comparable to the levels of the pesticide present as residues in food, causes a proinflammatory status in the brain and enhances the neuroinflammatory response to the lipopolysaccharide challenge with regional specificity.

  15. Sub-chronic exposure to the insecticide dimethoate induces a proinflammatory status and enhances the neuroinflammatory response to bacterial lypopolysaccharide in the hippocampus and striatum of male mice

    Energy Technology Data Exchange (ETDEWEB)

    Astiz, Mariana, E-mail: marianaastiz@gmail.com; Diz-Chaves, Yolanda, E-mail: ydiz@cajal.csic.es; Garcia-Segura, Luis M., E-mail: lmgs@cajal.csic.es

    2013-10-15

    Dimethoate is an organophosphorus insecticide extensively used in horticulture. Previous studies have shown that the administration of dimethoate to male rats, at a very low dose and during a sub-chronic period, increases the oxidation of lipids and proteins, reduces the levels of antioxidants and impairs mitochondrial function in various brain regions. In this study, we have assessed in C57Bl/6 adult male mice, whether sub-chronic (5 weeks) intoxication with a low dose of dimethoate (1.4 mg/kg) affects the expression of inflammatory molecules and the reactivity of microglia in the hippocampus and striatum under basal conditions and after an immune challenge caused by the systemic administration of lipopolysaccharide. Dimethoate increased mRNA levels of tumor necrosis factor α (TNFα) and interleukin (IL) 6 in the hippocampus, and increased the proportion of Iba1 immunoreactive cells with reactive phenotype in dentate gyrus and striatum. Lipopolysaccharide caused a significant increase in the mRNA levels of IL1β, TNFα, IL6 and interferon-γ-inducible protein 10, and a significant increase in the proportion of microglia with reactive phenotype in the hippocampus and the striatum. Some of the effects of lipopolysaccharide (proportion of Iba1 immunoreactive cells with reactive phenotype and IL6 mRNA levels) were amplified in the animals treated with dimethoate, but only in the striatum. These findings indicate that a sub-chronic period of administration of a low dose of dimethoate, comparable to the levels of the pesticide present as residues in food, causes a proinflammatory status in the brain and enhances the neuroinflammatory response to the lipopolysaccharide challenge with regional specificity. - Highlights: • The dose of pesticide used was comparable to the levels of residues found in food. • Dimethoate administration increased cytokine expression and microglia reactivity. • Hippocampus and striatum were differentially affected by the treatment.

  16. Natural products-based insecticidal agents 7. Semisynthesis and insecticidal activity of novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Xiao, Xiao; Wang, Qing-tian

    2010-09-01

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 16 novel 4alpha-alkyloxy-2-chloropodophyllotoxin derivatives were semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Among all the tested derivatives, especially compounds 4b, 4e, 4g, and 4p exhibited more promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach. Generally, it was obviously demonstrated that the length of straight-chain or branched-chain alkyloxy, and heteroatom-containing cycloalkyloxy at the C-4 position of 2-chloropodophyllotoxin were very important for the insecticidal activity.

  17. Natural products-based insecticidal agents 11. Synthesis and insecticidal activity of novel 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxin derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Zhang, Jun-Liang

    2011-09-15

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, 14 novel 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxin derivatives were stereoselectively semisynthesized from podophyllotoxin, and preliminarily evaluated for their insecticidal activity against the pre-third-instar larvae of Mythimna separata Walker in vivo. Especially compounds 9c' and 9g' exhibited the most promising and pronounced insecticidal activity than toosendanin, a commercial insecticide derived from Melia azedarach at 1mg/mL. Generally, it was preliminarily demonstrated that arylsulfonyloxy groups at the C-2 position of benzyloxy moiety and the length of the side chain on the benzenesulfonyloxy group of 4α-arylsulfonyloxybenzyloxy-2β-chloropodophyllotoxins might be important for the insecticidal activity.

  18. Natural-product-based insecticidal agents 14. Semisynthesis and insecticidal activity of new piperine-based hydrazone derivatives against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Qu, Huan; Yu, Xiang; Zhi, Xiaoyan; Lv, Min; Xu, Hui

    2013-10-15

    In continuation of our program aimed at the discovery and development of natural-product-based insecticidal agents, twenty-six new piperine-based hydrazone derivatives were synthesized from piperine, an alkaloid isolated from Piper nigrum Linn. The single-crystal structures of 6c, 6q and 6w were unambiguously confirmed by X-ray crystallography. Their insecticidal activity was evaluated against the pre-third-instar larvae of Mythimna separata Walker in vivo. Especially compounds 6b, 6i and 6r, the final mortality rates of which, at the concentration of 1 mg/mL, were 62.1%, 65.5% and 65.5%, respectively, exhibited more pronounced insecticidal activity compared to toosendanin at 1 mg/mL, a commercial botanical insecticide isolated from Melia azedarach. It suggested that introduction of the substituents at the C-2 position on the phenyl ring of the hydrazone derivatives was important for their insecticidal activity.

  19. Natural products-based insecticidal agents 9. Design, semisynthesis and insecticidal activity of 28-acyloxy derivatives of toosendanin against Mythimna separata Walker in vivo.

    Science.gov (United States)

    Xu, Hui; Zhang, Jun-Liang

    2011-04-01

    In continuation of our program aimed at the discovery and development of natural products-based insecticidal agents, twelve 28-acyloxy derivatives of toosendanin (2a-l) were semisynthesized and preliminarily evaluated their activity against the pre-third-instar larvae of Mythimna separata Walker in vivo at the concentration of 1mg/mL. Some compounds exhibited the potent insecticidal activity. Especially compounds 2c and 2j displayed the more promising insecticidal activity than their natural precursor, toosendanin, a commercial insecticide derived from Melia azedarach at 1mg/mL. In general, it indicated that the butanoyloxy or phenylacryloyloxy moiety at the 28-position of toosendanin was essential for the insecticidal activity.

  20. Resistance is not Futile: It Shapes Insecticide Discovery

    Directory of Open Access Journals (Sweden)

    Margaret C. Hardy

    2014-01-01

    Full Text Available Conventional chemical control compounds used for the management of insect pests have been much maligned, but still serve a critical role in protecting people and agricultural products from insect pests, as well as conserving biodiversity by eradicating invasive species. Although biological control can be an effective option for area-wide management of established pests, chemical control methods are important for use in integrated pest management (IPM programs, as well as in export treatments, eradicating recently arrived invasive species, and minimizing population explosions of vectors of human disease. Cogitated research and development programs have continued the innovation of insecticides, with a particular focus on combating insecticide resistance. Recent developments in the fields of human health, protecting the global food supply, and biosecurity will be highlighted.

  1. Synthesis and Insecticidal Activities of Novel Phthalic Acid Diamides

    Institute of Scientific and Technical Information of China (English)

    闫涛; 李玉新; 李永强; 王多义; 陈伟; 刘卓; 李正名

    2012-01-01

    In order to discover novel insecticides with the new action mode on ryanodine receptor (RyR), a series of novel phthalic acid diamide derivatives were designed and synthesized. All compounds were characterized by 1H NMR spectra and HRMS. The preliminary results of biological activity assessment indicated that some title compounds exhibited excellent insecticidal activities against Mythimna separata, Spodoptera exigua, and Plutella xylostella. The title compound 3-nitro-N-cyclopropyl-N'-[2-methyl-4-(perfluoropropan-2-yl)phenyl]phthalamidte (4a) was more efficient against diamondback moths than the control (chlorantraniliprole). The effects of some title compounds on intracellular calcium of neurons from the Spodoptera exigua proved that the title compounds were RyR activators.

  2. [INSECTICIDE RESISTANCE IN MAJOR MALARIA VECTORS IN UZBEKISTAN].

    Science.gov (United States)

    Zhakhongirov, Sh M; Saifiev, Sh T; Abidov, Z I

    2016-01-01

    The resistance of Anopheles artemievi to DDT (26.7%) and propoxur (80.0%) was established in the kishlak of Chubat, Bulungursky District, Samarkand Viloyati and that in the kishlak of Rastguzar, Uichinsky District, Namangan Viloyati, was 45.0 and 22.5%, respectively. In the kishlak of Navruz, Kanlikulsky District, Republic of Karakalpakstan, there was reduced propoxur susceptibil- ity (90.0% An. superpictus death); in other human settle- ments, An. artemievi was susceptible--100% death in the use of the test insecticides. An. superpictus proved to be susceptive to 7 test insecticides (other than propoxur). In Uzbekistan, the resistance of An. artemievi was noted only in a small area. Among the major malaria vectors, An. superpictus remained susceptible to pyrethroid insec- ticides.

  3. Secondary metabolites and insecticidal activity of Anemone pavonina.

    Science.gov (United States)

    Varitimidis, Christos; Petrakis, Panos V; Vagias, Constantinos; Roussis, Vassilios

    2006-01-01

    The insecticidal properties of the crude extracts of the leaves and flowers of Anemone pavonina were evaluated on Pheidole pallidula ants and showed significant levels of activity. Bioassay-guided fractionations led to the isolation of the butenolide ranunculin (1) as the active principle. Chemical investigations of the extracts showed them to contain as major components the sitosterol glycopyranoside lipids 2-5 and the glycerides 6-8. The structures of the metabolites were elucidated, following acetylation and hydrolysis of the natural products, by interpretation of their NMR and mass spectral data. The uncommon lipid metabolites 2-8 were isolated for the first time from the genus Anemone and this is the first report of insecticidal activity of the Anemone metabolite ranunculin against ants.

  4. Typical Monoterpenes as Insecticides and Repellents against Stored Grain Pests

    Directory of Open Access Journals (Sweden)

    Suelen L. Reis

    2016-02-01

    Full Text Available Five monoterpenes naturally occurring in essential oils were tested for their insecticidal and repellent activities against the bruchid beetle Callosobruchus maculatus and the maize weevil Sitophilus zeamais. The monoterpenes were highly efficient as inducers of mortality or repellency against both insect species. They were more efficient in their fumigant activity against C. maculatus than against S. zeamais, while this profile of action was inverted when considering the repellent activities. Eugenol was one the most effective fumigants against both insects and one the most effective repellent against C. maculatus, while citronellal and geranial were one the most effective repellents against S. zeamais. Functional and positional isomerism of the monoterpenes pairs appears to exert little or no influence on theirs effects, especially in case of repellency. The validation of the insecticidal/repellent efficacy of isolated monoterpenes may permit a more advantageous, rapid, economic and optimized approach to the identification of promising oils for commercial formulations when combined with ethnobotanical strategies.

  5. Fusion proteins containing insect-specific toxins as pest control agents: snowdrop lectin delivers fused insecticidal spider venom toxin to insect haemolymph following oral ingestion.

    Science.gov (United States)

    Fitches, Elaine; Edwards, Martin G; Mee, Christopher; Grishin, Eugene; Gatehouse, Angharad M R; Edwards, John P; Gatehouse, John A

    2004-01-01

    The mannose-specific snowdrop lectin (Galanthus nivalis agglutinin: GNA), when fed to insects, binds to the gut epithelium and passes into the haemolymph. The ability of GNA to act as a carrier protein to deliver an insecticidal spider venom neurotoxin (Segestria florentina toxin 1: SFI1) to the haemolymph of lepidopteran larvae was investigated. Constructs encoding SFI1 and an SFI1/GNA fusion protein were expressed in Pichia pastoris. The insecticidal activity of purified recombinant proteins on injection was found to be comparable to published values for SfI1 purified from spider venom [Toxicon 40 (2002) 125]. Whereas neither GNA nor SFI1 alone showed acute toxicity when fed to larvae of tomato moth (Lacanobia oleracea), feeding SFI1/GNA fusion at 2.5% of dietary proteins was insecticidal to first stadium larvae, causing 100% mortality after 6 days. The protein also showed a significant, dose dependent, toxicity towards fourth and fifth stadium larvae, with growth reduced by up to approximately 90% over a 4-day assay period compared to controls. Delivery of intact SFI1/GNA to the haemolymph in these insects was shown by western blotting; haemolymph samples from fusion-fed larvae contained a GNA-immunoreactive protein of the same molecular weight as the SFI1/GNA fusion. SFI1/GNA and similar fusion proteins offer a novel and effective approach for delivering haemolymph active toxins by oral administration, which could be used in crop protection by expression in transgenic plants.

  6. Susceptibility of Adult Mosquitoes to Insecticides in Aqueous Sucrose Baits

    Science.gov (United States)

    2011-06-01

    of the lack of ingestion as a result of repellency due to high survival of water-deprived control mosquitoes at 24 hr and the abundance of abdomens...Vol. 36, no. 1 Journal of Vector Ecology 59 Susceptibility of adult mosquitoes to insecticides in aqueous sucrose baits Sandra A. Allan Center for...2010 ABSTRACT: Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence and intermittently during their

  7. Evolution of Bacillus thuringiensis Cry toxins insecticidal activity

    OpenAIRE

    Bravo, Alejandra; Gómez, Isabel; Porta, Helena; García-Gómez, Blanca Ines; Rodriguez-Almazan, Claudia; Pardo, Liliana; Soberón, Mario

    2013-01-01

    Insecticidal Cry proteins produced by Bacillus thuringiensis are use worldwide in transgenic crops for efficient pest control. Among the family of Cry toxins, the three domain Cry family is the better characterized regarding their natural evolution leading to a large number of Cry proteins with similar structure, mode of action but different insect specificity. Also, this group is the better characterized regarding the study of their mode of action and the molecular basis of insect specificit...

  8. Insecticide residues cross-contamination of oilseeds during storage

    Directory of Open Access Journals (Sweden)

    Dauguet Sylvie

    2007-11-01

    Full Text Available Pesticide residues are found in oilseeds and crude oils: they are mainly organophosphate insecticides (pirimiphos-methyl, dichlorvos, malathion used in empty storage facilities and for application to stored cereal grains. Even if pests are found in stored oilseeds, French regulation does not permit use of these insecticides on stored oilseeds, as they have affinity for these lipophilic subtances. These residues arise from cross-contamination during mechanical contact with storage bins and grain handling equipment, and not from illegal use. This uptake of insecticide residues from their storage environment by oilseeds can lead to levels that exceed regulatory limits. An investigation of 11 grain storage companies allowed us to follow the course of 27 sunflower seeds batches, from reception at the storage facilities to outloading. Samples from each of these batches, made at outloading, were analysed content for insecticide residues. Traceability of sunflower seeds established by storers allowed us to identify the origine of observed cross-contamination cases. Substances discovered were dichlorvos, pirimiphos-methyl and malathion (and chlorpyriphos-methyl in a single case. Pirimiphos-methyl was most commonly detected, but most cases of non-accordance with regulatory levels were observed with dichlorvos and malathion. Main cross-contamination hazard resulted from treatment of cereals at outloading, just before sunflower seeds were outloaded, especially when these cereals treatments were frequent on that elevator. Other situations led to cross-contaminations, but generally of lower levels: outloading of sunflower seeds after outloading of cereal that was treated at the reception, several weeks or months before; sunflower seeds stored in bin that contained previously treated cereal; empty bins and handling equipment treated before receipt of sunflower seeds.

  9. Sucrose Improves Insecticide Activity Against Drosophila suzukii (Diptera: Drosophilidae).

    Science.gov (United States)

    Cowles, Richard S; Rodriguez-Saona, Cesar; Holdcraft, Robert; Loeb, Gregory M; Elsensohn, Johanna E; Hesler, Steven P

    2015-04-01

    The addition of sucrose to insecticides targeting spotted wing drosophila, Drosophila suzukii (Matsumura), enhanced lethality in laboratory, semifield, and field tests. In the laboratory, 0.1% sucrose added to a spray solution enhanced spotted wing drosophila feeding. Flies died 120 min earlier when exposed to spinosad residues at label rates enhanced with sucrose. Added sucrose reduced the LC50 for dried acetamiprid residues from 82 to 41 ppm in the spray solution. Laboratory bioassays of spotted wing drosophila mortality followed exposure to grape and blueberry foliage and/or fruit sprayed and aged in the field. On grape foliage, the addition of 2.4 g/liter of sugar with insecticide sprays resulted in an 11 and 6% increase of spotted wing drosophila mortality at 1 and 2 d exposures to residues, respectively, averaged over seven insecticides with three concentrations. In a separate experiment, spinetoram and cyantraniliprole reduced by 95-100% the larval infestation of blueberries, relative to the untreated control, 7 d after application at labeled rates when applied with 1.2 g/liter sucrose in a spray mixture, irrespective of rainfall; without sucrose infestation was reduced by 46-91%. Adding sugar to the organically acceptable spinosyn, Entrust, reduced larval infestation of strawberries by >50% relative to without sugar for five of the six sample dates during a season-long field trial. In a small-plot field test with blueberries, weekly applications in alternating sprays of sucrose plus reduced-risk insecticides, spinetoram or acetamiprid, reduced larval infestation relative to the untreated control by 76%; alternating bifenthrin and phosmet (without sucrose) reduced infestation by 65%.

  10. Insecticidal, Repellent and Fungicidal Properties of Novel Trifluoromethylphenyl Amides

    Science.gov (United States)

    2013-01-01

    Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amidesq Maia Tsikolia a,⇑, Ulrich R. Bernier a, Monique R. Coy a...Swale e, Jeffrey R. Bloomquist e aU.S. Department of Agriculture - Agricultural Research Service, Center for Medical, Agricultural , and Veterinary...dU.S. Department of Agriculture - Agricultural Research Service, Natural Products Utilization Research Unit, The University of Mississippi, University

  11. The impact of insecticides to local honey bee colony Apis cerana indica in laboratory condition

    Science.gov (United States)

    Putra, Ramadhani E.; Permana, Agus D.; Nuriyah, Syayidah

    2014-03-01

    Heavy use of insecticides considered as one of common practice at local farming systems. Even though many Indonesian researchers had stated the possible detrimental effect of insecticide on agriculture environment and biodiversity, researches on this subject had been neglected. Therefore, our purpose in this research is observing the impact of insecticides usage by farmer to non target organisme like local honey bee (Apis cerana indica), which commonly kept in area near agriculture system. This research consisted of field observations out at Ciburial, Dago Pakar, Bandung and laboratory tests at School of Life Sciences and Technology, Institut Teknologi Bandung. The field observations recorded visited agriculture corps and types of pollen carried by bees to the nest while laboratory test recorderd the effect of common insecticide to mortality and behavior of honey bees. Three types of insecticides used in this research were insecticides A with active agent Chlorantraniliprol 50 g/l, insecticide B with active agent Profenofos 500 g/l, and insecticides C with active agent Chlorantraniliprol 100 g/l and λ-cyhalotrin 50g/l. The results show that during one week visit, wild flower, Wedelia montana, visited by most honey bees with average visit 60 honey bees followed by corn, Zea mays, with 21 honey bees. The most pollen carried by foragers was Wedelia montana, Calliandra callothyrsus, and Zea mays. Preference test show that honeybees tend move to flowers without insecticides as the preference to insecticides A was 12.5%, insecticides B was 0%, and insecticides was C 4.2%. Mortality test showed that insecticides A has LD50 value 0.01 μg/μl, insecticide B 0.31 μg/μl, and insecticides C 0.09 μg/μl which much lower than suggested dosage recommended by insecticides producer. This research conclude that the use of insecticide could lower the pollination service provide by honey bee due to low visitation rate to flowers and mortality of foraging bees.

  12. Complexation of insecticide chlorantraniliprole with human serum albumin: Biophysical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Ding Fei [Department of Chemistry, China Agricultural University, No. 2 Yuanmingyuan Xi Road, Haidian District, Beijing 100193 (China); Liu Wei [College of Economics and Management, China Agricultural University, Beijing 100083 (China); Diao Jianxiong [Department of Chemistry, China Agricultural University, No. 2 Yuanmingyuan Xi Road, Haidian District, Beijing 100193 (China); Yin Bin [Key Laboratory of Pesticide Chemistry and Application Technology, Ministry of Agriculture, Department of Applied Chemistry, China Agricultural University, Beijing 100193 (China); Zhang Li, E-mail: zhli.work@gmail.co [Key Laboratory of Pesticide Chemistry and Application Technology, Ministry of Agriculture, Department of Applied Chemistry, China Agricultural University, Beijing 100193 (China); Sun Ying, E-mail: sunying@cau.edu.c [Department of Chemistry, China Agricultural University, No. 2 Yuanmingyuan Xi Road, Haidian District, Beijing 100193 (China)

    2011-07-15

    Chlorantraniliprole is a novel insecticide belonging to the diamide class of selective ryanodine receptor agonists. A biophysical study on the binding interaction of a novel diamide insecticide, chlorantraniliprole, with staple in vivo transporter, human serum albumin (HSA) has been investigated utilizing a combination of steady-state and time-resolved fluorescence, circular dichroism (CD), and molecular modeling methods. The interaction of chlorantraniliprole with HSA gives rise to fluorescence quenching through static mechanism, this corroborates the fluorescence lifetime outcomes that the ground state complex formation and the predominant forces in the HSA-chlorantraniliprole conjugate are van der Waals forces and hydrogen bonds, as derived from thermodynamic analysis. The definite binding site of chlorantraniliprole in HSA has been identified from the denaturation of protein, competitive ligand binding, and molecular modeling, subdomain IIIA (Sudlow's site II) was designated to possess high-affinity binding site for chlorantraniliprole. Moreover, using synchronous fluorescence, CD, and three-dimensional fluorescence we testified some degree of HSA structure unfolding upon chlorantraniliprole binding. - Highlights: {yields} Our study highlights for the first time how binding dynamics can predominate for the new diamide insecticide, chlorantraniliprole. {yields} Chlorantraniliprole is situated within subdomain IIIA, Sudlow's site II, which is the same as that of indole-benzodiazepine site. {yields} Biophysical and molecular modeling approaches are useful to resolve the ligand interaction with biomacromolecule. {yields} It serves as a protective device in binding and in inactivating potential toxic compounds to which the body is exposed.

  13. Photodegradation of neonicotinoid insecticides in water by semiconductor oxides.

    Science.gov (United States)

    Fenoll, José; Garrido, Isabel; Hellín, Pilar; Flores, Pilar; Navarro, Simón

    2015-10-01

    The photocatalytic degradation of three neonicotinoid insecticides (NIs), thiamethoxam (TH), imidacloprid (IM) and acetamiprid (AC), in pure water has been studied using zinc oxide (ZnO) and titanium dioxide (TiO2) as photocatalysts under natural sunlight and artificial light irradiation. Photocatalytic experiments showed that the addition of these chalcogenide oxides in tandem with the electron acceptor (Na2S2O8) strongly enhances the degradation rate of these compounds in comparison with those carried out with ZnO and TiO2 alone and photolytic tests. Comparison of catalysts showed that ZnO is the most efficient for the removal of such insecticides in optimal conditions and at constant volumetric rate of photon absorption. Thus, the complete disappearance of all the studied compounds was achieved after 10 and 30 min of artificial light irradiation, in the ZnO/Na2S2O8 and TiO2/Na2S2O8 systems, respectively. The highest degradation rate was noticed for IM, while the lowest rate constant was obtained for AC under artificial light irradiation. In addition, solar irradiation was more efficient compared to artificial light for the removal of these insecticides from water. The main photocatalytic intermediates detected during the degradation of NIs were identified.

  14. Neonicotinoid insecticides can serve as inadvertent insect contraceptives

    Science.gov (United States)

    Villamar-Bouza, Laura; Bruckner, Selina; Chantawannakul, Panuwan; Gauthier, Laurent; Khongphinitbunjong, Kitiphong; Retschnig, Gina; Troxler, Aline; Vidondo, Beatriz; Neumann, Peter; Williams, Geoffrey R.

    2016-01-01

    There is clear evidence for sublethal effects of neonicotinoid insecticides on non-target ecosystem service-providing insects. However, their possible impact on male insect reproduction is currently unknown, despite the key role of sex. Here, we show that two neonicotinoids (4.5 ppb thiamethoxam and 1.5 ppb clothianidin) significantly reduce the reproductive capacity of male honeybees (drones), Apis mellifera. Drones were obtained from colonies exposed to the neonicotinoid insecticides or controls, and subsequently maintained in laboratory cages until they reached sexual maturity. While no significant effects were observed for male teneral (newly emerged adult) body mass and sperm quantity, the data clearly showed reduced drone lifespan, as well as reduced sperm viability (percentage living versus dead) and living sperm quantity by 39%. Our results demonstrate for the first time that neonicotinoid insecticides can negatively affect male insect reproductive capacity, and provide a possible mechanistic explanation for managed honeybee queen failure and wild insect pollinator decline. The widespread prophylactic use of neonicotinoids may have previously overlooked inadvertent contraceptive effects on non-target insects, thereby limiting conservation efforts. PMID:27466446

  15. Neonicotinoid insecticides can serve as inadvertent insect contraceptives.

    Science.gov (United States)

    Straub, Lars; Villamar-Bouza, Laura; Bruckner, Selina; Chantawannakul, Panuwan; Gauthier, Laurent; Khongphinitbunjong, Kitiphong; Retschnig, Gina; Troxler, Aline; Vidondo, Beatriz; Neumann, Peter; Williams, Geoffrey R

    2016-07-27

    There is clear evidence for sublethal effects of neonicotinoid insecticides on non-target ecosystem service-providing insects. However, their possible impact on male insect reproduction is currently unknown, despite the key role of sex. Here, we show that two neonicotinoids (4.5 ppb thiamethoxam and 1.5 ppb clothianidin) significantly reduce the reproductive capacity of male honeybees (drones), Apis mellifera Drones were obtained from colonies exposed to the neonicotinoid insecticides or controls, and subsequently maintained in laboratory cages until they reached sexual maturity. While no significant effects were observed for male teneral (newly emerged adult) body mass and sperm quantity, the data clearly showed reduced drone lifespan, as well as reduced sperm viability (percentage living versus dead) and living sperm quantity by 39%. Our results demonstrate for the first time that neonicotinoid insecticides can negatively affect male insect reproductive capacity, and provide a possible mechanistic explanation for managed honeybee queen failure and wild insect pollinator decline. The widespread prophylactic use of neonicotinoids may have previously overlooked inadvertent contraceptive effects on non-target insects, thereby limiting conservation efforts.

  16. Bacterial Vegetative Insecticidal Proteins (Vip) from Entomopathogenic Bacteria.

    Science.gov (United States)

    Chakroun, Maissa; Banyuls, Núria; Bel, Yolanda; Escriche, Baltasar; Ferré, Juan

    2016-06-01

    Entomopathogenic bacteria produce insecticidal proteins that accumulate in inclusion bodies or parasporal crystals (such as the Cry and Cyt proteins) as well as insecticidal proteins that are secreted into the culture medium. Among the latter are the Vip proteins, which are divided into four families according to their amino acid identity. The Vip1 and Vip2 proteins act as binary toxins and are toxic to some members of the Coleoptera and Hemiptera. The Vip1 component is thought to bind to receptors in the membrane of the insect midgut, and the Vip2 component enters the cell, where it displays its ADP-ribosyltransferase activity against actin, preventing microfilament formation. Vip3 has no sequence similarity to Vip1 or Vip2 and is toxic to a wide variety of members of the Lepidoptera. Its mode of action has been shown to resemble that of the Cry proteins in terms of proteolytic activation, binding to the midgut epithelial membrane, and pore formation, although Vip3A proteins do not share binding sites with Cry proteins. The latter property makes them good candidates to be combined with Cry proteins in transgenic plants (Bacillus thuringiensis-treated crops [Bt crops]) to prevent or delay insect resistance and to broaden the insecticidal spectrum. There are commercially grown varieties of Bt cotton and Bt maize that express the Vip3Aa protein in combination with Cry proteins. For the most recently reported Vip4 family, no target insects have been found yet.

  17. CLINICAL STUDY OF ACUTE POISONING: A RETROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Praveen

    2014-11-01

    Full Text Available : OBJECTIVES: To determine the common agents, clinical features and outcomes of acute poisoning. MATERIALS AND METHODS: A retrospective study of patients of acute poisoning of more than 14 years age admitted through emergency with a history of intentional, self-inflicted and suicidal poisoning in SRMS-IMS from Jan 2010 to Dec 2012. RESULTS: A total of 58 cases were included with a common age of affection 16 to 25 years and male to female ratio 1.63: 1. Poisoning cases occur throughout the year with maximum prevalence in May and minimum in June. Organophosphorus was the most common poison followed by aluminium phosphide. Vomiting was the most common symptoms followed by altered sensorium. 70.68% patients were discharged, 20.68% expired and 8.62% left against medical advice. Aluminium phosphide was the most common toxin consumed by dead patients. CONCLUSION: Acute poisoning is commonly affecting young population and is caused by variety of toxin. High mortality is associated with aluminum phosphide.

  18. Effects of neem-based insecticides on beet armyworm (Lepidoptera: Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    SHOILM.GREENBERG; ALLANT.SHOWLER; TONG-XIANLIU

    2005-01-01

    Three commercial neem [Azadirachta indica A. Juss (Meliaceae)]-based insecticides, Agroneem, Ecozin, and Neemix, and a non-commercial neem leaf powder,were evaluated for oviposition deterrence, antifeedant effect on larvae, and toxicity to eggs and larvae of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae),on cotton leaves in the laboratory. Oviposition deterrence in no-choice, and two- and fivechoice assays, was observed for the neem-based insecticide treatments when compared with a non-treated control. Neem-based insecticides also deterred feeding by beet armyworm larvae. Direct contact with neem-based insecticides decreased the survival of beet armyworm eggs. Survival of beet armyworm larvae fed for 7 days on leaves treated with neembased insecticides was reduced to 27, 33, 60, and 61% for neem leaf powder, Ecozin,Agroneem, and Neemix, respectively. Possibilities for adoption of neem-based insecticides in commercial cotton for beet armyworm control are discussed.

  19. Impaired brain StAR and HSP70 gene expression in zebrafish exposed to Methyl-Parathion based insecticide.

    Science.gov (United States)

    da Rosa, João Gabriel Santos; Koakoski, Gessi; Piato, Angelo L; Bogo, Maurício Reis; Bonan, Carla Denise; Barcellos, Leonardo José Gil

    2016-01-01

    Fish production ponds and natural water body areas located in close proximity to agricultural fields receive water with variable amounts of agrochemicals, and consequently, compounds that produce adverse effects may reach nontarget organisms. The aim of this study was to investigate whether waterborne methyl-parathion-based insecticide (MPBI) affected gene expression patterns of brain glucocorticoid receptor (GR), steroidogenic acute regulatory protein (StAR), and heat shock protein 70 (hsp70) in adult zebrafish (Danio rerio) exposed to this chemical for 96 h. Treated fish exposed to MPBI-contaminated water showed an inhibition of brain StAR and hsp70 gene expression. Data demonstrated that MPBI produced a decrease brain StAR and hsp70 gene expression.

  20. Tracing organophosphorus and brominated flame retardants and plasticizers in an estuarine food web.

    Science.gov (United States)

    Brandsma, Sicco H; Leonards, Pim E G; Leslie, Heather A; de Boer, Jacob

    2015-02-01

    Nine organophosphorus flame retardants (PFRs) were detected in a pelagic and benthic food web of the Western Scheldt estuary, The Netherlands. Concentrations of several PFRs were an order of magnitude higher than those of the brominated flame retardants (BFRs). However, the detection frequency of the PFRs (6-56%) was lower than that of the BFRs (50-97%). Tris(2-butoxyethyl) phosphate (TBOEP), tris(isobutyl) phosphate (TIBP) and tris(2-chloroisopropyl) phosphate (TCIPP) were the dominant PFRs in sediment with median concentrations of 7.0, 8.1 and 1.8 ng/g dry weight (dw), respectively. PFR levels in the suspended particular matter (SPM) were 2-12 times higher than that in sediment. TBOEP, TCIPP, TIBP, tris(2-chloroethyl) phosphate (TCEP) and tris(phenyl) phosphate (TPHP) were found in organisms higher in the estuarine food web. The highest PFR concentrations in the benthic food web were found in sculpin, goby and lugworm with median concentrations of 17, 7.4, 4.6 and 2.0 ng/g wet weight (ww) for TBOEP, TIBP, TCIPP and TPHP, respectively. Comparable levels were observed in the pelagic food web, BDE209 was the predominant PBDE in sediment and SPM with median concentrations up to 9.7 and 385 ng/g dw, respectively. BDE47 was predominant in the biotic compartment of the food web with highest median levels observed in sculpin and common tern eggs of 79 ng/g lipid weight (lw) (2.5 ng/g ww) and 80 ng/g lw (11 ng/g ww), respectively. Trophic magnification was observed for all PBDEs with the exception of BDE209. Indications of trophic magnification of PFRs were observed in the benthic food web for TBOEP, TCIPP and TCEP with tentative trophic magnification factors of 3.5, 2.2 and 2.6, respectively (pwebs. The relative high PFR levels in several fish species suggest high emissions and substantial exposure of organisms to PFRs in the Western Scheldt.

  1. Human hepatic cytochrome P450-specific metabolism of the organophosphorus pesticides methyl parathion and diazinon.

    Science.gov (United States)

    Ellison, Corie A; Tian, Yuan; Knaak, James B; Kostyniak, Paul J; Olson, James R

    2012-01-01

    Organophosphorus pesticides (OPs) are a public health concern due to their worldwide use and documented human exposures. Phosphorothioate OPs are metabolized by cytochrome P450s (P450s) through either a dearylation reaction to form an inactive metabolite, or through a desulfuration reaction to form an active oxon metabolite, which is a potent cholinesterase inhibitor. This study investigated the rate of desulfuration (activation) and dearylation (detoxification) of methyl parathion and diazinon in human liver microsomes. In addition, recombinant human P450s were used to determine the P450-specific kinetic parameters (K(m) and V(max)) for each compound for future use in refining human physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models of OP exposure. The primary enzymes involved in bioactivation of methyl parathion were CYP2B6 (K(m) = 1.25 μM; V(max) = 9.78 nmol · min(-1) · nmol P450(-1)), CYP2C19 (K(m) = 1.03 μM; V(max) = 4.67 nmol · min(-1) · nmol P450(-1)), and CYP1A2 (K(m) = 1.96 μM; V(max) = 5.14 nmol · min(-1) · nmol P450(-1)), and the bioactivation of diazinon was mediated primarily by CYP1A1 (K(m) = 3.05 μM; V(max) = 2.35 nmol · min(-1) · nmol P450(-1)), CYP2C19 (K(m) = 7.74 μM; V(max) = 4.14 nmol · min(-1) · nmol P450(-1)), and CYP2B6 (K(m) = 14.83 μM; V(max) = 5.44 nmol · min(-1) · nmol P450(-1)). P450-mediated detoxification of methyl parathion only occurred to a limited extent with CYP1A2 (K(m) = 16.8 μM; V(max) = 1.38 nmol · min(-1) · nmol P450(-1)) and 3A4 (K(m) = 104 μM; V(max) = 5.15 nmol · min(-1) · nmol P450(-1)), whereas the major enzyme involved in diazinon detoxification was CYP2C19 (K(m) = 5.04 μM; V(max) = 5.58 nmol · min(-1) · nmol P450(-1)). The OP- and P450-specific kinetic values will be helpful for future use in refining human PBPK/PD models of OP exposure.

  2. Dose-response effects of atropine and HI-6 treatment of organophosphorus poisoning in guinea pigs.

    Science.gov (United States)

    Koplovitz, I; Menton, R; Matthews, C; Shutz, M; Nalls, C; Kelly, S

    1995-01-01

    HI-6 (1-2-hydroxyiminomethyl-1-pyridino-3-(4-carbamoyl-1-pyridino -2- oxapropane dichloride) has been evaluated as an oxime alternative to pralidoxime, and toxogonin in the treatment of organophosphorus (OP) poisoning. The dose response effects of atropine (ATR) and HI-6 were investigated to more fully explore the interaction of these compounds in the treatment of OP poisoning. ATR, HI-6 and various combinations of the two drugs were evaluated against lethal poisoning by soman (GD) and tabun (GA) in guinea pigs. The effect of adjunctive diazepam treatment on the efficacy of atropine and HI-6 against soman was also investigated. Animals of either sex were challenged s.c. with OP and treated i.m. 1 min later with ATR and/or HI-6. When used, diazepam was injected immediately after ATR+HI6. LD50s of each treatment were calculated from probit models based on 24-hour survival against 5 levels of nerve agent and 6 animals per challenge level. A protective index (PI) was calculated by dividing the nerve agent LD50 in the presence of treatment by the LD50 in the absence of treatment. Treatment with HI6 alone had little effect on the toxicity of either OP. Treatment with ATR alone was more effective than HI-6 alone and was significantly more effective against soman than against tabun. When used in combination atropine and HI-6 had a strong synergistic effect against both agents. The dose of atropine used with HI-6 was critical in determining the efficacy of HI-6 against either agent. The slopes of the dose-lethality curves were minimally affected by the dose of ATR or HI-6. Adjunctive treatment with diazepam enhanced the efficacy of HI-6 and atropine against soman. It is concluded that 1) ATR has a large effect on the efficacy of HI-6 against OP poisoning, 2) the dose of ATR must be carefully selected in studies investigating the efficacy of HI-6 against OP poisoning, 3) the effective dose of ATR in the guinea pig is approximately 16 mg/kg, and 4) diazepam is a useful

  3. Prediction of insecticidal activity of Bacillus thuringiensis strains by polymerase chain reaction product profiles.

    OpenAIRE

    Carozzi, N B; Kramer, V C; Warren, G W; Evola, S; Koziel, M G

    1991-01-01

    A rapid analysis of Bacillus thuringiensis strains predictive of insecticidal activity was established by using polymerase chain reaction (PCR) technology. Primers specific to regions of high homology within genes encoding three major classes of B. thuringiensis crystal proteins were used to generate a PCR product profile characteristic of each insecticidal class. Predictions of insecticidal activity were made on the basis of the electrophoretic patterns of the PCR products. Included in the s...

  4. A Standardized Lepidopteran Bioassay to Investigate the Bioactivity of Insecticidal Proteins Produced in Transgenic Crops.

    Science.gov (United States)

    Graser, Gerson; Walters, Frederick S

    2016-01-01

    Insecticidal bioassays are the only reliable method to investigate the biological activity of an insecticidal protein and therefore provide an essential toolkit for the characterization and potency determination of these proteins. Here we present a standardized method for a lepidopteran larval bioassay, which is optimized to specifically estimate activity of insecticidal proteins produced in transgenic plants. The treatment can be either applied to the surface of the artificial diet, or blended into the diet.

  5. Additive effects on the improvement of insecticidal activity: Design, synthesis, and insecticidal activity of novel pymetrozine derivatives.

    Science.gov (United States)

    Yang, Yan; Liu, Yuxiu; Song, Hongjian; Li, Yongqiang; Wang, Qingmin

    2016-02-01

    A series of new pymetrozine analogues containing both methyl on the imine carbon and phenoxy group at the pyridine ring were designed and synthesized. Their insecticidal activities against bean aphid (Aphis craccivora), mosquito larvae (Culex pipiens pallens), cotton bollworm (Helicoverpa armigera), corn borer (Ostrinia nubilalis) and oriental armyworm (Mythimna separata) were evaluated. The results of bioassays indicated that most of the target compounds showed good insecticidal activity against bean aphid; especially, IIIf (80%) and IIIl (80%) exhibited higher aphicidal activity than pymetrozine (30%) at 5mg/kg, and the two compounds still showed 20% and 30% mortality at 2.5mg/kg, respectively, whereas pymetrozine displayed no activity at the same concentration. These compounds exhibited a completely different structure-activity relationship to that of known pymetrozine derivatives, in which it is thought introducing alkyl group on the imine carbon could be detrimental to the activities. Our new result suggested that the methyl on the imine carbon and phenoxy group at the pyridine ring of phenoxy group may play additive effects on the improvement of aphicidal activity. Besides this, compound IIIs, containing an allyl at the para position of phenoxy group, exhibited excellent insecticidal activity against mosquito larvae, lepidoptera pests cotton bollworm, corn borer and oriental armyworm.

  6. Impact and Selectivity of Insecticides to Predators and Parasitoids

    Directory of Open Access Journals (Sweden)

    Flávio Lemes Fernandes

    2010-04-01

    Full Text Available Problems with the use of insecticides has brought losses, such as, negative impact on natural enemies. When these beneficial insects reduce cause the eruption of pests and resurgence it’s more common. Thus principles of conservation these arthropods are extremely important in the biological natural control of pests, so that these enemies may present a high performance. Because of the negative impacts caused by insecticides on agriculture and their harmful effects on natural enemies, the objective of this article is to approach two important subjects, divided into three parts. Part I relates to the description of the main crop pests and their natural enemies; Part II involves the impact of insecticides on predators and parasitoids and Part III focuses on the selectivity of several groups of insecticides to natural enemies. Before spraying insecticides, it is necessary to choose a product that is efficient to pests and selective to natural enemies. So, it is indispensable to identify correctly the groups and species of natural enemies, since insecticides have an impact on their survival, growth, development, reproduction (sexual ratio, fecundity, longevity and fertility, and behavior (motility, orientation, feeding, oviposition and learning of insects. The mechanisms of toxicity and selectivity of insecticides are related to the properties of higher or lower solubility and molecular weight. Besides, characteristics of the cuticular composition of the integument of natural enemies are extremely important in the selectivity of a product or the tolerance of a certain predator or parasitoid to this molecules.Impacto e Seletividade de Inseticidas para Predadores e ParasitóidesResumo.Dentre os problemas advindos do uso de inseticidas, a destruição de inimigos naturais é fator importante. Estes insetos benéficos podem reduzir problemas de erupção de pragas secundárias, ressurgência de pragas e manter a praga abaixo do nível de dano econ

  7. Indirect evidence that agricultural pesticides select for insecticide resistance in the malaria vector Anopheles gambiae.

    Science.gov (United States)

    Luc, Djogbénou S; Benoit, Assogba; Laurette, Djossou; Michel, Makoutode

    2016-06-01

    We investigated the possible relationship between the agricultural use of insecticides and the emergence of insecticide resistance. Bioassays were conducted using simulated mosquito larval habitats and well known Anopheles gambiae strains. Soil samples were collected from vegetable production areas in Benin, including one site with insecticide use, one site where insecticides had not been used for two months, and a third where insecticides had not been used. Pupation and emergence rates were very low in pyrethroid-susceptible strains when exposed to soil that had been recently exposed to insecticides. Pupation and emergence rates in strains with the kdr mutation alone or both the kdr and Ace-1 mutations were much higher. Overall, strains with the kdr mutation survived at higher rates compared to that without kdr mutation. Although this study is observational, we provide indirect evidence indicating that soils from agricultural areas contain insecticide residues that can play a role in the emergence of insecticide resistance in Anopheles. This aspect should be taken into account to better utilize the insecticide in the context of integrated pest management programs.

  8. Moving From the Old to the New: Insecticide Research on Bed Bugs since the Resurgence

    Directory of Open Access Journals (Sweden)

    Alvaro Romero

    2011-05-01

    Full Text Available The scarcity of bed bugs in many countries over the last 50 years has resulted in a lack of modern research into the toxicology of this pest. Although bed bugs resurged in the late 1990s, published research related to insecticides has lagged behind and only began to appear in 2006. The difficulty in controlling bed bugs triggered the interest of both private and academic sectors to determine the value of currently available insecticides. What follows, is updated information on effectiveness of products, studies on insecticide susceptibility, identification of mechanisms of insecticide resistance and chemical strategies proposed to overcome resistance in modern bed bug populations.

  9. Posttreatment Feeding Affects Mortality of Bed Bugs (Hemiptera: Cimicidae) Exposed to Insecticides.

    Science.gov (United States)

    Singh, Narinderpal; Wang, Changlu; Cooper, Richard

    2016-02-01

    Insecticide sprays and dusts are used for controlling bed bugs, Cimex lectularius L. In natural environments, bed bugs have daily access to hosts after they are exposed to insecticides. The established laboratory insecticide bioassay protocols do not provide feeding after insecticide treatments, which can result in inflated mortality compared with what would be encountered in the field. We evaluated the effect of posttreatment feeding on mortality of bed bugs treated with different insecticides. None of the insecticides tested had a significant effect on the amount of blood consumed and percent feeding. The effect of posttreatment feeding on bed bug mortality varied among different insecticides. Feeding significantly reduced mortality in bed bugs exposed to deltamethrin spray, an essential oil mixture (Bed Bug Fix) spray, and diatomaceous earth dust. Feeding increased the mean survival time for bed bugs treated with chlorfenapyr spray and a spray containing an essential oil mixture (Ecoraider), but did not affect the final mortality. First instars hatched from eggs treated with chlorfenapyr liquid spray had reduced feeding compared with nymphs hatched from nontreated eggs. Those nymphs hatched from eggs treated with chlorfenapyr liquid spray and successfully fed had reduced mortality and a higher mean survival time than those without feeding. We conclude that the availability of a bloodmeal after insecticide exposure has a significant effect on bed bug mortality. Protocols for insecticide efficacy testing should consider offering a bloodmeal to the treated bed bugs within 1 to 3 d after treatment.

  10. Effects of persistent insecticides on beneficial soil arthropod in conventional fields compared to organic fields, puducherry.

    Science.gov (United States)

    Anbarashan, Padmavathy; Gopalswamy, Poyyamoli

    2013-07-15

    The usage of synthetic fertilizers/insecticides in conventional farming has dramatically increased over the past decades. The aim of the study was to compare the effects of bio-pesticides and insecticides/pesticides on selected beneficial non targeted arthropods. Orders Collembola, Arachinida/Opiliones, Oribatida and Coleoptera were the main groups of arthropods found in the organic fields and Coleoptera, Oribatida, Gamasida and Collembola in conventional fields. Pesticides/insecticides had a significant effect on non-targeted arthropods order- Collembola, Arachinida/Opiliones, Hymenoptera and Thysonoptera were suppressed after pesticides/insecticides spraying. Bio-insecticides in organic fields had a non-significant effect on non targeted species and they started to increase in abundance after 7 days of spraying, whereas insecticide treatment in conventional fields had a significant long-term effect on non targeted arthropods and short term effect on pests/insects, it started to increase after 21 days of the spraying. These results indicate that insecticide treatment kept non targeted arthropods at low abundance. In conclusion, organic farming does not significantly affected the beneficial-non targeted arthropods biodiversity, whereas preventive insecticide application in conventional fields had significant negative effects on beneficial non targeted arthropods. Therefore, conventional farmers should restrict insecticide applications, unless pest densities reach the thresholds and more desirably can switch to organic farming practices.

  11. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-02-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  12. Delayed action insecticides and their role in mosquito and malaria control.

    Science.gov (United States)

    Wang, Chuncheng; Gourley, Stephen A; Liu, Rongsong

    2014-01-01

    There is considerable interest in the management of insecticide resistance in mosquitoes. One possible approach to slowing down the evolution of resistance is to use late-life-acting (LLA) insecticides that selectively kill only the old mosquitoes that transmit malaria, thereby reducing selection pressure favoring resistance. In this paper we consider an age-structured compartmental model for malaria with two mosquito strains that differ in resistance to insecticide, using an SEI approach to model malaria in the mosquitoes and thereby incorporating the parasite developmental times for the two strains. The human population is modeled using an SEI approach. We consider both conventional insecticides that target all adult mosquitoes, and LLA insecticides that target only old mosquitoes. According to linearised theory the potency of the insecticide affects mainly the speed of evolution of resistance. Mutations that confer resistance can also affect other parameters such as mean adult life span and parasite developmental time. For both conventional and LLA insecticides the stability of the malaria-free equilibrium, with only the resistant mosquito strain present, depends mainly on these other parameters. This suggests that the main long term role of an insecticide could be to induce genetic changes that have a desirable effect on a vital parameter such as adult life span. However, when this equilibrium is unstable, numerical simulations suggest that a potent LLA insecticide can slow down the spread of malaria in humans but that the timing of its action is very important.

  13. Effects of irrigation levels on interactions among Lygus hesperus (Hemiptera: Miridae), insecticides, and predators in cotton.

    Science.gov (United States)

    Asiimwe, Peter; Naranjo, Steven E; Ellsworth, Peter C

    2014-04-01

    Variation in plant quality and natural enemy abundance plays an important role in insect population dynamics. In manipulative field studies, we evaluated the impact of varying irrigation levels and insecticide type on densities of Lygus hesperus Knight and the arthropod predator community in cotton. Three watering levels were established via irrigations timed according to three levels of percent soil water depletion (SWD): 20, 40, or 60, where 40% SWD is considered standard grower practice, 60% represents a deficit condition likely to impose plant productivity losses, and 20% represents surplus conditions with likely consequences on excessive vegetative plant production. The two key L. hesperus insecticides used were the broad-spectrum insecticide acephate and the selective insecticide flonicamid, along with an untreated check. We hypothesized that densities of L. hesperus and its associated predators would be elevated at higher irrigation levels and that insecticides would differentially impact L. hesperus and predator dynamics depending on their selectivity. L. hesperus were more abundant at the higher irrigation level (20% SWD) but the predator densities were unaffected by irrigation levels. Both L. hesperus and its predators were affected by the selectivity of the insecticide with highest L. hesperus densities and lowest predator abundance where the broad spectrum insecticide (acephate) was used. There were no direct interactions between irrigation level and insecticides, indicating that insecticide effects on L. hesperus and its predators were not influenced by the irrigation levels used here. The implications of these findings on the overall ecology of insect-plant dynamics and yield in cotton are discussed.

  14. Protective effect and economic impact of insecticide application methods on barley

    Directory of Open Access Journals (Sweden)

    Alfred Stoetzer

    2014-03-01

    Full Text Available The objective of this work was to evaluate the protective effect of different forms of insecticide application on the transmission of yellow dwarf disease in barley cultivars, as well as to determine the production costs and the net profit of these managements. The experiments were carried out during 2011 and 2012 growing seasons, using the following managements at main plots: T1, seed treatment with insecticide (ST + insecticide on shoots at 15-day interval; T2, just ST; T3, insecticide applied on shoots, when aphid control level (CL was reached; T4, without insecticide; and T5, ST + insecticide on shoots when CL was reached. Different barley cultivars - BRS Cauê, BRS Brau and MN 6021 - were arranged in the subplots. Insecticides lambda cyhalothrin (pyrethroid and thiamethoxam (neonicotinoid were used. There were differences on yellow dwarf disease index in both seasons for the different treatments, while damage to grain yield was influenced by year and aphid population. Production costs and net profit were different among treatments. Seed treatment with insecticide is sufficient to reduce the transmission of yellow dwarf disease in years with low aphid population pressure, while in years with larger populations, the application of insecticide on shoots is also required.

  15. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    Directory of Open Access Journals (Sweden)

    Adélaïde Miarinjara

    2016-02-01

    Full Text Available Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines. Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur. Only one insecticide (dieldrin was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  16. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-01-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar. PMID:26844772

  17. A comparison of Drosophila melanogaster detoxification gene induction responses for six insecticides, caffeine and phenobarbital.

    Science.gov (United States)

    Willoughby, Lee; Chung, Henry; Lumb, Chris; Robin, Charles; Batterham, Philip; Daborn, Phillip J

    2006-12-01

    Modifications of metabolic pathways are important in insecticide resistance evolution. Mutations leading to changes in expression levels or substrate specificities of cytochrome P450 (P450), glutathione-S-transferase (GST) and esterase genes have been linked to many cases of resistance with the responsible enzyme shown to utilize the insecticide as a substrate. Many studies show that the substrates of enzymes are capable of inducing the expression of those enzymes. We investigated if this was the case for insecticides and the enzymes responsible for their metabolism. The induction responses for P450s, GSTs and esterases to six different insecticides were investigated using a custom designed microarray in Drosophila melanogaster. Even though these gene families can all contribute to insecticide resistance, their induction responses when exposed to insecticides are minimal. The insecticides spinosad, diazinon, nitenpyram, lufenuron and dicyclanil did not induce any P450, GST or esterase gene expression after a short exposure to high lethal concentrations of insecticide. DDT elicited the low-level induction of one GST and one P450. These results are in contrast to induction responses we observed for the natural plant compound caffeine and the barbituate drug phenobarbital, both of which highly induced a number of P450 and GST genes under the same short exposure regime. Our results indicate that, under the insecticide exposure conditions we used, constitutive over-expression of metabolic genes play more of a role in insect survival than induction of members of these gene families.

  18. Effect of deltamethrin (pyrethroid insecticide) on two clones of Daphnia magna (Crustacea, Cladocera): a proteomic investigation.

    Science.gov (United States)

    Toumi, Héla; Boumaiza, Moncef; Immel, Françoise; Sohm, Bénédicte; Felten, Vincent; Férard, Jean-François

    2014-03-01

    Deltamethrin is a class II pyrethroid insecticide commonly used in agriculture. It is hazardous to freshwater ecosystems, especially for the cladoceran Daphnia magna (Straus 1820). The results of our previous studies based on acute and chronic ecotoxicity experiments revealed differences in the sensitivity between two different clones. In this work, to investigate deltamethrin toxicity mechanisms in two clones of D. magna, we used a proteomic approach in order to analyze changes in protein expression profiles after 48 h of exposure. We detected 1339 spots; then applying statistical criteria (ANOVA pclones. Moreover, using the 2-DIGE method, proteomic investigation for deltamethrin exposure proved to be a reliable and powerful approach to investigate effects of deltamethrin as part of research for new metabolic and cellular biomarkers. After identification by mass spectrometry, there were 39 proteins recognized and identified, in which 21 and 18 were up- and down-regulated, respectively, in deltamethrin-exposed clone A compared to three other conditions (controls of each clone and deltamethrin-exposed clone 2). Up- and down-regulated proteins belonged to 12 biological processes (i.e. metabolic processes, apoptosis and stimulus response) and 5 molecular functions (i.e. catalytic activity, binding, structural molecular activity, antioxidant and receptor activities). Identification of these deregulated proteins opens a new way in discovering new molecular targets and putative biomarkers in daphnids exposed to deltamethrin.

  19. Degradation of Insecticides in Poultry Manure: Determining the Insecticidal Treatment Interval for Managing House Fly (Diptera: Muscidae) Populations in Poultry Farms.

    Science.gov (United States)

    Ong, Song-Quan; Ab Majid, Abdul Hafiz; Ahmad, Hamdan

    2016-04-01

    It is crucial to understand the degradation pattern of insecticides when designing a sustainable control program for the house fly, Musca domestica (L.), on poultry farms. The aim of this study was to determine the half-life and degradation rates of cyromazine, chlorpyrifos, and cypermethrin by spiking these insecticides into poultry manure, and then quantitatively analyzing the insecticide residue using ultra-performance liquid chromatography. The insecticides were later tested in the field in order to study the appropriate insecticidal treatment intervals. Bio-assays on manure samples were later tested at 3, 7, 10, and 15 d for bio-efficacy on susceptible house fly larvae. Degradation analysis demonstrated that cyromazine has the shortest half-life (3.01 d) compared with chlorpyrifos (4.36 d) and cypermethrin (3.75 d). Cyromazine also had a significantly greater degradation rate compared with chlorpyrifos and cypermethrin. For the field insecticidal treatment interval study, 10 d was the interval that had been determined for cyromazine due to its significantly lower residue; for ChCy (a mixture of chlorpyrifos and cypermethrin), the suggested interval was 7 d. Future work should focus on the effects of insecticide metabolites on targeted pests and the poultry manure environment.

  20. Sensitivity of Bemisia tabaci (Hemiptera: Aleyrodidae) to several new insecticides in China: effects of insecticide type and whitefly species, strain, and stage.

    Science.gov (United States)

    Xie, Wen; Liu, Yang; Wang, Shaoli; Wu, Qingjun; Pan, Huipeng; Yang, Xin; Guo, Litao; Zhang, Youjun

    2014-01-01

    Whitefly biotypes B and Q are the two most damaging members of the Bemisia tabaci (Hemiptera: Aleyrodidae) species complex. Control of B. tabaci (and especially of Q) has been impaired by resistance to commonly used insecticides. To find new insecticides for B. tabaci management in China, we investigated the sensitivity of eggs, larvae, and adults of laboratory strains of B and Q (named Lab-B and Lab-Q) and field strains of Q to several insecticides. For eggs, larvae, and adults of B. tabaci and for six insecticides (cyantraniliprole, chlorantraniliprole, pyriproxyfen, buprofezin, acetamiprid, and thiamethoxam), LC50 values were higher for Lab-Q than for Lab-B; avermectin LC50 values, however, were low for adults of both Lab-Q and Lab-B. Based on the laboratory results, insecticides were selected to test against eggs, larvae, and adults of four field strains of B. tabaci Q. Although the field strains differed in their sensitivity to the insecticides, the eggs and larvae of all strains were highly sensitive to cyantraniliprole, and the adults of all strains were highly sensitive to avermectin. The eggs, larvae, and adults of B. tabaci Q were generally more resistant than those of B. tabaci B to the tested insecticides. B. tabaci Q eggs and larvae were sensitive to cyantraniliprole and pyriproxyfen, whereas B. tabaci Q adults were sensitive to avermectin. Field trials should be conducted with cyantraniliprole, pyriproxyfen, and avermectin for control of B. tabaci Q and B in China.

  1. Evaluation of the Pollution of surface waters in the basin of west Algeria by Organo chlorine and Organophosphorus pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Hadjel, M.; Berkok, N.

    2009-07-01

    The pollutants are pesticides which cover a whole range of chemicals designed to protect plants from pests and destroy unwanted plants. There are a very large number of pesticides and we do here that some of the major families (organo chlorine insecticides, organophosphates, carbamates, pyrethroids, phenylcyclohexyl, herbicides. (Author)

  2. Exposure to the mixture of organophosphorus pesticides is embryotoxic and teratogenic on gestational rats during the sensitive period.

    Science.gov (United States)

    Yu, Yan; Yang, Yuxuan; Zhao, Xiaodan; Liu, Xiaofei; Xue, Jianjun; Zhang, Jinghua; Yang, Aimin

    2017-01-01

    Mixture of organophosphorus pesticides (MOPs) has been used worldwide to increase food production. The MOPs are harmful, and the exposure to them is both agricultural and nonagricultural through contaminated food. The neurotoxicity of MOPs has received more consideration recently due to the increased cases of malformed fetuses suspected to be caused by the MOPs exposure during gestation; however, relevant studies in animal model are rare. In this study, we performed a comprehensive analysis and demonstrated potential perinatal embryotoxicity and teratogenicity of MOPs exposure. As results, we found that MOPs decreased in utero fetal growth and alter the ratio of organs to whole body weight of the pregnant rats. MOPs also had been shown to disturb the balance of sex hormones and affect the reproduction of rats. Furthermore, we found various significantly elevated deformities in MOPs exposed embryos, confirming the embryotoxic and teratogenic effects of maternal exposure to MOPs. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 139-146, 2017.

  3. Rational design of organophosphorus hydrolase with high catalytic efficiency for detoxifying a V-type nerve agent.

    Science.gov (United States)

    Jeong, Young-Su; Choi, Jung Min; Kyeong, Hyun-Ho; Choi, Jae-Youl; Kim, Eui-Joong; Kim, Hak-Sung

    2014-07-01

    V-type nerve agents, known as VX, are organophosphate (OP) compounds, and show extremely toxic effects on human and animals by causing cholinergic overstimulation of synapses. The bacterial organophosphorus hydrolase (OPH) has attracted much attention for detoxifying V-type agents through hydrolysis of the P-S bond. However, low catalytic efficiency of OPH has limited the practical use of the enzyme. Here we present rational design of OPH with high catalytic efficiency for a V-type nerve agent. Based on the model structure of the enzyme and substrate docking simulation, we predicted the key residues that appear to enhance the access of the substrate to the active site of the enzyme, and constructed numerous OPH mutants. Of them, double mutant, L271/Y309A, was shown to exhibit a 150-fold higher catalytic efficiency for VX than the wild-type.

  4. Degradation of Organophosphorus Pesticides in Water during UV/H2O2 Treatment: Role of Sulphate and Bicarbonate Ions

    Directory of Open Access Journals (Sweden)

    Am Fadaei

    2012-01-01

    Full Text Available The photodegradation of two organophosphorus pesticides, malathian and diazinon, by sulfate radicals and bicarbonate radicals in aqueous solution were studied. The effect of the operational parameters such as pH, salt concentration, water type, H2O2 concentration and initial concentration of pesticides was studied. Gas chromatography mass spectroscopy (GC–MS was used for analyses of pesticides. When salt effect was studied, it was found that sodium bicarbonate was the most powerful inhibitor used, while sodium sulfate was the weakest one. The highest degradation in UV/H2O2 process for malathion was found in alkaline condition and for diazinon in acidic condition. The photodegradation in all waters used in this work exhibited first order kinetics. Photodegradation rate in distilled water was higher than real water. The degradation of pesticides increased with increasing of H2O2 concentration.

  5. Towards a Capacitive Enzyme Sensor for Direct Determination of Organophosphorus Pesticides: Fundamental Studies and Aspects of Development

    Directory of Open Access Journals (Sweden)

    Ashok Mulchandani

    2003-06-01

    Full Text Available The realisation of a miniaturised potentiometric enzyme biosensor is presented. The biosensor chip utilises the enzyme organophosphorus hydrolase (OPH for the direct determination of pesticides. The transducer structure of the sensors chip consists of a pH-sensitive capacitive electrolyte-insulator-semiconductor (EIS structure that reacts towards pH changes caused by the OPH-catalised hydrolysis of the organophosphate compounds. The biosensor is operated versus a conventional Ag/AgCl reference electrode. Measurements were performed in the capacitance/voltage (C/V and the constant capacitance (ConCap mode for the two different pesticides paraoxon and parathion. For the development of this new type of biosensor, different immobilisation strategies, influence of buffer composition and concentration, transducer material, detection limit, long-term stability and selectivity have been studied.

  6. Inhibition of acetylcholinesterase activity in the terrestrial isopod Porcellio scaber as a biomarker of organophosphorus compounds in food.

    Science.gov (United States)

    Stanek, Katja; Gabrijelcic, Elizabeta; Drobne, Damjana; Trebse, Polonca

    2003-09-01

    This paper describes the toxicity of organophosphorus pesticide diazinon in juvenile and adult terrestrial isopods Porcellio scaber (Isopoda, Crustacea). The woodlice were exposed to different concentrations of diazinon added to food (5, 10, 50, and 100 or 150 micrograms/g dry food). Weight change and food assimilation efficiency were determined two and four weeks after the exposure. The activity of acetylcholinesterase (AChE) in surviving animals was measured at the end of the experiment. The results show that woodlice exposed to diazinon do not significantly differ from controls in growth and feeding rate. The reduction of AChE activity was observed at the lowest diazinon exposure (5 and 10 micrograms/g dry food). These results suggest that AChE activity might prove a useful biomarker, indicating low levels of organophosphates in food.

  7. Analysis of six organophosphorus pesticide residues in apples and pears using cloud-point extraction coupled with HPLC-UV.

    Science.gov (United States)

    Zhang, Lijin; Chen, Fang; Zhang, Wenhuan; Pan, Canping

    2014-01-01

    A cloud-point extraction (CPE) method with Triton X-114 has been developed for analysis of six organophosphorus pesticides (OPPs) in apples and pears. In this CPE procedure, the effects of the surfactant volume, mass of sodium chloride, equilibrium temperature, equilibrium time, and pH on the extraction procedure were investigated. Under the optimal CPE conditions, the analytes were enriched 20-fold and the LODs dropped to 0.44-5.20 microg/kg. Furthermore, the proposed extraction method was validated by the correlation coefficient (R2) of the calibration curve, repeatability (RSD, n = 6), and fortified recoveries, which were 0.9967-0.9993, 2.7-6.5, and 74.7-104.5%, respectively. Based on these results, it could be concluded that the proposed CPE method with Triton X-114 was suitable for the effective extraction and enrichment of OPP residues in the apple and pear samples.

  8. Liquid chromatography tandem mass spectrometry applied to quantitation of the organophosphorus nerve agent VX in microdialysates from blood probes.

    Science.gov (United States)

    Stubbs, S J; Read, R W

    2010-05-15

    VX (O-ethyl-S-[2(di-isopropylamino)ethyl] methylphosphonothiolate) is a low volatility organophosphorus (OP) nerve agent and therefore the most likely route of exposure is via percutaneous absorption. Microdialysis has been used as a tool to study percutaneous poisoning by VX in the anesthetised guinea pig. A liquid chromatography tandem mass spectrometry (LC-MS-MS) method using positive electrospray ionisation (ESI) was used to quantitate VX in microdialysate samples collected from microdialysis probes, implanted into a blood vessel of anesthetised guinea pigs. The method resulted from modification of a LC-MS-MS method previously developed for the analysis of dermal microdialysates. Modification increased the sensitivity of the method, allowing quantitation of the trace levels of VX in blood microdialysates, over the range 0.002-1 ng/ml, with linear calibration. Quantitative results have been used to determine the time course of VX concentrations in the blood of guinea pigs following percutaneous poisoning.

  9. Determination of no-observed effect level (NOEL-biomarker equivalents to interpret biomonitoring data for organophosphorus pesticides in children

    Directory of Open Access Journals (Sweden)

    Bouchard Michèle

    2009-02-01

    Full Text Available Abstract Background Environmental exposure to organophosphorus pesticides has been characterized in various populations, but interpretation of these data from a health risk perspective remains an issue. The current paper proposes biological reference values to help interpret biomonitoring data related to an exposure to organophosphorus pesticides in children for which measurements of alkylphosphate metabolites are available. Methods Published models describing the kinetics of malathion and chlorpyrifos in humans were used to determine no-observed effect level – biomarker equivalents for methylphosphates and ethylphosphates, respectively. These were expressed in the form of cumulative urinary amounts of alkylphosphates over specified time periods corresponding to an absorbed no-observed effect level dose (derived from a published human exposure dose and assuming various plausible exposure scenarios. Cumulative amounts of methylphosphate and ethylphosphate metabolites measured in the urine of a group of Quebec children were then compared to the proposed biological reference values. Results From a published no-observed effect level dose for malathion and chlorpyrifos, the model predicts corresponding oral biological reference values for methylphosphate and ethylphosphate derivatives of 106 and 52 nmol/kg of body weight, respectively, in 12-h nighttime urine collections, and dermal biological reference values of 40 and 32 nmol/kg of body weight. Out of the 442 available urine samples, only one presented a methylphosphate excretion exceeding the biological reference value established on the basis of a dermal exposure scenario and none of the methylphosphate and ethylphosphate excretion values were above the obtained oral biological reference values, which reflect the main exposure route in children. Conclusion This study is a first step towards the development of biological guidelines for organophophorus pesticides using a toxicokinetic modeling

  10. Efficient Surface Display of Diisopropylfluorophosphatase (DFPase) in E. coli for Biodegradation of Toxic Organophosphorus Compounds (DFP and Cp).

    Science.gov (United States)

    Latifi, Ali Mohammad; Karami, Ali; Khodi, Samaneh

    2015-10-01

    Compounds including organophosphorus pesticides (OPs) and chemical nerve agents are toxic compounds synthesized recently which disrupt the mechanisms of neural transmission. Therefore, a critical requirement is the development of a bio-refining technology to facilitate the biodegradation of organophosphorus pollutants. The diisopropylfluorophosphatase (DFPase, EC 3.1.8.2) from the ganglion and brain of Loligo vulgaris acts on P-F bonds present in some OPs. Intracellular production of OPs-degrading enzymes or the use of native bacteria and fungi leads to a low degradation rate of OPs due to a mass transfer issue which reduces the overall catalytic efficiency. To overcome this challenge, we expressed DFPase on the surface of E. coli for the first time by employing the N-terminal domain of the ice nucleation protein (InaV-N) as an anchoring motif. Tracking the recombinant protein confirmed that DFPase is successfully located on the outer membrane. Further studies on its activity to degrade diisopropylfluorophosphate (DFP) showed its significant ability for the biodegradation of diisopropylfluorophosphate (DFP) with a specific activity of 500 U/mg of wet cell weight. Recombinant cells could also degrade chlorpyrifos (Cp) with an activity equivalent to a maximum value of 381.44 U/ml with a specific activity of 476.75 U/mg of cell, analyzed using HPLC technique. The optimum activity of purified DFPase was found at 30 °C. A more increased activity was also obtained in the presence of glucose-mineral-salt (GMS) supplemented with tryptone and 100 mg/L Co(2+) ion. These results highlight the high potential of the InaV-N anchoring domain to produce an engineered bacterium that can be used in the bioremediation of pesticide-contaminated environments.

  11. Management of Treatment and Prevention of Acute OP Pesticide Poisoning by Medical Informatics, Telemedicine and Nanomedicine

    Directory of Open Access Journals (Sweden)

    Ganesh Chandra Sahoo

    2013-10-01

    Full Text Available Acute organophosphorous pesticide (OP poisoning kills a lot of people each year. Treatment of acute OP poisoning is of very difficult task and is a time taking event. Present day informatics methods (telemedicine, bioinformatics methods (data mining, molecular modeling, docking, cheminformatics, and nanotechnology (nanomedicine should be applied in combination or separately to combat the rise of death rate due to OP poisoning. Use of informatics method such as Java enabled camera mobiles will enable us early detection of insecticidal poisoning. Even the patients who are severely intoxicated (suicidal attempts can be diagnosed early. Telemedicine can take care for early diagnosis and early treatment. Simultaneously efforts must be taken with regard to nanotechnology to find lesser toxic compounds (use less dose of nanoparticle mediated compounds: nano-malathion as insecticides and find better efficacy of lesser dose of compounds for treatment (nano-atropine of OP poisoning. Nano-apitropine (atropine oxide may be a better choice for OP poisoning treatment as the anticholinergic agent; apitropine and hyoscyamine have exhibited higher binding affinity than atropine sulfate. Synthesis of insecticides (malathion with an antidote (atropine, apitropine in nanoscale range will prevent the lethal effect of insecticides.

  12. [Advances in effects of insecticidal crystal proteins released from transgenic Bt crops on soil ecology].

    Science.gov (United States)

    Zhou, Xue-Yong; Liu, Ning; Zhao, Man; Li, He; Zhou, Lang; Tang, Zong-Wen; Cao, Fei; Li, Wei

    2011-05-01

    With the large scale cultivation of transgenic crops expressing Bacillus thuringiensis (Bt) insecticidal crystal proteins in the world, the problem of environmental safety caused by these Bt crops has received extensive attention. These insecticidal crystal proteins can be released into the soil continuously in the growing period of Bt plants. If their accumulation of the insecticidal crystal proteins exceeds consumption by insect larvae and degradation by the environmental factors, these insecticidal crystal proteins could constitute a hazard to non-target insects and soil microbiota. There are three main ways to release insecticidal crystal proteins into soil for Bt plants: root exudates, pollen falling, and crop reside returning. The Bt insecticidal crystal proteins released into soil can be adsorbed rapidly by active soil particles and the absorption equilibrium attained within 1-3 h. The adsorption protects Bt insecticidal crystal proteins against soil microbial degradation or enzyme degradation, which leads to remarkable prolong of the persistence of insecticidal activity. The change of soil microorganism species is an important index for evaluating the effect of Bt plants on soil ecology. The research showed that these insecticidal crystal proteins released by the Bt plant root exudates or Bt organism had no toxicity to the soil earthworms, nematodes, protozoa, bacteria and fungi; however, it could reduce the mycelium length of the arbuscular mycorrhizal fungi (AMF) and restrain AMF to form invasion unit. The influencing degree of Bt protein on soil enzyme activity varied with the releasing modes or growth period of Bt crops. Bt Cry1Ab protein can be taken up from soil by parts of following crops; however, different results were obtained with different commercial kits. To better understand the soil ecological evaluation about the insecticidal crystal proteins released from transgenic Bt crops, this review provides a comprehensive overview about the release

  13. Impact of reduced-risk insecticides on soybean aphid and associated natural enemies.

    Science.gov (United States)

    Ohnesorg, Wayne J; Johnson, Kevin D; O'Neal, Matthew E

    2009-10-01

    Insect predators in North America suppress Aphis glycines Matsumura (Hemiptera: Aphididae) populations; however, insecticides are required when populations reach economically damaging levels. Currently, insecticides used to manage A. glycines are broad-spectrum (pyrethroids and organophosphates), and probably reduce beneficial insect abundance in soybean, Glycine max (L.) Merr. Our goal was to determine whether insecticides considered reduced-risk by the Environmental Protection Agency could protect soybean yield from A. glycines herbivory while having a limited impact on the aphid's natural enemies. We compared three insecticides (imidacloprid, thiamethoxam, and pymetrozine,) to a broad-spectrum insecticide (lamda-cyhalothrin) and an untreated control using two application methods. We applied neonicotinoid insecticides to seeds (imidacloprid and thiamethoxam) as well as foliage (imidacloprid); pymetrozine and lamda-cyhalothrin were applied only to foliage. Foliage-applied insecticides had lower A. glycines populations and higher yields than the seed-applied insecticides. Among foliage-applied insecticides, pymetrozine and imidacloprid had an intermediate level of A. glycines population and yield protection compared with lamda-cyhalothrin and the untreated control. We monitored natural enemies with yellow sticky cards, sweep-nets, and direct observation. Before foliar insecticides were applied (i.e., before aphid populations developed) seed treatments had no observable effect on the abundance of natural enemies. After foliar insecticides were applied, differences in natural enemy abundance were observed when sampled with sweep-nets and direct observation but not with yellow sticky cards. Based on the first two sampling methods, pymetrozine and the foliage-applied imidacloprid had intermediate abundances of natural enemies compared with the untreated control and lamda-cyhalothrin.

  14. Acute toxicity of organochlorine insecticide endosulfan to the giant freshwater prawn Macrobrochium rosenbergii

    Science.gov (United States)

    Dai, Xilin; Xiong, Zhaodi; Xie, Jian; Ding, Fujiang

    2014-01-01

    Endosulfan, an organochlorine pesticide, is highly toxic and effective at controlling pests in agriculture, horticulture, and public health programs. In this study, static bioassays were used to evaluate the toxicity of endosulfan to freshwater prawns ( Macrobrachium rosenbergii) of various lengths (1.5±0.03, 4±0.08, and 7±0.06 cm). Additionally, the activities of peroxidase (POD), acid phosphatase (ACP), alkaline phosphatase, acetylcholinesterase (AChE), and Na+/K+-ATPase were analyzed to reflect the effects of endosulfan exposure. The 96 h LC50 of endosulfan for prawns 1.5, 4, and 7 cm long were 1.86, 4.53, and 6.09 μg/L, respectively, improved tolerance to endosulfan with growth. The POD activities of test organisms exposed to low concentrations of endosulfan were inhibited, indicating the presence of oxygen damaged tissue. Moreover, a notable decrease in AChE activity was observed due to overstimulation of neurotransmission, which might result in abnormal behavior. The effect caused by endosulfan on phosphatase production in the hepatopancreas of prawns 1.5, 4, and 7 cm long was different because the ability of nonspecific immune regulation increased with growth. The 96 h LC50 values obtained in this study could be used in the formulation of water-quality criteria in China. Moreover, the changes in enzymes activities of M. rosenbergii under stress of endosulfan could be applied in the establishment of early warning indicators for bio-safety.

  15. Investigation of acute toxicity of pirimiphos-methyl (Actellic, 25%EC) on guppy (Poecilia reticulata, Peters, 1859).

    Science.gov (United States)

    Lawal, M O; Samuel, O B

    2010-04-15

    Pirimiphos-methyl is a broad spectrum organophosphate insecticide and potential toxic pollutant in aquatic ecosystems. The acute toxicity of Pirimiphos-methyl (Actellic) was investigated using Guppy (Poecilia reticulata) in a 96 h static renewal laboratory bioassay. Based on probit analysis the LC50 was 0.026, 0.024, 0.022 and 0.019 ml L(-1) at 24, 48, 72 and 96 h, respectively. Analysis of Variance (ANOVA) showed that there was significant difference (p reticulata to different concentrations of Actellic at 24, 48, 72 and 96 h of exposure. Actellic insecticide is toxic to fish; therefore its indiscriminate use in aquatic environment should be discouraged.

  16. Investigation on possible ecotoxicological risk of carbofuran insecticides.

    Science.gov (United States)

    Lehel, J; Déri, J; Laczay, P; Darin, E G; Budai, P; Kormos, E

    2010-01-01

    Carbofuran-containing insecticides are widely used agents in plant protection. Their use may pose considerable environmental risk for both the protected and non-protected predator and plantivorous birds. For defence of wild birds a model experiment was carried out on broiler chickens. In the study, eight animals were treated orally by gastric tube with a carbofuran-containing insecticide at a single dose of 2.5 mg/kg b.w. One animal served as untreated control specimen. Forage and drinking water were provided ad libitum. After the treatment, the possible clinical signs were observed carefully, blood samples were obtained from each bird and after exsanguinations liver, breast and leg muscle samples and stomach content were taken. The carbofuran concentration in blood, tissues and stomach content was determined by gas chromatographic method. Thirty minutes after poisoning, the average carbofuran concentration in breast muscle of chickens exceeded the maximum level of 0.1 mg/kg permitted in edible tissues, whereas ninety minutes after poisoning the concentration of one sample was still above the limit value. In the liver, leg-muscle and blood samples, the measured carbofuran concentration was lower than the permitted maximum value, except in the blood of two animals. The carbofuran concentration of the stomach content markedly exceeded the limit value. The sublethal concentration of the pesticides can reduce the capable of living of wild animals. Due to the sub toxic dose the poisoned birds can survive; however, the residue of insecticides can lead to secondary toxicosis of other animals.

  17. Insecticidal and fungicidal activity of new synthesized chitosan derivatives.

    Science.gov (United States)

    Rabea, Entsar I; Badawy, Mohamed E I; Rogge, Tina M; Stevens, Christian V; Höfte, Monica; Steurbaut, Walter; Smagghe, Guy

    2005-10-01

    Chitosan, the N-deacetylated derivative of chitin, is a potential biopolysaccharide owing to its specific structure and properties. In this paper, we report on the synthesis of 24 new chitosan derivatives, N-alkyl chitosans (NAC) and N-benzyl chitosans (NBC), that are soluble in dilute aqueous acetic acid. The different derivatives were synthesized by reductive amination and analyzed by 1H NMR spectroscopy. A high degree of substitution (DS) was obtained with N-(butyl)chitosan (DS 0.36) at a 1:1 mole ratio for NAC derivatives and N-(2,4-dichlorobenzyl)chitosan (DS 0.52) for NBC derivatives. Their insecticidal and fungicidal activities were tested against larvae of the cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), the grey mould Botrytis cinerea Pers (Leotiales: Sclerotiniaceae) and the rice leaf blast Pyricularia grisea Cavara (Teleomorph: Magnaporthe grisea (Hebert) Barr). The oral feeding bioassay indicated that all the derivatives had significant insecticidal activity at 5 g kg(-1) in artificial diet. The most active was N-(2-chloro-6-fluorobenzyl)chitosan, which caused 100% mortality at 0.625 g kg(-1), with an estimated LC50 of 0.32 g kg(-1). Treated larvae ceased feeding after 2-3 days; the mechanism of action remains unknown. In a radial hyphal growth bioassay with both plant pathogens, all derivatives showed a higher fungicidal action than chitosan. N-Dodecylchitosan, N-(p-isopropylbenzyl)chitosan and N-(2,6-dichlorobenzyl)chitosan were the most active against B cinerea, with EC50 values of 0.57, 0.57 and 0.52 g litre(-1), respectively. Against P grisea, N-(m-nitrobenzyl)chitosan was the most active, with 77% inhibition at 5 g litre(-1). The effect of different substitutions is discussed in relation to insecticidal and fungicidal activity.

  18. Developmental neurotoxicity of pyrethroid insecticides in zebrafish embryos.

    Science.gov (United States)

    DeMicco, Amy; Cooper, Keith R; Richardson, Jason R; White, Lori A

    2010-01-01

    Pyrethroid insecticides are one of the most commonly used residential and agricultural insecticides. Based on the increased use of pyrethroids and recent studies showing that pregnant women and children are exposed to pyrethroids, there are concerns over the potential for developmental neurotoxicity. However, there have been relatively few studies on the developmental neurotoxicity of pyrethroids. In this study, we sought to investigate the developmental toxicity of six common pyrethroids, three type I compounds (permethrin, resmethrin, and bifenthrin) and three type II compounds (deltamethrin, cypermethrin, and lambda-cyhalothrin), and to determine whether zebrafish embryos may be an appropriate model for studying the developmental neurotoxicity of pyrethroids. Exposure of zebrafish embryos to pyrethroids caused a dose-dependent increase in mortality and pericardial edema, with type II compounds being the most potent. At doses approaching the LC(50), permethrin and deltamethrin caused craniofacial abnormalities. These findings are consistent with mammalian studies demonstrating that pyrethroids are mildly teratogenic at very high doses. However, at lower doses, body axis curvature and spasms were observed, which were reminiscent of the classic syndromes observed with pyrethroid toxicity. Treatment with diazepam ameliorated the spasms, while treatment with the sodium channel antagonist MS-222 ameliorated both spasms and body curvature, suggesting that pyrethroid-induced neurotoxicity is similar in zebrafish and mammals. Taken in concert, these data suggest that zebrafish may be an appropriate alternative model to study the mechanism(s) responsible for the developmental neurotoxicity of pyrethroid insecticides and aid in identification of compounds that should be further tested in mammalian systems.

  19. Synergy in efficacy of fungal entomopathogens and permethrin against West African insecticide-resistant Anopheles gambiae mosquitoes

    NARCIS (Netherlands)

    Farenhorst, M.; Knols, B.G.J.; Thomas, M.B.; Howard, A.F.V.; Takken, W.; Rowland, M.; N'Guessan, R.

    2010-01-01

    Background Increasing incidences of insecticide resistance in malaria vectors are threatening the sustainable use of contemporary chemical vector control measures. Fungal entomopathogens provide a possible additional tool for the control of insecticide-resistant malaria mosquitoes. This study invest

  20. Natural product derived insecticides: discovery and development of spinetoram.

    Science.gov (United States)

    Galm, Ute; Sparks, Thomas C

    2016-03-01

    This review highlights the importance of natural product research and industrial microbiology for product development in the agricultural industry, based on examples from Dow AgroSciences. It provides an overview of the discovery and development of spinetoram, a semisynthetic insecticide derived by a combination of a genetic block in a specific O-methylation of the rhamnose moiety of spinosad coupled with neural network-based QSAR and synthetic chemistry. It also emphasizes the key role that new technologies and multidisciplinary approaches play in the development of current spinetoram production strains.