WorldWideScience

Sample records for carbamate pesticides validation

  1. Carbamate pesticide induced toxic epidermal necrolysis

    Directory of Open Access Journals (Sweden)

    Rajendran N

    2001-09-01

    Full Text Available A 36-year-old male alleged to have consumed carbamate pesticide liquid (Baygon@ developed toxic epidermal necrolysis (TEN within twenty-four hours of intake. Though drugs have been commonly incriminated as offending agents for TEN, carbamate pesticide was found to be the causative agent in our case.

  2. Analysis of Carbamate Pesticides: Validation of Semi-Volatile Analysis by HPLC-MS/MS by EPA Method MS666

    Energy Technology Data Exchange (ETDEWEB)

    Owens, J; Koester, C

    2008-05-14

    The Environmental Protection Agency's (EPA) Region 5 Chicago Regional Laboratory (CRL) developed a method for analysis of aldicarb, bromadiolone, carbofuran, oxamyl, and methomyl in water by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS), titled Method EPA MS666. This draft standard operating procedure (SOP) was distributed to multiple EPA laboratories and to Lawrence Livermore National Laboratory, which was tasked to serve as a reference laboratory for EPA's Environmental Reference Laboratory Network (ERLN) and to develop and validate analytical procedures. The primary objective of this study was to validate and verify the analytical procedures described in MS666 for analysis of carbamate pesticides in aqueous samples. The gathered data from this validation study will be used to: (1) demonstrate analytical method performance; (2) generate quality control acceptance criteria; and (3) revise the SOP to provide a validated method that would be available for use during a homeland security event. The data contained in this report will be compiled, by EPA CRL, with data generated by other EPA Regional laboratories so that performance metrics of Method EPA MS666 can be determined.

  3. CUMULATIVE EFFECTS OF ORGANOPHOSPHORUS OR CARBAMATE PESTICIDES.

    Science.gov (United States)

    This book chapter strives to summarize the body of literature exploring the toxic interaction of organophosphorus and carbamate pesticides in mixtures. This review represents one of the only reviews of the subject that has been published within the last 20 years. Specifically, th...

  4. Wildlife mortality attributed to organophosphorus and carbamate pesticides

    Science.gov (United States)

    Glaser, L.C.

    1995-01-01

    Organophosphorus (OP) and carbamate pesticides are used widely in agricultural and residential applications as insecticides, herbicides, fungicities. and rodenticides. This family of chemicals replaced the organochlorine pesticides banned for use in the United States in the 1970's. Unlike organochlorine pesticides, which are long-lived in the environment and cause biological damage when they accumulate in an organism's system over time. OP and carbamate pesticides are short-lived in the environment and fast-acting on their 'target pest.' Direct mortality of wildlife from organochlorine pesticides was uncommon (Hayes and Wayland 1975): however, mortality is the primary documented effect on wildlife from OP and carbamate pesticides (Grue et al. 1983). Organophosphorus and carbamate pesticide toxicity is not specific to a target 'pest,' and lethal effects are seen in nontarget organisms: birds appear to be the most sensitive class of animals affected by these pesticides. Organophosphorus and carbamate pesticides primainly affect the nervous system by inhibiting acetylcholinesterase (AChE) enzyme activity. This enzyme's main function in the nervous system is to break down the neurotransmitter acetylcholine. When AChE is altered by OP and carbamate pesticides, it cannot perform this breakdown function and acetylcholine accumulates. Acetylcholine accumulation increases nerve impulse transmission and leads to nerve exhaustion and. ultimately, failure of the nervous system. When the nervous system fails, muscles do not receive the electrical input they require to move. The respiratory muscles are the most critical muscle group affected, and respiratory paralysis is often the immediate cause of death.

  5. Induction of Tibial Dyschondroplasia by Carbamate and Thiocarbamate Pesticides

    Science.gov (United States)

    Tibial dyschondroplasia (TD) is a major poultry leg problem the natural etiology of which is unknown. Certain dithiocarbamate pesticides such as tetramethyl thiuram disulfide (thiram) have been shown to induce the disease in chickens. Since many different carbamate and thiocarbamate chemicals are ...

  6. Carbamate Pesticide-Induced Apoptosis in Human T Lymphocytes

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    Qing Li

    2015-04-01

    Full Text Available We previously found that carbamate pesticides induced significant apoptosis in human natural killer cells. To investigate whether carbamate pesticides also induce apoptosis in human T lymphocytes, in the present study Jurkat human T cells were treated in vitro with thiram, maneb, carbaryl or ziram. Apoptosis was determined by FITC-Annexin-V/PI staining. To explore the mechanism of apoptosis, intracellular levels of active caspase 3 and mitochondrial cytochrome-c release were determined by flow cytometry. We found that thiram, ziram, maneb and carbaryl also induced apoptosis in a time- and dose-dependent manner in the human T cells. However, the strength of the apoptosis-inducing effect differed among the pesticides, with the: thiram > ziram > maneb > carbaryl. Moreover, thiram significantly increased the intracellular level of active caspase 3 and caspase inhibitors significantly inhibited apoptosis. Thiram also significantly caused mitochondrial cytochrome-c release. These findings indicate that carbamate pesticides can induce apoptosis in human T cells, and the apoptosis is mediated by the activation of caspases and the release of mitochondrial cytochrome-c.

  7. Piezoelectric Biosensors for Organophosphate and Carbamate Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Giovanna Marrazza

    2014-09-01

    Full Text Available Due to the great amount of pesticides currently being used, there is an increased interest for developing biosensors for their detection. Among all the physical transducers, piezoelectric systems have emerged as the most attractive due to their simplicity, low instrumentation costs, possibility for real-time and label-free detection and generally high sensitivity. This paper presents an overview of biosensors based on the quartz crystal microbalance, which have been reported in the literature for organophosphate and carbamate pesticide analysis.

  8. Biodegradation of a carbamate pesticide, Propoxur, in rat tissues.

    Science.gov (United States)

    Kumar, R; Madhavi, N B; Sharma, C B

    1993-01-01

    Propoxur (Baygon, 2-isopropoxyphenyl N-methylcarbamate) is a carbamate pesticide commonly used against house insects. When the insecticide was administered intramuscularly in rats it was converted to a new metabolite which was found to be present in the serum, liver, kidney and brain 6 h after the administration of the pesticide. The metabolite was purified by high performance liquid to chromatography and comparison of the infrared spectra of Propoxur and the metabolite showed that a deamination reaction was responsible for the formation of the metabolite from the parent pesticide. The pesticide also induced haematological changes such as an increased level of total bilubrin, amylase and glutamic-oxalacetic transaminase and decrease of cholinesterase activity, indicating damage of the liver and nervous system in rats.

  9. 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

    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......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...... 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...

  10. DOSE-RESPONSE MODELING FOR THE ASSESSMENT OF CUMULATIVE RISK DUE TO EXPOSURE TO N-METHYL CARBAMATE PESTICIDES

    Science.gov (United States)

    The US EPAs N-Methyl Carbamate Cumulative Risk Assessment (NMCRA) assesses the effect on acetylcholine esterase (AChE) activity of exposure to 10 N-methyl carbamate (NMC) pesticides through dietary, drinking water, and residential exposures.

  11. Photochemical decomposition of carbamate pesticides in natural waters of northern Greece

    International Nuclear Information System (INIS)

    The photochemical decomposition of the carbamate pesticides carbofuran, carbaryl and thiram was examined in natural waters of northern Greece under the influence of solar and UV (λ > 290 nm) radiation. Different major photoproducts were detected by GC/MS. The result of continuous irradiation was almost total degradation of the pesticides examined

  12. 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

    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......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...... exposure was apple. The results show that there is no cumulative acute risk for Danish consumers to acetylcholinesterase- inhibiting pesticides....

  13. Biodegradation of carbamate pesticides by natural river biofilms in different seasons and their effects on biofilm community structure

    International Nuclear Information System (INIS)

    This study investigated the ability of natural river biofilms from different seasons to degrade the carbamate pesticides methomyl, carbaryl and carbofuran in single and multiple pesticide systems, and the effects of these pesticides on algal and bacterial communities within biofilms. Spring biofilms had the lowest biomass of algae and bacteria but showed the highest methomyl degradation (>99%) and dissipation rates, suggesting that they might contain microorganisms with high methomyl degradation abilities. Degradation of carbofuran (54.1–59.5%) by biofilms in four seasons was similar, but low degradation of carbaryl (0–27.5%) was observed. The coexistence of other pesticides was found to cause certain effects on pesticide degradation and primarily resulted in lower diversity of diatoms and bacteria than when using a single pesticide. The tolerant diatoms and bacteria potentially having the ability to degrade test pesticides were identified. River biofilms could be suitable biomaterials or used to isolate degraders for bioremediating pesticide-contaminated water. -- Highlights: •Natural river biofilms showed high ability to degrade methomyl and carbofuran. •The presence of other pesticides caused certain effects on pesticide degradation. •Carbamate pesticides caused adverse effects on communities of diatoms and bacteria. •The tolerant diatoms and bacteria were found as potential pesticide-degraders. -- Biodegradation of carbamate pesticides by river biofilms

  14. Investigation of kinetic interactions between approved oximes and human acetylcholinesterase inhibited by pesticide carbamates.

    Science.gov (United States)

    Wille, Timo; Kaltenbach, Lisa; Thiermann, Horst; Worek, Franz

    2013-12-01

    Carbamates are widely used for pest control and act primarily by inhibition of insect and mammalian acetylcholinesterase (AChE). Accidental or intentional uptake of carbamates may result in typical signs and symptoms of cholinergic overstimulation which cannot be discriminated from those of organophosphorus pesticide poisoning. There is an ongoing debate whether standard treatment with atropine and oximes should be recommended for human carbamate poisoning as well, since in vitro and in vivo animal data indicate a deleterious effect of oximes when used in combination with the N-methyl carbamate carbaryl. Therefore, we performed an in vitro kinetic study to investigate the effect of clinically used oximes on carbamoylation and decarbamoylation of human AChE. It became evident that pralidoxime and obidoxime in therapeutic concentrations aggravate the inhibition of AChE by carbaryl and propoxur, with obidoxime being substantially more potent compared to 2-PAM. However, obidoxime had no impact on the decarbamoylation kinetics. Hence, the administration of 2-PAM and especially of obidoxime to severely propoxur and carbaryl poisoned humans cannot be recommended.

  15. Assessment of Organophosphate and Carbamate Pesticide Residues in Cigarette Tobacco with a Novel Cell Biosensor

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    Spiridon Kintzios

    2008-04-01

    Full Text Available The conventional analysis of pesticide residues in analytical commodities, such as tobacco and tobacco products is a labor intensive procedure, since it is necessary to cover a wide range of different chemicals, using a single procedure. Standard analysis methods include extensive sample pretreatment (with solvent extraction and partitioning phases and determination by GC and HPLC to achieve the necessary selectivity and sensitivity for the different classes of compounds under detection. As a consequence, current methods of analysis provide a limited sample capacity. In the present study, we report on the development of a novel cell biosensor for detecting organophosphate and carbamate pesticide residues in tobacco. The sensor is based on neuroblastoma N2a cells and the measurement of changes of the cell membrane potential, according to the working principle of the Bioelectric Recognition Assay (BERA. The presence of pesticide residues is detected by the degree of inhibition of acetylcholine esterase (AChE. The sensor instantly responded to both the organophoshate pesticide chlorpyriphos and the carbamate carbaryl in a concentration-dependent pattern, being able to detect one part per billion (1 ppb. Additionally, tobacco leaf samples (in blended dry form were analyzed with both the novel biosensor and conventional methods, according to a double-blind protocol. Pesticide residues in tobacco samples caused a considerable cell membrane hyperpolarization to neuroblastoma cells immobilized in the sensor, as indicated by the increase of the negative sensor potential, which was clearly distinguishable from the sensor’s response against pesticide-free control samples. The observed response was quite reproducible, with an average variation of +5,6%. Fluorescence microscopy observations showed that treatment of the cells with either chlorpyrifos or carbaryl was associated with increased [Ca2+]cyt . The novel biosensor offers fresh

  16. 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.

  17. Role of B-esterases in assessing toxicity of organophosphorus (chlorpyrifos, malathion) and carbamate (carbofuran) pesticides to Daphnia magna.

    Science.gov (United States)

    Barata, Carlos; Solayan, Arun; Porte, Cinta

    2004-02-10

    In this study, the cladoceran Daphnia magna was exposed to two model organophosphorous and one carbamate pesticides including malathion, chlorpyrifos and carbofuran to assess acetylcholinesterase (AChE) and carboxylesterase (CbE) inhibition and recovery patterns and relate those responses with individual level effects. Our results revealed differences in enzyme inhibition and recovery patterns among the studied esterase enzymes and pesticides. CbE was more sensitive to organophosphorous than AChE, whereas both CbE and AChE showed equivalent sensitivities to the carbamate carbofuran. Recovery patterns of AChE and CbE activities following exposure to the studied pesticides were similar with 80-100% recoveries taking place 12 and 96 h after exposure to organophosphorous and carbamates pesticides, respectively. The physiological role of AChE and CbE inhibition patterns in Daphnia was examined by using organophosphorous and carbamate compounds alone and with specific inhibitors of CbE. Under exposure to organophosphorous pesticides, survival of Daphnia juveniles was impaired at AChE inhibition levels higher than 50% whereas under exposure to the carbamate carbofuran low levels of AChE inhibition affected mortality. Inhibition of CbE by 80-90% increased toxicity to organophosphorous and carbamate pesticides by up to two- and four-fold, respectively. Our results suggest that both AChE and CbE enzymes are involved in determining toxicity of Daphnia to the studied chemicals and that AChE inhibition levels higher than 50% can be considered of environmental concern to Daphnia species. PMID:15036868

  18. 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.

  19. Adsorption Kinetics of Carbamate Pesticide in Rice Field Soil

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    Soontree Khuntong

    2010-07-01

    Full Text Available Ultrasonic extraction (75.55% with petroleum ether:acetone (1:1, v/v was employed for extraction of carbofuran in rice field soil. The amounts of carbofuran were determined by reverse phase HPLC. The analytical method provided high precision and accuracy with the relative error of 0.47%. The percentage of recoveries varied from 84% to 77% in the con¬centration ranges of 10–40 mg/L of spiked soil samples. The carbofuran residues in the rice field soil significantly decreased year by year because of pesticide properties, soil properties and degradation conditions. A high amount of residues was found in the plots that contained high organic contents. The adsorption of carbofuran in soil reached equilibrium within 23 h. The percentage of adsorption varied from almost 30% to 80% depending on concentrations of carbofuran. The adsorption of carbofuran agreed with Freundlich isotherms; q = 7.07 x 10-5Cf2.5092; with the correlation coefficient of 0.9281. Organic carbon coefficient, Koc, was 1.91 x 10-3 mg/L calculated from Kd, and half-life (8.9 d of adsorbed carbofuran. The GUS index (6.37 calculated from Koc presented a high lixiviation potential. The positive ΔG indicated the non-spontaneous reaction. Carbofuran rapidly desorbed from soil at the desorption rate of 0.0228 mg/kg soil d. Kinetic studies provided the first order reaction with the reaction rate of 0.0779 mg/d and half-life of 8.9 days.

  20. From immunotoxicity to carcinogenicity: the effects of carbamate pesticides on the immune system.

    Science.gov (United States)

    Dhouib, Ines; Jallouli, Manel; Annabi, Alya; Marzouki, Soumaya; Gharbi, Najoua; Elfazaa, Saloua; Lasram, Mohamed Montassar

    2016-05-01

    The immune system can be the target of many chemicals, with potentially severe adverse effects on the host's health. In the literature, carbamate (CM) pesticides have been implicated in the increasing prevalence of diseases associated with alterations of the immune response, such as hypersensitivity reactions, some autoimmune diseases and cancers. CMs may initiate, facilitate, or exacerbate pathological immune processes, resulting in immunotoxicity by induction of mutations in genes coding for immunoregulatory factors and modifying immune tolerance. In the present study, direct immunotoxicity, endocrine disruption and inhibition of esterases activities have been introduced as the main mechanisms of CMs-induced immune dysregulation. Moreover, the evidence on the relationship between CM pesticide exposure, dysregulation of the immune system and predisposition to different types of cancers, allergies, autoimmune and infectious diseases is criticized. In addition, in this review, we will discuss the relationship between immunotoxicity and cancer, and the advances made toward understanding the basis of cancer immune evasion. PMID:26988364

  1. Biochemical and Histopathological Changes in The Rat Following Exposure to a Carbamate Pesticide

    International Nuclear Information System (INIS)

    Oxamyl is a carbamate pesticide with an oral LD50 of 5.4 mg/kg for male rats. To evaluate the subacute toxicity of the compound, two groups of male rats were dosed with 0.9 and 2.5 mg/kg/day of the pesticide, for 16 days. Toxicological evaluation included clinical chemistry and histopathological changes at the end of the study. The compound significantly altered serum alkaline phosphatase, uric acid, cholesterol, creatinine, blood urea nitrogen (BUN), serum glutamic pyruvic transaminase (SGPT and testosterone. Liver, Kidney and testicular histology revealed mild degenerative changes in the liver with the lower dose and significant degenerative changes with increased lymphocytic infiltrate with the higher dose and mild degenerative changes of the kidney with the higher dose only. Examination of the testis revealed no pathological changes at both dose levels

  2. Biodegradation of carbamate pesticides by natural river biofilms in different seasons and their effects on biofilm community structure.

    Science.gov (United States)

    Tien, Chien-Jung; Lin, Mon-Chu; Chiu, Wan-Hsin; Chen, Colin S

    2013-08-01

    This study investigated the ability of natural river biofilms from different seasons to degrade the carbamate pesticides methomyl, carbaryl and carbofuran in single and multiple pesticide systems, and the effects of these pesticides on algal and bacterial communities within biofilms. Spring biofilms had the lowest biomass of algae and bacteria but showed the highest methomyl degradation (>99%) and dissipation rates, suggesting that they might contain microorganisms with high methomyl degradation abilities. Degradation of carbofuran (54.1-59.5%) by biofilms in four seasons was similar, but low degradation of carbaryl (0-27.5%) was observed. The coexistence of other pesticides was found to cause certain effects on pesticide degradation and primarily resulted in lower diversity of diatoms and bacteria than when using a single pesticide. The tolerant diatoms and bacteria potentially having the ability to degrade test pesticides were identified. River biofilms could be suitable biomaterials or used to isolate degraders for bioremediating pesticide-contaminated water.

  3. Benchmark Dose Analysis from Multiple Datasets: The Cumulative Risk Assessment for the N-Methyl Carbamate Pesticides

    Science.gov (United States)

    The US EPA’s N-Methyl Carbamate (NMC) Cumulative Risk assessment was based on the effect on acetylcholine esterase (AChE) activity of exposure to 10 NMC pesticides through dietary, drinking water, and residential exposures, assuming the effects of joint exposure to NMCs is dose-...

  4. An evaluation of liquid chromatography/mass spectrometry with atmospheric pressure chemical ionization for the rapid and simultaneous measurement of carbamate pesticides and organophorus pesticides

    International Nuclear Information System (INIS)

    Liquid chromatography/mass spectrometry with an atmospheric pressure chemical ionization interface (LC/APCI/MS) is evaluated for the simultaneous determination of carbamate pesticides and organophosphorus pesticides in a single chromatographic analysis. APCI mass spectra of those compounds were obtained to study their ionization characteristics. APCI provided abundant ions such as protonated molecules and characteristic fragment ions for carbamate pesticides and organophosphorus pesticides. To evaluate the feasibility of the LC/APCI/MS for a routine quantitative analysis, the linearity and repeatability of LC/APCI/MS were examined by measuring standard solution mixtures of five carbamate pesticides and four organophosphorus pesticides over the range of 1 to 100 μg/mL. The peak areas in chromatograms of characteristic ions for those compounds showed less than 3% of variation from run to tun. The standard calibration curves for the nine pesticides show good linearity in the concentration range. The detection limits of the LC/APCI/MS system for those compounds range from 0.006 to 0.2 ng

  5. Determination of Carbamate and Organophosphorus Pesticides in Vegetable Samples and the Efficiency of Gamma-Radiation in Their Removal

    Directory of Open Access Journals (Sweden)

    Muhammed Alamgir Zaman Chowdhury

    2014-01-01

    Full Text Available In the present study, the residual pesticide levels were determined in eggplants (Solanum melongena (n=16, purchased from four different markets in Dhaka, Bangladesh. The carbamate and organophosphorus pesticide residual levels were determined by high performance liquid chromatography (HPLC, and the efficiency of gamma radiation on pesticide removal in three different types of vegetables was also studied. Many (50% of the samples contained pesticides, and three samples had residual levels above the maximum residue levels determined by the World Health Organisation. Three carbamates (carbaryl, carbofuran, and pirimicarb and six organophosphates (phenthoate, diazinon, parathion, dimethoate, phosphamidon, and pirimiphos-methyl were detected in eggplant samples; the highest carbofuran level detected was 1.86 mg/kg, while phenthoate was detected at 0.311 mg/kg. Gamma radiation decreased pesticide levels proportionately with increasing radiation doses. Diazinon, chlorpyrifos, and phosphamidon were reduced by 40–48%, 35–43%, and 30–45%, respectively, when a radiation strength of 0.5 kGy was utilized. However, when the radiation dose was increased to 1.0 kGy, the levels of the pesticides were reduced to 85–90%, 80–91%, and 90–95%, respectively. In summary, our study revealed that pesticide residues are present at high amounts in vegetable samples and that gamma radiation at 1.0 kGy can remove 80–95% of some pesticides.

  6. Solid phase extraction and determination of carbamate pesticides in water samples by reverse-phase HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Moreno-Tovar, J.; Santos-Delgado, M.J. [Departamento de Quimica Analitica, Facultad de ciencias Quimicas, Universidad Complutense de Madrid (Spain)

    1995-12-31

    Solid phase extraction. SPE. using C{sub 1}8 bonded silica cartridges for trace amounts determination of carbaryl, propoxur, thiram, propham and methiocarb in water samples was studied and the breakthrough volume of the cartridges was established. The high enrichment factor and large injection volume admissible in the isocratic reverse-phase HPLC system allows pesticides determination with UV detection at 22o nm even at a concentration lower than 0.05 mug/L. Purified tap natural and underground water samples were spiked with carbamate pesticides in the concentration range 0.16-16.0 mug/L. Large volumes of samples (up to 2L) were passed through available C{sub 1}8, cartridges and eluted with acetonitrile. The preconcentrated samples were analyzed by HPLC using a Spherisorb ODS column with a 42.58 acetonitrile-water mobile phase. From replicate samples, recovery for the pesticides ranged from 79.0 to 103.7% except for thiran which is not retained. Tehe relative standard deviation (n=4 at 0.16 to 1.61 mug/L concetration level) range from 1.1 to 6.8%. (Author) 14 refs.

  7. Immobilization of acetylcholinesterase via biocompatible interface of silk fibroin for detection of organophosphate and carbamate pesticides

    Science.gov (United States)

    Xue, Rui; Kang, Tian-Fang; Lu, Li-Ping; Cheng, Shui-Yuan

    2012-06-01

    An amperometric biosensor for the detection of organophosphate and carbamate pesticides was developed based on the immobilization of acetylcholinesterase (AChE) on regenerated silk fibroin (SF) matrix by non-covalent adsorption. SF and AChE were coated sequentially on the surface of the glassy carbon electrode (GCE) which was modified with multiwall carbon nanotube (MWNTs). The obtained biosensor was denoted as AChE-SF/MWNTs/GCE. The atomic force microscopy images showed that the SF matrix provided a more homogeneous interface for the AChE immobilization. The aggregation of immobilizing AChE was therefore avoided. The cyclic voltammogram of thiocholine at this biosensor exhibited a well defined oxidation peak at 0.667 V (vs. SCE). The inhibition rate of methyl parathion to the immobilized AChE was proportional to the logarithm of the concentration of methyl parathion over the range of the concentration of methyl parathion from 3.5 × 10-6 to 2.0 × 10-3 M with a detection limit of 5.0 × 10-7 M. Similarly, the linearly response range of carbaryl was from 1.0 × 10-7 to 3.0 × 10-5 M with a detection limit of 6.0 × 10-8 M. The experimental results indicate that AChE not only can be immobilized steadily on the SF matrix, but also the bioactivity of immobilizing AChE can be preserved effectively.

  8. Comparative voltammetric study and determination of carbamate pesticide residues in soil at carbon nanotubes paste electrodes

    Directory of Open Access Journals (Sweden)

    THOMMANDRU RAVEENDRANATH BAB

    2014-02-01

    Full Text Available In this investigation, the persistence of carbamate pesticides in soil samples was investigated. A simple and selective differential pulse adsorptive stripping voltammetry was selected for this investigation. Carbon nanotubes paste electrodes were used as working electrodes for differential pulse adsorptive stripping voltammetry and cyclic voltammetry. A symmetric study of the various operational parameters that affect the stripping response was carried out by differential pulse voltammetry. Peak currents were linear over the concentration range of 10-5 to 10-10 M with an accumulation potential of -0.6 V and a 70 s accumulation time with lower detection limits of 1.09 x 10-7 M, 1.07 × 10-7M, 1.09×10-7 M for chlorphropham, thiodicarb, aldicarb. The relative standard deviation (n=10 and correlation coefficient values were 1.15 %, 0.988; 1.13 %, 0.978; and 1.14 %, 0.987, respectively. Universal buffer with pH range 2.0 - 6.0 was used as sup­porting electrolyte. The solutions with uniform concentration (10-5 M were used in all deter­minations. Calculations were made by standard addition method.

  9. Immobilization of acetylcholinesterase via biocompatible interface of silk fibroin for detection of organophosphate and carbamate pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Xue Rui [College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Kang Tianfang, E-mail: kangtf@yahoo.cn [College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Lu Liping; Cheng Shuiyuan [College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China)

    2012-06-01

    An amperometric biosensor for the detection of organophosphate and carbamate pesticides was developed based on the immobilization of acetylcholinesterase (AChE) on regenerated silk fibroin (SF) matrix by non-covalent adsorption. SF and AChE were coated sequentially on the surface of the glassy carbon electrode (GCE) which was modified with multiwall carbon nanotube (MWNTs). The obtained biosensor was denoted as AChE-SF/MWNTs/GCE. The atomic force microscopy images showed that the SF matrix provided a more homogeneous interface for the AChE immobilization. The aggregation of immobilizing AChE was therefore avoided. The cyclic voltammogram of thiocholine at this biosensor exhibited a well defined oxidation peak at 0.667 V (vs. SCE). The inhibition rate of methyl parathion to the immobilized AChE was proportional to the logarithm of the concentration of methyl parathion over the range of the concentration of methyl parathion from 3.5 Multiplication-Sign 10{sup -6} to 2.0 Multiplication-Sign 10{sup -3} M with a detection limit of 5.0 Multiplication-Sign 10{sup -7} M. Similarly, the linearly response range of carbaryl was from 1.0 Multiplication-Sign 10{sup -7} to 3.0 Multiplication-Sign 10{sup -5} M with a detection limit of 6.0 Multiplication-Sign 10{sup -8} M. The experimental results indicate that AChE not only can be immobilized steadily on the SF matrix, but also the bioactivity of immobilizing AChE can be preserved effectively.

  10. Rapid and sensitive suspension array for multiplex detection of organophosphorus pesticides and carbamate pesticides based on silica-hydrogel hybrid microbeads.

    Science.gov (United States)

    Wang, Xuan; Mu, Zhongde; Shangguan, Fengqi; Liu, Ran; Pu, Yuepu; Yin, Lihong

    2014-05-30

    A technique for multiplex detection of organophosphorus pesticides and carbamate pesticides has been developed using a suspension array based on silica-hydrogel hybrid microbeads (SHHMs). The main advantage of SHHMs, which consist of both silica and hydrogel materials, is that they not only could be distinguished by their characteristic reflection peak originating from the stop-band of the photonic crystal but also have low non-specific adsorption of proteins. Using fluorescent immunoassay, the LODs for fenitrothion, chlorpyrifos-methyl, fenthion, carbaryl and metolcarb were measured to be 0.02ng/mL, 0.012ng/mL, 0.04ng/mL, 0.05ng/mL and 0.1ng/mL, respectively, all of which are much lower than the maximum residue limits, as reported in the European Union pesticides database. All the determination coefficients for these five pesticides were greater than 0.99, demonstrating excellent correlations. The suspension array was specific and had no significant cross-reactivity with other chemicals. The results for the detection of pesticide residues collected from agricultural samples using this method agree well with those from liquid chromatography-tandem mass spectrometry. Our results showed that this simple method is suitable for simultaneous detection of these five pesticides residues in fruits and vegetables.

  11. Evaluation of exposure to organophosphate, carbamate, phenoxy acid, and chlorophenol pesticides in pregnant women from 10 Caribbean countries.

    Science.gov (United States)

    Forde, Martin S; Robertson, Lyndon; Laouan Sidi, Elhadji A; Côté, Suzanne; Gaudreau, Eric; Drescher, Olivia; Ayotte, Pierre

    2015-09-01

    Pesticides are commonly used in tropical regions such as the Caribbean for both household and agricultural purposes. Of particular concern is exposure during pregnancy, as these compounds can cross the placental barrier and interfere with fetal development. The objective of this study was to evaluate exposure of pregnant women residing in 10 Caribbean countries to the following commonly used classes of pesticides in the Caribbean: organophosphates (OPs), carbamates, phenoxy acids, and chlorophenols. Out of 438 urine samples collected, 15 samples were randomly selected from each Caribbean country giving a total of 150 samples. Samples were analyzed for the following metabolites: six OP dialkylphosphate metabolites [dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP) and diethyldithiophosphate (DEDTP)]; two carbamate metabolites [2-isopropoxyphenol (2-IPP) and carbofuranphenol]; one phenoxy acid 2,4-dichlorophenoxyacetic acid (2,4-D); and five chlorophenols [2,4-dichlorophenol (DCP), 2,5-dichlorophenol (2,5-DCP), 2,4,5-trichlorophenol (TCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP)]. OP metabolites were consistently detected in ≥60% of the samples from Antigua and Barbuda, Bermuda, and Jamaica. Of the carbamate metabolites, 2-IPP was detected in seven of the 10 Caribbean countries with a detection frequency around 30%, whereas carbofuranphenol was detected in only one sample. The detection frequency for the phenoxy acid 2,4-D ranged from 20% in Grenada to a maximum of 67% in Belize. Evidence of exposure to chlorophenol pesticides was also established with 2,4-DCP by geometric means ranging from 0.52 μg L(-1) in St Lucia to a maximum of 1.68 μg L(-1) in Bermuda. Several extreme concentrations of 2,5-DCP were detected in four Caribbean countries-Belize (1100 μg L(-1)), Bermuda (870 μg L(-1)), Jamaica (1300 μg L(-1)), and St Kitts and Nevis (1400 μg L(-1

  12. Rapid and sensitive suspension array for multiplex detection of organophosphorus pesticides and carbamate pesticides based on silica–hydrogel hybrid microbeads

    International Nuclear Information System (INIS)

    Highlights: • Silica–hydrogel hybrid microbeads were used to develop suspension array. • The results in detecting pesticides agree well with those from LC–MS/MS. • The method showed the good capability for multiplex analysis of pesticides residues. - Abstract: A technique for multiplex detection of organophosphorus pesticides and carbamate pesticides has been developed using a suspension array based on silica–hydrogel hybrid microbeads (SHHMs). The main advantage of SHHMs, which consist of both silica and hydrogel materials, is that they not only could be distinguished by their characteristic reflection peak originating from the stop-band of the photonic crystal but also have low non-specific adsorption of proteins. Using fluorescent immunoassay, the LODs for fenitrothion, chlorpyrifos-methyl, fenthion, carbaryl and metolcarb were measured to be 0.02 ng/mL, 0.012 ng/mL, 0.04 ng/mL, 0.05 ng/mL and 0.1 ng/mL, respectively, all of which are much lower than the maximum residue limits, as reported in the European Union pesticides database. All the determination coefficients for these five pesticides were greater than 0.99, demonstrating excellent correlations. The suspension array was specific and had no significant cross-reactivity with other chemicals. The results for the detection of pesticide residues collected from agricultural samples using this method agree well with those from liquid chromatography–tandem mass spectrometry. Our results showed that this simple method is suitable for simultaneous detection of these five pesticides residues in fruits and vegetables

  13. Rapid and sensitive suspension array for multiplex detection of organophosphorus pesticides and carbamate pesticides based on silica–hydrogel hybrid microbeads

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xuan [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China); Mu, Zhongde; Shangguan, Fengqi [State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, Jiangsu (China); Liu, Ran; Pu, Yuepu [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China); Yin, Lihong, E-mail: lhyin@seu.edu.cn [Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, Jiangsu (China)

    2014-05-01

    Highlights: • Silica–hydrogel hybrid microbeads were used to develop suspension array. • The results in detecting pesticides agree well with those from LC–MS/MS. • The method showed the good capability for multiplex analysis of pesticides residues. - Abstract: A technique for multiplex detection of organophosphorus pesticides and carbamate pesticides has been developed using a suspension array based on silica–hydrogel hybrid microbeads (SHHMs). The main advantage of SHHMs, which consist of both silica and hydrogel materials, is that they not only could be distinguished by their characteristic reflection peak originating from the stop-band of the photonic crystal but also have low non-specific adsorption of proteins. Using fluorescent immunoassay, the LODs for fenitrothion, chlorpyrifos-methyl, fenthion, carbaryl and metolcarb were measured to be 0.02 ng/mL, 0.012 ng/mL, 0.04 ng/mL, 0.05 ng/mL and 0.1 ng/mL, respectively, all of which are much lower than the maximum residue limits, as reported in the European Union pesticides database. All the determination coefficients for these five pesticides were greater than 0.99, demonstrating excellent correlations. The suspension array was specific and had no significant cross-reactivity with other chemicals. The results for the detection of pesticide residues collected from agricultural samples using this method agree well with those from liquid chromatography–tandem mass spectrometry. Our results showed that this simple method is suitable for simultaneous detection of these five pesticides residues in fruits and vegetables.

  14. Monitoring of N-methyl carbamate pesticide residues in water using hollow fibre supported liquid membrane and solid phase extraction

    Science.gov (United States)

    Msagati, Titus A. M.; Mamba, Bhekie B.

    The aim of this work was to develop a method for the determination of N-methyl carbamates in water involving hollow fibre supported liquid membrane (HFSLM) and solid phase extraction (SPE) as sample preparation methods. Four N-methyl carbamate pesticides, aldicarb, carbaryl, carbofuran and methiocarb sulfoxide, were simultaneously extracted and analysed by a liquid chromatograph with a diode array detector (LC-UV/DAD) and a liquid chromatograph coupled to a ion trap quadrupole mass spectrometer (LC-ESI-MS). The high performance liquid chromatography (HPLC) separation of carabamate extracts was performed on a C18 column with water-acetonitrile as the mobile phase. The mass spectrometry analyses were carried out in the positive mode, operating under both the selected ion monitoring (SIM) and full scan modes. The solid phase recoveries of the extracts ranged between 8% and 98%, with aldicarb having the highest recoveries, followed by carbaryl, carbofuran and methiocarb had the lowest recovery. The HFSLM recovery ranged between 8% and 58% and the order of recovery was similar to the SPE trend. Factors controlling the efficiency of the HFSLM extraction such as sample pH, stripping phase pH, enrichment time, stirring speed as well as organic solvent used for entrapment of analytes, were optimised to achieve the highest enrichment factors.

  15. Poisoning of raptors with organophosphorus and carbamate pesticides with emphasis on Canada, U.S. and U.K.

    Science.gov (United States)

    Mineau, P.; Fletcher, M.R.; Glaser, L.C.; Thomas, N.J.; Brassard, C.; Wilson, L.K.; Elliott, J.E.; Lyon, L.A.; Henny, C.J.; Bollinger, T.; Porter, S.L.

    1999-01-01

    We reviewed cases of raptor mortality resulting from cholinesterase-inhibiting pesticides. We compiled records from the U.S., U.K. and Canada for the period 1985-95 (520 incidents) and surveyed the relevant literature to identify the main routes of exposure and those products that led to the greatest number of poisoning cases. A high proportion of cases in the U.K. resulted from abusive uses of pesticides (willful poisoning). The proportion was smaller in North America where problems with labeled uses of pesticides were as frequent as abuse cases. Poisoning resulting from labeled use was possible with a large number of granular pesticides and some seed treatments through secondary poisoning or through the ingestion of contaminated invertebrates, notably earthworms. With the more toxic products, residue levels in freshly-sprayed insects were high enough to cause mortality. The use of organophosphorus products as avicides and for the topical treatment of livestock appeared to be common routes of intoxication. The use of insecticides in dormant oils also gave rise to exposure that can be lethal or which can debilitate birds and increase their vulnerability. A few pesticides of high toxicity were responsible for the bulk of poisoning cases. Based on limited information, raptors appeared to be more sensitive than other bird species to organophosphorus and carbamate pesticides. Some of the more significant risk factors that resulted in raptor poisonings were: insectivory and vermivory; opportunistic taking of debilitated prey; scavenging, especially if the gastrointestinal tracts are consumed; presence in agricultural areas; perceived status as pest species; and flocking or other gregarious behavior at some part of their life cycle. Lethal or sublethal poisoning should always be considered in the diagnosis of dead or debilitated raptors even when another diagnosis (e.g., electrocution, car or building strike) is apparent. Many cases of poisoning are not currently

  16. Fluorescence biosensing strategy based on mercury ion-mediated DNA conformational switch and nicking enzyme-assisted cycling amplification for highly sensitive detection of carbamate pesticide.

    Science.gov (United States)

    Wang, Xiuzhong; Hou, Ting; Dong, Shanshan; Liu, Xiaojuan; Li, Feng

    2016-03-15

    Pesticides are of great importance in agricultural and biological fields, but pesticide residues may harm the environment and human health. A highly sensitive fluorescent biosensor for the detection of carbamate pesticide has been developed based on acetylcholinesterase (AChE)-catalyzed hydrolysis product triggered Hg(2+) release coupled with subsequent nicking enzyme-induced cleavage of a duplex DNA for cycling amplification. In this protocol, two DNA probes, an unmodified single-stranded helper DNA probe 1 (HP1) and a quencher-fluorophore probe (QFP) are ingeniously designed. HP1 can be folded into hairpin configuration through T-Hg(2+)-T base pair formation. QFP, labeled with FAM and BHQ1 at its two terminals, contains the recognition sequence and the cleavage site of the nicking enzyme. In the presence of carbamate pesticide, the activity of AChE is inhibited, and the amount of the product containing the thiol group generated by the hydrolysis reaction of acetylthiocholine chloride (ACh) decreases, resulting in the release of a low concentration of Hg(2+). The number of HP1 that can be selectively unfolded would be reduced and the subsequent nicking enzyme-assisted cleavage processes would be affected, resulting in decreased fluorescence signals. The fluorescence intensity further decreases with the increase of the pesticide concentration. Therefore, the pesticide content can be easily obtained by monitoring the fluorescence signal change, which is inversely proportional to the logarithm of the pesticide concentration. The detection limit of aldicarb, the model analyte, is 3.3 μgL(-1), which is much lower than the Chinese National Standards or those previously reported. The as-proposed method has also been applied to detect carbamate pesticide residues in fresh ginger and artificial lake water samples with satisfactory results, which demonstrates that the method has great potential for practical application in biological or food safety field.

  17. A simple electrochemical biosensor based on AuNPs/MPS/Au electrode sensing layer for monitoring carbamate pesticides in real samples.

    Science.gov (United States)

    Song, Yonghai; Chen, Jingyi; Sun, Min; Gong, Coucong; Shen, Yuan; Song, Yonggui; Wang, Li

    2016-03-01

    A simple electrochemical biosensor for quantitative determination of carbamate pesticide was developed based on a sensing interface of citrate-capped gold nanoparticles (AuNPs)/(3-mercaptopropyl)-trimethoxysilane (MPS)/gold electrode (Au). The biosensor was fabricated by firstly assembling three-dimensional (3D) MPS networks on Au electrode and subsequently assembling citrate-capped AuNPs on 3D MPS network via AuS bond. The interface of AuNPs/MPS/Au was negatively charged originating from the citrate coated on AuNPs that would repulse the negatively charged ferricyanide ([Fe(CN)6](3-/4-)) to produce a negative response. In the presence of acetylcholinesterase (AChE) and acetylthiocholine (ATCl), the AChE catalyzes the hydrolysis of ATCl into positively charged thiocholine which would replace the citrate on AuNPs through the strong AuS bond and convert the negative charged surface to be positively charged. The resulted positively charged AuNPs/MPS/Au then attracted the [Fe(CN)6](3-/4-) to produce a positive response. Based on the inhibition of carbamate pesticides on the activity of AChE, the pesticide could be quantitatively determined at a very low potential. The linear range was from 0.003 to 2.00 μM. The sensing platform was also proved to be suitable for carbamate pesticides detection in practical sample.

  18. 氨基甲酸酯类农药的微色谱快速检测法%Rapid Determination of Carbamate Pesticides by Micro-chromatography

    Institute of Scientific and Technical Information of China (English)

    卫海燕; 邵华

    2011-01-01

    [ Objective] To rapidly detect the carbamate pesticides by preparing a new instrument of micro-column detector with capillary effect. [ Methods ] Based on the principle of thin-layer chromatography, fixing the sorbent in the thin heating wire, using microcolumn detector to prepare a new instrument of micro-column detector, the carbamate pesticides was rapidly detected and analyzed qualitatively and quantitatively. [ Results ] The method can make qualitative and quantitative analysis of carbamate pesticides, and the minimum detection limit was 50 μg. [ Conclusion ] The method is simple, efficient , reproducible, with less reagent consumption,can be used to detect bulk carbamate pesticides samples and it is a new method for rapid pesticide poisoning filtering.%目的 利用毛细管效应建立制备微色谱柱检测器以快速检测氨基甲酸酯类农药.方法 在薄层色谱原理的基础上,通过将吸着剂固定于细加热丝上,利用毛细管效应制备微色谱柱检测器,对氨基甲酸酯类农药作出快速的定性分析.结果 该方法 可以对氨基甲酸酯类农药作出快速的定性分析,且最低检出量可达到50 μg.结论 该法操作简便,高效,重现性好,且试剂用量少,是批量氨基甲酸酯类农药样品定性检测和突发农药中毒事件现场快速筛选的一种新方法 .

  19. Studies on the Purification and Characterization of Soybean Esterase,and Its Sensitivity to Organophosphate and Carbamate Pesticides

    Institute of Scientific and Technical Information of China (English)

    LI Jian-ke; ZHOU Yan-li; WEN Yan-xia; WANG Jian-hua; HU Qiu-hui

    2009-01-01

    Soybean esterase,a cholinesterase-like enzyme,was purified by differential centrifugation firstly,then,ammonium sulfate precipitation,dialysis,and finally,DEAE-cellulose-32 ion-exchange chromatography after extracting it from soybean seeds with phosphate buffer(0.3 mol L-1,pH 7.0).The extract recovery rate of the purified enzyme was 8.18% and purification fold was 91.58.The soybean esterase appeared as two bands on the denaturing SDS-PAGE with molecular weights of 24 and 37.2 kDa,respectively,which proved that it is a dimer protein consisting of two subunits.The result of nondenaturing PAGE revealed that the soybean esterase is a single band with cholinesterase-like activity using α-naphthyl acetate as the substrate and fast blue B salt as coloring agent.The esterase showed very high sensitivity to 18 kinds of organophosphate pesticides and 6 kinds of carbamate pesticides with the lowest detective limits of 0.03125-0.0625 and 0.03 125-0.25 mg kg-1,respectively,and can meet the demands of MRL specified by the most countries.

  20. Ionic liquid polymer functionalized carbon nanotubes-doped poly(3,4-ethylenedioxythiophene) for highly-efficient solid-phase microextraction of carbamate pesticides.

    Science.gov (United States)

    Wu, Mian; Wang, Liying; Zeng, Baizhao; Zhao, Faqiong

    2016-04-29

    A poly(3,4-ethylenedioxythiophene)-ionic liquid polymer functionalized multiwalled carbon nanotubes (PEDOT-PIL/MWCNTs) composite solid-phase microextraction (SPME) coating was fabricated by electrodeposition. After being dipped in Nafion solution, a Nafion-modified coating was obtained. The outer layer Nafion played a crucial role in enhancing the durability and stability of the coating, thus it was robust enough for replicated extraction for at least 150 times without decrease of extraction performance. The Nafion-modified coating exhibited much higher sensitivity than commercial coatings for the direct extraction of carbamate pesticides in aqueous solutions, due to its strong hydrophobic effect and π-π affinity based enrichment. When it was used for the determination of carbamate pesticides in combination with gas chromatography-flame ionization detection, good linearity (correlation coefficients higher than 0.9981), low limits of detection (15.2-27.2 ng/L) and satisfactory precision (relative standard deviation <8.2%, n=5) were achieved. The developed method was applied to the analysis of four carbamate pesticides in apple and lettuce samples, and acceptable recoveries (i.e. 87.5-106.5%) were obtained for the standard addition. PMID:27036210

  1. Organophosphorus and Carbamate Pesticide Residues Detected in Water Samples Collected from Paddy and Vegetable Fields of the Savar and Dhamrai Upazilas in Bangladesh

    Directory of Open Access Journals (Sweden)

    Nurul Karim

    2012-09-01

    Full Text Available Several types of organophosphorous and carbamate pesticides have been used extensively by the farmers in Bangladesh during the last few decades. Twenty seven water samples collected from both paddy and vegetable fields in the Savar and Dhamrai Upazilas in Bangladesh were analyzed to determine the occurrence and distribution of organo-phosphorus (chlorpyrifos, malathion and diazinon and carbamate (carbaryl and carbofuran pesticide residues. A high performance liquid chromatograph instrument equipped with a photodiode array detector was used to determine the concentrations of these pesticide residues. Diazinon and carbofuran were detected in water samples collected from Savar Upazila at 0.9 μg/L and 198.7 μg/L, respectively. Malathion was also detected in a single water sample at 105.2 μg/L from Dhamrai Upazila. Carbaryl was the most common pesticide detected in Dhamrai Upazila at 14.1 and 18.1 μg/L, while another water sample from Dhamrai Upazila was contaminated with carbofuran at 105.2 μg/L. Chlorpyrifos was not detected in any sample. Overall, the pesticide residues detected were well above the maximum acceptable levels of total and individual pesticide contamination, at 0.5 and 0.1 μg/L, respectively, in water samples recommended by the European Economic Community (Directive 98/83/EC. The presence of these pesticide residues may be attributed by their intense use by the farmers living in these areas. Proper handling of these pesticides should be ensured to avoid direct or indirect exposure to these pesticides.

  2. Age-related differences in neurotoxicity produced by organophosphorus and N-methyl carbamate pesticides

    Science.gov (United States)

    Potential pesticide effects in infants and toddlers have received much attention in the scientific literature and the public media, including the concern for increased response to acute or shortterm exposures. Age-related differences in the acute neurotoxicity of acetylcholinest...

  3. Poisoning of cats and dogs by the carbamate pesticides aldicarb and carbofuran.

    Science.gov (United States)

    de Siqueira, Adriana; Salvagni, Fernanda Auciello; Yoshida, Alberto Soiti; Gonçalves-Junior, Vagner; Calefi, Atilio Sersun; Fukushima, André Rinaldi; Spinosa, Helenice de Souza; Maiorka, Paulo César

    2015-10-01

    The intentional and accidental poisoning of animals and people is a threat to public health and safety worldwide. Necropsies and histopathological examinations of 26 cats and 10 dogs poisoned by the carbamates aldicarb and carbofuran, confirmed by thin layer chromatography (TLC) and high performance liquid chromatography with diode-array detector (HPLC-DAD) were analysed, with variable post mortem interval and conservation of the carcass. Biological matrices were collected for toxicological and histopathological analyses. High performance liquid chromatography with diode-array detector (HPLC-DAD) was utilized to detect aldicarb and its metabolites, aldicarb sulphoxide and aldicarb sulphone, and carbofuran. The variable post mortem interval and the method of conservation of the carcass may be harmful to toxicological, necroscopic and histopathological analyses, that should be performed in order to provide reliable evidences to investigate possible poisoning of animals, which is cruel crime, and are usually linked to domestic or social conflict.

  4. SELECTIVE ISOLATION OF A GRAM NEGATIVE CARBAMATE PESTICIDE DEGRADING BACTERIUM FROM BRINJAL CULTIVATED SOIL

    Directory of Open Access Journals (Sweden)

    Dilara Islam Sharif

    2013-01-01

    Full Text Available A bacterial species having the ability to grow in the presence of carbosulfan pesticide “Marshall” was isolated from Solanum melongena (brinjal cultivated soil in Khulna region, Bangladeh, having a history of pesticide usage. The strain was morphologically and biochemically identified to belong to the genera Pseudomonas. A comparative study of growth of this strain with other isolated bacteria showed its ability to grow in the presence of different concentrations of Marshall. The susceptibility of the stain to Marshall was also assessed through disk diffusion assay which showed the strain to be resistant at concentrations of Marshal commonly used under field conditions. The selected strain also showed its capability to degrade Marshall through observed characteristics on sublimated agar plates. The biodegradation capability of the strain isolated in this study can be valuable for further study towards bioremediation of pesticide contaminated soils.

  5. Multi photon ionization mass spectrometry of carbamate pesticides, herbicides and fungicides

    International Nuclear Information System (INIS)

    Pesticides and herbicides are useful for a wide range of applications today. The determination of these substances either in the pure form or in complex matrices is of high analytical interest. Especially since these substances can by found in every day products. The combination of multi photon ionization (MUPI) and time of flight laser mass spectrometry may be a powerful tool for achieving fast well interpretable mass spectra for analytical purposes. In this paper we will discuss the mass spectra of several pesticides and herbicides accessed by MUPI-time-of-flight mass spectrometry. The influence of the laser pulse duration on the mass spectra are discussed

  6. The Stepwise Behavioral Responses: Behavioral Adjustment of the Chinese Rare Minnow (Gobiocypris rarus in the Exposure of Carbamate Pesticides

    Directory of Open Access Journals (Sweden)

    Zongming Ren

    2013-01-01

    Full Text Available In order to illustrate the behavioral regulation in environmental stress, the behavioral responses of the Chinese rare minnow (Gobiocypris rarus to arprocarb, carbofuran, and oxamyl were analyzed with an online monitoring system. The Self-Organizing Map (SOM was used to define the patterns of the behavioral data obtained from treatments at concentrations of 0.1 toxic unit (TU, 1 TU, 2 TU, 5 TU, 10 TU, and 20 TU and a control. In certain cases, differences among the carbamate pesticides (CPs tested were observed. The profiles of behavioral strength (BS in SOM varied according to the concentration used. The time of the first significant decrease of the BS varied inversely with the CP concentrations. The results suggested that the behavioral regulation in the stepwise behavioral responses (SBR was evident. The primary movement behaviors shown by the SBR model included no effect, stimulation, acclimation, adjustment (readjustment, and toxic effect, especially at the lower concentrations. However, higher stress (10 TU and 20 TU might limit the function of the behavioral adjustment produced by the intrinsic response mechanisms. It was concluded that SBR, which were affected by both the concentration and the exposure time, could be used as a suitable indicator in the ecotoxicological risk assessment of CPs.

  7. Age-related differences in acetylcholinesterase inhibition produced by organophosphorus and N-methyl carbamate pesticides

    Science.gov (United States)

    Introduction The concern that infants and children may be more susceptible to the toxic effects of chemicals, including pesticides, has received much attention in the scientific literature and the public media. Greater toxicity may be evident as long-term adverse outcomes, e.g.,...

  8. Sequential injection kinetic spectrophotometric determination of quaternary mixtures of carbamate pesticides in water and fruit samples using artificial neural networks for multivariate calibration

    Science.gov (United States)

    Chu, Ning; Fan, Shihua

    2009-12-01

    A new analytical method was developed for the simultaneous kinetic spectrophotometric determination of a quaternary carbamate pesticide mixture consisting of carbofuran, propoxur, metolcarb and fenobucarb using sequential injection analysis (SIA). The procedure was based upon the different kinetic properties between the analytes reacted with reagent in flow system in the non-stopped-flow mode, in which their hydrolysis products coupled with diazotized p-nitroaniline in an alkaline medium to form the corresponding colored complexes. The absorbance data from SIA peak time profile were recorded at 510 nm and resolved by the use of back-propagation-artificial neural network (BP-ANN) algorithms for multivariate quantitative analysis. The experimental variables and main network parameters were optimized and each of the pesticides could be determined in the concentration range of 0.5-10.0 μg mL -1, at a sampling frequency of 18 h -1. The proposed method was compared to other spectrophotometric methods for simultaneous determination of mixtures of carbamate pesticides, and it was proved to be adequately reliable and was successfully applied to the simultaneous determination of the four pesticide residues in water and fruit samples, obtaining the satisfactory results based on recovery studies (84.7-116.0%).

  9. Surface display of recombinant Drosophila melanogaster acetylcholinesterase for detection of organic phosphorus and carbamate pesticides.

    Directory of Open Access Journals (Sweden)

    Jingquan Li

    Full Text Available Acetylcholinesterase (AChE is commonly used for the detection of organophosphate (OP and carbamate (CB insecticides. However, the cost of this commercially available enzyme is high, making high-throughput insecticide detection improbable. In this study we constructed a new AChE yeast expression system in Saccharomyces cerevisiae for the expression of a highly reactive recombinant AChE originating from Drosophila melanogaster (DmAChE. Specifically, the coding sequence of DmAChE was fused with the 3'-terminal half of an α-agglutinin anchor region, along with an antigen tag for the detection of the recombinant protein. The target sequence was cloned into the yeast expression vector pYes-DEST52, and the signal peptide sequence was replaced with a glucoamylase secretion region for induced expression. The resultant engineered vector was transformed into S. cerevisiae. DmAChE was expressed and displayed on the cell surface after galactose induction. Our results showed that the recombinant protein displayed activity comparable to the commercial enzyme. We also detected different types of OP and CB insecticides through enzyme inhibition assays, with the expressed DmAChE showing high sensitivity. These results show the construction of a new yeast expression system for DmAChE, which can subsequently be used for detecting OP and CB insecticides with reduced economic costs.

  10. [Determination of 51 carbamate pesticide residues in vegetables by liquid chromatography-tandem mass spectrometry based on optimization of QuEChERS sample preparation method].

    Science.gov (United States)

    Wang, Lianzhu; Zhou, Yu; Huang, Xiaoyan; Wang, Ruilong; Lin, Zixu; Chen, Yong; Wang, Dengfei; Lin, Dejuan; Xu, Dunming

    2013-12-01

    The raw extracts of six vegetables (tomato, green bean, shallot, broccoli, ginger and carrot) were analyzed using gas chromatography-mass spectrometry (GC-MS) in full scan mode combined with NIST library search to confirm main matrix compounds. The effects of cleanup and adsorption mechanisms of primary secondary amine (PSA) , octadecylsilane (C18) and PSA + C18 on co-extractives were studied by the weight of evaporation residue for extracts before and after cleanup. The suitability of the two versions of QuEChERS method for sample preparation was evaluated for the extraction of 51 carbamate pesticides in the six vegetables. One of the QuEChERS methods was the original un-buffered method published in 2003, and the other was AOAC Official Method 2007.01 using acetate buffer. As a result, the best effects were obtained from using the combination of C18 and PSA for extract cleanup in vegetables. The acetate-buffered version was suitable for the determination of all pesticides except dioxacarb. Un-buffered QuEChERS method gave satisfactory results for determining dioxacarb. Based on these results, the suitable QuEChERS sample preparation method and liquid chromatography-positive electrospray ionization-tandem mass spectrometry under the optimized conditions were applied to determine the 51 carbamate pesticide residues in six vegetables. The analytes were quantified by matrix-matched standard solution. The recoveries at three levels of 10, 20 and 100 microg/kg spiked in six vegetables ranged from 58.4% to 126% with the relative standard deviations of 3.3%-26%. The limits of quantification (LOQ, S/N > or = 10) were 0.2-10 microg/kg except that the LOQs of cartap and thiofanox were 50 microg/kg. The method is highly efficient, sensitive and suitable for monitoring the 51 carbamate pesticide residues in vegetables. PMID:24669707

  11. Determination of poorly fluorescent carbamate pesticides in water, bendiocarb and promecarb, using cyclodextrin nanocavities and related media

    Energy Technology Data Exchange (ETDEWEB)

    Pacioni, Natalia L. [Instituto de Investigaciones en Fisico Quimica de Cordoba (INFIQC), Departamento de Quimica Organica, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Ciudad Universitaria, 5000 Cordoba (Argentina); Veglia, Alicia V. [Instituto de Investigaciones en Fisico Quimica de Cordoba (INFIQC), Departamento de Quimica Organica, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Ciudad Universitaria, 5000 Cordoba (Argentina)]. E-mail: aveglia@mail.fcq.unc.edu.ar

    2007-01-30

    The effect of native cyclodextrins ({alpha}, {beta}, or {gamma}CD with six, seven and eight glucose units, respectively), hydroxypropyl-{beta}-cyclodextrin (HPCD), chitosan (CHT) and glucose in water solution or water with n-propylamine (PA) as co-solvent upon the UV-vis and fluorescence properties of poorly fluorescent N-methyl carbamates pesticides (C) as bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-ol methylcarbamate, BC) and promecarb (3-methyl-5-(1-methylethyl)phenol methylcarbame, PC) was examined. Fluorescent enhancement was found for both substrates with all CDs in water or PA-water except from PC with {alpha}CD. The addition of CHT increases the fluorescence of BC but decreases the fluorescence of PC, and glucose addition gives in both cases no spectral changes. Host-guest interaction was clearly determined by fluorescence enhancement with {beta}CD and HPCD with a 1:1 stoichiometry for the complexes (C:CD). The values obtained for the association constants (K {sub A}, M{sup -1}) were (6 {+-} 2) x 10{sup 2} and (2.3 {+-} 0.3) x 10{sup 2} for BC:{beta}CD and BC:HPCD complexes, respectively. For PC:{beta}CD and PC:HPCD the values of K {sub A} were (19 {+-} 2) x 10{sup 2} and (21 {+-} 2) x 10{sup 2}, respectively. The ratio of the fluorescence quantum yields for the bound and free substrates ({phi} {sup CCD}/{phi} {sup C}) was in the range 1.74-3.8. The limits of detection (L {sub D}, {mu}g mL{sup -1}) for the best conditions were (0.57 {+-} 0.02) for BC with HPCD and (0.091 {+-} 0.002) for PC with {beta}CD in water. Application to the analysis in pesticide spiked samples of tap water and fruit yields satisfactory apparent recoveries (84-114%), and for the extraction procedure in fruits and a commercial formulation, recoveries were of 81-98% and 104%, respectively. The method is rapid, simple, direct, sensitive and useful for pesticide analysis.

  12. Validation of analytical methods for ethyl carbamate in nine food matrices.

    Science.gov (United States)

    Ryu, Dayeon; Choi, Bogyoung; Kim, Nayoung; Koh, Eunmi

    2016-11-15

    Ethyl carbamate (EC) is formed through a reaction between ethanol and either cyanate or N-carbamyl compounds. This study aimed to develop and validate analytical methods for EC determination in nine food matrices: apple juice, soju, milk, corn oil, rice porridge, peanut butter, beef, flat fish, and sea mustard. Differences from AOAC procedure were use of d5-EC as internal standard, dilution of alcohol content, removal of lipophilic compounds by hexane, and removal of hydrophilic polysaccharides by gel-forming. Standard curves had a good linearity (R(2)>0.997) in all matrices tested. LOD and LOQ were in the range of 0.69-6.08μg/kg and 2.10-18.43μg/kg, respectively. Recovery rates ranged from 80.75 to 121.82% for intra-day and ranged from 78.84 to 116.98% for inter-day. The relative standard deviations (RSDs) were below 14%. These results indicate that the established methods can be applied to determine EC in a variety of foods. PMID:27283695

  13. Ionic liquid polymer functionalized carbon nanotubes-doped poly(3,4-ethylenedioxythiophene) for highly-efficient solid-phase microextraction of carbamate pesticides.

    Science.gov (United States)

    Wu, Mian; Wang, Liying; Zeng, Baizhao; Zhao, Faqiong

    2016-04-29

    A poly(3,4-ethylenedioxythiophene)-ionic liquid polymer functionalized multiwalled carbon nanotubes (PEDOT-PIL/MWCNTs) composite solid-phase microextraction (SPME) coating was fabricated by electrodeposition. After being dipped in Nafion solution, a Nafion-modified coating was obtained. The outer layer Nafion played a crucial role in enhancing the durability and stability of the coating, thus it was robust enough for replicated extraction for at least 150 times without decrease of extraction performance. The Nafion-modified coating exhibited much higher sensitivity than commercial coatings for the direct extraction of carbamate pesticides in aqueous solutions, due to its strong hydrophobic effect and π-π affinity based enrichment. When it was used for the determination of carbamate pesticides in combination with gas chromatography-flame ionization detection, good linearity (correlation coefficients higher than 0.9981), low limits of detection (15.2-27.2 ng/L) and satisfactory precision (relative standard deviation pesticides in apple and lettuce samples, and acceptable recoveries (i.e. 87.5-106.5%) were obtained for the standard addition.

  14. Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography

    Institute of Scientific and Technical Information of China (English)

    Zhi Mei Liu; Xiao Huan Zang; Wei Hua Liu; Chun Wang; Zhi Wang

    2009-01-01

    A novel method for the determination of five carbamate pesticides(metolcarb,carbofuran,carbaryl,isoprocard and diethofencard)in water samples was developed by dispersive liquid-liquid microextraction(DLLME)coupled with high performance liquid chromatography-diode array detector(HPLC-DAD).Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results.Under the optimum conditions for the method,the calibration curve was linear in the concentration range from 5 to I000 ng mL-1 for all the five carbamate pesticides,with the correlation coefficients(r2)varying from 0.9984 to 0.9994.Good enrichment factors were achieved ranging from 80 to 177-fold,depending on the compound.The limits of detection(LODs)(S/N = 3)were ranged from 0.1 to 0.5 ng mL-1.The method has been successfully applied to the analysis of the pesticide residues in environmental water samples.

  15. Carbon nanotubes-reinforced hollow fibre solid-phase microextraction coupled with high performance liquid chromatography for the determination of carbamate pesticides in apples.

    Science.gov (United States)

    Song, Xin-Yue; Shi, Yan-Ping; Chen, Juan

    2013-08-15

    An effective and sensitive method to determinate five carbamate pesticides in apples was developed by using carbon nanotubes-reinforced hollow fibre solid-phase microextraction (CNTs-HF-SPME) combined with high performance liquid chromatography-photodiode array detection (HPLC-DAD). The CNTs were dispersed in water via adding surfactant, and then were held in the pores of HF supported by capillary forces and sonification. The SPME device, which was wetted with 1-octanol, was placed in a stirred apple samples to extract target analytes. After extraction, analytes were desorbed and analyzed using HPLC-DAD. Under the optimized extraction conditions, the enrichment factors were achieved in the range from 49 to 308 with good inter-fibre repeatability and batch-to-batch reproducibility, while good linearity ranges and recoveries were obtained. The limits of detection ranged from 0.09 to 6.00 ng/g. Therefore, the results demonstrated that this novel method was an efficient pretreatment and enrichment procedure for the determination of trace carbamate pesticides in apples.

  16. Optimization and validation of liquid-liquid extraction with low temperature partitioning for determination of carbamates in water

    Energy Technology Data Exchange (ETDEWEB)

    Machado Goulart, Simone; Domingos Alves, Renata; Neves, Antonio Augusto; Queiroz, Jose Humberto de; Conde de Assis, Tamires [Departamento de Quimica, Universidade Federal de Vicosa, Vila Gianetti, Casa 24, 36 570-000 Vicosa, MG (Brazil); Queiroz, Maria Eliana L.R. de, E-mail: meliana@ufv.br [Departamento de Quimica, Universidade Federal de Vicosa, Vila Gianetti, Casa 24, 36 570-000 Vicosa, MG (Brazil)

    2010-06-25

    Using a 2{sup 3} experimental design, liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for analysis of three carbamates (aldicarb, carbofuran and carbaryl) in water samples. In this method, 2.0 mL of sample is placed in contact with 4.0 mL of acetonitrile. After agitation, the sample is placed in a freezer for 3 h for phase separation. The organic extract is analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). For validation of the technique, the following figures of merit were evaluated: accuracy, precision, detection and quantification limits, linearity, sensibility and selectivity. Extraction recovery percentages of the carbamates aldicarb, carbofuran and carbaryl were 90%, 95% and 96%, respectively. Even though extremely low volumes of sample and solvent were used, the extraction method was selective and the detection and quantification limits were between 5.0 and 10.0 {mu}g L{sup -1}, and 17.0 and 33.0 {mu}g L{sup -1}, respectively.

  17. Optimization and validation of liquid-liquid extraction with low temperature partitioning for determination of carbamates in water

    International Nuclear Information System (INIS)

    Using a 23 experimental design, liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for analysis of three carbamates (aldicarb, carbofuran and carbaryl) in water samples. In this method, 2.0 mL of sample is placed in contact with 4.0 mL of acetonitrile. After agitation, the sample is placed in a freezer for 3 h for phase separation. The organic extract is analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). For validation of the technique, the following figures of merit were evaluated: accuracy, precision, detection and quantification limits, linearity, sensibility and selectivity. Extraction recovery percentages of the carbamates aldicarb, carbofuran and carbaryl were 90%, 95% and 96%, respectively. Even though extremely low volumes of sample and solvent were used, the extraction method was selective and the detection and quantification limits were between 5.0 and 10.0 μg L-1, and 17.0 and 33.0 μg L-1, respectively.

  18. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of selected carbamate pesticides in water by high-performance liquid chromatography

    Science.gov (United States)

    Werner, S.L.; Johnson, S.M.

    1994-01-01

    As part of its primary responsibility concerning water as a national resource, the U.S. Geological Survey collects and analyzes samples of ground water and surface water to determine water quality. This report describes the method used since June 1987 to determine selected total-recoverable carbamate pesticides present in water samples. High- performance liquid chromatography is used to separate N-methyl carbamates, N-methyl carbamoyloximes, and an N-phenyl carbamate which have been extracted from water and concentrated in dichloromethane. Analytes, surrogate compounds, and reference compounds are eluted from the analytical column within 25 minutes. Two modes of analyte detection are used: (1) a photodiode-array detector measures and records ultraviolet-absorbance profiles, and (2) a fluorescence detector measures and records fluorescence from an analyte derivative produced when analyte hydrolysis is combined with chemical derivatization. Analytes are identified and confirmed in a three-stage process by use of chromatographic retention time, ultraviolet (UV) spectral comparison, and derivatization/fluorescence detection. Quantitative results are based on the integration of single-wavelength UV-absorbance chromatograms and on comparison with calibration curves derived from external analyte standards that are run with samples as part of an instrumental analytical sequence. Estimated method detection limits vary for each analyte, depending on the sample matrix conditions, and range from 0.5 microgram per liter to as low as 0.01 microgram per liter. Reporting levels for all analytes have been set at 0.5 microgram per liter for this method. Corrections on the basis of percentage recoveries of analytes spiked into distilled water are not applied to values calculated for analyte concentration in samples. These values for analyte concentrations instead indicate the quantities recovered by the method from a particular sample matrix.

  19. Summary of Validation of Multi-Pesticide Methods for Various Pesticide Formulations

    International Nuclear Information System (INIS)

    The validation of multi-pesticide methods applicable for various types of pesticide formulations is treated. In a worked-out practical example, i.e. lambda cyhalothrin, the theoretical considerations outlined in the General Guidance section are put into practice. GC conditions, selection of an internal standard and criteria for an acceptable repeatability of injections are outlined, followed by sample preparation, calibration, batch analysis and confirmation of results through comparison using different separation columns. Complete sets of data are displayed in tabular form for other pesticide active ingredients and real formulations. (author)

  20. HPLC-MS测定白酒中氨基甲酸酯类农药残留%Determination of carbamates pesticides in liquor by HPLC/MS

    Institute of Scientific and Technical Information of China (English)

    谭文渊; 袁东; 付大友; 李艳清; 王蓉

    2012-01-01

    A HPLC/MS method has been established for the determination of ten carbamates pesticides in liquor. The chromatographic conditions are as follows: Column of Phenomenex-Luna CN 100 A(250 mm×.6 mm×5 pm), and mobile phase was acetonitrile-water(20:80-80:20 within 40 minutes), flow rate was 1.0 mL/min, wavelength was 195 nm, column temperature was 25 ℃ and the injection volume was 20 μl.. MS conditions: Scanning range is 50-350 m/z, temperature of drying gas is 350 %, flow rate of drying gas is 8.0 mL/min, pressure of the evaporative gas is 275.86 kPa. The liquor samples were treated by SPE(solid phase extraction, NH2) and then concentrated by nitrogen-blow. Results showed that the standard curves of ten carbamates were linear over the quality range of 0.05-3 μg/mL, the correlation coefficient r were over 0.99. The average recovery of carbamates were 72.6%-97.6%, RSD were 2.6%-5.9%. Conclusion: this method was accurate, rapid, sensitive for the determination of carbamates pesticides in liquor by HPLC/MS.%建立了一种同时对白酒中10种氨基甲酸酯类农药残留的HPLC-MS测定方法。色谱条件:色谱柱Phenomenex-LunaCN100A(250mm×4.6mm×5μm),流动相乙腈-水(在40min内乙腈由20%变为80%),流速1.00mL/min,检测波长195nm,柱温25℃,进样量20μL。质谱条件:电喷雾离子源(ESI+源),扫描范围(m/z)为50~350,干燥气温度350℃,干燥气流速8.0mL/min,雾化气压力275.86kPa。样品制备:白酒样品用固相萃取处理后,氮吹浓缩,乙腈定容至2mL。结果表明,10种氨基甲酸酯类农药残留在0.05~3μg范围积线性关系良好,相关系数R2〉0.99。平均回收率在72.6%和97.6%,RSD在2.6%~5.9%之间。结论:方法灵敏度高、操作简便、结果准确,可用于酒样中痕量农药残留的含量测定。

  1. Determination of 7 carbamate pesticides in water by solid phase extraction-gas chromatography%固相萃取-气相色谱法测定水中7种氨基甲酸酯农药

    Institute of Scientific and Technical Information of China (English)

    周伦敏; 陆昱养; 何云亚

    2013-01-01

    目的:建立应用气相色谱-氮磷检测器结合固相萃取测定水中7种氨基甲酸酯农药的方法.方法:水样经ENVI-Carb固相萃取柱富集,以二氯甲烷+丙酮(1+1)洗脱,采用DB-1701毛细管柱和氮磷检测器进行检测.结果:7种氨基甲酸酯农药在DB-1701毛细管柱上均能得到很好分离,回收率在82.0%~101.5%,相对标准偏差为2.9%~10.5%.结论:本方法简便、快速、灵敏,可用于水中氨基甲酸酯农药的检测.%Objective:To establish a method for determination of 7 carbamate pesticides in water by gas chromatography-nitrogen phosphorus detector combined with solid-phase extraction.Methods:The target pesticides in water samples were enrichmented with ENVI-Carb solid phase extraction column,and eluted with dichloromethane and acetone(1 + 1),and separated with DB-1701 capillary column and detected with GC-NPD.Results:Seven carbamate pesticides could be well separated,the recovery rates were 82.0% ~ 101.5%,with the relative standard deviation of 2.9% ~ 10.5%.Conclusion:This method was simple,rapid and sensitive and it can be applied for analysis of carbamate pesticides in water.

  2. Rapid Determination of Organic Phosphorus and Carbamate Pesticides in Samples%样品中有机磷与氨基甲酸酯类农药快速检测方法的建立

    Institute of Scientific and Technical Information of China (English)

    卫海燕; 邵华

    2011-01-01

    目的 建立现场快速筛选区分有机磷农药和氨基甲酸酯类农药的方法.方法 在薄层色谱原理基础上,利用毛细管效应制备微色谱柱检测仪,检测2类农药.结果 该方法可以对有机磷农药和氨基甲酸酯类农药作出快速的定性分析,且最低检出量可达到10 μg.结论 该法操作简便,高效,重现性好,且试剂用量少,是批量农药样品定性检测和突发农药中毒事件现场快速筛选的一种新方法.%[Objective]To establish the method for rapid filtering organophosphorus pesticides and carbamate pesticides.[Methods]Based on the principle of thin-layer chromatography, the micro-column detector was prepared by using capillary effect, and was used to detect 2 kinds of pesticides.[Results]The method could make qualitative and quantitative analysis of organophosphorus peaticides and carbamate pesticides, and the minimum detection limit was 10 μg.[Conclusion]The method is simple, efficient, reproducible, with less reagent consumption, and it is a new method for qualitative detection of bulk samples of pesticides and rapid pesticide poisoning filtering in emergency incident.

  3. Applicability of a carbamate insecticide multiresidue method for determining additional types of pesticides in fruits and vegetables.

    Science.gov (United States)

    Krause, R T; August, E M

    1983-03-01

    Several fruits and vegetables were fortified at a low (0.02-0.5 ppm) and at a high (0.1-5 ppm) level with pesticides and with a synergist, and recoveries were determined. Analyses were performed by using 3 steps of a multiresidue method for determining N-methylcarbamates in crops: methanol extraction followed by removal of plant co-extractives by solvent partitioning and chromatography with a charcoal-silanized Celite column. Eleven compounds were determined by using a high performance liquid chromatograph equipped with a reverse phase column and a fluorescence detector. Twelve additional compounds were determined by using a gas-liquid chromatograph equipped with a nonpolar packed column and an electron capture or flame photometric detector. Recoveries of 10 pesticides (azinphos ethyl, azinphos methyl, azinphos methyl oxygen analog, carbaryl, carbofuran, naphthalene acetamide, naphthalene acetic acid methyl ester, napropamide, phosalone, and phosalone oxygen analog) and the synergist piperonyl butoxide, which were determined by high performance liquid chromatography, averaged 100% (range 86-117) at the low fortification level and 102% (range 93-115) at the high fortification level. Quantitative recovery of naphthalene acetamide through the method required that an additional portion of eluting solution be passed through the charcoal column. Recoveries of 7 additional pesticides (dimethoate, malathion, methyl parathion, mevinphos, parathion, phorate oxygen analog, and pronamide), which were determined by gas-liquid chromatography (GLC), averaged 108% (range 100-120) at the low fortification level and 107% (range 99-122) at the high fortification level. DDT, diazinon, dieldrin, phorate, and pirimiphos ethyl, which were determined by GLC, were not quantitatively recovered. PMID:6853408

  4. A novel miniaturized zinc oxide/hydroxylated multiwalled carbon nanotubes as a stir-brush microextractor device for carbamate pesticides analysis.

    Science.gov (United States)

    Makkliang, Fonthip; Kanatharana, Proespichaya; Thavarungkul, Panote; Thammakhet, Chongdee

    2016-04-21

    A novel miniaturized "stir-brush microextractor" was prepared using a zinc oxide/hydroxylated multiwalled carbon nanotubes (ZnO/MWCNTs-OH) coated stainless steel brush connected to a small dc motor. The synthesized zinc oxide on each strand of stainless steel had a flower-like nanostructure when observed by a scanning electron microscope (SEM). This structure produced a large surface area before it was coated with the hydroxylated multiwalled carbon nanotubes sorbent. Under optimal conditions, the developed device provided a good linearity for the extraction of carbofuran and carbaryl, in the range of 25-500 ng mL(-1) and 50-500 ng mL(-1), respectively, with low limits of detection of 17.5 ± 2.0 ng mL(-1) and 13.0 ± 1.8 ng mL(-1). It also provided a good stir-brush-to-stir-brush reproducibility (% relative standard deviation < 5.6%, n = 6). The device was applied for the extraction and preconcentration of carbamate pesticides in fruit and vegetable samples prior to analysis with a gas chromatograph coupled with a flame ionization detector (GC-FID). Carbofuran was found at 9.24 ± 0.93 ng g(-1) and carbaryl was detected at 7.05 ± 0.61 ng g(-1) with good recoveries in the range of 73.7 ± 10.0% to 108.4 ± 2.6% for carbofuran and 75.7 ± 10.0% to 111.7 ± 5.7% for carbaryl. PMID:27026597

  5. UPLC-MS/MS测定中药材中19种氨基甲酸酯农药残留量%Determination of Nineteen Carbamate Pesticides in Chinese Medicinal Materials by UPLC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    张燕; 杨钊; 金红宇; 孙磊; 李欣荣; 吴爱英

    2011-01-01

    OBJECTIVE To establish a method for the determination of 19 carbamate pesticides in Chinese medicinal materials by UPLC triple-quadrupole tandem mass spectrometer.METHODS The samples were determinated by multi-reactions monitoring (MRM) technology.The separation was performed on a Waters ACQUITY UPLC (R) BEH C18 column with acetonitrile -0.1% formic acid ( 1:1 ) with a flow rate of 0.2 mL min-1.Ion mode was set as ESI+.RESULTS The standard curves of the 19 carbamate pesticides showed good linearity over the concentration range of 1.0 - 100 μg · L-1 (r =0.994 7 -0.999 7), respectively.The LODs of 19 carbamate pesticides were in the range of 0.02 - 0.46 μg · L- 1 and the average recoveries were 73.2% - 119.7% at three levels.CONCLUSION The method is rapid, sensitive and suitable for the determination of 19 carbamate pesticides in Chinese medicinal materials.%目的 建立测定中药材中19种氨基甲酸酯农药残留量的超高效液相-串联四级杆质谱方法.方法 多反应监测模式测定,以Waters ACQUITY UPLC(R) BEH C18进行分离,乙腈-0.1%甲酸溶液(1:1),流速:0.2 mL·min-1.离子化模式:ESI+.结果 19种农药测定的线性范围在1.0~100.0 μg·L-1之间,r分别在0.994 7~0.999 7之间,检出质量浓度分别在0.02~0.46μg·L-1之间,3个水平的回收率分别在73.2%~119.7%之间.结论 该方法快速、准确、灵敏,可用于中药材中氨基甲酸酯类农药残留的测定.

  6. 2010年杭州市蔬菜有机磷和氨基甲酸酯农药残留状况分析%Analysis of organophosphorus and carbamate pesticide residues in vegetables collected from Hangzhou in 2010

    Institute of Scientific and Technical Information of China (English)

    何良兴; 张瓅文; 李燕

    2011-01-01

    目的:了解杭州市蔬菜农药残留情况,为蔬菜质量安全的监管和控制工作提供科学依据.方法:采集蔬菜样品446577批次,测定有机磷和氨基甲酸酯农药残留量,并对结果进行分析总结.结果:蔬菜年均农药超标率为0.09%,残留农药以有机磷为主,不同品种蔬菜的超标率与超标农药类型都不同,杭州本地与外地蔬菜农药超标率没有显著不同.结论:杭州市蔬菜农药残留水平较低,质量安全状况良好,但禁用农药还需要进一步加强监管.%Objective: To investigate the conditions of organophosphorus and carbamate pesticide residues in vegetables in Hangzhou in order to provide the basis for surveillance and control of vegetables safety. Methods: The total 446,577 samples of vegetables were collected and their residues of organophosphorus and carbamate were measured. At last, the results were analysised and summaried. Results: The disqualification rate of vegetables is 0.09%. The organophosphorus is the main pesticide residues. The disqualification rate and the type of pesticide residues varies in different kinds of vegetables. There's no difference in the disqualification rate of vegetables between Hangzhou and other places. Conclusion: The level of pesticide residues is low,and vegetable quality of Hangzhou is good, but supervision and administration on the forbidden pesticides should be strengthened.

  7. Adsorption of toxic carbamate pesticide oxamyl from liquid phase by newly synthesized and characterized graphene quantum dots nanomaterials.

    Science.gov (United States)

    Agarwal, Shilpi; Sadeghi, Nima; Tyagi, Inderjeet; Gupta, Vinod Kumar; Fakhri, Ali

    2016-09-15

    Graphene quantum dots have been synthesized using the microwave-assisted hydrothermal route. The surface textural and morphological structure of synthesized adsorbent i.e. graphene quantum dots was analyzed using various analytical techniques such as X-ray diffraction, Transmission electron Microscopy, Atomic Force Microscopy and N2 adsorption-desorption instrumental techniques. The application of graphene quantum dots as an adsorbent for the removal of noxious pesticide compound i.e. oxamyl from aqueous solutions was well investigated and elucidated. The impact of several effective parameters such as effect of agitation speed, pH, adsorbent dose, contact time, temperature and initial concentration on sorption efficiency was studied and optimized using batch adsorption experiments. The optimized pH for maximum oxamyl adsorption was found to be 8.0 and for the maximum adsorption rates the adsorbent dose of 0.6g was found to be optimum to carry out the adsorption with in less than 25min of contact time. From the results obtained, it is clear that for all contact times, an increase in oxamyl concentration resulted in increase in the percent oxamyl removal. The adsorption equilibrium and kinetic data were well fitted and found to be in good agreement with the Langmuir isotherm and pseudo-second-order kinetic model. PMID:27362399

  8. Study on the Interaction between Humic Substances in Soil and Carbamate Pesticides Using Fluorescence Quenching Titration Method%荧光猝灭滴定法研究土壤腐殖质与氨基甲酸酯类农药相互作用

    Institute of Scientific and Technical Information of China (English)

    施国兰; 郑博福; 白英臣; 吴丰昌; 吴代赦

    2012-01-01

    为研究氨基甲酸酯类农药在溶解有机质参与下的迁移转化过程,利用荧光猝灭滴定法研究了土壤HS(腐殖质)与氨基甲酸酯类农药的相互作用.结果表明,呋喃丹和西维因的荧光都能不同程度地被FA(富里酸)和HA(腐殖酸)猝灭,主要猝灭机理为静电结合猝灭.采用静态猝灭模型计算出氨基甲酸酯类农药与HS的K(结合常数),lg K由大到小为呋喃丹-HA(4.96)>西维因-HA(4.93)>呋喃丹-FA(4.72)>西维因-FA(4.68).HA与氨基甲酸酯类农药的lgK明显大于FA与氨基甲酸酯类农药,表明HS与氨基甲酸酯类农药间的作用力有疏水作用.进一步研究表明,氢键作用对HS与氨基甲酯类农药结合有一定的影响.%To reveal the mechanisms of transport and conversion of carbamate pesticides in the presence of dissolved organic matters, the fluorescence quenching titration method was applied to investigate the interactions between carbamate pesticides and humic substances in soil. The results showed that the intrinsic fluorescence of carbofuran and carbaryl was quenched by the fulvic and humic acids to varying degrees. Static quenching was the primary mechanism during this process. The binding constants (K) of carbamate pesticides and humic substances were estimated using the fluorescence static quenching model. The order of lg K were: those of carbofuran and humic acid (4. 96) > those of carbaryl and humic acid (4. 93) > those of carbofuran and fulvic acid (4. 72) > those of carbaryl and fulvic acid (4. 68). The values of lg K of carbamate pesticides and humic acids were clearly higher than those of carbamate pesticides and fulvic acids. This result indicated that the hydrophobic force is one of the main interactions between carbamate pesticides and humic substances, and further proved that hydrogen bonding could slightly affect the bonding of carbamate pesticides and humic substances.

  9. Study on carbamate pesticides by capillary electrophoresis with laser-induced fluorescence detection%CE-LIF在氨基甲酸酯类农药研究中的应用

    Institute of Scientific and Technical Information of China (English)

    杨玉林; 赵晓寅; 赵文杰; 周天舒

    2012-01-01

    用毛细管电泳激光诱导荧光检测法(CE-LIF),对灭除威(XMC)、混杀威(2,3,5-trime-thacarb)和灭虫威(mercaptodimethur)等3种氨基甲酸酯类农药进行了研究.在碱性条件下,氨基甲酸酯类农药水解产生甲胺并与荧光衍生试剂4-氯-7-硝基-2,1,3-苯并二唑(NBD-Cl)发生衍生化反应,产物经毛细管电泳激光诱导荧光检测法测定.对影响水解、衍生以及毛细电泳分离的因素如缓冲液酸度、浓度和衍生试剂的浓度等进行了详细讨论;在最佳条件下,3种农药的检出限分别可达3.0×10-9、1.0×10-9和3.0×10-9 mol/L,并测定了它们的水解速率常数及活化能.该方法不仅可对氨基甲酸酯类农药进行测定,同时也可用于对这类农药的一些理化常数的测定.%A sensitive and rapid capillary electrophoresis method with laser-induced fluorescence detection (CE-LIF) was developed for the determination of carbamate pesticides (including (3,5-dimethylphenyl) N-methylcarbamate (XMC), and mercaptodimethur). In alkaline solution, carbamate was hydrolyzed to methylamine, which can be derivatized by 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-C1) and detected by CE-LIF. Several parameters which influence the hydrolysis, derivatization and electrophoresis separation, such as pH, concentration of buffer solution and concentration of NBD-C1, were investigated. The detection limits of the three carbamates were 3. 0×10-9, 1. 0 ×10-9 and 3. 0 ×10-9 mol/L, respectively. The proposed method was successfully employed to determine the rate constants and activation energies for carbamates hydrolysis.

  10. Overall and class-specific scores of pesticide residues from fruits and vegetables as a tool to rank intake of pesticide residues in United States: A validation study.

    Science.gov (United States)

    Hu, Yang; Chiu, Yu-Han; Hauser, Russ; Chavarro, Jorge; Sun, Qi

    2016-01-01

    Pesticide residues in fruits and vegetables are among the primary sources of pesticide exposure through diet, but the lack of adequate measurements hinder the research on health effects of pesticide residues. Pesticide Residue Burden Score (PRBS) for estimating overall dietary pesticide intake, organochlorine pesticide score (OC-PRBS) and organophosphate pesticide score (OP-PRBS) for estimating organochlorine and organophosphate pesticides-specific intake, respectively, were derived using U.S. Department of Agriculture Pesticide Data Program data and National Health and Nutrition Examination Survey (NHANES) food frequency questionnaire data. We evaluated the performance of these scores by validating the scores against pesticide metabolites measured in urine or serum among 3,679 participants in NHANES using generalized linear regression. The PRBS was positively associated with a score summarizing the ranks of all pesticide metabolites in a linear fashion (p for linear trend vegetables with high vs. low pesticide residues, respectively (p for trend vegetables (p for trend 0.07) than from less contaminated Fruits and vegetables (p for trend 0.63), although neither of the associations achieved statistical significance. The PRBS and the class-specific scores for two major types of pesticides were significantly associated with pesticide biomarkers. These scores can reasonably rank study participants by their pesticide residue exposures from fruits and vegetables in large-scale environmental epidemiological studies. PMID:27128714

  11. Pesticides

    Science.gov (United States)

    ... rodents, noxious weeds, and insects. Pesticides help prevent crop loss and, potentially, human disease. According to the ... pesticides. DO NOT mix pesticides. DO NOT set traps or place bait in areas where children or ...

  12. Principles of Single-Laboratory Validation of Analytical Methods for Testing the Chemical Composition of Pesticides

    International Nuclear Information System (INIS)

    Underlying theoretical and practical approaches towards pesticide formulation analysis are discussed, i.e. general principles, performance characteristics, applicability of validation data, verification of method performance, and adaptation of validated methods by other laboratories. The principles of single laboratory validation of analytical methods for testing the chemical composition of pesticides are outlined. Also the theoretical background is described for performing pesticide formulation analysis as outlined in ISO, CIPAC/AOAC and IUPAC guidelines, including methodological characteristics such as specificity, selectivity, linearity, accuracy, trueness, precision and bias. Appendices I–III hereof give practical and elaborated examples on how to use the Horwitz approach and formulae for estimating the target standard deviation towards acceptable analytical repeatability. The estimation of trueness and the establishment of typical within-laboratory reproducibility are treated in greater detail by means of worked-out examples. (author)

  13. GC-MS法高灵敏检测蔬菜中氨基甲酸酯农药残留%Detection of pesticides residues of carbamate in vegetables by GC-MS

    Institute of Scientific and Technical Information of China (English)

    王俊; 管有志; 于微; 谭洪兴; 朱李佳; 刘小立

    2013-01-01

    目的 建立使用气质联用法同时检测蔬菜中多种氨基甲酸酯快速灵敏的检测方法.方法 样品经乙腈提取,固相萃取柱净化,并建立一种快速测定蔬菜中6种氨基甲酸酯类农药残留(异丙威、仲丁威、残杀威、抗芽威、速灭威、甲奈威)的气相色谱质谱联用(GC-MS)检测方法.同时对22种蔬菜中的多种氨基甲酸酯类农药进行定性及定量分析. 结果 建立一种快速测定蔬菜中6种氨基甲酸酯类农药残留的GC-MS方法,该方法对6种氨基甲酸酯类农药的相对标准偏差为1.06%~3.73%,回收率为86.5%~112.3%,并具有较好的精密度.在应用该方法检测的22种蔬菜中,一份空心菜检测出残杀威,一份香菜中检测出异丙威. 结论 本文建立的快速测定蔬菜中6中氨基甲酸酯类农药的GC-MS方法准确可靠,灵敏度高,可应用于蔬菜中多种氨基甲酸酯农药的同时测定.%Objective To set up a reliable method for determination of six carbamates in vegetables by using GC-MS.. Methods Samples were extracted with acetonitrile and then purified by solid-phase extraction (SPE). A method on rapid detection of six carbamates (Isoprocarb,BPMC,Propoxur,Pirimicarb,MTMC,Carbaryl)in samples by GC-MS has been established. Qualitative and quantitative analysis of pesticide residues in 22 vegetables from local supermarket have been performed by the proposed method. Results The relative standard deviations of the method were between 1.06% and 3.73%,and the method recoveries were in the range of 86.5-112.3% with good precision. Propoxur in water spinach and Isoprocarb in caraway have positive test results in our experiments. Conclusions The method was highly sensitive with satisfied recovery and it could be applied to detect six carbamates residues in vegetables quickly and accurately.

  14. UPLC -MS/MS determination of carbamate pesticides in traditional Chinese medicine%超高效液相色谱-串联质谱法测定中草药中氨基甲酸酯类农药残留量

    Institute of Scientific and Technical Information of China (English)

    李娜; 刘磊; 邵辉; 李辉; 张玉婷; 宋海菲; 郭永泽

    2011-01-01

    目的:结合固相萃取技术,克服了中草药样品中复杂的基质干扰问题,建立超高效液相色谱-串联质谱( UPLC - MS/MS)法检测中药材中15种氨基甲酸酯类杀虫剂的残留量.方法:样品中残留的农药经乙腈提取,PSA固相萃取柱净化后,采用UPLC - MS/MS法进行测定.结果:15种农药在其各自的浓度范围内,线性关系良好,相关系数在0.995 ~0.999之间.在定量限(LOQ)、5倍定量限和10倍定量限3个添加浓度水平,平均加标回收率在61.8% ~98.1%之间;RSD在1.8% ~ 14.8%之间.结论:该方法操作简便,净化效果好,灵敏度高,可为中药材中氨基甲酸酯类杀虫剂污染状况调查提供检测方法支持.%Objective:An ultra performance liquid chromatography - tandem mass spectrometric method was developed for the determination of 15 carbamate pesticides in traditional Chinese medicine. Method:Pesticides were extracted with acetonitrile,cleaned up by PSA solid phase extraction column,and then analyzed by UPLC -MS/MS. Result:The standard calibration curves for 15 carbamate pesticides showed high correlation coefficient (0.995 -0. 999) over their respective concentration range. The average recovery of 15 carbamate pesticides at the three fortification levels ( LOQ,5 LOQ and 10 LOQ) was between 61. 8% and 98. 1% with the relative standard deviation between 1. 8% and 14. 8%. Conclusion:It was indicated that the method developed in this study is easier,more sensitive and has a better purification effect. So,this method can be further applied to investigate the contamination status of traditional Chinese medicine by the carbamate pesticides.

  15. Method development and validation for the determination of pesticides in green coffee by gas chromatography

    International Nuclear Information System (INIS)

    This study describes the implementation and validation of a multiresidue methodology for the determination of organochlorine, organophosphorus and pyrethroids pesticides in green coffee. Pesticides residues were extracted from green samples with an acetone-water (2:1) mixture followed by ethyl acetate cyclohexane (1:1) partitioning. The clean up steps include gel permeation chromatography and mini column chromatography using silica gel. Final determination was carried out by high-resolution gas chromatography with a pulsed split less injection mode and simultaneous detection by μ-ECD and NPD coupled in parallel. The methodology is specific, selective precise and accurate. Recoveries of majority of pesticides from spiked samples range from 70 to 110% at fortification levels of 0.038 mg/kg-1.536 mg/kg with limit of quantitation between 0.011 mg/kg and 0.100 mg/kg

  16. Detection of 20 carbamate pesticides in asparagus by ultra performance liquid chromatography-electrospray ionization-mass spectrometry-mass spectrometry%超高效液相色谱-电喷雾串联四极杆质谱法检测芦笋中20种氨基甲酸酯类农药残留

    Institute of Scientific and Technical Information of China (English)

    赵晓琳; 霍乃蕊; 花锦; 宋欢

    2015-01-01

    目的:建立芦笋及其罐头制品中20种氨基甲酸酯类农药残留的定性定量分析方法。方法采用改进的 QuEchERS 法提取和净化,利用超高效液相色谱-电喷雾串联四极杆质谱仪,在多反应监测正离子扫描模式下对样品进行添加回收率试验。结果分别对绿芦笋、白芦笋、绿芦笋罐头、白芦笋罐头4种空白基质添加0.005~0.050 mg/kg农药样品进行回收率试验,回收率为62.44%~85.99%,定量限均为0.005 mg/kg, RSD均小于9%。结论该方法简单快速,灵敏度高,能够同时满足芦笋及其罐头制品中20种氨基甲酸酯类农药残留的检测要求。%Objective To establish an ultra performance liquid chromatography-electrospray ionization-mass spectrometry-mass spectrometry method for detecting of 20 kinds of carbamate pesticides in asparagus and asparagus products. Methods Samples were extracted by modified QuEchERS method, and the mode of multi-reaction monitoring positive ion scanning was applied for analysis by ultra high performance liquid chromatography-electrospray tandem quadrupole mass spectrometer. Results The blank matrixes (green asparagus, white asparagus, canned white asparagus, canned white asparagus) were added 0.005~0.050 mg/kg carbamate pesticides separately and recovery tests were performed. Results demonstrated that the recovery rates were in the range of 62.44%~85.99% and the limits of quantification were 0.005 mg/kg for all the 20 carbamate pesticides tested with the relative standard deviations (RSDs) below 9%. Conclusion The method, not only simple and fast but also high sensitive, can satisfy the international detection requirement for 20 carbamate pesticides residue in asparagus product simultaneously.

  17. PSA分散固相萃取液相色谱柱后衍生荧光法测定蔬菜和水果中的13种氨基甲酸酯%Study on determination of thirteen carbamate pesticides in vegetables and fruits by HPLC with post-column derivatization and fluorescence detection after PSA dispersive solid-phase extraction cleanup

    Institute of Scientific and Technical Information of China (English)

    于彦彬; 谭丕功; 曲璐璐; 王学松

    2009-01-01

    建立了PSA分散固相萃取净化, 液相色谱柱后衍生荧光法测定蔬菜和水果中13种氨基甲酸酯农药的分析方法. 在建立的测定条件下, 13种氨基甲酸酯的含量与峰面积之间成线性关系, 相关系数大于0.994, 保留时间的相对标准偏差在0.03%~0.22%之间, 检测下限在2.00~2.28 μg/kg范围内. 西瓜、杏、茄子及胡萝卜中13种氨基甲酸酯的平均回收率在71.7%~110%之间, 相对标准偏差在0.68%~15%之间, 分析结果优于氨基柱固相萃取法.%Determination of thirteen carbamate pesticides residues in vegetables and fruits by HPLC with PSA dispersive solid-phase extraction cleanup and post-column derivatization fluorescence detection is developed. Under the optimal determination conditions, the detection limits of thirteen carbamate pesticides are in the range of 2.00~2.28 jug/kg. There is a good linear relationship in the content range of determination. The correlation coefficients of thirteen carbamate pesticides are more than 0.99. The relative standard deviations of retention time are in the range of 0.03%~0.22% . It is simpler in sample handling by PSA dispersive solid-phase extraction than by NH2 column solid-phase extraction. There are little interference in matrix, and high quality results are obtained. The spiked average recoveries of thirteen carbamate pesticide residues ranged from 71.7%~110% with RSDs of 0.68%~15% for watermelon, apricot, eggplant and carrot, The results are very satisfactory.

  18. DETERMINATION OF CARBAMATE PESTICIDE RESIDUES IN WHEAT USING MATRIX SOLID-PHASE DISPERSION EXTRACTION AND LIQUID CHROMATOGRAPHY%基质固相分散萃取-液相色谱法测定小麦中多种氨基甲酸酯农药残留的研究

    Institute of Scientific and Technical Information of China (English)

    吴丽华; 田忙雀; 杨勤元

    2011-01-01

    研究了C18基质固相分散萃取(MSPDE),高效液相色谱-柱后衍生-荧光检测器测定小麦中6种氨基甲酸酯农药的方法.通过对色谱条件、基质固相分散材料的选择及其与样品的比例、洗脱条件以及加标回收率进行试验,建立和优化了小麦中6种氨基甲酸酯农药的MSPDE-HPLC-FLD多残留分析方法.结果显示,该方法对小麦样品中6种氨基甲酸酯农药的回收率为82.1%~94.0%,变异系数≤3.54%,方法的最低检出限为0.009 2~0.038 mg/kg.研究证明,基质固相分散萃取-液相色谱-柱后衍生方法简便、快速、准确、灵敏、节省样品和有机溶剂,可满足小麦中多种氨基甲酸酯农药残留同时检测的需要.%We studied a method for determining 6 kinds of carbamate pesticides in wheat using C18 matrix solid-phase dispersion extraction (MSPDE), high performance liquid chromatography, post-column derivation technique and fluorescence detector. Through the tests of the chromatographic conditions, the selection of matrix solid-phase dispersion material and the ratio of matrix solid-phase dispersion to the sample, the elution conditions and the standard recovery, we established and optimized the MSPDE-HPLC-FLD multi-residue analysis method for determining 6 kinds of carbamate pesticides in wheat. The results showed that the yield of the 6 kinds of carbamate pesticides in wheat reached 82.1% to 94.0 %, the coefficient of variation was equal to or less than 3.54 %, and the lowest detection limit was 0.009 2 to 0.038 0 mg/kg. It is testified that the method is simple, rapid, accurate, sensitive, and saving of samples and organic solvent, and can meet the requirement for simultaneously determining multiple kinds of carbamate pesticides in wheat.

  19. Organophosphorus and carbamate insecticide poisoning.

    Science.gov (United States)

    Vale, Allister; Lotti, Marcello

    2015-01-01

    Both organophosphorus (OP) and carbamate insecticides inhibit acetylcholinesterase (AChE), which results in accumulation of acetylcholine (ACh) at autonomic and some central synapses and at autonomic postganglionic and neuromuscular junctions. As a consequence, ACh binds to, and stimulates, muscarinic and nicotinic receptors, thereby producing characteristic features. With OP insecticides (but not carbamates), "aging" may also occur by partial dealkylation of the serine group at the active site of AChE; recovery of AChE activity requires synthesis of new enzyme in the liver. Relapse after apparent resolution of cholinergic symptoms has been reported with OP insecticides and is termed the intermediate syndrome. This involves the onset of muscle paralysis affecting particularly upper-limb muscles, neck flexors, and cranial nerves some 24-96 hours after OP exposure and is often associated with the development of respiratory failure. OP-induced delayed neuropathy results from phosphorylation and subsequent aging of at least 70% of neuropathy target esterase. Cramping muscle pain in the lower limbs, distal numbness, and paresthesiae are followed by progressive weakness, depression of deep tendon reflexes in the lower limbs and, in severe cases, in the upper limbs. The therapeutic combination of oxime, atropine, and diazepam is well established experimentally in the treatment of OP pesticide poisoning. However, there has been controversy as to whether oximes improve morbidity and mortality in human poisoning. The explanation may be that the solvents in many formulations are primarily responsible for the high morbidity and mortality; oximes would not be expected to reduce toxicity in these circumstances. even if given in appropriate dose. PMID:26563788

  20. (BOSC) DOSE-RESPONSE MODELING FOR THE ASSESSMENT OF CUMULATIVE RISK DUE TO EXPOSURE TO N-METHYL CARBAMATE PRESTICIDES

    Science.gov (United States)

    THE US EPA'S N-METHYL CARBAMATE CUMULATIVE RISK ASSESSMENT (NMCRA) ASSESSES THE EFFECT ON ACETYLCHOLINE ESTERASE (AChE) ACTIVITY OF EXPOSURE TO 10 N-METHLY CARBAMATE (NMC)PESTICIDES THROUGH DIETARY, DRINKING WATER, AND RESIDENTIAL EXPOSURES. THESE DATA THUS INFORM, BUT DO NOT COM...

  1. 动态微波辅助萃取法快速萃取苹果中8种氨基甲酸酯类农药%Rapid extraction of carbamate pesticides from apple on dynamic microwave-assisted extraction

    Institute of Scientific and Technical Information of China (English)

    刘密兰; 曾庆磊; 丁兰; 金海燕

    2014-01-01

    目的:建立一种绿色的动态微波辅助快速萃取法结合高效液相色谱-串联质谱法测定苹果中8种氨基甲酸酯类农药的方法。方法以水为萃取溶剂,利用动态微波辅助萃取法对苹果中氨基甲酸酯类农药进行快速萃取;通过两步固相萃取法对所获得的萃取物进行净化和富集;采用高效液相色谱-串联质谱法对目标化合物进行测定。结果实验中对影响动态微波辅助萃取和固相萃取效率的实验条件进行了优化,最优的实验条件为:萃取剂为纯水;微波萃取功率为600 W;微波萃取时间为10 min;萃取剂流速为1.0 mL/min;固相萃取洗脱剂为2 mL的乙醇。8种氨基甲酸酯类农药在8.0~800 ng/g范围内成线性关系,相关系数为0.994~0.999;检出限为1.1~4.2 ng/g;方法的加标(8.0 ng/g)回收率为71%~90%。结论该方法可以用于苹果中氨基甲酸酯类农药的快速检测。%Objective A green and fast sample pretreatment method was proposed for determination of 8 carbamate pesticides from apple. Methods The 8 carbamate pesticides in apple samples were extracted by dynamic microwave-assisted extraction with water as extraction solvent. The extract obtained was purified by two steps SPE. Finally, the extract was injected into the LC-MS/MS system for analysis. The parameters which could affect the extraction efficiency were optimized. Results The optimized extraction conditions were observed at water as extraction solvent; 600 W of microwave forward power; extraction time, 10 min;extraction solvent flow-rate, 1.0 mL/min; 2 mL ethanol as the elution solvent of SPE. The linearity ranges of the proposed method from 8.0 to 800 ng/g were obtained and the correlation coefficient were 0.994~0.999. The limits of detection for the eight carbamate pesticides were in the range of 1.1~4.2 ng/g. The recoveries of the eight carbamate pesticides for the spiked samples (8.0 ng/g) were in the range of 71

  2. Acetylcholinesterase inhibition as an indicator of organophosphate and carbamate poisoning in Kenyan agricultural workers.

    NARCIS (Netherlands)

    Ohayo-Mitoko, G.J.A.; Heederik, D.; Kromhout, H.; Omondi, B.E.O.; Boleij, J.S.M.

    1997-01-01

    Acetylcholinesterase inhibition was determined for 666 Kenyan agricultural workers; 390 (58.6%) mainly pesticide applicators exposed to organophosphate and carbamate pesticides and 276 (41.4%) unexposed controls from four rural agricultural areas during 1993 and 1994. Baseline levels were depressed

  3. Method development and validation for the simultaneous determination of organochlorine and organophosphorus pesticides in a complex sediment matrix.

    Science.gov (United States)

    Alcántara-Concepción, Victor; Cram, Silke; Gibson, Richard; Ponce de León, Claudia; Mazari-Hiriart, Marisa

    2013-01-01

    The Xochimilco area in the southeastern part of Mexico City has a variety of socioeconomic activities, such as periurban agriculture, which is of great importance in the Mexico City metropolitan area. Pesticides are used extensively, some being legal, mostly chlorpyrifos and malathion, and some illegal, mostly DDT. Sediments are a common sink for pesticides in aquatic systems near agricultural areas, and Xochimilco sediments have a complex composition with high contents of organic matter and clay that are ideal adsorption sites for organochlorine (OC) and organophosphorus (OP) pesticides. Therefore, it is important to have a quick, affordable, and reliable method to determine these pesticides. Conventional methods for the determination of OC and OP pesticides are long, laborious, and costly owing to the high volume of solvents and adsorbents. The present study developed and validated a method for determining 18 OC and five OP pesticides in sediments with high organic and clay contents. In contrast with other methods described in the literature, this method allows isolation of the 23 pesticides with a 12 min microwave-assisted extraction (MAE) and one-step cleanup of pesticides. The method developed is a simpler, time-saving procedure that uses only 3.5 g of dry sediment. The use of MAE eliminates excessive handling and the possible loss of analytes. It was shown that the use of LC-Si cartridges with hexane-ethyl acetate (75+25, v/v) in the cleanup procedure recovered all pesticides with rates between 70 and 120%. The validation parameters demonstrated good performance of the method, with intermediate precision ranging from 7.3 to 17.0%, HorRat indexes all below 0.5, and tests of accuracy with the 23 pesticides at three concentration levels demonstrating recoveries ranging from 74 to 114% and RSDs from 3.3 to 12.7%. PMID:24000760

  4. A Quantitative Structure Activity Relationship for acute oral toxicity of pesticides on rats: Validation, Domain of Application and Prediction

    OpenAIRE

    Hamadache, Mabrouk; Benkortbi, Othmane; Hanini, Salah; Amrane, Abdeltif; Khaouane, Latifa; Si Moussa, Cherif

    2016-01-01

    International audience Quantitative Structure Activity Relationship (QSAR) models are expected to play an important role in the risk assessment of chemicals on humans and the environment. In this study, we developed a validated QSAR model to predict acute oral toxicity of 329 pesticides to rats because a few QSAR models have been devoted to predict the Lethal Dose 50 (LD50) of pesticides on rats. This QSAR model is based on 17 molecular descriptors, and is robust, externally predictive and...

  5. Determination of Carbamate Pesticides Residues in Vegetables by High Performance Liquid Chromatography Coupled with Tandem Mass Spectrometry%高效液相色谱-串联质谱法测定蔬菜中氨基甲酸酯类农药残留

    Institute of Scientific and Technical Information of China (English)

    周长朋; 杨丽君; 徐成钢; 时文春; 王静

    2011-01-01

    A high performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the determination of 5 carbamate pesticides, including aldicarb, aldicarbsulfoxide, aldicarbsulfone, carbofuran and 3-hydroxycarbofuran in products of vegetables. Homogenized samples were extracted with acetonitrle. The extracts were dehydrated with sodium sulphate anhydrous. The extract layer was concentrated in 40°C by vacuum rotary steam to 1. 0 mL,and dried by nitrogen flowing,then redissolved in 0. 1% formic acid issolution. Identification of 5 carbamate pesticides was achieved by electospray ionization tandem mass spectrometry in positive mode using multiple reaction monitoring (MRM) and quantification analysis was performed with matrix-matched standard calibration. The results indicated that, under the optimal conditions, the calibration curves showed good linearity for 5 carbamate pesticides over the concentration range of 5. 0 - 100 jug/kg. Detection limits were 5. 0 μg/kg. The mean recoveries varied from 61. 3% to 123% at three spiked levels of 5. 0,10 and 20 μg/kg. The RSDs were less than 15%. This method is sensitive and reproducible,and suitable for the routine determination of 5 carbamate pesticides residues in vegetables.%建立了高效液相色谱-串联质谱(HPLC-MS/MS)法同时测定蔬菜中涕灭威、涕灭威砜、涕灭威亚砜、克百威、三羟基克百威5种氨基甲酸酯类农药残留的方法.样品均质后,经乙腈提取,无水硫酸钠脱水.提取液40℃减压旋蒸浓缩至1.0mL,氮气吹干后,0.1%甲酸水溶解定容;采用高效液相色谱-串联质谱电喷雾多反应监测模式检测.实验结果表明,5种氨基甲酸酯类农药在5.0~100 μg/kg范围内线性关系良好.检出限均为5.0μg/kg.6种空白基质样品中5.0、10、20 μg/kg 3水平的加标回收率为61.30%~123%,相对标准偏差均在15%以内.该方法操作简单、灵敏度高、重现性好,可用于蔬菜中5种氨

  6. Rapid determination of 8 urinary carbamate pesticides by liquid chromatography-tandem mass spectrometry%尿中8种氨基甲酸酯类农药快速测定的液相色谱-串联质谱法

    Institute of Scientific and Technical Information of China (English)

    刘华良; 王媛; 朱宝立

    2015-01-01

    目的 建立尿中8种氨基甲酸酯类农药同时测定的方法.方法 尿样用乙腈沉淀蛋白后,用液相色谱-串联质谱法进行测定,外标法定量,其中色谱柱采用C18超高效液相色谱柱,流动相为甲醇与乙酸铵溶液梯度淋洗,质谱采集方式为多反应监测.结果 样品中氨基甲酸酯类农药的线性范围为20~800 μg/L,当添加浓度为20、200、800 μg/L时,回收率为61.0%~121%,相对标准偏差为1.7%~5.5%.结论 该检测方法各项指标均符合GBZT 210.5-2008《职业卫生标准制定指南第5部分:生物材料中化学物质测定方法》的要求,适用于中毒患者尿中8种氨基甲酸酯类农药的同时检测.%Objective To establish a method for simultaneously determining the urinary concentrations of 8 carbamate pesticides.Methods After being purified by acetonitrile precipitation,urine samples were transferred to a liquid chromatography-tandem mass spectrometry system,and the concentrations of 8 carbamate pesticides were determined by external standard method.A C18 column was used for ultra-high-performance liquid chromatography;methanol/ammonium acetate solution was used as the mobile phase for gradient elution;the mass spectrometer was operated in a multi-reaction monitoring mode.Results The calibration curves were linear when the urinary concentrations of these carbamate pesticides were 20~800 μg/L,and the recovery rates were 61.0%~121% at spiked levels of 20,200 and 800 μg/L,with a relative standard deviation of 1.7%~5.5%.Conclusion This determination method meets the Guide for establishing occupational health standards-part 5:Determination methods of chemicals in biological materials,and can be used for simultaneous determination of 8 carbamate pesticides in the urine of poisoning patients.

  7. Development, validation and determination of multiclass pesticide residues in cocoa beans using gas chromatography and liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Zainudin, Badrul Hisyam; Salleh, Salsazali; Mohamed, Rahmat; Yap, Ken Choy; Muhamad, Halimah

    2015-04-01

    An efficient and rapid method for the analysis of pesticide residues in cocoa beans using gas and liquid chromatography-tandem mass spectrometry was developed, validated and applied to imported and domestic cocoa beans samples collected over 2 years from smallholders and Malaysian ports. The method was based on solvent extraction method and covers 26 pesticides (insecticides, fungicides, and herbicides) of different chemical classes. The recoveries for all pesticides at 10 and 50 μg/kg were in the range of 70-120% with relative standard deviations of less than 20%. Good selectivity and sensitivity were obtained with method limit of quantification of 10 μg/kg. The expanded uncertainty measurements were in the range of 4-25%. Finally, the proposed method was successfully applied for the routine analysis of pesticide residues in cocoa beans via a monitoring study where 10% of them was found positive for chlorpyrifos, ametryn and metalaxyl. PMID:25442595

  8. Simultaneous determination of airborne carbamates in workplace by high performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Li, Hong-Ping; Li, Jen-Hou; Li, Gwo-Chen; Jen, Jen-Fon

    2004-06-17

    A high performance liquid chromatography with fluorescence (HPLC-F) detector was examined to simultaneous determination of airborne carbamates in the workplace of manufactory. The OVS-2 air sampling tube filled with glass fiber filter or quartz fiber and combined filter/XAD-2 were evaluated to collect nine commonly used carbamates (Carbofuran, Isoprocarb, Methomyl, Metolcarb, Thiodicarb, Carbaryl, Oxamyl, Methiocarb, and Prpoxur) from the air of manufactory in high humidity country. After being extracted with acetonitrile from sampling tubes, the carbamates were determined by high performance liquid chromatography with fluorescence detection posterior to on-line derivatization. The collection of carbamates and the recovery of extraction from glass wool fiber in several concentration levels, and from quartz filter were evaluated. The storage stability of carbamates was also tested. Results indicated that the HPLC-fluorescence method offers satisfactory resolution and sensitivity in carbamate analysis. With the glass fiber filter and combined filter/XAD-2, the Carbofuran, Isoprocarb, Methomyl, Metolcarb, and Thiodicarb were stable for a 28-day storage test, Carbaryl and Oxamyl for 14 days, and Methiocarb and Prpoxur for 7 days. All of these pesticides were with detection limit of 3mugm(-3). It is suited for environmental monitoring. The airborne carbamates in different areas of the manufactory were measured.

  9. Research on detection method of pesticides residues of organic phosphorus and carbamate in vegetables and fruits%蔬菜、水果中16种有机磷和氨基甲酸酯农药残留检测方法研究

    Institute of Scientific and Technical Information of China (English)

    郝宁

    2012-01-01

    [ Objective]To establish a method for rapidly detecting 16 kinds of pesticides residues of organic phosphorus and carba-mate in vegetables and fruits [Methods] The detection was conducted by applying gas chromatography with quartz capillary, by u-sing nitrogen-phosphorus detector with high sensitivity and through extracting sample by acetonitrile and acetone. [ Results] the linear ranges of organophosphorus pesticides were 5. 0-1 000. 0 μg/kg, r>0. 999 0. The lowest determination limit was 0. 1- 0. 5 μg/kg, the recoveries were 66.0% -84.0% , and RSD was 4. 8% -9.5% [ Conclusion] This method can determine organic phosphorus and carbamate pesticides simultaneously in vegetables and fruits. It has the characteristics of high sensitivity, good separating effect, high recovery rate, small variance coefficient and low determination limit.%目的 建立一种快速测定蔬菜、水果中有机磷和氨基甲酸酯16种农药残留的方法.方法 应用石英毛细管气相色谱法,利用高灵敏氮磷检测器,用乙腈和丙酮提取样品进行检测.结果 该方法检测16种农药残留的线性范围为5.0~1 000.0 μg/kg,相关系数≥0.9990,最低检出浓度为0.1~0.5 μg/kg,样品加标回收率为66.0%~84.0%,RSD为4.8%~9.5%.结论 该方法能同时测定蔬菜、水果中的有机磷和氨基甲酸酯类农药,具有灵敏度高、分离效果好、回收率高、变异系数小、检出限低的特点.

  10. A Quantitative Structure Activity Relationship for acute oral toxicity of pesticides on rats: Validation, domain of application and prediction.

    Science.gov (United States)

    Hamadache, Mabrouk; Benkortbi, Othmane; Hanini, Salah; Amrane, Abdeltif; Khaouane, Latifa; Si Moussa, Cherif

    2016-02-13

    Quantitative Structure Activity Relationship (QSAR) models are expected to play an important role in the risk assessment of chemicals on humans and the environment. In this study, we developed a validated QSAR model to predict acute oral toxicity of 329 pesticides to rats because a few QSAR models have been devoted to predict the Lethal Dose 50 (LD50) of pesticides on rats. This QSAR model is based on 17 molecular descriptors, and is robust, externally predictive and characterized by a good applicability domain. The best results were obtained with a 17/9/1 Artificial Neural Network model trained with the Quasi Newton back propagation (BFGS) algorithm. The prediction accuracy for the external validation set was estimated by the Q(2)ext and the root mean square error (RMS) which are equal to 0.948 and 0.201, respectively. 98.6% of external validation set is correctly predicted and the present model proved to be superior to models previously published. Accordingly, the model developed in this study provides excellent predictions and can be used to predict the acute oral toxicity of pesticides, particularly for those that have not been tested as well as new pesticides.

  11. A Quantitative Structure Activity Relationship for acute oral toxicity of pesticides on rats: Validation, domain of application and prediction.

    Science.gov (United States)

    Hamadache, Mabrouk; Benkortbi, Othmane; Hanini, Salah; Amrane, Abdeltif; Khaouane, Latifa; Si Moussa, Cherif

    2016-02-13

    Quantitative Structure Activity Relationship (QSAR) models are expected to play an important role in the risk assessment of chemicals on humans and the environment. In this study, we developed a validated QSAR model to predict acute oral toxicity of 329 pesticides to rats because a few QSAR models have been devoted to predict the Lethal Dose 50 (LD50) of pesticides on rats. This QSAR model is based on 17 molecular descriptors, and is robust, externally predictive and characterized by a good applicability domain. The best results were obtained with a 17/9/1 Artificial Neural Network model trained with the Quasi Newton back propagation (BFGS) algorithm. The prediction accuracy for the external validation set was estimated by the Q(2)ext and the root mean square error (RMS) which are equal to 0.948 and 0.201, respectively. 98.6% of external validation set is correctly predicted and the present model proved to be superior to models previously published. Accordingly, the model developed in this study provides excellent predictions and can be used to predict the acute oral toxicity of pesticides, particularly for those that have not been tested as well as new pesticides. PMID:26513561

  12. Validation of thin-layer chromatographic methods for pesticide residue analysis. Results of the coordinated research projects 1996-2002

    International Nuclear Information System (INIS)

    Thin-layer chromatography (TLC) has a long history, but has been used only to a limited extent in pesticide residue analytical laboratories since gas liquid chromatography (GLC) and high performance liquid chromatography (HPLC) became readily available. Recent developments in the quality of plate coating and detection systems, as well as in extraction and cleanup methods have revived interest in TLC. The combination of these procedures with rigid quality control has created a niche for TLC in laboratories working in compliance with ISO 17025 or GLP. The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture recognized the importance of testing pesticide residues, especially in countries with limited resources. A coordinated research programme (CRP) was initiated for investigating the application of TLC detection methods to complement the instrumental techniques in pesticide residue analysis. An initial technical contract provided proof of the concept and elaborated the basic procedures, including a substantial database of retention factors and minimum detectable quantities of pesticides. To satisfy the demands from the eligible laboratories, two similar projects were started in 1997 and 1998. The titles of the projects were as follows: (i) Validation of Thin-layer Chromatographic Screening Methods for Pesticide Residue Analysis; and (ii) Alternative Methods to Gas and High Performance Liquid Chromatography for Pesticide Residue Analysis in Grain. Scientists from 18 countries participated in the above noted two projects. The major tasks of this programme were to adapt the methods, check the repeatability and reproducibility of Rf values, the minimum detectable quantities (MDQ) and apply the methods for determining various pesticide residues in representative matrices. Furthermore, they have extended the methods to other pesticides and commodities of interest in their countries and validated the methods elaborated. This TECDOC includes the most

  13. Validation of a method for the determination of 120 pesticide residues in apples and cucumbers by LC-MS/MS.

    Science.gov (United States)

    Ramadan, Gouda; Al Jabir, Muna; Alabdulmalik, Najat; Mohammed, Ali

    2016-05-01

    Most countries have clearly defined regulations governing the use of pesticides in agricultural activity. The application of pesticides in agriculture usually leads to a residual amount of these pesticides on food products such as fruit and vegetables. The presence of pesticide residues on these foods destined for human consumption may pose food safety risks to consumers. To protect consumers, national authorities have established maximum limits for pesticide residues in foods. These limits can only be enforced if there are methods available to detect and monitor their concentrations in the applicable food products. To support the enforcement of this legislation, we have developed a multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of 120 pesticide residues in apples and cucumbers which has been validated and implemented in the routine monitoring and surveillance programme for these pesticides. In this method, apple and cucumber samples are extracted using the QuEChERS method (quick, easy, cheap, effective, rugged, and safe) and the extracts were analyzed directly by LC-MS/MS. The mean recoveries at three different concentrations of 0.01 µg/g , 0.05 µg/g, and 0.1 µg/g over the analytical range varied between 70 and 120%. The repeatability of the method expressed as %RSD was less than 20%. The limit of detection (LOD) of the method ranged between 0.0014 and 0.0110 µg/g for apples and between 0.0012 and 0.0075 µg/g for cucumbers. The limit of quantification (LOQ) of the method was 0.01 µg/g for apples and cucumbers. The method has been used for the analysis of over 600 apple and 550 cucumber samples over the past two years. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27443204

  14. Analytical Method Validation of Selected Organochlorine Pesticides in Fortified Rice Using Gas Chromatography with Electron Capture Detector

    Directory of Open Access Journals (Sweden)

    Mutia Kusuma Wardani

    2014-01-01

    Full Text Available Gas chromatography with electron capture detector (GC-ECD has been validated for simultaneous determination of selected organochlorine pesticides namely heptachlor, endosulfan, dieldrin, dan p,p’-dichlorodiphenyltrichloroethane (p,p’-DDT using aldrin as standard internal. Some parameters for analytical method validation were evaluated, i.e. linearity, precision, sensitivity expressed with limit of detection and limit of quantification, and recovery. GC-ECD was linear for determination of these pesticides with r values ≥ 0.99. The values of LOD obtained were 2.50, 2.97, 1.61, and 2.54 ng/mL for heptachlor, endosulphan, dieldrin, and p,p’-DDT, respectively. Furthermore, the relative standard deviation (RSD values obtained for the assessment of analytical precision were lower than those required by Horwitz. Finally, the used GC-ECD method was accurate for determination of these organochlorine psticides in fortified rice samples which were indicated by the acceptable recovery percentages.

  15. Benzimidazole Carbamate Residues in Milk: Detection by SPR Biosensor; using a Modified QuEChERS Method for Extraction

    Science.gov (United States)

    A surface plasmon resonance (SPR) biosensor screening assay was developed and validated to detect 11 benzimidazole carbamate (BZT) veterinary drug residues in milk. The polyclonal antibody used was raised in sheep against a methyl 5 (6)-[(carboxypentyl)-thio]-2-benzimidazole carbamate protein conjug...

  16. Validation and Uncertainty of the method for multiresidue analysis of 35 pesticides in melon using Gas Chromatography Coupled to Quadrupole Mass Spectrometry (GC-QP/MS)

    International Nuclear Information System (INIS)

    QuEChERS method and detection in GC/SQ-MS were validated for the analysis of 35 pesticides in melon. Validation parameters (selectivity, linearity, LOD, LOQ, accuracy and precision) were determined according ABNT NBR 14029:2005. The recoveries rates for all the pesticides studied were from 63% to 117% with relative standard deviation (RSD) lower than 15% in the concentration range of 0.05 – 0.20 mg/kg. The limit of quantification (LOQ) for most compounds were below the MRLs established in Brazil. The combined relative uncertainty (Uc) and expanded uncertainty (Ue) was determined using repetitivity, recovery and calibration curves data for each pesticide

  17. Validation and Uncertainty of the method for multiresidue analysis of 35 pesticides in melon using Gas Chromatography Coupled to Quadrupole Mass Spectrometry (GC-QP/MS)

    Science.gov (United States)

    Milhome, M. A. L.; Sousa, J. S.; Andrade, G. A.; de Castro, R. C.; Lima, L. K.; Lima, C. G.; Nascimento, R. F.

    2015-01-01

    QuEChERS method and detection in GC/SQ-MS were validated for the analysis of 35 pesticides in melon. Validation parameters (selectivity, linearity, LOD, LOQ, accuracy and precision) were determined according ABNT NBR 14029:2005. The recoveries rates for all the pesticides studied were from 63% to 117% with relative standard deviation (RSD) lower than 15% in the concentration range of 0.05 - 0.20 mg/kg. The limit of quantification (LOQ) for most compounds were below the MRLs established in Brazil. The combined relative uncertainty (Uc) and expanded uncertainty (Ue) was determined using repetitivity, recovery and calibration curves data for each pesticide.

  18. Validation of a QuEChERS-based gas chromatographic method for analysis of pesticide residues in Cassia angustifolia (senna).

    Science.gov (United States)

    Tripathy, Vandana; Saha, Ajoy; Patel, Dilipkumar J; Basak, B B; Shah, Paresh G; Kumar, Jitendra

    2016-08-01

    A simple multi-residue method based on modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach was established for the determination of 17 organochlorine (OC), 15 organophosphorous (OP) and 7 synthetic pyrethroid (SP) pesticides in an economically important medicinal plant of India, Senna (Cassia angustifolia), by gas chromatography coupled to electron capture and flame thermionic detectors (GC/ECD/FTD) and confirmation of residues was done on gas chromatograph coupled with mass spectrometry (GC-MS). The developed method was validated by testing the following parameters: linearity, limit of detection (LOD), limit of quantification (LOQ), matrix effect, accuracy-precision and measurement uncertainty; the validation study clearly demonstrated the suitability of the method for its intended application. All pesticides showed good linearity in the range 0.01-1.0 μg mL(-1) for OCs and OPs and 0.05-2.5 μg mL(-1) for SPs with correlation coefficients higher than 0.98. The method gave good recoveries for most of the pesticides (70-120%) with intra-day and inter-day precision < 20% in most of the cases. The limits of detection varied from 0.003 to 0.03 mg kg(-1), and the LOQs were determined as 0.01-0.049 mg kg(-1). The expanded uncertainties were <30%, which was distinctively less than a maximum default value of ±50%. The proposed method was successfully applied to determine pesticide residues in 12 commercial market samples obtained from different locations in India. PMID:27153296

  19. Validation of a QuEChERS-based gas chromatographic method for analysis of pesticide residues in Cassia angustifolia (senna).

    Science.gov (United States)

    Tripathy, Vandana; Saha, Ajoy; Patel, Dilipkumar J; Basak, B B; Shah, Paresh G; Kumar, Jitendra

    2016-08-01

    A simple multi-residue method based on modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach was established for the determination of 17 organochlorine (OC), 15 organophosphorous (OP) and 7 synthetic pyrethroid (SP) pesticides in an economically important medicinal plant of India, Senna (Cassia angustifolia), by gas chromatography coupled to electron capture and flame thermionic detectors (GC/ECD/FTD) and confirmation of residues was done on gas chromatograph coupled with mass spectrometry (GC-MS). The developed method was validated by testing the following parameters: linearity, limit of detection (LOD), limit of quantification (LOQ), matrix effect, accuracy-precision and measurement uncertainty; the validation study clearly demonstrated the suitability of the method for its intended application. All pesticides showed good linearity in the range 0.01-1.0 μg mL(-1) for OCs and OPs and 0.05-2.5 μg mL(-1) for SPs with correlation coefficients higher than 0.98. The method gave good recoveries for most of the pesticides (70-120%) with intra-day and inter-day precision < 20% in most of the cases. The limits of detection varied from 0.003 to 0.03 mg kg(-1), and the LOQs were determined as 0.01-0.049 mg kg(-1). The expanded uncertainties were <30%, which was distinctively less than a maximum default value of ±50%. The proposed method was successfully applied to determine pesticide residues in 12 commercial market samples obtained from different locations in India.

  20. Validation of a methodology multi-residue for the determination of pesticides residuals in strawberry (fragraria spp.) by gas chromatography

    International Nuclear Information System (INIS)

    This study describes the validation of multi-residue analytical methodology for the simultaneous determination of 19 organ chlorine, organophosphorus and organ nitrogen pesticides in strawberry. Pesticides residues were extracted from strawberry samples with ethyl acetate, the extracts were cleaned-up by GPC, the quantitative analysis was carried out by high resolution gas chromatography (GC) with a pulsed splitless injection mode and simultaneous detection by m-ECD and NPD coupled in parallel. The methodology is specific, selective, and accurate and robust the calibration curves in matrix matched analytical standards show linearity over the concentration range of 0.04-5.00 mg/kg with limits of detection and quantitation between 0.007-0.5 mg/kg and 0.01-1.00 mg/kg respectively. The recovery experiments yielding averages between 80-110% for most of the pesticides. The distribution of analyze in the laboratory sample was evaluated and it was found its homogeneity. The methodology was applied in field samples and was mainly found Captan residues below MRL

  1. Organic carbamates in drug design and medicinal chemistry.

    Science.gov (United States)

    Ghosh, Arun K; Brindisi, Margherita

    2015-04-01

    The carbamate group is a key structural motif in many approved drugs and prodrugs. There is an increasing use of carbamates in medicinal chemistry and many derivatives are specifically designed to make drug-target interactions through their carbamate moiety. In this Perspective, we present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of carbamates, and recent applications of carbamates in drug design and medicinal chemistry.

  2. Neurotoxicity of pesticides.

    Science.gov (United States)

    Keifer, Matthew C; Firestone, Jordan

    2007-01-01

    Several pesticides such as organophosphates, carbamates and the organochlorine pesticides directly target nervous tissue as their mechanism of toxicity. In several others, such as the fumigants, the nervous system is affected by toxicological mechanisms that diffusely affect most or all tissues in the body. Both the central and peripheral nervous system are involved in the acute toxidromes of many pesticides resulting in acute short-term effects. There is strong human epidemiological evidence for persistent nervous system damage following acute intoxication with several important pesticide groups such as organophosphates and certain fumigants. However, whether persistent nervous system damage follows chronic low-level exposure to pesticides in adults (particularly organophosphpates), and whether in utero and/or early childhood exposure leads to persistent nervous system damage, is a subject of study at present. Parkinson's Disease, one of the most common chronic central nervous system diseases, has been linked to pesticide exposure in some studies, but other studies have failed to find an association. Several new pesticidal chemicals such as the neo-nicotinoids and fipronil have central nervous system effects, but only case reports are available to date on acute human intoxications with several of these. Little data are yet available on whether long-term effects result from these chemicals. Several ongoing or recently completed studies should add valuable insight into the effects of pesticides on the human nervous system particularly the effect of low-dose, chronic exposure both in adults and children.

  3. 液相色谱-串联质谱法测定植物源性食品中16种氨基甲酸酯类农药及其代谢物%Determination of 16 carbamate pesticides and metabolite residues in plant-derived foodstuffs by high pressure liquid chromatography-tandem mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    王敬; 陈瑞春; 郭春海; 窦彩云

    2013-01-01

    目的:建立液相色谱-串联质谱法测定植物源性食品中16种氨基甲酸酯类农药及其代谢物(涕灭威、涕灭威亚砜、涕灭威砜、灭害威、恶虫威、甲萘威、克百威、乙霉威、仲丁威、茚虫威、异丙威、灭多威、速灭威、杀线威、抗蚜威和残杀威)残留量的方法。方法样品用0.1%冰醋酸-乙腈提取,提取液经过滤、浓缩后用石墨化炭黑/氨基固相萃取柱净化,采用多反应监测(multi-reaction monitoring, MRM)正离子扫描模式进行准确的定性和定量分析。结果16种氨基甲酸酯类农药在5~500 ng/mL浓度范围内均呈良好线性。16种农药在苹果、菠菜、山药、大米、大豆和生姜6种基质中的检出限和定量下限为2.0µg/kg和5.0µg/kg,在低、中、高3个水平的加标回收率为71.0%~108.0%之间, RSDs (relative standard deviations)为2.03%~11.30%。结论该方法简单快速,其灵敏度、准确度和精密度均能满足农药残留分析的要求。%Objective To establish a high pressure liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for determination 16 kinds of carbamate pesticides and their metabolites (aldicarb, al-dicarb-sulfoxide, aldicarb-sulfone, aminocarb, bendicarb, carbaryl, carbofuran, diethofencarb, fenobucarb, in-doxacarb, isoprocarb, methomyl, metolcarb, oxamyl, pirimicarb and propoxur) in plant-derived foodstuffs. Methods Samples were extracted with 0.1%formic acid-acetonitrile solution. After concentrated, the solution was cleaned up with solid-phase extraction (SPE) column of envi-Carb/NH2, the mode of multi-reaction moni-toring positive ion scanning was adopted for both the quantitative and qualitative analyses. Results Calibra-tion curves showed a good linearity over the range of 5~500 ng/mL. The limits of detection (LOD) were 2.0 µg/kg and the limits of quantification (LOQ) were 5.0 µg/kg for all the 16 pesticides spiked in apple, spinach, Chinese yam, rice, soybean and ginger

  4. Pesticides and inner-city children: exposures, risks, and prevention.

    OpenAIRE

    Landrigan, P J; Claudio, L; Markowitz, S B; Berkowitz, G S; Brenner, B L; H. Romero; Wetmur, J G; Matte, T D; Gore, A.C.; Godbold, J H; Wolff, M S

    1999-01-01

    Six million children live in poverty in America's inner cities. These children are at high risk of exposure to pesticides that are used extensively in urban schools, homes, and day-care centers for control of roaches, rats, and other vermin. The organophosphate insecticide chlorpyrifos and certain pyrethroids are the registered pesticides most heavily applied in cities. Illegal street pesticides are also in use, including tres pasitos (a carbamate), tiza china, and methyl parathion. In New Yo...

  5. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization

    International Nuclear Information System (INIS)

    Highlights: • Applicability of GC-(APCI)QTOF MS as new tool for wide-scope screening of pesticides in fruits and vegetables demonstrated. • Validation of screening method according to SANCO/12571/2013. • Detection of the pesticides based on the presence of M+·/MH+ in most cases. • Screening detection limit 0.01 mg kg−1 for 77% of the pesticides investigated. • Successful identification at 0.01 mg kg−1 for 70% of the pesticides/matrix combinations. - Abstract: A wide-scope screening method was developed for the detection of pesticides in fruit and vegetables. The method was based on gas chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer with an atmospheric pressure chemical ionization source (GC-(APCI)QTOF MS). A non-target acquisition was performed through two alternating scan events: one at low collision energy and another at a higher collision energy ramp (MSE). In this way, both protonated molecule and/or molecular ion together with fragment ions were obtained in a single run. Validation was performed according to SANCO/12571/2013 by analysing 20 samples (10 different commodities in duplicate), fortified with a test set of 132 pesticides at 0.01, 0.05 and 0.20 mg kg−1. For screening, the detection was based on one diagnostic ion (in most cases the protonated molecule). Overall, at the 0.01 mg kg−1 level, 89% of the 2620 fortifications made were detected. The screening detection limit for individual pesticides was 0.01 mg kg−1 for 77% of the pesticides investigated. The possibilities for identification according to the SANCO criteria, requiring two ions with a mass accuracy ≤±5 ppm and an ion-ratio deviation ≤±30%, were investigated. At the 0.01 mg kg−1 level, identification was possible for 70% of the pesticides detected during screening. This increased to 87% and 93% at the 0.05 and 0.20 mg kg−1 level, respectively. Insufficient sensitivity for the second ion was the main reason for the inability to

  6. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization

    Energy Technology Data Exchange (ETDEWEB)

    Portolés, T. [Research Institute for Pesticides and Water, University Jaume I, 12071 Castellón (Spain); RIKILT Institute of Food Safety, Wageningen University and Research Centre, Akkermaalsbos 2, 6708 WB Wageningen (Netherlands); Mol, J.G.J. [RIKILT Institute of Food Safety, Wageningen University and Research Centre, Akkermaalsbos 2, 6708 WB Wageningen (Netherlands); Sancho, J.V.; López, Francisco J. [Research Institute for Pesticides and Water, University Jaume I, 12071 Castellón (Spain); Hernández, F., E-mail: hernandf@uji.es [Research Institute for Pesticides and Water, University Jaume I, 12071 Castellón (Spain)

    2014-08-01

    Highlights: • Applicability of GC-(APCI)QTOF MS as new tool for wide-scope screening of pesticides in fruits and vegetables demonstrated. • Validation of screening method according to SANCO/12571/2013. • Detection of the pesticides based on the presence of M+·/MH+ in most cases. • Screening detection limit 0.01 mg kg{sup −1} for 77% of the pesticides investigated. • Successful identification at 0.01 mg kg{sup −1} for 70% of the pesticides/matrix combinations. - Abstract: A wide-scope screening method was developed for the detection of pesticides in fruit and vegetables. The method was based on gas chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer with an atmospheric pressure chemical ionization source (GC-(APCI)QTOF MS). A non-target acquisition was performed through two alternating scan events: one at low collision energy and another at a higher collision energy ramp (MS{sup E}). In this way, both protonated molecule and/or molecular ion together with fragment ions were obtained in a single run. Validation was performed according to SANCO/12571/2013 by analysing 20 samples (10 different commodities in duplicate), fortified with a test set of 132 pesticides at 0.01, 0.05 and 0.20 mg kg{sup −1}. For screening, the detection was based on one diagnostic ion (in most cases the protonated molecule). Overall, at the 0.01 mg kg{sup −1} level, 89% of the 2620 fortifications made were detected. The screening detection limit for individual pesticides was 0.01 mg kg{sup −1} for 77% of the pesticides investigated. The possibilities for identification according to the SANCO criteria, requiring two ions with a mass accuracy ≤±5 ppm and an ion-ratio deviation ≤±30%, were investigated. At the 0.01 mg kg{sup −1} level, identification was possible for 70% of the pesticides detected during screening. This increased to 87% and 93% at the 0.05 and 0.20 mg kg{sup −1} level, respectively. Insufficient sensitivity for the second

  7. [Neurotoxicology of pesticides].

    Science.gov (United States)

    Ichikawa, Hiroo

    2015-01-01

    Pesticides have been used for many years for preventing, destroying, repelling, or mitigating pests such as insects, rodents, and weeds. However, most pesticides are not completely specific for pests and can also induce damage to the human nervous system. In particular, insecticides often directly targets the nervous system by affecting major targets such as the neuro-transmitter metabolism, neuronal receptors, and ion channels; acetylcholine (ACh) esterase for organo-phosphates and carbamates, nicotinic ACh receptor for neonicotinoids, γ-aminobutyric acid receptors/chloride channels for organochlorides and fipronil, and voltage-gated sodium channel for pyrethroids. Additional targets include sites in the sodium channels, glutamate-gated chloride channels, and octopamine and ryanodine receptors. Several pesticides also produce adverse neurological effects indirectly by disrupting the general cellular mechanisms that support the high metabolic activity of the nervous system. Nowadays, more potent pesticides are being developed as replacements for the older, harmful ones. Pesticide neurotoxicity in humans may involve the central or peripheral nervous system or both and may induce typical neuronal damage in case of acute poisoning even by new agents. However, whether effect of exposure to pesticides at below acute-poisoning threshold level remains unclear. Moreover, neurotoxicology for behavioral and higher-brain function remains an unresolved and a challenging problem.

  8. Carbamic acid and carbamate formation in NH{3}:CO{2} ices - UV irradiation versus thermal processes

    Science.gov (United States)

    Bossa, J. B.; Theulé, P.; Duvernay, F.; Borget, F.; Chiavassa, T.

    2008-12-01

    Context: We study carbamic acid [ NH{2}COOH] and ammonium carbamate [ NH{2}COO-] [ NH{4}+] formation in interstellar ice analogs. Aims: We demonstrate how carbamic acid [ NH{2}COOH] and ammonium carbamate [ NH{2}COO-] [ NH{4}+] can be formed from both thermal reactions and energetic photons in an NH{3}:CO{2} ice mixture. Methods: Infrared and mass spectroscopy are used to monitor NH{3}:CO{2} ice mixture evolution during both warming and VUV photon irradiation. Results: Carbamic acid and ammonium carbamate can be produced thermally in a 1:1 ratio from NH{3} and CO{2} above 80 K. They can be also formed in a 28:1 ratio by less efficient processes such as energetic photons. Our study and its results provide fresh insight into carbamic acid formation in interstellar ices. Conclusions: We demonstrate that care is required to separate irradiation-induced reactivity from purely thermal reactivity in ices in which ammonia and carbon dioxide are both present. From an interstellar chemistry point of view, carbamic acid and ammonium carbamate are readily produced from the ice mantle of a typical interstellar grain and should therefore be a detectable species in molecular clouds.

  9. Fenugreek hydrogel–agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection

    Energy Technology Data Exchange (ETDEWEB)

    Kestwal, Rakesh Mohan; Bagal-Kestwal, Dipali; Chiang, Been-Huang, E-mail: bhchiang@ntu.edu.tw

    2015-07-30

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel–agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10–20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel–agarose–acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. - Highlights: • Acetylcholinesterase (AChE) dip-strip biosensor fabricated to detect carbamates. • AChE entrapped in fenugreek hydrogel–agarose matrix with gold nanoparticles (GNPs). • High enzyme retention efficiency (92%) and shelf life (half-life, 55 days). • Detection limits of carbofuran, oxamyl and methomyl: 2, 21 and 113 nM. • The biosensor had good testing capabilities to detect carbamates in food samples.

  10. Fenugreek hydrogel–agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection

    International Nuclear Information System (INIS)

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel–agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10–20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel–agarose–acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. - Highlights: • Acetylcholinesterase (AChE) dip-strip biosensor fabricated to detect carbamates. • AChE entrapped in fenugreek hydrogel–agarose matrix with gold nanoparticles (GNPs). • High enzyme retention efficiency (92%) and shelf life (half-life, 55 days). • Detection limits of carbofuran, oxamyl and methomyl: 2, 21 and 113 nM. • The biosensor had good testing capabilities to detect carbamates in food samples

  11. Detection of benzimidazole carbamates and amino metabolites in liver by surface plasmon resonance-biosensor

    Science.gov (United States)

    Two surface plasmon resonance (SPR) biosensor screening assays were developed and validated to detect 11 benzimidazole carbamate (BZT) and four amino-benzimidazole veterinary drug residues in liver tissue. The assays used polyclonal antibodies, raised in sheep, to detect BZTs and amino-benzimidazole...

  12. Within-laboratory validation of a multiresidue method for the analysis of 98 pesticides in mango by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Fleury Filho, N; Nascimento, C A; Faria, E O; Cruvinel, A R; Oliveira, J M

    2012-01-01

    A within-laboratory validation procedure for a selective and sensitive method for the simultaneous determination of 98 pesticide residues in mango is presented. QuEChERS extraction was adapted to laboratory conditions. Mango samples (10 g) mixed with sodium sulfate (4 g) and sodium acetate (1 g) were extracted with acetonitrile/acetic acid (99/1 v/v), cleaned using dispersive solids, and subsequently identified and quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Pesticides were separated on a reversed-phase column using a gradient elution in conjunction with positive-mode electrospray ionisation. The analytical performance of the method was demonstrated by analysis of spiked mango samples at three concentration levels (0.01, 0.05 and 0.1 mg kg(-1)) for 3 different days, and the analysis was performed by three analysts. Calibration curves were statistically acceptable by the ordinary last-square method (OLSM), with a regression coefficient above 0.98 for all analytes. The method accuracy (n = 18) was between 80% and 110%, and precisions were below 20% for 95% of the analytes. The method uncertainty at the LOQ was evaluated considering the uncertainty associated with the calibration curve and the uncertainty associated with the method precision. The validation data for all pesticides were in accordance with Brazilian and European guidelines for pesticide residue analysis. PMID:22014095

  13. Types of pesticides and determination of their residues

    International Nuclear Information System (INIS)

    The pesticide is any material or component used to protect from pests. Its toxic effect is related to the chemical structure, which can be divided into 3 types : 1- Metal pesticides : Sulphur, cupper, zinc, mercury; 2- Vegetal pesticides : advanced and less toxic to the general health; 3- Synthetic organo pesticides : organo chlorine, organophosphorous, carbamate and pyrethroids. Pesticides in the soil undergo biological dissociation according to their concentration and chemical structure. High concentration of the pesticides in the soil may lead to fertility decrease due to destruction of micro-organisms by the pesticides. Many methods are used to analyze the residues of pesticides in plant or soil : 1- Chromatographic methods : Gas chromatography, gas liquid chromatography and high performance liquid chromatography; 2- Spectroscopy methods : spectrophotometer and mass spectrometer; 3- Isotopic methods : based on tracers technique which is the most sensitive and accurate method and can estimate minor amounts of the pesticides. (author)

  14. Fenugreek hydrogel-agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection.

    Science.gov (United States)

    Kestwal, Rakesh Mohan; Bagal-Kestwal, Dipali; Chiang, Been-Huang

    2015-07-30

    A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel-agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10-20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel-agarose-acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples. PMID:26320646

  15. A PHYSIOLOGICALLY BASED PHARMACOKINETIC/PHARMACODYNAMIC (PBPK/PD) MODEL FOR ESTIMATION OF CUMULATIVE RISK FROM EXPOSURE TO THREE N-METHYL CARBAMATES: CARBARYL, ALDICARB, AND CARBOFURAN

    Science.gov (United States)

    A physiologically-based pharmacokinetic (PBPK) model for a mixture of N-methyl carbamate pesticides was developed based on single chemical models. The model was used to compare urinary metabolite concentrations to levels from National Health and Nutrition Examination Survey (NHA...

  16. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization.

    Science.gov (United States)

    Portolés, T; Mol, J G J; Sancho, J V; López, Francisco J; Hernández, F

    2014-08-01

    A wide-scope screening method was developed for the detection of pesticides in fruit and vegetables. The method was based on gas chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer with an atmospheric pressure chemical ionization source (GC-(APCI)QTOF MS). A non-target acquisition was performed through two alternating scan events: one at low collision energy and another at a higher collision energy ramp (MS(E)). In this way, both protonated molecule and/or molecular ion together with fragment ions were obtained in a single run. Validation was performed according to SANCO/12571/2013 by analysing 20 samples (10 different commodities in duplicate), fortified with a test set of 132 pesticides at 0.01, 0.05 and 0.20mg kg(-1). For screening, the detection was based on one diagnostic ion (in most cases the protonated molecule). Overall, at the 0.01mg kg(-1) level, 89% of the 2620 fortifications made were detected. The screening detection limit for individual pesticides was 0.01mg kg(-1) for 77% of the pesticides investigated. The possibilities for identification according to the SANCO criteria, requiring two ions with a mass accuracy ≤±5ppm and an ion-ratio deviation ≤±30%, were investigated. At the 0.01mg kg(-1) level, identification was possible for 70% of the pesticides detected during screening. This increased to 87% and 93% at the 0.05 and 0.20mg kg(-1) level, respectively. Insufficient sensitivity for the second ion was the main reason for the inability to identify detected pesticides, followed by deviations in mass accuracy and ion ratios.

  17. Fluorimetric Determination of Carbamate Pesticides in Host-Guest Complexes

    Directory of Open Access Journals (Sweden)

    Alicia Viviana Veglia

    2000-03-01

    Full Text Available From the effect of β-cyclodextrin and hydroxypropyl-β-cyclodextrin on the UVvisible and fluorescence spectra of carbaryl and carbofuran, the values of association constants were determined. The ratio of the fluorescence quantum yields for the bound and free substrates indicated an enhanced fluorimetric method of detection.

  18. Fluorimetric Determination of Carbamate Pesticides in Host-Guest Complexes

    OpenAIRE

    Alicia Viviana Veglia

    2000-01-01

    From the effect of β-cyclodextrin and hydroxypropyl-β-cyclodextrin on the UVvisible and fluorescence spectra of carbaryl and carbofuran, the values of association constants were determined. The ratio of the fluorescence quantum yields for the bound and free substrates indicated an enhanced fluorimetric method of detection.

  19. 40 CFR 721.2025 - Substituted phenylimino carbamate derivative.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenylimino carbamate... Specific Chemical Substances § 721.2025 Substituted phenylimino carbamate derivative. (a) Chemical... as a substituted phenylimino carbamate derivative (PMN P-91-487) is subject to reporting under...

  20. 21 CFR 520.434 - Chlorphenesin carbamate tablets.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Chlorphenesin carbamate tablets. 520.434 Section... Chlorphenesin carbamate tablets. (a) Specifications. Each tablet contains 400 milligrams of chlorphenesin carbamate. (b) Sponsor. See No. 000009 in § 510.600(c) of this chapter. (c) Conditions of use in...

  1. Pesticide residue determination in vegetables from western China applying gas chromatography with mass spectrometry.

    Science.gov (United States)

    Qin, Guofu; Zou, Keting; Li, Yongbo; Chen, Yan; He, Fengrui; Ding, Guirong

    2016-09-01

    In this study,an effort has been made to evaluate the pesticide residues in vegetables from western China. Fifty-one pesticides, including organophosphorus, organochlorine, carbamate and pyrethroid, were detected in 369 commonly used vegetables by GC-MS. Concentrations of organophosphorus pesticides were detected ranging from 0.0008 to 18.8200 mg/kg, among which organophosphorus pesticide concentrations exceeded their maximum residue levels (MRLs) in five samples. Carbamate and organochlorine pesticides were determined to have concentrations in the range of 0.0012-0.7928 mg/kg. The residual concentrations of carbamate pesticides in six samples and organochlorine pesticides in four samples exceeded their MRLs. The residual concentrations of five pyrethroid pesticides were within the range of 0.0016-6.0827 mg/kg and the pyrethroid residues in two samples exceeded their MRLs. The results revealed that pesticide residues in 70.73% of the vegetables samples were not detected, while in the rest of vegetables there were one or more pesticide residues and some even exceeded their MRLs, which would threaten the health of consumers. Our work provides significant information for the food safety regulations to control the excessive use of some pesticides on those kinds of vegetables from western China. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26864471

  2. Using phylogenetic information and chemical properties to predict species tolerances to pesticides.

    Science.gov (United States)

    Guénard, Guillaume; Carsten von der Ohe, Peter; Carlisle Walker, Steven; Lek, Sovan; Legendre, Pierre

    2014-08-22

    Direct estimation of species' tolerance to pesticides and other toxic organic substances is a combinatorial problem, because of the large number of species-substance pairs. We propose a statistical modelling approach to predict tolerances associated with untested species-substance pairs, by using models fitted to tested pairs. This approach is based on the phylogeny of species and physico-chemical descriptors of pesticides, with both kinds of information combined in a bilinear model. This bilinear modelling approach predicts tolerance in untested species-compound pairs based on the facts that closely related species often respond similarly to toxic compounds and that chemically similar compounds often have similar toxic effects. The three tolerance models (median lethal concentration after 96 h) used up to 25 aquatic animal species and up to nine pesticides (organochlorines, organophosphates and carbamates). Phylogeny was estimated using DNA sequences, while the pesticides were described by their mode of toxic action and their octanol-water partition coefficients. The models explained 77-84% of the among-species variation in tolerance (log10 LC50). In cross-validation, 84-87% of the predicted tolerances for individual species were within a factor of 10 of the observed values. The approach can also be used to model other species response to multivariate stress factors.

  3. Antimicrobial Pesticides

    Science.gov (United States)

    ... US EPA US Environmental Protection Agency Search Search Pesticides Share Facebook Twitter Google+ Pinterest Contact Us You are here: EPA Home » Pesticides » Antimicrobial Pesticides Antimicrobial Pesticides News and Highlights Disinfection Hierarchy Workshop - October 7 ...

  4. High-performance liquid chromatography multiresidue method for the determination of N-methyl carbamates in fruit and vegetable juices.

    Science.gov (United States)

    Sánchez-Brunete, Consuelo; Albero, Beatriz; Tadeo, José Luis

    2004-11-01

    A rapid multiresidue method has been developed for the analysis of N-methylcarbamate insecticides (oxamyl, methomyl, propoxur, carbofuran, carbaryl, and methiocarb) in fruit and vegetable juices. The method is based on the adsorption of the N-methyl carbamates in Florisil and the subsequent extraction of pesticides using a low volume of acetone. Residue levels in juice were determined by reversed-phase high-performance liquid chromatography with fluorescence detection after postcolumn derivatization. The separation of carbamates is performed on a C8 column with water-methanol as mobile phase. Recovery studies were performed at 500-, 100-, and 10-ng/ml fortification levels, and average recoveries obtained for carbamates ranged from 79 to 109%, with relative standard deviations between 1.4 and 9.9%. The method was found to be linear over the range assayed from 10 to 1,000 ng/ml, and the detection limits for carbamates varied from 0.8 to 1.9 ng/ml. PMID:15553643

  5. Validation of a multi-residue method for the determination of residuals pesticides in cabbage (Brassica Oleracea var. Capitata) for gases chromatography

    International Nuclear Information System (INIS)

    This study describes the validation of a multi-residue method for the determination of most used organo chlorine, organophosphorus and organonitrogen pesticides in cabbage in the Cundinamarca Department (Colombia). The extraction process includes blending of small sample quantity with ethyl acetate in presence of Na2SO4 and NaHCO3, filtration and concentration. The clean up steps include GPC and mini-column chromatography using silica gel. Final determination was carried out by gas chromatography with: pulsed splitless injection, HP-5 capillary column, and a parallel detection system with micro electron capture detection (μ - ECD) and Nitrogen-Phosphorus Detection (NPD). The methodology is specific, selective, accurate and robust. Recovery values of majority of pesticides were in the range 70-120% at spiking levels ranging 0.05-10.73 mg/kg. Limits of detection were less than 0.10 mg/kg for most of the studied compounds. The distribution of the analyses in the laboratory sample was evaluated and it was found its homogeneity. The evaluation of pesticide residues was made in a specific area of municipality of Madrid-Cundinamarca, (Colombia). No residues of the studied analyses were founded

  6. Effect of in vitro estrogenic pesticides on human oestrogen receptor α and β mRNA levels

    DEFF Research Database (Denmark)

    Theander Grünfeld, Heidi; Bonefeld-Jørgensen, Eva Cecilie

    2004-01-01

    , endosulfan, dieldrin, and tolchlofos-methyl, whereas no significant effect of the carbamate pesticides on the ERβ mRNA level was observed. This study demonstrated that organochlor and organophosphorous pesticides possess the ability to interfere with the ERα and ERβ mRNA steady state levels....

  7. AN ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) TESTING OF ENZYMATIC TEST KITS FOR WARFARE AGENTS AND PESTICIDES IN DRINKING WATER

    Science.gov (United States)

    Enzymatic test kits, generally designed to be handheld and portable, detect the presence of chemical agents, carbamate pesticides, and/or organophosphate pesticides by relying on the reaction of the cholinesterase enzyme. Under normal conditions, the enzyme reacts as expected wi...

  8. Method validation for the analysis of 169 pesticides in soya grain, without clean up, by liquid chromatography-tandem mass spectrometry using positive and negative electrospray ionization.

    Science.gov (United States)

    Pizzutti, Ionara R; de Kok, André; Zanella, Renato; Adaime, Martha B; Hiemstra, Maurice; Wickert, Cristine; Prestes, Osmar D

    2007-02-23

    Part of a comprehensive study on the comparison of different extraction methods, GC-MS(/MS) and LC-MS/MS detection methods and modes, for the analysis of soya samples is described in this paper. The validation of an acetone-based extraction method for analysis of 169 pesticides in soya, using LC-MS/MS positive and negative electrospray ionisation (ESI) mode, is reported. Samples (5 g) were soaked with 10 g water and subsequently extracted with 100 mL of a mixture of acetone, dichloromethane and light petroleum (1:1:1), in the presence of 15 g anhydrous sodium sulphate. After centrifugation, aliquots of the extract were evaporated and reconstituted in 1.0 mL of methanol, before direct injection of the final extract (corresponding with 0.05 g soya mL(-1)) into the LC-MS/MS system. Linearity, r(2) of calibration curves, instrument limit of detection/quantitation (LOD/LOQ) and matrix effect were evaluated, based on seven concentrations measured in 6-fold. Good linearity (at least r(2)> or =0.99) of the calibration curves was obtained over the range from 0.1 or 0.25 to 10.0 ng mL(-1), corresponding with pesticide concentrations in soya bean extract of 2 or 5-200 microg kg(-1). Instrument LOD values generally were 0.1 or 0.25 ng mL(-1). Matrix effects were negligible for approximately 90% of the pesticides. The accuracy, precision and method LOQ were determined via recovery experiments, spiking soya at 10, 50, 100 microg kg(-1), six replicates per level. In both ESI modes, method LOQ values were mostly 10 or 50 microg kg(-1) and more than 70% of pesticides analysed by each mode met the acceptability criteria of recovery (70-120%) and RSD (soya, without cleanup.

  9. Modification and re-validation of the ethyl acetate-based multi-residue method for pesticides in produce

    NARCIS (Netherlands)

    Mol, H.G.J.; Rooseboom, A.; Dam, R. van; Roding, M.; Arondeus, K.; Sunarto, S.

    2007-01-01

    The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary-secondary amine and graphitized carbon black) and large-volume (20 μL) injecti

  10. Modification and re-validation of the ethyl acetate-based multi-residue method for pesticides in produce

    NARCIS (Netherlands)

    Mol, J.G.J.; Rooseboom, A.; Dam, van R.; Roding, M.; Arondeus, K.; Sunarto, S.

    2007-01-01

    The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary¿secondary amine and graphitized carbon black) and large-volume (20 ¿L) injecti

  11. Multiresidue analysis of 36 pesticides in soil using a modified quick, easy, cheap, effective, rugged, and safe method by liquid chromatography with tandem quadruple linear ion trap mass spectrometry.

    Science.gov (United States)

    Feng, Xue; He, Zeying; Wang, Lu; Peng, Yi; Luo, Ming; Liu, Xiaowei

    2015-09-01

    A new method for simultaneous determination of 36 pesticides, including 15 organophosphorus, six carbamate, and some other pesticides in soil was developed by liquid chromatography with tandem quadruple linear ion trap mass spectrometry. The extraction and clean-up steps were optimized based on the quick, easy, cheap, effective, rugged, and safe method. The data were acquired in multiple reaction monitoring mode combined with enhanced product ion to increase confidence of the analytical results. Validation experiments were performed in soil samples. The average recoveries of pesticides at four spiking levels (1, 5, 50, and 100 μg/kg) ranged from 63 to 126% with relative standard deviation below 20%. The limits of detection of pesticides were 0.04-0.8 μg/kg, and the limits of quantification were 0.1-2.6 μg/kg. The correlation coefficients (r(2) ) were higher than 0.990 in the linearity range of 0.5-200 μg/L for most of the pesticides. The method allowed for the analysis of the target pesticides in the lower μg/kg concentration range. The optimized method was then applied to the test of real soil samples obtained from several areas in China, confirming the feasibility of the method.

  12. Determination of seventeen polar/thermolabile pesticides in apples and apricots by liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Zrostlíková, Jitka; Hajslová, Jana; Kovalczuk, Tomás; Stĕpán, Radim; Poustka, Jan

    2003-01-01

    A simple liquid chromatography/mass spectrometry (LC/MS) approach for the determination of widely used representatives of polar/thermolabile pesticides in fruits was developed and validated. The group of pesticides comprised benzimidazoles and azoles (carbendazim, thiabendazole, imazalil, propiconazole, prochloraz, epoxiconazole, flusilazole, tebuconazole, bitertanol); N-methylcarbamates (carbaryl, carbofuran, methiocarb); and phenylureas and benzoylphenylureas (linuron, diflubenzuron, triflumuron, teflubenzuron, flufenoxuron). Matrixes (apple, apricot) were extracted with acetonitrile and crude extracts were cleaned up by solid-phase extraction (SPE) using either mixed cation exchange or hydrophilic lipophilic balance cartridges. LC separation of pesticides was performed on a reversed-phase column, Discovery C18. Electrospray ionization and ion trap MS/MS detection were applied. For most pesticides, overall recoveries ranged from 75 to 122%, and repeatability (as relative standard deviation) from 5 repetitive determinations of recovery ranged from 3 to 21%. Carbofuran was the only compound for which recovery was not satisfactory due to its loss in the SPE cleanup step. Limits of detection were 0.1-3 microg/kg for benzimidazole and azole fungicides and carbamate insecticides. For urea insecticides, detection limits were slightly higher (3-10 microg/kg). PMID:12852583

  13. Vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction for the determination of carbamates in juices by micellar electrokinetic chromatography tandem mass spectrometry.

    Science.gov (United States)

    Moreno-González, David; Huertas-Pérez, José F; García-Campaña, Ana M; Gámiz-Gracia, Laura

    2015-07-01

    A new method based on vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction has been developed for the extraction of carbamate pesticides in juice samples prior to their determination by micellar electrokinetic chromatography coupled to tandem mass spectrometry. This sample treatment allowed the satisfactory extraction and the extract clean-up of 25 carbamates from different fruit and vegetal juices (banana, tomato, and peach). In this study, the addition of ammonium perfluorooctanoate in the aqueous sample in combination with vortex agitation, provided very clean extracts with short extraction times. Under optimized conditions, recoveries of the proposed method for these pesticides from fortified juice samples ranged from 81% to 104%, with relative standard deviations lower than 15%. Limits of quantification were between 2.3µgkg(-)(1) and 4.7µgkg(-)(1), showing the high sensitivity of this fast and simple method. PMID:25882424

  14. Vinyl carbamate epoxide, a major strong electrophilic, mutagenic and carcinogenic metabolite of vinyl carbamate and ethyl carbamate (urethane).

    Science.gov (United States)

    Park, K K; Liem, A; Stewart, B C; Miller, J A

    1993-03-01

    Vinyl carbamate epoxide (VCO) was found to possess strong electrophilic, mutagenic and carcinogenic activities. It reacted with water at 37 degrees C and pH 7.4 (phosphate buffer) to form glycolaldehyde and several related reducing compounds; none of these products were mutagenic for Salmonella typhimurium TA1535. Under these conditions VCO had a half-life (determined chemically and mutagenically) of approximately 10.5 min. This half-life was progressively lowered by increasing concentrations of chloride ion (liver, serum and isotonic levels). This ion reacted with VCO to form chloroacetaldehyde. VCO also reacted with other nucleophiles such as glutathione, DNA and its constituent guanine and adenine bases. The purine adducts formed by VCO in DNA in vitro and in vivo were released by weak acid treatment and consisted of 7-(2'-oxoethyl)guanine and N2,3-ethenoguanine as major products with 1,N6-ethenoadenine as a minor product. VCO was a strong direct mutagen in Salmonella typhimurium TA1535 and TA100 but was only weakly active in the TA98 mutant. VCO was a stronger initiator of carcinogenesis in the skin of CD-1 mice and in the liver of infant male B6C3F1 mice than its metabolic precursors vinyl carbamate (VC) and ethyl carbamate (EC). Unlike VC and EC, VCO was a strong complete carcinogen in the skin of CD-1 mice and induced papillomas and carcinomas following repetitive administration of sub-ulcerogenic doses. VCO also exhibited some carcinogenic activity in the lungs of mice and in the s.c. and mammary tissue of female Sprague-Dawley rats. These data and those from other recent studies support the conclusion that VCO is a major strong electrophilic, mutagenic and carcinogenic metabolite of EC and VC in the mouse. PMID:8453720

  15. Development of biofilters to treat the pesticides wastes from spraying applications.

    Science.gov (United States)

    Pigeon, O; de Vleeschouwer, C; Cors, F; Weickmans, B; de Ryckel, B; Pussemier, L; Debongnie, Ph; Culot, M

    2005-01-01

    5 classical tracer pesticides but also for other chemical classes of herbicides (sulfonylurea, aryloxyalcanoic acids, chloroacetanilides), insecticides (pyrethroids, carbamates) and fungicides (dicarboximides, phenylamides, triazoles and strobilurines). To monitor these pesticides in elutes and substrates, two analytical methods were developed, optimised and validated : the first one by Gas Chromatography with Mass Spectrometry Detection (GC-MS), and the second one by High Performance Liquid Chromatography with UV Diode Array Detection (HPLC-DAD). The micro-organisms activity in the substrate was also measured in some situations.

  16. Estimation of uncertainty from method validation data: Application to a reverse-phase high-performance liquid chromatography method for the determination of amino acids in gelatin using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate reagent.

    Science.gov (United States)

    Azilawati, M I; Dzulkifly, M H; Jamilah, B; Shuhaimi, M; Amin, I

    2016-09-10

    A detailed procedure for estimating uncertainty according to the Laboratory of Government Chemists/Valid Analytical Measurement (LGC/VAM) protocol for determination of 18 amino acids in gelatin is proposed. The expanded uncertainty was estimated using mainly the method validation data (precision and trueness). Other sources of uncertainties were contributed by components in standard preparation measurements. The method scope covered a single matrix (gelatin) under a wide range of analyte concentrations. The uncertainty of method precision, μ(P) was 0.0237-0.1128pmolμl(-1) in which hydroxyproline and histidine represented the lowest and highest values of uncertainties, respectively. Proline and phenylalanine represented the lowest and highest uncertainties value for method recovery, μ(R) that was estimated within 0.0064-0.0995pmolμl(-1). The uncertainties from other sources, μ(Std) were 0.0325, 0.0428 and 0.0413pmolμl(-1) that were contributed by hydroxyproline, other amino acids and cystine, respectively. Hydroxyproline and phenylalanine represented the lowest and highest values of expanded uncertainty, U(y) that were determined at 0.0949 and 0.2473pmolμl(-1), respectively. The data were accurately defined and fulfill the technical requirements of ISO 17025:2005. PMID:27454091

  17. Chemoselective Synthesis of Carbamates using CO2 as Carbon Source.

    Science.gov (United States)

    Riemer, Daniel; Hirapara, Pradipbhai; Das, Shoubhik

    2016-08-01

    Synthesis of carbamates directly from amines using CO2 as the carbon source is a straightforward and sustainable approach. Herein, we describe a highly effective and chemoselective methodology for the synthesis of carbamates at room temperature and atmospheric pressure. This methodology can also be applied to protect the amino group in amino acids and peptides, and also to synthesize important pharmaceuticals. PMID:27376902

  18. 76 FR 34200 - Land Disposal Restrictions: Revision of the Treatment Standards for Carbamate Wastes

    Science.gov (United States)

    2011-06-13

    ... Standards for Carbamate Wastes AGENCY: Environmental Protection Agency. ACTION: Proposed rule. SUMMARY: The...) treatment standards for hazardous wastes from the production of carbamates and carbamate commercial chemical... carbamate wastes must be treated to meet numeric concentration limits before they can be land...

  19. Method validation for 243 pesticides and environmental contaminants in meats and poultry by tandem mass spectrometry coupled to low-pressure gas chromatography and ultra high-performance liquid chromatography

    Science.gov (United States)

    An easy and reliable high-throughput analysis method was developed and validated for 192 diverse pesticides and 51 environmental contaminants (13 PCB congeners, 14 PAHs, 7 PBDE congeners, and 17 novel flame retardants) in cattle, swine, and poultry muscle. Sample preparation was based on the “quick,...

  20. QuEChERS GC-MS validation and monitoring of pesticide residues in different foods in the tomato classification group.

    Science.gov (United States)

    Ramírez Restrepo, Andrés; Gallo Ortiz, Andrés Fernando; Hoyos Ossa, Duvan Esteban; Peñuela Mesa, Gustavo Antonio

    2014-09-01

    The objective of this study was to validate (SANCO/12495/2011 and NTC-ISO/IEC 17025) multi-residue multi-class methods using QuEChERS sample preparation and GC-MS for the analysis of regulated pesticides in tomatoes (Solanum lycopersicum), tamarillos (Solanum betaceum) and goldenberries (Physalis peruviana). These Latin American products are representative and widely produced in Antioquia (Colombia). Sample preparation followed the UNE-EN 15662 method (150 mg MgSO4, 25mg primary secondary amines and 25mg of octadecylsiloxane for cleanup; graphitized carbon black was added for tomatoes). Extracts were injected using a programmed temperature-vaporizing injector. The residues were validated over a range from 0.02 mg/kg to 0.20 mg/kg, with 24 analytes validated in tomatoes, 33 in tamarillos and 28 in goldenberries. An initial risk assessment was enabled by monitoring 24 samples in the municipalities of El Peñol, Marinilla and San Vicente Ferrer. Risks were found for tomatoes, but no significant risks were found for tamarillos or goldenberries. PMID:24731326

  1. Select small core structure carbamates exhibit high contact toxicity to "carbamate-resistant" strain malaria mosquitoes, Anopheles gambiae (Akron.

    Directory of Open Access Journals (Sweden)

    Dawn M Wong

    Full Text Available Acetylcholinesterase (AChE is a proven target for control of the malaria mosquito (Anopheles gambiae. Unfortunately, a single amino acid mutation (G119S in An. gambiae AChE-1 (AgAChE confers resistance to the AChE inhibitors currently approved by the World Health Organization for indoor residual spraying. In this report, we describe several carbamate inhibitors that potently inhibit G119S AgAChE and that are contact-toxic to carbamate-resistant An. gambiae. PCR-RFLP analysis was used to confirm that carbamate-susceptible G3 and carbamate-resistant Akron strains of An. gambiae carry wild-type (WT and G119S AChE, respectively. G119S AgAChE was expressed and purified for the first time, and was shown to have only 3% of the turnover number (k(cat of the WT enzyme. Twelve carbamates were then assayed for inhibition of these enzymes. High resistance ratios (>2,500-fold were observed for carbamates bearing a benzene ring core, consistent with the carbamate-resistant phenotype of the G119S enzyme. Interestingly, resistance ratios for two oxime methylcarbamates, and for five pyrazol-4-yl methylcarbamates were found to be much lower (4- to 65-fold. The toxicities of these carbamates to live G3 and Akron strain An. gambiae were determined. As expected from the enzyme resistance ratios, carbamates bearing a benzene ring core showed low toxicity to Akron strain An. gambiae (LC(50>5,000 μg/mL. However, one oxime methylcarbamate (aldicarb and five pyrazol-4-yl methylcarbamates (4a-e showed good to excellent toxicity to the Akron strain (LC(50 = 32-650 μg/mL. These results suggest that appropriately functionalized "small-core" carbamates could function as a resistance-breaking anticholinesterase insecticides against the malaria mosquito.

  2. Health Risk Assessment of Pesticide Residues via Dietary Intake of Market Vegetables from Dhaka, Bangladesh

    OpenAIRE

    Md. Shakhaoat Hossain; Md. Alamgir Hossain; Md. Abdur Rahman; Md Mainul Islam; Md Atiqur Rahman; Tanveer Mehedi Adyel

    2013-01-01

    The present study was designed to assess the health risk of pesticide residues via dietary intake of vegetables collected from four top agro-based markets of Dhaka, Bangladesh. High performance liquid chromatography with a photo diode array detector (HPLC-PDA) was used to determine six organophosphorus (chlorpyrifos, fenitrothion, parathion, ethion, acephate, fenthion), two carbamate (carbaryl and carbofuran) and one pyrethroid (cypermethrin) pesticide residues in twelve samples of three comm...

  3. Comparative in vitro-in vivo percutaneous absorption of the pesticide propoxur

    NARCIS (Netherlands)

    Sandt, J.J.M. van de; Meuling, W.J.A.; Elliott, G.R.; Cnubben, N.H.P.; Hakkert, B.C.

    2000-01-01

    In vitro and in vivo skin absorption of the pesticide propoxur (2-isopropoxyphenyl N-methyl carbamate, commercially Baygon(TM) and Unden(TM); log Po/w 1.56, MW 209.2) was investigated. In vivo studies were performed in rats and human volunteers, applying the test compound to the dorsal skin and the

  4. Pesticides residues in water treatment plant sludge: validation of analytical methodology using liquid chromatography coupled to Tandem mass spectrometry (LC-MS/MS)

    International Nuclear Information System (INIS)

    The evolving scenario of Brazilian agriculture brings benefits to the population and demands technological advances to this field. Constantly, new pesticides are introduced encouraging scientific studies with the aim of determine and evaluate impacts on the population and on environment. In this work, the evaluated sample was the sludge resulted from water treatment plant located in the Vale do Ribeira, Sao Paulo, Brazil. The technique used was the reversed phase liquid chromatography coupled to electrospray ionization tandem mass spectrometry. Compounds were previously liquid extracted from the matrix. The development of the methodology demanded data processing in order to be transformed into reliable information. The processes involved concepts of validation of chemical analysis. The evaluated parameters were selectivity, linearity, range, sensitivity, accuracy, precision, limit of detection, limit of quantification and robustness. The obtained qualitative and quantitative results were statistically treated and presented. The developed and validated methodology is simple. As results, even exploring the sensitivity of the analytical technique, the work compounds were not detected in the sludge of the WTP. One can explain that these compounds can be present in a very low concentration, can be degraded under the conditions of the water treatment process or are not completely retained by the WTP. (author)

  5. Radiotracer Approaches to Carbamate Insecticide Toxicology

    International Nuclear Information System (INIS)

    Methylcarbamates constitute one of the major groups of insecticides. Many unresolved problems in their toxicology may be readily approached with radiotracer studies. Dimethylcarbamates have been prepared with carbonyl-C14-labelling and methylcarbamates withmethyl-, carbonyl-and ring-labelling utilizing carbon-14. The pharmacological action of these.compounds presumably results from acetylcholinesterase inhibition and may involve carbamylation. Reaction of carbonyl- or methyl-labelled carbamates with purified cholinesterase or other esterases would allow a critical examination of this carbamylation reaction and the ease of spontaneous and induced reactivation or decarbamylation. The physiological significance of cholinesterase inhibition might be examined by administering acetate-C14 and analysis for radiolabelled acetylcholine accumulation in nervous tissue, or by utilizing acetyl-C14-choline as the substrate for in vitro determination of the degree of cholinesterase inhibition in tissues of poisoned animals with minimal dilution of the inhibitors and enzymes during analysis. Some progress has been made with radiolabelled materials in investigating the metabolism of carbamate insecticides. Sevin (1-naphthyl methylcarbamate) has been most extensively studied along with its potential hydrolysis products. The assumption that the metabolism of Sevin involves an initial hydrolysis and then further decomposition of the fragments was not supported by carbon-14 studies. The major detoxification mechanism in mammals, and probably also in insects, results from initial oxidative attack on the carbamate by the microsomes in the presence of reduced nicotinamide-adenine dinucleotide phosphate. Sevin is rapidly metabolized in mammals, but the fate of certain of the fragments has not been resolved. Some of the metabolites appear in the milk of lactating animals. One step in the metabolism appears to be formation of the N-methylol derivative. Preliminary studies on the metabolism

  6. 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

  7. Mechanism of action of organophosphorus and carbamate insecticides.

    OpenAIRE

    Fukuto, T R

    1990-01-01

    Organophosphorus and carbamate insecticides are toxic to insects and mammals by virtue of their ability to inactivate the enzyme acetylcholinesterase. This review addresses the mechanism of inhibition of acetylcholinesterase by organophosphorus and carbamate esters, focusing on structural requirements necessary for anticholinesterase activity. The inhibition of acetylcholinesterase by these compounds is discussed in terms of reactivity and steric effects. The role of metabolic activation or d...

  8. Physicochemical studies of the carbamate-CO2-solvent system

    International Nuclear Information System (INIS)

    The formation of carbamate from CO2 and the various amine solutions has been investigated for the purpose of elucidating the structure of the species generated in the reaction. The amine solutions used were 1 and 2 molar solutions of di-n-butylamine (DNBA) in triethylamine (TEA), pure DNBA and pure TEA. It has been found that the nonaqueous solvent participates in the formation of carbamate in 1 and 2M-DNBA/TEA solutions as a proton acceptor in DNBA-carbamate formation. However, due to the high concentration of the solutions and the basicities of the amines, a significant amount of DNBA which does not form the DNBA-carbamate anion is also found to be participating as a proton acceptor. Pure TEA absorbs only 1/60 of the absorption by pure DNBA. The extent of TEA participation in the CO2-absorption process other than as a proton acceptor in DNBA-carbamate is negligible. The formation of carbamic acid and zwitterion have been found unlikely. 7 tables, 15 figs

  9. Development and validation of a multiresidue method for the determination of neonicotinoid and macrocyclic lactone pesticide residues in milk, fruits, and vegetables by ultra-performance liquid chromatography/MS/MS.

    Science.gov (United States)

    Kamel, Alaa; Qian, Yaorong; Kolbe, Elizabeth; Stafford, Charles

    2010-01-01

    A multiresidue method was developed and validated for the determination of 13 neonicotinoid pesticides and metabolites, and nine macrocyclic lactone pesticides and veterinary drugs using SPE and ultra-performance liquid chromatography/MS/MS. The method was validated in milk, orange, spinach, apple, plum, watermelon, green bean, zucchini, broccoli, strawberry, grape, and tomato by analyzing replicates of residue-free control samples fortified with a mixture of 22 target analytes at three concentration levels. The recoveries of the analytes from the fortified matrixes were mostly within 70-120%, except for some of the neonicotinoid metabolites. The LOD values varied by analyte and matrix and ranged between 0.001-2 ng/g. The developed method was successful in combining two widely different classes of compounds into a single analysis. PMID:20480883

  10. 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.

  11. Organic Pesticide Ingredients

    Science.gov (United States)

    ... Control a pest Integrated Pest Management What are pesticides? Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides ... Other types of pesticides Disponible en español Organic Pesticide Ingredients Organic foods are not necessarily pesticide-free. ...

  12. Pesticides and Human Health

    Science.gov (United States)

    ... Control a pest Integrated Pest Management What are pesticides? Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides ... Rodenticides Other types of pesticides Disponible en español Pesticides and Human Health Pesticides have a specific purpose ...

  13. 40 CFR 721.7200 - Perfluoroalkyl aromatic carbamate modified alkyl methacrylate copolymer.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Perfluoroalkyl aromatic carbamate... Significant New Uses for Specific Chemical Substances § 721.7200 Perfluoroalkyl aromatic carbamate modified...) The chemical substance identified generically as perfluoroalkyl aromatic carbamate modified...

  14. Pesticide Use and Self-Reported Symptoms of Acute Pesticide Poisoning among Aquatic Farmers in Phnom Penh, Cambodia

    Directory of Open Access Journals (Sweden)

    Hanne Klith Jensen

    2011-01-01

    Full Text Available Organophosphates and carbamates (OPs/CMs are known for their acetylcholinesterase inhibiting character. A cross-sectional study of pesticide handling practices and self-perceived symptoms of acute pesticide poisoning was conducted using questionnaire-based interviews with 89 pesticide sprayers in Boeung Cheung Ek (BCE Lake, Phnom Penh, Cambodia. The study showed that 50% of the pesticides used belonged to WHO class I + II and personal protection among the farmers were inadequate. A majority of the farmers (88% had experienced symptoms of acute pesticide poisoning, and this was significantly associated with the number of hours spent spraying with OPs/CMs (OR = 1.14, CI 95%: 1.02–1.28. The higher educated farmers reduced their risk of poisoning by 55% for each extra personal protective measure they adapted (OR = 0.45, CI 95%: 0.22–0.91. These findings suggest that improving safe pesticide management practices among the farmers and enforcing the effective banning of the most toxic pesticides will considerably reduce the number of acute pesticide poisoning episodes.

  15. Pesticide Movement

    Science.gov (United States)

    Pesticides generally include herbicides, insecticides and fungicides that play an important role in maintaining worldwide food and fiber production by controlling weeds that compete for water and nutrients or by eliminating pests that reduce yields. In the future, the role of pesticides and fertili...

  16. Growth and characterization of organic single crystal benzyl carbamate

    Science.gov (United States)

    Bala Solanki, S. Siva; Perumal, Rajesh Narayana; Suthan, T.; Bhagavannarayana, G.

    2015-10-01

    Benzyl carbamate single crystal is grown by a solution and vertical Bridgman technique for the first time. The cell parameters and morphologies are assessed from single crystal X-ray diffraction analysis. High resolution X-ray diffraction analysis indicates the crystalline perfection of the grown benzyl carbamate crystal. Fourier Transforms Infrared spectroscopy study has been applied to arrive at the different functional groups. Thermo gravimetric analysis and differential scanning calorimetry are used to study its thermal behavior. The microhardness test is carried out and the load dependent hardness is measured.

  17. 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. PMID:27396650

  18. Synthesis and decreasing Aβ content evaluation of arctigenin-4-yl carbamate derivatives.

    Science.gov (United States)

    Xu, Xingyu; Li, Cong; Lei, Min; Zhu, Zhiyuan; Yan, Jianming; Shen, Xu; Hu, Lihong

    2016-07-01

    A series of arctigenin-4-yl carbamate derivatives were synthesized and evaluated for potency in reducing β-amyloid (Aβ) content in HEK293-APPswe cells. Most of the arctigenin-4-yl aralkyl or aryl carbamate derivatives showed improved potency in reducing Aβ content. Among the synthesized compounds, arctigenin-4-yl (3-chlorophenyl)carbamate (20) exhibited the strongest potency with 78.7% Aβ content reduction at 20μM. Furthermore, the effect of arctigenin-4-yl (4-chlorophenyl)carbamate (19) and arctigenin-4-yl (3-chlorophenyl)carbamate (20) on lowing Aβ content was better than arctigenin under the concentrations of 1, 10 and 20μM.

  19. (1)H NMR-based metabonomic profiling of rat serum and urine to characterize the subacute effects of carbamate insecticide propoxur.

    Science.gov (United States)

    Liang, Yu-Jie; Wang, Hui-Ping; Long, Ding-Xin; Wu, Yi-Jun

    2012-09-01

    Carbamate insecticide propoxur is widely used in agriculture and public health programs. To prevent adverse health effects arising from exposure to this insecticide, sensitive methods for detection of early stage organismal changes are necessary. We present here an integrative metabonomic approach to investigate toxic effects of pesticide in experimental animals. Results showed that propoxur even at low dose levels can induce oxidative stress, impair liver function, enhance ketogenesis and fatty acid β-oxidation, and increase glycolysis, which contribute to the hepatotoxocity. These findings highlight the applicability of (1)H NMR spectroscopy and multivariate statistics in elucidating the toxic effects of propoxur.

  20. Vapor Pressure, Vaporization Enthalpy, Standard Enthalpy of Formation and Standard Entropy of n-Butyl Carbamate

    Institute of Scientific and Technical Information of China (English)

    Zuoxiang Zeng⁎; Zhihong Yang; Weilan Xue⁎; Xiaonan Li

    2014-01-01

    The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equation and the second virial coefficient was determined by the Vetere model. Then the standard enthalpy of vaporization for n-butyl carbamate was estimated. The heat capacity was measured for the solid state (299.39–324.2 K) and liquid state (336.65–453.21 K) by means of adiabatic calorimeter. The standard en-thalpy of formationΔfHϴ[crystal (cr),298.15 K] and standard entropy Sϴ(crystal,298.15 K) of the sub-stance were calculated on the basis of the gas-phase standard enthalpy of formationΔfHϴ(g,298.15 K) and gas-phase standard entropy Sϴ(g,298.15 K), which were estimated by the Benson method. The results are acceptable, validated by a thermochemical cycle.

  1. A Novel Approach for Evaluating Carbamate Mixtures for Dose Additivity

    Science.gov (United States)

    Two mathematical approaches were used to test the hypothesis ofdose-addition for a binary and a seven-chemical mixture ofN-methyl carbamates, toxicologically similar chemicals that inhibit cholinesterase (ChE). In the more novel approach, mixture data were not included in the ana...

  2. Study on the interaction of catalase with pesticides by flow injection chemiluminescence and molecular docking.

    Science.gov (United States)

    Tan, Xijuan; Wang, Zhuming; Chen, Donghua; Luo, Kai; Xiong, Xunyu; Song, Zhenghua

    2014-08-01

    The interaction mechanisms of catalase (CAT) with pesticides (including organophosphates: disulfoton, isofenphos-methyl, malathion, isocarbophos, dimethoate, dipterex, methamidophos and acephate; carbamates: carbaryl and methomyl; pyrethroids: fenvalerate and deltamethrin) were first investigated by flow injection (FI) chemiluminescence (CL) analysis and molecular docking. By homemade FI-CL model of lg[(I0-I)/I]=lgK+nlg[D], it was found that the binding processes of pesticides to CAT were spontaneous with the apparent binding constants K of 10(3)-10(5) L mol(-1) and the numbers of binding sites about 1.0. The binding abilities of pesticides to CAT followed the order: fenvalerate>deltamethrin>disulfoton>isofenphos-methyl>carbaryl>malathion>isocarbophos>dimethoate>dipterex>acephate>methomyl>methamidophos, which was generally similar to the order of determination sensitivity of pesticides. The thermodynamic parameters revealed that CAT bound with hydrophobic pesticides by hydrophobic interaction force, and with hydrophilic pesticides by hydrogen bond and van der Waals force. The pesticides to CAT molecular docking study showed that pesticides could enter into the cavity locating among the four subdomains of CAT, giving the specific amino acid residues and hydrogen bonds involved in CAT-pesticides interaction. It was also found that the lgK values of pesticides to CAT increased regularly with increasing lgP, Mr, MR and MV, suggesting that the hydrophobicity and steric property of pesticide played essential roles in its binding to CAT.

  3. Rapid determination of residues of pesticides in honey by µGC-ECD and GC-MS/MS: Method validation and estimation of measurement uncertainty according to document No. SANCO/12571/2013.

    Science.gov (United States)

    Paoloni, Angela; Alunni, Sabrina; Pelliccia, Alessandro; Pecorelli, Ivan

    2016-01-01

    A simple and straightforward method for simultaneous determination of residues of 13 pesticides in honey samples (acrinathrin, bifenthrin, bromopropylate, cyhalothrin-lambda, cypermethrin, chlorfenvinphos, chlorpyrifos, coumaphos, deltamethrin, fluvalinate-tau, malathion, permethrin and tetradifon) from different pesticide classes has been developed and validated. The analytical method provides dissolution of honey in water and an extraction of pesticide residues by n-Hexane followed by clean-up on a Florisil SPE column. The extract was evaporated and taken up by a solution of an injection internal standard (I-IS), ethion, and finally analyzed by capillary gas chromatography with electron capture detection (GC-µECD). Identification for qualitative purpose was conducted by gas chromatography with triple quadrupole mass spectrometer (GC-MS/MS). A matrix-matched calibration curve was performed for quantitative purposes by plotting the area ratio (analyte/I-IS) against concentration using a GC-µECD instrument. According to document No. SANCO/12571/2013, the method was validated by testing the following parameters: linearity, matrix effect, specificity, precision, trueness (bias) and measurement uncertainty. The analytical process was validated analyzing blank honey samples spiked at levels equal to and greater than 0.010 mg/kg (limit of quantification). All parameters were satisfactorily compared with the values established by document No. SANCO/12571/2013. The analytical performance was verified by participating in eight multi-residue proficiency tests organized by BIPEA, obtaining satisfactory z-scores in all 70 determinations. Measurement uncertainty was estimated according to the top-down approaches described in Appendix C of the SANCO document using the within-laboratory reproducibility relative standard deviation combined with laboratory bias using the proficiency test data.

  4. Monitoring of pesticide residues in vegetarian diet.

    Science.gov (United States)

    Kumari, Beena; Kathpal, T S

    2009-04-01

    Samples (28) of complete vegetarian diet consumed from morning till night i.e. tea, milk, breakfast, lunch, snacks, dinner, sweet dish etc. were collected from homes, hostels and hotels periodically from Hisar and analysed for detecting the residues of organochlorine, synthetic pyrethriod, organophosphate and carbamate insecticides. The estimation was carried out by using multi-residue analytical technique employing gas chromatograph (GC)-electron capture detector and GC-nitrogen phosphorous detector systems equipped with capillary columns. The whole diet sample was macerated in a mixer grinder and a representative sample in duplicate was analyzed for residues keeping the average daily diet of an adult to be 1,300 g. On comparing the data, it was found that actual daily intake (microgram/person/day) of lindane in two and endosulfan in four samples exceeded the acceptable daily intake. Residues of other pesticides in all the diet samples were lower than the acceptable daily intake (ADI) of the respective pesticides. The study concluded that although all the diet samples were found contaminated with one or the other pesticide, the actual daily intake of only a few pesticides was higher than their respective ADI. More extensive study covering other localities of Haryana has been suggested to know the overall scenario of contamination of vegetarian diet. PMID:18386151

  5. Pesticide contamination of the coastline of Martinique.

    Science.gov (United States)

    Bocquené, Gilles; Franco, Alain

    2005-01-01

    In January and February 2002, the presence of certain agricultural pesticides throughout the coastline of the Caribbean island of Martinique was investigated. The tropical climate of the French West Indies is suitable for banana production, which requires intensive use of pesticides. An inventory of all pesticides used on the island (compounds and tonnage) was compiled. Surveys and analyses revealed the presence of pesticides in the plumes of seven rivers. The organochlorine chlordecone and metabolites of aldicarb were detected at nearly all of the monitored sites, even though the use of chlordecone has been prohibited since 1993. Two triazines (ametryn and simazine) were also identified. The concentrations of carbamates and triazines detected in the water and sediment samples from Martinique are comparable to those reported for mainland France. Chlordecone concentrations in the sediment and particulate matter samples were, however, particularly high in the samples from Martinique. Toxicological implications are discussed. Of particular concern are the high levels of chlordecone (which is bioaccumulating and carcinogenic) and further monitoring of this compound is recommended, especially in fish and other sea-food products.

  6. Potential developmental neurotoxicity of pesticides used in Europe

    Directory of Open Access Journals (Sweden)

    Grandjean Philippe

    2008-10-01

    Full Text Available Abstract Pesticides used in agriculture are designed to protect crops against unwanted species, such as weeds, insects, and fungus. Many compounds target the nervous system of insect pests. Because of the similarity in brain biochemistry, such pesticides may also be neurotoxic to humans. Concerns have been raised that the developing brain may be particularly vulnerable to adverse effects of neurotoxic pesticides. Current requirements for safety testing do not include developmental neurotoxicity. We therefore undertook a systematic evaluation of published evidence on neurotoxicity of pesticides in current use, with specific emphasis on risks during early development. Epidemiologic studies show associations with neurodevelopmental deficits, but mainly deal with mixed exposures to pesticides. Laboratory experimental studies using model compounds suggest that many pesticides currently used in Europe – including organophosphates, carbamates, pyrethroids, ethylenebisdithiocarbamates, and chlorophenoxy herbicides – can cause neurodevelopmental toxicity. Adverse effects on brain development can be severe and irreversible. Prevention should therefore be a public health priority. The occurrence of residues in food and other types of human exposures should be prevented with regard to the pesticide groups that are known to be neurotoxic. For other substances, given their widespread use and the unique vulnerability of the developing brain, the general lack of data on developmental neurotoxicity calls for investment in targeted research. While awaiting more definite evidence, existing uncertainties should be considered in light of the need for precautionary action to protect brain development.

  7. Pesticides and oil and grease in selected streams and lakes in northeastern Louisiana, 2001

    Science.gov (United States)

    McGee, Benton D.

    2003-01-01

    A 6-month study was begun in April 2001 to determine the concentrations of pesticides or oil and grease in selected stream reaches and lakes within the Ouachita, Tensas, and Black River Basins in northeastern Louisiana. During April through September 2001, six monthly water samples for analysis of pesticides were collected from 22 sites: 17 sites were on 11 streams, and 5 sites were on 5 lakes. During Apirl through July 2001, four monthly samples for analysis of oil and grease were collected from 5 sites: 4 sites were on three streams, and 1 site was on a lake. A total of 131 water samples were analyzed for 17 pesticides (15 insecticides and 2 herbicides). The following classes of pesticides, as classified from the Pesticide Analysis (U.S. Environmental Protection Agency Region 6 Laboratory), are reported: organochlorine, nitrogen-phosphorus, and carbamate. The 8 pesticides detected in samples, in decreasing frequency, were as follow: atrazine, molinate, methyl parathion, 4,4'-DDT, carbofuran, diazinon, toxaphene, and 4,4'DDE. Organochlorine pesticides (insecticides) represented the majority (12 out of 17) of the pesticides analyzed. Of those 12 organochlorine pesticides, only 3 (4,4'-DDT, 4,4'-DDE, and toxaphene) were detected in the 131 samples. Of the organochlorine pesticides, 4,4'-DDT was detected most frequently (in 11 percent of the samples), and concentrations ranged from 1.22 to 4.70 ng/L (nanograms per liter). Nitrogen-phosphorus pesticides were the most frequently detected and abundant pesticides. Of all the pesticides analyzed, atrazine and molinate (nitrogen-phosphorus herbicides) were the pesticides most frequently detected (in 93 and 21 percent of the samples), had the highest and most wide-ranging concentrations (10.8 to 15,100 ng/L and 10.0 to 11,600 ng/L), and were most widely distributed throughout the study area. Carbofuran, a carbamate insecticide, was detected at 8 of the 22 pesticide data-collection sites and in 9.2 percent of the 131 samples

  8. 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.

  9. Correlation between Cholinesterase and Paraoxonase 1 Activities: Case Series of Pesticide Poisoning Subjects

    Directory of Open Access Journals (Sweden)

    S Austin Richard

    2013-08-01

    Full Text Available Introduction: Acute exposure to pesticide due to suicidal poisoning is the most extensive cause of pesticide exposure, compared with all other causes including agricultural or industrial exposure. Organophosphate (OP and carbamate group of pesticides can inhibit acetylcholinesterase; on the other hand, paraoxonase1 can detoxify organophosphate poisoning by hydrolyzing organophosphate metabolites. Methods: We have compared the serum paraoxonase1 status and cholinesterase activity of subjects who attempted to commit suicide by consuming OP pesticide. Cholinesterase and paraoxonase1 activity were measured spectrophotometrically using butyrylthiocholine and phenyl acetate as substrates, respectively. Results: A positive correlation was found between serum paraoxonase1 activity and cholinesterase activity among pesticide consumed subjects. Conclusion: Our results suggest that subjects with higher paraoxonase1 activity may have a better chance of detoxifying the lethal effect of acute organophosphate poisoning.

  10. Validation of method for determination of different classes of pesticides in aqueous samples by dispersive liquid-liquid microextraction with liquid chromatography-tandem mass spectrometric detection.

    Science.gov (United States)

    Caldas, Sergiane Souza; Costa, Fabiane Pinho; Primel, Ednei Gilberto

    2010-04-14

    In this study, a simple, rapid and efficient method has been developed for the extraction and preconcentration of different classes of pesticides, carbofuran (insecticide), clomazone (herbicide) and tebuconazole (fungicide) in aqueous samples by dispersive liquid-liquid microextraction (DLLME) coupled with liquid chromatography-tandem mass spectrometric detection. Some experimental parameters that influence the extraction efficiency, such as the type and volume of the disperser solvents and extraction solvents, extraction time, speed of centrifugation, pH and addition of salt were examined and optimized. Under the optimum conditions, the recoveries of pesticides in water at spiking levels between 0.02 and 2.0 microg L(-1) ranged from 62.7% to 120.0%. The relative standard deviations varied between 1.9% and 9.1% (n=3). The limits of quantification of the method considering a 50-fold preconcentration step were 0.02 microg L(-1). The linearity of the method ranged from 1.0 to 1000 microg L(-1) for all compounds, with correlation coefficients varying from 0.9982 to 0.9992. Results show that the method we propose can meet the requirements for the determination of pesticides in water samples. The comparison of this method with solid-phase extraction indicates that DLLME is a simple, fast, and low-cost method for the determination of pesticides in natural waters.

  11. Validation of a qualitative screening method for pesticides in fruits and vegetables by gas chromatography quadrupole-time of flight mass spectrometry with atmospheric pressure chemical ionization

    NARCIS (Netherlands)

    Portoles, T.; Mol, J.G.J.; Sancho, J.V.; Lopez, F.J.; Hernandez, F.

    2014-01-01

    A wide-scope screening method was developed for the detection of pesticides in fruit and vegetables. The method was based on gas chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer with an atmospheric pressure chemical ionization source (GC-(APCI)QTOF MS). A non-target acq

  12. National Pesticide Information Center

    Science.gov (United States)

    ... any pest." Herbicides Disinfectants Fungicides Insecticides Natural and Biological Pesticides Repellents Rodenticides Other types of pesticides Local Contacts Find local pesticide & pest control information Pesticide Information and Resources: Frequently Asked Questions: ...

  13. What Is a Pesticide?

    Science.gov (United States)

    ... Twitter Google+ Pinterest Contact Us Basic Information about Pesticide Ingredients Pesticide products contain both "active" and "inert" ingredients: What is a Pesticide? A pesticide is any substance or mixture of ...

  14. Phyt'Eaux Cités: application and validation of a programme to reduce surface water contamination with urban pesticides.

    Science.gov (United States)

    Botta, Fabrizio; Fauchon, Nils; Blanchoud, Hélène; Chevreuil, Marc; Guery, Bénédicte

    2012-01-01

    This paper presents first results of Phyt'Eaux Cités, a program put in place by the local water supply agency, the SEDIF (Syndicat des Eaux d'Ile-de-France), in collaboration with 73 local authorities, private societies and institutional offices (365 km(2)). The challenges included: measurement of the previous surface water contamination, control of urban pesticide applications, prevention of pesticide hazard on users and finally a overall reduction of surface water contamination. An inquiry on urban total pesticide amount was coupled with a surface water bi-weekly monitoring to establish the impact of more than 200 molecules upon the Orge River. For 2007, at least 4400 kg and 92 type of pesticides (essentially herbicides) were quantified for all urban users in the Phyt'Eaux Cités perimeter. At the outlet of the Orge River (bi-weekly sampling in 2007), 11 molecules were always detected above 0.1 μg L(-1). They displayed the mainly urban origin of pesticide surface water contamination. Amitrole, AMPA (Aminomethyl Phosphonic Acid), demethyldiuron, diuron, glyphosate and atrazine were quantified with a 100% of frequency in 2007 and 2008 at the Orge River outlet. During the year, peaks of contamination were also registered for MCCP, 2,4 MCPA, 2,4 D, triclopyr, dichlorprop, diflufènican, active substances used in large amount in the urban area. However, some other urban molecules, such as isoxaben or flazasulfuron, were detected with low frequency. During late spring and summer, contamination patterns and load were dominated by glyphosate, amitrole and diuron, essentially applied by cities and urban users. Both isoproturon and chlortoluron were quantified during autumn and winter months according to upstream agricultural practices. In conclusion, 3 years after the beginning of this programme, the cities reduced the use of 68% of the total pesticide amount. An improvement on surface water quality was found from 2008 and during 2009 for all pesticides. In particular

  15. Phyt'Eaux Cités: application and validation of a programme to reduce surface water contamination with urban pesticides.

    Science.gov (United States)

    Botta, Fabrizio; Fauchon, Nils; Blanchoud, Hélène; Chevreuil, Marc; Guery, Bénédicte

    2012-01-01

    This paper presents first results of Phyt'Eaux Cités, a program put in place by the local water supply agency, the SEDIF (Syndicat des Eaux d'Ile-de-France), in collaboration with 73 local authorities, private societies and institutional offices (365 km(2)). The challenges included: measurement of the previous surface water contamination, control of urban pesticide applications, prevention of pesticide hazard on users and finally a overall reduction of surface water contamination. An inquiry on urban total pesticide amount was coupled with a surface water bi-weekly monitoring to establish the impact of more than 200 molecules upon the Orge River. For 2007, at least 4400 kg and 92 type of pesticides (essentially herbicides) were quantified for all urban users in the Phyt'Eaux Cités perimeter. At the outlet of the Orge River (bi-weekly sampling in 2007), 11 molecules were always detected above 0.1 μg L(-1). They displayed the mainly urban origin of pesticide surface water contamination. Amitrole, AMPA (Aminomethyl Phosphonic Acid), demethyldiuron, diuron, glyphosate and atrazine were quantified with a 100% of frequency in 2007 and 2008 at the Orge River outlet. During the year, peaks of contamination were also registered for MCCP, 2,4 MCPA, 2,4 D, triclopyr, dichlorprop, diflufènican, active substances used in large amount in the urban area. However, some other urban molecules, such as isoxaben or flazasulfuron, were detected with low frequency. During late spring and summer, contamination patterns and load were dominated by glyphosate, amitrole and diuron, essentially applied by cities and urban users. Both isoproturon and chlortoluron were quantified during autumn and winter months according to upstream agricultural practices. In conclusion, 3 years after the beginning of this programme, the cities reduced the use of 68% of the total pesticide amount. An improvement on surface water quality was found from 2008 and during 2009 for all pesticides. In particular

  16. Herbicide and pesticide occurrence in the soils of children's playgrounds in Sarajevo, Bosnia and Herzegovina.

    Science.gov (United States)

    Sapcanin, Aida; Cakal, Mirsada; Imamovic, Belma; Salihovic, Mirsada; Pehlic, Ekrem; Jacimovic, Zeljko; Jancan, Gordan

    2016-08-01

    Pesticide pollution in Sarajevo public playgrounds is an important health and environmental issue, and the lack of information about it is causing concerns amongst the general population as well as researchers. Since children are in direct contact with surface soils on children's playgrounds, such soils should be much more carefully examined. Furthermore, herbicides and pesticides get transmitted from soil surfaces brought from outside the urban areas, or they get dispersed following their direct applications in urban areas. Infants' and children's health can be directly affected by polluted soils because of the inherent toxicity and widespread use of the different pesticides in urban environments such as playgrounds. In addition to that, the presence of chromated copper arsenate (CCA) wood preservative pesticide found as soil pollutant in playing equipment was also documented. Soil samples from playgrounds were collected and analyzed for triazines, carbamates, dithiocarbamates, phenolic herbicides and organochlorine pesticides. Samples for the determination of heavy metals Cu, Cr and As were prepared by microwave-assisted acid digestion, and the findings were determined by using an inductively coupled plasma optical emission spectrometer. Triazines, carbamates, dithiocarbamates, chlorphenoxy compounds, phenolic herbicides, organochlorine pesticides and organotin compounds were detected in playground soils and their determined concentrations (mg/kg) were respectively found as follows: playground soils.

  17. Optimization and validation of a methodology for the qualitative determination of polar pesticides in a carbonated soft drink and some cookies for EFS-CG/DEM

    International Nuclear Information System (INIS)

    Chemical analysis of polar pesticides has been qualitatively interest in forensic scientific research by toxicological qualities to the attainment of crimes against human life, pets and plants; associating people and objects in the scene and the possible ways in which the events occurred. The Unidad de Toxicos y Varios of the Seccion de Quimica Analitica of the Departamento de Ciencias Forenses has analyzed polar pesticides and other families to concentration levels, is compared to the environmental analysis and quality control of food. The compounds are used in Costa Rica in recent years as acute chemical weapon to commit crimes against human and animal life. The toxic and lethal amounts of polar pesticides in mammals orally have been milligram level. The Seccion de Quimica Analitica has developed a qualitative methodology to analyze polar pesticides as minor components. The need for reliable analytical quality results has made it necessary to approach a review of the methodology of routine. The review has been solved by selecting two matrices characteristics in such cases: a solid food commercially known as maria biscuits and a carbonated cola. Analytes have been selected based on: greater toxicity, broad spectrum of analytes polarity, the octanol-water partition constant, the water solubility among others. The extraction of analytes in matrices has been selected by solid-phase extraction. The instrumental technique used is gas chromatography with mass selective detector. A method of acquisition optimized in its injection is used. The analysis of instrumental signals were obtained in scanning mode all ions formed, known as Scan and by monitoring mode of ions selected ions (MIS), analysis of the data is acquired in Scan mode because concentration levels of work. The methodology for the qualitative determination of pesticide meets the criteria established for the chemical identification of analytes carbofuran, phorate, terbufos, methyl parathion, chlorpyrifos and

  18. GC/MIP/AED method for pesticide residue determination in fruits and vegetables.

    Science.gov (United States)

    Ting, K C; Kho, P

    1991-01-01

    This research describes the results of a gas chromatography/microwave induced plasma/atomic emission detection (GC/MIP/AED) method performed on a Hewlett-Packard 5921A system for pesticide residue analysis in fruits and vegetables. A total of 6 experiments were conducted: (1) sensitivity and linearity studies for elements S, P, Cl, and N by analyzing dursban; (2) a study of instrument response to Cl concentration in pesticide molecules; (3) organochlorinated pesticide recoveries; (4) organophosphate pesticide recoveries; (5) carbamate pesticide recoveries; and (6) investigation of metallic pesticides with plictran and vendex as standards. The rank according to sensitivity and linearity was found to be as follows: S-181 greater than P-178 greater than Cl-479 greater than N-174. Instrument response to the concentration of chlorine atoms in the pesticide molecule was linear, with a correlation coefficient of 0.89. Recoveries of organochlorinated pesticides were 91.7-109.3%, with the exception of citrus, whose recovery was affected by coeluting interferences. Organophosphate recoveries were 73.2% or higher, except for the cygon oxygen analog, which degraded in the GC system under all circumstances. Carbamate recoveries were inconsistent quantitatively; however, the information generated from elements N and S were useful for qualitative confirmation of other methods, such as LC postcolumn derivatization analysis. Overall, the GC/MIP/AED method is powerful for qualitative confirmation in pesticide residue analysis. The instrument's capability of acquiring multi-elements (Cl and P) selectively and accurately is an alternative method for organochlorinated and organophosphate pesticide residue analyses. In addition, the GC/MIP/AED system is easy to use, simple to maintain, and its chromatograms can be interpreted by any chromatography analyst without much prior training. PMID:1757425

  19. Examining pyrethroids, carbamates and neonicotenoids in fish, water and sediments from the Indus River for potential health risks.

    Science.gov (United States)

    Jabeen, Farhat; Chaudhry, Abdul Shakoor; Manzoor, Sadia; Shaheen, Tayybah

    2015-02-01

    This 3 × 3 factorial study assessed pyrethroids, carbamates and neonicotenoids groups of pesticides in replicated samples of three fish species from low (S1, reference), medium (S2) and heavy (S3) polluted sites receiving agricultural run-offs around the Indus River. Water and sediment samples from the same sites were also analysed for these pesticides by using high-performance liquid chromatography. Out of nine investigated pesticides, only three pesticides (deltamethrin, carbofuran and cypermethrin) were detected in fish and sediment samples. Deltamethrin in Cyprinus carpio ranged from 0.490 to 0.839 μg/g, mostly exceeding 0.5 μg/g as the maximum residual limit suggested by FAO-WHO, whereas it ranged from 0.214 to 0.318 μg/g in the sampled sediments. The carbofuran concentrations were 0.0425-0.066 and 0.613-0.946 μg/g in Labeo rohita and Channa marulius muscles respectively and 0.069-0.081 μg/g in the corresponding sediment samples. These values were either higher or lower than the maximum limit (0.1 μg/g) as suggested by FAO-WHO. Conversely, the cypermethrin concentration ranged from 0.141 to 0.174 in Ch. marulius and 0.183-0.197 μg/g in sediments which were both below the FAO-WHO maximum limit of 2 μg/g. No pesticide residues were detected in water from these sampling sites. Most selected physicochemical variables were within the acceptable range of World Health Organization for the water quality for aquatic life. The detected pesticide contents were mostly higher in fish muscles from heavily polluted sites. This is worrying because these pesticides may pose health risks for the fish and people of the study area. However, a preliminary risk assessment indicated that the calculated daily intake of detected pesticides by people consuming fish from the Indus River was low and did not present an immediate risk to the fish-consuming people. This study may be used as a benchmark to determine the safety of fish meat in order to develop intervention

  20. Synthesis of Novel Cellulose Carbamates Possessing Terminal Amino Groups and Their Bioactivity.

    Science.gov (United States)

    Ganske, Kristin; Wiegand, Cornelia; Hipler, Uta-Christina; Heinze, Thomas

    2016-03-01

    Cellulose phenyl carbonates are an excellent platform to synthesize a broad variety of soluble and functional cellulose carbamates. In this study, the synthesis of cellulose carbamates with terminal amino groups, namely ω-aminoethylcellulose- and ω-aminoethyl-p-aminobenzyl-cellulose carbamate, is discussed. The products are well soluble and their structures can be clearly described by NMR spectroscopy. The cellulose carbamates exhibit a bactericide and fungicide activity in vitro. The ω-aminoethylcellulose carbamate possesses a strong activity against Candida albicans and Staphylococcus aureus (IC50 of 0.02 mg mL(-1) and 0.05 mg mL(-1)). The antimicrobial activity and cytotoxicity can be improved by p-amino-benzylamine (ABA) as an additional substituent. The mixed cellulose carbamate exhibits a high biocompatibility (LC50 of 3.18 mg mL(-1)) and forms films on cotton and PES, which exhibit a strong activity against S. aureus and Klebsiella pneumoniae. PMID:26612063

  1. Obsolete pesticides

    Science.gov (United States)

    Showstack, Randy

    Several hundred tons of obsolete pesticide stocks worldwide will pose a threat to humans and the environment until the year 2030 in some regions, unless funding for waste disposal is significantly increased, the United Nations Food and Agriculture Organization (FAO) said in a message directed to donor governments and industry on May 24.“Deadly chemicals are contaminating the soils, groundwater, irrigation, and drinking water,” said Amemayehu Wodageneh, senior expert on obsolete pesticides for FAO. “These ‘forgotten’ stocks are a serious risk, [and] they could cause an environmental tragedy in rural areas and big cities. There is hardly any developing country that is not affected by the hazards of obsolete pesticides.”

  2. The Target of Benzimidazole Carbamate Against Cysticerci cellulosae

    Institute of Scientific and Technical Information of China (English)

    LI Qing-zhang; HAO Yan-hong; GAO Xue-jun; GAO Wen-xue; ZHAO Bing

    2007-01-01

    To study the target of benzimidazole carbamate drugs against Cysticerci cellulosae and give a theoretical basis for type evolution and new drug design, the changes of key enzyme activities and metabolite contents in the pathway of energy metabolism in C. cellulosae in vitro and in vivo were tested with albendazole and oxfendazole, respectively. Both albendazole and oxfendazole inhibited the pathways of anaerobic glycolysis, partial inversed tricarboxylic acid cycle of Taenia Solium oncosphere, immature and mature Cysticerci in vitro, and immature and mature Cysticerci in vivo to a certain degree, and enhanced fat decomposing, amino acid decomposing, xanthine decomposing metabolism, and on the other hand, the absorption of glucose was hindered; furthermore, both albendazole and oxfendazole inhibited the activities of the fumaric reductase (FR) complex noncompetently in vitro. Benzimidazole carbamate drugs could inhibit the activities of FR complex noncompetently and hinder the absorption of glucose.

  3. Generalisering og validering af model for afdrift af pesticider til læhegn og andre marknære biotoper

    DEFF Research Database (Denmark)

    Bruus, Marianne; Løfstrøm, Per; Andersen, Helle Vibeke;

    mængden af pesticider, der lander i læhegnene og dermed reducerer blomstring og frugtsætning. Samtidig viser såvel målinger som modelberegninger, at der ikke er den store effekt af sprøjtefrie bufferzoner på afdriften til læhegn, specielt ikke i den øverste del af læhegnene, hvor frugterne ofte er mest...

  4. Total Pesticide Exposure Calculation among Vegetable Farmers in Benguet, Philippines

    International Nuclear Information System (INIS)

    This was a cross-sectional study that investigated pesticide exposure and its risk factors targeting vegetable farmers selected through cluster sampling. The sampling size calculated with P=.05 was 211 vegetable farmers and 37 farms. The mean usage of pesticide was 21.35 liters. Risk factors included damaged backpack sprayer (34.7%), spills on hands (31.8%), and spraying against the wind (58%). The top 3 pesticides used were pyrethroid (46.4%), organophosphates (24.2%), and carbamates (21.3%). Those who were exposed to fungicides and insecticides also had higher total pesticide exposure. Furthermore, a farmer who was a pesticide applicator, mixer, loader, and who had not been given instructions through training was at risk of having higher pesticide exposure. The most prevalent symptoms were headache (64.1%), muscle pain (61.1%), cough (45.5%), weakness (42.4%), eye pain (39.9%), chest pain (37.4%), and eye redness (33.8%). The data can be used for the formulation of an integrated program on safety and health in the vegetable industry.

  5. Total Pesticide Exposure Calculation among Vegetable Farmers in Benguet, Philippines

    Directory of Open Access Journals (Sweden)

    Jinky Leilanie Lu

    2009-01-01

    Full Text Available This was a cross-sectional study that investigated pesticide exposure and its risk factors targeting vegetable farmers selected through cluster sampling. The sampling size calculated with =.05 was 211 vegetable farmers and 37 farms. The mean usage of pesticide was 21.35 liters. Risk factors included damaged backpack sprayer (34.7%, spills on hands (31.8%, and spraying against the wind (58%. The top 3 pesticides used were pyrethroid (46.4%, organophosphates (24.2%, and carbamates (21.3%. Those who were exposed to fungicides and insecticides also had higher total pesticide exposure. Furthermore, a farmer who was a pesticide applicator, mixer, loader, and who had not been given instructions through training was at risk of having higher pesticide exposure. The most prevalent symptoms were headache (64.1%, muscle pain (61.1%, cough (45.5%, weakness (42.4%, eye pain (39.9%, chest pain (37.4%, and eye redness (33.8%. The data can be used for the formulation of an integrated program on safety and health in the vegetable industry.

  6. Highly selective biomarkers for pesticides developed in Eisenia fetida using SELDI-TOF MS.

    Science.gov (United States)

    Park, Doo-San; Jeon, Hwang-Ju; Park, Eun-Sil; Bae, In Kyung; Kim, Yong-Eun; Lee, Sung-Eun

    2015-03-01

    The repeated use of pesticides, and their subsequent residues, has contributed to severe adverse effects on the environment, including risks to human health. Therefore, it is important to assess the quality of the environment to ensure it remains free from pesticide residues. The six pesticides tested in this study showed high mortality on Eisenia fetida with LC50 values ranging from 7.7 to 37.9 g L(-1). The strongest lethal effect resulted from the organochlorine insecticide endosulfan (LC50=7.7 g L(-1)). Following exposure to the carbamate pesticides, acetylcholinesterase activity in E. fetida decreased dramatically in comparison to the control. Carboxylesterase activity was only lowered in E. fetida exposed to propoxur, when compared to the control. The remaining five pesticides had no significant effect on carboxylesterase activity in E. fetida. In order to discover pesticide-specific biomarkers with differentially expressed proteins after exposure to pesticides, protein patterns of pesticide-treated E. fetida were analyzed using SELDI-TOF MS with Q10 ProteinChips. Protein patterns were compared with their intensities at the same mass-to-charge ratios (m/z). All 42 peaks had intensities with associated p-values less than 0.089, and 40 of these peaks had associated p-values of 0.05. Using SELDI-TOF MS technology, selective biomarkers for the six pesticides tested were found in E. fetida; four proteins with 5425, 5697, 9523, and 9868 m/z were consistently observed in the earthworms following exposure to the carbamates.

  7. New screening approach for risk assessment of pesticides in ambient air

    Science.gov (United States)

    Yusà, Vicent; Coscollà, Clara; Millet, Maurice

    2014-10-01

    We present a novel screening approach for inhalation risk assessment of currently used pesticides (CUPs) in ambient air, based on the measurements of pesticide levels in the inhalable fraction of the particulate matter (PM10). Total concentrations in ambient air (gas + particle phases) were estimated using a theoretical model of distribution of semi-volatile organic compounds between the gas and the particulate phase based on the octanol-air partition (Koa) of each pesticide. The proposed approach was used in a pilot study conducted in a rural station in Valencia (Spain) from April through to October 2010. Twenty out of 82 analysed pesticides were detected in average concentrations ranging from 1.63 to 117.01 pg m-3. For adults, children and infants the estimated chronic inhalation risk, expressed as Hazard Quotient (HQ) was pesticides. Likewise, the cumulative exposure for detected organophosphorus, pyrethroids and carbamates pesticides, was estimated using as metrics the Hazard Index (HI), which was less than 1 for the three families of pesticides assessed. The cancer risk estimated for the detected pesticides classified as Likely or Possible carcinogens was less than 1.15E-7 for infants. In our opinion, the screening approach proposed could be used in the monitoring and risk assessment of pesticides in ambient air.

  8. Validation and use of a QuEChERS-based gas chromatographic-tandem mass spectrometric method for multiresidue pesticide analysis in blackcurrants including studies of matrix effects and estimation of measurement uncertainty.

    Science.gov (United States)

    Walorczyk, Stanisław

    2014-03-01

    A triple quadrupole GC-QqQ-MS/MS method was optimized for multiresidue analysis of over 180 pesticides in blackcurrants. The samples were prepared by using a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) analytical protocol. To reduce matrix co-extractives in the final extract, the supernatant was cleaned up by dispersive-solid phase extraction (dispersive-SPE) with a mixture of sorbents: primary secondary amine (PSA), octadecyl (C18) and graphitized carbon black (GCB). The validation results demonstrated fitness for purpose of the streamlined method. The overall recoveries at the three spiking levels of 0.01, 0.05 and 0.2 mg kg(-1) spanned between 70% and 116% (102% on average) with relative standard deviation (RSD) values between 3% and 19% except for chlorothalonil (23%). Response linearity was studied in the range between 0.005 and 0.5 mg kg(-1). The matrix effect for each individual compound was evaluated through the study of ratios of the slopes obtained in solvent and blackcurrant matrix. The optimized method provided small matrix effect (30%, respectively. Following the application of "top-down" approach, the expanded measurement uncertainty was estimated as being 21% on average (coverage factor k=2, confidence level 95%). If compared with samples of other crops, the analyses of blackcurrants revealed a high percentage of exceedance of the legislative maximum residue levels (MRLs), as well as some instances of the detection of pesticides unapproved on this crop.

  9. [Survey of pesticide residues in imported spices and herbs (1997.4-2011.3)].

    Science.gov (United States)

    Kobayashi, Maki; Ohtsuka, Kenji; Tamura, Yasuhiro; Tomizawa, Sanae; Kinoshita, Teruaki; Kamijo, Kyoko; Iwakoshi, Keiko; Sato, Chizuko; Nagayama, Toshihiro; Takano, Ichiro

    2013-01-01

    A survey of pesticide residues in 313 samples of imported spices and herbs on the Tokyo market from April 1997 to March 2011 was carried out. Thirty-seven kinds of pesticides, including organophosphorus, organochlorine, pyrethroid, carbamate and others, were detected between levels of trace (below 0.01 ppm) and 3.3 ppm from 64 samples. The rate of detection was highest in peel (100%) followed by stem (66.7%), fruit (34.5%), bark (33.3%), flower (31.3%) and leaf (14.7%). No residues were detected in root, seed or whole grass. Organochlorine pesticides were detected in all plant parts. The insecticides were detected in products from all production areas, suggesting that their use is common. Residue levels of these pesticides were calculated as less than 1% of their ADI values, based on the daily intake of spices and herbs. Therefore, these spices and herbs should be safe when consumed in customary amounts.

  10. Detection and quantification of dithiocarbamate pesticides by Surface Enhanced Raman Spectroscopy (SERS)

    Science.gov (United States)

    Saute, Benjamin Calvin

    Dithiocarbamates are a subclass of carbamate pesticides that are widely used as insecticidal agents on food crops in the US and abroad. Quantitative determination of trace quantities of dithiocarbamates is necessary in order to mitigate potential human exposure via pesticide residues left on inadequately washed food items as well as groundwater contamination from agricultural runoff. The focus of this research is on the development and optimization of a Surface Enhanced Raman Spectroscopy (SERS) based analytical technique for the quantitative determination of trace amounts of dithiocarbamate pesticides in different matrices. Gold nanoparticles of different shapes and sizes will be investigated to determine the suitability of these materials as SERS active substrates for the trace analysis of dithiocarbamate pesticides. Analytical sensitivity will be evaluated by determining the limits of detection using established statistical methods.

  11. Herbicide and pesticide occurrence in the soils of children's playgrounds in Sarajevo, Bosnia and Herzegovina.

    Science.gov (United States)

    Sapcanin, Aida; Cakal, Mirsada; Imamovic, Belma; Salihovic, Mirsada; Pehlic, Ekrem; Jacimovic, Zeljko; Jancan, Gordan

    2016-08-01

    Pesticide pollution in Sarajevo public playgrounds is an important health and environmental issue, and the lack of information about it is causing concerns amongst the general population as well as researchers. Since children are in direct contact with surface soils on children's playgrounds, such soils should be much more carefully examined. Furthermore, herbicides and pesticides get transmitted from soil surfaces brought from outside the urban areas, or they get dispersed following their direct applications in urban areas. Infants' and children's health can be directly affected by polluted soils because of the inherent toxicity and widespread use of the different pesticides in urban environments such as playgrounds. In addition to that, the presence of chromated copper arsenate (CCA) wood preservative pesticide found as soil pollutant in playing equipment was also documented. Soil samples from playgrounds were collected and analyzed for triazines, carbamates, dithiocarbamates, phenolic herbicides and organochlorine pesticides. Samples for the determination of heavy metals Cu, Cr and As were prepared by microwave-assisted acid digestion, and the findings were determined by using an inductively coupled plasma optical emission spectrometer. Triazines, carbamates, dithiocarbamates, chlorphenoxy compounds, phenolic herbicides, organochlorine pesticides and organotin compounds were detected in playground soils and their determined concentrations (mg/kg) were respectively found as follows: <0.005, <0.05, <0.5, < 0.4, <0.1, <0.001 and <0.004. The determined contents (mg/kg) of Cu, Cr and As were in the ranges from 16.77 to 80.21, from 7.14 to 15.45 and from 3.31 to 4.43, respectively. Our preliminary results raise concerns about potential adverse effects of herbicides and pesticides on human health, which strengthens the case for a more preventative and protective approach to the uncontrolled presence of herbicides and pesticides in Sarajevo's playground soils. PMID

  12. Facile one-pot synthesis of unsymmetrical ureas, carbamates, and thiocarbamates from Cbz-protected amines.

    Science.gov (United States)

    Kim, Hee-Kwon; Lee, Anna

    2016-07-26

    A novel one-pot synthesis of unsymmetrical ureas, carbamates and thiocarbamates from Cbz-protected amines has been developed. In the presence of 2-chloropyridine and trifluoromethanesulfonyl anhydride, isocyanates are generated in situ, which facilitate rapid reaction with amines, alcohols, and thiols to afford the corresponding ureas, carbamates and thiocarbamates in high yields. PMID:27406041

  13. 40 CFR 180.212 - S-Ethyl cyclohexylethylthio-carbamate; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false S-Ethyl cyclohexylethylthio-carbamate; tolerances for residues. 180.212 Section 180.212 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Tolerances § 180.212 S-Ethyl cyclohexylethylthio-carbamate; tolerances for residues. (a) General....

  14. Subchronic Toxicity Study in Rats of Two New Ethyl-Carbamates with Ixodicidal Activity

    Directory of Open Access Journals (Sweden)

    María Guadalupe Prado-Ochoa

    2014-01-01

    Full Text Available Female and male Wistar rats were used to determine the subchronic oral toxicities of two new ethyl-carbamates with ixodicidal activities (ethyl-4-bromphenyl-carbamate and ethyl-4-chlorphenyl-carbamate. The evaluated carbamates were administered in the drinking water (12.5, 25 and 50 mg/kg/day for 90 days. Exposure to the evaluated carbamates did not cause mortality or clinical signs and did not affect food consumption or weight gain. However, exposure to these carbamates produced alterations in water consumption, hematocrit, percentages of reticulocytes, plasma proteins, some biochemical parameters (aspartate aminotransferase, gamma-glutamyl transpeptidase, cholinesterase, and creatinine activities, thiobarbituric acid reactive substances, and the relative weight of the spleen. Histologically, slight pathological alterations were found in the liver that were consistent with the observed biochemical alterations. The nonobserved adverse effect levels (NOAELs of the evaluated carbamates were 12.5 mg/kg/day for both the female and male rats. The low severity and reversibility of the majority of the observed alterations suggest that the evaluated carbamates have low subchronic toxicity.

  15. A meta-analysis synthesizing the effects of pesticides on swim speed and activity of aquatic vertebrates.

    Science.gov (United States)

    Shuman-Goodier, Molly E; Propper, Catherine R

    2016-09-15

    Pesticide contaminants are ubiquitous in aquatic environments and pose a threat to biodiversity. Pesticides also have diverse mechanisms of action that make it difficult to identify impacts on exposed wildlife. Behavioral measures represent an important link between physiological and ecological processes, and are often used to generalize sub-lethal effects of pesticide exposure. In order to bridge the toxicological and behavioral literature, and identify chemical classes that denote the largest threat, we conducted a meta-analysis summarizing the effects of pesticides on swim speed and activity of aquatic vertebrates. We found that exposure to environmentally relevant concentrations of pesticides reduced the swim speed of exposed amphibians and fish by 35%, and reduced overall activity by 72%. There were also differences in the magnitude of this effect across chemical classes, which likely reflect underlying physiological processes. Pyrethroids, carbamates, and organophosphates all produced a large decrease in swim speed, where as phosphonoglycines and triazines showed no overall effect. Pyrethroids, carbamates, organophosphates, organochlorines, and organotins also produced a large decrease in activity, while phosphonoglycines had no overall effect, and triazines had the opposite effect of increasing activity. Our results indicate that even sub-lethal concentrations of pesticides have a strong effect on critical behaviors of aquatic vertebrates, which can affect fitness and alter species interactions. We expect our synthesis can be used to identify chemical classes producing the largest sub-lethal effects for further research and management. PMID:27261557

  16. Pesticides residues in the Prochilodus costatus (Valenciennes, 1850) fish caught in the São Francisco River, Brazil.

    Science.gov (United States)

    Oliveira, Fabiano A; Reis, Lilian P G; Soto-Blanco, Benito; Melo, Marília M

    2015-01-01

    The objective of this study was to determine the levels of pesticides in the fish Prochilodus costatus caught in São Francisco River, one of most important rivers in Brazil. Thirty-six fish were captured in three different areas, and samples of the dorsal muscle and pooled viscera were collected for toxicological analysis. We evaluated the presence of 150 different classes of insecticides, fungicides, herbicides and acaricides by multiresidue analysis technique using liquid chromatography-tandem mass spectrometry (LC-MS/MS), with the limit of detection of 5 ppb. In this study, organophosphorus and carbamate pesticides were detected at the highest levels in the caught fish. Among the 41 organophosphorus pesticides surveyed, nine types were detected (chlorpyrifos, diazinon, dichlorvos, disulfoton, ethion, etrimfos, phosalone, phosmet and pyrazophos) in the muscle, viscera pool, or both in 22 (61.1%) fish. Sampled tissues of 20 (55.6%) fish exhibited at least one of the eight evaluated carbamate pesticides and their metabolites: aldicarb, aldicarb sulfoxide, carbaryl, carbofuran, carbosulfan, furathiocarb, methomyl and propoxur. Fungicides (carbendazim, benalaxyl, kresoxim-methyl, trifloxystrobin, pyraclostrobin and its metabolite BF 500 pyraclostrobin), herbicides (pyridate and fluasifop p-butyl), acaricide (propargite) and pyrethroid (flumethrin) were also detected. In conclusion, P. costatus fish caught in the São Francisco River contained residues of 17 different pesticides, in both muscles and the viscera pool, indicating heavy environmental contamination by pesticides in the study area.

  17. Applying Pesticides Safely

    OpenAIRE

    Latimer, Joyce G.

    2009-01-01

    Proper use of pesticides is essential for your safety and for that of the environment. Pesticides must be used correctly to be effective. This publication reviews the key factors in the proper use of pesticides.

  18. Synthesis and decreasing Aβ content evaluation of arctigenin-4-yl carbamate derivatives.

    Science.gov (United States)

    Xu, Xingyu; Li, Cong; Lei, Min; Zhu, Zhiyuan; Yan, Jianming; Shen, Xu; Hu, Lihong

    2016-07-01

    A series of arctigenin-4-yl carbamate derivatives were synthesized and evaluated for potency in reducing β-amyloid (Aβ) content in HEK293-APPswe cells. Most of the arctigenin-4-yl aralkyl or aryl carbamate derivatives showed improved potency in reducing Aβ content. Among the synthesized compounds, arctigenin-4-yl (3-chlorophenyl)carbamate (20) exhibited the strongest potency with 78.7% Aβ content reduction at 20μM. Furthermore, the effect of arctigenin-4-yl (4-chlorophenyl)carbamate (19) and arctigenin-4-yl (3-chlorophenyl)carbamate (20) on lowing Aβ content was better than arctigenin under the concentrations of 1, 10 and 20μM. PMID:27212069

  19. Pesticides in the Ebro River basin: Occurrence and risk assessment.

    Science.gov (United States)

    Ccanccapa, Alexander; Masiá, Ana; Navarro-Ortega, Alícia; Picó, Yolanda; Barceló, Damià

    2016-04-01

    In this study, 50 pesticides were analyzed in the Ebro River basin in 2010 and 2011 to assess their impact in water, sediment and biota. A special emphasis was placed on the potential effects of both, individual pesticides and their mixtures, in three trophic levels (algae, daphnia and fish) using Risk Quotients (RQs) and Toxic Units (TUs) for water and sediments. Chlorpyrifos, diazinon and carbendazim were the most frequent in water (95, 95 and 70% of the samples, respectively). Imazalil (409.73 ng/L) and diuron (150 ng/L) were at the highest concentrations. Sediment and biota were less contaminated. Chlorpyrifos, diazinon and diclofenthion were the most frequent in sediments (82, 45 and 21% of the samples, respectively). The only pesticide detected in biota was chlorpyrifos (up to 840.2 ng g(-1)). Ecotoxicological risk assessment through RQs showed that organophosphorus and azol presented high risk for algae; organophosphorus, benzimidazoles, carbamates, juvenile hormone mimic and other pesticides for daphnia, and organophosphorus, azol and juvenile hormone mimics for fish. The sum TUsite for water and sediments showed values pesticide residues present. PMID:26802514

  20. Pesticides in the Ebro River basin: Occurrence and risk assessment.

    Science.gov (United States)

    Ccanccapa, Alexander; Masiá, Ana; Navarro-Ortega, Alícia; Picó, Yolanda; Barceló, Damià

    2016-04-01

    In this study, 50 pesticides were analyzed in the Ebro River basin in 2010 and 2011 to assess their impact in water, sediment and biota. A special emphasis was placed on the potential effects of both, individual pesticides and their mixtures, in three trophic levels (algae, daphnia and fish) using Risk Quotients (RQs) and Toxic Units (TUs) for water and sediments. Chlorpyrifos, diazinon and carbendazim were the most frequent in water (95, 95 and 70% of the samples, respectively). Imazalil (409.73 ng/L) and diuron (150 ng/L) were at the highest concentrations. Sediment and biota were less contaminated. Chlorpyrifos, diazinon and diclofenthion were the most frequent in sediments (82, 45 and 21% of the samples, respectively). The only pesticide detected in biota was chlorpyrifos (up to 840.2 ng g(-1)). Ecotoxicological risk assessment through RQs showed that organophosphorus and azol presented high risk for algae; organophosphorus, benzimidazoles, carbamates, juvenile hormone mimic and other pesticides for daphnia, and organophosphorus, azol and juvenile hormone mimics for fish. The sum TUsite for water and sediments showed values pesticide residues present.

  1. Evaluation of carbamate insecticides as chemotherapeutic agents for cancer

    Directory of Open Access Journals (Sweden)

    Mohd. Amanullah

    2011-01-01

    Full Text Available Background: Cancer chemotherapy has already been in practice by the use of toxins and some of the specific poisonous compounds of cyanide derivatives. Carbamate insecticides inhibit cellular metabolism including energy, protein, and nucleic acid metabolism, thereby, causing cell regression and death. Aim: Preliminary evaluation of three carbamate insecticides, namely, baygon, carbaryl, and carbofuran as chemotherapeutic agents for cancer is undertaken in the present study. Materials and Methods: The toxicity of carbamates on squamous cell carcinoma was assessed in-vitro using dye binding tests. Cells were grown in microtitration ELISA plates, as adherent cultures, for six hours, and then exposed to the drugs for 2, 4, 8, and 12 hours, and finally stained with neutral red, to assess the viable cell number, and with methylene blue for the determination of protein in the monolayer. Optical density was read in an ELISA reader. Statistical Analysis: The data obtained during the experiment was subjected to statistical analysis by using the student ′t′ test. Results: The results indicated that the percentage of the viable cell number reduced with an increase in the time of exposure of the drugs. Exposure of the tumor cells to the drugs for 12 hours detached them completely from the wells, and hence, all the cells were washed out. Exposure of the drugs prior to the establishment of the culture in-vitro resulted in the non-formation of the monolayer in the wells. Conclusions: Among the three drugs studied, the survival percent was least with carbaryl treatment followed by baygon, and with carbofuran treatment it was almost near to control group.

  2. Inhibition Mechanism of Cholinesterases by Carbamate: A Theoretical Study

    Institute of Scientific and Technical Information of China (English)

    YAO Yuan; LI Ze-sheng

    2008-01-01

    The density functional theory at the B3LYP/6-311G(d,p) level was applied to exploring the inhibition mechanism of cholinesterases by carbamate.The results indicate that the inhibition reactions with or without the catalytic effect of the catalytic triad in cholinesterases underwent a two-step addition-elimination mechanism,which is in good agreement with the proposed mechanism.The solvent has a strong effect on the inhibition reactions and the reaction with the catalytic triad in the solvent phase is close to the real reaction under biological condition.

  3. Ultra-Trace Determination of Methyl Carbamate and Ethyl Carbamate in Local Wines by GC-FID Following Pre concentration with C18-SPE

    Directory of Open Access Journals (Sweden)

    Supawadee Sarawan

    2014-09-01

    Full Text Available An analytical method is described for ultra-trace determination of methyl carbamate and ethyl carbamate in locally produced fruit wines. The quantitative analysis involves with dichloromethane extraction followed by 30-fold preconcentration using C18 SPE prior to measurement by capillary GC-FID. Under the optimized conditions, a good linearity of their calibration curves was obtained in the range of 0.1-50.0 mg/L with r2 > 0.994. LOD and LOQ were 3.3-16.7 µg/L and 11.1-55.6 µg/L, respectively. The averaged recovery of these carbamates was ranged of 82.2-95.2% with RSD < 8.76%. The procedure was applied to determine both carbamate residues in various local wine samples. It was found that the concentration range of methyl carbamate (6.9-24.1 µg/L was rather fluctuated and higher than that of ethyl carbamate (2.6-4.3 µg/L, suggesting that is a certain residual background contamination naturally occurring in the wine fermentation.

  4. Comparative effect of pesticides on brain acetylcholinesterase in tropical fish.

    Science.gov (United States)

    Assis, Caio Rodrigo Dias; Linhares, Amanda Guedes; Oliveira, Vagne Melo; França, Renata Cristina Penha; Carvalho, Elba Veronica Matoso Maciel; Bezerra, Ranilson Souza; de Carvalho, Luiz Bezerra

    2012-12-15

    Monitoring of pesticides based on acetylcholinesterase (AChE; EC 3.1.1.7) inhibition in vitro avoids interference of detoxification defenses and bioactivation of some of those compounds in non-target tissues. Moreover, environmental temperature, age and stress are able to affect specific enzyme activities when performing in vivo studies. Few comparative studies have investigated the inter-specific differences in AChE activity in fish. Screening studies allow choosing the suitable species as source of AChE to detect pesticides in a given situation. Brain AChE from the tropical fish: pirarucu (Arapaima gigas), cobia (Rachycentron canadum) and Nile tilapia (Oreochromis niloticus) were characterized and their activities were assayed in the presence of pesticides (the organophosphates: dichlorvos, diazinon, chlorpyrifos, temephos, tetraethyl pyrophosphate- TEPP and the carbamates: carbaryl and carbofuran). Inhibition parameters (IC₅₀ and Ki) for each species were found and compared with commercial AChE from electric eel (Electrophorus electricus). Optimal pH and temperature were found to be 8.0 and 35-45 °C, respectively. A. gigas AChE retained 81% of the activity after incubation at 50 °C for 30 min. The electric eel enzyme was more sensitive to the compounds (mainly carbofuran, IC₅₀ of 5 nM), excepting the one from A. gigas (IC₅₀ of 9 nM) under TEPP inhibition. These results show comparable sensitivity between purified and non-purified enzymes suggesting them as biomarkers for organophosphorus and carbamate detection in routine environmental and food monitoring programs for pesticides.

  5. Multiresidue Analysis of 86 Pesticides Using Gas Chromatography Mass Spectrometry: II-Nonleafy Vegetables

    Directory of Open Access Journals (Sweden)

    M. H. EL-Saeid

    2013-01-01

    Full Text Available A total of 1057 samples of fresh vegetables from import and domestic production were analyzed (cold pepper, egg plant, carrot, cucumber, potato, hot pepper, cultivation tomato, squash, beans, okra, onions, cauliflower, and green house tomato. The aim of this study was to investigate pesticide residues in market foods in Riyadh, which have been collected from Riyadh Development Company (Al-Tamer Vegetables Market. Pesticide residues were determined by gas chromatography with mass selective detector (GC-MSD. A multiresidue method was developed and described for simultaneous determination of 86 pesticides commonly used in crop protection. This method used to determine 86 pesticide residues with a broad range of physicochemical properties in fresh vegetables related to organophosphorus (OPP, organochlorines (OCP, pyrethroids, and carbamates mainly used in agriculture. Sample extract was cleaned up by using AOAC method. Pesticide residues above the maximum residue limits (MRL were detected in 15.89% of the total samples (168 from 1057 samples, but 83.90% of the total samples (887 from 1057 samples has no residues or contained pesticide residues at or below MRL. The detected and most frequently found pesticide residues were permethrin (45 times and endosulfan (34 times followed by deltamethrin (27 times. The findings of this study pointed to the following recommendations: the need for a monitoring program for pesticide residues in imported food crops.

  6. Comparison Between the Efficiency of Advanced Oxidation Process and Coagulation for Removal Organophosphorus and Carbamat Pesticides

    Directory of Open Access Journals (Sweden)

    A.R Rahmani

    2011-10-01

    Full Text Available Background and Objectives: Water pollution by pesticides has adverse effects on the environment and human health, as well .In recent years, advanced oxidation processes, have been gone through to a very high degree for pesticides removal. Poly-Aluminum chloride (PAC used for water treatment, can be effective on pesticides removal. The aim of this research was to study the use of UV/O3 and PAC in the removal of pesticides from drinking water.Materials and Methods: In this descriptive- analytical survey, specific concentrations of pesticides (1,5,10,15,20 ppm;namely Diazinon, Chlorpyrifos, Carbaril were prepared through addition to deionized water. Dichloromethane was used for samples' extraction, samples extracted with Liquid- Liquid & Solid-phase extraction , finally entered bath reactor at pH (6,7,9 .The samples then exposed to UV/O3at contact time of (0.5,1,1.5 and 2 hours . In the PAC pilot , the effects of various concentrations of pesticides, and PAC - ranging (12/24 and 36 ppm were investigated for the efficacy of pesticides removal. All samples analyzed by GC/MS/MS and HPLC. Results: It was found that in UV/O3 reactor, with the rise of pH, decrease in pesticides concentration, and rise of contact time, the efficiency of removal increased too. In the PAC pilot, increase in PAC concentration and decrease in pesticides concentration , both increased the efficiency. Besides, both of the methods showed high efficiencies in the removal of both pesticides,i-e. halogenated Organophosphorus (Chlorpyrifos , non- halogenated Organophosphorus (Diazinon at the degree of over (%80 ; In case of carbamate pesticides (e.g. Carbaril efficiency was over (>%90. One-Way Anova & Two -Way Anova were used to analyze the obtained data.Conclusion: According these results these two methods are suggested for the removal of pesticides from aqueous solutions.

  7. The Preparation and Application of Methyl Carbamate through Alcoholysis of Urea%氨基甲酸甲酯的尿素醇解法制备及其应用研究进展

    Institute of Scientific and Technical Information of China (English)

    侯国宁

    2012-01-01

    As a kind of important fine chemicals, methyl carbamate was widely applied in many areas of chemical in- dustry, which was the research focus of urea downstream at present. The research progress of methyl carbamate through al- coholysis of urea such as normal temperature and pressure catalytic synthesis, medium temperature and medium pressure catalytic synthesis and high pressure synthesis without catalyst were generalized. At the same time, its applications on or- ganic synthesis, medicine, and pesticides were reviewed to have a thorough understanding on methyl carbamate industry.%氨基甲酸甲酯作为一种重要的精细化学品,在众多领域中有着广泛的应用,当前已成为尿素下游领域竞相开发的重点。概述了常温常压催化合成、中温中压催化合成及无催化剂高压合成尿素醇解法生产氨基甲酸甲酯工艺研究进展,同时展望其在有机合成、医药、农药等领域的应用,以期对氨基甲酸甲酯行业的发展有较为深入的了解。

  8. B-type esterases in the snail Xeropicta derbentina: An enzymological analysis to evaluate their use as biomarkers of pesticide exposure

    Energy Technology Data Exchange (ETDEWEB)

    Laguerre, Christel [Universite d' Avignon et des Pays de Vaucluse, UMR 406 UAPV/INRA, F-84914 Avignon (France); INRA, Laboratoire de Toxicologie Environnementale, UMR 406 UAPV/INRA, F-84914 Avignon (France); Sanchez-Hernandez, Juan C. [Laboratory of Ecotoxicology, Faculty of Environmental Science, University of Castilla-La Mancha, Avda. Carlos III s/n, 45071 Toledo (Spain); Koehler, Heinz R. [Animal Physiological Ecology, University of Tuebingen, Konrad-Adenauer-Strasse 20, D-72072 Tuebingen (Germany); Triebskorn, Rita [Animal Physiological Ecology, University of Tuebingen, Konrad-Adenauer-Strasse 20, D-72072 Tuebingen (Germany); Steinbeis-Transfer Center for Ecotoxicology and Ecophysiology, Blumenstrasse 13, D-72108 Rottenburg (Germany); Capowiez, Yvan [INRA, Unite PSH, F- 84914 Avignon (France); Rault, Magali [Universite d' Avignon et des Pays de Vaucluse, UMR 406 UAPV/INRA, F-84914 Avignon (France); INRA, Laboratoire de Toxicologie Environnementale, UMR 406 UAPV/INRA, F-84914 Avignon (France); Mazzia, Christophe [Universite d' Avignon et des Pays de Vaucluse, UMR 406 UAPV/INRA, F-84914 Avignon (France); INRA, Laboratoire de Toxicologie Environnementale, UMR 406 UAPV/INRA, F-84914 Avignon (France)], E-mail: mazzia@avignon.inra.fr

    2009-01-15

    The study was prompted to characterize the B-type esterase activities in the terrestrial snail Xeropicta derbentina and to evaluate its sensitivity to organophosphorus and carbamate pesticides. Specific cholinesterase and carboxylesterase activities were mainly obtained with acetylthiocholine (K{sub m} = 77.2 mM; V{sub max} = 38.2 mU/mg protein) and 1-naphthyl acetate (K{sub m} = 222 mM, V{sub max} = 1095 mU/mg protein) substrates, respectively. Acetylcholinesterase activity was concentration-dependently inhibited by chlorpyrifos-oxon, dichlorvos, carbaryl and carbofuran (IC50 = 1.35 x 10{sup -5}-3.80 x 10{sup -8} M). The organophosphate-inhibited acetylcholinesterase activity was reactivated in the presence of pyridine-2-aldoxime methochloride. Carboxylesterase activity was inhibited by organophosphorus insecticides (IC50 = 1.20 x 10{sup -5}-2.98 x 10{sup -8} M) but not by carbamates. B-esterase-specific differences in the inhibition by organophosphates and carbamates are discussed with respect to the buffering capacity of the carboxylesterase to reduce pesticide toxicity. These results suggest that B-type esterases in X. derbentina are suitable biomarkers of pesticide exposure and that this snail could be used as sentinel species in field monitoring of Mediterranean climate regions. - Characterization of the B-type esterases in the terrestrial snail Xeropicta derbentina in order to evaluate pesticide exposure.

  9. tert-Butyl N-benzyl-N-[4-(4-fluorobenzoylmethyl-2-pyridyl]carbamate

    Directory of Open Access Journals (Sweden)

    Pierre Koch

    2008-11-01

    Full Text Available In the crystal structure of the title compound, C25H25FN2O3, the pyridine ring makes dihedral angles of 75.1 (3, 39.4 (3 and 74.6 (3° with the phenyl ring, the carbamate plane and the 4-fluorophenyl ring, respectively. The phenyl ring makes dihedral angles of 77.2 (3 and 23.6 (3° with the carbamate plane and the 4-fluorophenyl ring, respectively. The 4-fluorophenyl ring is perpendicular to the carbamate plane, the dihedral angle between them being 89.5 (3°.

  10. Study of Inhibition, Reactivation and Aging Processes of Pesticides Using Graphene Nanosheets/Gold Nanoparticles-Based Acetylcholinesterase Biosensor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lin; Long, Linjuan; Zhang, Weiying; Du, Dan; Lin, Yuehe

    2012-09-10

    Organophosphate (OP) and carbamate pesticides exert their toxicity via attacking the hydroxyl moiety of serine in the 'active site' of acetylcholinesterase (AChE). In this paper we developed a stable AChE biosensor based on self-assembling AChE to graphene nanosheet (GN)-gold nanoparticles (AuNPs) nanocomposite electrode for investigation of inhibition, reactivation and aging processes of different pesticides. It is confirmed that pesticides can inhibit AChE in a short time. OPs poisoning is treatable with oximes while carbarmates exposure is insensitive to oximes. The proposed electrochemical approach thus provides a new simple tool for comparison of pesticide sensitivity and guide of therapeutic intervention.

  11. Evaluation of Four Bio fertilizers for Bioremediation of Pesticide contaminated Soil

    International Nuclear Information System (INIS)

    Experiments were conducted to asses the ability of mixed populations of microorganisms which produced as a bio fertilizers by the General Organization of Agriculture Fund, Ministry of Agriculture, Egypt (phosphoren, microbien, cerealin and azospirillum) to degrade five selected pesticides representing different classes including organophosphate, carbamate and chlorinated organic compounds. There were differences in rates of biotransformation, suggesting the selective induction of certain metabolic enzymes. Inoculation of soil incorporated with malathion, fenamiphos, carbaryl, aldicarb and dieldrin, resulted in ca. 80-90% removal of malathion and fenamiphos within 8 days, carbaryl and aldicarb within 11-15 days respectively. Dieldrin removal occurred slowly within 2 months. These data suggest that bioremediate may act as potential candidates for soil inoculation to bioremediate pesticide contaminated soil. The production of Co2 (soil respiration ) was stimulated by some pesticides. In samples with microbien, an about 2 times higher Co2 production was measured

  12. Postcolumn photolysis of pesticides for fluorometric determination by high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Miles, C.J.; Moye, H.A.

    1988-02-01

    A high-performance liquid chromatography postcolumn reaction detector that employs UV photolysis with an optional reaction by using o-phthalaldehyde-2-mercaptoethanol (OPA-MERC) followed by fluorescence detection was found to be useful for several classes of pesticides. In the presence of the OPA-MERC reagent, most carbamates, carbamoyl oximes, carbamothioic acids, and substituted ureas gave a sensitive response while the response of dithiocarbamates, phenylamides, and phenylcarbamates varied. The response of most of the pesticides tested was significantly affected by the solvent used. Method detection limits for aldicarb sulfoxide, aldicarb, propoxur, thiram, and neburon in ground water were 2.5, 2.3, 3.3, 3.8, and 2.0 ..mu..g/L, respectively. In the absence of OPA-MERC reagent, several of the substituted aromatic compounds also gave strong fluorescence after photolysis. This detector is applicable to a broad range of nitrogenous pesticides.

  13. Ethyl carbamate levels in selected fermented foods and beverages.

    Science.gov (United States)

    Canas, B J; Havery, D C; Robinson, L R; Sullivan, M P; Joe, F L; Diachenko, G W

    1989-01-01

    Ethyl carbamate (EC), also known as urethane, is an animal carcinogen and a by-product of fermentation. Because EC has been found in distilled spirits and wines, a variety of fermented foods and beverages were analyzed to assess its occurrence in other products. Previously described methods using a gas chromatograph-thermal energy analyzer with a nitrogen converter were modified for each matrix and gave recoveries of greater than 80%, with a limit of detection in the 1-2 micrograms/kg (ppb) range. A total of 152 test samples were analyzed; EC levels ranged from none found to 3 ppb in 15 cheeses, 6 teas, 12 yogurts, and 8 ciders; from none found to 13 ppb in 30 breads and 69 malt beverages; and from none found to 84 ppb in 12 soy sauces. Gas chromatography/mass spectrometry/mass spectrometry was used to confirm EC identity and to quantitate EC in selected food extracts. PMID:2592308

  14. Novel aryl carbamate derivatives of metronidazole as potential antiamoebic agents.

    Science.gov (United States)

    Hayat, Faisal; Wahedi, Hussain Mustatab; Park, Seonghyeok; Tariq, Saba; Azam, Amir; Shin, Dongyun

    2016-01-01

    A series of novel aryl carbamate derivatives of metronidazole (MNZ) were designed, synthesized, and screened for antiamoebic activity. As compared to MNZ, most of the derivatives exhibited moderate to excellent activity against the HM1:IMSS strain of Entamoeba histolytica. Compounds 7, 14, 16, 19, and 21 exhibited the most promising antiamoebic activity with IC50 values of 0.24, 0.08, 0.26, 0.26, and 0.15 μM, respectively, compared to that of MNZ (1.78 μM). Moreover, from the toxicological studies of these compounds on human melanocytes, the melan-a cell line revealed that the potent compounds are nontoxic at concentrations ranging from 2.5 to 50 μM. PMID:26597858

  15. Potent Urea and Carbamate Inhibitors of Soluble Epoxide Hydrolases

    Science.gov (United States)

    Morisseau, Christophe; Goodrow, Marvin H.; Dowdy, Deanna; Zheng, Jiang; Greene, Jessica F.; Sanborn, James R.; Hammock, Bruce D.

    1999-08-01

    The soluble epoxide hydrolase (sEH) plays a significant role in the biosynthesis of inflammation mediators as well as xenobiotic transformations. Herein, we report the discovery of substituted ureas and carbamates as potent inhibitors of sEH. Some of these selective, competitive tightbinding inhibitors with nanomolar Ki values interacted stoichiometrically with the homogenous recombinant murine and human sEHs. These inhibitors enhance cytotoxicity of trans-stilbene oxide, which is active as the epoxide, but reduce cytotoxicity of leukotoxin, which is activated by epoxide hydrolase to its toxic diol. They also reduce toxicity of leukotoxin in vivo in mice and prevent symptoms suggestive of acute respiratory distress syndrome. These potent inhibitors may be valuable tools for testing hypotheses of involvement of diol and epoxide lipids in chemical mediation in vitro or in vivo systems.

  16. The thermal desorption of CO2 from amine carbamate solutions for the 13C isotope enrichment

    Science.gov (United States)

    Dronca, S.; Varodi, C.; Gligan, M.; Stoia, V.; Baldea, A.; Hodor, I.

    2012-02-01

    The CO2 desorption from amine carbamate in non-aqueous solvents is of major importance for isotopic enrichment of 13C. A series of experiments were carried out in order to set up the conditions for the CO2 desorption. For this purpose, a laboratory- scale plant for 13C isotope separation by chemical exchange between CO2 and amine carbamate was designed and used. The decomposition of the carbamate solution was mostly produced in the desorber and completed in the boiler. Two different-length desorbers were used, at different temperatures and liquid flow rates of the amine-non-aqueous solvent solutions. The residual CO2 was determined by using volumetric and gaschromatographic methods. These results can be used for enrichment of 13C by chemical exchange between CO2 and amine carbamate in nonaqueous solvents.

  17. Pesticide transport simulation in a tropical catchment by SWAT

    International Nuclear Information System (INIS)

    The application of agrochemicals in Southeast Asia is increasing in rate, variety and toxicity with alarming speed. Understanding the behavior of these different contaminants within the environment require comprehensive monitoring programs as well as accurate simulations with hydrological models. We used the SWAT hydrological model to simulate the fate of three different pesticides, one of each usage type (herbicide, fungicide and insecticide) in a mountainous catchment in Northern Thailand. Three key parameters were identified: the sorption coefficient, the decay coefficient and the coefficient controlling pesticide percolation. We yielded satisfactory results simulating pesticide load dynamics during the calibration period (NSE: 0.92–0.67); the results during the validation period were also acceptable (NSE: 0.61–0.28). The results of this study are an important step in understanding the modeling behavior of these pesticides in SWAT and will help to identify thresholds of worst-case scenarios in order to assess the risk for the environment. - Highlights: • We performed a global LH-sensitivity analysis of all pesticide related parameters. • Key physical parameters are associated to percolation, degradation and sorption. • We simulated the measured loads of three different pesticides. • We performed an uncertainty analysis of all pesticide simulations. • All Pesticides differed considerably in their sensitivity and simulation behavior. - Pesticide load simulations of three pesticides were modeled by SWAT, providing clues on how to handle pesticides in future SWAT studies

  18. Carbamate Toxicity and Protective effect of vit. A and vit. E on some biochemicalaspects of male albino rats

    Directory of Open Access Journals (Sweden)

    Samir, A.M. Zaahkouk* ; Eman, G.E. Helal

    2000-12-01

    Full Text Available The effect of daily oral administration of carbamate (1/10 L.D50 on rats for 30 successive days were studied. The male rats were divided into five groups (control, control + oil, carbamate, carbamate + vit. A and carbamate + vit. E. Each group (except control and control + oil was daily administrated carbamate (0.012 mg/kg B.wt.. Two groups of carbamate ­ intoxicated animals provided with vit. A (700 mg/kg.B.wt or vit. E (10 mg/kg.B.wt. Poisoning symptoms were recorded, e.g. unbalanse, diarrhea, have poor health and posterior limbs rigidity. Haematological parameters showed a significant decrease in red blood corpuscles (R.B.Cs, white blood corpuscles (W.B.Cs count, Haemoglobin concentration and haematocrit value in groups treated with carbamate, and an improvement in these values was observed in groups treated with the anti-oxidants (vit. A and vit. E. Total lipids cholesterol, total proteins, albumin, glucose, LDH, AST, ALT, adrenaline and noradrenaline were measured in serum. Total proteins, total lipids, of tissues (liver, heart, muscle and kidney were investigated. The present study declare that, carbamate induced a significant elevetion in serum LDH, glucose. total lipids,cholesterol, AST, ALT, adrenaline and noradrenaline. On the other hand, causes a significant reduction in total proteins and albumin. The total lipids and total proteins of the tissue were recorded highly significant decrease in the group treated with carbamate only. From another point of view, antioxidant ameliorated the effect of carbamate on tissues. So, it is clear that administration of vit. E or vit. A. reduced the effect of carbamate on biochemical alteration to various extent. The antioxidant property of vitamin A and vitamin E seem to be responsible for the observed protection against carbamate intoxication.

  19. Pesticide Instrumental Analysis

    International Nuclear Information System (INIS)

    This workshop was the evaluation of the pesticides impact on the vegetable matrix with the purpose to determine the analysis by GC / M S. The working material were lettuce matrix, chard and a mix of green leaves and pesticides.

  20. Pesticides and Pregnancy

    Science.gov (United States)

    Pesticides and Pregnancy In every pregnancy, a woman starts out with a 3-5% chance of having ... risk. This sheet talks about whether exposure to pesticides may increase the risk for birth defects over ...

  1. Pesticide Product Label System

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Label System (PPLS) provides a collection of pesticide product labels (Adobe PDF format) that have been approved by EPA under Section 3 of the...

  2. Pesticide exposure - Indian scene

    International Nuclear Information System (INIS)

    Use of pesticides in India began in 1948 when DDT was imported for malaria control and BHC for locust control. India started pesticide production with manufacturing plant for DDT and benzene hexachloride (BHC) (HCH) in the year 1952. In 1958, India was producing over 5000 metric tonnes of pesticides. Currently, there are approximately 145 pesticides registered for use, and production has increased to approximately 85,000 metric tonnes. Rampant use of these chemicals has given rise to several short-term and long-term adverse effects of these chemicals. The first report of poisoning due to pesticides in India came from Kerala in 1958 where, over 100 people died after consuming wheat flour contaminated with parathion. Subsequently several cases of pesticide-poisoning including the Bhopal disaster have been reported. Despite the fact that the consumption of pesticides in India is still very low, about 0.5 kg/ha of pesticides against 6.60 and 12.0 kg/ha in Korea and Japan, respectively, there has been a widespread contamination of food commodities with pesticide residues, basically due to non-judicious use of pesticides. In India, 51% of food commodities are contaminated with pesticide residues and out of these, 20% have pesticides residues above the maximum residue level values on a worldwide basis. It has been observed that their long-term, low-dose exposure are increasingly linked to human health effects such as immune-suppression, hormone disruption, diminished intelligence, reproductive abnormalities, and cancer. In this light, problems of pesticide safety, regulation of pesticide use, use of biotechnology, and biopesticides, and use of pesticides obtained from natural plant sources such as neem extracts are some of the future strategies for minimizing human exposure to pesticides

  3. Kinetic and physicochemical properties of brain acetylcholinesterase from the peacock bass (Cichla ocellaris) and in vitro effect of pesticides and metal ions.

    Science.gov (United States)

    Silva, Kaline Catiely Campos; Assis, Caio Rodrigo Dias; Oliveira, Vagne Melo; Carvalho, Luiz Bezerra; Bezerra, Ranilson Souza

    2013-01-15

    Brain acetylcholinesterase (AChE; EC 3.1.1.7) from peacock bass (Cichla ocellaris) was characterized and the effect of organophosphorus and carbamate pesticides as well as ions and heavy metals was evaluated. The kinetic parameters K(m) and V(max) were determined as 0.769 mM and 0.189 U/mg of protein respectively. Optimal pH and temperature were found to be 8.0 and 45°C. The enzyme retained approximately half of the activity after incubation at 50°C for 30 min. Total cholinesterase activity on brain of this species can be ascribed to AChE according to selective inhibitors analysis (neostigmine, eserine and BW284c5 reduced its activity whereas no effect was noticed for Iso-OMPA). Seven pesticides (five organophosphates: dichlorvos, diazinon, chlorpyrifos, temephos, tetraethyl pyrophosphate - TEPP and two carbamates: carbaryl and carbofuran) showed inhibitory effects on C. ocellaris AChE. However, the strongest effect was observed with carbofuran (IC(50)=0.21 μM and K(i)=2.57 × 10(-3) μM). The following ions (1 mM) showed to inhibit its activity (decrescent order): Hg(2+)>As(3+)>Cu(2+)>Zn(2+). EDTA(2-) did not affect enzyme activity. The present study provides assay conditions and data to suggest this enzyme as in vitro biomarker of organophosphorus and carbamate pesticides in routine environmental screening programs. PMID:23220411

  4. Health Risk Assessment of Pesticide Residues via Dietary Intake of Market Vegetables from Dhaka, Bangladesh

    Directory of Open Access Journals (Sweden)

    Md. Shakhaoat Hossain

    2013-02-01

    Full Text Available The present study was designed to assess the health risk of pesticide residues via dietary intake of vegetables collected from four top agro-based markets of Dhaka, Bangladesh. High performance liquid chromatography with a photo diode array detector (HPLC-PDA was used to determine six organophosphorus (chlorpyrifos, fenitrothion, parathion, ethion, acephate, fenthion, two carbamate (carbaryl and carbofuran and one pyrethroid (cypermethrin pesticide residues in twelve samples of three common vegetables (tomato, lady’s finger and brinjal. Pesticide residues ranged from below detectable limit (<0.01 to 0.36 mg/kg. Acephate, chlorpyrifos, ethion, carbaryl and cypermethrin were detected in only one sample, while co-occurrence occurred twice for fenitrothion and parathion. Apart from chlorpyrifos in tomato and cypermethrin in brinjal, all pesticide residues exceeded the maximum residue limit (MRL. Hazard risk index (HRI for ethion (10.12 and carbaryl (1.09 was found in lady’s finger and tomato, respectively. Rest of the pesticide residues were classified as not a health risk. A continuous monitoring and strict regulation should be enforced regarding control of pesticide residues in vegetables and other food commodities.

  5. Toxic effects of pesticide mixtures at a molecular level: Their relevance to human health

    International Nuclear Information System (INIS)

    Highlights: ► Toxic effects of pesticide mixtures can be independent, dose addition or interaction. ► Metabolic interactions involve inhibition or induction of detoxifying enzymes. ► Organophosphates can potentiate pyrethroid, carbaryl and triazine toxicity. ► Synergism occurs when two active pesticides elicit greater than additive toxicity. ► Endocrine disruptors have the potential for additivity rather than synergism. - Abstract: Pesticides almost always occur in mixtures with other ones. The toxicological effects of low-dose pesticide mixtures on the human health are largely unknown, although there are growing concerns about their safety. The combined toxicological effects of two or more components of a pesticide mixture can take one of three forms: independent, dose addition or interaction. Not all mixtures of pesticides with similar chemical structures produce additive effects; thus, if they act on multiple sites their mixtures may produce different toxic effects. The additive approach also fails when evaluating mixtures that involve a secondary chemical that changes the toxicokinetics of the pesticide as a result of its increased activation or decreased detoxification, which is followed by an enhanced or reduced toxicity, respectively. This review addresses a number of toxicological interactions of pesticide mixtures at a molecular level. Examples of such interactions include the postulated mechanisms for the potentiation of pyrethroid, carbaryl and triazine herbicides toxicity by organophosphates; how the toxicity of some organophosphates can be potentiated by other organophosphates or by previous exposure to organochlorines; the synergism between pyrethroid and carbamate compounds and the antagonism between triazine herbicides and prochloraz. Particular interactions are also addressed, such as those of pesticides acting as endocrine disruptors, the cumulative toxicity of organophosphates and organochlorines resulting in estrogenic effects and the

  6. Biofilters to treat the pesticides wastes from spraying applications: results after 4 years of study.

    Science.gov (United States)

    Pigeon, O; De Vleeschouwer, C; Cors, F; Weickmans, B; Huyghebaert, B; Planchon, V; Pussemier, L; Culot, M

    2006-01-01

    Biofilters were developed in order to eliminate or reduce the quantity of pesticides from rinsing and cleaning waters of sprayers. Biofilters consist in 1, 2 or 3 plastic containers of 1 m3 placed in a vertical pile and containing a substrate elaborated from a homogenised mixture of local soil, chopped straw and compost able to absorb and degrade the pesticides. Biofilters are installed near the area for cleaning and rinsing the sprayer and the waste waters are pumped into the system. Since 2002, a pilot study is carried out in Belgium in order to evaluate the efficacy of these systems. Twenty pilot systems were installed since 2002 until 2004 in several farms, agricultural technical centres or schools and in a municipal maintenance service. The efficacy of the biofilters was studied for several chemical classes of herbicides (sulfonylurea, aryloxyalcanoic acids, chloroacetanilides), insecticides (pyrethroids, carbamates) and fungicides (dicarboximides, phenylamides, triazoles and strobilurines). The balance of the inputs and the outputs of the pesticides was determined by monitoring the elutes. The degradation kinetic of pesticides into the substrate was evaluated by analysing the pesticides into the substrate. The microbiological activity of the substrate was also evaluated by measuring respiration and some indirect parameters like dry matter content, Kjeldahl nitrogen content, organic carbon content and biological oxygen demand (BOD). Results obtained until now after four years of experiments have showed an overall good efficacy (retention) of pesticides by the biofilter and a high degradation rate for the majority of pesticides. Biofilters permit to reduce highly the quantity of pesticides from rinsing and cleaning waters of sprayers and contribute significantly to the reduction of the contamination of surface water. Biofilters are now registered by the Ministry of Agriculture and Environment of the Walloon Region in Belgium and are recommended to pesticides

  7. New synthesis of carbamate, thiocarbamate and urea type herbicides: preparation of 14C-labelled diuron and EPTC

    International Nuclear Information System (INIS)

    N,N-dialkyl-carbamic acid-trimethylsilyl-esters were synthesized starting with 14CO2. The new synthesis route is simple and provides good radiochemical yield. Silyl-carbaminates directly or through carbamoyl-halogenides may be used for preparation of labelled herbicides: carbamates, thiocarbamates and ureas. (author)

  8. Assessment of Acute Oral and Dermal Toxicity of 2 Ethyl-Carbamates with Activity against Rhipicephalus microplus in Rats

    Directory of Open Access Journals (Sweden)

    María Guadalupe Prado-Ochoa

    2014-01-01

    Full Text Available The acute oral and dermal toxicity of two new ethyl-carbamates (ethyl-4-bromophenyl-carbamate and ethyl-4-chlorophenyl-carbamate with ixodicide activity was determined in rats. The oral LD50 of each carbamate was 300 to 2000 mg/kg, and the dermal LD50 of each carbamate was >5000 mg/kg. Clinically, the surviving rats that had received oral doses of each carbamate showed decreased weight gain (P<0.05 and had slight nervous system manifestations. These clinical signs were evident from the 300 mg/kg dose and were reversible, whereas the 2000 mg/kg dose caused severe damage and either caused their death or was motive for euthanasia. At necropsy, these rats had dilated stomachs and cecums with diffuse congestion, as well as moderate congestion of the liver. Histologically, the liver showed slight degenerative lesions, binucleated hepatocytes, focal coagulative necrosis, and congestion areas; the severity of the lesions increased with dosage. Furthermore, an slight increase in gamma-glutamyltransferase, lactate dehydrogenase, and creatinine was observed in the plasma. The dermal application of the maximum dose (5000 mg/kg of each carbamate did not cause clinical manifestations or liver and skin alterations. This finding demonstrates that the carbamates under study have a low oral hazard and low acute dermal toxicity.

  9. Synthesis of methyl N-phenyl carbamate from dimethyl carbonate and 1,3-diphenyl urea under mild conditions

    Institute of Scientific and Technical Information of China (English)

    Jun Jie Gao; Hui Quan Li; Yi Zhang

    2007-01-01

    Synthesis of methyl N-phenyl carbamate from dimethyl carbonate and 1,3-diphenyl urea was investigated under atmospheric pressure. The results showed that homogenous catalyst sodium methoxide had the excellent activity to efficiently catalyze the synthesis of methyl N-phenyl carbamate under atmospheric pressure.

  10. Quality Control Of Selected Pesticides With GC

    International Nuclear Information System (INIS)

    The practical quality control of selected pesticides with GC is treated. Detailed descriptions are given on materials and methods used, including sample preparation and GC operating conditions. The systematic validation of multi methods is described, comprising performance characteristics in routine analysis, like selectivity, specificity etc. This is illustrated by chromatograms, calibration curves and tables derived from real laboratory data. (author)

  11. Pesticides and oncogenic modulation.

    Science.gov (United States)

    Vakonaki, Elena; Androutsopoulos, Vasilis P; Liesivuori, Jyrki; Tsatsakis, Aristidis M; Spandidos, Demetrios A

    2013-05-10

    Pesticides constitute a diverse class of chemicals used for the protection of agricultural products. Several lines of evidence demonstrate that organochlorine and organophosphate pesticides can cause malignant transformation of cells in in vitro and in vivo models. In the current minireview a comprehensive summary of recent in vitro findings is presented along with data reported from human population studies, regarding the impact of pesticide exposure on activation or dysregulation of oncogenes and tumor suppressor genes. Substantial mechanistic work suggests that pesticides are capable of inducing mutations in oncogenes and increase their transcriptional expression in vitro, whereas human population studies indicate associations between pesticide exposure levels and mutation occurrence in cancer-related genes. Further work is required to fully explore the exact mechanisms by which pesticide exposure affects the integrity and normal function of oncogenes and tumor suppressor genes in human populations.

  12. The carcinogenic potential of ethyl carbamate (urethane): risk assessment at human dietary exposure levels

    OpenAIRE

    Schlatter, J; Werner K Lutz

    2012-01-01

    Ethyl carbamate is found in fermented foods: bread contains 3-15 ng/g, stone-fruit brandies 200-20,000 ngfg, and about one-third of table-wine samples analysed contained more than 10 ng/g. In animals, ethyl carbamate is degraded to C02, H20 and NH3, with intermediate formation ofethanol. This degradation has been shown tobe inhibited (postponed) in the mouse by ethanol concentrations in the blood of about 0.15% and higher. A quantitatively minor pathway involves a two-step oxidation of the et...

  13. Control of Pesticides 2000

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Three different groups of products covered by the pesticide regulation have been included in the 2000 analytical chemical authority control: 1) herbicides containing aclonifen, clopyralid, dicamba, quinoclamine, bromoxynil, ioxynil, simazine, and terbuthylazine. 2) Fungicides containing fenpropidin......, fluazinam, and kresoxim-methyl, and among insecticides containing fenazaquin. Thus, all the eighteen analysed samples of these pesticides complied with the accepted tolerances with respect to content of active ingredients set by the Danish regulation of pesticides. The only product containing buprofezin...

  14. Pesticides and childhood cancers.

    OpenAIRE

    Daniels, J L; Olshan, A.F.; Savitz, D A

    1997-01-01

    To evaluate the possible association between pesticides and the risk of childhood cancers, epidemiologic studies published between 1970 and 1996 were critically reviewed. Thirty-one studies investigated whether occupational or residential exposure to pesticides by either parents or children was related to increased risk of childhood cancer. In general, the reported relative risk estimates were modest. Risk estimates appeared to be stronger when pesticide exposure was measured in more detail. ...

  15. Pesticides (Environmental Health Student Portal)

    Science.gov (United States)

    ... Pesticides Climate Change Climate Change Home What is Climate Change ... Pesticides The Basics Pesticides are substances we use to control or kill pests. Pests can be weeds, insects, rodents, or bacteria — anything we don’t want ...

  16. Optical Biosensor with Multienzyme System Immobilized onto Hybrid Membrane for Pesticides Determination

    Directory of Open Access Journals (Sweden)

    Lyubov Yotova

    2011-12-01

    Full Text Available A construction of optical biosensor based on simultaneous immobilization of acetylcholinesterase and choline oxidase enzymes for the detection of pesticides residues is described. Different kinds of novel SiO2 hybrid membranes were synthesized to be suitable for optical biosensors using sol-gel techniques. The bioactive component of the sensor consists of a multi-enzyme system including acetylcholinesterase and choline oxidase covalently immobilized on new hybrid membranes. The sensor exhibited a linear response to acetylcholine in a concentration range of 2.5 - 30 mM. Inhibition plots obtained from testing carbamate (carbofuran pesticides exhibited concentration dependent behaviour and showed linear profiles in concentration ranges between 5x10-8 - 5x10-7 M for carbofuran. The factors affecting the constructed optical biosensors were investigated.

  17. Comparative toxicity of the pesticides carbofuran and malathion to the freshwater flagellate Euglena gracilis.

    Science.gov (United States)

    Azizullah, Azizullah; Richter, Peter; Häder, Donat-Peter

    2011-08-01

    Pesticides are toxic chemicals used for agricultural as well as non-agricultural purposes. The toxicity of pesticides does not remain limited to the site of application but they also cause toxicity to non-target organisms in terrestrial as well as in aquatic environments. This study discusses the comparative toxicity of a carbamate (carbofuran) and an organophosphorus (malathion) pesticide to the freshwater flagellate Euglena gracilis during short- and long-term exposures. To evaluate the toxicity of the pesticides, different parameters of the flagellate, like cell density, motility, swimming velocity, cell shape, gravitactic orientation, photosynthetic efficiency, and concentration of light harvesting pigments, were used as end points. Carbofuran was found to be more toxic to E. gracilis than malathion and adversely affected almost all the tested parameters in short- and long-term experiments. The only significant adverse effect by malathion could be demonstrated on the swimming velocity of cells in short-term experiments. The adverse effects of the pesticides were more pronounced during short-term than during long-term exposure.

  18. Improved indicators and monitoring of pesticide use

    DEFF Research Database (Denmark)

    Sørensen, Peter Borgen; Kjær, Christian; Kudsk, Per;

      The goal for the new improved indicator, PestNaB (Pesticiders NaturBelastning), was to develop a valid indicator reflecting the potential risk for nature due to application of pesticides and based on available data set for Danish conditions. The focus is on risk in relation the nature close to......, and directly inside, the agricultural areas so this excludes the risk for contamination of groundwater and the human risk. Elements from existing indicators are combined in a way that can make optimal use of the available data, where the level of complexity is adjusted to fit the conditions of uncertainty...

  19. Pesticide management and their residues in sediments and surface and drinking water in the Mekong Delta, Vietnam.

    Science.gov (United States)

    Toan, Pham Van; Sebesvari, Zita; Bläsing, Melanie; Rosendahl, Ingrid; Renaud, Fabrice G

    2013-05-01

    Public concern in Vietnam is increasing with respect to pesticide pollution of the environment and of drinking water resources. While established monitoring programs in the Mekong Delta (MD) focus on the analysis of organochlorines and some organophosphates, the environmental concentrations of more recently used pesticides such as carbamates, pyrethroides, and triazoles are not monitored. In the present study, household level pesticide use and management was therefore surveyed and combined with a one year environmental monitoring program of thirteen relevant pesticides (buprofezin, butachlor, cypermethrin, α-endosulfan, β-endosulfan, endosulfan-sulfate, fenobucarb, fipronil, isoprothiolane, pretilachlor, profenofos, propanil, and propiconazole) in surface water, soil, and sediment samples. The surveys showed that household level pesticide management remains suboptimal in the Mekong Delta. As a consequence, a wide range of pesticide residues were present in water, soil, and sediments throughout the monitoring period. Maximum concentrations recorded were up to 11.24 μg l(-1) in water for isoprothiolane and up to 521 μg kg(-1) dm in sediment for buprofezin. Annual average concentrations ranged up to 3.34 μg l(-1) in water and up to 135 μg kg(-1) dm in sediment, both for isoprothiolane. Occurrence of pesticides in the environment throughout the year and co-occurrence of several pesticides in the samples indicate a considerable chronic exposure of biota and humans to pesticides. This has a high relevance in the delta as water for drinking is often extracted from canals and rivers by rural households (GSO, 2005, and own surveys). The treatment used by the households for preparing surface water prior to consumption (flocculation followed by boiling) is insufficient for the removal of the studied pesticides and boiling can actually increase the concentration of non-volatile pollutants. PMID:23500396

  20. Pesticide management and their residues in sediments and surface and drinking water in the Mekong Delta, Vietnam.

    Science.gov (United States)

    Toan, Pham Van; Sebesvari, Zita; Bläsing, Melanie; Rosendahl, Ingrid; Renaud, Fabrice G

    2013-05-01

    Public concern in Vietnam is increasing with respect to pesticide pollution of the environment and of drinking water resources. While established monitoring programs in the Mekong Delta (MD) focus on the analysis of organochlorines and some organophosphates, the environmental concentrations of more recently used pesticides such as carbamates, pyrethroides, and triazoles are not monitored. In the present study, household level pesticide use and management was therefore surveyed and combined with a one year environmental monitoring program of thirteen relevant pesticides (buprofezin, butachlor, cypermethrin, α-endosulfan, β-endosulfan, endosulfan-sulfate, fenobucarb, fipronil, isoprothiolane, pretilachlor, profenofos, propanil, and propiconazole) in surface water, soil, and sediment samples. The surveys showed that household level pesticide management remains suboptimal in the Mekong Delta. As a consequence, a wide range of pesticide residues were present in water, soil, and sediments throughout the monitoring period. Maximum concentrations recorded were up to 11.24 μg l(-1) in water for isoprothiolane and up to 521 μg kg(-1) dm in sediment for buprofezin. Annual average concentrations ranged up to 3.34 μg l(-1) in water and up to 135 μg kg(-1) dm in sediment, both for isoprothiolane. Occurrence of pesticides in the environment throughout the year and co-occurrence of several pesticides in the samples indicate a considerable chronic exposure of biota and humans to pesticides. This has a high relevance in the delta as water for drinking is often extracted from canals and rivers by rural households (GSO, 2005, and own surveys). The treatment used by the households for preparing surface water prior to consumption (flocculation followed by boiling) is insufficient for the removal of the studied pesticides and boiling can actually increase the concentration of non-volatile pollutants.

  1. Pesticide Product Information System (PPIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Information System contains information concerning all pesticide products registered in the United States. It includes registrant name and...

  2. Exposure to Pesticides in Residents or the Banks of the Río Bogotá (Suesca and the Capitan Fish

    Directory of Open Access Journals (Sweden)

    Rodríguez-Forero Adriana

    2012-03-01

    Full Text Available Objective: Considering the high use of pesticides in Colombia and the harmful effects resulting fromexposure to these substances on human health and the environment, a study for the determinationof biomarkers of exposure and effect of pesticides in population of the banks of the Río Bogotáin Suesca, the levels of pesticides in river water samples taken in the same city and in samples offish, “Capitán de la Sabana” (Eremophylus mutisii caught in this area. Materials and methods:We measured for organophosphates, carbamates, dithiocarbamates and organochlorines. We alsoexplored through a survey of occupational exposure to pesticides in the population and knowledgeand use of personal protective measures in their work. Additionally, we explored the habit offishing for captain and consumption in the diet of the inhabitants of the riverbank. Results: Theresults show the presence of organochlorine and organophosphorus pesticides in the river and infish tissue and organochlorine and ethylene thiourea in human biological samples. Participated inthe study workers directly exposed to pesticides, highly toxic handlers, most know and use personalprotective measures and industrial hygiene. Conclusions: Pollution such as pesticides in the upperbasin of Bogotá that affects wildlife and coastal populations. Best action is necessary to promoteenvironmental care, protection and self-care of persons using pesticides in the area.

  3. Pesticide Sector Performed Well

    Institute of Scientific and Technical Information of China (English)

    Wang Lvxian

    2007-01-01

    @@ 1 Further output growth in the first half of 2007 According to data from the National Bureau of Statistics of China, the output of pesticides (usually refering to pure pesticide technical) in China was 856 thousand tons in the first half of 2007, an increase of 25.6% over the same period of 2006.

  4. Pesticider 2 i overfladevand

    DEFF Research Database (Denmark)

    Nyeland, B.; Kvamm, B. L.

    DMU har den 29. september 1999 afholdt en metodeafprøvning: Pesticider 2 i overfladevand. Der var tilmeldt 17 danske og udenlandske laboratorier i metodeafprøvningen. Prøvningen omfattede 32 pesticider i overfladevand fra en sjællandsk sø. Koncentrationsniveauet for hver komponent var på 0,025 - 0...

  5. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  6. Screening Pesticides for Neuropathogenicity

    OpenAIRE

    Doherty, John D.

    2006-01-01

    Pesticides are routinely screened in studies that follow specific guidelines for possible neuropathogenicity in laboratory animals. These tests will detect chemicals that are by themselves strong inducers of neuropathogenesis if the tested strain is susceptible relative to the time of administration and methodology of assessment. Organophosphate induced delayed neuropathy (OPIDN) is the only known human neurodegenerative disease associated with pesticides and the existing...

  7. BETA-GLUCURONYL CARBAMATE BASED PRO-MOIETIES DESIGNED FOR PRODRUGS IN ADEPT

    NARCIS (Netherlands)

    LEENDERS, RGG; GERRITS, KAA; RUIJTENBEEK, R; SCHEEREN, HW; Haisma, Hidde; BOVEN, E

    1995-01-01

    A number of pro-moieties 8a - e designed for prodrug preparation have been synthesized (chart 2). The pro-moieties, containing a glucuronyl carbamate group linked to a spacer possessing a terminal carboxylic acid group, have been synthesized from isocyanates 6 and anomerically unprotected glucuronic

  8. Evaluation of ethyl N-(2-phenethyl) carbamate analogues as biofilm inhibitors of methicillin resistant Staphylococcus aureus.

    Science.gov (United States)

    Stephens, Matthew D; Yodsanit, Nisakorn; Melander, Christian

    2016-07-12

    A small molecule library consisting of 45 compounds was synthesized based on the bacterial metabolite ethyl N-(2-phenethyl) carbamate. Screening of the compounds revealed a potent analogue capabale of inhibiting several strains of Methicillin Resistant S. aureus biofilms with low to moderate micromolar IC50 values. PMID:27341658

  9. Carbamate Stabilities of Sterically Hindered Amines from Quantum Chemical Methods: Relevance ofr CO2 Capture

    NARCIS (Netherlands)

    Gangarapu, S.; Marcelis, A.T.M.; Zuilhof, H.

    2013-01-01

    The influence of electronic and steric effects on the stabilities of carbamates formed from the reaction of CO2 with a wide range of alkanolamines was investigated by quantum chemical methods. For the calculations, B3LYP, M11-L, MP2, and spin-component-scaled MP2 (SCS-MP2) methods were used, coupled

  10. The dissociation chemistry of ionized methyl carbamate and its isomers revisited: Theory and experiment in concert

    NARCIS (Netherlands)

    P.C. Burgers (Peter); G.A. McGibbon (Graham); K.J. Jobst (Karl)

    2012-01-01

    textabstractEarly combined computational and experimental studies by J.K. Terlouw and colleagues propose that low-energy methyl carbamate ions, NH 2COOCH 3 •+ (MC-1), rearrange into distonic ions NH 2C(OH)OCH 2 •+ and hydrogen-bridged radical cations [NH 2C=O-H-OCH 2] •+ (MC-5) en route to the obser

  11. The Use and Effect of Carbamate Insecticide on Animal Health and Products

    Directory of Open Access Journals (Sweden)

    Indraningsih

    2008-06-01

    Full Text Available The use of carbamate in Indonesia is relatively new, in particular after prohibition on the use of most organochlorines (OC. Carbamates that commonly used for agricultural activities are carbofuran (Furadan, aldicarb (Temik and carbaryl (Sevin. When properly used, they will provide benefit, but misuse of insecticides would affect productivity, poisoning, public health problems, environmental contamination and residues in foods. A monitoring result of carbamate used in Java indicates that carbofurans were detected in soils (0,8 – 56,3 ppb; water (0,1 – 5,0 ppb; rice (nd – 5,0 ppb; soybeans (1,2 – 610 ppb; animal feed (12 – 102 ppb; beef (110 – 269 ppb; and sera of beef cattle (167 – 721 ppb. The residue level was above the maximum residue limits (MRL released by Indonesian Standardization Agency (Badan Standardisasi Nasional in some samples. The presence of carbofuran in foods should be taken into account since the carbofuran is regarded highly toxic for public and animal health. This paper describes the toxicity of carbamate, clinical signs of poisoning, residue in foods and environment, handling of poisoning and residue control.

  12. Design, synthesis, and evaluation of carbamate-substituted analogues of (+)-discodermolide.

    Science.gov (United States)

    Smith, Amos B; Freeze, B Scott; Lamarche, Matthew J; Hirose, Tomoyasu; Brouard, Ignacio; Rucker, Paul V; Xian, Ming; Sundermann, Kurt F; Shaw, Simon J; Burlingame, Mark A; Horwitz, Susan Band; Myles, David C

    2005-01-20

    [Structure: see text] The design, syntheses, and biological evaluation of 22 totally synthetic analogues of the potent microtubule-stabilizing agent (+)-discodermolide (1) have been achieved. Structure-activity relationships of the C(19) carbamate were defined, exploiting two synthetically simplified scaffolds, as well as the parent (+)-discodermolide framework.

  13. 76 FR 34147 - Land Disposal Restrictions: Revision of the Treatment Standards for Carbamate Wastes

    Science.gov (United States)

    2011-06-13

    ... glycol, dicarbamate U404 Triethylamine U409 Thiophanate-methyl U410 Thiodicarb U411 Propoxur It also... carbamates (61 FR 15583). These treatment standards were based on data for similar wastes for which EPA promulgated UTS in1994 (59 FR 47982) and on analytical detection limits compiled from sampling and...

  14. Computational study of structural properties of lithium cation complexes with carbamate-modified disiloxanes.

    Science.gov (United States)

    Jeschke, Steffen; Wiemhöfer, Hans-Dieter; Mück-Lichtenfeld, Christian

    2014-07-21

    Lithium cation solvation structures [Li(S)(n=1-4)](+) with ligands of cyclic or noncyclic carbamate-modified disiloxanes are optimized at B3LYP level of theory and compared to their corresponding simplified carbamates and to the organic carbonates ethylene carbonate (EC) and dimethyl carbonate (DMC). The electrostatic potentials (ESP) of these investigated carbonyl-containing solvents are mapped on the electron density surface. The maximum ESP is located at the C=O-oxygen, whereas the disiloxane functionality represents an unpolar residue. Natural Bond Orbitals (NBO) analysis reveals strong n(N) →π(C[double bond, length as m-dash]O) donor-acceptor interactions in carbamates which outrun dipolar properties. As a result, higher total binding energies (ΔE(B)) for solvation of Li(+) in carbamates (-148 kcal mol(-1)) are found than for carbonates (-137 kcal mol(-1)). Furthermore, the disiloxane moiety with its Si-O bond is stabilized by n(O) →σ*(Si-C) hyperconjugation that provides additional electron density to a nearby SiCH3 methyl group thus supporting an additional SiCH2-H...Li(+) coordination. The formation of all investigated solvation structures is exothermic. Owing to steric hindrance of noncyclic carbonyl-containing ligands and the bulky disiloxane functionality, the solvation structure [Li(S)3](+) is the preferred structure according to Gibbs free energy ΔG(B) results. PMID:24914737

  15. Light Induced C-C Coupling of 2-Chlorobenzazoles with Carbamates, Alcohols, and Ethers.

    Science.gov (United States)

    Lipp, Alexander; Lahm, Günther; Opatz, Till

    2016-06-01

    A light induced, transition-metal-free C-C coupling reaction of 2-chlorobenzazoles with aliphatic carbamates, alcohols, and ethers is presented. Inexpensive reagents, namely sodium acetate, benzophenone, water, and acetonitrile, are employed in a simple reaction protocol using a cheap and widely available 25 W energy saving UV-A lamp at ambient temperature. PMID:27128627

  16. Control of Pesticides 2001

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    The analytical chemical authority control on pesticide products on the Danish market performed in 2001 is reported. Samples of selected groups of pesticides have been collected from the market and analysed to verify whether the actual contents of the respective active ingredients in the products...... comply with the label-claimed content. The tolerance of deviation from the label-claimed content of active ingredient is set by the Danish pesticide regulation. Three different groups of products covered by the pesticide regulation have been included in the 2001 analytical chemical authority control: 1....... Satisfactory results were found among herbicides containing pendimethalin and methabenzthiazuron, among fungicides containing azaconazole, tolylfluanid, propamocarb and cyprodinil, and among insecticides containing amitraz, phosalone and diflubenzuron. Thus, the twelve analysed samples of these pesticides...

  17. PESTICIDES: BENEFITS AND HAZARDS

    Directory of Open Access Journals (Sweden)

    Ivan Maksymiv

    2015-05-01

    Full Text Available Pesticides are an integral part of modern life used to prevent growth of unwanted living  organisms. Despite the fact that scientific statements coming from many toxicological works provide indication on the low risk of the pesticides and their residues, the community especially last years is deeply concerned about massive application of pesticides in diverse fields. Therefore evaluation of hazard risks particularly in long term perspective is very important. In the fact there are at least two clearly different approaches for evaluation of pesticide using: the first one is defined as an objective or probabilistic risk assessment, while the second one is the potential economic and agriculture benefits. Therefore, in this review the author has considered scientifically based assessment of positive and negative effects of pesticide application and discusses possible approaches to find balance between them.

  18. Effect Of Fenugreek Seed Powder In Toxicity Induced By MALAPHOS And METHAVINE Pesticides In Male Rats

    International Nuclear Information System (INIS)

    Pesticides administration to rats led to an enhancement in oxidative stress and generation of free radicals. These free radicals may be involved in the toxicity of some pesticides. Therefore, the present study was undertaken to assess the effect of pre-treatment of rats with fenugreek seed powder at the dose level of 250 mg/kg b.wt in inhibiting the oxidative damage induced by administration malaphos (organophosphorus) at the dose level of 343.75 mg/kg b.wt and methavine (carbamate) at the dose level of 4 mg/kg b.wt for 6 weeks. Also the present study was carried out to evaluate the strength of fenugreek seed powder and the influence of both pesticides, malaphos and methovine on serum glucose, insuline, total bilirubin, total protein, albumin and gamma glutamyl transferase (γGT), calcium (Ca), inorganic phosphorus and iron (Fe) contents. The metabolism of14C-glucose injected 24 hours post-treatments with the two pesticides and fenugreek seed powder were studied. The results obtained demonstrated that the deleterious damage due to malaphos and methavine administration was manifested by the significant elevation in serum glucose, gamma glutamyl transferase (γ -GT), calcium (Ca), and iron content. Also, there was significant decrease in insulin level, total bilirubin, total protein, albumin and inorganic phosphorus. On the other hand, the data recorded a reduction in the tracing of metabolizable of14C- glucose which was more pronounced in urine of rats administrated malaphos compared to those received methavine pesticide. It could be concluded that administration of fenugreek seed powder (FSP) to rats during the treatment with malaphos or methavine pesticide attenuated to a great extent the damaging effects of both pesticides on the here in assayed parameters. According, by fenugreek administration at the used dose may have an indirect physiological effect on the metabolism of14C- glucose.

  19. Health Risk Assessment of Pesticide Usage in Menia El-Kamh Province of Sharkia Governorate in Egypt

    Directory of Open Access Journals (Sweden)

    Jean-Claude Assad

    2002-10-01

    Full Text Available Abstract: Menia El-Kamh province of the Sharkia Governorate constitutes one of the largest agricultural areas in Egypt. About 88% of the nearly 472,000 people living in this province rely on agricultural activities for subsistence. Several pesticides including organochloride, organophosphorus, carbamate, and pyrethroid insecticides, fungicides, and herbicides are commonly used in citrus, vegetable and other crop-growing areas to increase agricultural productivity. However, their use has also been associated with several cases of pesticide poisoning. In this research, we conducted a field survey to assess the knowledge, attitudes, and practices of the farmer’s community regarding the safe use of pesticides. We also evaluated the residual concentrations of selected pesticides in water, soil, milk, fish, and orange samples, and estimated the potential health risks associated with the exposure to these pesticides. Data obtained from the field survey indicate that more than 95% of farm workers do not practice safety precautions during pesticide formulation and application; leading to a considerable prevalence of pesticide-related illnesses in this agricultural community. Pesticide residues in various environmental samples varied greatly; from below detection levels (3-5 ng to as high as 325 ppb depending on the matrix of interest, and the specific pesticide of concern. The analysis of health risk estimates indicated that chlorpyrifos, DDT, dimethoate, methomyl, and larvin did not pose a direct hazard to human health, although present in water, milk, orange, and/or fish. However, aldicarb, and carbosulfan levels exceeded the reference doses, indicating a great potential for systemic toxicity, especially in children who are considered to be the most vulnerable population subgroup. The upper-bound values of cancer risk from DDT exposure were estimated to be about 8 (adults, and 55 (children excess cancers in a population of one million.

  20. Presence of organophosphorus pesticide oxygen analogs in air samples

    OpenAIRE

    Armstrong, Jenna L.; Fenske, Richard A; Yost, Michael G.; Galvin, Kit; Tchong-French, Maria; Yu, Jianbo

    2013-01-01

    A number of recent toxicity studies have highlighted the increased potency of oxygen analogs (oxons) of several organophosphorus (OP) pesticides. These findings were a major concern after environmental oxons were identified in environmental samples from air and surfaces following agricultural spray applications in California and Washington State. This paper reports on the validity of oxygen analog measurements in air samples for the OP pesticide, chlorpyrifos. Controlled environmental and lab...

  1. A study of neurologic symptoms on exposure to organophosphate pesticides in the children of agricultural workers

    Directory of Open Access Journals (Sweden)

    Rastogi S

    2010-01-01

    Full Text Available Pesticides are used extensively throughout the world in agriculture and in pest control as well as for community health purposes. Organophosphate (OP pesticide self-poisoning is an important clinical problem in rural regions of the developing world that kills an estimated 200,000 people every year. Unintentional poisoning kills far fewer people but is an apparent problem in places where highly toxic OP pesticides are available. Neurologic dysfunction is the best documented health effect of pesticide exposure. High-level exposure has both acute and long-term neurologic signs and symptoms, and adverse effects have been reported in most type of pesticides, including organophosphate (OP, carbamate, organochlorine, and pyrethroid insecticides, herbicides, fungicides, and fumigants. Acute OP pesticide exposure can involve in wide range of both central and peripheral neurologic symptoms. Increased neurologic symptom prevalence may provide early evidence of neurologic dysfunctions, before clinically measurable signs are evident. In this study, we analyzed the cross-sectional data on neurologic signs and symptoms from 225 rural children, both males (n = 132 and females (n = 93 who were occupationally and paraoccupationally exposed to methyl OPs (dichlorvos, fenthion, malathion, methyl parathion and ethyl OPs (chlorpyrifos, diazinon, ethyl parathion as they belonged to agricultural families handling, mixing, and spraying the OP pesticides. The children completed a specially designed questionnaire (Q16 on neurologic symptoms associated with pesticide exposure with their parental help. A suitable reference group consisting of rural children (n = 50 never involved in pesticide handling (neither outdoor nor indoor belonging to similar socioeconomic strata included in the study to compare the prevalence of various neurologic symptoms between the two groups. Among all the neurologic self-reported symptoms, headache, watering in eyes, and burning sensation in

  2. Modulation of macrophage functionality induced in vitro by chlorpyrifos and carbendazim pesticides.

    Science.gov (United States)

    Helali, Imen; Ferchichi, Saiida; Maaouia, Amal; Aouni, Mahjoub; Harizi, Hedi

    2016-09-01

    The immune response is the first defense against pathogens; however, it is very sensitive and can be impacted on by agrochemicals such as carbamate and organophosphate pesticides widely present in the environment. To understand how pesticides can affect immune cell function in vitro, this study investigated the effects of chlorpyrifos (CPF) and carbendazim (CBZ), the most commonly used pesticides worldwide, on murine immune cell (i.e. macrophage) functions, including lysosomal enzyme activity and pro-inflammatory cytokines (IL-1β and TNFα) and nitric oxide (NO) production by isolated mouse peritoneal macrophages. This study showed for the first time that CPF and CBZ dose-relatedly reduced macrophage lysosomal enzyme activity and LPS-induced production of IL-1β, TNFα and NO. In general, the effects caused by CPF appeared more pronounced than those by CBZ. Collectively, these results demonstrated that CPF and CBZ exhibited marked immunomodulatory effects and could act as potent immunosuppressive factors in vitro. This inhibition of macrophage pro-inflammatory function may be an integral part of the underlying mode of action related to pesticide-induced immunosuppression. PMID:27429139

  3. Health risks of employees working in pesticide retail shops: An exploratory study

    Directory of Open Access Journals (Sweden)

    Kesavachandran C

    2009-01-01

    Full Text Available Background: Shop keepers dealing with pesticides are exposed to multiple pesticides that include organophosphates, organochlorines, carbamates, pyrethroids. Hence an exploratory health study was conducted on shopkeepers selling pesticides in urban areas of Lucknow and Barabanki District, Uttar Pradesh, India. Materials and Methods: Detailed information regarding socio-economic status, family history, personal habits and work practices were recorded for 20 subjects and controls by the investigator on a pre-tested questionnaire. Clinical examination including neurological studies of the shopkeepers and control subjects was done. Results: The study revealed significant slowing of motor nerve conduction velocity and low peak expiratory flow rate among shopkeepers as compared to control subjects. Prevalence of significantly higher gastro-intestinal problems was also observed among exposed subjects. Neurological, ocular, cardiovascular and musculo-skeletal symptoms were also found to be higher among shopkeepers. This was not statistically significant. Significantly higher relative risk for sickness related to systems viz., cardio-vasular, genito-urinary, respiratory, nervous and dermal was observed among exposed subjects compared to controls. Conclusions: These findings provide a prima facie evidence of clinical manifestations because of multiple exposures to pesticides and poor safety culture at work place.

  4. The Danish Pesticide Tax

    DEFF Research Database (Denmark)

    Pedersen, Anders Branth; Nielsen, Helle Ørsted; Andersen, Mikael Skou

    2015-01-01

    This case study analyses the effects of the Danish pesticide tax (1996-2013) on agriculture which was introduced as an ad valorem tax in 1996, doubled in 1998, and redesigned in 2013 as a tax based on the toxicity of the pesticides. The Danish pesticide taxes probably represent the world’s highest...... pesticide taxes on agriculture, which makes it interesting to analyze how effective they have been. Here the effects of the ad valorem tax (1996-2013) are analyzed. The case study demonstrates the challenges of choosing an optimal tax design in a complex political setting where, additionally, not all...... individuals in the target group necessarily react to the economic incentives as predicted by economic modeling. It also demonstrates that a small first green-tax-step over time might develop into a better tax design....

  5. Pesticide-Exposure Matrix

    Science.gov (United States)

    The "Pesticide-exposure Matrix" was developed to help epidemiologists and other researchers identify the active ingredients to which people were likely exposed when their homes and gardens were treated for pests in past years.

  6. Pesticide Registration Information System

    Data.gov (United States)

    U.S. Environmental Protection Agency — PRISM provides an integrated, web portal for all pesticide related data, communications, registrations and transactions for OPP and its stakeholders, partners and...

  7. Intensification of degradation of methomyl (carbamate group pesticide) by using the combination of ultrasonic cavitation and process intensifying additives.

    Science.gov (United States)

    Raut-Jadhav, Sunita; Pinjari, Dipak V; Saini, Daulat R; Sonawane, Shirish H; Pandit, Aniruddha B

    2016-07-01

    In the present work, the degradation of methomyl has been carried out by using the ultrasound cavitation (US) and its combination with H2O2, Fenton and photo-Fenton process. The study of effect of operating pH and ultrasound power density has indicated that maximum extent of degradation of 28.57% could be obtained at the optimal pH of 2.5 and power density of 0.155 W/mL. Application of US in combination with H2O2, Fenton and photo-Fenton process has further accelerated the rate of degradation of methomyl with complete degradation of methomyl in 27 min, 18 min and 9 min respectively. Mineralization study has proved that a combination of US and photo-Fenton process is the most effective process with maximum extent of mineralization of 78.8%. Comparison of energy efficiency and cost effectiveness of various processes has indicated that the electrical cost of 79892.34Rs./m(3) for ultrasonic degradation of methomyl has drastically reduced to 2277.00Rs./m(3), 1518.00Rs./m(3) and 807.58Rs./m(3) by using US in combination with H2O2, Fenton and photo-Fenton process respectively. The cost analysis has also indicated that the combination of US and photo-Fenton process is the most energy efficient and cost effective process.

  8. A study on the effects of golf course organophosphate and carbamate pesticides on endangered, cave-dwelling arthropods Kauai, Hawaii

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Three endemic species, two arthropods and one isopod, are present in the Kauai caves. These species are critical components of the cave ecosystems and are possibly...

  9. Intensification of degradation of methomyl (carbamate group pesticide) by using the combination of ultrasonic cavitation and process intensifying additives.

    Science.gov (United States)

    Raut-Jadhav, Sunita; Pinjari, Dipak V; Saini, Daulat R; Sonawane, Shirish H; Pandit, Aniruddha B

    2016-07-01

    In the present work, the degradation of methomyl has been carried out by using the ultrasound cavitation (US) and its combination with H2O2, Fenton and photo-Fenton process. The study of effect of operating pH and ultrasound power density has indicated that maximum extent of degradation of 28.57% could be obtained at the optimal pH of 2.5 and power density of 0.155 W/mL. Application of US in combination with H2O2, Fenton and photo-Fenton process has further accelerated the rate of degradation of methomyl with complete degradation of methomyl in 27 min, 18 min and 9 min respectively. Mineralization study has proved that a combination of US and photo-Fenton process is the most effective process with maximum extent of mineralization of 78.8%. Comparison of energy efficiency and cost effectiveness of various processes has indicated that the electrical cost of 79892.34Rs./m(3) for ultrasonic degradation of methomyl has drastically reduced to 2277.00Rs./m(3), 1518.00Rs./m(3) and 807.58Rs./m(3) by using US in combination with H2O2, Fenton and photo-Fenton process respectively. The cost analysis has also indicated that the combination of US and photo-Fenton process is the most energy efficient and cost effective process. PMID:26964933

  10. Development of an analytical strategy based on LC-MS/MS for the measurement of different classes of pesticides and theirs metabolites in meconium: application and characterisation of foetal exposure in France.

    Science.gov (United States)

    Berton, Thierry; Mayhoub, Flora; Chardon, Karen; Duca, Radu-Corneliu; Lestremau, Francois; Bach, Véronique; Tack, Karine

    2014-07-01

    It is important to evaluate the impact of pesticides on human health because exposure to these compounds has been linked to harmful effects in many research studies. This exposure may be particularly harmful during the early stages of development (e.g. the prenatal period). The aim of the present study was to develop an analytical strategy for quantifying a number of pesticides and their metabolites in meconium (the neonate's first faeces), in order to characterize the extent of foetal exposure. The meconium sample was dried and grinded in order to homogenize the sample, prior to solid-liquid extraction and a purification by solid-phase extraction using a weak anion mixed-mode polymeric sorbent. Analyte separation and quantification was performed by liquid chromatography coupled to electrospray-triple quadrupole mass spectrometry. Five pesticide families (carbamates, organophosphates, pyrethroids, phenylureas and phenoxy herbicides) and their metabolites could be quantified in meconium with limits of quantification ranging between 0.2 ng/g and 200 ng/g. This method was applied to a set of 171 meconium samples collected in the Picardie region of northern France. The highest prevalence was observed for metabolites of organophosphates and carbamates (57.9% and 22.8%, respectively). The parent pesticides were rarely present and were only found at very low concentrations, except for the pyrethroids cyfluthrin and cypermethrin, which were found in 7.6% of meconium samples at concentrations of between 43.8 and 480 ng/g. The most frequently detected contaminant was the organophosphate metabolite dimethyl thiophosphate detected in 49.1% of the samples and quantified with a median concentration of 344 ng/g. These data evidence significant foetal exposure to organophosphate pesticides, pyrethroids and carbamates.

  11. Quantitative analysis of ethyl carbamate in Korean alcoholic beverages by chromatography with mass selective detection

    Energy Technology Data Exchange (ETDEWEB)

    Park, G.B.; Lee, S.G. [Korea Research Institute of Chemical Technology, Taejon (Korea)

    2002-02-01

    In order to determine the contents of ethyl carbamate in Korean traditional alcoholic beverages and general beverages, GC/MS-SIM method was used after extraction of beverages with dichloromethane. The contents of ethyl carbamate in Korean traditional alcoholic beverages, non-distilled alcohol, and whisky were detected in the rage of 4.6-50.2 {mu}g/L, 27.8-45.4 {mu}g/L, and 24.8-55.1 {mu}g/L, respectively. The recoveries were ranged from 83.3 to 104.8 %. The values of relative standard deviation were ranged from 1.8 to 14.8% and the detection limit was 0.3 {mu}g/L. (author). 13 refs., 2 tabs., 4 figs.

  12. Sulfonamide and carbamate derivatives of 6-chloropurine: synthesis, characterization and antimicrobial activity evaluation

    Directory of Open Access Journals (Sweden)

    K. Venkata Narayana

    2016-07-01

    Full Text Available A series of new sulfonamide derivatives, 9-(substitutedbenzenesulfonyl-6-chloro-9H-purines 7(a-e and carbamate derivatives, 6-chloro-purine-9-carboxylic acid substituted alkyl/arylester 9(a-d, have been synthesized through an intermediate, sodium salt of 6-chloro-9(H-purine (6 which was prepared by the treatment of 6-chloro-9(H-purine (4 with sodium hydride. Structures of the newly synthesized compounds were elucidated by IR, NMR ( 1H and 13C, mass spectra and elemental analysis. Antimicrobial activity against three bacterial strains and three fungal strains at two different concentrations, 100 and 200 µg/mL including MIC values was investigated. Bio-screening data disclosed that most of the sulfonamide derivatives, 7a, 7c and 7d, and one carbamate derivative 9a showed promising antimicrobial activity having MIC values in the range of 18.0-25.0 µg/mL.

  13. VizieR Online Data Catalog: Rotational transitions of Methyl carbamate (Groner+, 2007)

    Science.gov (United States)

    Groner, P.; Winnewisser, M.; Medvedev, I. R.; de, F. C. Lucia; Herbst, E.; Sastry, K. V. L. N.

    2008-11-01

    The rotational-torsional spectrum of the syn conformer of methyl carbamate [CH3OC(:O)NH2], an isomer of the essential amino acid glycine [NH2CH2C(:O)OH], has been recorded at room temperature in the spectral region from 79 to 371GHz. Methyl carbamate possesses a methyl group internal rotor, which gives rise to A and E torsional substates, and associated splittings in the rotational spectrum. Almost 6000 new rotational transitions arising from the vibrational ground state have been assigned, about half of them belonging to the E torsional substate. The Fast Scan Submillimeter-wave Spectroscopic Technique (FASSST) spectrometer at the Ohio State University was used for the present measurements (2 data files).

  14. Highly conductive polymer electrolyte membranes modified with polyethylene glycol-bis-carbamate

    Science.gov (United States)

    Fu, Guopeng; Dempsey, Janel; Kyu, Thein

    By virtue of its non-flammability and chemical stability, polyethylene glycol (PEG) networks have shown potential application in all solid-state polymer electrolyte membranes (PEM). However, room temperature ionic conductivity of these PEG based PEMs is inherently low. Plasticization of these PEMs is needed to improve the ionic conductivity. It was demonstrated by this group that small-molecule plasticizers such as succinonitrile, ethylene carbonate, or urea-carbamate can boost ionic conductivity of solid-state polymer electrolyte membranes. Polyethylene glycol bis-carbamate (PEGBC) was synthesized via condensation reaction of polyethylene glycol diamine and ethylene carbonate. The PEGBC modified PEM has shown higher ionic conductivity relative to the unmodified PEM. Moreover, PEGBC modified PEM has a better thermal stability relative to ethylene carbonate based liquid electrolyte with enhanced ionic conductivity. Supported by NSF-DMR 1161070, 1502543 and REU 1359321.

  15. Optimization of 1,2,5-Thiadiazole Carbamates as Potent and Selective ABHD6 Inhibitors #

    Science.gov (United States)

    Patel, Jayendra Z.; Nevalainen, Tapio J.; Savinainen, Juha R.; Adams, Yahaya; Laitinen, Tuomo; Runyon, Robert S.; Vaara, Miia; Ahenkorah, Stephen; Kaczor, Agnieszka A.; Navia-Paldanius, Dina; Gynther, Mikko; Aaltonen, Niina; Joharapurkar, Amit A.; Jain, Mukul R.; Haka, Abigail S.; Maxfield, Frederick R.; Laitinen, Jarmo T.; Parkkari, Teija

    2015-01-01

    At present, inhibitors of α/β-hydrolase domain 6 (ABHD6) are viewed as a promising approach to treat inflammation and metabolic disorders. This article describes the optimization of 1,2,5-thiadiazole carbamates as ABHD6 inhibitors. Altogether, 34 compounds were synthesized and their inhibitory activity was tested using lysates of HEK293 cells transiently expressing human ABHD6 (hABHD6). Among the compound series, 4-morpholino-1,2,5-thiadiazol-3-yl cyclooctyl(methyl)carbamate (JZP-430, 55) potently and irreversibly inhibited hABHD6 (IC50 44 nM) and showed good selectivity (∼230 fold) over fatty acid amide hydrolase (FAAH) and lysosomal acid lipase (LAL), the main off-targets of related compounds. Additionally, activity-based protein profiling (ABPP) indicated that compound 55 (JZP-430) displayed good selectivity among the serine hydrolases of mouse brain membrane proteome. PMID:25504894

  16. Sensitive and specific multiresidue methods for the determination of pesticides of various classes in clinical and forensic toxicology.

    Science.gov (United States)

    Lacassie, E; Marquet, P; Gaulier, J M; Dreyfuss, M F; Lachâtre, G

    2001-09-15

    Original and sensitive multiresidue methods are presented for the detection and quantitation, in human biological matrices, of 61 pesticides of toxicological significance in human. These methods involved rapid solid-phase extraction using new polymeric support (HLB and MCX) OASIS cartridges. Gas chromatography-mass spectrometry (GC-MS) was used for volatile (organophosphate, organochlorine, phtalimide, uracil) pesticides and liquid chromatography-ionspray-mass spectrometry (LC-MS) for thermolabile and polar pesticides (carbamates, benzimidazoles). Acquisition was performed in the selected ion monitoring (SIM) mode. Extraction recovery varied owing to the nature of pesticides, but was satisfactory for all. Limits of detection (LODs) and limits of quantitation (LOQs) ranged, respectively, from 2.5 to 20 and from 5 to 50ng/ml. An excellent linearity was observed from LOQs up to 1000ng/ml for all the pesticides studied. The proposed procedures yielded reproducible results with good inter-assay accuracy and precision. A few cases of intoxication are presented to demonstrate the diagnostic interest of these methods: in two cases were determined lethal concentrations of endosulfan and carbofuran; in four other cases, the procedures helped diagnose intoxication with, respectively, parathion-ethyl, the association of bromacil and strychnine, bifenthrin and aldicarb. PMID:11516896

  17. A meta-analysis of the effects of pesticides and fertilizers on survival and growth of amphibians.

    Science.gov (United States)

    Baker, Nick J; Bancroft, Betsy A; Garcia, Tiffany S

    2013-04-01

    The input of agrochemicals has contributed to alteration of community composition in managed and associated natural systems, including amphibian biodiversity. Pesticides and fertilizers negatively affect many amphibian species and can cause mortality and sublethal effects, such as reduced growth and increased susceptibility to disease. However, the effect of pesticides and fertilizers varies among amphibian species. We used meta-analytic techniques to quantify the lethal and sublethal effects of pesticides and fertilizers on amphibians in an effort to review the published work to date and produce generalized conclusions. We found that pesticides and fertilizers had a negative effect on survival of -0.9027 and growth of -0.0737 across all reported amphibian species. We also observed differences between chemical classes in their impact on amphibians: inorganic fertilizers, organophosphates, chloropyridinyl, phosphonoglycines, carbamates, and triazines negatively affected amphibian survival, while organophosphates and phosphonoglycines negatively affected amphibian growth. Our results suggest that pesticides and fertilizers are an important stressor for amphibians in agriculturally dominated systems. Furthermore, certain chemical classes are more likely to harm amphibians. Best management practices in agroecosystems should incorporate amphibian species-specific response to agrochemicals as well as life stage dependent susceptibility to best conserve amphibian biodiversity in these landscapes.

  18. New HPLC method to determine ethyl carbamate in alcoholic beverages using fluorescence detection

    OpenAIRE

    Herbert, P; Santos, L.; Bastos, M.; Barros, P.; Alves, A.

    2002-01-01

    A new methodology to the quantification of ethyl carbamate (EC) has been developed. This method allows the analysis by HPLC of ethyl carbarnate in samples of wine, fortified wine, and wine brandy, by a precolumn derivatization with 9-xanthydrol, and fluorescence detection. This does not require previous sample extraction or concentration. The method presents an average recovery of 96% among samples studied, a detection limit of 4.2 mug/L, and an average intermediate precision of 6.3%. The com...

  19. Management of exogenous intoxication by carbamates and organophosphates at an emergency unit

    Directory of Open Access Journals (Sweden)

    Sydney Correia Leão

    2015-10-01

    Full Text Available Summary Objectives: to evaluate and indicate the procedure to be followed in the health unit, both for diagnosis and the treatment of acute exogenous intoxications by carbamates or organophosphates. Methods: a descriptive study based on retrospective analysis of the clinical history of patients diagnosed with intoxication by carbamates or organophosphates admitted at the emergency unit of the Hospital de Urgências de Sergipe Governador João Alves (HUSE between January and December of 2012. Some criteria were evaluated, such as: intoxicating agent; patient's age and gender; place of event, cause, circumstances and severity of the intoxication; as well as signs and symptoms of the muscarinic, nicotinic and neurological effects. Results: seventy patients (average age: 25±19.97 formed the study's population. It was observed that 77.14% of them suffered carbamate intoxication. However, organophosphate intoxications were more severe, with 68.75% of patients presenting moderate to severe forms. Suicide attempt was the leading cause of poisoning, with 62 cases (88.57% of total. Atropine administration was an effective therapeutic approach for treating signs and symptoms, which included sialorrhea (p=0.0006, nausea (p=0. 0029 and emesis (p lt0.0001. The use of activated charcoal was shown effective, both in combating the signs and symptoms presented by both patient groups (p <0.0001. Conclusion: it is concluded that the use of atropine and activated charcoal is highly effective to treat the signs and symptoms developed by patients presenting acute exogenous intoxication by carbamates or organophosphates.

  20. Modeling the vibrational spectrum of 4,4'-diphenylmethane- bis(methyl)carbamate

    Science.gov (United States)

    Shundalau, M. B.; Pitsevich, G. A.; Ksenofontov, M. A.; Umreiko, D. S.

    2010-07-01

    We present results of ab initio calculations of the structure and vibrational IR spectrum for 4,4'-diphenylmethane-bis(methyl)carbamate (DPMC). Calculations were carried out in the HF/6-311G approximation with subsequent force-field scaling. The calculated characteristics of the vibrational spectrum of DPMC show satisfactory agreement with experimental values, which permits them to be used in spectral and structural analysis

  1. Efficient Lewis Acids Catalyzed Aza-Michael Reactions of Enones with Carbamates

    Institute of Scientific and Technical Information of China (English)

    XIA Chun-Gu; XU Li-Wen

    2004-01-01

    The a-amino carbonyl functionality is not only a segment of biologically important natural products but also a versatile intermediate for the synthesis of nitrogen-containing compounds.1 The development of novel synthetic methods leading to a-amino ketone, a-amino acids or their derivatives has attracted much attention in organic synthesis.2 Among the traditional methods for generating a-amino carbonyl compounds, Mannich-type reaction is one of the classical and powerful methods.3 However, the classic Mannich reaction presents serious disadvantages, for example, there is still a drawback in that the silyl enolates have to be prepared from the corresponding carbonyl compounds. Alternatively, aza-Michael additions can be used to create carbon-heteroatom bonds by reaction of a,a-unsaturated carbonyl compounds with amines. Although recent advances have made this route more attractive, development of cheaper, simpler, and more efficient metal catalyst, especially which can be applied to chalcone, is highly desirable.In this paper, we demonstrated that the first aza-Michael reaction of chalcone with a less nucleophilic carbamates can be accomplished on Me3SiCFFeCl3 catalyst system under very mild conditions. Apart from experimental simplicity, the advantages of this methodology are the use of a very cheap Lewis acid catalyst and the insensitivity of the reaction mixture towards air and moisture.catalyst for aza-Michael reaction of chalcone and cyclic enones with carbamates. And with the cyclic enones with carbamates in dichloromethane at room temperature were also investigated. In this conjugate addition reaction, good to excellent yields of a-amino ketones were obtained with system could also mediates aza-Michael addition of carbamates to chalcone and derivatives.These new strategies opened efficient procedures for the synthesis of a-amino ketones under mild conditions.

  2. Deconvolution Method for Determination of the Nitrogen Content in Cellulose Carbamates

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitrogen content for CC can be obtained by using the deconvolution method when the nitrogen content is less than 3.5%. The relationship between the nitrogen content and the absorption intensity ratio of the corresponding separated absorption peaks in FTIR spectra has been expressed by an equation precisely.

  3. Determination of Ethyl Carbamate in Alcoholic Beverages and Fermented Foods Sold in Korea

    OpenAIRE

    Ryu, Dayeon; Choi, Bogyoung; Kim, Eunjoo; Park, Seri; Paeng, Hwijin; Kim, Cho-il; Lee, Jee-yeon; Yoon, Hae Jung; Koh, Eunmi

    2015-01-01

    Ethyl carbamate (EC) classified as a probable human carcinogen (Group 2A) is naturally formed in alcoholic beverages and fermented foods during fermentation process and/or during storage. The objective of this study was to analyze EC in 34 food items including 14 alcoholic beverages and 20 fermented foods sold in Korea. Each food was collected from 18 supermarkets in 9 metropolitan cities in Korea, and then made into composite. According to food composition and alcohol content, samples were d...

  4. Oxime carbamate--discovery of a series of novel FAAH inhibitors.

    Science.gov (United States)

    Sit, S Y; Conway, Charles M; Xie, Kai; Bertekap, Robert; Bourin, Clotilde; Burris, Kevin D

    2010-02-01

    A series of novel oxime carbamates have been identified as potent inhibitors of the key regulatory enzyme of the endocannabinoid signaling system, fatty acid amide hydrolase (FAAH). In this Letter, the rationale behind the discovery and the biological evaluations of this novel class of FAAH inhibitors are presented. Both in vitro and in vivo results of selected targets are discussed, along with inhibition kinetics and molecular modeling studies.(1).

  5. Preparation of sintered silver nanosheets by coating technique using silver carbamate complex

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hee-Yong; Cha, Jae-Ryung; Gong, Myoung-Seon, E-mail: msgong@dankook.ac.kr

    2015-03-01

    This study describes a coating technique approach for large-scale preparation of sintered silver nanosheets whose lateral dimensions were controlled in the thickness range of 50–65 nm. These procedures involved coating water-soluble poly (vinyl alcohol) (PVA) and silver 2-ethylhexylcarbamate (Ag-EHC), as well as thermal reduction of a silver precursor by heating at 150 °C, followed by dissolving away the PVA layer with alcoholic water. When the silver carbamate layer on the PVA layer was heated to 150 °C, the silver carbamate layer was thermally reduced and directed to grow into uniform sintered nanosheets with aspect ratios as high as 1000. The multi-stacked PVA/Ag structures and sintered silver nanosheets were confirmed by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Measurements of the conductive property at room temperature indicated that these nanosheets were electrically continuous with a resistivity of approximately 7.3 × 10{sup −6} Ω cm. - Highlights: • A coating technique is used to make sintered Ag nanosheets. • PVA and silver carbamate act as a separation layer and a silver precursor. • The Ag nanosheets have thickness width 50–60 nm and width up to hundred μm. • The Ag nanosheets showed a resistivity of ca. 7.3 × 10{sup −6} Ω cm.

  6. Novel cinchona carbamate selectors with complementary enantioseparation characteristics for N-acylated amino acids.

    Science.gov (United States)

    Krawinkler, Karl Heinz; Maier, Norbert M; Ungaro, Rocco; Sansone, Francesco; Casnati, Alessandro; Lindner, Wolfgang

    2003-01-01

    The synthesis and chromatographic evaluation of the enantiomer separation capabilities of covalently immobilized calix[4]arene-cinchona carbamate hybrid type receptors derived from quinine (QN) and its corresponding C9-epimer (eQN) in different solvents are reported. The receptors display complementary enantiomer separation profiles in terms of elution order, chiral substrate specificity, and mobile phase characteristics, indicating the existence of two distinct chiral recognition mechanisms. The QN-derived receptor binds the (S)-enantiomers of N-acylated amino acids more strongly, shows preferential recognition of open-chained amino acids, and superior enantioselectivity in polar media such as methanol/acetic acid. In contrast, the eQN congener preferentially recognizes the corresponding (R)-enantiomers, displays good enantioselectivity (alpha up to 1.74) for cyclic amino acids, and enhanced stereodiscriminating properties in apolar mobile phases, e.g., chloroform/acetic acid. A comparison of the enantiomer separation profiles with those of the corresponding QN and eQN tert-butyl carbamate congeners indicates no significant level of cooperativity between the calix[4]arene module and the cinchona units in terms of overall chiral recognition, most probably as a consequence of residual conformational flexibility of the calixarene module and the carbamate linkage.

  7. Evaluation System for Pesticides (ESPE). 1. Agricultural pesticides

    OpenAIRE

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of Substances (USES). The evaluation system for pesticides (ESPE) is divided in three parts: 1) emission of the pesticide ; 2) distribution over and within the different environmental compartments and c...

  8. Pesticide Movement in Response to Furrow Irrigation and Pesticide Parameters

    OpenAIRE

    Peralta, Richard C.; Hill, Robert W.; Deer, Howard

    1991-01-01

    Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses from insects, pathogens, weeds and other pests. The term pesticide refers to a large number ofchemical compounds. Pesticides include acaricides, fungicides, herbicides, insecticides, nematicides, algicides, arboricides, zoocides, and many more.

  9. Decontaminating pesticide protective clothing.

    Science.gov (United States)

    Laughlin, J

    1993-01-01

    The review of recent work on the mechanisms of soil removal from textiles assists in understanding decontamination of pesticide protective clothing. The current work provides explanatory conclusions about residue retention as a basis of making recommendations for the most effective decontamination procedures. A caution about generalizations: Some pesticides produce very idiosyncratic responses to decontamination. An example is the paraquat/salt response. Other pesticides exhibit noticeable and unique responses to a highly alkaline medium (carbaryl), or to bleach (chlorpyrifos), or are quickly volatilized (methyl parathion). Responses such as these do not apply to other pesticides undergoing decontamination. Given this caution, there are soil, substrate, and solvent responses that do maximize residue removal. Residue removal is less complete as the concentration of pesticide increases. The concentration of pesticide in fabric builds with successive exposures, and the more concentrated the pesticide, the more difficult the removal. Use a prewash product and/or presoak. The surfactant and/or solvent in a prewash product is a booster in residue removal. Residues transfer from contaminated clothing to other clothing during the washing cycle. Use a full washer of water for a limited number of garments to increase residue removal. The hotter the washing temperature, the better. Generally, this means a water temperature of at least 49 degrees C, and preferably 60 degrees C. Select the detergent shown to be more effective for the formulation: heavy-duty liquid detergents for emulsifiable concentrate formulations and powdered phosphate detergents for wettable powder formulations. If the fabric has a soil-repellent finish, use 1.25 times the amount recommended on the detergent label. For water hardness above 300 ppm, an additional amount of powdered phosphate detergent is needed to obtain the same level of residue removal as obtained with the heavy-duty liquid detergent when

  10. Human Health Benchmarks for Pesticides

    Data.gov (United States)

    U.S. Environmental Protection Agency — Advanced testing methods now allow pesticides to be detected in water at very low levels. These small amounts of pesticides detected in drinking water or source...

  11. Pesticides and earthworms. A review

    OpenAIRE

    Pelosi, Céline; Barot, Sebastien; Capowiez, Yvan; Hedde, Mickaël; Vandenbulcke, Franck

    2014-01-01

    International audience Earthworms provide key soil functions that favour many positive ecosystem services. These services are important for agroecosystem sustainability but can be degraded by intensive cultural practices such as use of pesticides. Many literature reports have investigated the effect of pesticides on earthworms. Here, we review those reports to assess the relevance of the indicators of earthworm response to pesticides, to assess their sensitivity to pesticides, and to highl...

  12. 19F nuclear magnetic resonance analysis of the carbamate reaction of alpha-fluoro-beta-alanine (FBAL), the major catabolite of fluoropyrimidines. Application to FBAL carbamate determination in body fluids of patients treated with 5'-deoxy-5-fluorouridine

    International Nuclear Information System (INIS)

    alpha-Fluoro-beta-alanine (FBAL), the major catabolite of the antineoplastic fluoropyrimidines, is an amino acid which is in equilibrium with its carbamate derivative in weakly alkaline aqueous solutions containing carbonate. In both water and control biological fluids (urine, plasma) spiked with FBAL (and sodium bicarbonate, in some cases), 19F NMR was used: (i) to determine the pH range over which FBAL carbamate is present (pH greater than or equal to 7), the maximum concentration formed occurring around pH 9, (ii) to show that the amino group of FBAL interacts very slowly with a non-protein plasma component to form a compound X, unstable in acid medium. The presumed structure of X is RCONHCH2CHFCOOH, with R different from an alkyl group but still unidentified. The behavior of FBAL in urine and plasma of rats treated with FBAL or 5'-deoxy-5-fluorouridine (5'-dFUrd), a prodrug of 5-fluorouracil, and from patients treated with 5'-dFUrd was investigated. FBAL carbamate was not present in acid medium and was therefore absent in acidic human urine. However, it was found in alkaline rat urine. FBAL carbamate was found in plasma along with the compound X. The 19F NMR spectra of FBAL and derivatives are complex since alpha-fluoro-beta-ureido-propionic acid, the precursor of FBAL in the catabolic pathway of antineoplastic fluoropyrimidines, produces a signal overlapping that of FBAL carbamate, and very close to that of compound X

  13. Shanghai Pesticide Research Institute (SPRI)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Shanghai Pesticide Research Institute (SPRI), established in 1963, is the first professional pesticide institute in China. After being approved by the Science & Technology Committee of PRC, it became the base for Shanghai Branch of National Pesticide R&D South center.

  14. Case study to illustrate an approach for detecting contamination and impurities in pesticide formulations.

    Science.gov (United States)

    Karasali, Helen; Kasiotis, Konstantinos M; Machera, Kyriaki; Ambrus, Arpad

    2014-11-26

    Counterfeit pesticides threaten public health, food trade, and the environment. The present work draws attention to the importance of regular monitoring of impurities in formulated pesticide products. General screening revealed the presence of carbaryl as a contaminant in a copper oxychloride formulated product. In this paper, as a case study, a liquid chromatographic diode array-mass spectrometric method developed for general screening of pesticide products and quantitative determination of carbaryl together with its validation is presented. The proposed testing strategy is considered suitable for use as a general approach for testing organic contaminants and impurities in solid pesticide formulations. PMID:25360991

  15. Case study to illustrate an approach for detecting contamination and impurities in pesticide formulations.

    Science.gov (United States)

    Karasali, Helen; Kasiotis, Konstantinos M; Machera, Kyriaki; Ambrus, Arpad

    2014-11-26

    Counterfeit pesticides threaten public health, food trade, and the environment. The present work draws attention to the importance of regular monitoring of impurities in formulated pesticide products. General screening revealed the presence of carbaryl as a contaminant in a copper oxychloride formulated product. In this paper, as a case study, a liquid chromatographic diode array-mass spectrometric method developed for general screening of pesticide products and quantitative determination of carbaryl together with its validation is presented. The proposed testing strategy is considered suitable for use as a general approach for testing organic contaminants and impurities in solid pesticide formulations.

  16. Control of Pesticides 2004

    DEFF Research Database (Denmark)

    Krongaard, T.; Petersen, K. K.; Christoffersen, C.

    Four different groups of products covered by the pesticide regulation were included in the 2004 analytical chemical authority control: 1) Herbicides containing bentazone, dicamba, dichlorprop-P, mecoprop-P, MCPA, foramsulfuron, iodosulfuron-methylsodium, rimsulfuron and triasulfuron. 2) Fungicides...... coumatetralyl and one out of four contained dicamba complied with the accepted tolerance limits with respect to the content of the active ingredient as specified in Danish Statutory Order on pesticides. None of the examined samples contained OPEO, but one of the samples contained NPEO. On three products...

  17. Exposure to pesticides and metal contaminants of fertilizer among tree planters.

    Science.gov (United States)

    Gorman Ng, Melanie; Stjernberg, Ernst; Koehoorn, Mieke; Demers, Paul A; Davies, Hugh W

    2011-08-01

    In British Columbia, Canada, harvested forests are manually replanted by seasonal workers. The work is known to be physically demanding and ergonomically difficult, and recently, there have been concerns over chemical exposures due to pesticide residues on seedlings, fertilizers (often applied alongside seedlings), and potential metal contamination of these fertilizers. This study aimed to characterize metal and pesticide exposure among a sample of British Columbia tree planters. Between May 2006 and April 2007, exposure measurements were taken from 54 tree planters at five geographically disperse worksites throughout British Columbia. Four worksites were using fertilizer and one was not. Metal concentrations were measured by inductively coupled plasma mass spectrometry on post-shift hand wipes, full-shift personal air sample, bulk soil, seedling root balls, and fertilizer samples. Pesticides were measured on post-shift hand wipes and on bulk seedling samples. Seedling nursery pesticide application records were used to focus pesticide analyses on pesticides known to have been applied to the seedlings used at the study sites. Carbamate pesticides were analyzed by high-performance liquid chromatography/mass spectroscopy and all other pesticides by gas chromatography mass spectrometry. No evidence was found that tree planters who worked with fertilizer were at an elevated risk of exposure to arsenic, lead, cadmium, chromium, and nickel relative to tree planters who did not. Pesticide residues were found on seedlings taken from work sites early in the tree planting season in April 2007. At these worksites, the fungicides chlorothalonil and iprodione were found on the skin of workers at low levels (range 0.37-106.3 ng cm(-2) and 0.48-15.9 ng cm(-2), respectively), providing evidence for exposure potential. Very poor hygiene conditions were observed at all tree planting work sites. Hand washing facilities were not available at work sites and only 5.6% of subjects

  18. Statistical Analysis of Regularity of Pesticide Residues in Vegetables Produced in Inner Mongoli

    Institute of Scientific and Technical Information of China (English)

    Fujin ZHANG; Dekun HOU; Jiang HE; Tianyun GAO; Hong LUO; Songyan LANG; Xinxin ZHANG; Yiping YAO

    2013-01-01

    [Objective] The paper was to study regularity of pesticide residues in veg-etables produced in Inner Mongolia. [Method] Mathematical statistic analysis was carried out on 6 800 samples of veggies, fruits, leguminous vegetables, nuts and seeds produced in Inner Mongolia. [Result] The dominated vegetables in Inner Mon-golia were green leafy vegetables, solanaceous vegetables and melon vegetables, and their yields accounted for 70% of the total vegetables production. Since 2003, with the rapid increase of detected vegetable numbers, the status of vegetable qual-ity safety had entered into a new stage of sustainable steady after a rapid decline or periodic fluctuation, and the differences in safety levels were obvious, of which the range of exceeding standard rate of pesticide residues in solanaceous vegeta-bles, melon vegetables and leguminous vegetables (about 55% of the total vegeta-bles) was under 2%, with average values of 1.1%, 1.6% and 3.1%, respectively. They belonged to stable type. The exceeding standard rate of pesticide residues in green leafy vegetables and Chinese cabbage group (about 30% of total vegetables) presented a decreasing trend year by year, wondering in the range of 7%-10%. They belonged to main risk type. The time period of exceeding standard of pesticide residues in root vegetables and cole vegetables was under predictable, and its ex-ceeding standard rate in some years was over 5% (amplitude variation is over 15 percentage points). They belonged to random risk type. The kinds of pesticides, which exceeding standard rate in vegetables were relatively intensive, presented vari-ance in different vegetable species. 70% of the pesticides belonged to intermittent over-limits and the probability was below 5%. About 20% tradition pesticides often exceeded standard and their probabilities were over 30%. The exceeding standard of organophosphorus and carbamates pesticides in vegetables presented a decreasing tend, while the risk of some new pesticides

  19. Discovery of Highly Selective and Nanomolar Carbamate-Based Butyrylcholinesterase Inhibitors by Rational Investigation into Their Inhibition Mode.

    Science.gov (United States)

    Sawatzky, Edgar; Wehle, Sarah; Kling, Beata; Wendrich, Jan; Bringmann, Gerhard; Sotriffer, Christoph A; Heilmann, Jörg; Decker, Michael

    2016-03-10

    Butyrylcholinesterase (BChE) is a promising target for the treatment of later stage cognitive decline in Alzheimer's disease. A set of pseudo-irreversible BChE inhibitors with high selectivity over hAChE was synthesized based on carbamates attached to tetrahydroquinazoline scaffolds with the 2-thiophenyl compound 2p as the most potent inhibitor of eqBChE (KC = 14.3 nM) and also of hBChE (KC = 19.7 nM). The inhibitors transfer the carbamate moiety onto the active site under release of the phenolic tetrahydroquinazoline scaffolds that themselves act as neuroprotectants. By combination of kinetic data with molecular docking studies, a plausible binding model was probed describing how the tetrahydroquinazoline scaffold guides the carbamate into a close position to the active site. The model explains the influence of the carrier scaffold onto the affinity of an inhibitor just before carbamate transfer. This strategy can be used to utilize the binding mode of other carbamate-based inhibitors.

  20. On the paradox of pesticides

    OpenAIRE

    Li, Y. Charles; Yang, Yipeng

    2013-01-01

    The paradox of pesticides was observed experimentally, which says that pesticides may dramatically increase the population of a pest when the pest has a natural predator. Here we use a mathematical model to study the paradox. We find that the timing for the application of pesticides is crucial for the resurgence or non-resurgence of the pests. In particular, regularly applying pesticides is not a good idea as also observed in experiments. In fact, the best time to apply pesticides is when the...

  1. Comparative study of human and mouse pregnane X receptor agonistic activity in 200 pesticides using in vitro reporter gene assays

    International Nuclear Information System (INIS)

    The nuclear receptor, pregnane X receptor (PXR), is a ligand-dependent transcription factor that regulates genes involved in xenobiotic metabolism. Recent studies have shown that PXR activation may affect energy metabolism as well as the endocrine and immune systems. In this study, we characterized and compared the agonistic activities of a variety of pesticides against human PXR (hPXR) and mouse PXR (mPXR). We tested the hPXR and mPXR agonistic activity of 200 pesticides (29 organochlorines, 11 diphenyl ethers, 56 organophosphorus pesticides, 12 pyrethroids, 22 carbamates, 12 acid amides, 7 triazines, 7 ureas, and 44 others) by reporter gene assays using COS-7 simian kidney cells. Of the 200 pesticides tested, 106 and 93 activated hPXR and mPXR, respectively, and a total of 111 had hPXR and/or mPXR agonistic activity with greater or lesser inter-species differences. Although all of the pyrethroids and most of the organochlorines and acid amides acted as PXR agonists, a wide range of pesticides with diverse structures also showed hPXR and/or mPXR agonistic activity. Among the 200 pesticides, pyributicarb, pretilachlor, piperophos and butamifos for hPXR, and phosalone, prochloraz, pendimethalin, and butamifos for mPXR, acted as particularly potent activators at low concentrations in the order of 10-8-10-7 M. In addition, we found that several organophosphorus oxon- and pyributicarb oxon-metabolites decreased PXR activation potency compared to their parent compounds. These results suggest that a large number of structurally diverse pesticides and their metabolites possess PXR-mediated transcriptional activity, and their ability to do so varies in a species-dependent manner in humans and mice.

  2. Temperature-dependent acute toxicity of methomyl pesticide on larvae of 3 Asian amphibian species.

    Science.gov (United States)

    Lau, Edward Tak Chuen; Karraker, Nancy Elizabeth; Leung, Kenneth Mei Yee

    2015-10-01

    Relative to other animal taxa, ecotoxicological studies on amphibians are scarce, even though amphibians are experiencing global declines and pollution has been identified as an important threat. Agricultural lands provide important habitats for many amphibians, but often these lands are contaminated with pesticides. The authors determined the acute toxicity, in terms of 96-h median lethal concentrations, of the carbamate pesticide methomyl on larvae of 3 Asian amphibian species, the Asian common toad (Duttaphrynus melanostictus), the brown tree frog (Polypedates megacephalus), and the marbled pygmy frog (Microhyla pulchra), at 5 different temperatures (15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) to examine the relationships between temperature and toxicity. Significant interspecific variation in methomyl sensitivity and 2 distinct patterns of temperature-dependent toxicity were found. Because high proportions of malformation among the surviving tadpoles were observed, a further test was carried out on the tree frog to determine effect concentrations using malformation as the endpoint. Concentrations as low as 1.4% of the corresponding 96-h median lethal concentrations at 25 °C were sufficient to cause malformation in 50% of the test population. As the toxicity of pesticides may be significantly amplified at higher temperatures, temperature effects should not be overlooked in ecotoxicological studies and derivation of safety limits in environmental risk assessment and management.

  3. Temperature-dependent acute toxicity of methomyl pesticide on larvae of 3 Asian amphibian species.

    Science.gov (United States)

    Lau, Edward Tak Chuen; Karraker, Nancy Elizabeth; Leung, Kenneth Mei Yee

    2015-10-01

    Relative to other animal taxa, ecotoxicological studies on amphibians are scarce, even though amphibians are experiencing global declines and pollution has been identified as an important threat. Agricultural lands provide important habitats for many amphibians, but often these lands are contaminated with pesticides. The authors determined the acute toxicity, in terms of 96-h median lethal concentrations, of the carbamate pesticide methomyl on larvae of 3 Asian amphibian species, the Asian common toad (Duttaphrynus melanostictus), the brown tree frog (Polypedates megacephalus), and the marbled pygmy frog (Microhyla pulchra), at 5 different temperatures (15 °C, 20 °C, 25 °C, 30 °C, and 35 °C) to examine the relationships between temperature and toxicity. Significant interspecific variation in methomyl sensitivity and 2 distinct patterns of temperature-dependent toxicity were found. Because high proportions of malformation among the surviving tadpoles were observed, a further test was carried out on the tree frog to determine effect concentrations using malformation as the endpoint. Concentrations as low as 1.4% of the corresponding 96-h median lethal concentrations at 25 °C were sufficient to cause malformation in 50% of the test population. As the toxicity of pesticides may be significantly amplified at higher temperatures, temperature effects should not be overlooked in ecotoxicological studies and derivation of safety limits in environmental risk assessment and management. PMID:25959379

  4. Kombinationseffekter af pesticider

    DEFF Research Database (Denmark)

    Kudsk, Per; Andersen, Helle Raun; Cedergreen, Nina;

    Resumé: Effekten af 101 tokomponentblandinger og 20 trekomponentblandinger bestående af 22 forskellige pesticider blev undersøgt i 7 forskellige testsystemer. Effekterne af blandingerne blev sammenholdt med pesticidernes virkningsmekanismer/virkemåder med henblik på at undersøge, om det med...

  5. Knowledge, Attitudes, Practices and Biomonitoring of Farmers and Residents Exposed to Pesticides in Brazil

    Directory of Open Access Journals (Sweden)

    Eloisa Dutra Caldas

    2012-08-01

    Full Text Available In this study, the knowledge, attitudes and practices regarding pesticide use and the levels of exposure of farmers and residents to organophosphorous and/or carbamates pesticides were evaluated in two rural settings in Brazil. A questionnaire was completed by 112 farm workers aged ≥18 years. Almost all farmers acknowledged that pesticides were potentially harmful to their health (87.5%; however, over half rarely (48.2% or never (7.2% used personal protective devices (PPDs. An association was found (p = 0.001 between the work regimen and the use of PPDs, with more frequent equipment use among hired laborers than those involved in family agriculture. A significant correlation (p = 0.027 was found between the reporting of adverse symptoms and the use of backpack sprayers. Mean AChE activities of farmers (n = 64 and residents (n = 18 during the exposure and non-exposure periods were significantly lower than their control groups. Mean BChE activities of farmers and residents were significantly lower than their controls during the exposure period. Among the 60 farmers that had blood samples collected in both the exposure and non-exposure (baseline periods, 10 (16.7% had AChE depletion of over 30% during the exposure period compared with the baseline level. Six residents living on the same farms also presented this depletion. AChE was over 30% higher than the baseline level for 19 farmers (31.7%, indicating a reboot effect. Special education programs are needed in these regions to promote the safe use of pesticides in the field to decrease the risks from exposure to pesticides for farmers, and from secondary exposure to these compounds for their families.

  6. Environmental impact of pesticides after sewage treatment plants removal in four Spanish Mediterranean rivers

    Science.gov (United States)

    Campo, Julian; Masiá, Ana; Blasco, Cristina; Picó, Yolanda; Andreu, Vicente

    2013-04-01

    The re-use of sewage treatment plant (STP) effluents is currently one of the most employed strategies in several countries to deal with the water shortage problem. Some pesticides are bio-accumulative and due to their toxicity they can affect non-target organisms, especially in the aquatic ecosystems, threating their ecological status. Despite these facts, and to our knowledge, there are few peer-reviewed articles that report concentrations of pesticides in Spanish STPs. This work presents the results of an extensive survey that was carried out in October of 2010 in 15 of the STPs of Ebro, Guadalquivir, Jucar and Llobregat rivers in Spain. Forty-three currently used pesticides, belonging to anilide, neonicotinoid, thiocarbamate, acaricide, juvenile hormone mimic, insect growth regulator, urea, azole, carbamate, chloroacetanilide, triazine and organophosphorus, have been monitored. Integrated samples of influent and effluent, and dehydrated, lyophilized sludge from 15 STPs located along the rivers were analyzed for pesticide residues. With these data, removal efficiencies are also calculated. Extraction of water samples was performed through Solid Phase Extraction (SPE) and sludge samples were extracted using the QuEchERS method. Pesticide determination was carried out using Liquid Chromatograph - tandem Mass Spectrometry (LC-MS/MS). Recoveries ranged from 48% to 70%, in water samples, and from 40 to 105 %, in sludge samples. The limits of quantification were 0.01-5 ng L-1 for the former, and 0.1-5.0 ng g-1 for the latter. In terms of frequency of detection, 31 analytes were detected in influent, 29 in effluent and 11 in sludge samples. Organophosphorus pesticides were the most frequently detected in all wastewater samples, but azole, urea, triazine, neonicotinoid and the insect growth regulator were also commonly found. Imazalil revealed the maximum concentration in wastewater samples from all rivers except the Guadalquivir, in which diuron presented the maximum

  7. Combating highly resistant emerging pathogen Mycobacterium abscessus and Mycobacterium tuberculosis with novel salicylanilide esters and carbamates.

    Science.gov (United States)

    Baranyai, Zsuzsa; Krátký, Martin; Vinšová, Jarmila; Szabó, Nóra; Senoner, Zsuzsanna; Horváti, Kata; Stolaříková, Jiřina; Dávid, Sándor; Bősze, Szilvia

    2015-08-28

    In the Mycobacterium genus over one hundred species are already described and new ones are periodically reported. Species that form colonies in a week are classified as rapid growers, those requiring longer periods (up to three months) are the mostly pathogenic slow growers. More recently, new emerging species have been identified to lengthen the list, all rapid growers. Of these, Mycobacterium abscessus is also an intracellular pathogen and it is the most chemotherapy-resistant rapid-growing mycobacterium. In addition, the cases of multidrug-resistant Mycobacterium tuberculosis infection are also increasing. Therefore there is an urgent need to find new active molecules against these threatening strains. Based on previous results, a series of salicylanilides, salicylanilide 5-chloropyrazinoates and carbamates was designed, synthesized and characterised. The compounds were evaluated for their in vitro activity on M. abscessus, susceptible M. tuberculosis H37Rv, multidrug-resistant (MDR) M. tuberculosis MDR A8, M. tuberculosis MDR 9449/2006 and on the extremely-resistant Praha 131 (XDR) strains. All derivatives exhibited a significant activity with minimum inhibitory concentrations (MICs) in the low micromolar range. Eight salicylanilide carbamates and two salicylanilide esters exhibited an excellent in vitro activity on M. abscessus with MICs from 0.2 to 2.1 μM, thus being more effective than ciprofloxacin and gentamicin. This finding is potentially promising, particularly, as M. abscessus is a threateningly chemotherapy-resistant species. M. tuberculosis H37Rv was inhibited with MICs from 0.2 μM, and eleven compounds have lower MICs than isoniazid. Salicylanilide esters and carbamates were found that they were effective also on MDR and XDR M. tuberculosis strains with MICs ≥1.0 μM. The in vitro cytotoxicity (IC50) was also determined on human MonoMac-6 cells, and selectivity index (SI) of the compounds was established. In general, salicylanilide

  8. Synthesis of dimethyl carbonate from methyl carbamate and methanol using a Fixed-Bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D. [Zaozhuang University, College of Chemistry, Chemical Engineering and Materials Science, Zaozhuang (China); Zhang, X. [Zaozhuang University, College of Chemistry, Chemical Engineering and Materials Science, Zaozhuang (China); Chinese Academy of Sciences, Institute of Coal Chemistry, State Key Laboratory of Coal Conversion, Taiyuan (China); Wei, W.; Sun, Y. [Chinese Academy of Sciences, Institute of Coal Chemistry, State Key Laboratory of Coal Conversion, Taiyuan (China)

    2012-12-15

    Several mixed oxide catalysts were prepared by coprecipitation for dimethyl carbonate (DMC) synthesis from methyl carbamate and methanol. During the batch process, the DMC yield was below 35 %. In order to minimize the unfavorable thermodynamic equilibrium and side reactions for the DMC synthesis, a fixed-bed reactor was designed. A maximum DMC yield of {proportional_to} 73 % could be realized over a ZnO-Al{sub 2}O{sub 3} catalyst. The effects of reaction conditions for this type of reactor were investigated in detail. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. In Situ Blood-Brain Barrier Permeability of a C-10 Paclitaxel Carbamate

    OpenAIRE

    Ballatore, Carlo; Zhang, Bin; Trojanowski, John Q.; Lee, Virginia M.-Y.; Smith, Amos B.

    2008-01-01

    We report the synthesis and blood-brain barrier (BBB) permeability of 14C-CNDR-29, a paclitaxel C-10 carbamate derivative shown to be devoid of P-glycoprotein (Pgp)-interactions, in an in situ mouse brain perfusion model, in comparison with 14C-paclitaxel. The results presented reveal a 3–4 fold higher BBB-permeability for the C-10 modified taxane compared to paclitaxel. These results support the notion that circumvention of Pgp-mediated efflux can lead to higher BBB-permeability. Further stu...

  10. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

    OpenAIRE

    Li-Si Huang; Fei He; Hui Huang; Xiao-Yong Zhang; Shu-Hua Qi

    2012-01-01

    Five carbamate derivatives, obtucarbamates C and D (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (−)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (−)-4α,10β-aromadendranediol (8), (+)-4β,10β-aromadendrane...

  11. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

    OpenAIRE

    Huang, Li-Si; He, Fei; Huang, Hui; Zhang, Xiao-yong; Qi, Shu-Hua

    2012-01-01

    Five carbamate derivatives, obtucarbamates C and D (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (−)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (−)-4α,10β-aromadendranediol (8), (+)-4β,10β-aromadendranediol (9) were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. ...

  12. Equilibrium constant for carbamate formation from monoethanolamine and its relationship with temperature

    Energy Technology Data Exchange (ETDEWEB)

    Aroua, M.K.; Benamor, A.; Haji-Sulaiman, M.Z. [Univ. of Malaya, Kuala Lumpur (Malaysia). Dept. of Chemical Engineering

    1999-09-01

    Removal of acid gases such as CO{sub 2} and H{sub 2}S using aqueous solutions of alkanolamines is an industrially important process. The equilibrium constant for the formation of carbamate from monoethanolamine was evaluated at various temperatures of 298, 308, 318, and 328 K and ionic strengths up to 1.7 M. From the plot of log{sub 10} K versus I{sup 0.5}, the variation of the thermodynamical constant with temperature follows the relationship log{sub 10} K{sub 1} = {minus}0.934 + (0.671 {times} 10{sup 3})K/T.

  13. The role of kaolin particles in the performance of a carbamate-based biocide for water bacterial control

    OpenAIRE

    Maria Olivia Pereira; Maria João Vieira; Melo, Luis F.

    2002-01-01

    The influence of kaolin particles on the activity of Pseudomonas fuorescens and on the efficacy of a carbamate-based biocide was investigated. The results indicated that kaolin particles stimulated the activity of the bacteria for all buffered pH values studied (5, 7, and 9); this effect being more evident for the tests carried out at pH 5 and 9. The presence of the clay in P. fuorescens suspensions decreased the efficiency of disinfection of the carbamate. The results also showed that kaolin...

  14. Genotoxicity of Pesticide Waste Contaminated Soil and Its Leachate

    Institute of Scientific and Technical Information of China (English)

    S. D. SIVANESAN; K. KRISHNAMURTHI; S. D. WACHASUNDER; T. CHAKRABARTI

    2004-01-01

    Improper land disposal of hazardous waste can result in leaching of hazardous constituents which may contaminate ground and surface water leading to adverse impact on human health and environment consequences. The present study utilized mammalian cell culture for the genotoxicity assessment of waste and its leachate. Methods Genotoxic potential and chemical analysis of pesticide derived tarry waste contaminated soil extract and its leachate was assessed using in vitro human lymphocyte cultures and GC-MS. Results The investigation revealed that the soil extract could cause significant to highly significant genotoxicity in the form of DNA strand break at 25 μL (P<0.01), 50 μL, 100 μL and 200 μL (P<0.001) and chromosomal aberration at 25 μL (P<0.01) and 50 μL and 100 μL (P<0.001). The leachate could cause significant DNA strand break and chromosomal aberration only at 100 μL and 200 μL (P<0.01) dose levels. Conclusion The genotoxicity observed is attributed to carbaril and tetra methyl naphthyl carbamate, the major ingredients of the extracts, as revealed by GC-MS.

  15. Reusable fiber optic immunofluorosensor for rapid detection of pesticides

    Science.gov (United States)

    Anis, Nabil A.; Valdes, James J.; Thompson, Roy G.; Menking, Darrell E.; Wong, Rosie B.; Eldefrawi, Mohyee E.

    1993-05-01

    Quartz fibers coated with acetylcholinesterase (AChE) or antibody (Ab) are used as biosensors utilizing total reflectance fluorescence for the rapid detection of pesticides. The enzyme biosensor was constructed by immobilizing fluorescein isothiocyanate (FITC)-tagged eel electric organ AChE on quartz fibers. The fluorescent signal was generated by hydrolysis of acetylcholine (ACh) that is present in the perfusate. Organophosphate (OP) and carbamate anticholinesterase (AntiChE) insecticides inhibited AChE and reduced the fluorescent quenching resulting from AChE hydrolysis. A parathion biosensor was constructed by immobilizing casein-parathion on the quartz fibers, that bound rabbit antiparathion antibody. The optical signal was generated by perfusing the fibers with fluorescein-labeled goat antirabbit IgG. Free parathion inhibited the binding of antiparathion Abs and reduced the optical signal and provided the basis for detection of parathion. Another immunosensor developed detected the herbicide PursuitR by utilizing the reversible binding of a fluorescein-Pursuit derivative to antiPursuit Abs immobilized on the fiber. Unlabeled Pursuit competed effectively and displaced the bound fluorescent compound in a dose-dependent manner. The sensor discriminated effectively between Pursuit-like and structurally unrelated herbicides. The immunosensor offers the advantage of continuous monitoring, ease of operation, speed of detection, low cost, stability, specificity, matrix transparency, and reusability.

  16. A novel optimised and validated method for analysis of multi-residues of pesticides in fruits and vegetables by microwave-assisted extraction (MAE)-dispersive solid-phase extraction (d-SPE)-retention time locked (RTL)-gas chromatography-mass spectrometry with Deconvolution reporting software (DRS).

    Science.gov (United States)

    Satpathy, Gouri; Tyagi, Yogesh Kumar; Gupta, Rajinder Kumar

    2011-08-01

    A rapid, effective and ecofriendly method for sensitive screening and quantification of 72 pesticides residue in fruits and vegetables, by microwave-assisted extraction (MAE) followed by dispersive solid-phase extraction (d-SPE), retention time locked (RTL) capillary gas-chromatographic separation in trace ion mode mass spectrometric determination has been validated as per ISO/IEC: 17025:2005. Identification and reporting with total and extracted ion chromatograms were facilitated to a great extent by Deconvolution reporting software (DRS). For all compounds LOD were 0.002-0.02mg/kg and LOQ were 0.025-0.100mg/kg. Correlation coefficients of the calibration curves in the range of 0.025-0.50mg/kg were >0.993. To validate matrix effects repeatability, reproducibility, recovery and overall uncertainty were calculated for the 35 matrices at 0.025, 0.050 and 0.100mg/kg. Recovery ranged between 72% and 114% with RSD of <20% for repeatability and intermediate precision. The reproducibility of the method was evaluated by an inter laboratory participation and Z score obtained within ±2. PMID:25214130

  17. Development and validation of method for the determination of organochlorine pesticides and trihalomethanes in the water by HRGC-ECD = Desenvolvimento e validação de método para a determinação de pesticidas organoclorados e trihalometanos em água usando HRGC-ECD

    Directory of Open Access Journals (Sweden)

    Maria Isabel Ribeiro Alves

    2010-10-01

    Full Text Available The development and validation of a simultaneous liquid-liquid extraction method for organochlorine pesticides and trihalomethanes in surface and drinking water by HRGC-ECD is described. The method presents acceptable recovery, with detection ranging from 2.7 to 49.0 ng L-1 for organochlorine pesticides and from 18.0 to 860.0 ng L-1for trihalomethanes. The extraction method also presents excellent linearity for all the analytes, with excellent repeatability. Extraction is simple, fast, and low cost, uses small amounts of solvent and aqueous sample, and is suitable for routine analyses.O presente trabalho trata do desenvolvimento e validação de um método de extração para a determinação simultânea de trihalometanos e pesticidas organoclorados em água superficial e água potável por HRGC-ECD. O método apresenta recuperação aceitável, com limites dedetecção que variam de 2,7 a 49,0 ng L-1 para pesticidas organoclorados e de 18,0 a 860,0 ng L-1 para trihalometanos. O método de extração apresenta também excelente linearidade para todos os analitos e boa repetibilidade. A extração é simples, rápida, de baixo custo, além de utilizar pequenas quantidades de solvente e de amostra aquosa, sendo, portanto, de alta aplicabilidade em análises de rotina.

  18. Radiation induced microbial pesticide

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Young Keun; Kim, Jae Sung; Kim, Jin Kyu; Lee, Sang Jae

    2000-01-01

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  19. Radiation induced microbial pesticide

    International Nuclear Information System (INIS)

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  20. Pesticides in Uruguay.

    Science.gov (United States)

    Mañay, N; Rampoldi, O; Alvarez, C; Piastra, C; Heller, T; Viapiana, P; Korbut, S

    2004-01-01

    This is a review, from an independent and scientific point of view, of the different aspects involved in the issue of pesticides in Uruguay. In its preparation, the University, responsible official institutions, nongovenment environmental organizations, and independent experts have been consulted. As to the legal framework, the responsibilities of the institutions are described and evaluated. The earlier and current regulations for the registration and sale of pesticides are presented, as well as the available information on the active ingredients most used in Uruguay. Official control is evaluated in reference to pesticide residues in food, drinking water, and the environment and to final waste disposal. Maximum allowed residue limits and the responsibilities of the corresponding governmental institutions are presented. Emphasis is placed on the fact that there are no publicly available data. Several research programs are presented, mainly from academia, and usually are not completed due to lack of financial support. In the conclusions the most problematic aspects are pointed out, emphasizing the need to improve national regulations for the country to establish an effective system of control. The importance of financial support to achieve this control and to conduct interdisciplinary studies to determine the real situation is discussed. All compounds are listed in Table 19. PMID:14738198

  1. Ionic carbamate photoacid/photobase generators for the advancement of dual-tone photolithography

    Science.gov (United States)

    Hallett-Tapley, Geniece L.; Wee, Tse-Luen; Eldo, Joby; Jackson, Edward A.; Blackwell, James M.; Scaiano, Juan C.

    2012-03-01

    Current work in lithographic patterning has been carried out using 193 nm excitation sources, limiting the pitch division to approximately λ/2 and, thus, the advancement of Moore's law. Recently, double patterning has emerged as a potential extension of 193 nm techniques as two lines can be patterned in one exposure. In this contribution, the double patterning features of single component carbamate photoacid/photobase generators (PAG/PBG) are examined. At lower exposure doses, sulfonic acid is generated, while at higher doses, a photochemical rearrangement is initiated to activate the PBG. Optimally, at intermediate doses, photoacid and photobase components can exist concurrently resulting in the desired dual tone lithographic features. The energy required to initiate dual tone behavior can be tailored through co-added amine quenchers and carbamate concentration. Using ellipsometry, the energy required for the resists to have the first sign of photoacid generation (film dissolution), E0, and at the energy required for photobase activation (En) were determined, as this value dictates the ability to achieve the desired pitch division.

  2. Blackberry subjected to in vitro gastrointestinal digestion affords protection against Ethyl Carbamate-induced cytotoxicity.

    Science.gov (United States)

    Chen, Wei; Xu, Yang; Zhang, Lingxia; Su, Hongming; Zheng, Xiaodong

    2016-12-01

    Ethyl Carbamate (EC) was detected in many fermented foods. Previous studies indicated that frequent exposure to ethyl carbamate may increase the risk to suffer from cancers. Blackberry is rich in polyphenols and possesses potent antioxidant activity. This study aims to investigate the protective effect of blackberry homogenates produced before (BH) and after in vitro simulated gastrointestinal digestion (BD) on EC-induced toxicity in Caco-2 cells. Our results showed that blackberry homogenates after digestion (BD) was more effective than that before digestion (BH) in ameliorating EC-induced toxicity in Caco-2 cells. Further investigation revealed that BD remarkably attenuated EC-induced toxicity through restoring mitochondrial function, inhibiting glutathione depletion and decreasing overproduction of intracellular reactive oxygen species. Additionally, LC-MS result implied that the better protective capacity of BD may be related to the increased content of two anthocyanins (cyanidin-3-glucoside and cyanidin-3-dioxalyglucoside). Overall, the present study may give implication to prevent EC-induced health problem. PMID:27374576

  3. Formation of Carbamate Anions by the Gas-phase Reaction of Anilide Ions with CO2

    Science.gov (United States)

    Liu, Chongming; Nishshanka, Upul; Attygalle, Athula B.

    2016-05-01

    The anilide anion ( m/z 92) generated directly from aniline, or indirectly as a fragmentation product of deprotonated acetanilide, captures CO2 readily to form the carbamate anion ( m/z 136) in the collision cell, when CO2 is used as the collision gas in a tandem-quadrupole mass spectrometer. The gas-phase affinity of the anilide ion to CO2 is significantly higher than that of the phenoxide anion ( m/z 93), which adds to CO2 only very sluggishly. Our results suggest that the efficacy of CO2 capture depends on the natural charge density on the nitrogen atom, and relative nucleophilicity of the anilide anion. Generally, conjugate bases generated from aniline derivatives with proton affinities (PA) less than 350 kcal/mol do not tend to add CO2 to form gaseous carbamate ions. For example, the anion generated from p-methoxyaniline (PA = 367 kcal/mol) reacts significantly faster than that obtained from p-nitroaniline (PA = 343 kcal/mol). Although deprotonated p-aminobenzoic acid adds very poorly because the negative charge is now located primarily on the carboxylate group, it reacts more efficiently with CO2 if the carboxyl group is esterified. Moreover, mixture of CO2 and He as the collision gas was found to afford more efficient adduct formation than CO2 alone, or as mixtures made with nitrogen or argon, because helium acts as an effective "cooling" gas and reduces the internal energy of reactant ions.

  4. Carbamate and Pyrethroid Resistance in the Akron Strain of Anopheles gambiae

    Science.gov (United States)

    Mutunga, James M.; Anderson, Troy D.; Craft, Derek T.; Gross, Aaron D.; Swale, Daniel R.; Tong, Fan; Wong, Dawn M.; Carlier, Paul R.; Bloomquist, Jeffrey R.

    2015-01-01

    Insecticide resistance in the malaria vector, Anopheles gambiae is a serious problem, epitomized by the multi-resistant Akron strain, originally isolated in the country of Benin. Here we report resistance in this strain to pyrethroids and DDT (13-fold to 35-fold compared to the susceptible G3 strain), but surprisingly little resistance to etofenprox, a compound sometimes described as a “pseudo-pyrethroid.” There was also strong resistance to topically-applied commercial carbamates (45-fold to 81-fold), except for the oximes aldicarb and methomyl. Biochemical assays showed enhanced cytochrome P450 monooxygenase and carboxylesterase activity, but not that of glutathione-S-transferase. A series of substituted α,α,α,-trifluoroacetophenone oxime methylcarbamates were evaluated for enzyme inhibition potency and toxicity against G3 and Akron mosquitoes. The compound bearing an unsubstituted phenyl ring showed the greatest toxicity to mosquitoes of both strains. Low cross resistance in Akron was retained by all analogs in the series. Kinetic analysis of acetylcholinesterase activity and its inhibition by insecticides in the G3 strain showed inactivation rate constants greater than that of propoxur, and against Akron enzyme inactivation rate constants similar to that of aldicarb. However, inactivation rate constants against recombinant human AChE were essentially identical to that of the G3 strain. Thus, the acetophenone oxime carbamates described here, though potent insecticides that control resistant Akron mosquitoes, require further structural modification to attain acceptable selectivity and human safety. PMID:26047119

  5. Crystal structures of carbamate kinase from Giardia lamblia bound with citric acid and AMP-PNP.

    Directory of Open Access Journals (Sweden)

    Kap Lim

    Full Text Available The parasite Giardia lamblia utilizes the L-arginine dihydrolase pathway to generate ATP from L-arginine. Carbamate kinase (CK catalyzes the last step in this pathway, converting ADP and carbamoyl phosphate to ATP and ammonium carbamate. Because the L-arginine pathway is essential for G. lamblia survival and absent in high eukaryotes including humans, the enzyme is a potential target for drug development. We have determined two crystal structures of G. lamblia CK (glCK with bound ligands. One structure, in complex with a nonhydrolyzable ATP analog, adenosine 5'-adenylyl-β,γ-imidodiphosphate (AMP-PNP, was determined at 2.6 Å resolution. The second structure, in complex with citric acid bound in the postulated carbamoyl phosphate binding site, was determined in two slightly different states at 2.1 and 2.4 Å resolution. These structures reveal conformational flexibility of an auxiliary domain (amino acid residues 123-170, which exhibits open or closed conformations or structural disorder, depending on the bound ligand. The structures also reveal a smaller conformational change in a region associated the AMP-PNP adenine binding site. The protein residues involved in binding, together with a model of the transition state, suggest that catalysis follows an in-line, predominantly dissociative, phosphotransfer reaction mechanism, and that closure of the flexible auxiliary domain is required to protect the transition state from bulk solvent.

  6. 2011 EPA Pesticide General Permit (PGP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The 2011 EPA Pesticide General Permit (PGP) covers discharges of biological pesticides, and chemical pesticides that leave a residue, in areas where EPA is the...

  7. 76 FR 38160 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-06-29

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an active ingredient not included in any previously registered pesticide products. Pursuant to...

  8. 75 FR 71695 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-11-24

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency ACTION: Notice. SUMMARY: EPA has received applications to register new uses for pesticide products containing... Pesticide Programs (OPP) Regulatory Public Docket (7502P), Environmental Protection Agency,...

  9. 75 FR 24694 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-05

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: EPA has received applications to register pesticide products containing an active ingredient not included in any previously registered pesticide product. Pursuant to the...

  10. The P450 CYP6Z1 confers carbamate/pyrethroid cross-resistance in a major African malaria vector beside a novel carbamate-insensitive N485I acetylcholinesterase-1 mutation.

    Science.gov (United States)

    Ibrahim, Sulaiman S; Ndula, Miranda; Riveron, Jacob M; Irving, Helen; Wondji, Charles S

    2016-07-01

    Carbamates are increasingly used for vector control notably in areas with pyrethroid resistance. However, a cross-resistance between these insecticides in major malaria vectors such as Anopheles funestus could severely limit available resistance management options. Unfortunately, the molecular basis of such cross-resistance remains uncharacterized in An. funestus, preventing effective resistance management. Here, using a genomewide transcription profiling, we revealed that metabolic resistance through upregulation of cytochrome P450 genes is driving carbamate resistance. The P450s CYP6P9a, CYP6P9b and CYP6Z1 were the most upregulated detoxification genes in the multiple resistant mosquitoes. However, in silico docking simulations predicted CYP6Z1 to metabolize both pyrethroids and carbamates, whereas CYP6P9a and CYP6P9b were predicted to metabolize only the pyrethroids. Using recombinant enzyme metabolism and inhibition assays, we demonstrated that CYP6Z1 metabolizes bendiocarb and pyrethroids, whereas CYP6P9a and CYP6P9b metabolize only the pyrethroids. Other upregulated gene families in resistant mosquitoes included several cuticular protein genes suggesting a possible reduced penetration resistance mechanism. Investigation of the target-site resistance in acetylcholinesterase 1 (ace-1) gene detected and established the association between the new N485I mutation and bendiocarb resistance (odds ratio 7.3; P carbamate resistance and improve the design of effective resistance management strategies to control this malaria vector. PMID:27135886

  11. Synthesis and biological activity of beta-glucuronyl carbamate-based prodrugs of paclitaxel as potential candidates for ADEPT

    NARCIS (Netherlands)

    deBont, DBA; Leenders, RGG; Haisma, HJ; vanderMeulenMuileman, [No Value; Scheeren, HW

    1997-01-01

    The syntheses of prodrugs of paclitaxel, which can be used in ADEPT in order to target paclitaxel towards tumor cells, are described. The prodrugs 1 and 2a,b consist of a spacer molecule connected via a carbamate linkage to a beta-glucuronic acid. The spacer molecule is also connected via an ester l

  12. The Millimeter- and Submillimeter-Wave Spectrum of Methyl Carbamate [CH3OC(:O)NH2

    Science.gov (United States)

    Groner, Peter; Winnewisser, Manfred; Medvedev, Ivan R.; De Lucia, Frank C.; Herbst, Eric; Sastry, K. V. L. N.

    2007-03-01

    The rotational-torsional spectrum of the syn conformer of methyl carbamate [CH3OC(:O)NH2], an isomer of the essential amino acid glycine [NH2CH2C(:O)OH], has been recorded at room temperature in the spectral region from 79 to 371 GHz. Methyl carbamate possesses a methyl group internal rotor, which gives rise to A and E torsional substates, and associated splittings in the rotational spectrum. Almost 6000 new rotational transitions arising from the vibrational ground state have been assigned, about half of them belonging to the E torsional substate. Along with some earlier data, the newly measured lines were assigned and analyzed efficiently by the integration of two program packages: CAAARS, a suite for visual, interactive mouse-assisted line assignment of asymmetric rotor spectra; and ERHAM, a program that solves the effective Hamiltonian for molecules with up to two periodic large-amplitude internal motions. This Hamiltonian was used to fit 28 spectroscopic parameters for the methyl carbamate ground vibrational state to the observed line positions with a standard deviation of 0.081 MHz. With the determined spectroscopic constants and the available dipole moment components, we are able to predict the transition frequencies and intensities of many additional lines through 400 GHz. Methyl carbamate can now be searched for over a wide frequency range in appropriate interstellar sources such as hot molecular cores.

  13. Brain acetylcholinesterase of jaguar cichlid (Parachromis managuensis): From physicochemical and kinetic properties to its potential as biomarker of pesticides and metal ions.

    Science.gov (United States)

    Araújo, Marlyete Chagas de; Assis, Caio Rodrigo Dias; Silva, Luciano Clemente; Machado, Dijanah Cota; Silva, Kaline Catiely Campos; Lima, Ana Vitória Araújo; Carvalho, Luiz Bezerra; Bezerra, Ranilson de Souza; Oliveira, Maria Betânia Melo de

    2016-08-01

    This contribution aimed to characterize physicochemical and kinetic parameters of the brain cholinesterases (ChEs) from Parachromis managuensis and investigate the in vitro effects of pesticides and metal ions on its activity intending to propose as biomarker. This species is suitable for this investigation because (1) it was recently introduced in Brazil becoming invasive (no restrictions on capture) and (2) occupies the top of the food chain (being subject to bioaccumulation). The enzyme extract was exposed to 10 metal ions (Al(3+), Ba(2+), Cd(2+), Cu(2+), Hg(2+), Mg(2+), Mn(2+), Pb(2+), Fe(2+) and Zn(2+)) and ChEs selective inhibitors (BW284c51, Iso-OMPA, neostigmine and serine). The extract was also incubated with organophosphate (dichlorvos) and carbamate pesticides (carbaryl and carbofuran). Inhibition parameters (IC20, IC50 and ki) were determined. Selective inhibitors and kinetic parameters confirmed acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) -like as responsible for the ChE activities, most AChE. The IC50 values for pesticides were: 1.68μM (dichlorvos); 4.35μM (carbaryl) and 0.28μM (carbofuran). Most of the analyzed ions did not show significant effect at 1mM (p=0.05), whereas the following ions inhibited the enzyme activity in the order: Hg(2+)>Cu(2+)>Cd(2+)>Zn(2+). Mercury ion strongly inhibited the enzyme activity (IC20=0.7μM). The results about allow to conclude that P. managuensis brain AChE is a potential biomarker for heavy metals and pesticides under study, mainly for the carbamate carbofuran once it was capable to detect 6-fold lower levels than the limit concentration internationally recommended. PMID:27288599

  14. Evaluation System for Pesticides (ESPE). 1. Agricultural pesticides

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of S

  15. Evaluation System for Pesticides (ESPE). 1. Agricultural pesticides

    NARCIS (Netherlands)

    Emans HJB; Beek MA; Linders JBHJ

    1992-01-01

    In this report a risk assessment or evaluation system for agricultural pesticides is presented, which estimates the hazards for man and environment resulting from the use of these pesticides. The evaluation system has also been placed within the context of the Uniform System for the Evaluation of Su

  16. Intoxicación por plaguicidas Pesticide poisoning

    Directory of Open Access Journals (Sweden)

    A. Ferrer

    2003-01-01

    or by their chemical family (organochlorates, organophosphates, carbamates, pyrethroids, Bipyridilium compounds, inorganic salts…. All of them are biocides, which normally implies a high toxicity for humans, which has been a cause for concern since the mid-XX century due to the widespread and indiscriminate use of these products. Exposure to pesticides can have effects that are acute, chronic and long-term. Some organochlorate compounds (such as DDT were the first to be used in massive fumigations to fight malaria and have had to be banned because of their capacity for bioaccumulation and environmental persistence. The danger represented by the widespread presence of these agents has been demonstrated in numerous episodes of human toxic epidemics, producers of a high morbidity/mortality, described for nearly all chemical families: organochlorate insecticides and fungicides, organophosphate and carbamate insecticides, organomercurial fungicides and inorganic salts. These episodes have above all been caused through the ingestion of foodstuffs and in the occupational field. Other causes of health concern are their carcinogenic capacity and occasional reproductive alterations. The principal characteristics of some of the most relevant families are presented.

  17. [18F]Fluorobenzoyllysinepentanedioic Acid Carbamates: New Scaffolds for Positron Emission Tomography (PET) Imaging of Prostate-Specific Membrane Antigen (PSMA)

    OpenAIRE

    Yang, Xing; Mease, Ronnie C.; Pullambhatla, Mrudula; Lisok, Ala; Chen, Ying; Foss, Catherine A.; Wang, Yuchuan; Shallal, Hassan; Edelman, Hannah; Hoye, Adam T.; Attardo, Giorgio; Nimmagadda, Sridhar; Pomper, Martin G.

    2015-01-01

    Radiolabeled urea-based low-molecular weight inhibitors of the prostate-specific membrane antigen (PSMA) are under intense investigation as imaging and therapeutic agents for prostate and other cancers. In an effort to provide agents with less nontarget organ uptake than the ureas, we synthesized four 18F-labeled inhibitors of PSMA based on carbamate scaffolds. 4-Bromo-2-[18F]fluorobenzoyllysineoxypentanedioic acid (OPA) carbamate [18F]23 and 4-iodo-2-[18F]fluorobenzoyllysine OPA carbamate [1...

  18. Structural relaxation accompanied by photo-induced chromatic phase transition of polydiacetylenes with butylene-N-difluorophenyl carbamate side chains

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Yuuki; Sakamoto, Naoya; Kokado, Ryousuke; Kajimoto, Naoshi; Izumi, Yuuichiro [Department of Materials Science and Chemistry, Wakayama University, 930 Sakaedani, Wakayama (Japan); Itoh, Chihiro, E-mail: citoh@sys.wakayama-u.ac.jp [Department of Materials Science and Chemistry, Wakayama University, 930 Sakaedani, Wakayama (Japan)

    2013-01-15

    We have studied the phase transition of poly-5,7-dodecadiyne-1,12-diol bis[2,4-difluorophenyl carbamate] (PDA-2,4-DFPC) and poly-5,7-dodecadiyne-1,12-diol bis[3,4-difluorophenyl carbamate] (PDA-3,4-DFPC) by visible reflection spectroscopy and mid-infrared absorption spectroscopy. Both PDA-2,4-DFPC and PDA-3,4-DFPC show the reflection spectra characterized by a sharp peak at around 1.9 eV at room temperature. While PDA-3,4-DFPC shows thermochromic phase transition to the phase showing the reflection spectrum with a peak around 2.2 eV above 120 Degree-Sign C, PDA-2,4-DFPC shows no abrupt change of the reflection spectrum. However, PDA-2,4-DFPC shows drastic change of the reflection spectrum under 532-nm CW-laser excitation. Based on these results, we can draw the following two conclusions. First, the phase transition behavior of PDA can be controlled by modifying the side-chain structure. Second, we demonstrate that thermally inaccessible phase of PDA is induced by the photo-excitation. By measuring mid-infrared absorption of PDAs, we elucidated that conformational change of side chains is accompanied with the phase transition. Based on the results, we discussed the role of the side chain in the phase transition. - Highlights: Black-Right-Pointing-Pointer We have synthesized polydiacetylene (PDA) with difluorophenyl carbamate side chain. Black-Right-Pointing-Pointer PDAs show distinct phase transition (PT) depending on the side-chain structure. Black-Right-Pointing-Pointer PDA with 3,4-difluorophenyl carbamate shows PT by thermal stimulation. Black-Right-Pointing-Pointer However, PDA with 2,4-difluorophenyl carbamate shows PT only under photo-excitation.

  19. Choice of pesticide fate models

    International Nuclear Information System (INIS)

    The choice of a pesticide fate model at field scale is linked to the available input data. The article describes the available pesticide fate models at a field scale and the guidelines for the choice of the suitable model as function of the data input requested

  20. Quality control of pesticide products

    International Nuclear Information System (INIS)

    In light of an established need for more efficient analytical procedures, this publication, which documents the findings of an IAEA coordinated research project (CRP) on “Quality Control of Pesticide Products”, simplifies the existing protocol for pesticide analysis while simultaneously upholding existing standards of quality. This publication includes both a report on the development work done in the CRP and a training manual for use by pesticide analysis laboratories. Based on peer reviewed and internationally recognized methods published by the Association of Analytical Communities (AOAC) and the Collaborative International Pesticides Analytical Council (CIPAC), this report provides laboratories with versatile tools to enhance the analysis of pesticide chemicals and to extend the scope of available analytical repertoires. Adoption of the proposed analytical methodologies promises to reduce laboratories’ use of solvents and the time spent on reconfiguration and set-up of analytical equipment

  1. Children poisoning by carbamate: a descriptive study - doi:10.5020/18061230.2004.p193

    Directory of Open Access Journals (Sweden)

    Luiza Jane Eyre de Souza Vieira

    2012-01-01

    Full Text Available The study had as its aim to characterize the children under 5 years old, attended with exogenous poisoning by carbamate (popularly called “chumbinho” – “small shot” at an emergency hospital in Fortaleza and to relate the signs and symptoms detected in this type of poisoning. It concerned a descriptive study, with a sample of 65 children attended during the period of 1998 to 2000, in Fortaleza, Ceará. It was noticed that the most affected age group was of those with 1 to 3 years old, not being verified any significant difference between sexes. The most evident signs and symptoms were myosis, vomits, profuse perspiration and sialorrhea and the predominant treatment was the use of active coal. It is concluded, therefore, that there is a need of putting into effect the health education, calling the society’s attention to the risks of the inadequate “chumbinho” use in the domiciliar environment.

  2. A general method for tritium labelling of benzimidazole carbamates by catalytic exchange in dioxane solutions

    Energy Technology Data Exchange (ETDEWEB)

    Lacey, E. (Commonwealth Scientific and Industrial Research Organization, Glebe, NSW (Australia). Div. of Animal Health, McMaster Lab.); Dawson, M. (Sydney Univ. (Australia). Dept. of Pharmacy); Long, M.A.; Than, C. (New South Wales Univ., Kensington (Australia). School of Chemistry)

    1989-12-01

    Benzimidazole carbamates (BZCs) act as inhibitors of the tubulin-microtubule equilibria in eukaryotic organisms. Recently drug resistance to this class of compounds in helminth parasites has been shown to be due to a reduced ability of resistant tubulin to bind BZCs. In order to quantitate the nature of the tubulin-BZC interaction a general method for the specific tritium labelling of BZCs has been developed. The BZCs: mebendazole, oxfendazole, parbendazole, oxibendazole, albendazole and fenbendazole were labelled by catalytic exchange using palladium on calcium carbonate in pure dioxane at 60{sup 0}C under tritium gas. The position of label incorporation for tritiated albendazole was determined by tritium-NMR as the 4-position of benzimadazole nucleus. The yields for individual BZCs varied from 8 to 68% for a range of specific activity of 0.44 to 13.4 Ci/mmole. (author).

  3. Solubility improvement of an anthelmintic benzimidazole carbamate by association with dendrimers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, L.; Sigal, E.; Santo, M., E-mail: msanto@exa.unrc.edu.ar [Departamento de Fisica, Facultad de Ciencias Exactas Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto (Argentina); Otero, L.; Silber, J. J. [Departamento de Quimica. Facultad de Ciencias Exactas Fisicoquimicas y Naturales, Universidad Nacional de Rio Cuarto, Rio Cuarto (Argentina)

    2011-10-15

    The improvement of aqueous solubility of methyl (5-[propylthio]-1H-benzimidazole-2-yl) carbamate, albendazole (ABZ) using polyamidoamine (PAMAM) dendrimers as solubility enhancers was investigated. Full generation PAMAM dendrimers with amine terminal groups, (G3), with hydroxyl terminal groups (G3OH) and half generation PAMAM dendrimers with carboxylate terminal groups (G2.5 and G3.5), were chosen for this study. The nature of dendrimer-ABZ association was investigated by UV absorption, fluorescence emission measurements and by {sup 1}H-NMR spectroscopy. The results obtained show that these polymeric structures have the capacity to enhance the solubility of ABZ, both lipophilic and specific hydrogen bond interactions contributing to the guest-host association. Although all studied dendrimers have hydrophobic internal nanoenvironments with similar dimensions, their surfaces differ significantly and the nature and the localization of the interactions involved in ABZ-dendrimer association depend on the type of terminal groups. (author)

  4. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata.

    Science.gov (United States)

    Huang, Li-Si; He, Fei; Huang, Hui; Zhang, Xiao-Yong; Qi, Shu-Hua

    2012-01-01

    Five carbamate derivatives, obtucarbamates C and D (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (-)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (-)-4α,10β-aromadendranediol (8), (+)-4β,10β-aromadendranediol (9) were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. Compounds 1, 2, 6, and 7 were new, and their structures were established by spectroscopic analyses. Compounds 6 and 7 contained a taurine group that was rarely found in marine natural compounds, and 7 showed moderate antibacterial activity. The possible biosynthesis routes of 1-5 were conjectured. PMID:22423284

  5. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

    Directory of Open Access Journals (Sweden)

    Li-Si Huang

    2012-01-01

    Full Text Available Five carbamate derivatives, obtucarbamates C and D (1, 2, dimethyl ((carbonylbis(azanediylbis(2-methyl-5,1-phenylenedicarbamate (3, obtucarbamates A and B (4, 5, and four aromadendrane-type sesquiterpenoids, (+-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6, (−-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7, (−-4α,10β-aromadendranediol (8, (+-4β,10β-aromadendranediol (9 were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. Compounds 1, 2, 6, and 7 were new, and their structures were established by spectroscopic analyses. Compounds 6 and 7 contained a taurine group that was rarely found in marine natural compounds, and 7 showed moderate antibacterial activity. The possible biosynthesis routes of 1–5 were conjectured.

  6. PESTICIDE APPLICATION TECHNICS IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    Đuro Banaj

    2011-06-01

    Full Text Available The academic textbook Pesticide application tehnics improvement is the result of several-year recording theoretical models, numerous practical tests, and data collection relating to technical systems in plant protection and its environment in the narrowest sense. In this first edition, the authors cover the area they have dealt with for many years. The authors aimed to present complete and clear methods how to solve specific problems in the agricultural practice management, plant protection, and direct practice application – ‘‘Know- How'', with as many as possible useful data. References used, along with local ones, are mostly American and from Western Europe. This textbook is intended for those who already use the agricultural technique in plant protection and those who are just acquiring the basics of technical systems proper application in daily practice, regardless the size of the agricultural farm. The authors covered in details and explained some bases of physics logic, analysis, and synthesis of specific laws while using pesticides due to extremely importance in understanding the problem area.

  7. Determination of pesticides and pesticide degradates in filtered water by direct aqueous-injection liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    Sandstrom, Mark W.; Kanagy, Leslie K.; Anderson, Cyrissa A.; Kanagy, Christopher J.

    2016-01-11

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for determination of 229 pesticides compounds (113 pesticides and 116 pesticide degradates) in filtered water samples from stream and groundwater sites. The pesticides represent a broad range of chemical classes and were selected based on criteria such as current-use intensity, probability of occurrence in streams and groundwater, and toxicity to humans or aquatic organisms. More than half of the analytes are pesticide degradates. The method involves direct injection of a 100-microliter (μL) sample onto the LC-MS/MS without any sample preparation other than filtration. Samples are analyzed with two injections, one in electrospray ionization (ESI) positive mode and one in ESI negative mode, using dynamic multiple reaction monitoring (MRM) conditions, with two MRM transitions for each analyte. The LC-MS/MS instrument parameters were optimized for highest sensitivity for the most analytes. This report describes the analytical method and presents characteristics of the method validation including bias and variability, detection levels, and holding-time studies.

  8. Determination of pesticides and pesticide degradates in filtered water by direct aqueous-injection liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    Sandstrom, Mark W.; Kanagy, Leslie K.; Anderson, Cyrissa A.; Kanagy, Christopher J.

    2016-01-01

    A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for determination of 229 pesticides compounds (113 pesticides and 116 pesticide degradates) in filtered water samples from stream and groundwater sites. The pesticides represent a broad range of chemical classes and were selected based on criteria such as current-use intensity, probability of occurrence in streams and groundwater, and toxicity to humans or aquatic organisms. More than half of the analytes are pesticide degradates. The method involves direct injection of a 100-microliter (μL) sample onto the LC-MS/MS without any sample preparation other than filtration. Samples are analyzed with two injections, one in electrospray ionization (ESI) positive mode and one in ESI negative mode, using dynamic multiple reaction monitoring (MRM) conditions, with two MRM transitions for each analyte. The LC-MS/MS instrument parameters were optimized for highest sensitivity for the most analytes. This report describes the analytical method and presents characteristics of the method validation including bias and variability, detection levels, and holding-time studies.

  9. Determination of pesticide in ground and surface water samples and perception of farmers about pesticides in Sindh

    International Nuclear Information System (INIS)

    The continuous monitoring of pesticide residues in our food, drinking water, environment and biosphere at large is needed for creating awareness for the trends of level of contamination and building up a data base upon which, future plan could be decided. In this paper monitoring requirements regarding the instrumentations, valid sampling, analytical protocols and its purpose are discussed in detail. Twenty nine water samples were analyzed and 22 were found contaminated with detectable level of 5 pesticides. These samples were found contaminated in the range of 0.0005-0.054 micro g/L. The percentage of detection of Chloropyriphos, Malathion, Dimethoate, Cypermethrin, and Endosulfan was respectively 7%, 14%. 17.8%, 35.8% and 25%. However, none of the samples were found above their Maximum Acceptable Concentrate (MAC) i.e. 0.1 micro g/L and 0.5 micro g/L for single and number of insecticides respectively set by EEC (European Economic Commission). Moreover, a survey of farmers' perceptions in respect of effects on their health with pesticide exposure was conducted to find out farmers' perception for the use of pesticides and how these may affect on their health with, identification of key issues those are relevant to farmers' health for further training to increase farmer's awareness about the use of pesticides. (author)

  10. Sprinkler irrigation-pesticide best management systems

    OpenAIRE

    Ranjha, A. Y.; Peralta, R. C.; Hill, R. W.; Requena, A. M.; Deer, H. M.; Ehteshami, M.

    1992-01-01

    The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduce...

  11. Fact Sheets on Pesticides in Schools.

    Science.gov (United States)

    National Coalition against the Misuse of Pesticides, Washington, DC.

    This document consists of a collection of fact sheets about the use of pesticides in schools and how to reduce it. The sheets are: (1) "Alternatives to Using Pesticides in Schools: What Is Integrated Pest Management?"; (2) "Health Effects of 48 Commonly Used Pesticides in Schools"; (3) "The Schooling of State Pesticide Laws--2002 Update: A Review…

  12. Pesticide Productivity: Of Bugs and Biases

    OpenAIRE

    Norwood, F. Bailey; Marra, Michele C.

    2003-01-01

    Pesticide productivity is both important and difficult to measure. Typically, pesticide marginal products are estimated without information on the pest pressure. Three theoretical models are developed which suggest absence of such information may cause an underestimation of pesticide productivity. Using application frequency variables as a proxy for pest populations, we show that pesticide marginal products are higher when pest pressure is accounted for.

  13. Novel Cholinesterase Inhibitors Based on O-Aromatic N,N-Disubstituted Carbamates and Thiocarbamates

    Directory of Open Access Journals (Sweden)

    Martin Krátký

    2016-02-01

    Full Text Available Based on the presence of carbamoyl moiety, twenty salicylanilide N,N-disubstituted (thiocarbamates were investigated using Ellman’s method for their ability to inhibit acetylcholinesterase (AChE and butyrylcholinesterase (BChE. O-Aromatic (thiocarbamates exhibited weak to moderate inhibition of both cholinesterases with IC50 values within the range of 1.60 to 311.0 µM. IC50 values for BChE were mostly lower than those obtained for AChE; four derivatives showed distinct selectivity for BChE. All of the (thiocarbamates produced a stronger inhibition of AChE than rivastigmine, and five of them inhibited BChE more effectively than both established drugs rivastigmine and galantamine. In general, 5-chloro-2-hydroxy-N-[4-(trifluoromethyl-phenyl]benzamide, 2-hydroxy-N-phenylbenzamide as well as N-methyl-N-phenyl carbamate derivatives led to the more potent inhibition. O-{4-Chloro-2-[(4-chlorophenylcarbamoyl]phenyl} dimethylcarbamothioate was identified as the most effective AChE inhibitor (IC50 = 38.98 µM, while 2-(phenylcarbamoylphenyl diphenylcarbamate produced the lowest IC50 value for BChE (1.60 µM. Results from molecular docking studies suggest that carbamate compounds, especially N,N-diphenyl substituted representatives with considerable portion of aromatic moieties may work as non-covalent inhibitors displaying many interactions at peripheral anionic sites of both enzymes. Mild cytotoxicity for HepG2 cells and consequent satisfactory calculated selectivity indexes qualify several derivatives for further optimization.

  14. Physiological effects of work stress and pesticide exposure in tree planting by British Columbia silviculture workers.

    Science.gov (United States)

    Robinson, D G; Trites, D G; Banister, E W

    1993-08-01

    Tree planters in British Columbia have reported symptoms that are congruent with musculoskeletal stress and organophosphate or carbamate pesticide intoxication. The purpose of this research was to determine the existence of any physiological or biochemical correlate supporting the existence of these potential hazards in tree planting. Worker's health complaints were assessed from regularly distributed questionnaires. Blood samples were obtained from 14 male and three female Canadian subjects before and after tree planting work on 10 occasions throughout a tree planting season. The strenuous physical challenge of tree planting was confirmed by a significant elevation of serum enzyme activity (ESEA) at the beginning of the season, which did not return to a normal level during the remainder of the season. Significant (p < or = 0.05) inhibition of erythrocyte acetylcholinesterase activity (AChE) postwork was observed in 15.9% of individuals, and a significant group mean prework-postwork difference of AChE or plasma pseudocholinesterase (PChE) was observed on two days of testing, indicating a potential toxicological hazard from pesticide absorption. No correlation was found between the degree of ESEA or cholinesterase inhibition and the number of health complaints. PMID:8365393

  15. The Methylene Alkoxy Carbamate Self-Immolative Unit: Utilization for the Targeted Delivery of Alcohol-Containing Payloads with Antibody-Drug Conjugates.

    Science.gov (United States)

    Kolakowski, Robert V; Haelsig, Karl T; Emmerton, Kim K; Leiske, Chris I; Miyamoto, Jamie B; Cochran, Julia H; Lyon, Robert P; Senter, Peter D; Jeffrey, Scott C

    2016-07-01

    A strategy for the conjugation of alcohol-containing payloads to antibodies has been developed and involves the methylene alkoxy carbamate (MAC) self-immolative unit. A series of MAC β-glucuronide model constructs were prepared to evaluate stability and enzymatic release, and the results demonstrated high stability at physiological pH in a substitution-dependent manner. All the MAC model compounds efficiently released alcohol drug surrogates under the action of β-glucuronidase. To assess the MAC technology for ADCs, the potent microtubule-disrupting agent auristatin E (AE) was incorporated through the norephedrine alcohol. Conjugation of the MAC β-glucuronide AE drug linker to the anti-CD30 antibody cAC10, and an IgG control antibody, gave potent and immunologically specific activities in vitro and in vivo. These studies validate the MAC self-immolative unit for alcohol-containing payloads within ADCs, a class that has not been widely exploited. PMID:27198854

  16. Soil column leaching of pesticides.

    Science.gov (United States)

    Katagi, Toshiyuki

    2013-01-01

    In this review, I address the practical and theoretical aspects of pesticide soil mobility.I also address the methods used to measure mobility, and the factors that influence it, and I summarize the data that have been published on the column leaching of pesticides.Pesticides that enter the unsaturated soil profile are transported downwards by the water flux, and are adsorbed, desorbed, and/or degraded as they pass through the soil. The rate of passage of a pesticide through the soil depends on the properties of the pesticide, the properties of the soil and the prevailing environmental conditions.Because large amounts of many different pesticides are used around the world, they and their degradates may sometimes contaminate groundwater at unacceptable levels.It is for this reason that assessing the transport behavior and soil mobility of pesticides before they are sold into commerce is important and is one indispensable element that regulators use to assess probable pesticide safety. Both elementary soil column leaching and sophisticated outdoor lysimeter studies are performed to measure the leaching potential for pesticides; the latter approach more reliably reflects probable field behavior, but the former is useful to initially profile a pesticide for soil mobility potential.Soil is physically heterogeneous. The structure of soil varies both vertically and laterally, and this variability affects the complex flow of water through the soil profile, making it difficult to predict with accuracy. In addition, macropores exist in soils and further add to the complexity of how water flow occurs. The degree to which soil is tilled, the density of vegetation on the surface, and the type and amounts of organic soil amendments that are added to soil further affect the movement rate of water through soil, the character of soil adsorption sites and the microbial populations that exist in the soil. Parameters that most influence the rate of pesticide mobility in soil are

  17. PPA-SiO2 Catalyzed Multi-component Synthesis of N-[α-(β-Hydroxy-α-naphthyl)(benzyl)]O-Alkyl Carbamate Derivatives

    Institute of Scientific and Technical Information of China (English)

    SHATERIAN,Hamid Reza; HOSSEINIAN,Asghar; GHASHANG,Majid

    2009-01-01

    Silica-supported polyphosphoric acid (PPA-SiO2) was found to be an efficient catalyst for the multi-component condensation reaction of benzaldehydes,2-naphthol,and methyl/benzyl carbamate to afford the corresponding N-[α-(β-hydroxy-α-naphthyl)(benzyl)]O-alkyl carbamate derivatives in good to excellent yields.This new approach consistently has the advantage of short reaction time,high conversions,clean reaction profiles,and simple experimental and work-up procedures.

  18. Trabalho rural e fatores de risco associados ao regime de uso de agrotóxicos em Minas Gerais, Brasil Rural work and risk factors associated with pesticide use in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Wagner Soares

    2003-08-01

    Full Text Available O objetivo deste artigo foi caracterizar o processo do trabalho rural em nove municípios de Minas Gerais, considerando indicadores sócio-demográficos, a estrutura agrária dos estabelecimentos rurais, práticas de trabalho relacionadas ao uso de agrotóxicos e, a intoxicação associada a seu uso. Os dados foram obtidos de uma pesquisa realizada pela Fundação Jorge Duprat Figueiredo, de Segurança e Medicina do Trabalho, que aplicou um questionário a 1.064 trabalhadores rurais, entre os anos de 1991 a 2000. Por meio de uma regressão logística, foram obtidos os fatores de risco associados à intoxicação por agrotóxicos dos grupos organofosforados e carbamatos. Cerca de 50% dos entrevistados se encontravam ao menos moderadamente intoxicados. Os fatores de risco encontrados foram: ter o último contato a menos de duas semanas com agrotóxicos; não usar proteção; ser orientado pelo vendedor; citar organofosforado ou carbamato como agrotóxico principal e trabalhar nos municípios de Teófoli Otoni, Guidoval ou Piraúba. Os resultados apontam para o alto grau de risco de agravos à saúde a que estão sujeitos trabalhadores rurais em contato com agrotóxicos.This paper aimed to characterize the rural work process in nine counties in Minas Gerais State, considering socio-demographic indicators, the land tenure structure of farm operations, and work practices related to pesticide use and poisoning Data were obtained through the Jorge Duprat Figueiredo Foundation for Workers' Safety and Occupational Medicine, which applied a questionnaire to 1,064 rural workers from 1991 to 2000. Through a logistic regression, risk factors associated with pesticide poisoning were obtained for the carbamate and organophosphate groups. Some 50% of interviewees displayed at least moderate pesticide toxicity. Risk factors for pesticide poisoning were: last contact with pesticides less than two weeks before the blood cholinesterase test; no use of personal

  19. Health and environmental hazards of pesticides.

    Science.gov (United States)

    Iyaniwura, T T

    1991-01-01

    The increase in world population and in demand for food and economic crops has put a pesticide burden on man and the environment. Pesticide residues from vector control and agricultural uses contaminate the terrestrial and aquatic surroundings and contribute to the pollution problem of the environment. Various human toxicoses have resulted from pesticide use. The major pathogenic pesticides are chlorinated hydrocarbons and organophosphates. With careful and enlightened use, pesticide toxicity, to both man and the environment, could be significantly reduced.

  20. 75 FR 13284 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2010-03-19

    ... AGENCY Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue Committee AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: Pursuant to the Federal Advisory Committee Act, EPA's Office of Pesticide Programs is inviting nominations of qualified...

  1. Pesticide use and application: An Indian scenario

    Energy Technology Data Exchange (ETDEWEB)

    Abhilash, P.C., E-mail: pcabhilash@gmail.com [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow 226001, Uttar Pradesh (India); Singh, Nandita, E-mail: nanditasingh8@yahoo.co.in [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow 226001, Uttar Pradesh (India)

    2009-06-15

    Agricultural development continues to remain the most important objective of Indian planning and policy. In the process of development of agriculture, pesticides have become an important tool as a plant protection agent for boosting food production. Further, pesticides play a significant role by keeping many dreadful diseases. However, exposure to pesticides both occupationally and environmentally causes a range of human health problems. It has been observed that the pesticides exposures are increasingly linked to immune suppression, hormone disruption, diminished intelligence, reproductive abnormalities and cancer. Currently, India is the largest producer of pesticides in Asia and ranks twelfth in the world for the use of pesticides. A vast majority of the population in India is engaged in agriculture and is therefore exposed to the pesticides used in agriculture. Although Indian average consumption of pesticide is far lower than many other developed economies, the problem of pesticide residue is very high in India. Pesticide residue in several crops has also affected the export of agricultural commodities in the last few years. In this context, pesticide safety, regulation of pesticide use, proper application technologies, and integrated pest management are some of the key strategies for minimizing human exposure to pesticides. There is a dearth of studies related to these issues in India. Therefore, the thrust of this paper was to review the technology of application of pesticides in India and recommend future strategies for the rational use of pesticides and minimizing the problems related to health and environment.

  2. Radiation induced pesticidal microbes

    International Nuclear Information System (INIS)

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants

  3. Pesticide reducing instruments

    DEFF Research Database (Denmark)

    Jacobsen, Lars-Bo; Jensen, Jørgen Dejgård; Andersen, Martin;

    2005-01-01

    the cost and to calculate general economic and sectoral consequences. This CGE model is linked to an agricultural sector model calculating the optimal use of land, and the agricultural sector model is then linked to a biological agent based simulation model (ABM) calculating changes in the population......-mentioned models and tools. All three scenarios are constructed such that they result in the same welfare implication (measured by national consumption in the CGE model). The scenarios are: 1) pesticide taxes resulting in a 25 percent overall reduction; 2) use of unsprayed field margins, resulting in the same...... for improving bio-diversity and securing drinking water. That is, combining economic modeling with physical biological modeling and geological evaluation allows us to select unsprayed field margins as the most effective instrument. Sensitivity analysis conducted on bio-diversity suggest that this result...

  4. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  5. Determination of Mineral, Trace Element, and Pesticide Levels in Honey Samples Originating from Different Regions of Malaysia Compared to Manuka Honey

    Directory of Open Access Journals (Sweden)

    Mohammed Moniruzzaman

    2014-01-01

    Full Text Available The present study was undertaken to determine the content of six minerals, five trace elements, and ten pesticide residues in honeys originating from different regions of Malaysia. Calcium (Ca, magnesium (Mg, iron (Fe, and zinc (Zn were analyzed by flame atomic absorption spectrometry (FAAS, while sodium (Na and potassium (K were analyzed by flame emission spectrometry (FAES. Trace elements such as arsenic (As, lead (Pb, cadmium (Cd, copper (Cu, and cobalt (Co were analyzed by graphite furnace atomic absorption spectrometry (GFAAS following the microwave digestion of honey. High mineral contents were observed in the investigated honeys with K, Na, Ca, and Fe being the most abundant elements (mean concentrations of 1349.34, 236.80, 183.67, and 162.31 mg/kg, resp.. The concentrations of the trace elements were within the recommended limits, indicating that the honeys were of good quality. Principal component analysis reveals good discrimination between the different honey samples. The pesticide analysis for the presence of organophosphorus and carbamates was performed by high performance liquid chromatography (HPLC. No pesticide residues were detected in any of the investigated honey samples, indicating that the honeys were pure. Our study reveals that Malaysian honeys are rich sources of minerals with trace elements present within permissible limits and that they are free from pesticide contamination.

  6. Non-Hodgkin Lymphoma and Occupational Exposure to Agricultural Pesticide Chemical Groups and Active Ingredients: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Leah Schinasi

    2014-04-01

    Full Text Available This paper describes results from a systematic review and a series of meta-analyses of nearly three decades worth of epidemiologic research on the relationship between non-Hodgkin lymphoma (NHL and occupational exposure to agricultural pesticide active ingredients and chemical groups. Estimates of associations of NHL with 21 pesticide chemical groups and 80 active ingredients were extracted from 44 papers, all of which reported results from analyses of studies conducted in high-income countries. Random effects meta-analyses showed that phenoxy herbicides, carbamate insecticides, organophosphorus insecticides and the active ingredient lindane, an organochlorine insecticide, were positively associated with NHL. In a handful of papers, associations between pesticides and NHL subtypes were reported; B cell lymphoma was positively associated with phenoxy herbicides and the organophosphorus herbicide glyphosate. Diffuse large B-cell lymphoma was positively associated with phenoxy herbicide exposure. Despite compelling evidence that NHL is associated with certain chemicals, this review indicates the need for investigations of a larger variety of pesticides in more geographic areas, especially in low- and middle-income countries, which, despite producing a large portion of the world’s agriculture, were missing in the literature that were reviewed.

  7. Nation-wide assessment of pesticide leaching to groundwater in Germany: comparison of indicator and metamodel approaches.

    Science.gov (United States)

    Vanderborght, Jan; Kuhr, Petra; Tiktak, Aaldrik; Wendland, Frank; Vereecken, Harry; Corsten, Karin

    2010-05-01

    In order to estimate the risk op groundwater contamination by surface applied pesticides, the fate of pesticides in the unsaturated zone needs to be evaluated. Process models that describe relevant processes such as transport of dissolved pesticides, sorption, degradation and root uptake, in combination with water and heat fluxes in the soil have been developed and used for regulatory purposes. Regional assessments are required to indentify regions with higher risks of groundwater contamination. A major problem for the application of process models for a regional, EU-member state, or EU-scale assessment of pesticide leaching risk is the availability of regional databases of input parameters and boundary conditions that are required to run these models. Therefore, procedures that can assess pesticide leaching risk based on databases with regional coverage are required. In this presentation, we compare two different approaches for a regional estimation of pesticide leaching risk to groundwater in Germany. The first method uses an indicator approach to evaluate the risk of pesticide leaching as a function of a number of categorized soil, climate and pesticide properties. The result is a map of categorized risks. In the second approach, a metamodel is used to estimate the leached pesticide concentrations based on nation-wide available data of yearly average precipitation, temperature, soil organic matter content, soil texture, and pesticide parameters. The metamodel represents a synthesis of relations between climate, soil, and pesticide properties on one hand and leaching concentrations that are simulated by a more detailed process model on the other hand. The obtained maps of leaching risks and leaching concentrations were compared with the locations of anomynized pesticide findings in groundwater. The use of databases of pesticide findings in groundwater for the validation of leaching risks assessments is discussed.

  8. Novel Preparation of Methoxy Carbamates of 1-Protected Indole- 3-methylamines as Precursor of Indole-3-methylamine

    Institute of Scientific and Technical Information of China (English)

    SONG,Hao; XIN,Jun-Guo; WANG,Yin; CHEN,Wei; YANG,Jun; QIN,Yong

    2004-01-01

    @@ Indole-3-methylamine (1) has been well demonstrated to be a very useful intermediate as a pharmaceutical building block and starting material for syntheses of phytoalexins.[1] The instability of indole-3-methylamine (1) has undoubtedly restricted its application in synthetic chemistry. Hofmann rearrangement that directly converts carboxamides to alky carbamates in the presence of alcohol required unexceptionally a strong base,[2] which devaluated the possible usefulness of Hofmann rearrangement in preparation of base sensitive amines, especially for the preparation of unstable indole-3-methylamine (1). Herein we would like to report a convenient method for the preparation of alkyl carbamates of 1-protected indole-3-methylamines (4) via the diacetoxyiodobenzene (DIB) promoted Hofmann rearrangement under neutral condition.

  9. 氨基甲酸酯清洁合成技术进展%Progress in clean synthesis of carbamates

    Institute of Scientific and Technical Information of China (English)

    谭学峰; 王越; 胡静; 马飞; 王公应

    2012-01-01

    综述了氨基甲酸酯清洁合成技术的发展现状和趋势,并对所用催化剂体系做了详细评述,认为碳酸酯胺解法是最具产业化前景的氨基甲酸酯清洁合成路线,高活性催化剂结合适宜的工艺流程是产业化成功的关键.%Recent progress and trends in clean synthesis of carbamates were reviewed, including a detail commentary on the catalyst systems. Ammonolysis of dimethyl carbonate (DMC) was considered to be the most promising industrial route for clean synthesis of carbamates. It was believed that developing high activity catalyst with suitable process would be the key to the industrial success.

  10. Solid-phase extraction of flavonoids in honey samples using carbamate-embedded triacontyl-modified silica sorbent.

    Science.gov (United States)

    Liu, Houmei; Zhang, Mingliang; Guo, Yong; Qiu, Hongdeng

    2016-08-01

    In this study, carbamate-embedded triacontyl-modified silica (Sil-CBM-C30) is successfully prepared and used as an efficient sorbent for solid-phase extraction. The extraction performance of the resultant sorbent is evaluated with five flavonoids including myricetin, quercetin, luteolin, kaempferol and isorhamnetin. Main parameters, which affect extraction efficiencies, are carefully investigated and optimized. Comparative experiments between Sil-CBM-C30 and commercial C18 sorbents indicate that the extraction efficiencies of the former one surpass the latter one. The modification of carbamate-embedded triacontyl group on surface of silica causes analytes extracted by hydrophobic, hydrogen bonding and π-π interactions. Under optimal conditions, good linearities and satisfied LODs and LOQs are achieved. The SPE-HPLC-DAD method is successfully developed and applied for the honey sample analysis. PMID:26988475

  11. [A case of carbamate poisoning in which GCMS was useful to identify causal substance and to decide the appropriate treatment].

    Science.gov (United States)

    Kinoshita, H; Hirose, Y; Tanaka, T; Hori, Y; Nakajima, M; Fujisawa, M; Oseki, M

    2001-10-01

    We often have cases of insecticide poisoning where the patient is unconscious and the causal substances are unknown. We report an 83-year-old unconscious man who had apparently ingested several agricultural chemicals, possibly organophosphate or carbamate. According to his family, there were three kinds of containers of agricultural chemicals with their caps opened around him. When he was transferred to our hospital, he presented hypertension, hypersalivation, and muscle fasciculation. His pupils were markedly miotic. In order to identify the substances ingested we used a gas chromatographymass spectrometer (GCMS) using his gastric content. Within 30 minutes we were able to identify the causal substance as methomyl, one of the popular carbamates, thereby eliminating the need to use pralidoxime (PAM). GCMS makes it possible to identify unknown substances quickly and accurately and is therefore extremely useful in deciding the appropriate treatment.

  12. 77 FR 64990 - Pesticide Program Dialogue Committee; Request for Nominations to the Pesticide Program Dialogue...

    Science.gov (United States)

    2012-10-24

    ... groups; pesticide users and growers; animal rights groups; pest consultants; State, local, and tribal...: Environmental/public interest and animal rights groups; farm worker organizations; pesticide industry and...

  13. Pesticide movement and water management

    OpenAIRE

    Ehteshami, Majid; Peralta, R C

    1989-01-01

    Agricultural chemicals are essential components of agricultural production systems in the United states. Pesticides control weeds, insects, and have had an important role in increasing agricultural productivity in the last 50 years, despite diminishing crop land acreage. The benefits of chemicals use options in agriculture must be balanced against potential contamination of surface water and ground water resources. This study shows the effect of water management practices on pesticide movemen...

  14. Pesticidal residues in animal tissues

    Science.gov (United States)

    DeWitt, J.B.; Menzie, C.M.; Adomaitis, V.A.; Reichel, W.L.

    1960-01-01

    Tests with penned starlings, rats, pheasants, and ducks indicated that each species differs in sensitivity to the various pesticides. Residues in tissues are proportional to the degree of exposure during area treatment and they are also found in animals shot six or more months after treatment. The presence of more than 20-30 ppm of DDT, 20 ppm of chlordan, and 6-20 ppm of heptachlor epoxide in quail tissues indicated that the birds had ingested lethal dosages of the pesticides.

  15. Effect of two formulations of benzimidazole carbamates on the viability of cysts of Echinococcus granulosus in vivo

    OpenAIRE

    Daniel-Mwuambete K.; Ponce-Gordo F.; Torrado J.; Torrado S.; Cuesta-Bandera C.

    2003-01-01

    Two different preparations, solution and suspension, of three benzimidazole carbamate drugs, mebendazole, albendazole and ricobendazole, were compared by analyzing their in vivo activity against Echinococcus granulosus cysts in a mouse model. Polyvinylpyrrolidone was used for the elaboration of drug solutions and these formulations manifested better results in terms of reduction of number of viable hydatid cysts in mice than the reference drug suspensions. The effect was more prominent on meb...

  16. Movement of pesticides from the site of application

    International Nuclear Information System (INIS)

    Important among the data needed to reduce the environmental risks potentially associated with pesticide use is a clear understanding of environmental processes. Much information has been accumulated and this is discussed with special reference to the research being carried out by scientists of the Agricultural Research Service of the United States Department of Agriculture at Beltsville. Physical and chemical properties are important in predicting the environmental fate of a pesticide. Routes of dissipation from the site of application will be influenced by the agricultural system and the method of application. Causes of loss include runoff and a three year study showed the extent of herbicide runoff to the Wye River Estuary. Potential contamination of groundwater by leaching has been recognized as a problem in certain cases and its extent and causes are being extensively studied. Volatilization may be a significant source of loss. Two important factors are the vapour pressure of the pesticide and the nature of the surface. Pesticide volatilization was measured using specially designed sampling equipment. Losses from dry soil surfaces were much smaller than the rapid losses from moist surfaces. Losses were predictable in terms of the vapour pressure of the compound and its interaction with surfaces. Atmospheric movement is important in the transport of pesticides. They may be redeposited on the Earth's surface by a number of mechanisms including rainfall, fog and snow or be adsorbed on particulate matter. A specially constructed sampler was used to collect the liquid and vapour phases of fog. Pesticides, their alteration products, plasticizers, flame retardants, industrial chemicals and combustion products were found in fog samples collected in Maryland and California. Distribution between liquid and vapour phases was not in accordance with Henry's Law and experiments are in progress to measure Henry's Law constants to validate these observations. 26 refs, 2 figs

  17. Use of pesticides in Kazakhstan

    International Nuclear Information System (INIS)

    The Republic of Kazakhstan has 210 regional stations, 19 provincial stations and one co-ordinating government research and production station, all known as Republic Stations for Plant Protection. These stations have the following functions: they control pesticide use and development, and monitor pest populations; they inform and teach farmers the methods for controlling insect pests, diseases and weeds, and the rules for safe pesticide use; and they continually monitor the presence or spread of any adverse effects in order to make short and long term prognoses, which are then used to determine the pesticide requirements. The major functions of these government stations is to control the timely distribution of pesticides and their safe and timely application, so that regulations for their use can be monitored and control over technology maintained. The co-ordinating station evaluates all projects, provides documentation on the use and storage of pesticides, controls field trials carried out by foreign companies on the Republic's territory and regulates pesticide usage during campaigns against insect pests, diseases and weeds. The regional and district subdivisions of these government stations promote integrated pest management for protecting harvests. (author)

  18. Pesticides' influence on wine fermentation.

    Science.gov (United States)

    Caboni, Pierluigi; Cabras, Paolo

    2010-01-01

    Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues.

  19. Pesticides' influence on wine fermentation.

    Science.gov (United States)

    Caboni, Pierluigi; Cabras, Paolo

    2010-01-01

    Wine quality strongly depends on the grape quality. To obtain high-quality wines, it is necessary to process healthy grapes at the correct ripeness stage and for this reason the farmer has to be especially careful in the prevention of parasite attacks on the grapevine. The most common fungal diseases affecting grape quality are downy and powdery mildew (Plasmopara viticola and Uncinula necator), and gray mold (Botrytis cinerea). On the other hand, the most dangerous insects are the grape moth (Lobesia botrana), vine mealybug (Planococcus ficus), and the citrus mealybug (Planococcus citri). Farmers fight grape diseases and insects applying pesticides that can be found at harvest time on grapes. The persistence of pesticides depends on the chemical characteristic of the active ingredients as well as on photodegradation, thermodegradation, codistillation, and enzymatic degradation. The pesticide residues on grapes can be transferred to the must and this can influence the selection and development of yeast strains. Moreover, yeasts can also influence the levels of the pesticides in the wine by reducing or adsorbing them on lees. During the fermentative process, yeasts can cause the disappearance of pesticide residues by degradation or absorption at the end of the fermentation when yeasts are deposited as lees. In this chapter, we reviewed the effect of commonly used herbicides, insecticides, and fungicides on yeasts. We also studied the effect of alcoholic and malolactic fermentation on pesticide residues. PMID:20610173

  20. Novel chiral stationary phases based on peptoid combining a quinine/quinidine moiety through a C9-position carbamate group.

    Science.gov (United States)

    Wu, Haibo; Wang, Dongqiang; Song, Guangjun; Ke, Yanxiong; Liang, Xinmiao

    2014-04-01

    By connecting a quinine or quinidine moiety to the peptoid chain through the C9-position carbamate group, we synthesized two new chiral selectors. After immobilizing them onto 3-mercaptopropyl-modified silica gel, two novel chiral stationary phases were prepared. With neutral, acid, and basic chiral compounds as analytes, we evaluated these two stationary phases and compared their chromatographic performance with chiral columns based on quinine tert-butyl carbamate and the previous peptoid. From the resolution of neutral and basic analytes under normal-phase mode, it was found that the new stationary phases exhibited much better enantioselectivity than the quinine tert-butyl carbamate column; the peptoid moiety played an important role in enantiorecognition, which controlled the elution orders of enantiomers; the assisting role of the cinchona alkaloid moieties was observed in some separations. Under acid polar organic phase mode, it was proved that cinchona alkaloid moieties introduced excellent enantiorecognitions for chiral acid compounds; in some separations, the peptoid moiety affected enantioseparations as well. Overall, chiral moieties with specific enantioselectivity were demonstrated to improve the performance of peptoid chiral stationary phase efficiently.

  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 <= 10% of the meatball before exhibiting acute signs of toxicity. Fenthion-exposed owls and kestrels displayed a wide spectrum of meatball consumption (<10100%). Significant brain ChE inhibition was observed in dead and surviving kestrels exposed to fenthion and carbofuran and dead owls exposed to fenthion (P < 0.0001). Brain ChE activity of owls exposed to carbofuran that survived was not different from that of controls (P = 0.25). Data suggest: (1) slow feeding on a carbamate-contaminated item may provide limited protection from the toxicity of the chemical at certain rates of exposure; (2) the degree of ChE inhibition at neuromuscular junctions may be critical in determining the sensitivity of a species to a carbamate insecticide; (3) sensitivity may be a function of the ChE affinity for the carbamate inhibitor; and (4) the importance of neuromuscular junction ChE depression in determining the sensitivity of an animal may be species-specific.

  2. Precipitation of calcium carbonate from a calcium acetate and ammonium carbamate batch system

    Science.gov (United States)

    Prah, J.; Maček, J.; Dražič, G.

    2011-06-01

    In this paper, we report a novel approach for preparing precipitated calcium carbonate using solutions of ammonium carbamate and calcium acetate as the sources of calcium and carbon dioxide, respectively. Two different concentrations of the starting solutions at three different temperatures (15, 25 and 50 °C) were used for the reaction. The influence of temperature and concentration on the polymorphism and the resulting morphology of calcium carbonate are discussed. The most important parameter for controlling a particular crystal structure and precipitate morphology were the concentrations of the initial solutions. When initial solutions with lower concentrations were used, the crystal form of the precipitate changed with time. Regardless the different polymorphism at different temperatures, after one day only the calcite form was detected in all samples, regardless of at which temperature the samples were prepared. At higher concentrations, pure vaterite or a mixture of vaterite and calcite were present at the beginning of the experiment. After one day, pure vaterite was found in the samples that were prepared at 15 and 25 °C. If calcium carbonate precipitated at 50 °C, the XRD results showed a mixture of calcite and vaterite regardless of the time at which the sample was taken. The morphology of calcium carbonate particles prepared at various conditions changed from calcite cubes to spherical particles of vaterite and aragonite needles. When a low starting concentration was used, the morphology at the initial stage was strongly affected by the temperature at which the experiments were conducted. However, after one day only, cubes were present in all cases at low initial concentrations. In contrast, at high concentrations spherical particles precipitated at all three temperatures at the beginning of the reaction. Spherical particles were made up from smaller particles. Over time, the size of the particles was diminishing due to their disintegration into

  3. Développement et validation de méthodes HPLC-MS/MS et GC/MS-MS permettant le dosage des pesticides contenus dans les POCIS et les sédiments : application aux échantillons prélevés dans les principaux tributaires du bassin d'Arcachon

    OpenAIRE

    Desgranges, N.

    2010-01-01

    These last years, several surveys were conducted by different organizations, giving an indication of the overall state and quality of freshwaters. Among all the parameters considered, water pollution by pesticides is one of the most important part. Agricultural uses and environmental standards about pesticides are always evolving. Consequently, it is necessary to have a wider panel of molecules and lower limits of quantification. During this study, our aim was on one hand to widen the number ...

  4. 40 CFR 158.2010 - Biochemical pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides data...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2010 Biochemical pesticides... required to support registration of biochemical pesticides. Sections 158.2080 through 158.2084 identify...

  5. 40 CFR 158.2110 - Microbial pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides data requirements...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2110 Microbial pesticides data requirements. (a) For all microbial pesticides. (1) The following § 158.2120 through §...

  6. 40 CFR 152.175 - Pesticides classified for restricted use.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticides classified for restricted...) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Classification of Pesticides § 152.175 Pesticides classified for restricted use. The following uses of pesticide products containing...

  7. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  8. Long-term relationships among pesticide applications, mobility, and soil erosion in a vineyard watershed.

    Science.gov (United States)

    Sabatier, Pierre; Poulenard, Jérôme; Fanget, Bernard; Reyss, Jean-Louis; Develle, Anne-Lise; Wilhelm, Bruno; Ployon, Estelle; Pignol, Cécile; Naffrechoux, Emmanuel; Dorioz, Jean-Marcel; Montuelle, Bernard; Arnaud, Fabien

    2014-11-01

    Agricultural pesticide use has increased worldwide during the last several decades, but the long-term fate, storage, and transfer dynamics of pesticides in a changing environment are poorly understood. Many pesticides have been progressively banned, but in numerous cases, these molecules are stable and may persist in soils, sediments, and ice. Many studies have addressed the question of their possible remobilization as a result of global change. In this article, we present a retro-observation approach based on lake sediment records to monitor micropollutants and to evaluate the long-term succession and diffuse transfer of herbicides, fungicides, and insecticide treatments in a vineyard catchment in France. The sediment allows for a reliable reconstruction of past pesticide use through time, validated by the historical introduction, use, and banning of these organic and inorganic pesticides in local vineyards. Our results also revealed how changes in these practices affect storage conditions and, consequently, the pesticides' transfer dynamics. For example, the use of postemergence herbicides (glyphosate), which induce an increase in soil erosion, led to a release of a banned remnant pesticide (dichlorodiphenyltrichloroethane, DDT), which had been previously stored in vineyard soil, back into the environment. Management strategies of ecotoxicological risk would be well served by recognition of the diversity of compounds stored in various environmental sinks, such as agriculture soil, and their capability to become sources when environmental conditions change.

  9. Long-term relationships among pesticide applications, mobility, and soil erosion in a vineyard watershed

    Science.gov (United States)

    Sabatier, Pierre; Poulenard, Jérôme; Fanget, Bernard; Reyss, Jean-Louis; Develle, Anne-Lise; Wilhelm, Bruno; Ployon, Estelle; Pignol, Cécile; Naffrechoux, Emmanuel; Dorioz, Jean-Marcel; Montuelle, Bernard; Arnaud, Fabien

    2014-11-01

    Agricultural pesticide use has increased worldwide during the last several decades, but the long-term fate, storage, and transfer dynamics of pesticides in a changing environment are poorly understood. Many pesticides have been progressively banned, but in numerous cases, these molecules are stable and may persist in soils, sediments, and ice. Many studies have addressed the question of their possible remobilization as a result of global change. In this article, we present a retro-observation approach based on lake sediment records to monitor micropollutants and to evaluate the long-term succession and diffuse transfer of herbicides, fungicides, and insecticide treatments in a vineyard catchment in France. The sediment allows for a reliable reconstruction of past pesticide use through time, validated by the historical introduction, use, and banning of these organic and inorganic pesticides in local vineyards. Our results also revealed how changes in these practices affect storage conditions and, consequently, the pesticides' transfer dynamics. For example, the use of postemergence herbicides (glyphosate), which induce an increase in soil erosion, led to a release of a banned remnant pesticide (dichlorodiphenyltrichloroethane, DDT), which had been previously stored in vineyard soil, back into the environment. Management strategies of ecotoxicological risk would be well served by recognition of the diversity of compounds stored in various environmental sinks, such as agriculture soil, and their capability to become sources when environmental conditions change.

  10. Application of pesticide transport model for simulating diazinon runoff in California’s central valley

    Science.gov (United States)

    Joyce, Brian A.; Wallender, Wesley W.; Mailapalli, Damodhara R.

    2010-12-01

    Dormant spray application of pesticides to almond and other stone fruit orchards is the main source of diazinon during the winter in California's central valley. Understanding the pesticide transport and the tradeoffs associated with the various management practices is greatly facilitated by the use of physically-based contaminant transport models. In this study, performance of Joyce's et al. (2008) pesticide transport model was evaluated using experimental data collected from two ground treatments such as resident vegetation and bare soil. The model simulation results obtained in calibration and validation process were analyzed for pesticide concentration and total load. The pesticide transport model accurately predicted the pesticide concentrations and total load in the runoff from bare field and was capable of simulating chemical responses to rainfall-runoff events. In case of resident vegetation, the model results exhibited a larger range of variation than was observed in the bare soil simulations due to increased model parameterization with the addition of foliage and thatch compartments. Furthermore, the model was applied to study the effect of runoff lag time, extent of crop cover, organic content of soil and post-application irrigation on the pesticide peak concentration and total load. Based on the model results, recommendations were suggested to growers prior to implementing certain management decisions to mitigate diazinon transport in the orchard's spray runoff.

  11. Applicability of ELISA-based Determination of Pesticides for Groundwater Quality Monitoring

    Science.gov (United States)

    Tsuchihara, Takeo; Yoshimoto, Shuhei; Ishida, Satoshi; Imaizumi, Masayuki

    The principals and procedures of ELISA (Enzyme-linked Immunosorbent Assay)-based determination of pesticides (Fenitrothion) in environmental samples were reviewed, and the applicability of the ELISA method for groundwater quality monitoring were validated through the experimental tracer tests in soil columns and the field test in Okinoerabu Island. The test results showed that the ELISA method could be useful not only for screening but also for quantitative analysis of pesticides. In the experimental tracer tests in soil columns, the retardation of pesticides leaching compared with conservative tracers were observed. In the field test, the contamination of the pesticide was detected in groundwater samples in Okinoerabu Island, even though the targeted pesticide was considered to be applied to the upland field 4 months ago. In order to investigate the transport and fate of pesticides in groundwater taking into account retardation from the field to groundwater table and the residue in groundwater, continuous observations of pesticides in groundwater are in a strong need, and the ELISA method is applicable to the long-term quality groundwater monitoring.

  12. Resíduos de pesticidas em águas superficiais de área de nascente do Rio São Lourenço-MT: validação de método por extração em fase sólida e cromatografia líquida Pesticide residues in surface waters at the headwaters of São Lourenço River-MT, Brazil: validation of a method using solid-phase extraction and liquid chromatography

    Directory of Open Access Journals (Sweden)

    Anna Carolina Araújo Ribeiro

    2013-01-01

    Full Text Available A multiresidue method using HPLC/DAD for the determination of fourteen pesticides in water based on SPE, using SDVB (styrene divynilbenzene copolymer as adsorbent was validated. Recoveries from 61 to 120%, relative standard deviation between 2 and 15% and detection limits from 0.07 to 0.75 µg L-1 were obtained. It was applied to 66 surface water samples collected in a degraded area at the headwaters of São Lourenço river, Mato Grosso, Brazil. Eight pesticides were detected in concentrations ranging from 0.15 to 35.25 µg L-1. Considering ecotoxicological data, carbendazim and carbofuran may represent a risk to aquatic organisms. These results draw attention to the contamination of this vulnerable degraded area.

  13. Determination of Ethyl Carbamate in Alcoholic Beverages and Fermented Foods Sold in Korea

    Science.gov (United States)

    Ryu, Dayeon; Choi, Bogyoung; Kim, Eunjoo; Park, Seri; Paeng, Hwijin; Kim, Cho-il; Lee, Jee-yeon; Yoon, Hae Jung

    2015-01-01

    Ethyl carbamate (EC) classified as a probable human carcinogen (Group 2A) is naturally formed in alcoholic beverages and fermented foods during fermentation process and/or during storage. The objective of this study was to analyze EC in 34 food items including 14 alcoholic beverages and 20 fermented foods sold in Korea. Each food was collected from 18 supermarkets in 9 metropolitan cities in Korea, and then made into composite. According to food composition and alcohol content, samples were divided into four matrices such as apple juice, milk, Soju (liquor containing about 20% alcohol), and rice porridge. The maximum EC value of 151.06 µg/kg was found in Maesilju (liquor made from Maesil and Soju). Whisky and Bokbunjaju (Korean black raspberry wine) contained 9.90 µg/kg and 6.30 µg/kg, respectively. EC was not detected in other alcoholic beverages. Of 20 fermented foods, Japanese-style soy sauce had highest level of 15.59 µg/kg and traditional one contained 4.18 µg/kg. Soybean paste had 1.18 µg/kg, however, EC was not found in other fermented foods. PMID:26483888

  14. Cyanate as an Active Precursor of Ethyl Carbamate Formation in Sugar Cane Spirit.

    Science.gov (United States)

    Galinaro, Carlos A; Ohe, Thiago H K; da Silva, Augusto C H; da Silva, Sebastião C; Franco, Douglas W

    2015-08-26

    The thermodynamic and kinetic aspects of ethyl carbamate (EC) formation through the reaction between cyanate and ethanol were investigated. The rate constant values for cyanate ion decay and EC formation are (8.0 ± 0.4) × 10(-5) and (8.9 ± 0.4) × 10(-5) s(-1), respectively, at 25 °C in 48% aqueous ethanolic solution at pH 4.5. Under the investigated experimental conditions, the rate constants are independent of the ethanol and cyanate concentrations but increase as the temperature increases (ΔH1(⧧) = 19.4 ± 1 kcal/mol, ΔS1(⧧) = −12.1 ± 1 cal/K, and ΔG1(⧧) = 23.0 ± 1 kcal/mol) and decrease as the solution pH increases. According to molecular modeling (DFT) that was performed to analyze the reaction mechanism, the isocyanic acid (HNCO) is the active EC precursor. The calculated ΔG1(⧧), ΔH1(⧧), and ΔS1(⧧) values are in very good agreement with the experimental ones. PMID:26248556

  15. Vibrational spectra and normal coordinate analysis of 2-hydroxy-3-(2-methoxyphenoxy) propyl carbamate

    Science.gov (United States)

    Muthu, S.; Renuga, S.

    2014-11-01

    In this work, the vibrational spectral analysis was carried out by using FT-Raman and FTIR spectroscopy in the range 50-4000 cm-1 and 450-4000 cm-1 respectively, for 2-hydroxy-3-(2-methoxyphenoxy) propyl carbamate (2H3MPPLC) molecule. The molecular structure, fundamental vibrational frequencies and intensities of the vibrational bands were interpreted with the aid of structure optimizations and normal coordinate force field calculations based on density functional theory (DFT) and ab initio HF methods with 6-31G(d,p) basis set. The complete vibrational assignments of wave numbers were made on the basis of potential energy distribution (PED). The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The scaled B3LYP/6-31G(d,p) results show the best agreement with the experimental values over the other method. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results confirm the occurrence of intramolecular charge-transfer (ICT) within the molecule. The dipole moment (μ), polarizability (α) and hyperpolarizability (β) of the investigated molecule has been computed using B3LYP/6-31G(d,p) method. Mulliken population analysis on atomic charges was also calculated. Besides, frontier molecular orbitals, molecular electrostatic potential (MEP) and thermodynamic properties were performed.

  16. Identification of Novel Steroidal Androgen Receptor Degrading Agents Inspired by Galeterone 3β-Imidazole Carbamate.

    Science.gov (United States)

    Purushottamachar, Puranik; Kwegyir-Afful, Andrew K; Martin, Marlena S; Ramamurthy, Vidya P; Ramalingam, Senthilmurugan; Njar, Vincent C O

    2016-07-14

    Degradation of all forms of androgen receptors (ARs) is emerging as an advantageous therapeutic paradigm for the effective treatment of prostate cancer. In continuation of our program to identify and develop improved efficacious novel small-molecule agents designed to disrupt AR signaling through enhanced AR degradation, we have designed, synthesized, and evaluated novel C-3 modified analogues of our phase 3 clinical agent, galeterone (5). Concerns of potential in vivo stability of our recently discovered more efficacious galeterone 3β-imidazole carbamate (6) led to the design and synthesis of new steroidal compounds. Two of the 11 compounds, 3β-pyridyl ether (8) and 3β-imidazole (17) with antiproliferative GI50 values of 3.24 and 2.54 μM against CWR22Rv1 prostate cancer cell, are 2.75- and 3.5-fold superior to 5. In addition, compounds 8 and 17 possess improved (∼4-fold) AR-V7 degrading activities. Importantly, these two compounds are expected to be metabolically stable, making them suitable for further development as new therapeutics against all forms of prostate cancer. PMID:27437082

  17. [Degradation of urea and ethyl carbamate in Chinese Rice wine by recombinant acid urease].

    Science.gov (United States)

    Zhou, Jianli; Kang, Zhen; Liu, Qingtao; Du, Guocheng; Chen, Jian

    2016-01-01

    Ethyl carbamate (EC) as a potential carcinogen commonly exists in traditional fermented foods. It is important eliminate urea that is the precursors of EC in many fermented foods, including Chinese Rice wine. On the basis of achieving high-level overexpression of food-grade ethanol-resistant acid urease, we studied the hydrolysis of urea and EC with the recombinant acid urease. Recombinant acid urease showed degraded urea in both the simulated system with ethanol and Chinese Rice wine (60 mg/L of urea was completely degraded within 25 h), indicating that the recombinant enzyme is suitable for the elimination of urea in Chinese Rice wine. Although recombinant acid urease also has degradation catalytic activity on EC, no obvious degradation of EC was observed. Further investigation results showed that the Km value for urea and EC of the recombinant acid urease was 0.7147 mmol/L and 41.32 mmol/L, respectively. The results provided theoretical foundation for realizing simultaneous degradation of urea and EC.

  18. Reduced production of ethyl carbamate for wine fermentation by deleting CAR1 in Saccharomyces cerevisiae.

    Science.gov (United States)

    Guo, Xue-Wu; Li, Yuan-Zi; Guo, Jian; Wang, Qing; Huang, Shi-Yong; Chen, Ye-Fu; Du, Li-Ping; Xiao, Dong-Guang

    2016-05-01

    Ethyl carbamate (EC), a pluripotent carcinogen, is mainly formed by a spontaneous chemical reaction of ethanol with urea in wine. The arginine, one of the major amino acids in grape musts, is metabolized by arginase (encoded by CAR1) to ornithine and urea. To reduce the production of urea and EC, an arginase-deficient recombinant strain YZ22 (Δcarl/Δcarl) was constructed from a diploid wine yeast, WY1, by successive deletion of two CAR1 alleles to block the pathway of urea production. The RT-qPCR results indicated that the YZ22 almost did not express CAR1 gene and the specific arginase activity of strain YZ22 was 12.64 times lower than that of parent strain WY1. The fermentation results showed that the content of urea and EC in wine decreased by 77.89 and 73.78 %, respectively. Furthermore, EC was forming in a much lower speed with the lower urea during wine storage. Moreover, the two CAR1 allele deletion strain YZ22 was substantially equivalent to parental strain in terms of growth and fermentation characteristics. Our research also suggested that EC in wine originates mainly from urea that is produced by the arginine. PMID:26831650

  19. 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)

  20. Organochlorine Pesticides in the Environment

    Science.gov (United States)

    Stickel, L.F.

    1968-01-01

    Each year for nearly 20 years, thousands of pounds of persistent organochlorine pesticides have been applied to outdoor areas in many countries. These compounds may last for a very long time in the environment, and be carried by wind, water, and animals to places far distant from where they are used. As a result, most living organisms now contain organochlorine residues. This paper constitutes a selective review of the literature concerning the occurrence, distribution, and effects of organochlorines in the environment. Highest concentrations generally occur in carnivorous species. Thus predatory and fish-eating birds ordinarily have higher residues than do herbivores; quantities are similar in birds of similar habits in different countries. Any segment of the ecosystem - marshland, pond, forest, or field - receives various amounts and kinds of pesticides at irregular intervals. The different animals absorb, detoxify, store, and excrete pesticides at different rates. Different degrees of magnification of pesticide residues by living organisms in an environment are the practical result of many interactions that are far more complex than implied by the statement of magnification up the food chain. These magnifications may be millions of times from water to mud or only a few times from food to first consumer. Direct mortality of wild animals as an aftermath of recommended pesticide treatments has been recorded in the literature of numerous countries. However, accidents and carelessness also accompany pesticide use on a percentage basis and are a part of the problem. More subtle effects on the size and species composition of populations are more difficult to perceive in time to effect remedies. The possibility of ecological effects being mediated through changes in physiology and behavior has received some attention and has resulted in some disquieting findings. These include discovery of the activity of organochlorines in stimulating the breakdown of hormones or in

  1. 77 FR 23713 - Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for...

    Science.gov (United States)

    2012-04-20

    ... relationship between EPA-approved labels for pesticides registered under the Federal Insecticide, Fungicide... AGENCY Pesticides; Final Guidance on Material Safety Data Sheets as Pesticide Labeling; Request for.... SUMMARY: The Agency is announcing the availability of a Pesticide Registration Notice (PR Notice)...

  2. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  3. Pesticide risks around the home (image)

    Science.gov (United States)

    Pesticides are substances which kill or deter unwanted pests, such as insects or rodents. These substances can ... avoid an accidental ingestion is to keep all pesticides out of the reach of children.

  4. 76 FR 10026 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2011-02-23

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide... the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as amended. EPA is publishing...

  5. Neurobehavioral and neurodevelopmental effects of pesticide exposures

    DEFF Research Database (Denmark)

    London, Leslie; Beseler, Cheryl; Bouchard, Maryse F;

    2012-01-01

    The association between pesticide exposure and neurobehavioral and neurodevelopmental effects is an area of increasing concern. This symposium brought together participants to explore the neurotoxic effects of pesticides across the lifespan. Endpoints examined included neurobehavioral, affective ...

  6. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  7. 75 FR 5077 - Pesticide Product; Registration Application

    Science.gov (United States)

    2010-02-01

    ... Pollution Prevention Division (7511P), Office of Pesticide Programs, Environmental Protection Agency, 1200... the FDA as a stabilizer in polymers used in producing, manufacturing, packaging, processing, and... Pollution Prevention Division, Office of Pesticide Programs. BILLING CODE 6560-50-S...

  8. Monitoring of pesticide residue in bovine milk from Nadia district, West Bengal.

    Science.gov (United States)

    Singh, Aruna Kumari; Sar, Tapas Kumar; Mandal, Tapan Kumar

    2013-07-01

    Monitoring of 210 bovine milk samples collected from local markets in the Nadia district of West Bengal during 2011 was performed. Samples were collected in summer and winter seasons. Analysis of pesticides was performed by using a multiresidue method validated in the laboratory. The quantification was performed using GC-ECD. Analysis revealed the presence of lindane in less than 1 % of milk samples. Endosulfan I and II were also detected and were found to exceed MRL recommended by Codex. Overall 1.90 % of the analyzed samples showed trace to measurable amount of pesticide residues. The monitored area provided pesticide residues data of milk, assisting in future scientific assessment on pesticide usage. PMID:23708263

  9. UNWANTED AGRICULTURAL PESTICIDES: STATE DISPOSAL SYSTEMS

    OpenAIRE

    Centner, Terence J.

    1997-01-01

    Millions of pounds of unwanted pesticides have accumulated in barns throughout our country. The potential environmental and health risks posed by this situation has garnered public attention and governmental action. The federal government has revised its Universal Waste Rule so that it is easier to dispose of unwanted pesticides rather than simply banned pesticides. Nearly every state has initiated efforts to collect and dispose of accumulated pesticides in a safe manner. While the possession...

  10. Geostatistics as a basis to the CMLS pesticide simulation model with validation in soil columns Geoestatística como suporte ao modelo de simulação de agrotóxico CMLS com validação em colunas de solos

    Directory of Open Access Journals (Sweden)

    Gilberto Nicolella

    2005-01-01

    Full Text Available The use of simulation models is probably the most efficient means for predicting the behavior of pesticides in the soil-plant-water system. The CMLS (Chemical Movement in Layered Soils simulation model for predicting the fate of pesticides was used for studying the behavior of tebuthiuron, a herbicide used in sugar cane crops, from a sampling grid with 111 sampling points 200 m apart from one another and encompassing three types of soil: Ustic Quartzipsamment, Rhodic Hapludox and Typic Hapludox, all with medium and clay textures. The 373 points assessed by the simulator, generated from samples coming from the original grid and through the geostatistical methods of variography and ordinary kriging, returned the depth values reached by the herbicide after six years of simulation (1989-1995. For the Ustic Quartzipsamment, tebuthiuron, in four simulated points, returned depth values above 43 m and a maximum 50 m, with a certain amount of the product still remaining in the soil that was close to 10% of the original 1.1 kg ha-1 applied. Results from the column assay used for validating the model showed that the model overestimated the depth reached by the herbicide in 6.6% as compared to the column value for the Ustic Quartzipsamment. The depth was underestimated in 4.5% and 20% for the Typic Hapludox and the Rhodic Hapludox, respectively. These data support the adequacy of the model for assessing the fate of tebuthiuron in both Ustic Quartzipsamment and Typic Hapludox.O uso de modelos de simulação é provavelmente a maneira mais eficiente para predizer o comportamento de agrotóxicos no sistema solo/água/planta. O modelo de simulação de destino de agrotóxicos CMLS (Chemical Movement in Layered Soils, foi usado para estudar o comportamento do herbicida tebuthiuron, utilizado na cultura de cana-de-açúcar, a partir de uma grade de amostragem composta de 111 pontos amostrais, equi-espaçados de 200 m e englobando três tipos de solo: Neossolo

  11. Pesticides: Food and environmental implications

    International Nuclear Information System (INIS)

    Pesticides are an integral part of modern agriculture, also in most developing countries. Although the annual average consumption of active ingredients in agriculture may be below 0.1 kg a.i./ha, most countries now consume more than 2 kg a.i./ha; some of the intensively cropped regions in South-East Asia are exposed to even higher amounts. Inherent contamination of the environment follows if rules and regulations are not strictly adhered to. The search for safer, less persistent and more specific pesticides and examination of the fate of applied pesticides in various regions of the world were the main themes of the symposium. Special emphasis was placed on the use of nuclear techniques, especially on labelled compounds in research. The Proceedings include all the papers and posters that were presented. Refs, figs and tabs

  12. 75 FR 76463 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-12-08

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide....regulations.gov . Follow the on-line instructions for submitting comments. Mail: Office of Pesticide...

  13. Pesticide use in Vietnamese vegetable production

    NARCIS (Netherlands)

    Hoi, P.V.; Mol, A.P.J.; Oosterveer, Peter; Brink, van den P.J.; Huong, P.T.M.

    2016-01-01

    Vietnam has had varying success over the past decade with its pesticides policy. Some of the most toxic pesticides have been banned from the market. But while many countries have successfully decreased agricultural pesticide use per hectare, this has not (yet) happened in Vietnam. Due to insuffic

  14. Pesticides in Schools: Reducing the Risks.

    Science.gov (United States)

    New York State Office of the Attorney General, Albany.

    This report presents findings of state-wide use of pesticides in New York public schools along with a description of the survey, information about the potential dangers of these chemicals, and the steps schools and communities can take to minimize pesticide use. Findings show that 87 percent of New York's schools use pesticides that contain…

  15. 75 FR 24695 - Pesticide Products; Registration Applications

    Science.gov (United States)

    2010-05-05

    ... AGENCY Pesticide Products; Registration Applications AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: This notice announces receipt of applications to register new uses for pesticide....regulations.gov . Follow the on-line instructions for submitting comments. Mail: Office of Pesticide...

  16. Pesticide risk indicators for surface water and their validation

    OpenAIRE

    Bockstaller, Christian; Wohlfahrt, Julie; Hubert, A.; Keichinger, Olivier; Girardin, Philippe

    2007-01-01

    La mise en place de solutions au problème de pollution par les produits phytosanitaires nécessite des outils d’évaluation des risques liés à l’application des ces susbstances. Après avoir brièvement revus différents groupes d’indicateurs, nous présentons le module eau de surface de l’indicateur I-Phy développé à l’INRA de Colmar dans le cadre de la méthode INDIGO®. Le mode de construction repose sur des régles de décision associant la logique floue. Dans le module eau de surface, les variable...

  17. Ethyl-bridged hybrid column as an efficient alternative for HPLC analysis of plasma amino acids by pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate.

    Science.gov (United States)

    Castellanos, Mar; Van Eendenburg, Cecile Van; Gubern, Carme; Sanchez, Juan M

    2016-09-01

    Conventional C18 silica columns have proven to be useful for the analysis of amino acids (AA) from protein hydrolysates but undesirable peak overlapping is usually found when analyzing body fluids given that a large number of AAs are present in the samples. As an alternative to silica packings, an ethyl-bridged packing for reversed-phase liquid chromatography of derivatized AAs with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) has been evaluated. The new packing material improves the separation efficiency allowing better separations when analyzing biological fluids. Moreover, this packing has advantages for routine AA analysis, such as a decrease in the total running time and an increase in the life-time of the columns. The pH of the mobile phase has a significant effect on the elution behavior of the AQC hydrolysis product (AMQ) and on the AA derivatives. It is not possible to elute AMQ before detecting the first AA derivative, which requires an accurate adjustment of the pH in the range of 5.30-5.35 to obtain good separation and resolution for the most polar compounds. Under the conditions proposed, it is possible to separate all AAs except the Gly-Gln pair, which is not a problem when hydrolyzed samples are analyzed. The AMQ-Ser pair requires either the use of a different mobile phase pH for its baseline separation or the use of fluorescence detection. Two different procedures for protein removal from plasma samples have been evaluated, solvent precipitation and ultrafiltration (UF) and it has been found that UF gives better results as no significant losses of AAs were observed. The validation of the proposed method with UV detection gives method detection limits in the range of 8-12μM, with repeatability values<8% (n=6) and inter-day precision in plasma samples ranging from 4 to 13% (n=4). PMID:27428457

  18. Ethyl-bridged hybrid column as an efficient alternative for HPLC analysis of plasma amino acids by pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate.

    Science.gov (United States)

    Castellanos, Mar; Van Eendenburg, Cecile Van; Gubern, Carme; Sanchez, Juan M

    2016-09-01

    Conventional C18 silica columns have proven to be useful for the analysis of amino acids (AA) from protein hydrolysates but undesirable peak overlapping is usually found when analyzing body fluids given that a large number of AAs are present in the samples. As an alternative to silica packings, an ethyl-bridged packing for reversed-phase liquid chromatography of derivatized AAs with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) has been evaluated. The new packing material improves the separation efficiency allowing better separations when analyzing biological fluids. Moreover, this packing has advantages for routine AA analysis, such as a decrease in the total running time and an increase in the life-time of the columns. The pH of the mobile phase has a significant effect on the elution behavior of the AQC hydrolysis product (AMQ) and on the AA derivatives. It is not possible to elute AMQ before detecting the first AA derivative, which requires an accurate adjustment of the pH in the range of 5.30-5.35 to obtain good separation and resolution for the most polar compounds. Under the conditions proposed, it is possible to separate all AAs except the Gly-Gln pair, which is not a problem when hydrolyzed samples are analyzed. The AMQ-Ser pair requires either the use of a different mobile phase pH for its baseline separation or the use of fluorescence detection. Two different procedures for protein removal from plasma samples have been evaluated, solvent precipitation and ultrafiltration (UF) and it has been found that UF gives better results as no significant losses of AAs were observed. The validation of the proposed method with UV detection gives method detection limits in the range of 8-12μM, with repeatability values<8% (n=6) and inter-day precision in plasma samples ranging from 4 to 13% (n=4).

  19. Determination of organophosphorus pesticide residues in tomatoes by gas chromatography

    International Nuclear Information System (INIS)

    Chloropyriphos and malathion are two organophosphorus pesticides from many others pesticides widely used by famers in agriculture .Because of their bad effect on human health, officials standards are set by the international organisations and communities to ensure safer food for consumer .In the same way, scientists over the world are working hard to develop new detection techniques responding to the international requirements. In this study, an ' IAEA-ethylacetate method ', an adaptation of the popular QuEChERS multi residue method, was optimized to analyse chloropyriphos and Malathion residues in tomatoes .Ethyl-Acetate was used as an extraction solvent the PSA was kept for the clean up procedure. GC-NPD is used for samples analysis .The method optimized is specifique, selective with a recovery averaged more than 70 pour cent. A complete validation of the method is necessary to be used for routine analysis.

  20. 茶树油清除豇豆农药残留的效果%Effects of tea tree oils on removing pesticide residue in cowpea

    Institute of Scientific and Technical Information of China (English)

    林丽静; 程盛华; 李积华; 黄茂芳; 唐永富; 朱德明

    2013-01-01

    Pesticides are widely used as an insurance policy against devastating crop losses from pests and diseases. Excessive usage of pesticides may lead to contamination of the crop and the environment, eventually posing a risk of pesticide-related illnesses to humans. Previous literature has shown that water washing is only partially effective in removing pesticides, and in the case of liposoluble pesticides, a cosolvent must be used as an adjuvant. Recently, naturally occurring adjuvants are gaining prominence over synthetic chemical compounds. Tea tree oil (TTO, the oil of Melaleuca alternifolia), a natural, volatile essential oil, is mainly extracted by steam distillation from the fresh leaves and terminal branchlets of the plant. It has attracted significant interest due to its antifungal, antiviral, and antibacterial bioactivities. However, to the best of our knowledge, there are fewer experimental data evaluating its efficacy in the removal of pesticide residues. In this study, the effects of TTO on removing pesticide residue were carried out in the cowpea. Volume:volume (v:v) concentrations of 0.05%, 0.1%, 0.2%, 0.4% and 0.8% of TTO and water soluble tea tree oil (WTTO) in water were used to remove a standardized pesticide mixture (organophosphorus, pyrethroid, and carbamate compounds) from cowpeas. Sample pretreatment (pesticide application to cowpeas) was performed according to agricultural industry standards. The objective pesticide residues in cowpeas were assayed by gas chromatography (GC) and chromatography-mass spectrometry detection (GC-MS), and then the clearance rate was calculated. The results showed that TTO was able to remove the three kinds of pesticides from cowpeas. Moreover, the removal efficiency increased with increasing concentration of TTO. The effect of clearing organophosphate was much more obvious than that of either pyrethroid or carbamate. It was suggested that small liposoluble molecules of TTO rapidly infiltrate the cowpea surface to

  1. Tandem Mass Spectrometry Measurement of the Collision Products of Carbamate Anions Derived from CO2 Capture Sorbents: Paving the Way for Accurate Quantitation

    Science.gov (United States)

    Jackson, Phil; Fisher, Keith J.; Attalla, Moetaz Ibrahim

    2011-08-01

    The reaction between CO2 and aqueous amines to produce a charged carbamate product plays a crucial role in post-combustion capture chemistry when primary and secondary amines are used. In this paper, we report the low energy negative-ion CID results for several anionic carbamates derived from primary and secondary amines commonly used as post-combustion capture solvents. The study was performed using the modern equivalent of a triple quadrupole instrument equipped with a T-wave collision cell. Deuterium labeling of 2-aminoethanol (1,1,2,2,-d4-2-aminoethanol) and computations at the M06-2X/6-311++G(d,p) level were used to confirm the identity of the fragmentation products for 2-hydroxyethylcarbamate (derived from 2-aminoethanol), in particular the ions CN-, NCO- and facile neutral losses of CO2 and water; there is precedent for the latter in condensed phase isocyanate chemistry. The fragmentations of 2-hydroxyethylcarbamate were generalized for carbamate anions derived from other capture amines, including ethylenediamine, diethanolamine, and piperazine. We also report unequivocal evidence for the existence of carbamate anions derived from sterically hindered amines ( Tris(2-hydroxymethyl)aminomethane and 2-methyl-2-aminopropanol). For the suite of carbamates investigated, diagnostic losses include the decarboxylation product (-CO2, 44 mass units), loss of 46 mass units and the fragments NCO- ( m/z 42) and CN- ( m/z 26). We also report low energy CID results for the dicarbamate dianion (-O2CNHC2H4NHCO{2/-}) commonly encountered in CO2 capture solution utilizing ethylenediamine. Finally, we demonstrate a promising ion chromatography-MS based procedure for the separation and quantitation of aqueous anionic carbamates, which is based on the reported CID findings. The availability of accurate quantitation methods for ionic CO2 capture products could lead to dynamic operational tuning of CO2 capture-plants and, thus, cost-savings via real-time manipulation of solvent

  2. Pesticide residues in Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) from Southern Lake Victoria, Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Henry, L. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania); Kishimba, M.A. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania)]. E-mail: kishimba@chem.udsm.ac.tz

    2006-03-15

    Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) samples were collected from fish landing stations in nine riparian districts on the Tanzanian side of Lake Victoria and screened for residues of 64 organochlorine, organophosphorus, carbamate, and pyrethroid pesticides. The residue levels in the fish fillet were up to 0.003, 0.03 and 0.2 mg/kg fresh weight (0.7, 3.8 and 42 mg/kg lipid weight) of fenitrothion, DDT and endosulfan, respectively. Mean levels within sites were up to 0.002, 0.02 and 0.1 mg/kg fresh weight (0.5, 0.5 and 16 mg/kg lipid weight), respectively. The detection of higher levels of p,p'-DDT than the degradation products (p,p'-DDD and p,p'-DDE), and higher levels of endosulfan isomers ({alpha} and {beta}) than the sulphate, in fish samples, implied recent exposure of fish to DDT and endosulfan, respectively. Generally, most of the fish samples had residue levels above the average method detection limits (MDLs), but were within the calculated ADI. - Fish from Lake Victoria had relatively low pesticide levels.

  3. Vibrational spectra study of phosphorus dendrimer containing azobenzene, ammonium and carbamate groups

    Science.gov (United States)

    Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2013-06-01

    The FTIR and FT Raman spectra of the first generation dendrimers, possessing carbamate (G1) or ammonium (G2) terminal groups were studied. The structural optimization and normal mode analysis were performed for dendrimers on the basis of the density functional theory (DFT). These calculations of G2 gave the frequencies of vibrations, infrared intensities and Raman scattering activities for the E- and Z-forms of azobenzene unit. The energy difference between the E- and Z-forms of G2 is 27.36 kcal/mol. The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendrimers molecules have a concave lens structure with planar -O-C6H4-CHdbnd N-N(CH3)Pdbnd S, and -O-C6H4-Ndbnd N-C6H4-CHdbnd N-NH-Cdbnd O-CH2-N fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of dendrimers G1 and G2 were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The strong band 1605 cm-1 in the IR spectra show marked changes of the optical density in dependence of substituents in the aromatic ring. The differences in the IR and Raman spectra of G2 for the E- and Z-forms of azobenzene units were cleared up. During structural isomerization of azobenzene units, redistribution of band intensities appears to a much higher extent than frequency shifts.

  4. Detection of Methomyl, a Carbamate Insecticide, in Food Matrices Using Terahertz Time-Domain Spectroscopy

    Science.gov (United States)

    Baek, Seung Hyun; Kang, Ju Hee; Hwang, Yeun Hee; Ok, Kang Min; Kwak, Kyungwon; Chun, Hyang Sook

    2016-05-01

    The aim of this study was to investigate the feasibility of detecting methomyl, a carbamate insecticide, in food matrices (wheat and rice flours) using terahertz time-domain spectroscopy (THz-TDS). In the frequency range 0.1-3 THz, the characteristic THz absorption peaks of methomyl at room temperature were detected at 1 (33.4 cm-1), 1.64 (54.7 cm-1), and 1.89 (63.0 cm-1) THz. For detailed spectral analysis, the vibrational frequency and intensity of methomyl were calculated using solid-state density functional theory to mimic molecular interactions in the solid state. Qualitatively, the simulated spectrum was in good agreement with the experimental spectrum. Analysis of the individual absorption modes revealed that all of the features in the THz spectrum of methomyl were mainly generated from intermolecular vibrations. The peak appearing at 1 THz (33.4 cm-1) was then selected and tested for its suitability as a fingerprint for detecting methomyl in food matrices. Its absorbance was dose-dependently distinguishable from that of wheat and rice flours. The calibration curve of methomyl had a regression coefficient of >0.974 and a detection limit of <3.74 %. Accuracy and precision expressed as recovery and relative standard deviation in interday repeatability were in the ranges 78.0-96.5 and 2.83-4.98 %, respectively. Our results suggest that THz-TDS can be used for the rapid detection of methomyl in foods, but its sensitivity needs to be improved.

  5. 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.

  6. In situ exposure history modulates the molecular responses to carbamate fungicide Tattoo in bivalve mollusk.

    Science.gov (United States)

    Falfushynska, Halina I; Gnatyshyna, Lesya L; Stoliar, Oksana B

    2013-04-01

    The aim of the present study was the investigation of the effect of in situ exposure history on the responses of freshwater mussels to thiocarbamate fungicide. Male bivalve mollusks Anodonta anatina (Unionidae) from polluted (A) and unpolluted (F) sites were subjected to 14 days of exposure to fungicide Tattoo (mixture of propamocarb and mancozeb, 91 μg L(-1)). When unexposed mussels were compared, chronic effect of toxic environment in site A was confirmed by oxidative stress indices (high levels of superoxide dismutase and catalase activities, lipid peroxidation, protein carbonyls and oxyradical production, low level of total glutathione (GSH)), genotoxicity (high levels of DNA-strand breaks and caspase-3 activity in digestive gland), and cytotoxicity (low lysosomal membrane stability in hemocytes), elevated vitellogenin-like proteins (Vtg-LP) concentration in gonads, high levels of Cu, Zn, Cd, metallothionein (MT)-bound metals (MT-Me) and MT-related thiol (MT-SH), and low ethoxyresorufin-O-deethylase (EROD) activity in digestive gland. The major differences in the responses of the two exposed groups were related to antioxidant defense and MT: in the group A, prominent oxidative stress response with the participation of MT-SH and GSH in the gills, EROD activation, but decrease of MT-Me level was shown, whereas in group F exposure provoked the elevation of MT-Me, caspase-3 and Vtg-LP values. Carbamate did not cause cholinesterase depletion and cytotoxicity. However, genotoxic and pro-oxidant effects (increased levels of hemocytes with micronuclei and nuclear abnormalities, DNA-strand breaks and oxyradical in digestive gland), were common responses for both the exposed groups. PMID:23306937

  7. Validação de método para determinação de resíduos de agrotóxicos em tomate: uma experiência laboratorial Method validation for determination of pesticide residues in tomatoes: a laboratorial experience

    Directory of Open Access Journals (Sweden)

    Maria Helena Wohlers Morelli Cardoso

    2010-05-01

    Full Text Available Um modelo de procedimento para validação de método de ensaio para determinação de cinco agrotóxicos (γ - HCH, clorotalonil, fenitrotiona, clorpirifós e procimidona em matriz tomate é demonstrado através da análise cromatográfica. A amostra processada é extraída com 30 mL de acetona e em seguida com 60 mL de uma mistura diclometano: éter de petróleo (1:1. O volume total é centrifugado e a alíquota orgânica é filtrada sob Na2SO4. Um mililitro de extrato orgânico é concentrado e dissolvido em um mililitro de iso-octano. Um microlitro do extrato é analisado no cromatógrafo a gás com detector por captura de elétrons - CG/DCE. Foram avaliados seletividade, linearidade, repetitividade, recuperação e limites de detecção e de quantificação. As recuperações obtidas variaram de 70 a 110%, considerando-se os níveis de adição de agrotóxicos/amostra de 0,02 a 2,50 mg.kg-1. Os limites de detecção do método variaram de 0,004 a 0,006 mg.kg-1 e os de quantificação entre 0,014 e 0,020 mg.kg-1.A validation procedure model of a multiresidue method is presented for chromatographic analyses of five pesticides residues γ-HCH, chlorothalonil, fenitrothion, chlorpyrifos and procymidone applied on tomatoes. The tomatoes were processed and extracted by acetone plus a mixture of dichloromethane:petroleum benzine (1:1. The volume was centrifuged and was then filtered under Na2SO4. One milliliter of organic extract was concentrated then diluted in isooctane and one microliter was analyzed in the gas chromatograph with electron capture detector - GC/ECD. The parameters evaluated were selectivity, linearity, repeatability, recovery, and limits of detection and quantification. The recovery ranged from 70 to 110% in the concentration range of 0.02 to 2.50 mg.kg-1. The limits of detection ranged from 0.004 to 0.006 mg.kg-1 and the limits of quantification were between 0.014 to 0.02 mg.kg-1.

  8. Linear and nonlinear models for predicting fish bioconcentration factors for pesticides.

    Science.gov (United States)

    Yuan, Jintao; Xie, Chun; Zhang, Ting; Sun, Jinfang; Yuan, Xuejie; Yu, Shuling; Zhang, Yingbiao; Cao, Yunyuan; Yu, Xingchen; Yang, Xuan; Yao, Wu

    2016-08-01

    This work is devoted to the applications of the multiple linear regression (MLR), multilayer perceptron neural network (MLP NN) and projection pursuit regression (PPR) to quantitative structure-property relationship analysis of bioconcentration factors (BCFs) of pesticides tested on Bluegill (Lepomis macrochirus). Molecular descriptors of a total of 107 pesticides were calculated with the DRAGON Software and selected by inverse enhanced replacement method. Based on the selected DRAGON descriptors, a linear model was built by MLR, nonlinear models were developed using MLP NN and PPR. The robustness of the obtained models was assessed by cross-validation and external validation using test set. Outliers were also examined and deleted to improve predictive power. Comparative results revealed that PPR achieved the most accurate predictions. This study offers useful models and information for BCF prediction, risk assessment, and pesticide formulation. PMID:27183335

  9. Pesticide mass budget in a stormwater wetland.

    Science.gov (United States)

    Maillard, Elodie; Imfeld, Gwenaël

    2014-01-01

    Wetlands are reactive landscape zones that provide ecosystem services, including the improvement of water quality. Field studies distinguishing pesticide degradation from retention to evaluate the sink and source functions of wetlands are scarce. This study evaluated based on a complete mass budget the partitioning, retention, and degradation of 12 pesticides in water, suspended solids, sediments, and organisms in a wetland receiving contaminated runoff. The mass budget showed the following: (i) dissolved pesticides accounted for 95% of the total load entering the wetland and the pesticide partitioning between the dissolved phase and the suspended solids varied according to the molecules, (ii) pesticides accumulated primarily in the dithiocarbamates were degraded under oxic conditions in spring, whereas glyphosate and aminomethylphosphonic acid (AMPA) degradation occurred under reducing conditions during the summer. The complete pesticide mass budget indicates the versatility of the pesticide sink and source functions of wetland systems. PMID:25003558

  10. Synthesis and antimicrobial activities of new oxime carbamates of 3-aryl-2-thioquinazolin-4(3H)-one

    Indian Academy of Sciences (India)

    Suresh S Patil; Swati D Jadhav; M B Deshmukh

    2012-09-01

    S-alkylation of 3-aryl-2-thioquinazolin-4(3H)-one (1) with chloroacetone gave 2-(propanonyl thio)-3-arylquinazol-4(3H)ones (2). Further, the treatment of compound (2) with hydroxylamine hydrochloride gave the corresponding oximes (3) which on reaction with phenyl isocyanate in THF yielded corresponding oxime carbamates 4. The synthesized compounds have been confirmed using IR and 1H NMR, mass spectral data together with elemental analysis. All newly synthesized compounds have been tested for their antibacterial and antifungal activities.

  11. Onsager heat of transport of carbon dioxide at the surface of aqueous ammonia: The remarkable effect of carbamate formation

    Science.gov (United States)

    Packwood, Daniel M.; Phillips, Leon F.

    2010-11-01

    The Onsager heat of transport Q∗ has been measured for CO 2 at the surface of aqueous ammonia. The heat of transport incorporates the enthalpy of reaction of gaseous CO 2 with ammonia, adsorbed on the liquid surface, to form adsorbed ammonium carbamate, with the result that -Q∗ has the unusually large value of 180 kJ mol -1. Measurement of Q∗ for transfer of a reactive species through a surfactant monolayer is proposed as a new method of studying reactions at liquid and quasi-liquid surfaces.

  12. 酒中氨基甲酸乙酯的研究%Research Advancement of Ethyl Carbamate in Liquor

    Institute of Scientific and Technical Information of China (English)

    张瑞雨; 梁孟军; 李旭

    2014-01-01

    The mechanism,jeopardy,analysis method of ethyl carbamate(EC) was summarized as a carcinogen for public health.The limitation standard of EC was proposed to be established.%本文对酒中氨基甲酸乙酯的形成机制、危害、检测方法进行了综述,引起社会对这种致癌物质的认识和关注,倡导建立氨基甲酸乙酯的限量标准。

  13. tert-Butyl N-[6-(N,N-dipropylcarbamoyl-1,3-benzothiazol-2-yl]carbamate

    Directory of Open Access Journals (Sweden)

    Xin Fang

    2010-05-01

    Full Text Available The title compound C19H27N3O3S, crystallizes with two unique molecules in the asymmetric unit. The benzene ring of each benzothiazole unit carries a dipropylcarbamoyl substituent in the 6-position and a tert-butyl carbamate unit on each thiazole ring. In the crystal structure, intermolecular N—H...N and weak C—H...O hydrogen bonds form centrosymmetric dimers. Additional C—H...O contacts construct a three-dimensional network. A very weak C—H...π contact is also present.

  14. tert-Butyl N-[2-(N-isobutyl-4-meth-oxy-benzene-sulfonamido)-eth-yl]carbamate.

    Science.gov (United States)

    Bai, Xiao-Guang; Wang, Ju-Xian

    2014-06-01

    The title compound, C18H30N2O5S, was synthesized by the reaction of tert-butyl 2-(iso-butyl-amino)-ethyl-carbamate with p-meth-oxy-phenyl-sulfonyl chloride. In the mol-ecule, two intra-molecular C-H⋯O hydrogen bonds are observed. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds involving the imino group N atom and the ester group O atom into chains running parallel to the b axis. The chains are further connected by C-H⋯O hydrogen bonds, forming layers parallel to the bc plane. PMID:24940254

  15. Pesticides, People, and the Environment

    Science.gov (United States)

    Miller, Roxanne Greitz

    2005-01-01

    If a teacher were to ask his/her students what they do when they find ants or other insects in their homes, their most common response would probably be, "Get the bug spray!" Because students are not only being exposed to pesticides but are also developing patterns of behavior likely to continue throughout their lives. Discussions about…

  16. Chiral Synthons in Pesticide Syntheses

    NARCIS (Netherlands)

    Feringa, Bernard

    1988-01-01

    The use of chiral synthons in the preparation of enantiomerically pure pesticides is described in this chapter. Several routes to chiral synthons based on asymmetric synthesis or on natural products are illustrated. Important sources of chiral building blocks are reviewed. Furthermore the implicatio

  17. Simulating pesticide transport in urbanized catchments: a new spatially-distributed dynamic pesticide runoff model

    Science.gov (United States)

    Tang, Ting; Seuntjens, Piet; van Griensven, Ann; Bronders, Jan

    2016-04-01

    Urban areas can significantly contribute to pesticide contamination in surface water. However, pesticide behaviours in urban areas, particularly on hard surfaces, are far less studied than those in agricultural areas. Pesticide application on hard surfaces (e.g. roadsides and walkways) is of particular concern due to the high imperviousness and therefore high pesticide runoff potential. Experimental studies have shown that pesticide behaviours on and interactions with hard surfaces are important factors controlling the pesticide runoff potential, and therefore the magnitude and timing of peak concentrations in surface water. We conceptualized pesticide behaviours on hard surfaces and incorporated the conceptualization into a new pesticide runoff model. The pesticide runoff model was implemented in a catchment hydrological model WetSpa-Python (Water and Energy Transfer between Soil, Plants and Atmosphere, Python version). The conceptualization for pesticide processes on hard surfaces accounts for the differences in pesticide behaviour on different hard surfaces. Four parameters are used to describe the partitioning and wash-off of each pesticide on hard surfaces. We tested the conceptualization using experimental dataset for five pesticides on two types of hard surfaces, namely concrete and asphalt. The conceptualization gave good performance in accounting for the wash-off pattern for the modelled pesticides and surfaces, according to quantitative evaluations using the Nash-Sutcliffe efficiency and percent bias. The resulting pesticide runoff model WetSpa-PST (WetSpa for PeSTicides) can simulate pesticides and their metabolites at the catchment scale. Overall, it includes four groups of pesticide processes, namely pesticide application, pesticide interception by plant foliage, pesticide processes on land surfaces (including partitioning, degradation and wash-off on hard surface; partitioning, dissipation, infiltration and runoff in soil) and pesticide processes in

  18. Pesticide residue profile and nutrient characteristics of the Densu River Basin in Ghana

    International Nuclear Information System (INIS)

    The Densu River Basin is one of the largest agricultural areas in Ghana. About 80% of people living in this area rely on agricultural activities for subsistence. The practice of using pesticides such as organochlorines, organophosphates, carbamates, pyrethroids and several others in agriculture and public health programs have raised concerns about potentially adverse effects on human health and the environment. Assessment of human health implications of non-point sources within a river basin include pesticide residues analysis of water, sediment and fish and monitoring of physico-chemical parameters in waters that serve as source of drinking water for the entire community within the basin. In this study, a field survey was conducted to assess farmers' knowledge of safe handling and use of pesticides. Nutrient chemistry and surface water characteristics of the Densu River and its tributaries, type and levels of pesticide residues and their trends in water, sediment and fish in the basin were also evaluated. The study also assessed the health risk associated with pesticide contamination of fish from the Basin as well as the relationship between land use and groundwater contamination. Generally surface and ground water bodies in the Densu River basin were found to be polluted with respect to nutrients and pesticides. Waters from the basin were found to be fresh, slightly acidic, and weakly mineralized with low chemical constituents. Nitrate (NO3-N) levels in surface water ranged between 0.12 - 31.07 mgL-1 while ammonia was between 0.01 - 2.10 mgL-1 and that of phosphate was 0.012 - 2.45 mgL-1. Pesticide residues and metabolites detected in water, sediment and fish samples from the Densu River Basin were organochlorines. In an average 96% of fish samples, 13.69% of sediment and 3.30% of water samples, at least one pesticide residue was detected per sample. Of the numerous pesticides evaluated, γ -HCH, DDT, aldrin, dieldrin, DDE, endosulfan sulphate,

  19. Pesticide exposure and risk of Alzheimer's disease: a systematic review and meta-analysis.

    Science.gov (United States)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-01-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer's disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34; 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship. PMID:27581992

  20. Multiresidue Analysis of Pesticides in Soil by Liquid-Solid Extraction Procedure

    Directory of Open Access Journals (Sweden)

    Rada Đurović

    2012-01-01

    Full Text Available A multiresidue method for simultaneous determination of four pesticides (diazinon,acetochlor, aldrine and carbofuran belonging to different pesticide groups, extractedfrom soil samples, is described. The method presented is based on liquid-solid extraction(LSE and determination of pesticides, i.e. the pesticides were extracted by methanol-acetone mixture, purified on florisil column and eluted by ethyl acetate-acetone mixture.Optimization of the main parameters affecting the LSE procedure, such as the choiceof purification sorbent, as well as the elution solvent and its volume, were investigated indetails and optimized. Also, validation of the proposed method was done.Gas chromatography-mass spectrometry (GC-MS was used for detection and quantificationof the pesticides studied. Relative standard deviation (RSD and recovery values formultiple analysis of soil samples fortified with 30 μg/kg of each pesticide were below 8%and higher than 89%, respectively. Limits of detection (LOD for all the compounds studiedwere less than 4 μg/kg.

  1. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    Science.gov (United States)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-09-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship.

  2. Pesticide exposure and risk of Alzheimer’s disease: a systematic review and meta-analysis

    Science.gov (United States)

    Yan, Dandan; Zhang, Yunjian; Liu, Liegang; Yan, Hong

    2016-01-01

    Evidence suggests that lifelong cumulative exposure to pesticides may generate lasting toxic effects on the central nervous system and contribute to the development of Alzheimer’s disease (AD). A number of reports indicate a potential association between long-term/low-dose pesticide exposure and AD, but the results are inconsistent. Therefore, we conducted a meta-analysis to clarify this association. Relevant studies were identified according to inclusion criteria. Summary odds ratios (ORs) were calculated using fixed-effects models. A total of seven studies were included in our meta-analysis. A positive association was observed between pesticide exposure and AD (OR = 1.34; 95% confidence interval [CI] = 1.08, 1.67; n = 7). The summary ORs with 95% CIs from the crude and adjusted effect size studies were 1.14 (95% CI = 0.94, 1.38; n = 7) and 1.37 (95% CI = 1.09, 1.71; n = 5), respectively. The sensitivity analyses of the present meta-analysis did not substantially modify the association between pesticide exposure and AD. Subgroup analyses revealed that high-quality studies tended to show significant relationships. The present meta-analysis suggested a positive association between pesticide exposure and AD, confirming the hypothesis that pesticide exposure is a risk factor for AD. Further high-quality cohort and case-control studies are required to validate a causal relationship. PMID:27581992

  3. COMMUNICATING THE RISKS OF PESTICIDE EXPOSURE TO AGRICULTURAL WORKERS

    Science.gov (United States)

    The goals of the USEPA pesticide worker safety program are to protect human health and the environment by ensuring the competency of pesticide applicators to minimize pesticide exposure to occupational pesticide users and agricultural field workers, to assure use of pesticides, a...

  4. 40 CFR 170.230 - Pesticide safety training for handlers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pesticide safety training for handlers...) PESTICIDE PROGRAMS WORKER PROTECTION STANDARD Standard for Pesticide Handlers § 170.230 Pesticide safety... of restricted-use pesticides under part 171 of this chapter. (2) A handler who satisfies the...

  5. Pesticides and their effects on wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Driver, C.J.

    1994-07-01

    About 560 active ingredients are currently used as pesticides. Applications of these pesticides are made to agricultural lands and other areas inhabited by wildlife. Unfortunately, many agricultural-use pesticides also entail some measure of risk to organisms other than the pest species. Because testing of pesticides prior to registration cannot evaluate all the potential environmental-pesticide-wildlife/fish interactions, current methods of risk assessment do not always provide sufficient safety to nontarget organisms. This is evidenced by die-offs of fish and wildlife from applications of pesticides at environmentally {open_quotes}safe{close_quotes} rates, the linking of population declines of some species with agrochemical use, and observations of survival-threatening behavioral changes in laboratory and field animals exposed to typical field levels of pesticides. It is important to note, however, that the majority of pesticides, when properly applied, have not caused significant injury to wildlife. A brief summary of pesticide effects on wildlife and fish are presented for the common classes of pesticides in use today.

  6. The use and disposal of household pesticides.

    Science.gov (United States)

    Grey, Charlotte N B; Nieuwenhuijsen, Mark J; Golding, Jean

    2005-01-01

    Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed.

  7. The use and disposal of household pesticides

    International Nuclear Information System (INIS)

    Most pesticides are synthetic chemicals manufactured specifically for their toxic properties to the target species, and widely used globally. Several epidemiological studies in the United States have suggested health concerns arising from the chronic exposure of young children to pesticides in the domestic environment. In the UK very little is currently known about how nonoccupational pesticides are being used or disposed of. Any use of pesticides is a potential risk factor for children's exposure, and any potential exposure is likely to be reduced by the parents' adopting precautionary behaviour when using these pesticide products. This was investigated using a sample of 147 parents from the Avon Longitudinal Study of Parents and Children cohort in and around Bristol, through an in-depth interview between August and November 2001. The results of this study add to the understanding of the underlying behaviour of parents applying pesticide products in the home environment in the UK. Pesticides are readily available, and are normally purchased in do-it-yourself shops and supermarkets and mostly disposed of in domestic waste. Safety was stated by 45% of parents to be the most important factor to consider when buying a pesticide. When buying pesticide products, labels were stated to be the most important source of information about pesticides. However, a third of parents stated they would not follow the product label exactly when using a product, just under half felt labels were both inadequate and hard to understand, and about 10% of parents would not take notice of warnings on the pesticide label. Less than half of parents would use gloves when applying a pesticide, although the use of protective equipment such as gloves during the application of pesticides could greatly reduce the exposure. It is a public health concern that the instructions on the labels of products may not always be understood or followed, and further understanding of user behaviour is needed

  8. Equilibrium Dynamics of β-N-Methylamino-L-Alanine (BMAA) and Its Carbamate Adducts at Physiological Conditions

    Science.gov (United States)

    Zimmerman, David; Goto, Joy J.; Krishnan, Viswanathan V

    2016-01-01

    Elevated incidences of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia complex (ALS/PDC) is associated with β-methylamino-L-alanine (BMAA), a non-protein amino acid. In particular, the native Chamorro people living in the island of Guam were exposed to BMAA by consuming a diet based on the cycad seeds. Carbamylated forms of BMAA are glutamate analogues. The mechanism of neurotoxicity of the BMAA is not completely understood, and BMAA acting as a glutamate receptor agonist may lead to excitotoxicity that interferes with glutamate transport systems. Though the interaction of BMAA with bicarbonate is known to produce carbamate adducts, here we demonstrate that BMAA and its primary and secondary adducts coexist in solution and undergoes a chemical exchange among them. Furthermore, we determined the rates of formation/cleavage of the carbamate adducts under equilibrium conditions using two-dimensional proton exchange NMR spectroscopy (EXSY). The coexistence of the multiple forms of BMAA at physiological conditions adds to the complexity of the mechanisms by which BMAA functions as a neurotoxin. PMID:27513925

  9. Vibrational spectra study of fluorescent dendrimers built from the cyclotriphosphazene core with terminal dansyl and carbamate groups

    Science.gov (United States)

    Furer, V. L.; Vandyukova, I. I.; Vandyukov, A. E.; Fuchs, S.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2011-08-01

    The FTIR and FT Raman spectra of the "Janus"-type dendrimers, possessing five carbamate groups on one side and five fluorescent dansyl derivatives on the other side, with amide G1 and hydrazone G2 central linkages were studied. These surface-block dendrimers are obtained by the coupling of two different dendrons. The FTIR and FT-Raman spectra of the zero generation dendrons, built from the hexafunctional cyclotriphosphazene core, with five dansyl terminal groups and one carbamate G0 v and one oxybenzaldehyde function G0v have been recorded. The structural optimization and normal mode analysis were performed for dendron G0v on the basis of the density functional theory (DFT). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendron molecule G0v has a concave lens structure with planar -O-C6H4-CHdbnd O fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of dendron G0v were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The strong band 1597 cm -1 show marked changes of the optical density in dependence of substituents in the aromatic ring. The frequencies of ν(N-H) bands in the IR spectra reveal the presence of the different types of H-bonds in the dendrimers.

  10. Organophosphate and carbamate insecticides in agricultural waters and cholinesterase (ChE) inhibition in common carp (Cyprinus carpio)

    Science.gov (United States)

    Gruber, S.J.; Munn, M.D.

    1998-01-01

    Cholinesterase (ChE) activity was used as a biomarker for assessing exposure of common carp (Cyprinus carpio) to organophosphate and carbamate insecticides from irrigated agricultural waters. Carp were collected from a lake (Royal Lake) that receives most of its water from irrigation return flows and from a reference lake (Billy Clapp Lake) outside of the irrigation system. Results indicated that the mean whole-brain ChE activity of carp from Royal Lake (3.47 μmol/min/g tissue) was 34.2% less than that of carp from Billy Clapp Lake (5.27 μmol/min/g tissue) (p = 0.003). The depressed ChE activity in brain tissue of Royal Lake carp was in response to ChE-inhibiting insecticides detected in water samples in the weeks prior to tissue sampling; the most frequently detected insecticides included chlorpyrifos, azinphos-methyl, carbaryl, and ethoprop. Neither sex nor size appears to be a covariable in the analysis; ChE activity was not correlated with fish length or weight in either lake and there was no significant difference in ChE activity between the two sexes within each lake. Although organophosphate and carbamate insecticides can break down rapidly in the environment, this study suggests that in agricultural regions where insecticides are applied for extended periods of the year, nontarget aquatic biota may be exposed to high levels of ChE-inhibiting insecticides for a period of several months.

  11. Novel 2-aminopyrimidine carbamates as potent and orally active inhibitors of Lck: synthesis, SAR, and in vivo antiinflammatory activity.

    Science.gov (United States)

    Martin, Matthew W; Newcomb, John; Nunes, Joseph J; McGowan, David C; Armistead, David M; Boucher, Christina; Buchanan, John L; Buckner, William; Chai, Lilly; Elbaum, Daniel; Epstein, Linda F; Faust, Theodore; Flynn, Shaun; Gallant, Paul; Gore, Anu; Gu, Yan; Hsieh, Faye; Huang, Xin; Lee, Josie H; Metz, Daniela; Middleton, Scot; Mohn, Deanna; Morgenstern, Kurt; Morrison, Michael J; Novak, Perry M; Oliveira-dos-Santos, Antonio; Powers, David; Rose, Paul; Schneider, Stephen; Sell, Stephanie; Tudor, Yanyan; Turci, Susan M; Welcher, Andrew A; White, Ryan D; Zack, Debra; Zhao, Huilin; Zhu, Li; Zhu, Xiaotian; Ghiron, Chiara; Amouzegh, Patricia; Ermann, Monika; Jenkins, James; Johnston, David; Napier, Spencer; Power, Eoin

    2006-08-10

    The lymphocyte-specific kinase (Lck) is a cytoplasmic tyrosine kinase of the Src family expressed in T cells and NK cells. Genetic evidence in both mice and humans demonstrates that Lck kinase activity is critical for signaling mediated by the T cell receptor (TCR), which leads to normal T cell development and activation. A small molecule inhibitor of Lck is expected to be useful in the treatment of T cell-mediated autoimmune and inflammatory disorders and/or organ transplant rejection. In this paper, we describe the synthesis, structure-activity relationships, and pharmacological characterization of 2-aminopyrimidine carbamates, a new class of compounds with potent and selective inhibition of Lck. The most promising compound of this series, 2,6-dimethylphenyl 2-((3,5-bis(methyloxy)-4-((3-(4-methyl-1-piperazinyl)propyl)oxy)phenyl)amino)-4-pyrimidinyl(2,4-bis(methyloxy)phenyl)carbamate (43) exhibits good activity when evaluated in in vitro assays and in an in vivo model of T cell activation. PMID:16884310

  12. Exposure to non-persistent pesticides and thyroid function: A systematic review of epidemiological evidence.

    Science.gov (United States)

    Campos, Élida; Freire, Carmen

    2016-08-01

    Numerous pesticides are recognized for their endocrine-disrupting properties. Non-persistent pesticides such as organophosphates, dithiocarbamates and pyrethroids may interfere with thyroid function as suggested by animal studies. However, the influence of chronic exposure to these compounds on thyroidal functions in humans remains to be determined. The present study aimed to review epidemiological evidence for an association between exposure to non-persistent pesticides and circulating levels of thyroid hormones (thyroxin [T4] and triiodothyronine [T3]) and thyroid-stimulating hormone (TSH). A systematic review was conducted using MEDLINE, SCOPUS and Virtual Health Library (BVS) databases. Articles were limited to original studies and reports published in English, Portuguese or Spanish. Nineteen epidemiological studies were identified, 17 of which were cross-sectional, 14 were of occupationally exposed workers and 11 used exposure biomarkers. Fungicides and organophosphates (OP) insecticides were the most studied pesticides. Although methodological heterogeneity between studies was noted, particularly regarding study design, exposure assessment, and control of confounding, most of them showed associations with changes in T3 and T4, and/or TSH levels, while results from a few of these are consistent with experimental data supporting the findings that non-persistent pesticide exposure exerts hypothyroid-like effects. However, reporting quality was moderate to poor in 50% of the studies, particularly regarding method of selection of participants and discussion of external validity. Overall, current knowledge regarding the impact of non-persistent pesticides on human thyroid function is still limited. Given the widespread use of pesticides, future research should assess effects of exposure to currently-used pesticides in cohort studies combining comprehensive questionnaire-based assessment and biomarkers. Investigators need to pay particular attention to exposure

  13. Exposure to non-persistent pesticides and thyroid function: A systematic review of epidemiological evidence.

    Science.gov (United States)

    Campos, Élida; Freire, Carmen

    2016-08-01

    Numerous pesticides are recognized for their endocrine-disrupting properties. Non-persistent pesticides such as organophosphates, dithiocarbamates and pyrethroids may interfere with thyroid function as suggested by animal studies. However, the influence of chronic exposure to these compounds on thyroidal functions in humans remains to be determined. The present study aimed to review epidemiological evidence for an association between exposure to non-persistent pesticides and circulating levels of thyroid hormones (thyroxin [T4] and triiodothyronine [T3]) and thyroid-stimulating hormone (TSH). A systematic review was conducted using MEDLINE, SCOPUS and Virtual Health Library (BVS) databases. Articles were limited to original studies and reports published in English, Portuguese or Spanish. Nineteen epidemiological studies were identified, 17 of which were cross-sectional, 14 were of occupationally exposed workers and 11 used exposure biomarkers. Fungicides and organophosphates (OP) insecticides were the most studied pesticides. Although methodological heterogeneity between studies was noted, particularly regarding study design, exposure assessment, and control of confounding, most of them showed associations with changes in T3 and T4, and/or TSH levels, while results from a few of these are consistent with experimental data supporting the findings that non-persistent pesticide exposure exerts hypothyroid-like effects. However, reporting quality was moderate to poor in 50% of the studies, particularly regarding method of selection of participants and discussion of external validity. Overall, current knowledge regarding the impact of non-persistent pesticides on human thyroid function is still limited. Given the widespread use of pesticides, future research should assess effects of exposure to currently-used pesticides in cohort studies combining comprehensive questionnaire-based assessment and biomarkers. Investigators need to pay particular attention to exposure

  14. Multi-residue method for the determination of pesticides and pesticide metabolites in honeybees by liquid and gas chromatography coupled with tandem mass spectrometry--Honeybee poisoning incidents.

    Science.gov (United States)

    Kiljanek, Tomasz; Niewiadowska, Alicja; Semeniuk, Stanisław; Gaweł, Marta; Borzęcka, Milena; Posyniak, Andrzej

    2016-02-26

    A method for the determination of 200 pesticides and pesticide metabolites in honeybee samples has been developed and validated. Almost 98% of compounds included in this method are approved to use within European Union, as active substances of plant protection products or veterinary medicinal products used by beekeepers to control mites Varroa destructor in hives. Many significant metabolites, like metabolites of imidacloprid, thiacloprid, fipronil, methiocarb and amitraz, are also possible to detect. The sample preparation was based on the buffered QuEChERS method. Samples of bees were extracted with acetonitrile containing 1% acetic acid and then subjected to clean-up by dispersive solid phase extraction (dSPE) using a new Z-Sep+ sorbent and PSA. The majority of pesticides, including neonicotionoids and their metabolites, were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) but some of pesticides, especially pyrethroid insecticides, were analyzed by gas chromatography tandem mass spectrometry (GC-MS/MS). The procedure was validated according to the Guidance document SANCO/12571/2013 at four concentration levels: 1, 5, 10 and 100 ng/g bees and verified in the international proficiency test. The analysis of bee samples spiked at the limit of quantification (LOQ) showed about 98% mean recovery value (trueness) and 97% of analytes showed recovery in the required range of 70-120% and RSDr (precision) below 20%. Linearity and matrix effects were also established. The LOQs of pesticides were in the range of 1-100 ng/g. The developed method allows determination of insecticides at concentrations of 10 ng/g or less, except abamectin and tebufenozide. LOQ values are lower than the median lethal doses LD50 for bees. The method was used to investigate more than 70 honeybee poisoning incidents. Data about detected pesticides and their metabolites are included.

  15. Multi-residue method for the determination of pesticides and pesticide metabolites in honeybees by liquid and gas chromatography coupled with tandem mass spectrometry--Honeybee poisoning incidents.

    Science.gov (United States)

    Kiljanek, Tomasz; Niewiadowska, Alicja; Semeniuk, Stanisław; Gaweł, Marta; Borzęcka, Milena; Posyniak, Andrzej

    2016-02-26

    A method for the determination of 200 pesticides and pesticide metabolites in honeybee samples has been developed and validated. Almost 98% of compounds included in this method are approved to use within European Union, as active substances of plant protection products or veterinary medicinal products used by beekeepers to control mites Varroa destructor in hives. Many significant metabolites, like metabolites of imidacloprid, thiacloprid, fipronil, methiocarb and amitraz, are also possible to detect. The sample preparation was based on the buffered QuEChERS method. Samples of bees were extracted with acetonitrile containing 1% acetic acid and then subjected to clean-up by dispersive solid phase extraction (dSPE) using a new Z-Sep+ sorbent and PSA. The majority of pesticides, including neonicotionoids and their metabolites, were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) but some of pesticides, especially pyrethroid insecticides, were analyzed by gas chromatography tandem mass spectrometry (GC-MS/MS). The procedure was validated according to the Guidance document SANCO/12571/2013 at four concentration levels: 1, 5, 10 and 100 ng/g bees and verified in the international proficiency test. The analysis of bee samples spiked at the limit of quantification (LOQ) showed about 98% mean recovery value (trueness) and 97% of analytes showed recovery in the required range of 70-120% and RSDr (precision) below 20%. Linearity and matrix effects were also established. The LOQs of pesticides were in the range of 1-100 ng/g. The developed method allows determination of insecticides at concentrations of 10 ng/g or less, except abamectin and tebufenozide. LOQ values are lower than the median lethal doses LD50 for bees. The method was used to investigate more than 70 honeybee poisoning incidents. Data about detected pesticides and their metabolites are included. PMID:26830634

  16. Collembola and macroarthropod community responses to carbamate, organophosphate and synthetic pyrethroid insecticides: Direct and indirect effects

    Energy Technology Data Exchange (ETDEWEB)

    Frampton, Geoff K. [Ecology and Evolutionary Biology Group, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX (United Kingdom)]. E-mail: gkf@soton.ac.uk; Brink, Paul J. van den [Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Wageningen University, Department of Aquatic Ecology and Water Quality Management, Wageningen University and Research Centre, P.O. Box 8080, 6700 DD Wageningen (Netherlands)

    2007-05-15

    Non-target effects on terrestrial arthropod communities of the broad-spectrum insecticides chlorpyrifos and cypermethrin and the selective insecticide pirimicarb were investigated in winter wheat fields in summer. Effects of chlorpyrifos on arthropod abundance and taxonomic richness were consistently negative whereas effects of cypermethrin were negative for predatory arthropods but positive for soil surface Collembola. Pirimicarb effects were marginal, primarily on aphids and their antagonists, with no effect on the Collembola community. Collembola-predator ratios were significantly higher following cypermethrin treatment, suggesting that cypermethrin-induced increases in collembolan abundance represent a classical resurgence. Observations in other studies suggest Collembola resurgences may be typical after synthetic pyrethroid applications. Collembola responses to insecticides differed among species, both in terms of effect magnitude and persistence, suggesting that coarse taxonomic monitoring would not adequately detect pesticide risks. These findings have implications for pesticide risk assessments and for the selection of indicator species. - Direct and indirect insecticide effects differ among closely-related arthropod taxa; resurgence of Collembola may occur widely after synthetic pyrethroid insecticide applications.

  17. Fate of pesticides during beer brewing.

    Science.gov (United States)

    Inoue, Tomonori; Nagatomi, Yasushi; Suga, Keiko; Uyama, Atsuo; Mochizuki, Naoki

    2011-04-27

    The fates of more than 300 pesticide residues were investigated in the course of beer brewing. Ground malt artificially contaminated with pesticides was brewed via steps such as mashing, boiling, and fermentation. Analytical samples were taken from wort, spent grain, and beer produced at certain key points in the brewing process. The samples were extracted and purified with the QuEChERS (Quick Easy Cheap Effective Rugged and Safe) method and were then analyzed by LC-MS/MS using a multiresidue method. In the results, a majority of pesticides showed a reduction in the unhopped wort and were adsorbed onto the spent grain after mashing. In addition, some pesticides diminished during the boiling and fermentation. This suggests that the reduction was caused mainly by adsorption, pyrolysis, and hydrolysis. After the entire process of brewing, the risks of contaminating beer with pesticides were reduced remarkably, and only a few pesticides remained without being removed or resolved.

  18. Characterizing pesticide dissipation in food crops

    DEFF Research Database (Denmark)

    Fantke, Peter; Juraske, R.; Jolliet, O.

    2013-01-01

    Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure. Neverth......Ingestion of residues via consumption of food crops is the predominant exposure route of the general population toward pesticides. However, pesticide dissipation in crops constitutes a main source of uncertainty in estimating residues in harvested crop parts and subsequent human exposure....... Nevertheless, dissipation is a key mechanism in models assessing pesticide distribution in the cropenvironment and the magnitude of residues in harvest. We provide a consistent framework for characterizing pesticide dissipation in food crops for use in modeling approaches applied in health risk and impact...

  19. Antibiotic, Pesticide, and Microbial Contaminants of Honey: Human Health Hazards

    Directory of Open Access Journals (Sweden)

    Noori Al-Waili

    2012-01-01

    Full Text Available Agricultural contamination with pesticides and antibiotics is a challenging problem that needs to be fully addressed. Bee products, such as honey, are widely consumed as food and medicine and their contamination may carry serious health hazards. Honey and other bee products are polluted by pesticides, heavy metals, bacteria and radioactive materials. Pesticide residues cause genetic mutations and cellular degradation and presence of antibiotics might increase resistant human or animal's pathogens. Many cases of infant botulisms have been attributed to contaminated honey. Honey may be very toxic when produced from certain plants. Ingestion of honey without knowing its source and safety might be problematic. Honey should be labeled to explore its origin, composition, and clear statement that it is free from contaminants. Honey that is not subjected for analysis and sterilization should not be used in infants, and should not be applied to wounds or used for medicinal purposes. This article reviews the extent and health impact of honey contamination and stresses on the introduction of a strict monitoring system and validation of acceptable minimal concentrations of pollutants or identifying maximum residue limits for bee products, in particular, honey.

  20. Catalytic aziridination of electron-deficient olefins with an N-chloro-N-sodio carbamate and application of this novel method to asymmetric synthesis.

    Science.gov (United States)

    Minakata, Satoshi; Murakami, Yuta; Tsuruoka, Ryoji; Kitanaka, Shinsuke; Komatsu, Mitsuo

    2008-12-21

    A new method for the aziridination of electron-deficient olefins using an N-chloro-N-sodio carbamate is described; the reaction was promoted by phase-transfer catalysis (solid-liquid) and afforded aziridines from alpha,beta-unsaturated ketones, esters, sulfones and amides. PMID:19048156

  1. Quantum Chemical Studies on Solvents for Post-Combustion Carbon Dioxide Capture: Calculation of pKa and Carbamate Stability of Disubtituted Piperazines

    NARCIS (Netherlands)

    Gangarapu, S.; Wierda, G.J.; Marcelis, A.T.M.; Zuilhof, H.

    2014-01-01

    Piperazine is a widely studied solvent for post-combustion carbon dioxide capture. To investigate the possibilities of further improving this process, the electronic and steric effects of CH3, CH2F, CH2OH, CH2NH2, COCH3, and CN groups of 2,5-disubstituted piperazines on the pKa and carbamate stabili

  2. ORALLY ACTIVE CARBAMATE PRODRUGS OF THE SELECTIVE DOPAMINE AGONIST N-0437 - INVIVO ACTIVITIES IN THE 6-OHDA TURNING MODEL AND INVITRO ACTIVITIES

    NARCIS (Netherlands)

    DENDAAS, [No Value; DEBOER, P; TEPPER, PG; ROLLEMA, H; HORN, AS

    1991-01-01

    The in-vivo activities of eight carbamate prodrugs of the D2-agonist N-0437 were determined by examining the effects of the prodrugs, after their oral administration in rats with unilateral 6-OHDA lesions of the striatum. The resulting contralateral turning was used as an index of the activity of th

  3. [(18)F]Fluorobenzoyllysinepentanedioic Acid Carbamates: New Scaffolds for Positron Emission Tomography (PET) Imaging of Prostate-Specific Membrane Antigen (PSMA).

    Science.gov (United States)

    Yang, Xing; Mease, Ronnie C; Pullambhatla, Mrudula; Lisok, Ala; Chen, Ying; Foss, Catherine A; Wang, Yuchuan; Shallal, Hassan; Edelman, Hannah; Hoye, Adam T; Attardo, Giorgio; Nimmagadda, Sridhar; Pomper, Martin G

    2016-01-14

    Radiolabeled urea-based low-molecular weight inhibitors of the prostate-specific membrane antigen (PSMA) are under intense investigation as imaging and therapeutic agents for prostate and other cancers. In an effort to provide agents with less nontarget organ uptake than the ureas, we synthesized four (18)F-labeled inhibitors of PSMA based on carbamate scaffolds. 4-Bromo-2-[(18)F]fluorobenzoyllysineoxypentanedioic acid (OPA) carbamate [(18)F]23 and 4-iodo-2-[(18)F]fluorobenzoyllysine OPA carbamate [(18)F]24 in particular exhibited high target-selective uptake in PSMA+ PC3 PIP tumor xenografts, with tumor-to-kidney ratios of >1 by 4 h postinjection, an important benchmark. Because of its high tumor uptake (90% injected dose per gram of tissue at 2 h postinjection) and high tumor-to-organ ratios, [(18)F]23 is promising for clinical translation. Prolonged tumor-specific uptake demonstrated by [(18)F]24, which did not reach equilibrium during the 4 h study period, suggests carbamates as alternative scaffolds for mitigating dose to nontarget tissues. PMID:26629713

  4. A Novel Synthesis of N-Methyl-N-aryl Carbamates from Aromatic Amines and Dimethyl Carbonate Catalyzed by K2CO3/Bu4NBr

    Institute of Scientific and Technical Information of China (English)

    Zhen Lu SHEN; Xuan Zhen JIANG

    2004-01-01

    A facile synthesis of N-methyl-N-aryl carbamates from aromatic amines and dimethyl carbonate (DMC) has been achieved with high yields in the presence of potassium carbonate (K2CO3) and tetrabutylammonium bromide (Bu4NBr) under solvent-free conditions.

  5. Efficient Cellular Entry of (r-x-r)-Type Carbamate-Plasmid DNA Complexes and Its Implication for Noninvasive Topical DNA Delivery to Skin.

    Science.gov (United States)

    Vij, Manika; Natarajan, Poornemaa; Yadav, Amit K; Patil, Kiran M; Pandey, Tanuja; Gupta, Nidhi; Santhiya, Deenan; Kumar, Vaijayanti A; Fernandes, Moneesha; Ganguli, Munia

    2016-06-01

    Arginine-rich cell penetrating peptides are powerful tools for in vitro as well as in vivo delivery of a wide plethora of biomolecules. However, presence of consecutive arginine residues leads to enhanced amenability for proteolytic degradation as well as steric hindrances for membrane interactions which compromise its bioavailability. In order to overcome these limitations we previously reported a safe and stable octaarginine based oligomer, i.e., (r-x-r)4-carbamate, where the backbone amide linkages were replaced by carbamate linkages and 6-aminohexanoic acid based spacer moieties were incorporated for better flexibility, hydrophobicity, optimal spacing of guanidinium groups, and protection against proteolytic cleavage; resulting in improved transfection efficiency over its amide counterpart. In the present work we have investigated the mechanism behind this enhanced transfection efficiency and, based on our observations, demonstrate how the synergistic effect of rationalized oligomer designing, complex characteristics, and cell type contributes to overall effective intracellular delivery. Our results indicate that the (r-x-r)4-carbamate-plasmid DNA complexes primarily utilize lipid raft dependent pathway of cellular entry more than other pathways, and this possibly facilitates their increased entry in the lipid raft rich milieu of skin cells. We also emphasize the utility of oligomer (r-x-r)4-carbamate as an efficient carrier for topical delivery of nucleic acids in skin tissue. This carrier can be utilized for safe, efficient, and noninvasive delivery of therapeutically relevant macromolecular hydrophilic cargo like nucleic acids to skin. PMID:27175623

  6. A Mechanism-based 3D-QSAR Approach for Classification and Prediction of Acetylcholinesterase Inhibitory Potency of Organophosphate and Carbamate Analogs

    Science.gov (United States)

    Organophosphate (OP) and carbamate esters can inhibit acetylcholinesterase (AChE) by binding covalently to a serine residue in the enzyme active site, and their inhibitory potency depends largely on affinity for the enzyme and the reactivity of the ester. Despite this understandi...

  7. Ferric chloride-catalyzed reaction of [60]fullerene with tert-butyl N-substituted carbamates: synthesis of oxazolidino[4,5:1,2][60]fullerenes.

    Science.gov (United States)

    You, Xun; Wang, Guan-Wu

    2014-01-01

    The rare oxazolidinofullerenes have been prepared by the ferric chloride-catalyzed reaction of [60]fullerene with various tert-butyl N-substituted carbamates via t-Bu-O bond cleavage and heteroannulation under mild conditions. A possible mechanism for the formation of oxazolidinofullerenes is proposed. PMID:24328055

  8. Managing Pesticide Risks for Non-Target Ecosystems with Pesticide Risk Indicators: a Multicriteria Approach

    OpenAIRE

    Travisi, Chiara Maria; NIJKAMP Peter; Vighi, Marco; Giacomelli, Paolo

    2004-01-01

    In the search for effective pesticide risk management tools, the design of pesticide risk indicators is nowadays receiving increasing attention as a complement to more established regulatory strategies. In the present paper, we apply some recently developed pesticide risk indices and test their potential for management purposes. A pilot approach is proposed, which explores pesticide worst-case hazard scenarios at different space-time scales by means of a set of 5 ecotoxicological risk indices...

  9. Governing pesticide in vegetable production in Vietnam

    OpenAIRE

    Hoi, Van, P.

    2010-01-01

    The economic liberalization in Vietnam, initiated in the middle of the 1980s, contributed to the further intensification and expansion of private actor-engagement in agriculture and food-supply. Vietnamese farmers, who already considered applying pesticides the most effective manner to protect their vegetable crops from pests and disease attacks, started using more pesticides. Pesticide use in agriculture has, therefore, increased astonishingly in recent decades which causes increasing anxiet...

  10. Monitoring of pesticides in human milk

    International Nuclear Information System (INIS)

    After establishing proper analytical methodology for multiple pesticide residues, cotton-growing areas of Multan Division of Pakistan were surveyed and 40 samples of human milk from cotton pickers were collected during two crop seasons. Screening of these samples showed 72.5% contamination with 19 different pesticides/metabolites. The most frequently occurring pesticides were DDT and its metabolites, dimethoate, cyhalothrin, monocrotophos, profenofos and quinalphos. (author)

  11. Free Trade, Pesticide Regulation and NAFTA Harmonization

    OpenAIRE

    Freshwater, David

    2003-01-01

    Pesticides are an important farm input both in terms of cost and in terms of their impact on crop yields and quality. With freer trade in agricultural output, differences in cost of production, yield and quality can have a large effect on competitiveness. Thus there is an increased demand by farmers in Canada and the United States for harmonization of pesticide regulations, and in particular for the option to import registered pesticides for their own use. Under NAFTA the three national gover...

  12. Pesticides reduce regional biodiversity of stream invertebrates

    OpenAIRE

    Beketov, Mikhail A.; Kefford, Ben J.; Schäfer, Ralf B.; Liess, Matthias

    2013-01-01

    The biodiversity crisis is one of the greatest challenges facing humanity, but our understanding of the drivers remains limited. Thus, after decades of studies and regulation efforts, it remains unknown whether to what degree and at what concentrations modern agricultural pesticides cause regional-scale species losses. We analyzed the effects of pesticides on the regional taxa richness of stream invertebrates in Europe (Germany and France) and Australia (southern Victoria). Pesticides caused ...

  13. Effect of Endocrine Disruptor Pesticides: A Review

    OpenAIRE

    Benoit Roig; Olivier Thomas; Aghleb Bartegi; Wissem Mnif; Aicha Bouaziz; Aziza Ibn Hadj Hassine

    2011-01-01

    Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several yea...

  14. AFFINITY OF THE ALLIGATOR ESTROGEN RECEPTOR FOR SERUM PESTICIDE CONTAMINANTS

    Science.gov (United States)

    Top predators, like the American alligator (Alligator mississippiensis) bioaccumulate and biomagnify persistent pollutants, such as organochlorine pesticides. In a recently published study, several pesticides and pesticide metabolites not previously reported in alligator eggs wer...

  15. A mobile App for military operational entomology pesticide applications

    Science.gov (United States)

    Multiple field studies conducted for the Deployed War Fighter Protection (DWFP) research program have generated over 80 specific guidance points for innovative combinations of pesticide application equipment, pesticide formulations, and application techniques for aerosol and residual pesticide treat...

  16. Pesticides: Benefaction or Pandora's Box? A synopsis of the environmental aspects of 243 pesticides

    NARCIS (Netherlands)

    Linders JBHJ; Jansma JW; Mensink BJWG; Otermann K; ACT

    1994-01-01

    The report provides an overview of physical, chemical and environmental data of 243 pesticides. The data mentioned are based on confidential information supplied by the manufacturers of the pesticides. For all pesticides mentioned a Final Environmental File, which is public, is derived. Tables with

  17. 75 FR 74673 - Pesticides; Regulation To Clarify Labeling of Pesticides for Export; Notification to the...

    Science.gov (United States)

    2010-12-01

    ... AGENCY 40 CFR Part 168 RIN 2070-AJ53 Pesticides; Regulation To Clarify Labeling of Pesticides for Export...(a) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). As described in the Agency's... specificity to existing labeling regulations for the export of unregistered pesticide products and...

  18. 40 CFR 168.22 - Advertising of unregistered pesticides, unregistered uses of registered pesticides and FIFRA...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Advertising of unregistered pesticides, unregistered uses of registered pesticides and FIFRA section 24(c) registrations. 168.22 Section 168.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS STATEMENTS...

  19. Sorption of pesticides to aquifer minerals

    DEFF Research Database (Denmark)

    Clausen, Liselotte; Fabricius, Ida Lykke

    2000-01-01

    This paper summarizes results from a work were the sorption of five pesticides on seven minerals were studied in order to quantify the adsorption to different mineral surfaces. Investigated mineral phases are: quartz, calcite, kaolinite, a-alumina, and three iron oxides (2-line ferrihydrite......, goethite, lepidocrocite). Selected pesticides are: atrazine, isoproturon, mecoprop, 2,4-D, and bentazone. The results demonstrate that pesticides adsorb to pure mineral surfaces. However, the size of the adsorption depends on the type of pesticide and the type of mineral....

  20. Effect of Endocrine Disruptor Pesticides: A Review

    Directory of Open Access Journals (Sweden)

    Benoit Roig

    2011-06-01

    Full Text Available Endocrine disrupting chemicals (EDC are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air. For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health.

  1. Effect of endocrine disruptor pesticides: a review.

    Science.gov (United States)

    Mnif, Wissem; Hassine, Aziza Ibn Hadj; Bouaziz, Aicha; Bartegi, Aghleb; Thomas, Olivier; Roig, Benoit

    2011-06-01

    Endocrine disrupting chemicals (EDC) are compounds that alter the normal functioning of the endocrine system of both wildlife and humans. A huge number of chemicals have been identified as endocrine disruptors, among them several pesticides. Pesticides are used to kill unwanted organisms in crops, public areas, homes and gardens, and parasites in medicine. Human are exposed to pesticides due to their occupations or through dietary and environmental exposure (water, soil, air). For several years, there have been enquiries about the impact of environmental factors on the occurrence of human pathologies. This paper reviews the current knowledge of the potential impacts of endocrine disruptor pesticides on human health.

  2. PESTICIDE USE AND HUMAN HEALTH IN NORTHWESTERN JAMAICA

    OpenAIRE

    Ncube, Ngqabutho; Bessler, Patricia; Jolly, Pauline E; Tint, Kyaw; Fogo, Christopher; Binns, Alvin; Jolly, Curtis M.

    2007-01-01

    A number of studies have detected high levels of pesticide residues in surface water and aquatic life in Jamaica and acute pesticide poisoning is believed to be widespread there. Despite efforts by the Jamaican government to create awareness of the dangers of pesticides and adopt safe a pesticide disposal method, many farmers still display poor pesticide handling and disposal practices. The objectives of this study were to 1) describe pesticide use by farmers in northwestern Jamaica including...

  3. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Science.gov (United States)

    2010-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  4. 40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides product chemistry data requirements table. 158.2081 Section 158.2081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2081 Experimental use permit biochemical pesticides product chemistry data...

  5. 40 CFR 158.2173 - Experimental use permit microbial pesticides toxicology data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides toxicology data requirements table. 158.2173 Section 158.2173 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2173 Experimental use permit microbial pesticides toxicology data requirements table....

  6. 40 CFR 158.2174 - Experimental use permit microbial pesticides nontarget organisms and environmental fate data...

    Science.gov (United States)

    2010-07-01

    ... pesticides nontarget organisms and environmental fate data requirements table. 158.2174 Section 158.2174 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2174 Experimental use permit microbial pesticides...

  7. Evidence of carbamate resistance in urban populations of Anopheles gambiae s.s. mosquitoes resistant to DDT and deltamethrin insecticides in Lagos, South-Western Nigeria

    Directory of Open Access Journals (Sweden)

    Oduola Adedayo O

    2012-06-01

    Full Text Available Abstract Background Resistance monitoring is essential in ensuring the success of insecticide based vector control programmes. This study was carried out to assess the susceptibility status of urban populations of Anopheles gambiae to carbamate insecticide being considered for vector control in mosquito populations previously reported to be resistant to DDT and permethrin. Methods Two – three day old adult female Anopheles mosquitoes reared from larval collections in 11 study sites from Local Government Areas of Lagos were exposed to test papers impregnated with DDT 4%, deltamethrin 0.05% and propoxur 0.1% insecticides. Additional tests were carried out to determine the susceptibility status of the Anopheles gambiae population to bendiocarb insecticide. Members of the A. gambiae complex, the molecular forms, were identified by PCR assays. The involvement of metabolic enzymes in carbamate resistance was assessed using Piperonyl butoxide (PBO synergist assays. The presence of kdr-w/e and ace-1R point mutations responsible for DDT-pyrethroid and carbamate resistance mechanisms was also investigated by PCR. Results Propoxur resistance was found in 10 out of the 11 study sites. Resistance to three classes of insecticides was observed in five urban localities. Mortality rates in mosquitoes exposed to deltamethrin and propoxur did not show any significant difference (P > 0.05 but was significantly higher (P A. gambiae s.s (M form. The kdr -w point mutation at allelic frequencies between 45%-77% was identified as one of the resistant mechanisms responsible for DDT and pyrethroid resistance. Ace-1R point mutation was absent in the carbamate resistant population. However, the possible involvement of metabolic resistance was confirmed by synergistic assays conducted. Conclusion Evidence of carbamate resistance in A. gambiae populations already harbouring resistance to DDT and permethrin is a clear indication that calls for the implementation of

  8. 氨基甲酸酯淀粉浆料的制备及上浆性能%Manufacture and Sizing Performance of Carbamate Starch Size Mixture

    Institute of Scientific and Technical Information of China (English)

    刘志军; 许冬生

    2011-01-01

    探讨氨基甲酸酯淀粉的取代度对氨基甲酸酯淀粉浆料上浆性能的影响.通过改变氧化铵对淀粉的投料比,制备了一系列具有不同变性程度的氨基甲酸酯淀粉,对不同取代度的氨基甲酸酯淀粉浆料的浆液性能及对棉纤维的黏附性能进行了测试.结果表明:当取代度不超过0.053时,随氨基甲酸酯淀粉取代度的提高,浆液黏度降低,热稳定性提高,对棉纤维的黏着力增大.指出:氨基甲酸酯变性有利于改善淀粉对纯棉经纱的上浆性能.%Effect of carbamate starch substitution degree on size mixture property was discussed. Through changing feed ratio of ammonium chloride to starch,a series of carbamate starch with different substitution degree were made. Sizing property of carbamate starch with different substitution degree and adhesion performance to cotton fiber were tested. The result shows when the substitution degree is less 0. 053 and substitution degree of carbamate starch is increasing,sizing viscosity is reduced, the thermal stability is increased, the adhesion to cotton fiber is increased. It is pointed out that sizing property of carbamate starch to pure cotton yarn can be improved.

  9. Synthesis and reactivity of cyclic-carbamate derivatives%环状氨基甲酸酯衍生物的合成及反应研究

    Institute of Scientific and Technical Information of China (English)

    王静; 郭爽; 王家喜

    2011-01-01

    Cyclic carbamate has been prepared by the reaction of ethanolamine with dimethyl carbonate as raw material and zinc acetate as catalyst. The cyclic carbamate reacted with methyl acrylate producing methyl 3- (2-oxo-oxazolidin-3-yl) propanoate, which reacted with n-butylamine and 1,6-hexanediamine to give mono and bis cyclic carbamate derivatives. The attack of amine to carbonyl of heterocyclic ring of carbamate produced the hydroxylethyl substituted urea, while the attack to carbon-oxygen bond generated carbamic acid, which further underwent dehydration forming cyclic urea and/or de-carbon dioxide forming polyamine. The products were characterized by NMR and FT-IR. The reaction mechanism is finally proposed.%以乙醇胺和碳酸二甲酯为原料,在醋酸锌的催化下合成环状氨基甲酸酯,与丙烯酸甲酯反应制备3-(2-噁唑烷酮)丙酸甲酯,在K2CO3催化下进一步与正丁胺、1,6-己二胺发生酰胺化反应,得到了单、双环状氨基甲酸酯衍生物.有机胺与环状氨基甲酸酯的羰基反应形成羟乙基取代脲,与烷氧基反应形成开环的胺基甲酸,该化合物进一步脱水形成环状脲,脱二氧化碳形成多胺化合物.用NMR和红外谱图对开环产物进行表征,并初步探讨了其反应历程.

  10. Application of a radiometric enzymic method for monitoring organophosphorus and carbamate insecticide residues in water of the Danube River

    International Nuclear Information System (INIS)

    Pesticide residue analyses are conventionally based on gas chromatography. These analytic procedures include tedious extraction and clear-up manipulations prior to the actual gas chromatographic determinations. Radioenzymatic method was recently applied in a residue monitoring programme on the Danube River. The programme has demonstrated that the radioenzymatic method has many advantages as a monitoring procedure in aquatic environment. Quick information can be gained without tedious sample clear-up procedure. The anticholinesteratic pesticides and the anticholinesteratic activities can be detected

  11. Use of electroencephalography (EEG) to assess CNS changes produced by pesticides with different modes of action: Effects of permethrin, deltamethrin, fipronil, imidacloprid, carbaryl, and triadimefon

    International Nuclear Information System (INIS)

    The electroencephalogram (EEG) is an apical measure, capable of detecting changes in brain neuronal activity produced by internal or external stimuli. We assessed whether pesticides with different modes of action produced different changes in the EEG of adult male Long–Evans rats. The EEG was recorded using two montages (visual cortex referenced to the cerebellum and to the frontal cortex) in unrestrained rats at the time of peak behavioral effects. Pesticides included: permethrin and deltamethrin (Type I and Type II pyrethroids; 2 h), fipronil (single and repeated doses; phenylpyrazole; 6 h), imidacloprid (neonicotinoid; 2 h), carbaryl (carbamate; 0.5 h), and triadimefon (triazole; 1 h), using dosages that produced approximately an ED30 or an ED50–ED80 change in motor activity. Permethrin (43, 100 mg/kg) increased amplitudes or areas (delta, alpha, or gamma bands) in the EEG. Deltamethrin (2.5, 5.5 mg/kg) reduced the amplitudes or areas of the delta, theta, alpha, beta, and gamma bands, but the changes were not dose-related. A single treatment with fipronil (25, 50 mg/kg, but not 5, 10 mg/kg) decreased gamma band area. Additional changes in the delta, theta, and gamma bands were observed when fipronil (5, 10 mg/kg) was administered for 14 days. Imidacloprid (50, 100 mg/kg) did not alter the EEG. Carbaryl (10, 50 mg/kg) decreased theta area, and decreased delta and increased beta frequency. Triadimefon (75, 150 mg/kg) produced minimal changes in the EEG. The results show that the EEG is affected differently by approximately equipotent doses of pesticides with different modes of action. - Highlights: • Pesticides with different modes of action have different effects on in vivo rodent EEG. • The EEG was also changed differently after single vs. repeated treatment with fipronil. • The data suggest that EEG may be used as an apical measure for detecting chemical effects on the central nervous system

  12. Pesticide poisoning in the developing world--a minimum pesticides list

    DEFF Research Database (Denmark)

    Eddleston, Michael; Karalliedde, Lakshman; Buckley, Nick;

    2002-01-01

    In parts of the developing world, pesticide poisoning causes more deaths than infectious diseases. Use of pesticides is poorly regulated and often dangerous; their easy availability also makes them a popular method of self-harm. In 1985, the UN Food and Agriculture Organisation (FAO) produced...... a voluntary code of conduct for the pesticide industry in an attempt to limit the harmful effects of pesticides. Unfortunately, a lack of adequate government resources in the developing world makes this code ineffective, and thousands of deaths continue today. WHO has recommended that access to highly toxic...... pesticides be restricted--where this has been done, suicide rates have fallen. Since an Essential Drugs List was established in 1977, use of a few essential drugs has rationalised drug use in many regions. An analogous Minimum Pesticides List would identify a restricted number of less dangerous pesticides...

  13. Pattern of pesticide storage before pesticide self-poisoning in rural Sri Lanka

    DEFF Research Database (Denmark)

    Mohamed, Fahim; Manuweera, Gamini; Gunnell, David;

    2009-01-01

    BACKGROUND: Deliberate self-poisoning with agricultural pesticides is the commonest means of suicide in rural Asia. It is mostly impulsive and facilitated by easy access to pesticides. The aim of this large observational study was to investigate the immediate source of pesticides used for self-harm...... the particular pesticide for self-harm were its easy accessibility (n = 311, 46%) or its popularity as a suicide agent in their village (n = 290, 43%). CONCLUSION: Three quarters of people who ingested pesticides in acts of self-harm used products that were available within the home or in close proximity......; relatively few patients purchased the pesticide for the act. The study highlights the importance of reducing the accessibility of toxic pesticides in the domestic environment....

  14. Enantioseparation of Neutral Compounds on a Quinine Carbamate-Immobilized Zirconia in Reversed-Phase Capillary Electrochromatography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mun Rak; Gwon, Ju Rim; Park, Jung Hag [Yeungnam University, Gyeongsan (Korea, Republic of)

    2010-01-15

    Quinine (QN) is a weak anion-exchange type chiral selector and QN-based silica stationary phases have been widely used for enantioseparation of acidic chiral analytes in HPLC and recently in CEC. In this work we report enantioseparation of non-acidic chiral analytes on a quinine carbamate-immobilized zirconia (QNZ) in reversed-phase (RP) CEC. Influences of pH, composition of the buffer, acetonitrile content and the applied voltage on enantioseparation were examined. Enantiomers of the analytes investigated are well separated in acetonitrile/phosphate buffer mobile phases. Separation data on QNZ were compared to those on QN-bonded silica (QNS). Retention was longer but better enantioselectivity and resolution were obtained on QNZ than QNS.

  15. Influence of Solvent on Reaction Path to Synthesis of Methyl N-Phenyl Carbamate from Aniline, CO2 and Methanol

    Institute of Scientific and Technical Information of China (English)

    安华良; 张丽丽; 苑保国; 赵新强; 王延吉

    2014-01-01

    Methyl N-phenyl carbamate (MPC), an important organic chemical, can be synthesized from aniline, CO2 and methanol. Catalyst Cu-Fe/ZrO2-SiO2 was first prepared and its catalytic performance for MPC synthesis was evaluated. Then the influence of solvent on the reaction path of MPC synthesis was investigated. It is found that the reaction intermediate is different with acetonitrile or methanol as a solvent. With acetonitrile as a solvent, the synthesis of MPC follows the reaction path with diphenyl urea as the intermediate, while with methanol as a solvent the reaction occurs via the reaction path with dimethyl carbonate as the intermediate. The catalytic mecha-nism of cooperative catalysis comprising metal sites, Lewis acid sites and Lewis base sites is proposed according to different reaction intermediates.

  16. Effect of two formulations of benzimidazole carbamates on the viability of cysts of Echinococcus granulosus in vivo

    Directory of Open Access Journals (Sweden)

    Daniel-Mwuambete K.

    2003-12-01

    Full Text Available Two different preparations, solution and suspension, of three benzimidazole carbamate drugs, mebendazole, albendazole and ricobendazole, were compared by analyzing their in vivo activity against Echinococcus granulosus cysts in a mouse model. Polyvinylpyrrolidone was used for the elaboration of drug solutions and these formulations manifested better results in terms of reduction of number of viable hydatid cysts in mice than the reference drug suspensions. The effect was more prominent on mebendazole-treated mice, at doses of 25-50 mg/kg. There was a correlation between ED50 and pharmacokinetical parameters of AUC0∞ and Cmax , showing that a significant improvement on solubility affects the in vivo activity of these drugs.

  17. Effect of two formulations of benzimidazole carbamates on the viability of cysts of Echinococcus granulosus in vivo.

    Science.gov (United States)

    Daniel-Mwuambete, K; Ponce-Gordo, F; Torrado, J; Torrado, S; Cuesta-Bandera, C

    2003-12-01

    Two different preparations, solution and suspension, of three benzimidazole carbamate drugs, mebendazole, albendazole and ricobendazole, were compared by analyzing their in vivo activity against Echinococcus granulosus cysts in a mouse model. Polyvinylpyrrolidone was used for the elaboration of drug solutions and these formulations manifested better results in terms of reduction of number of viable hydatid cysts in mice than the reference drug suspensions. The effect was more prominent on mebendazole-treated mice, at doses of 25-50 mg/kg. There was a correlation between ED50 and pharmacokinetical parameters of AUC0-infinity and Cmax, showing that a significant improvement on solubility affects the in vivo activity of these drugs. PMID:14710635

  18. Ethyl carbamate in alcoholic beverages from Mexico (tequila, mezcal, bacanora, sotol) and Guatemala (cuxa): market survey and risk assessment.

    Science.gov (United States)

    Lachenmeier, Dirk W; Kanteres, Fotis; Kuballa, Thomas; López, Mercedes G; Rehm, Jürgen

    2009-01-01

    Ethyl carbamate (EC) is a recognized genotoxic carcinogen, with widespread occurrence in fermented foods and beverages. No data on its occurrence in alcoholic beverages from Mexico or Central America is available. Samples of agave spirits including tequila, mezcal, bacanora and sotol (n=110), and of the sugarcane spirit cuxa (n=16) were purchased in Mexico and Guatemala, respectively, and analyzed for EC. The incidence of EC contamination was higher in Mexico than in Guatemala, however, concentrations were below international guideline levels (<0.15 mg/L). Risk assessment found the Margin of Exposure (MOE) in line with that of European spirits. It is therefore unlikely that EC plays a role in high rates of liver cirrhosis reported in Mexico.

  19. Ethyl Carbamate in Alcoholic Beverages from Mexico (Tequila, Mezcal, Bacanora, Sotol and Guatemala (Cuxa: Market Survey and Risk Assessment

    Directory of Open Access Journals (Sweden)

    Jürgen Rehm

    2009-01-01

    Full Text Available Ethyl carbamate (EC is a recognized genotoxic carcinogen, with widespread occurrence in fermented foods and beverages. No data on its occurrence in alcoholic beverages from Mexico or Central America is available. Samples of agave spirits including tequila, mezcal, bacanora and sotol (n=110, and of the sugarcane spirit cuxa (n=16 were purchased in Mexico and Guatemala, respectively, and analyzed for EC. The incidence of EC contamination was higher in Mexico than in Guatemala, however, concentrations were below international guideline levels (<0.15 mg/L. Risk assessment found the Margin of Exposure (MOE in line with that of European spirits. It is therefore unlikely that EC plays a role in high rates of liver cirrhosis reported in Mexico.

  20. Anthelmintic profile of methyl 5(6)-(4-methylpiperidin-1-yl) carbonylbenzimidazole-2-carbamate in experimental helminthiases.

    Science.gov (United States)

    Gupta, S; Khan, A M; Jain, M K; Katiyar, J C; Naim, S S; Singh, S K; Sharma, S

    1990-05-01

    Biological evaluation of methyl 5(6)-(4-methylpiperidin-1-yl) carbonylbenzimidazole-2-carbamate against Ancylostoma ceylanicum, Nippostrongylus brasiliensis, Syphacia obvelata, Hymenolepis nana, H. diminuta and Cysticercus fasciolaris in experimental animals is reported. The compound (mg/kg) causes 100% elimination of A. ceylanicum (25 x 1), N. brasiliensis (100 x 1), S. obvelata (50 x 1), H. nana (250 x 3) and C. fasciolaris (50 x 10). It was also effective against the developing larvae (L3, L4 and L5) of A. ceylanicum at a single oral dose of 100 mg/kg. Another study indicated that the compound elicits 100% response within 32 hr of drug administration. The drug is well tolerated and LD50 is greater than 4500 mg/kg.