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Sample records for chlorpyrifos oxon implications

  1. Particulate and gas-phase products from the atmospheric degradation of chlorpyrifos and chlorpyrifos-oxon

    Science.gov (United States)

    Borrás, Esther; Ródenas, Milagros; Vázquez, Mónica; Vera, Teresa; Muñoz, Amalia

    2015-12-01

    The phosphorothioate structure is highly present in several pesticides. However, there is a lack of information about its degradation process in air and the secondary pollutants formed. Herein, the atmospheric reactions of chlorpyrifos, one of the most world-used insecticide, and its main degradation product - chlorpyrifos-oxon - are described. The photo-oxidation under the presence of NOx was studied in a large outdoor simulation chamber for both chlorpyrifos and chlorpyrifos-oxon, observing a rapid degradation (Half lifetime < 3.5 h for both compounds). Also, the photolysis reactions of both were studied. The formation of particulate matter (aerosol mass yield ranged 6-59%) and gaseous products were monitored. The chemical composition of minor products was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as 3,5,6-trichloropyridin-2-ol and ethyl 3,5,6-trichloropyridin-2-yl hydrogen phosphate. An atmospheric degradation mechanism has been amplified based on an oxidation started with OH-nucleophilic attack to Pdbnd S bond.

  2. Inhibition of recombinant human carboxylesterase 1 and 2 and monoacylglycerol lipase by chlorpyrifos oxon, paraoxon and methyl paraoxon

    International Nuclear Information System (INIS)

    Oxons are the bioactivated metabolites of organophosphorus insecticides formed via cytochrome P450 monooxygenase-catalyzed desulfuration of the parent compound. Oxons react covalently with the active site serine residue of serine hydrolases, thereby inactivating the enzyme. A number of serine hydrolases other than acetylcholinesterase, the canonical target of oxons, have been reported to react with and be inhibited by oxons. These off-target serine hydrolases include carboxylesterase 1 (CES1), CES2, and monoacylglycerol lipase. Carboxylesterases (CES, EC 3.1.1.1) metabolize a number of xenobiotic and endobiotic compounds containing ester, amide, and thioester bonds and are important in the metabolism of many pharmaceuticals. Monoglyceride lipase (MGL, EC 3.1.1.23) hydrolyzes monoglycerides including the endocannabinoid, 2-arachidonoylglycerol (2-AG). The physiological consequences and toxicity related to the inhibition of off-target serine hydrolases by oxons due to chronic, low level environmental exposures are poorly understood. Here, we determined the potency of inhibition (IC50 values; 15 min preincubation, enzyme and inhibitor) of recombinant CES1, CES2, and MGL by chlorpyrifos oxon, paraoxon and methyl paraoxon. The order of potency for these three oxons with CES1, CES2, and MGL was chlorpyrifos oxon > paraoxon > methyl paraoxon, although the difference in potency for chlorpyrifos oxon with CES1 and CES2 did not reach statistical significance. We also determined the bimolecular rate constants (kinact/KI) for the covalent reaction of chlorpyrifos oxon, paraoxon and methyl paraoxon with CES1 and CES2. Consistent with the results for the IC50 values, the order of reactivity for each of the three oxons with CES1 and CES2 was chlorpyrifos oxon > paraoxon > methyl paraoxon. The bimolecular rate constant for the reaction of chlorpyrifos oxon with MGL was also determined and was less than the values determined for chlorpyrifos oxon with CES1 and CES2 respectively

  3. Inhibition of recombinant human carboxylesterase 1 and 2 and monoacylglycerol lipase by chlorpyrifos oxon, paraoxon and methyl paraoxon

    Energy Technology Data Exchange (ETDEWEB)

    Crow, J. Allen; Bittles, Victoria; Herring, Katye L.; Borazjani, Abdolsamad [Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762 (United States); Potter, Philip M. [Department of Chemical Biology and Therapeutics, St. Jude Children' s Research Hospital, 332 N. Lauderdale, Memphis, TN 38105 (United States); Ross, Matthew K., E-mail: mross@cvm.msstate.edu [Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762 (United States)

    2012-01-01

    Oxons are the bioactivated metabolites of organophosphorus insecticides formed via cytochrome P450 monooxygenase-catalyzed desulfuration of the parent compound. Oxons react covalently with the active site serine residue of serine hydrolases, thereby inactivating the enzyme. A number of serine hydrolases other than acetylcholinesterase, the canonical target of oxons, have been reported to react with and be inhibited by oxons. These off-target serine hydrolases include carboxylesterase 1 (CES1), CES2, and monoacylglycerol lipase. Carboxylesterases (CES, EC 3.1.1.1) metabolize a number of xenobiotic and endobiotic compounds containing ester, amide, and thioester bonds and are important in the metabolism of many pharmaceuticals. Monoglyceride lipase (MGL, EC 3.1.1.23) hydrolyzes monoglycerides including the endocannabinoid, 2-arachidonoylglycerol (2-AG). The physiological consequences and toxicity related to the inhibition of off-target serine hydrolases by oxons due to chronic, low level environmental exposures are poorly understood. Here, we determined the potency of inhibition (IC{sub 50} values; 15 min preincubation, enzyme and inhibitor) of recombinant CES1, CES2, and MGL by chlorpyrifos oxon, paraoxon and methyl paraoxon. The order of potency for these three oxons with CES1, CES2, and MGL was chlorpyrifos oxon > paraoxon > methyl paraoxon, although the difference in potency for chlorpyrifos oxon with CES1 and CES2 did not reach statistical significance. We also determined the bimolecular rate constants (k{sub inact}/K{sub I}) for the covalent reaction of chlorpyrifos oxon, paraoxon and methyl paraoxon with CES1 and CES2. Consistent with the results for the IC{sub 50} values, the order of reactivity for each of the three oxons with CES1 and CES2 was chlorpyrifos oxon > paraoxon > methyl paraoxon. The bimolecular rate constant for the reaction of chlorpyrifos oxon with MGL was also determined and was less than the values determined for chlorpyrifos oxon with CES1

  4. Comparative toxicity of chlorpyrifos, diazinon, malathion and their oxon derivatives to larval Rana boylii

    Energy Technology Data Exchange (ETDEWEB)

    Sparling, D.W. [Cooperative Wildlife Research Laboratory, Department of Zoology and Center for Ecology, Southern Illinois University, LS II, MS6504, Carbondale, IL 62901 (United States)]. E-mail: dsparl@siu.edu; Fellers, G. [Western Ecology Research Center, U.S. Geological Survey, Point Reyes National Seashore, Point Reyes, CA 94956 (United States)

    2007-06-15

    Organophosphorus pesticides (OPs) are ubiquitous in the environment and are highly toxic to amphibians. They deactivate cholinesterase, resulting in neurological dysfunction. Most chemicals in this group require oxidative desulfuration to achieve their greatest cholinesterase-inhibiting potencies. Oxon derivatives are formed within liver cells but also by bacterial decay of parental pesticides. This study examines the toxicity of chlorpyrifos, malathion and diazinon and their oxons on the foothill yellow-legged frog (Rana boylii). R. boylii is exposed to agricultural pesticides in the California Central Valley. Median lethal concentrations of the parental forms during a 96 h exposure were 3.00 mg/L (24 h) for chlorpyrifos, 2.14 mg/L for malathion and 7.49 mg/L for diazinon. Corresponding oxons were 10 to 100 times more toxic than their parental forms. We conclude that environmental concentrations of these pesticides can be harmful to R. boylii populations. - Laboratory tests on the toxicity of OP insecticides and their oxons suggest that they may be acutely lethal to amphibians at ecologically relevant concentrations.

  5. Toxicity of chlorpyrifos and chlorpyrifos oxon in a transgenic mouse model of the human paraoxonase (PON1) Q192R polymorphism

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-08-01

    The Q192R polymorphism of paraoxonase (PON1) has been shown to affect hydrolysis of organophosphorus compounds. The Q192 and R192 alloforms exhibit equivalent catalytic efficiencies of hydrolysis for diazoxon, the oxon form of the pesticide (DZ). However, the R192 alloform has a higher catalytic efficiency of hydrolysis than does the Q192 alloform for chlorpyrifos oxon (CPO), the oxon form of the pesticide chlorpyrifos (CPS). The current study examined the relevance of these observations for in-vivo exposures to chlorpyrifos and chlorpyrifos oxon. Methods Using a transgenic mouse model we examined the relevance of the Q192R polymorphism for exposure to CPS and CPO in vivo. Transgenic mice were generated that expressed either human PON1Q192 or PON1R192 at equivalent levels, in the absence of endogenous mouse PON1. Dose-response and time course experiments were performed on adult mice exposed dermally to CPS or CPO. Morbidity and acetylcholinesterase (AChE) activity in the brain and diaphragm were determined in the first 24 h following exposure. Results Mice expressing PON1Q192 were significantly more sensitive to CPO, and to a lesser extent CPS, than were mice expressing PON1R192. The time course of inhibition following exposure to 1.2 mg/kg CPO revealed maximum inhibition of brain AChE at 6?12 h, with PON1R192, PON1Q192, and PON1? /? mice exhibiting 40, 70 and 85% inhibition, respectively, relative to control mice. The effect of PON1 removal on the dose?response curve for CPS exposure was remarkably consistent with a PBPK/PD model of CPS exposure. Conclusion These results indicate that individuals expressing only the PON1Q192 allele would be more sensitive to the adverse effects of CPO or CPS exposure, especially if they are expressing a low level of plasma PON1Q192.

  6. Inhibition of Recombinant Human Carboxylesterase 1 and 2 and Monoacylglycerol Lipase by Chlorpyrifos Oxon, Paraoxon and Methyl Paraoxon

    OpenAIRE

    Crow, J. Allen; Bittles, Victoria; Herring, Katye L.; Borazjani, Abdolsamad; Potter, Philip M.; Ross, Matthew K.

    2011-01-01

    Oxons are the bioactivated metabolites of organophosphorus insecticides formed via cytochrome P450 monooxygenase-catalyzed desulfuration of the parent compound. Oxons react covalently with the active site serine residue of serine hydrolases, thereby inactivating the enzyme. A number of serine hydrolases other than acetylcholinesterase, the canonical target of oxons, have been reported to react with and be inhibited by oxons. These off-target serine hydrolases include carboxylesterase 1 (CES1)...

  7. Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells

    Energy Technology Data Exchange (ETDEWEB)

    Flaskos, J., E-mail: flaskos@vet.auth.gr [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Nikolaidis, E. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Harris, W. [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Sachana, M. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Hargreaves, A.J., E-mail: alan.hargreaves@ntu.ac.uk [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

    2011-11-15

    Previous work in our laboratory has shown that sub-lethal concentrations (1-10 {mu}M) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1-10 {mu}M) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: Black-Right-Pointing-Pointer Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells Black-Right-Pointing-Pointer Acetylcholinesterase exhibits sustained inhibition throughout exposure Black-Right-Pointing-Pointer The levels of neurofilament heavy chain and GAP-43

  8. Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells

    International Nuclear Information System (INIS)

    Previous work in our laboratory has shown that sub-lethal concentrations (1–10 μM) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1–10 μM) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: ► Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells ► Acetylcholinesterase exhibits sustained inhibition throughout exposure ► The levels of neurofilament heavy chain and GAP-43 protein are reduced ► Neurofilament heavy chain forms aggregates in cell

  9. Acetylcholinesterase inhibition in the threeridge mussel (Amblema plicata) by chlorpyrifos: implications for biomonitoring

    Science.gov (United States)

    Doran, W.J.; Cope, W.G.; Rada, R.G.; Sandheinrich, M.B.

    2001-01-01

    The effects of chlorpyrifos, an organophosphorus insecticide, were examined on the activity of the nervous system enzyme acetylcholinesterase (AChE) in the threeridge mussel Amblema plicata in a 24-day laboratory test. Thirty-six mussels in each of seven treatments (18 mussels per duplicate) were exposed to chlorpyrifos (0.1, 0.2, 0.3, 0.6, and 1.2 mg/L), a solvent (acetone), and a solvent-free (well water) control for 12, 24, or 96 h. The activity of AChE was measured in the anterior adductor muscle of eight mussels from each treatment after exposure. To assess potential latent effects, six mussels from each treatment were removed after 24 h of exposure and transferred to untreated water for a 21-day holding period; AChE activity was measured on three mussels from each treatment at 7 and 21 days of the holding period. The activity of AChE in chlorpyrifos-exposed mussels did not differ from controls after 12 or 24 h of exposure (t- test, P>0.05), but was significantly less than controls after 96 h (t- test, P=0.01). AChE activity did not vary among mussels at 24 h of exposure (i.e., Day 0 of holding period) and those at Day 7 and Day 21 of the holding period. Overall changes in AChE activity of mussels during the test were unrelated to individual chlorpyrifos concentrations and exposure times (repeated measure ANOVA; (P=0.06). A power analysis revealed that the sample size must be increased from 2 to 5 replicates (8 to 20 mussels per time interval and test concentration) to increase the probability of detecting significant differences in AChE activity. This calculated increase in sample size has potential implications for future biomonitoring studies with chlorpyrifos and unionid mussels.

  10. Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

    International Nuclear Information System (INIS)

    Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. - Highlights: • Chlorpyrifos-poisoned patients have adducts on protein tyrosine. • Diethoxyphosphate-tyrosine does not lose an alkyl group. • Proteins in addition to AChE and BChE are modified by organophosphates

  11. Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Li, Bin, E-mail: binli@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Eyer, Peter, E-mail: peter.eyer@lrz.uni-muenchen.de [Walther-Straub-Institut Für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München (Germany); Eddleston, Michael, E-mail: M.Eddleston@ed.ac.uk [Clinical Pharmacology Unit, University of Edinburgh, Edinburgh (United Kingdom); Jiang, Wei, E-mail: wjiang@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Schopfer, Lawrence M., E-mail: lmschopf@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States); Lockridge, Oksana, E-mail: olockrid@unmc.edu [Eppley Institute, University of Nebraska Medical Center, Omaha, NE 68198-5950 (United States)

    2013-06-15

    Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. - Highlights: • Chlorpyrifos-poisoned patients have adducts on protein tyrosine. • Diethoxyphosphate-tyrosine does not lose an alkyl group. • Proteins in addition to AChE and BChE are modified by organophosphates.

  12. Characterization of Chlorpyrifos Induced Apoptosis in Placental Cells

    OpenAIRE

    Saulsbury, Marilyn D.; Heyliger, Simone O.; Wang, Kaiyu; Round, Dorothy

    2007-01-01

    The mechanism by which chlorpyrifos exerts its toxicity in fetal and perinatal animals has yet to be elucidated. Since the placenta is responsible for transport of nutrients and is a major supplier hormones to the fetus, exposure to xenobiotics that alter the function or viability of placenta cells could ostensibly alter the development of the fetus. In this study, JAR cells were used to determine if CPF and the metabolites 3,5,6-trichloro-2-pyridinol (TCP) and chlorpyrifos-oxon (CPO) are tox...

  13. A Human Life-Stage Physiologically Based Pharmacokinetic and Pharmacodynamic Model for Chlorpyrifos: Development and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Jordan N.; Hinderliter, Paul M.; Timchalk, Charles; Bartels, M. J.; Poet, Torka S.

    2014-08-01

    Sensitivity to chemicals in animals and humans are known to vary with age. Age-related changes in sensitivity to chlorpyrifos have been reported in animal models. A life-stage physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model was developed to computationally predict disposition of CPF and its metabolites, chlorpyrifos-oxon (the ultimate toxicant) and 3,5,6-trichloro-2-pyridinol (TCPy), as well as B-esterase inhibition by chlorpyrifos-oxon in humans. In this model, age-dependent body weight was calculated from a generalized Gompertz function, and compartments (liver, brain, fat, blood, diaphragm, rapid, and slow) were scaled based on body weight from polynomial functions on a fractional body weight basis. Blood flows among compartments were calculated as a constant flow per compartment volume. The life-stage PBPK/PD model was calibrated and tested against controlled adult human exposure studies. Model simulations suggest age-dependent pharmacokinetics and response may exist. At oral doses ≥ 0.55 mg/kg of chlorpyrifos (significantly higher than environmental exposure levels), 6 mo old children are predicted to have higher levels of chlorpyrifos-oxon in blood and higher levels of red blood cell cholinesterase inhibition compared to adults from equivalent oral doses of chlorpyrifos. At lower doses that are more relevant to environmental exposures, the model predicts that adults will have slightly higher levels of chlorpyrifos-oxon in blood and greater cholinesterase inhibition. This model provides a computational framework for age-comparative simulations that can be utilized to predict CPF disposition and biological response over various postnatal life-stages.

  14. Esterases activity in the axolotl Ambystoma mexicanum exposed to chlorpyrifos and its implication to motor activity.

    Science.gov (United States)

    Robles-Mendoza, Cecilia; Zúñiga-Lagunes, Sebastian R; Ponce de León-Hill, Claudia A; Hernández-Soto, Jesús; Vanegas-Pérez, Cecilia

    2011-10-01

    The axolotl Ambystoma mexicanum is a neotenic salamander considered a good biological model due to its ability to regenerate limbs, tail, brain and heart cells. Nevertheless, severe reduction of A. mexicanum wild populations in the lacustrine area of Xochimilco, the natural habitat of the axolotl, could be related to several environmental pressures as the presence of organophosphate pesticides (OPPs), intensively applied in agricultural activities in Xochimilco. Thus the aim of this study was to evaluate the effect of environmentally realistic chlorpyrifos (CPF) concentrations, a OPP commonly used in this zone, on esterases activity (acetylcholinesterase and carboxylesterase) and bioconcentration of CPF and to relate them with the motor activity of A. mexicanum juveniles. Axolotls were exposed 48 h to 0.05 and 0.1mg CPF/L, and the responses were evaluated at the end of the CPF exposure. Results suggest that CPF is bioconcentrated into axolotls and that the CPF internal concentrations are related with the observed inhibition activity of AChE (>50%) and CbE (≈ 50%). CPF concentration responsible of the inhibition of the 50% of AChE activity (IC50) was estimated in 0.04 mg CPF/L; however IC50 for CbE activity was not possible to calculate since inhibition levels were lower than 50%, results that suggest a higher resistance of CbE enzymatic activity to CPF. However, motor activity was a more sensitive endpoint to CPF poisoning since time that axolotls spent active and walking, frequency and speed of swimming, frequency of prey attack were reduced >90% of control groups. The motor activity alterations in the axolotl could be related with the registered esterases inhibition. Thus important alterations on axolotls were identified even at short time and low concentrations of CPF exposure. Also, it was possible to link biochemical responses as esterases activity with higher levels of biological organization as behavior. This study provides tools for the regulation of the

  15. In Vitro Rat Hepatic and Intestinal Metabolism of the Organophosphate Pesticides Chlorpyrifos and Diazinon

    Energy Technology Data Exchange (ETDEWEB)

    Poet, Torka S.(BATTELLE (PACIFIC NW LAB)); Wu, Hong (BATTELLE (PACIFIC NW LAB)); Kousba, Ahmed A.(BATTELLE (PACIFIC NW LAB)); Timchalk, Charles (Pacific Northwest National Laboratory)

    2003-04-01

    Chlorpyrifos (CPF) and diazinon (DZN) are thionophosphorus organophosphate, insecticides; their toxicity is mediated through CYP450 metabolism to CPF-oxon and DZN-oxon, respectively. Conversely, CYP450s also detoxify these OPs to trichloropyridinol (TCP) and 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMHP), respectively. In addition, A-esterase metabolism of CPF- and DZN-oxon also form TCP and IMHP. This study evaluated the role intestinal and hepatic metabolism may play in the first-pass elimination of CPF and DZN. Similar CYP450- and A-esterase-mediated metabolic profiles were demonstrated in microsomes from liver or isolated intestinal enterocytes. In enterocyte microsomes, the CYP450 metabolic efficiency (Vmax/Km) for metabolism to the oxon metabolites was~5-fold greater for CPF than DZN. Compared on a per nmol P450 basis, the Vmax for CPF in enterocytes was~2-3 times higher than in liver microsomes for the production of CPF-oxon and TCP. The affinity (Km) for the metabolism of CPF to CPF-oxon was comparable in liver and enterocyte microsomes, however the enterocyte Km for TCP production was higher (lower affinity). The smaller volume of intestine, lower amount of CYP450, and higher Km for TCP in the enterocyte microsomes, resulted in a lower catalytic efficiency (2 and 62 times) than in liver for oxon and TCP. A-esterase-mediated metabolism of CPF- and DZN-oxon was also demonstrated in liver and enterocyte microsomes. Although A-esterase affinity for the substrates were comparable in hepatic and enterocyte microsomes, the Vmax were 48 - to 275-fold, in the liver. These results suggest that intestinal metabolism may impact first-pass metabolism of CPF and DZN, especially following low-dose oral exposures.

  16. Fate of 14C-Chlorpyrifos Insecticide in Sunflower Seeds and Oil and the Effect of Processing According to Industrial Practice

    International Nuclear Information System (INIS)

    Ethyl -1- 14C-chlorpyrifos and some of its degradation products have been prepared for the present investigation. Sunflower plants were treated with 14C-chlorpyrifos under conditions simulating local agricultural practice. 14C-residue in seeds were determined at different time intervals. At harvest time about 8 % of 14C-activity was associated with oil. The methanol soluble 14C-residues accounted for 0.8 % of the total seed residues, while the cake contained about 80 % of the total residues. About 46 % of the 14C-activity in the crude oil could be eliminated by simulated commercial processes locally used for oil refining. The refined oil had a 14C- residue level of about 21 ppm. Chromatographic analysis of crude and refined oil revealed the presence of the parent compound together with three metabolites which were identified as chlorpyrifos oxon, desethyl chlorpyrifos, and desethyl chlorpyrifos oxon in addition to an unknown compound. Methanol extract of the cake revealed the presence of the parent compound and its oxon as free compounds. Acid hydrolysis of the conjugated metabolites in the methanol extract yielded desethyl chlorpyrifos and 3, 5, 6- trichloro-2-hydroxypyridine

  17. Prenatal Dexamethasone Augments the Sex-Selective Developmental Neurotoxicity of Chlorpyrifos: Implications for Vulnerability after Pharmacotherapy for Preterm Labor

    OpenAIRE

    Slotkin, Theodore A.; Card, Jennifer; Infante, Alice; Seidler, Frederic J

    2013-01-01

    Glucocorticoids are routinely given in preterm labor and are also elevated by maternal stress; organophosphate exposures are virtually ubiquitous, so coexposures to these two agents are pervasive. We administered dexamethasone to pregnant rats on gestational days 17–19 at a standard therapeutic dose (0.2 mg/kg); offspring were then given chlorpyrifos on postnatal days 1–4, at a dose (1 mg/kg) that produces barely-detectable (

  18. Effects of Chlorpyrifos and Chlorpyrifos-Oxon on the Dynamics and Movement of Mitochondria in Rat Cortical NeuronsS⃞

    OpenAIRE

    Middlemore-Risher, Mary-Louise; Adam, Bao-Ling; Lambert, Nevin A.; Alvin V Terry

    2011-01-01

    Organophosphate (OP)-based pesticides have been used extensively for decades, and as a result, they have become almost ubiquitous in our environment. There is clinical and animal evidence to suggest that chronic exposures to OPs can lead to cognitive dysfunction and other neurological abnormalities, although the mechanism for these effects is unknown. We previously reported that repeated, subthreshold exposures (defined as doses not associated with signs of acute toxicity) to the commonly use...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-08-01

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

  20. THE CANNABINOID RECEPTOR ANTAGONIST AM251 INCREASES PARAOXON AND CHLORPYRIFOS OXON TOXICITY IN RATS

    OpenAIRE

    Liu, Jing; Pope, Carey

    2014-01-01

    Organophosphorus anticholinesterases (OPs) elicit acute toxicity by inhibiting acetylcholinesterase (AChE), leading to acetylcholine accumulation and overstimulation of cholinergic receptors. Endocannabinoids (eCBs, e.g., arachidonoyl ethanolamide [AEA] and 2-arachidonoyl glycerol [2-AG]) are neuromodulators that regulate neurotransmission by reducing neurotransmitter release. The eCBs are degraded by the enzymes fatty acid amide hydrolase (FAAH, primarily involved in hydrolysis of AEA) and m...

  1. Integrated biomarker analysis of chlorpyrifos metabolism and toxicity in the earthworm Aporrectodea caliginosa.

    Science.gov (United States)

    Sanchez-Hernandez, Juan C; Narvaez, C; Sabat, P; Martínez Mocillo, S

    2014-08-15

    To increase our understanding about the mode of toxic action of organophosphorus pesticides in earthworms, a microcosm experiment was performed with Aporrectodea caliginosa exposed to chlorpyrifos-spiked soils (0.51 and 10 mg kg(-1) dry soil) for 3 and 21 d. Acetylcholinesterase (AChE), carboxylesterase (CbE), cytochrome P450-dependent monooxygenase (CYP450), and glutathione S-transferase (GST) activities were measured in the body wall of earthworms. With short-term exposure, chlorpyrifos inhibited CbE activity (51-89%) compared with controls in both treated groups, whereas AChE activity was depressed in the 10-mg kg(-1) group (87% inhibition). With long-term exposure, chlorpyrifos strongly inhibited all esterase activities (84-97%). Native electrophoresis revealed three AChE isozymes, two of which showed a decreased staining corresponding to the level of pesticide exposure. The impact of chlorpyrifos on CbE activity was also corroborated by zymography. CYP450 activity was low in unexposed earthworms, but it increased (1.5- to 2.4-fold compared to controls) in the earthworms exposed to both chlorpyrifos concentrations for 3d. Bioactivation of chlorpyrifos was determined by incubating the muscle homogenate in the presence of chlorpyrifos and NAD(H)2. The mean (±SD, n=40) bioactivation rate in the unexposed earthworms was 0.74±0.27 nmol NAD(H)2 oxidized min(-1) mg(-1) protein, and a significant induction was detected in the low/short-term exposure group. GST activity significantly increased (33-35% of controls) in earthworms short-term exposed to both chlorpyrifos concentrations. Current data showed that CYP450 and GST activities had a prominent role in the initial exposure to the organophosphorus. With short-term exposure, CbE activity was also a key enzyme in the non-catalytic detoxification of chlorpyrifos-oxon, thereby reducing its impact on AChE activity, before it became saturated at t=21 d. Results indicate that A. caliginosa detoxify efficiently

  2. The In Vivo Quantitation of Diazinon, chlorpyrifos, and Their Major Metabolites in Rat Blood for the Refinement of a Physiologically-Based Pharmacokinetic/Pharmacodynamic Models

    Energy Technology Data Exchange (ETDEWEB)

    Busby, A.; Kousba, A.; Timchalk, C.

    2004-01-01

    Chlorpyrifos (CPF)(O,O-diethyl-O-[3,5,6-trichloro-2-pyridyl]-phosphorothioate, CAS 2921-88-2), and diazinon (DZN)(O,O-diethyl-O-2-isopropyl-4-methyl-6-pyrimidyl thiophosphate, CAS 333-41-5) are commonly encountered organophosphorus insecticides whose oxon metabolites (CPF-oxon and DZN-oxon) have the ability to strongly inhibit acetylcholinesterase, an enzyme responsible for the breakdown of acetylcholine at nerve synapses. Chlorpyrifos-oxon and DZN-oxon are highly unstable compounds that degrade via hepatic, peripheral blood, and intestinal metabolism to the more stable metabolites, TCP (3,5,6-trichloro-2-pyridinol, CAS not assigned) and IMHP (2-isopropyl-6-methyl-4-pyrimidinol, CAS 2814-20-2), respectively. Studies have been performed to understand and model the chronic and acute toxic effects of CPF and DZN individually but little is known about their combined effects. The purpose of this study was to improve physiologically based pharmacokinetic/ pharmacodynamic (PBPK/PD) computational models by quantifying concentrations of CPF and DZN and their metabolites TCP and IMHP in whole rat blood, following exposure to the chemicals individually or as a mixture. Male Sprague-Dawley rats were orally dosed with 60 mg/kg of CPF, DZN, or a mixture of these two pesticides. When administered individually DZN and CPF were seen to reach their maximum concentration at ~3 hours post-dosing. When given as a mixture, both DZN and CPF peak blood concentrations were not achieved until ~6 hours post-dosing and the calculated blood area under the curve (AUC) for both chemicals exceeded those calculated following the single dose. Blood concentrations of IMHP and TCP correlated with these findings. It is proposed that the higher AUC obtained for both CPF and DZN as a mixture resulted from competition for the same metabolic enzyme systems.

  3. Highly efficient oxidation of alcohols using Oxone(R) as oxidant catalyzed by ruthenium complex under mild reaction conditions

    Institute of Scientific and Technical Information of China (English)

    Zi Qiang Lei; Jian Qiang Wang; Peng Hua Yan

    2008-01-01

    Aromatic and alkyl alcohols were oxidized to the corresponding aldehydes or ketones at room temperature with high conversion and selectivity using Oxone (2KHSO5·KHSO4·K2SO4) as oxidant catalyzed by ruthenium complex Quin-Ru-Quin (where Quin = 8-hydroxyquinoline). The reaction time is very short and the preparation of complex is simple. 2008 Zi Qiang Lei. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  4. Transferable residues from dog fur and plasma cholinesterase inhibition in dogs treated with a flea control dip containing chlorpyrifos.

    Science.gov (United States)

    Boone, J S; Tyler, J W; Chambers, J E

    2001-11-01

    We studied chlorpyrifos, an insecticide present in a commercial dip for treating ectoparasites in dogs, to estimate the amount of transferable residues that children could obtain from their treated pets. Although the chlorpyrifos dip is no longer supported by the manufacturer, the methodology described herein can help determine transferable residues from other flea control insecticide formulations. Twelve dogs of different breeds and weights were dipped using the recommended guidelines with a commercial, nonprescription chlorpyrifos flea dip for 4 consecutive treatments at 3-week intervals (nonshampoo protocol) and another 12 dogs were dipped with shampooing between dips (shampoo protocol). The samples collected at 4 hr and 7, 14, and 21 days after treatment in the nonshampoo protocol averaged 971, 157, 70, and 26 microg chlorpyrifos, respectively; in the shampoo protocol the samples averaged 459, 49, 15, and 10 microg, respectively. The highest single sample was about 7,000 microg collected at 4 hr. The pretreatment specific activities in the plasma of the dogs were about 75 nmol/min/mg protein for butyrylcholinesterase (BChE), and 9 nmol/min/mg protein for acetylcholinesterase (AChE). BChE was inhibited 50-75% throughout the study, and AChE was inhibited 11-18% in the nonshampoo protocol; inhibition was not as great in the shampoo protocol. There was no correlation (pdogs. Transferable residues had largely dissipated during the three weeks after treatment, with the largest decrease occurring during the first week. Greater plasma ChE inhibition was observed at 7 days than at 4 hr, probably reflecting the bioactivation of chlorpyrifos to chlorpyrifos-oxon. Plasma cholinesterase activity did not return to control levels during the 3-week period. The differences between the shampoo and nonshampoo protocols were explained by differences in the techniques of the dip applicators.

  5. Transferable residues from dog fur and plasma cholinesterase inhibition in dogs treated with a flea control dip containing chlorpyrifos.

    Science.gov (United States)

    Boone, J S; Tyler, J W; Chambers, J E

    2001-11-01

    We studied chlorpyrifos, an insecticide present in a commercial dip for treating ectoparasites in dogs, to estimate the amount of transferable residues that children could obtain from their treated pets. Although the chlorpyrifos dip is no longer supported by the manufacturer, the methodology described herein can help determine transferable residues from other flea control insecticide formulations. Twelve dogs of different breeds and weights were dipped using the recommended guidelines with a commercial, nonprescription chlorpyrifos flea dip for 4 consecutive treatments at 3-week intervals (nonshampoo protocol) and another 12 dogs were dipped with shampooing between dips (shampoo protocol). The samples collected at 4 hr and 7, 14, and 21 days after treatment in the nonshampoo protocol averaged 971, 157, 70, and 26 microg chlorpyrifos, respectively; in the shampoo protocol the samples averaged 459, 49, 15, and 10 microg, respectively. The highest single sample was about 7,000 microg collected at 4 hr. The pretreatment specific activities in the plasma of the dogs were about 75 nmol/min/mg protein for butyrylcholinesterase (BChE), and 9 nmol/min/mg protein for acetylcholinesterase (AChE). BChE was inhibited 50-75% throughout the study, and AChE was inhibited 11-18% in the nonshampoo protocol; inhibition was not as great in the shampoo protocol. There was no correlation (pdogs. Transferable residues had largely dissipated during the three weeks after treatment, with the largest decrease occurring during the first week. Greater plasma ChE inhibition was observed at 7 days than at 4 hr, probably reflecting the bioactivation of chlorpyrifos to chlorpyrifos-oxon. Plasma cholinesterase activity did not return to control levels during the 3-week period. The differences between the shampoo and nonshampoo protocols were explained by differences in the techniques of the dip applicators. PMID:11712994

  6. Role of genetic polymorphism of human plasma paraoxonase/arylesterase in hydrolysis of the insecticide metabolites chlorpyrifos oxon and paraoxon.

    OpenAIRE

    Furlong, C E; Richter, R J; Seidel, S L; Motulsky, A G

    1988-01-01

    Plasma paraoxonase is a polymorphic enzyme that hydrolyzes paraoxon, the neurotoxic, active metabolite of the insecticide parathion. This enzyme is specified by at least two alleles with frequencies of about .7 and .3 among Caucasoid populations. A specific assay was developed that measured the activity of human plasma paraoxonase without interference from serum albumin which contributes significantly to the hydrolytic breakdown of paraoxon at the high pH values used in many previous assays. ...

  7. Internal Concentration and Time Are Important Modifiers of Toxicity: The Case of Chlorpyrifos on Caenorhabditis elegans.

    Science.gov (United States)

    Roh, Ji-Yeon; Lee, Hyun-Jeoung; Kwon, Jung-Hwan

    2016-09-01

    The internal concentration of chemicals in exposed organisms changes over time due to absorption, distribution, metabolism, and excretion processes since chemicals are taken up from the environment. Internal concentration and time are very important modifiers of toxicity when biomarkers are used to evaluate the potential hazards and risks of environmental pollutants. In this study, the responses of molecular biomarkers, and the fate of chemicals in the body, were comprehensively investigated to determine cause-and-effect relationships over time. Chlorpyrifos (CP) was selected as a model chemical, and Caenorhabditis elegans was exposed to CP for 4 h using the passive dosing method. Worms were then monitored in fresh medium during a 48-h recovery regime. The mRNA expression of genes related to CYP metabolism (cyp35a2 and cyp35a3) increased during the constant exposure phase. The body residue of CP decreased once it reached a peak level during the early stage of exposure, indicating that the initial uptake of CP rapidly induced biotransformation with the synthesis of new CYP metabolic proteins. The residual chlorpyrifos-oxon concentration, an acetylcholinesterase (AChE) inhibitor, continuously increased even after the recovery regime started. These delayed toxicokinetics seem to be important for the extension of AChE inhibition for up to 9 h after the start of the recovery regime. Comprehensive investigation into the molecular initiation events and changes in the internal concentrations of chemical species provide insight into response causality within the framework of an adverse outcome pathway.

  8. PON1 status does not influence cholinesterase activity in Egyptian agricultural workers exposed to chlorpyrifos

    International Nuclear Information System (INIS)

    Animal studies have shown that paraoxonase 1 (PON1) genotype can influence susceptibility to the organophosphorus pesticide chlorpyrifos (CPF). However, Monte Carlo analysis suggests that PON1 genotype may not affect CPF-related toxicity at low exposure conditions in humans. The current study sought to determine the influence of PON1 genotype on the activity of blood cholinesterase as well as the effect of CPF exposure on serum PON1 in workers occupationally exposed to CPF. Saliva, blood and urine were collected from agricultural workers (n = 120) from Egypt's Menoufia Governorate to determine PON1 genotype, blood cholinesterase activity, serum PON1 activity towards chlorpyrifos-oxon (CPOase) and paraoxon (POase), and urinary levels of the CPF metabolite 3,5,6-trichloro-2-pyridinol (TCPy). The PON1 55 (P ≤ 0.05) but not the PON1 192 genotype had a significant effect on CPOase activity. However, both the PON1 55 (P ≤ 0.05) and PON1 192 (P ≤ 0.001) genotypes had a significant effect on POase activity. Workers had significantly inhibited AChE and BuChE after CPF application; however, neither CPOase activity nor POase activity was associated with ChE depression when adjusted for CPF exposure (as determined by urinary TCPy levels) and stratified by PON1 genotype. CPOase and POase activity were also generally unaffected by CPF exposure although there were alterations in activity within specific genotype groups. Together, these results suggest that workers retained the capacity to detoxify chlorpyrifos-oxon under the exposure conditions experienced by this study population regardless of PON1 genotype and activity and that effects of CPF exposure on PON1 activity are minimal. -- Highlights: ► CPF exposure resulted in an increase in TCPy and decreases in BuChE and AChE. ► CPOase activity decreased in subjects with the PON1 55LM and PON1 55 MM genotypes. ► Neither PON1 genotype nor CPOase activity had an effect on BuChE or AChE inhibition.

  9. PON1 status does not influence cholinesterase activity in Egyptian agricultural workers exposed to chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, Corie A., E-mail: cellison@buffalo.edu [Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Crane, Alice L., E-mail: alcrane@buffalo.edu [Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Bonner, Matthew R., E-mail: mrbonner@buffalo.edu [Department of Social and Preventive Medicine, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Knaak, James B., E-mail: jbknaak@aol.com [Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Browne, Richard W., E-mail: rwbrowne@buffalo.edu [Department of Biotechnical and Clinical Laboratory Sciences, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Lein, Pamela J., E-mail: pjlein@ucdavis.edu [Department of Molecular Biosciences, University of California School of Veterinary Medicine, Davis, CA 95618 (United States); Olson, James R., E-mail: jolson@buffalo.edu [Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214 (United States); Department of Social and Preventive Medicine, State University of New York at Buffalo, Buffalo, NY 14214 (United States)

    2012-12-15

    Animal studies have shown that paraoxonase 1 (PON1) genotype can influence susceptibility to the organophosphorus pesticide chlorpyrifos (CPF). However, Monte Carlo analysis suggests that PON1 genotype may not affect CPF-related toxicity at low exposure conditions in humans. The current study sought to determine the influence of PON1 genotype on the activity of blood cholinesterase as well as the effect of CPF exposure on serum PON1 in workers occupationally exposed to CPF. Saliva, blood and urine were collected from agricultural workers (n = 120) from Egypt's Menoufia Governorate to determine PON1 genotype, blood cholinesterase activity, serum PON1 activity towards chlorpyrifos-oxon (CPOase) and paraoxon (POase), and urinary levels of the CPF metabolite 3,5,6-trichloro-2-pyridinol (TCPy). The PON1 55 (P ≤ 0.05) but not the PON1 192 genotype had a significant effect on CPOase activity. However, both the PON1 55 (P ≤ 0.05) and PON1 192 (P ≤ 0.001) genotypes had a significant effect on POase activity. Workers had significantly inhibited AChE and BuChE after CPF application; however, neither CPOase activity nor POase activity was associated with ChE depression when adjusted for CPF exposure (as determined by urinary TCPy levels) and stratified by PON1 genotype. CPOase and POase activity were also generally unaffected by CPF exposure although there were alterations in activity within specific genotype groups. Together, these results suggest that workers retained the capacity to detoxify chlorpyrifos-oxon under the exposure conditions experienced by this study population regardless of PON1 genotype and activity and that effects of CPF exposure on PON1 activity are minimal. -- Highlights: ► CPF exposure resulted in an increase in TCPy and decreases in BuChE and AChE. ► CPOase activity decreased in subjects with the PON1 55LM and PON1 55 MM genotypes. ► Neither PON1 genotype nor CPOase activity had an effect on BuChE or AChE inhibition.

  10. Transformation of Chlorpyrifos and Chlorpyrifos-Methyl in Prairie Pothole Porewaters

    Science.gov (United States)

    Anderson, R. M.; Chin, Y. P.

    2014-12-01

    The prairie pothole region (PPR) extends over approximately 700,000 km2 in the Great Plains region in United States and Canada and is a critical breeding ground for migratory waterfowl, as well as an important ecosystem for diverse invertebrates and aquatic plants (van der Valk, 2003). Consisting of up to 12 million permanent and temporary depressional wetlands, the PPR is negatively impacted by non-point source pesticide pollution due to extensive agricultural development in the region. Recent studies have shown that high (mM) levels of sulfate in the pothole lakes are capable of abiotically reducing dinitroaniline and chloroacetanilide pesticides (Zeng, 2011; Zeng, 2012). In this study the transformation of the organophosphorus pesticide chlorpyrifos (CP) and its analog chlorpyrifos-methyl (CPM) was studied using pore waters sampled from two pothole lakes. CP and CPM have been found to react in the laboratory with sulfur species via a SN2 mechanism, with degradation by sulfur compounds occurring faster than hydrolysis at high pH (Wu, 2006). To date the reaction of CP and CPM in natural environments with sulfur species has not been studied. Chlorpyrifos-methyl underwent rapid degradation in the presence of reduced sulfur species in pore water, while chlorpyrifos degradation occurred at significantly slower rates. Both CP and CPM degradation occurred at comparable rates to what has been previously observed in the laboratory (Wu, 2006). References van der Valk, Arnold G., and Roger L. Pederson. "The SWANCC decision and its implications for prairie potholes." Wetlands 23.3 (2003): 590-596. Wu, Tong, Qiu Gan, and Urs Jans. "Nucleophilic Substitution of Phosphorothionate Ester Pesticides with Bisulfide (HS-) and Polysulfides (Sn2-)." Environmental science & technology 40.17 (2006): 5428-5434. Zeng, Teng, et al. "Pesticide processing potential in prairie pothole porewaters."Environmental science & technology 45.16 (2011): 6814-6822. Zeng, Teng, Yu-Ping Chin, and William

  11. The use of Artificial Neural Networks for the selective detection of two organophosphate insecticides: chlorpyrifos and chlorfenvinfos.

    Science.gov (United States)

    Istamboulie, Georges; Cortina-Puig, Montserrat; Marty, Jean-Louis; Noguer, Thierry

    2009-07-15

    Amperometric acetylcholinesterase (AChE) biosensors have been developed to resolve mixtures of chlorpyrifos oxon (CPO) and chlorfenvinfos (CFV) pesticides. Three different biosensors were built using the wild type from electric eel (EE), the genetically modified Drosophila melanogaster AChE B394 and B394 co-immobilized with a phosphotriesterase (PTE). Artificial Neural Networks (ANNs) were used to model the combined response of the two pesticides. Specifically two different ANNs were constructed. The first one was used to model the combined response of B394+PTE and EE biosensors and was applied when the concentration of CPO was high and the other, modelling the combined response of B394+PTE and B394 biosensors, was applied with low concentrations of CPO. In both cases, good prediction ability was obtained with correlation coefficients better than 0.986 when the obtained values were compared with those expected for a set of six external test samples not used for training.

  12. Oxone/Fe[superscript 2+] Degradation of Food Dyes: Demonstration of Catalyst-Like Behavior and Kinetic Separation of Color

    Science.gov (United States)

    Nalliah, Ruth E.

    2015-01-01

    A demonstration of the degradation of food coloring dyes by oxidation via the Fenton reaction can be substituted with a simpler demonstration using the oxidant oxone with iron(II) ions as an activator. The addition of small amounts of solid oxone and iron(II) sulfate to solutions containing mixtures of food coloring results in successive…

  13. Comparative effects of chlorpyrifos in wild type and cannabinoid Cb1 receptor knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey, E-mail: carey.pope@okstate.edu

    2011-11-15

    Endocannabinoids (eCBs) modulate neurotransmission by inhibiting the release of a variety of neurotransmitters. The cannabinoid receptor agonist WIN 55.212-2 (WIN) can modulate organophosphorus (OP) anticholinesterase toxicity in rats, presumably by inhibiting acetylcholine (ACh) release. Some OP anticholinesterases also inhibit eCB-degrading enzymes. We studied the effects of the OP insecticide chlorpyrifos (CPF) on cholinergic signs of toxicity, cholinesterase activity and ACh release in tissues from wild type (+/+) and cannabinoid CB1 receptor knockout (-/-) mice. Mice of both genotypes (n = 5-6/treatment group) were challenged with CPF (300 mg/kg, 2 ml/kg in peanut oil, sc) and evaluated for functional and neurochemical changes. Both genotypes exhibited similar cholinergic signs and cholinesterase inhibition (82-95% at 48 h after dosing) in cortex, cerebellum and heart. WIN reduced depolarization-induced ACh release in vitro in hippocampal slices from wild type mice, but had no effect in hippocampal slices from knockouts or in striatal slices from either genotype. Chlorpyrifos oxon (CPO, 100 {mu}M) reduced release in hippocampal slices from both genotypes in vitro, but with a greater reduction in tissues from wild types (21% vs 12%). CPO had no significant in vitro effect on ACh release in striatum. CPF reduced ACh release in hippocampus from both genotypes ex vivo, but reduction was again significantly greater in tissues from wild types (52% vs 36%). In striatum, CPF led to a similar reduction (20-23%) in tissues from both genotypes. Thus, while CB1 deletion in mice had little influence on the expression of acute toxicity following CPF, CPF- or CPO-induced changes in ACh release appeared sensitive to modulation by CB1-mediated eCB signaling in a brain-regional manner. -- Highlights: Black-Right-Pointing-Pointer C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. Black-Right-Pointing-Pointer Wild type and

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-03-01

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

  15. [Photochemical degradation of chlorpyrifos in water].

    Science.gov (United States)

    Wu, Xiangwei; Hua, Rimao; Tang, Feng; Li, Xuede; Cao, Haiqun; Yue, Yongde

    2006-07-01

    In this paper, the effects of different light sources, temperature, pH, and water quality on the photochemical degradation of clilorpyrifos in water were examined under natural and simulated solar irradiation. The results showed that the photochemical degradation of chlorpyrifos in water followed the first order reaction, and its half-life was 0.62, 6.92, 19.74 and 22.50 h under high pressure mercury lamp (HPML), xenon lamp (XL), ultraviolet lamp (UV), and sunlight (SL) irradiation, respectively. Temperature had a significant effect on the degradation rate of chlorpyrifos, which was increased with increasing temperature and reached the maximum at 35 degrees C. The degradation rate of chlorpyrifos was stable both in acid and in neutral buffer solution, but enhanced in alkaline buffer solution. Water quality also had a significant effect, with a decreasing degradation rate of chlorpyrifos in the sequence of distilled water > tap water > river water > lake wate > paddy water.

  16. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides. PMID:26837064

  17. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

  18. Dissipation of chlorpyrifos on pakchoi inside and outside greenhouse

    Institute of Scientific and Technical Information of China (English)

    YU Yun-long; FANG Hua; WANG Xiao; YU Jing-quan; FAN De-fang

    2005-01-01

    The dissipation of chlorpyrifos on pakchoi inside and outside greenhouse was studied. The decline curve of chlorpyrifos on pakchoi could be described as first-order kinetic. The experimental data showed that both the hermetic environment of greenhouse and season affected dissipation rates of chlorpyrifos on pakchoi. Chlorpyrifos declined faster outside greenhouse than inside greenhouse.Chlorpyrifos residues at pre-harvest time were below the maximum residue limits (MRLs) fixed in China, whereas the values inside greenhouse were higher than those outside greenhouse by almost 50%. The recommended pre-harvest time established under conditions of open field might not always fit to greenhouse production.

  19. Variation characteristics of chlorpyrifos in nonsterile wetland plant hydroponic system.

    Science.gov (United States)

    Wang, Chuan; Zhou, Qiaohong; Zhang, Liping; Zhang, Yan; Xiao, Enrong; Wu, Zhenbin

    2013-01-01

    Six wetland plants were investigated for their effect on the degradation characteristics of chlorpyrifos in nonsterile hydroponic system at constant temperature of 28 degrees C. The results showed that the removal rates of chlorpyrifos in the water of plant systems were 1.26-5.56% higher than that in the control without plants. Scirpus validus and Typha angustifolia were better than other hygrophytes in elimination of chlorpyrifos. The removal rates of the two systems were up to 88%. Plants of acaulescent group had an advantage over caulescent group in removing chlorpyrifos. Phytoaccumulation of chlorpyrifos was observed, and the order of chlorpyrifos concentration in different plant tissues was root > stem > leaf. It was also found that chlorpyrifos and its metabolite TCP decreased rapidly at the initial step of the experiment.

  20. Synthesis of o-Carboxyarylacrylic Acids by Room Temperature Oxidative Cleavage of Hydroxynaphthalenes and Higher Aromatics with Oxone.

    Science.gov (United States)

    Parida, Keshaba Nanda; Moorthy, Jarugu Narasimha

    2015-08-21

    A simple procedure for the synthesis of a variety of o-carboxyarylacrylic acids has been developed with Oxone (2KHSO5·KHSO4·K2SO4); the oxidation reaction involves the stirring of methoxy/hydroxy-substituted naphthalenes, phenanthrenes, anthracenes, etc. with Oxone in an acetonitrile-water mixture (1:1, v/v) at rt. Mechanistically, the reaction proceeds via initial oxidation of naphthalene to o-quinone, which undergoes cleavage to the corresponding o-carboxyarylacrylic acid. The higher aromatics are found to yield carboxymethyl lactones derived from the initially formed o-carboxyarylacrylic acids.

  1. Chlorpyrifos chronic toxicity in broilers and effect of vitamin C

    OpenAIRE

    A.M. Kammon; Singh, J; Banga, H. S.; Sodhi, S.; Brar, R. S.; Nagra, N.S.

    2011-01-01

    An experiment was conducted to study chlorpyrifos chronic toxicity in broilers and the protective effect of vitamin C. Oral administration of 0.8 mg/kg body weight (bw) (1/50 LD50) chlorpyrifos (Radar®), produced mild diarrhea and gross lesions comprised of paleness, flaccid consistency and slightly enlargement of liver. Histopathologically, chlorpyrifos produced degenerative changes in various organs. Oral administration of 100 mg/kg bw vitamin C partially ameliorated the degenerative change...

  2. Human exposure and risk from indoor use of chlorpyrifos.

    OpenAIRE

    Gibson, J.E.; Peterson, R K; Shurdut, B A

    1998-01-01

    The toxicity, exposure, and risk from chlorpyrifos are briefly discussed in juxtaposition with two recent articles in Environmental Health Perspectives concerning potential exposures to children. In studies conducted according to EPA guidelines, chlorpyrifos has been shown not to be mutagenic, carcinogenic, or teratogenic, nor does it adversely affect reproduction. Chlorpyrifos toxicity does not occur in the absence of significant cholinesterase inhibition. If exposures are less than those th...

  3. Oral intake of hydrogen-rich water ameliorated chlorpyrifos-induced neurotoxicity in rats

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tingting; Zhao, Ling; Liu, Mengyu; Xie, Fei; Ma, Xuemei, E-mail: xmma@bjut.edu.cn; Zhao, Pengxiang; Liu, Yunqi; Li, Jiala; Wang, Minglian; Yang, Zhaona; Zhang, Yutong

    2014-10-01

    Chronic exposure to low-levels of organophosphate (OP) compounds, such as chlorpyrifos (CPF), induces oxidative stress and could be related to neurological disorders. Hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. We explore whether intake of hydrogen-rich water (HRW) can protect Wistar rats from CPF-induced neurotoxicity. Rats were gavaged daily with 6.75 mg/kg body weight (1/20 LD{sub 50}) of CPF and given HRW by oral intake. Nissl staining and electron microscopy results indicated that HRW intake had protective effects on the CPF-induced damage of hippocampal neurons and neuronal mitochondria. Immunostaining results showed that the increased glial fibrillary acidic protein (GFAP) expression in astrocytes induced by CPF exposure can be ameliorated by HRW intake. Moreover, HRW intake also attenuated CPF-induced oxidative stress as evidenced by enhanced level of MDA, accompanied by an increase in GSH level and SOD and CAT activity. Acetylcholinesterase (AChE) activity tests showed significant decrease in brain AChE activity after CPF exposure, and this effect can be ameliorated by HRW intake. An in vitro study demonstrated that AChE activity was more intense in HRW than in normal water with or without chlorpyrifos-oxon (CPO), the metabolically-activated form of CPF. These observations suggest that HRW intake can protect rats from CPF-induced neurotoxicity, and the protective effects of hydrogen may be mediated by regulating the oxidant and antioxidant status of rats. Furthermore, this work defines a novel mechanism of biological activity of hydrogen by directly increasing the AChE activity. - Highlights: • Hydrogen molecules protect rats from CPF-induced damage of hippocampal neurons. • The increased GFAP expression induced by CPF can also be ameliorated by hydrogen. • Hydrogen molecules attenuated the increase in CPF-induced oxidative stress. • Hydrogen molecules attenuated AChE inhibition in vivo

  4. 77 FR 56115 - Safety Zone for Fireworks Display, Potomac River, National Harbor Access Channel; Oxon Hill, MD

    Science.gov (United States)

    2012-09-12

    ...: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed..., adjacent to the Gaylord National Resort Hotel, at Oxon Hill in Prince Georges County, Maryland, scheduled... of Executive Order 13563. The Office of Management and Budget has not reviewed it under those...

  5. Oxidation of Borneol to Camphor Using Oxone and Catalytic Sodium Chloride: A Green Experiment for the Undergraduate Organic Chemistry Laboratory

    Science.gov (United States)

    Lang, Patrick T.; Harned, Andrew M.; Wissinger, Jane E.

    2011-01-01

    A new green oxidation procedure was developed for the undergraduate organic teaching laboratories using Oxone and a catalytic quantity of sodium chloride for the conversion of borneol to camphor. This simple 1 h, room temperature reaction afforded high quality and yield of product, was environmentally friendly, and produced negligible quantities…

  6. Chlorpyrifos toxicity in fish: A Review

    OpenAIRE

    Nobonita Deb; Suchismita Das

    2013-01-01

    Chlorpyrifos (CPF) is a broad spectrum organophosphate insecticide (OP) which is commercially used for more than a decade to control insect pest. It is the second largest selling OP and found to be more toxic to fish than organochlorine compounds. CPF passes via air drift or surface runoff into natural waters, where it is accumulated in different organisms living in water, especially in fish, thus making it vulnerable to several prominent effects. CPF is known to inhibit acetylcholinesterase,...

  7. Efficient elimination of caffeine from water using Oxone activated by a magnetic and recyclable cobalt/carbon nanocomposite derived from ZIF-67.

    Science.gov (United States)

    Lin, Kun-Yi Andrew; Chen, Bo-Chau

    2016-02-28

    To eliminate caffeine, one of the most common pharmaceuticals and personal care products, from water, Oxone (peroxymonosulfate salt) was proposed to degrade it. To accelerate the generation of sulfate radicals from Oxone, a magnetic cobalt/carbon nanocomposite (CCN) was prepared from a one-step carbonization of a cobalt-based Zeolitic Imidazolate Framework (ZIF-67). The resultant CCN exhibits immobilized cobalt and increased porosity, and can be magnetically manipulated. These characteristics make CCN a promising heterogeneous catalyst to activate Oxone for caffeine degradation. Factors affecting the caffeine degradation were investigated, including CCN loading, Oxone dosage, temperature, pH, surfactants, salts and inhibitors. A higher CCN loading, Oxone dosage and temperature greatly improved the caffeine degradation by CCN-activated Oxone. Acidic conditions were also preferable over basic conditions for caffeine degradation. The addition of cetyltrimethylammonium bromide (CTAB) and NaCl both significantly hindered caffeine degradation because bromide from CTAB and chloride from NaCl scavenged sulfate radicals. Based on the effects of inhibitors (i.e., methanol and tert-butyl alcohol), the caffeine degradation by CCN-activated Oxone was considered to primarily involve sulfate radicals and, less commonly, hydroxyl radicals. The intermediates generated during the caffeine degradation were analyzed using GC-MS and a possible degradation pathway was proposed. CCN was also able to activate Oxone for caffeine degradation for multiple cycles without changing its catalytic activity. These features reveal that CCN is an effective and promising catalyst for the activation of Oxone for the degradation of caffeine. PMID:26804184

  8. Irradiation degradation of chlorpyrifos in water solution and asparagus

    International Nuclear Information System (INIS)

    In order to seek an effective technique to degrade chlorpyrifos residue, chlorpyrifos water solution and asparagus containing chlorpyrifos as testing materials were irradiated by 60Co γ-rays and their degradation rate were determined and compared. The results show the degradation rate in water-solution increases with irradiation dose in the range of 0 and 12 kGy, and it reached 95.5% at 4 kGy. The degradation rate of chlorpyrifos in asparagus is low and comes to the maximum of 30.0% when the dose is 8 kGy. Further study indicates that vitamin C, violaquercitrin and total sugar inhibit the irradiation degradation of chlorpyrifos in asparagus. (authors)

  9. Chlorpyrifos toxicity in fish: A Review

    Directory of Open Access Journals (Sweden)

    Nobonita Deb

    2013-04-01

    Full Text Available Chlorpyrifos (CPF is a broad spectrum organophosphate insecticide (OP which is commercially used for more than a decade to control insect pest. It is the second largest selling OP and found to be more toxic to fish than organochlorine compounds. CPF passes via air drift or surface runoff into natural waters, where it is accumulated in different organisms living in water, especially in fish, thus making it vulnerable to several prominent effects. CPF is known to inhibit acetylcholinesterase, cause behavioural, neurological, oxidative, histopathological, endocrine and other effects at low doses. The present study reviews the various effects of CPF in fish

  10. Differential sensitivity of plasma carboxylesterase-null mice to parathion, chlorpyrifos and chlorpyrifos oxon, but not to diazinon, dichlorvos, diisopropylfluorophosphate, cresyl saligenin phosphate, cyclosarin thiocholine, tabun thiocholine, and carbofuran

    OpenAIRE

    Duysen, Ellen G.; Cashman, John R.; Schopfer, Lawrence M.; Nachon, Florian; Masson, Patrick; Lockridge, Oksana

    2011-01-01

    Mouse blood contains four esterases that detoxify organophosphorus compounds: carboxylesterase, butyrylcholinesterase, acetylcholinesterase, and paraoxonase-1. In contrast human blood contains the latter three enzymes but not carboxylesterase. Organophosphorus compound toxicity is due to inhibition of acetylcholinesterase. Symptoms of intoxication appear after approximately 50% of the acetylcholinesterase is inhibited. However, complete inhibition of carboxylesterase and butyrylcholinesterase...

  11. Modifying Effects of Vitamin E on Chlorpyrifos Toxicity in Atlantic Salmon

    OpenAIRE

    Olsvik, Pål A; Berntssen, Marc H. G.; Liv Søfteland

    2015-01-01

    The aim of this study was to elucidate how vitamin E (alpha tocopherol) may ameliorate the toxicity of the pesticide chlorpyrifos in Atlantic salmon. Freshly isolated hepatocytes were exposed to vitamin E, chlorpyrifos or a combination of vitamin E and chlorpyrifos (all 100 μM). Transcriptomics (RNA-seq) and metabolomics were used to screen for effects of vitamin E and chlorpyrifos. By introducing vitamin E, the number of upregulated transcripts induced by chlorpyrifos exposure was reduced fr...

  12. Effect of potassium monopersulfate (oxone) and operating parameters on sonochemical degradation of cationic dye in an aqueous solution.

    Science.gov (United States)

    Soumia, Fassi; Petrier, Christian

    2016-09-01

    In this study, removal of Cresol Red (CR), a cationic triphenylmethane dye, by 300kHz ultrasound was investigated. The effect of additive such as potassium monopersulfate (oxone) was studied. Additionally, sonolytic degradation of CR was investigated at varying power and initial pH. RC can be readily eliminated by the ultrasound process. The obtained results showed that. Sonochemical degradation of CR was strongly affected by ultrasonic power and pH. The degradation rate of the dye increased substantially with increasing ultrasonic power in the range of 20-80W. This improvement could be explained by the increase in the number of active cavitation bubbles. The significant degradation was achieved in acidic conditions (pH=2) where the color removal was 99% higher than those observed in higher pH aqueous solutions. The ultrasonic degradation of dye was enhanced by potassium monopersulfate (oxone) addition. It was found that the degradation of the dye was accelerated with increased concentrations of oxone for a reaction time of 75min. PMID:27150780

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

    Institute of Scientific and Technical Information of China (English)

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

    2004-01-01

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

  14. Chlorpyrifos chronic toxicity in broilers and effect of vitamin C

    Directory of Open Access Journals (Sweden)

    A.M. Kammon

    2011-02-01

    Full Text Available An experiment was conducted to study chlorpyrifos chronic toxicity in broilers and the protective effect of vitamin C. Oral administration of 0.8 mg/kg body weight (bw (1/50 LD50 chlorpyrifos (Radar®, produced mild diarrhea and gross lesions comprised of paleness, flaccid consistency and slightly enlargement of liver. Histopathologically, chlorpyrifos produced degenerative changes in various organs. Oral administration of 100 mg/kg bw vitamin C partially ameliorated the degenerative changes in kidney and heart. There was insignificant alteration in biochemical and haematological profiles. It is concluded that supplementation of vitamin C reduced the severity of lesions induced by chronic chlorpyrifos toxicity in broilers.

  15. DOES THYROID DISRUPTION CONTRIBUTE TO THE DEVELOPMENTAL NEUROTOXICITY OF CHLORPYRIFOS?

    OpenAIRE

    Slotkin, Theodore A.; Cooper, Ellen M.; Stapleton, Heather M.; Seidler, Frederic J

    2013-01-01

    Although organophosphate pesticides are not usually characterized as “endocrine disruptors,” recent work points to potential, long-term reductions of circulating thyroid hormones after developmental exposures to chlorpyrifos that are devoid of observable toxicity. We administered chlorpyrifos to developing rats on gestational days 17–20 or postnatal days 1–4, regimens that produce distinctly different, sex-selective effects on neurobehavioral performance. The prenatal regimen produced a small...

  16. Biodegradation of Chlorpyrifos by Pseudomonas Resinovarans Strain AST2.2 Isolated from Enriched Cultures.

    Directory of Open Access Journals (Sweden)

    Anish Sharma*,

    2016-04-01

    Full Text Available A bacterial strain AST2.2 with chlorpyrifos degrading ability was isolated by enrichment technique from apple orchard soil with previous history of chlorpyrifos use. Based on the morphological, biochemical tests and 16S rRNA sequence analysis, AST2.2 strain was identified as Pseudomonas resinovarans. The strain AST2.2 utilized chlorpyrifos as the sole source of carbon and energy. This strain exhibited growth upto 400mg/l concentration of chlorpyrifos and exhibited high extracellular organophosphorus hydrolase (OPH activity. Gas chromatography-flame ionization detector (GC-FID studies revealed that Pseudomonas resinovarans AST2.2 degraded 43.90 % of chlorpyrifos (400 mg/l within 96 hrs. Intermediates of chlorpyrifos degradation were identified using GC-MS. This strain have potential to degrade chlorpyrifos and thus can be used for bioremediation and ecological restoration of sites contaminated with chlorpyrifos.

  17. Chlorpyrifos-induced toxicity in Duttaphrynus melanostictus (Schneider 1799) larvae.

    Science.gov (United States)

    Wijesinghe, M R; Bandara, M G D K; Ratnasooriya, W D; Lakraj, G P

    2011-05-01

    This study investigates the effects of continuous exposure to a widely used organophosphate pesticide, chlorpyrifos, on survival, growth, development, and activity of larvae of the Asian common toad, Duttaphrynus melanostictus Schneider 1799. Larvae were continuously exposed to six different concentrations (1-1,500 μg l(-1)) of commercial-grade chlorpyrifos for 14 days and monitored for 1 additional week. Chlorpyrifos at ≥1,000 μg l(-1) caused significantly high and dose-dependent mortality, and the weekly LC50(7 day-21 day) values ranged from 3,003 to 462 μg l(-1). Larvae surviving exposure to ≥500 μg l(-1) chlorpyrifos showed significant growth impairment, delays in metamorphosis, and decreased swimming activity. Tail abnormalities were the most common morphologic deformity at concentrations of 1,000 and 1,500 μg l(-1) chlorpyrifos. The findings of the present study highlight the need to recognize the potential risk that agrochemicals pose to amphibians inhabiting agricultural landscapes in Sri Lanka and other Asian countries. PMID:20669016

  18. Examining the joint toxicity of chlorpyrifos and atrazine in the aquatic species: Lepomis macrochirus, Pimephales promelas and Chironomus tentans

    Energy Technology Data Exchange (ETDEWEB)

    Tyler Mehler, W.; Schuler, Lance J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States); Lydy, Michael J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States)], E-mail: mlydy@siu.edu

    2008-03-15

    The joint toxicity of chlorpyrifos and atrazine was compared to that of chlorpyrifos alone to discern any greater than additive response using both acute toxicity testing and whole-body residue analysis. In addition, acetylcholinesterase (AChE) inhibition and biotransformation were investigated to evaluate the toxic mode of action of chlorpyrifos in the presence of atrazine. The joint toxicity of atrazine and chlorpyrifos exhibited no significant difference in Lepomis macrochirus compared to chlorpyrifos alone; while studies performed with Pimephales promelas and Chironomus tentans, did show significant differences. AChE activity and biotransformation showed no significant differences between the joint toxicity of atrazine and chlorpyrifos and that of chlorpyrifos alone. From the data collected, the combination of atrazine and chlorpyrifos pose little additional risk than that of chlorpyrifos alone to the tested fish species. - The joint toxicity between atrazine and chlorpyrifos caused greater than additive responses in invertebrates, but the interactions in vertebrates was less pronounced.

  19. CoFe2O4 magnetic nanoparticles as a highly active heterogeneous catalyst of oxone for the degradation of diclofenac in water

    International Nuclear Information System (INIS)

    Highlights: • CoFe2O4 MNPs tested as heterogeneous catalyst for the activation of oxone. • The catalytic performance was typically affected by several key operating parameters. • The catalyst exhibited good stability and easily recovered with excellent reusability. • Degradation pathway was proposed according to the results of LC-MS/MS analysis. -- Abstract: A magnetic nanoscaled catalyst cobalt ferrite (CoFe2O4) was successfully prepared and used for the activation of oxone to generate sulfate radicals for the degradation of diclofenac. The catalyst was characterized by transmission electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The effects of calcination temperature, initial pH, catalyst and oxone dosage on the degradation efficiency were investigated. Results demonstrated that CoFe2O4-300 exhibited the best catalytic performance and almost complete removal of diclofenac was obtained in 15 min. The degradation efficiency increased with initial pH decreasing in the pH range of 5–9. The increase of catalyst and oxone dosage both had the positive effect on the degradation of diclofenac. Moreover, CoFe2O4 could retain high degradation efficiency even after being reused for five cycles. Finally, the major diclofenac degradation intermediates were identified and the primary degradation pathways were proposed

  20. Dissipation of 14C chlorpyrifos in the rhizosphere of rice

    International Nuclear Information System (INIS)

    The root exudates from the plants contribute to the biodegradation of insecticides. Although, different mechanisms have been proposed, there is no clear elucidation of any mechanism. This study investigates the dissipation of an organophosphorus insecticide, chlorpyrifos in the rhizospheric soil planted with rice plant. Two sets of experimental tanks were maintained with or without plants using soil spiked with 1 mg kg-1 and 10 mg kg-1 of chlorpyrifos. Experiment was conducted for 180 days till the rice plant starts bearing seeds. The 14C activity decreased rapidly in the rhizospheric soil as compare to the non-rhizospheric soil. The total culturable microflora were higher in the rhizospheric than the non-rhizospheric soil. The plant extract had given few counts indicating some negligible amount of chlorpyrifos uptake. The 14C activity in the water was disappeared after 30 days. It was observed that very low amount of residue persisted in soil. This studies revealed that the plants play an important role in the dissipation of the chlorpyrifos from the rice flooded rhizospheric soil. (author)

  1. Structural and metabolic responses of microbial community to sewage-borne chlorpyrifos in constructed wetlands.

    Science.gov (United States)

    Zhang, Dan; Wang, Chuan; Zhang, Liping; Xu, Dong; Liu, Biyun; Zhou, Qiaohong; Wu, Zhenbin

    2016-06-01

    Long-term use of chlorpyrifos poses a potential threat to the environment that cannot be ignored, yet little is known about the succession of substrate microbial communities in constructed wetlands (CWs) under chlorpyrifos stress. Six pilot-scale CW systems receiving artificial wastewater containing 1mg/L chlorpyrifos were established to investigate the effects of chlorpyrifos and wetland vegetation on the microbial metabolism pattern of carbon sources and community structure, using BIOLOG and denaturing gradient gel electrophoresis (DGGE) approaches. Based on our samples, BIOLOG showed that Shannon diversity (H') and richness (S) values distinctly increased after 30days when chlorpyrifos was added. At the same time, differences between the vegetated and the non-vegetated systems disappeared. DGGE profiles indicated that H' and S had no significant differences among four different treatments. The effect of chlorpyrifos on the microbial community was mainly reflected at the physiological level. Principal component analysis (PCA) of both BIOLOG and DGGE showed that added chlorpyrifos made a difference on test results. Meanwhile, there was no difference between the vegetation and no-vegetation treatments after addition of chlorpyrifos at the physiological level. Moreover, the vegetation had no significant effect on the microbial community at the genetic level. Comparisons were made between bacteria in this experiment and other known chlorpyrifos-degrading bacteria. The potential chlorpyrifos-degrading ability of bacteria in situ may be considerable. PMID:27266297

  2. Modifying effects of vitamin E on chlorpyrifos toxicity in atlantic salmon.

    Directory of Open Access Journals (Sweden)

    Pål A Olsvik

    Full Text Available The aim of this study was to elucidate how vitamin E (alpha tocopherol may ameliorate the toxicity of the pesticide chlorpyrifos in Atlantic salmon. Freshly isolated hepatocytes were exposed to vitamin E, chlorpyrifos or a combination of vitamin E and chlorpyrifos (all 100 μM. Transcriptomics (RNA-seq and metabolomics were used to screen for effects of vitamin E and chlorpyrifos. By introducing vitamin E, the number of upregulated transcripts induced by chlorpyrifos exposure was reduced from 941 to 626, while the number of downregulated transcripts was reduced from 901 to 742 compared to the control. Adding only vitamin E had no effect on the transcriptome. Jak-STAT signaling was the most significantly affected pathway by chlorpyrifos treatment according to the transcriptomics data. The metabolomics data showed that accumulation of multiple long chain fatty acids and dipeptides and amino acids in chlorpyrifos treated cells was partially alleviated by vitamin E treatment. Significant interaction effects between chlorpyrifos and vitamin E were seen for 15 metabolites, including 12 dipeptides. The antioxidant had relatively modest effects on chlorpyrifos-induced oxidative stress. By combining the two data sets, the study suggests that vitamin E supplementation prevents uptake and accumulation of fatty acids, and counteracts inhibited carbohydrate metabolism. Overall, this study shows that vitamin E only to a moderate degree modifies chlorpyrifos toxicity in Atlantic salmon liver cells.

  3. Genotoxicity of Chlorpyrifos and the Antimutagenic Role of Lettuce Leaves in Male Mice

    OpenAIRE

    Kamilia Badrakhan Abdelaziz; Aida Ibrahim El Makawy; Ali Zain El-Abidin Abd Elsalam; Ahmed Mohamed Darwish

    2010-01-01

    Chlorpyrifos [O O-diethyl-O-(3 5 6-trichloro-2-pyridyl)-phosphorothioate] is one of the most widelyused organophosphate insecticides. Previous studies proved that chlorpyrifos, at different doses,induced genotoxicity. In Egyptian foods, the residual levels of pesticides are often higher than thosefound in developed country ones. So the aim of this research was to evaluate the genotoxicity of theinsecticide chlorpyrifos at doses equal to its maximum residue limit (MRL) in the leafy vegetables,...

  4. Developmental Exposure of Rats to Chlorpyrifos Elicits Sex-Selective Hyperlipidemia and Hyperinsulinemia in Adulthood

    OpenAIRE

    Slotkin, Theodore A.; Kathleen K Brown; Seidler, Frederic J

    2005-01-01

    Developmental exposure to chlorpyrifos alters cell signaling both in the brain and in peripheral tissues, affecting the responses to a variety of neurotransmitters and hormones. We administered 1 mg/kg/day chlorpyrifos to rats on postnatal days 1–4, a regimen below the threshold for systemic toxicity. When tested in adulthood, chlorpyrifos-exposed animals displayed elevations in plasma cholesterol and triglycerides, without underlying alterations in nonesterified free fatty acids and glycerol...

  5. Soil bacteria showing a potential of chlorpyrifos degradation and plant growth enhancement

    OpenAIRE

    Akbar, Shamsa; Sultan, Sikander

    2016-01-01

    Background Since 1960s, the organophosphate pesticide chlorpyrifos has been widely used for the purpose of pest control. However, given its persistence and toxicity towards life forms, the elimination of chlorpyrifos from contaminated sites has become an urgent issue. For this process bioremediation is the method of choice. Results Two bacterial strains, JCp4 and FCp1, exhibiting chlorpyrifos-degradation potential were isolated from pesticide contaminated agricultural fields. These isolates w...

  6. Mortality among Pesticide Applicators Exposed to Chlorpyrifos in the Agricultural Health Study

    OpenAIRE

    Lee, Won Jin; Alavanja, Michael C.R.; Hoppin, Jane A; Rusiecki, Jennifer A.; Kamel, Freya; Blair, Aaron; Sandler, Dale P.

    2007-01-01

    Background Chlorpyrifos is one of the most widely used organophosphate insecticides in the United States. Although the toxicity of chlorpyrifos has been extensively studied in animals, the epidemiologic data are limited. Objective To evaluate whether agricultural chlorpyrifos exposure was associated with mortality, we examined deaths among pesticide applicators in the Agricultural Health Study, a prospective study of licensed pesticide applicators in Iowa and North Carolina. Methods A total o...

  7. Vitamin C Attenuates Chronic Chlorpyrifos-induced Alteration of Neurobehavioral Parameters in Wistar Rats

    OpenAIRE

    Suleiman F. Ambali; Joseph O. Ayo

    2012-01-01

    Background: Oxidative stress is one of the molecular mechanisms in chlorpyrifos toxicity. The present study was designed to evaluate the attenuating effect of vitamin C on chlorpyrifos-induced alteration of neurobehavioral performance and the role of muscle acetylchloinesterase (AChE), glycogen and lipoperoxidation in the accomplishment of this task. Materials and Methods: Male rats were randomly assigned into 4 groups with the following regimens: soya oil (S/oil), vitamin C (VC), chlorpyrifo...

  8. [Thermodynamics adsorption and its influencing factors of chlorpyrifos and triazophos on the bentonite and humus].

    Science.gov (United States)

    Zhu, Li-Jun; Zhang, Wei; Zhang, Jin-Chi; Zai, De-Xin; Zhao, Rong

    2010-11-01

    The adsorption of chlorpyrifos and triazophos on bentonite and humus was investigated by using the equilibrium oscillometry. The adsorption capacity of chlorpyrifos and triazophos on humus was great higher than bentonite at the same concentration. Equilibrium data of Langmuir, Freundlich isotherms showed significant relationship to the adsorption of chlorpyrifos and triazophos on humus (chlorpyrifos: R2 0.996 4, 0.996 3; triazophos: R2 0.998 9, 0.992 4). Langmuir isotherm was the best for chlorpyrifos and triazophos on bentonite (chlorpyrifos: R2 = 0.995 7, triazophos: R2 = 0.998 9). The pH value, adsorption equilibrium time and temperature were the main factors affecting adsorption of chlorpyrifos and triazophos on bentonite and humus. The adsorption equilibrium time on mixed adsorbent was 12h for chlorpyrifos and 6h for triazophos respectively. The mass ratio of humus and bentonite was 12% and 14% respectively, the adsorption of chlorpyrifos and triazophos was the stronglest and tended to saturation. At different temperatures by calculating the thermodynamic parameters deltaG, deltaH and deltaS, confirmed that the adsorption reaction was a spontaneous exothermic process theoretically. The adsorption was the best when the pH value was 6.0 and the temperature was 15 degrees C.

  9. Complete biodegradation of chlorpyrifos by engineered Pseudomonas putida cells expressing surface-immobilized laccases.

    Science.gov (United States)

    Liu, Jin; Tan, Luming; Wang, Jing; Wang, Zhiyong; Ni, Hong; Li, Lin

    2016-08-01

    The long-term abuse use of chlorpyrifos-like pesticides in agriculture and horticulture has resulted in significant soil or water contamination and a worldwide ecosystem threat. In this study, the ability of a solvent-tolerant bacterium, Pseudomonas putida MB285, with surface-displayed bacterial laccase, to biodegrade chlorpyrifos was investigated. The results of compositional analyses of the degraded products demonstrate that the engineered MB285 was capable of completely eliminating chlorpyrifos via direct biodegradation, as determined by high-performance liquid chromatography and gas chromatography-mass spectrometry assays. Two intermediate metabolites, namely 3,5,6-trichloro-2-pyridinol (TCP) and diethyl phosphate, were temporarily detectable, verifying the joint and stepwise degradation of chlorpyrifos by surface laccases and certain cellular enzymes, whereas the purified free laccase incompletely degraded chlorpyrifos into TCP. The degradation reaction can be conducted over a wide range of pH values (2-7) and temperatures (5-55 °C) without the need for Cu(2+). Bioassays using Caenorhabditis elegans as an indicator organism demonstrated that the medium was completely detoxified of chlorpyrifos by degradation. Moreover, the engineered cells exhibited a high capacity of repeated degradation and good performance in continuous degradation cycles, as well as a high capacity to degrade real effluents containing chlorpyrifos. Therefore, the developed system exhibited a high degradation capacity and performance and constitutes an improved approach to address chlorpyrifos contamination in chlorpyrifos-remediation practice. PMID:27231878

  10. [Biodegradation mechanism of DDT and chlorpyrifos using molecular simulation].

    Science.gov (United States)

    Lin, Yu-Zhen; Zeng, Guang-Ming; Zhang, Yu; Chen, Ming; Jiang, Min; Zhang, Jia-Chao; Lu, Lun-Hui; Liu, Li-Feng

    2012-03-01

    In order to explore the microscopic degradation mechanism of organic pesticides degrading enzymes, we used molecular docking method to investigate the binding modes of DDT to laccase and chlorpyrifos to organophosphorus hydrolase, and obtained the corresponding complex structures. According to the principle of minimum scoring, the results showed that the MolDock scores were -103.134 and -111.626, re-rank scores were -72.858 and -80.261, respectively. And we used LPC/CSU server search the interactions between organic pesticides and their degrading enzymes. Our results showed that hydrophobic interaction was the strongest contacts in DDT-laccase complex, and both hydrogen bonds and hydrophobic interactions were the strongest contacts when chlorpyrifos-organophosphorus hydrolase complex. The amino acid residues Tyr224 in laccase and Arg254 in organophosphorus hydrolase were detected to play significant roles in catalytic processes.

  11. Chlorpyrifos Detection by Piezoelectric Biosensor Based on Acetylcholinesterase Immobilization

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Acetylcholinesterase (AChE) was immobilized on multilayer films assembled by poly diallyldimethylammonium chloride (PDDA) and ι-carrageenan (IC) on silver-coated crystal electrode surfaces to detect the chlorpyrifos belonging to the organophosphates pesticide.Mass sensitive quartz crystal microbalance (QCM) was used to study the effect of AChE concentration and pH of phosphate buffer solution on immobilized acetylcholinesterase.The optimized conditions were as follows: pH was 6.0 which was near isoelectric ...

  12. Toxicity of chlorpyrifos on some marine cyanobacteria species

    International Nuclear Information System (INIS)

    Pakistan is an agricultural country and a wide variety of pesticides are used on its cropland. Pesticides pose serious threats to the natural ecosystem. In the present study cyanobacteria (blue green algae) were used to assess the ecotoxicological effect of chlorpyrifos (organophosphate pesticide). Cyanobacteria are the base of the food web providing food resource to consumers in higher trophic level. Cyanobacteria were isolated and purified from water samples collected from Manora channel. Fast growing cultures of cyanobacteria were used to assess the toxicity of test pesticide . The Light and Dark method was used to determine the primary production of the organisms. The acute toxicity of chlorpyrifos was determined by calculating IC/sub 50/ of the test organisms. The IC/sub 50/ was found to be 0.074, 0.013, 0.08 and 0.3 ppm for Synechocystis aquatilis, Komvophoron minutum, Gloeocapsa crepidinum and Gloeocapsa sanguinea when exposed to chlorpyrifos pesticide . Laboratory experiments with cyanobacteria have demonstrated that organophosphate pesticides are potent inhibitors of photosynthesis. (author)

  13. Sublethal toxicity of chlorpyrifos to salmonid olfaction after hypersaline acclimation.

    Science.gov (United States)

    Maryoung, Lindley A; Blunt, Brian; Tierney, Keith B; Schlenk, Daniel

    2015-04-01

    Salmonid habitats can be impacted by several environmental factors, such as salinization, which can also affect salmonid tolerance to anthropogenic stressors, such as pesticides. Previous studies have shown that hypersaline acclimation enhances the acute toxicity of certain organophosphate and carbamate pesticides to euryhaline fish; however, sublethal impacts have been far less studied. The current study aims to determine how hypersaline acclimation and exposure to the organophosphate chlorpyrifos (CPF) impact salmonid olfaction. Combined acclimation and exposure to CPF was shown to impact rainbow trout olfaction at the molecular, physiological, and behavioral levels. Concurrent exposure to hypersalinity and 0.5μg/L CPF upregulated four genes (chloride intracellular channel 4, G protein zgc:101761, calcium calmodulin dependent protein kinase II delta, and adrenergic alpha 2C receptor) that inhibit olfactory signal transduction. At the physiological level, hypersalinity and chlorpyrifos caused a decrease in sensory response to the amino acid l-serine and the bile salt taurocholic acid. Combined acclimation and exposure also negatively impacted behavior and reduced the avoidance of a predator cue (l-serine). Thus, acclimation to hypersaline conditions and exposure to environmentally relevant concentrations of chlorpyrifos caused an inhibition of olfactory signal transduction leading to a decreased response to odorants and impairment of olfactory mediated behaviors.

  14. Evaluation of antigout activity of Phyllanthus emblica fruit extracts on potassium oxonate-induced gout rat model

    Directory of Open Access Journals (Sweden)

    Vaidehi N. Sarvaiya

    2015-10-01

    Full Text Available Aim: The present study has been conducted to evaluate antigout activity of aqueous and alcoholic extracts of Phyllanthus emblica fruits following its 28 days repeated oral administration on potassium oxonate-induced gout rat model. Materials and Methods: The study was conducted on 42 male Sprague-Dawely rats dividing them in seven groups having six rats in each group. Groups I, II, and III served as vehicle control group, gout control group, and standard treatment control group, respectively. Rats of all the groups except vehicle control group were administered potassium oxonate at 250 mg/kg (IP, throughout the study period (28 days for induction of gout. Groups IV and V received aqueous extract of P. emblica at 200 and 400 mg/kg, and Groups VI and VII received alcoholic extract of P. emblica at 200 and 400 mg/kg (daily oral for 28 days. At the end of study, all the rats were subjected to blood collection; blood and serum sample were analyzed for hematological and biochemical parameters, respectively. After collection of blood samples on the 29th day, all the rats were sacrificed and subjected to post mortem examination to determine the presence or absence of gross and histopathological lesions in kidney tissues. Results: At the end of study, rats of gout control group showed increase in platelets counts, serum creatinine, uric acid, blood urea nitrogen (BUN, and xanthine oxidase (XO enzyme level along with alterations in kidney tissues as compared to vehicle control group. Gouty rats treated with aqueous and alcoholic extracts of P. emblica at 200 and 400 mg/kg body weight and standard treatment allopurinol at 5 mg/kg body weight showed reduction in platelets counts, serum creatinine, uric acid, BUN, and XO enzyme level along with significant improvements in histological structure of kidney as compared to rats of gout control group. Conclusion: Oral administration of aqueous and alcoholic extracts of P. emblica fruits for 28 days has shown

  15. Fate and effects of the insecticide chlorpyrifos in outdoor plankton-dominated microcosms in Thailand.

    NARCIS (Netherlands)

    Daam, M.A.; Crum, S.J.H.; Brink, van den P.J.; Nogueira, A.J.A.

    2008-01-01

    The fate and effects of the insecticide chlorpyrifos were studied in plankton-dominated, freshwater microcosms in Thailand. Disappearance rates of chlorpyrifos from the water column in the present study were similar to those in temperate regions. Insecticide accumulation in the sediment was relative

  16. Amygdala kindling in immature rats: proconvulsant effect of the organophosphate insecticide-chlorpyrifos.

    Science.gov (United States)

    Wurpel, J N; Hirt, P C; Bidanset, J H

    1993-01-01

    Administration of the organophosphate insecticide, chlorpyrifos to immature rats exerted a proconvulsant effect on seizures induced by kindling. Chlorpyrifos was administered to 16 or 17 day old rats in a dose range of 0.3 to 10 mg/kg, subcutaneously. Amygdala kindling was performed by stimulating the rats every 15 minutes to a total of 20 stimulations. Kindling occurred more rapidly in the chlorpyrifos treated rats than vehicle treated rats, the proconvulsant effect was dose-dependent. The proconvulsant effect of chlorpyrifos was more pronounced in the early stages of kindling, indicating a possible increase in local excitability of the amygdala in the presence of chlorpyrifos. Chlorpyrifos also reduced the after discharge threshold in the amygdala in a dose-dependent manner and increased the duration of after discharges elicited by electrical stimulus, indicating an increase in excitability of the amygdala. The effects of chlorpyrifos on kindling were additive with xylene: the proconvulsant effect in the early stages of kindling was greatly enhanced by xylene. Xylene, administered alone as a 0.2% solution, reduced the after discharge threshold of the amygdala, increased the after discharge duration and increased the rate of kindling. These experiments demonstrate a proconvulsant effect of chlorpyrifos in amygdala kindling and this proconvulsant action is additive with xylene.

  17. Binding and detoxification of chlorpyrifos by lactic acid bacteria on rice straw silage fermentation.

    Science.gov (United States)

    Wang, Yan-Su; Wu, Tian-Hao; Yang, Yao; Zhu, Cen-Ling; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-01-01

    This investigation examined the reduction of pesticide residues on straw inoculated with lactic acid bacteria (LAB) during ensiling. Lactobacillus casei WYS3 was isolated from rice straw that contained pesticide residues. Non-sterilized rice straw, which was inoculated with L. casei WYS3, showed increased removal of chlorpyrifos after ensiling, compared with rice straw that was not inoculated with L. casei WYS3 or sterilized rice straw. In pure culture, these strains can bind chlorpyrifos as indicated by high-performance liquid chromatography analysis. Viable L. casei WYS3 was shown to bind 33.3-42% of exogenously added chlorpyrifos. These results are similar to those of acid-treated cells but less than those of heat-treated cells, which were found to bind 32.0% and 77.2% of the added chlorpyrifos respectively. Furthermore, gas chromatography-mass spectrometry analysis determined that L. casei WYS3 detoxified chlorpyrifos via P-O-C cleavage. Real-time polymerized chain reaction analysis determined that organophosphorus hydrolase gene expression tripled after the addition of chlorpyrifos to LAB cultures, compared with the control group (without chlorpyrifos). This paper highlights the potential use of LAB starter cultures for the detoxification and removal of chlorpyrifos residues in the environment.

  18. Binding and detoxification of chlorpyrifos by lactic acid bacteria on rice straw silage fermentation.

    Science.gov (United States)

    Wang, Yan-Su; Wu, Tian-Hao; Yang, Yao; Zhu, Cen-Ling; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-01-01

    This investigation examined the reduction of pesticide residues on straw inoculated with lactic acid bacteria (LAB) during ensiling. Lactobacillus casei WYS3 was isolated from rice straw that contained pesticide residues. Non-sterilized rice straw, which was inoculated with L. casei WYS3, showed increased removal of chlorpyrifos after ensiling, compared with rice straw that was not inoculated with L. casei WYS3 or sterilized rice straw. In pure culture, these strains can bind chlorpyrifos as indicated by high-performance liquid chromatography analysis. Viable L. casei WYS3 was shown to bind 33.3-42% of exogenously added chlorpyrifos. These results are similar to those of acid-treated cells but less than those of heat-treated cells, which were found to bind 32.0% and 77.2% of the added chlorpyrifos respectively. Furthermore, gas chromatography-mass spectrometry analysis determined that L. casei WYS3 detoxified chlorpyrifos via P-O-C cleavage. Real-time polymerized chain reaction analysis determined that organophosphorus hydrolase gene expression tripled after the addition of chlorpyrifos to LAB cultures, compared with the control group (without chlorpyrifos). This paper highlights the potential use of LAB starter cultures for the detoxification and removal of chlorpyrifos residues in the environment. PMID:26852781

  19. Phytoremediation of chlorpyrifos in aqueous system by riverine macrophyte, Acorus calamus: toxicity and removal rate.

    Science.gov (United States)

    Wang, Qinghai; Li, Cui; Zheng, Ruilun; Que, Xiaoe

    2016-08-01

    The potential of Acorus calamus to remove chlorpyrifos from water was assessed under laboratory conditions. Toxic effects of the insecticide in A. calamus were evaluated using pulse-amplitude modulated chlorophyll fluorescence techniques as well. At exposure concentrations above 8 mg L(-1), A. calamus showed obvious phytotoxic symptom with significant reduction in quantum efficiency of PSII (ΦPSII) and photochemical quenching coefficient (qP) in 20-day test; the inhibition of maximal quantum efficiency of PSII (Fv/Fm) was accompanied by a significant rise in initial chlorophyll fluorescence (Fo) within 15-day exposures. Fv/Fm and Fo recover to the normal level after 20-day exposure. The reduced removal rate to chlorpyrifos was observed with increase of initial chlorpyrifos concentrations. At application levels of 1, 2, and 4 mg L(-1), the disappearance rate of chlorpyrifos in the hydroponic system with plants was significantly greater than that without plants during the 20-day test periods. Chlorpyrifos was taken up from medium and transferred to above ground tissues by the plant and significant amounts of chlorpyrifos accumulated in plant tissues. The result indicated that A. calamus can promote the disappearance of chlorpyrifos from water and may be used for phytoremediation of water contaminated with a relatively low concentration of chlorpyrifos insecticide (<4 mg L(-1)). PMID:27154841

  20. Environmental Behavior of Chlorpyrifos and Endosulfan in a Tropical Soil in Central Brazil.

    Science.gov (United States)

    Dores, Eliana F G C; Spadotto, Claudio A; Weber, Oscarlina L S; Dalla Villa, Ricardo; Vecchiato, Antonio B; Pinto, Alicio A

    2016-05-25

    The environmental behavior of chlorpyrifos and endosulfan in soil was studied in the central-western region of Brazil by means of a field experiment. Sorption was evaluated in laboratory batch experiments. Chlorpyrifos and endosulfan were applied to experimental plots on uncultivated soil and the following processes were studied: leaching, runoff, and dissipation in top soil. Field dissipation of chlorpyrifos and endosulfan was more rapid than reported in temperate climates. Despite the high Koc of the studied pesticides, the two endosulfan isomers and endosulfan sulfate as well as chlorpyrifos were detected in percolated water. In runoff water and sediment, both endosulfan isomers and endosulfan sulfate were detected throughout the period of study. Observed losses of endosulfan by leaching (below a depth of 50 cm) and runoff were 0.0013 and 1.04% of the applied amount, whereas chlorpyrifos losses were 0.003 and 0.032%, respectively. Leaching of these highly adsorbed pesticides was attributed to preferential flow. PMID:26635198

  1. Review of Toxicology of Atrazine and Chlorpyrifos on Fish

    Institute of Scientific and Technical Information of China (English)

    WANG Xu; LI Jilong; XING Houjuan; XU Shiwen

    2011-01-01

    Atrazine (ATR) and chlorpyrifos (CPF) are widely used in agriculture, but have resulted in a series of toxicological and environmental problems. They were heavily used which have potential threat to fish and rodents. Several recent laboratory studies have shown ATR and CPF could lead to oxidative damage, immunocyte reduced and inhibit acetylcholinesterase (ACHE). In order to clarify the toxicity of ATR and CPF, this paper summarized the adverse effects of ATR and CPF on reproduction, nerve and immune systems in fish.

  2. Mass spectrometry identifies covalent binding of soman, sarin, chlorpyrifos oxon, diisopropyl fluorophosphate, and FP-biotin to tyrosines on tubulin: a potential mechanism of long term toxicity by organophosphorus agents

    OpenAIRE

    Grigoryan, Hasmik; Schopfer, Lawrence M.; Thompson, Charles M.; Alvin V Terry; Masson, Patrick; Lockridge, Oksana

    2008-01-01

    Chronic low dose exposure to organophosphorus poisons (OP) results in cognitive impairment. Studies in rats have shown that OP interfere with microtubule polymerization. Since microtubules are required for transport of nutrients from the nerve cell body to the nerve synapse, it has been suggested that disruption of microtubule function could explain the learning and memory deficits associated with OP exposure. Tubulin is a major constituent of microtubules. We tested the hypothesis that OP bi...

  3. Toxicity assessing for chlorpyrifos-contaminated soil with three different earthworm test methods

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-ping; DUAN Chang-qun; FU Hui; CHEN Yu-hui; WANG Xue-hua; YU Ze-fen

    2007-01-01

    Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In the present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.

  4. Cu(2+) and Fe(2+) mediated photodegradation studies of soil-incorporated chlorpyrifos.

    Science.gov (United States)

    Rafique, Nazia; Tariq, Saadia R; Ahad, Karam; Taj, Touqeer

    2016-03-01

    The influences of Cu(2+) and Fe(2+) on the photodegradation of soil-incorporated chlorpyrifos were investigated in the present study. The soil samples spiked with chlorpyrifos and selected metal ions were irradiated with UV light for different intervals of time and analyzed by HPLC. The unsterile and sterile control soil samples amended with pesticides and selected metals were incubated in the dark at 25 °C for the same time intervals. The results of the study evidenced that photodegradation of chlorpyrifos followed the first-order kinetics. The dissipation t0.5 of chlorpyrifos was found to decrease from 41 to 20 days under UV irradiation. The rate of chlorpyrifos photodegradation was increased in the presence of both metals, i.e., Cu(2+) and Fe(2+). Thus, initially observed t0.5 of 19.8 days was decreased to 4.39 days in the case of Cu(+2) and 19.25 days for Fe(+2). Copper was found to increase the rate of photodegradation by 4.5 orders of magnitude while the microbial degradation of chlorpyrifos was increased only twofold. The microbial degradation of chlorpyrifos was only negligibly affected by Fe(2+) amendment. The studied trace metals also affected the abiotic degradation of the pesticide in the order Cu(2+) > Fe(2+). PMID:26507736

  5. Degradation of chlorpyrifos in laboratory soil and its impact on soil microbial functional diversity

    Institute of Scientific and Technical Information of China (English)

    FANG Hua; YU Yunlong; CHU Xiaoqiang; WANG Xiuguo; YANG Xiaoe; YU Jingquan

    2009-01-01

    Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory conditions. The degradation half-lives of chlorpyrifos at levels of 4, 8, and 12 mg/kg in soil were calculated to be 14.3, 16.7, and 18.0 d, respectively. The Biolog study showed that average well color development (AWCD) in soils was significantly (P < 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to the similar level as the control. A similar variation in the diversity indices (Simpson index 1/D and McIntosh index U) in chlorpyrifos-treated soils was observed, no significant difference in the Shannon-Wiener index H' was found in these soils. With increasing chlorpyrifos concentration, the half-lives of chlorpyrifos were significantly (P ≤ 0.05) extended and its inhibitory effects on soil microorganisms were aggravated. It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity.

  6. Genetics and preliminary mechanism of chlorpyrifos resistance in Phenacoccus solenopsis Tinsley (Homoptera: Pseudococcidae).

    Science.gov (United States)

    Afzal, Muhammad Babar Shahzad; Ijaz, Mamuna; Farooq, Zahra; Shad, Sarfraz Ali; Abbas, Naeem

    2015-03-01

    Cotton mealybug, Phenacoccus solenopsis Tinsley, is a serious pest of cotton and other crops and infestation by this pest results in yield losses that affect the economy of Pakistan. Various groups of insecticides have been used to control this pest but resistance development is a major factor that inhibits its control in the field. Chlorpyrifos is a common insecticide used against many pests including P. solenopsis. The present experiment was designed to assess the genetics and mechanism of chlorpyrifos resistance and to develop a better resistance management strategy and assess the genetics and mechanism of chlorpyrifos resistance. Before selection, the field strain showed 3.1-fold resistance compared to the susceptible strain (CSS). After 8 rounds of selection with chlorpyrifos, a selected population developed a 191.0-fold resistance compared to the CSS. The LC50 values of F1 (CRR ♀ × CSS ♂) and F1(†) (CRR ♂ × CSS ♀) strains were not significantly different and dominance (DLC) values were 0.42 and 0.55. Reciprocal crosses between chlorpyrifos susceptible and resistant strains indicated that resistance was autosomal and incompletely recessive. The monogenic model of fit test and calculation of number of genes segregating in the chlorpyrifos resistant strain demonstrated that resistance is controlled by multiple genes. A value of 0.59 was calculated for realized heritability for chlorpyrifos resistance. Synergism bioassays with piperonyl butoxide and S, S, S-butyl phosphorotrithioate showed that chlorpyrifos resistance was associated with microsomal oxidases and esterases. It was concluded that chlorpyrifos resistance in P. solenopsis was autosomally inherited, incompletely recessive and polygenic. These findings would be helpful to improve the management of P. solenopsis.

  7. Non-accidental chlorpyrifos poisoning-an unusual cause of profound unconsciousness.

    Science.gov (United States)

    Lee, Jiun-Chang; Lin, Kuang-Lin; Lin, Jainn-Jim; Hsia, Shao-Hsuan; Wu, Chang-Teng

    2010-04-01

    Chlorpyrifos is an organophosphorus anticholinesterase insecticide, and organophosphate intoxication can induce symptoms such as miosis, urination, diarrhea, diaphoresis, lacrimation, excitation of central nervous system, salivation, and consciousness disturbance (MUDDLES). Although accidental poisoning of children with drugs and chemicals is a common cause for consciousness disturbance in children, the possibility of deliberate poisoning is rarely considered. We report on a healthy 5-year 6-month-old boy with recurrent organophosphate intoxication. Reports of chlorpyrifos intoxication in children are quite rare. This case report demonstrates decision-making process and how to disclose deliberate chlorpyrifos poisoning of the toddler by the stepmother, another example of Munchausen syndrome by proxy. PMID:19763618

  8. Role of Ocimum sanctum as a Genoprotective Agent on Chlorpyrifos-Induced Genotoxicity

    OpenAIRE

    Khanna, Asha; Shukla, Poonam; Tabassum, Shajiya

    2011-01-01

    Protective effect of Ocimum sanctum was evaluated on chlorpyrifos-induced genotoxicity in in vivo and in vitro models. Two different concentrations of pesticide were taken, i.e., 1/5 and 1/15 of LD50 of chlorpyrifos for the in vivo study. Rats were pre-treated orally with O. sanctum extract (OE) at 50 mg/kg b.wt. For the in vitro studies, human lymphocyte cultures were exposed to 75 μg/ml chlorpyrifos with and without OE. Structural and numerical (both aneuploidy and euploidy types) chromosom...

  9. Acute Toxicity and Neurotoxicity of Chlorpyrifos in Black Tiger Shrimp, Penaeus monodon

    OpenAIRE

    Tassanee Eamkamon; Sirawut Klinbunga; Kumthorn Thirakhupt; Piamsak Menasveta; Narongsak Puanglarp

    2012-01-01

    Acute toxicity and neurotoxicity of chlorpyrifos were determined in black tiger shrimp, P. monodon. LC50 values after 24 to 96 h of exposure were between 149.55 and 59.16 nmol/L. To determine the neurotoxicity of chlorpyrifos, the inhibition of acetylcholinesterase was monitored in the gill of the shrimps exposed to lethal (0.019, 0.194, and 1.942 µmol/L) and sub-lethal (0.019, 0.194, and 1.942 nmol/L) concentrations of chlorpyrifos. In lethal dose exposure, the AChE activities observed in sh...

  10. INCREASED SUSCEPTIBILITY OF THE SPONTANEOUSLY HYPERTENSIVE RAT TO CHLORPYRIFOS, AN ORGANOPHOSPHATE PESTICIDE.

    Science.gov (United States)

    Hypertension and hypothermia are common symptoms in rats exposed to chlorpyrifos (CHP), an organophosphate (OP)-based pesticide. CHP inhibits acetylcholinesterase (AChE) activity resulting in central and peripheral stimulation of cholinergic pathways involved in blood pressure ...

  11. THE MUSCARINIC ANTAGONIST SCOPOLAMINE ATTENUATES CHLORPYRIFOS INDUCED HYPOTHERMIA IN THE DEVELOPING RAT.

    Science.gov (United States)

    Chlorpyrifos (CHP), an anticholinesterase organophosphate (OP) pesticide, induces acute hypothermia in adult and developing rats. Previously we demonstrated that thermoregulation in preweanling pups is markedly more sensitive to the neurotoxic effects of CHP than in adults. The c...

  12. THE EFFECTS OF CHRONIC EXERCISE CONDITIONING ON THERMOREGULATORY RESPONSE TO CHLORPYRIFOS IN FEMALE RATS.

    Science.gov (United States)

    Chronic exercise conditioning has been shown to alter basal thermoregulatory processes (change in thermoregulatory set-point) as well as the response to infectious fever. Chlorpyrifos (CHP), an organophosphate pesticide, causes an acute period of hypothermia followed by a delaye...

  13. Feasibility of constructed wetlands for removing chlorothalonil and chlorpyrifos from aqueous mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Sherrard, R.M.; Bearr, J.S.; Murray-Gulde, C.L.; Rodgers, J.H.; Shah, Y.T

    2004-02-01

    Chlorpyrifos (an insecticide) and chlorothalonil (a fungicide) are transported in stormwater runoff and can be lethal to receiving aquatic system biota. This study determined removal rates of chlorpyrifos and chlorothalonil in simulated stormwater runoff treated in constructed wetland mesocosms. Using sentinel species, Ceriodaphnia dubia and Pimephales promelas, observed declines in toxicity of the simulated runoff after treatment were 98 and 100%, respectively. First order removal rates were 0.039/h for chlorpyrifos and 0.295/h for chlorothalonil in these experiments. Constructed wetland mesocosms were effective for decreasing concentrations of chlorpyrifos and chlorothalonil in simulated stormwater runoff, and decreasing P. promelas and C. dubia mortality resulting from these exposures. The results from this study indicate that constructed wetlands could be part of an efficient mitigation strategy for stormwater runoff containing these pesticides. - Constructed wetlands have potential for treatment of pesticide mixtures in stormwater runoff.

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

    Science.gov (United States)

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

  15. Genotoxicity of Chlorpyrifos and the Antimutagenic Role of Lettuce Leaves in Male Mice

    Directory of Open Access Journals (Sweden)

    Kamilia Badrakhan Abdelaziz

    2010-11-01

    Full Text Available Chlorpyrifos [O O-diethyl-O-(3 5 6-trichloro-2-pyridyl-phosphorothioate] is one of the most widelyused organophosphate insecticides. Previous studies proved that chlorpyrifos, at different doses,induced genotoxicity. In Egyptian foods, the residual levels of pesticides are often higher than thosefound in developed country ones. So the aim of this research was to evaluate the genotoxicity of theinsecticide chlorpyrifos at doses equal to its maximum residue limit (MRL in the leafy vegetables, itsdouble and quadruple (0.5, 1 and 2 mg/kg body weight in somatic and germ cells of male mice.In addition to that, evaluating the role of lettuce leaves as antigenotoxic in reducing the genotoxiceffects of chlorpyrifos tested doses when concurrently administrated to these animals. The studywas conducted on adult male laboratory mice at three levels: bone marrow cells as a model formitotic chromosome aberrations, spermatocytes as a model for meiotic chromosomes and spermcount and morphology. The results of the present study indicate that the treatment of male micewith chlorpyrifos by oral gavages for three months induced significant increase in the frequencies oftotal chromosomal aberrations in both somatic and germ cells in relation to control groups. Resultsof the sperm analysis showed that chlorpyrifos induced significant decrease in the sperm countwhen compared to negative control. Furthermore, it induced significant increase in head and tailsperm abnormalities, among which coiled tail was considered the most obvious sperm abnormalityinduced by chlorpyrifos. At the same time, the present study indicated that lettuce leaves feedconcurrently with three doses of chlorpyrifos could not protect cells from damage.

  16. SEM study of ultrastructural changes in branchial architecture of Ctenopharyngodon idella (Cuvier & Valenciennes) exposed to chlorpyrifos

    OpenAIRE

    Kaur Mandeep; Jindal Rajinder

    2016-01-01

    We evaluated structural modifications in the branchial architecture of grass carp, Ctenopharyngodon idella, chronically exposed to chlorpyrifos (an organophosphate) using scanning electron microscopy (SEM). Static renewal tests were conducted for 96 h to determine the LC50 of chlorpyrifos to the fish. Physicochemical analysis of water was done using standard methods. To assess the effect of chronic toxicity, fish were exposed to two sublethal concentrations...

  17. Sub-lethal toxicity of chlorpyrifos on Common carp, Cyprinus carpio (Linnaeus, 1758): Biochemical response

    OpenAIRE

    Mahdi Banaee; Behzad Nematdoust Haghi; Ahmed Th. A. Ibrahim

    2014-01-01

    Chlorpyrifos, an organophosphate pesticide, is widely used to control pests in agriculture farms and orchards of fruit trees. In this study, the fish were exposed to sub-lethal concentrations of chlorpyrifos which were determined based on numerical value of 96 h LC50. Blood was sampled after 10, 20 and 30 days and biochemical parameters including glucose, total protein, albumin, globulin, triglyceride and cholesterol levels, and aspartate aminotransferase (AST), alanine aminotransferase (ALT)...

  18. Evaluating Oxidative Stress Factors Induced by Chlorpyrifos Poisoning in Plasma of Wistar Rat

    OpenAIRE

    Saberi, M; A Zare’i Mahmoudabadi; M Fasihi Ramandi; A. Kazemi; J Rasouli Vani

    2014-01-01

    Introduction: Chlorpyrifos (CPF) is a broad-spectrum organophosphorus insecticide that has been used abundantly over the globe during the past 40 years. Chemical pesticides may induce oxidative stress via generating free radicals and altering antioxidant levels of the free radical scavenging enzyme activity. Therefore, this study aimed to evaluate the toxicity of Chlorpyrifos-induced oxidative stress in the plasma samples of Wistar rat. Methods: Twenty-four male Wistar rats were selected r...

  19. Update of the morbidity experience of employees potentially exposed to chlorpyrifos

    OpenAIRE

    Burns, C J; Cartmill, J. B.; Powers, B. S.; Lee, M K

    1998-01-01

    OBJECTIVES: Chlorpyrifos, an organophosphate ingredient of several important insecticides, has been manufactured at The Dow Chemical Company for 25 years. A previous morbidity study among employees of The Dow Chemical Company found no increased prevalence of illness or symptoms among employees potentially exposed to chlorpyrifos from 1977 to 1985 compared with matched controls. The purpose of the current study was to update the original study to 1994, thereby increasing the statistical ...

  20. Chlorpyrifos-induced Histopathological Alterations in Duttaphrynus melanostictus (Schneider 1799) Tadpoles: Evidence from Empirical Trials

    OpenAIRE

    M. G. D. K. Bandara; M. R. Wijesinghe; W D Ratnasooriya; A. A. H. Priyani

    2012-01-01

    This paper reports the histopathological responses of the gill, liver and tail muscle tissues in tadpoles of the Asian Common Toad Duttaphrynus melanostictus (Schneider, 1799) exposed to chlorpyrifos a common organophosphorus pesticide. Tadpoles of Gosner stages 24-26 were continuously exposed to low, mid and high (500, 1000 and 1500 µgl–1) concentrations of chlorpyrifos for two weeks. Histological alterations in the tissues of the surviving larvae were microscopically examined both at the en...

  1. Residues of 14C-chlorpyrifos in coconut by radiotracer techniques

    International Nuclear Information System (INIS)

    A coconut tree was root-infused with 5 g a.i. chlorpyrifos (Lorsban plus 1.4 uCi of 14C-chlorpyrifos. Coconut samples both young and mature, were taken 24 h up to 60 days after root infusion. Analysis of the meat and water was done. The maximum uptake of chlorpyrifos equivalents was on the 13th day after root infusion both in mature and young fruit. The residue in water reached the peak on the 20th day after infusion and declined thereafter. A preharvest interval (PHI) of more than 60 days maybe recommended for safe consumption. The usual practice of storing copra in treated warehouses until it is processed into oil was simulated in the laboratory to determine the residues absorbed on the meat. Forty kg of copra with moisture content of 7-12% were stored in an improvised warehouse, i.e. 1 m x 1.5 m x 1 m wooden box, which was treated with 100 ml 1% a.i. Lorsban 50 WP plus 100 uCi 14C-chlorpyrifos for protection against insects. Analysis showed that 14C-chlorpyrifos equivalents ranged from 22.6 mg/kg on the 30th day to 8.2 mg/kg on the 90th day with a 63.7% reduction in residues. Bound residues were detected on samples stored for 60-90 days, with levels of 1.0 to 0.2 ug/g 14 C-chlorpyrifos equivalents. This is within the Maximum Residue Limit of 2 mg/kg set by FAO/WHO for chlorpyrifos in most agricultural commodities. Chlorpyrifos residues were also determined at various stages of refining and processing of crude coconut oil. It was subjected to alkali refining, bleaching and finally steaming. The residues were reduced by as much as 32.7%. (author). 18 refs.; 2 figs.; 3 tabs

  2. Persistence of chlorpyrifos, diazinon and dimethoate sprayed in the greenhouse environment during hydroponic cultivation of Gerbera

    OpenAIRE

    P. Hatzilazarou, Stefanos; Charizopoulos, Emmanouel; Papadopoulou-Mourkidou, Euphemia; S. Economou, Athanasios

    2005-01-01

    International audience The fate and behavior of chlorpyrifos, diazinon and dimethoate in a greenhouse installation during hydroponic cultivation of Gerbera was investigated. Their concentrations in the greenhouse air were related to their physicochemical properties. Thus, diazinon exhibited the highest concentration in the greenhouse air 2 hours after application, while chlorpyrifos and dimethoate were measured at lower concentrations. Afterwards, a rapid decrease was recorded. The concent...

  3. Study on Immunochemical Assays for the Organophosphorus Insecticide Chlorpyrifos

    Institute of Scientific and Technical Information of China (English)

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

    2004-01-01

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

  4. Toxicological effects of chlorpyrifos on growth, enzyme activity and chlorophyll a synthesis of freshwater microalgae.

    Science.gov (United States)

    Chen, Shangchao; Chen, Mindong; Wang, Zhuang; Qiu, Weijian; Wang, Junfeng; Shen, Yafei; Wang, Yajun; Ge, Shun

    2016-07-01

    This paper aims to acquire the experimental data on the eco-toxicological effects of agricultural pollutants on the aquatic plants and the data can support the assessment of toxicity on the phytoplankton. The pesticide of Chlorpyrifos used as a good model to investigate its eco-toxicological effect on the different microalgae in freshwater. In order to address the pollutants derived from forestry and agricultural applications, freshwater microalgae were considered as a good sample to investigate the impact of pesticides such as Chlorpyrifos on aquatic life species. Two microalgae of Chlorella pyrenoidosa and Merismopedia sp. were employed to evaluate toxicity of Chlorpyrifos in short time and long time by means of measuring the growth inhibition rate, the redox system and the content of chlorophyll a, respectively. In this study, the results showed that EC50 values ranging from 7.63 to 19.64mg/L, indicating the Chlorpyrifos had a relatively limited to the growth of algae during the period of the acute toxicity experiment. Moreover, when two kinds of algae were exposed to a medium level of Chlorpyrifos, SOD and CAT activities were importantly advanced. Therefore, the growth rate and SOD and CAT activities can be highly recommended for the eco-toxicological assessment. In addition, chlorophyll a also could be used as a targeted parameter for assessing the eco-toxicity of Chlorpyrifos on both Chlorella pyrenoidosa and Merismopedia sp. PMID:27314761

  5. Acute Toxicity and Neurotoxicity of Chlorpyrifos in Black Tiger Shrimp, Penaeus monodon

    Directory of Open Access Journals (Sweden)

    Tassanee Eamkamon

    2012-01-01

    Full Text Available Acute toxicity and neurotoxicity of chlorpyrifos were determined in black tiger shrimp, P. monodon. LC50 values after 24 to 96 h of exposure were between 149.55 and 59.16 nmol/L. To determine the neurotoxicity of chlorpyrifos, the inhibition of acetylcholinesterase was monitored in the gill of the shrimps exposed to lethal (0.019, 0.194, and 1.942 µmol/L and sub-lethal (0.019, 0.194, and 1.942 nmol/L concentrations of chlorpyrifos. In lethal dose exposure, the AChE activities observed in shrimp exposed to 0.194, and 1.942 µmol/L of chlorpyrifos were significantly lower (1.7 and 3.3 times than that of control shrimp after 30 min of exposure (p<0.05. In sub-lethal exposure tests, the AChE activity of shrimp was significantly lower (1.9 times than that of control shrimp after exposure to 1.942 nmol/L of chlorpyrifos for 72 h (p<0.05. The sensitive reduction of AChE activity at the sub-lethal concentration, which was 30 times lower than 96 h LC50 value found in this study, indicates the potential use as a biomarker of chlorpyrifos exposure.

  6. Development of a freeze-dried fungal wettable powder preparation able to biodegrade chlorpyrifos on vegetables.

    Directory of Open Access Journals (Sweden)

    Jie Liu

    Full Text Available Continuous use of the pesticide chlorpyrifos has resulted in harmful contaminations in environment and species. Based on a chlorpyrifos-degrading fungus Cladosporium cladosporioides strain Hu-01 (collection number: CCTCC M 20711, a fungal wettable powder preparation was developed aiming to efficiently remove chlorpyrifos residues from vegetables. The formula was determined to be 11.0% of carboxymethyl cellulose-Na, 9.0% of polyethylene glycol 6000, 5.0% of primary alcohol ethoxylate, 2.5% of glycine, 5.0% of fucose, 27.5% of kaolin and 40% of freeze dried fungi by response surface methodology (RSM. The results of quality inspection indicated that the fungal preparation could reach manufacturing standards. Finally, the degradation of chlorpyrifos by this fungal preparation was determined on pre-harvest cabbage. Compared to the controls without fungal preparation, the degradation of chlorpyrifos on cabbages, which was sprayed with the fungal preparation, was up to 91% after 7 d. These results suggested this freeze-dried fungal wettable powder may possess potential for biodegradation of chlorpyrifos residues on vegetables and provide a potential strategy for food and environment safety against pesticide residues.

  7. Sediment microbes and biofilms increase the bioavailability of chlorpyrifos in Chironomus riparius (Chironomidae, Diptera).

    Science.gov (United States)

    Widenfalk, Anneli; Lundqvist, Anna; Goedkoop, Willem

    2008-10-01

    In a microcosm study, the importance of different sources of organic matter (humic acids, sterile sediment, sediment, and a microbial extract) for the bioavailability of the hydrophobic pesticide chlorpyrifos to Chironomus riparius larvae was quantified. In the last two treatments biofilms were allowed to grow before (14)C-chlorpyrifos addition. Chlorpyrifos accumulation was quantified after 25 h of exposure and after 21 h of depuration. Larval accumulation was twice as high in the microbial extract treatment (447+/-79 microg/kg ww larvae) and 1.7 times higher in the sediment treatment (371+/-33 microg/kg). After depuration, chlorpyrifos accumulation in larval tissue showed even higher differences; 3.1 times higher tissue concentrations in the microbial extract treatment (218+/-21 microg/kg) and 2.2 times higher in the sediment treatment (156+/-35 microg/kg). In contrast, chlorpyrifos accumulation in the humic acid and sterile sediment did not differ from that in controls. These results show that living microbes and biofilms, by creating a microenvironment and providing food for larvae, markedly increase the bioavailability of chlorpyrifos to Chironomus riparius.

  8. Rapid and highly efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) catalysed by in situ generated I2 using Oxone®/KI or cerium ammonium nitrate (CAN)/KI systems under mild conditions

    Indian Academy of Sciences (India)

    Eskandar Kolvari; Ardeshir Khazaei; Mohammad Ali Zolfigol; Nadiya Koukabi; Maryam Gilandoust; Neda Bakhit

    2011-09-01

    Structurally diverse alcohols and phenols were trimethylsilylated in clean and efficient reactions with hexamethyldisilazane (HMDS) in the presence of a catalytic amount of I2 generated in situ from Oxone®/KI or CAN/KI systems. The reactions occur rapidly in good to high yields in wet CH2Cl2 at room temperature.

  9. Chlorpyrifos exposure in farmers and urban adults: Metabolic characteristic, exposure estimation, and potential effect of oxidative damage.

    Science.gov (United States)

    Wang, Lei; Liu, Zhen; Zhang, Junjie; Wu, Yinghong; Sun, Hongwen

    2016-08-01

    Chlorpyrifos is a widely used organophosphorus pesticide that efficiently protects crops against pests. However, recent studies suggest that severe exposure to chlorpyrifos may present adverse health effects in human. To analyze the exposure level and metabolic characteristics of chlorpyrifos pesticide in urban adults and farmers with/without occupation pesticide contact, the occurrence of urinary chlorpyrifos and methyl chlorpyrifos (CP-me), as well as their metabolite, 3,5,6-trichloro-2-pyridinol (TCPy), was determined in farmers of an agricultural village in China, and in urban adults of a nearby town. The geometric mean (GM) concentrations of TCPy, which is the major marker of chlorpyrifos exposure, were 4.29 and 7.57μg/g-creatinine in urban adults and farmers before pesticide application, respectively. Chlorpyrifos spraying significantly increased the concentrations of urinary TCPy. In the first day after spraying, a GM concentration of 43.7μg/g-creatinine was detected in the urine specimens from farmers, which decreased to 38.1 and 22.8μg/g-creatinine in the second and third day after chlorpyrifos spraying. The ratio of TCPy and its parent compounds, i.e. chlorpyrifos and CP-me, was positively associated with the sum concentration of urinary chlorpyrifos, CP-me, and TCPy, suggesting the increasing metabolic efficiency of chlorpyrifos to TCPy at higher chlorpyrifos exposure levels. To estimate the farmers' occupational exposure to chlorpyrifos pesticide, a new model based on the fitted first-order elimination kinetics of TCPy was established. Occupational chlorpyrifos exposure in a farmer was estimated to be 3.70μg/kg-bw/day (GM), which is an exposure level that is higher than the recommended guideline levels. Significant increase of urinary 8-hydroxydeoxyguanosine (8-OHdG) was observed on the first day after chlorpyrifos spraying, which indicates a potential oxidative damage in farmers. However, urinary 8-OHdG returned to its baseline level within two

  10. Purification and characterization of a novel chlorpyrifos hydrolase from Cladosporium cladosporioides Hu-01.

    Science.gov (United States)

    Gao, Yan; Chen, Shaohua; Hu, Meiying; Hu, Qiongbo; Luo, Jianjun; Li, Yanan

    2012-01-01

    Chlorpyrifos is of great environmental concern due to its widespread use in the past several decades and its potential toxic effects on human health. Thus, the degradation study of chlorpyrifos has become increasing important in recent years. A fungus capable of using chlorpyrifos as the sole carbon source was isolated from organophosphate-contaminated soil and characterized as Cladosporium cladosporioides Hu-01 (collection number: CCTCC M 20711). A novel chlorpyrifos hydrolase from cell extract was purified 35.6-fold to apparent homogeneity with 38.5% overall recovery by ammoniumsulfate precipitation, gel filtration chromatography and anion-exchange chromatography. It is a monomeric structure with a molecular mass of 38.3 kDa. The pI value was estimated to be 5.2. The optimal pH and temperature of the purified enzyme were 6.5 and 40°C, respectively. No cofactors were required for the chlorpyrifos-hydrolysis activity. The enzyme was strongly inhibited by Hg²⁺, Fe³⁺, DTT, β-mercaptoethanol and SDS, whereas slight inhibitory effects (5-10% inhibition) were observed in the presence of Mn²⁺, Zn²⁺, Cu²⁺, Mg²⁺, and EDTA. The purified enzyme hydrolyzed various organophosphorus insecticides with P-O and P-S bond. Chlorpyrifos was the preferred substrate. The Km and Vmax values of the enzyme for chlorpyrifos were 6.7974 μM and 2.6473 μmol·min⁻¹, respectively. Both NH2-terminal sequencing and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometer (MALDI-TOF-MS) identified an amino acid sequence MEPDGELSALTQGANS, which shared no similarity with any reported organophosphate-hydrolyzing enzymes. These results suggested that the purified enzyme was a novel hydrolase and might conceivably be developed to fulfill the practical requirements to enable its use in situ for detoxification of chlorpyrifos. Finally, this is the first described chlorpyrifos hydrolase from fungus.

  11. Fate and effects of the insecticide chlorpyrifos in outdoor plankton-dominated microcosms in Thailand.

    Science.gov (United States)

    Daam, Michiel A; Crum, Steven J H; Van den Brink, Paul J; Nogueira, António J A

    2008-12-01

    The fate and effects of the insecticide chlorpyrifos were studied in plankton-dominated, freshwater microcosms in Thailand. Disappearance rates of chlorpyrifos from the water column in the present study were similar to those in temperate regions. Insecticide accumulation in the sediment was relatively small, with the major part in the top layer (depth, 1.5 cm). Application of chlorpyrifos led to significant changes in freshwater biological communities. Clam shrimps (Conchostraca) and the cladoceran Moina micrura were the most susceptible species (no-observed-effect concentration [NOEC], 0.1 microg/L) and macroinvertebrates the most sensitive community (NOEC, 0.1 microg/L). These results are in agreement with those from semifield experiments with chlorpyrifos in temperate regions. The results of an in situ bioassay were used to calculate a NOEC of 0.1 microg/L and a 48-h median lethal concentration of 0.6 microg/L for M. micrura, which are similar to toxicity values reported for Daphnia magna in studies in temperate regions. Overall, these findings support the use of toxicity data from temperate regions for the risk assessment of low-persistent insecticides like chlorpyrifos for aquatic communities in tropical regions. PMID:18699699

  12. Genotoxic Effects of Chlorpyrifos in Freshwater Fish Cirrhinus mrigala Using Micronucleus Assay

    Directory of Open Access Journals (Sweden)

    Anita Bhatnagar

    2016-01-01

    Full Text Available The genotoxicity of pesticides is an issue of worldwide concern and chlorpyrifos is one of the largest selling organophosphate agrochemicals that has been widely detected in surface waters of India. The studies on long term genotoxic biomarkers are limited; therefore, present study was carried out to analyze the incidence of nuclear anomalies in the blood cells of fresh water fish Cirrhinus mrigala using micronucleus (MN assay as a potential tool for assessment of genotoxicity. Acute toxicity of chlorpyrifos was evaluated by exposing fingerlings to different doses of chlorpyrifos (1/20, 1/10, and 1/5 of LC50 and LC50 was calculated as 0.44 mg L−1 using probit analysis. Blood samples were taken on days 2, 4, 8, 12, 21, 28, and 35. In general, significant effects for both concentration and duration of exposure were observed in treated fish. It was found that MN induction was highest on day 14 at 0.08 mg L−1 concentration of chlorpyrifos. It was concluded that chlorpyrifos is genotoxic pesticide causing nuclear anomalies in Cirrhinus mrigala.

  13. Sub-lethal toxicity of chlorpyrifos on Common carp, Cyprinus carpio (Linnaeus, 1758: Biochemical response

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-01-01

    Full Text Available Chlorpyrifos, an organophosphate pesticide, is widely used to control pests in agriculture farms and orchards of fruit trees. In this study, the fish were exposed to sub-lethal concentrations of chlorpyrifos which were determined based on numerical value of 96 h LC50. Blood was sampled after 10, 20 and 30 days and biochemical parameters including glucose, total protein, albumin, globulin, triglyceride and cholesterol levels, and aspartate aminotransferase (AST, alanine aminotransferase (ALT, lactate dehydrogenase (LDH, creatine kinase (CK, alkaline phosphatase (ALP and acetylcholinsetrase (AChE activities were measured. Behavioral changes in the fish were also recorded during the experiment. Unbalanced swimming, swimming in the surface water and hyperglycemia, increased blood triglyceride, and increased levels of AST, LDH and CK activities as well as decreased levels of AChE activity were important changes that were observed in the specimens exposed to chlorpyrifos during experimental periods. The most important alterations in the blood biochemical parameters were measured in the specimens exposed to 40 µg/L chlorpyrifos on the 20th and 30th day of the trial. In conclusion, results of the present study indicated that exposure to sub-lethal concentrations of chlorpyrifos as low as 40 µg/L may cause biochemical and behavioral changes in Cyprinus carpio.

  14. Degradation of chlorpyrifos alone and in combination with chlorothalonil and their effects on soil microbial populations

    Institute of Scientific and Technical Information of China (English)

    CHU Xiaoqiang; FANG Hua; PAN Xuedong; WANG Xiao; SHAN Min; FENG Bo; YU Yunlong

    2008-01-01

    In practice, pesticides are usually applied simultaneously or one after another for crop protection, and this type of pesticide application often leads to a combined contamination of pesticide residues in the soil environment. A laboratory study was conducted to investigate the influence of chlorothalonil on chlorpyrifos degradation and its effects on soil bacterial, fungal, and actinomycete populations. Under the experimental conditions here, the half-lives of chlorpyrifos alone, and in combination with chlorothalonil, at the recommended and double dosages, were measured to be 3.24, 2.77, and 2.63 d, respectively. Chlorpyrifos degradation was not significantly altered by its combination with chlorothalonil. However, the inhibitory effect of chlorpyrifos on soil microorganisms was increased by its combination with chlorothalonil, and the increase was related to the levels of chlorothalonil added. Compared to those in the controls, the populations of bacteria, fungi, and actinomycetes were significantly reduced by 44.1%, 61.1%, and 72.8%, respectively, on the first day after treatment (DAT) by chlorpyrifos alone. With the addition of chlorothalonil, the inhibition was increased to 55.2%, 79.3%, and 85.8% at the recommended dosage, and 86.0%, 94.1%, and 90.8% at the double dosage, at one DAT, respectively. The results suggested that combined effects should be taken into account to assess the actual impacts of pesticide applications.

  15. Properties and uses of chlorpyrifos in the United States.

    Science.gov (United States)

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

    2014-01-01

    Physical properties and use data provide the basis for estimating environmental exposures to chlorpyrifos (CPY) and for assessing its risks. The vapor pressure ofCPY is low, solubility in water is agricultural uses. In agricultural soils under field conditions,half-lives are shorter (2 to 120 d, N=58). The mean water-soil adsorption coefficient(Koc) of CPY is 8,216 mL g-1; negligible amounts enter plants via the roots,and it is not translocated in plants. Half-lives for hydrolysis in water are inversely dependent on pH, and range from 16 to 73 d. CPY is an inhibitor of acetylcholinesterase and is potentially toxic to most animals. Differences in susceptibility result from differences in rates of adsorption,distribution, metabolism, and excretion among species. CPY is an important tool in management of a large number of pests (mainly insects and mites) and is used on a wide range of crops in the U.S. Estimates of annual use in the U.S. from 2008 to 2012 range from 3.2 to 4.1 M kg y-1, which is about 50% less than the amount used prior to 2000. Applications to corn and soybeans accounts for 46-50%of CYP's annual use in the U.S.

  16. Warming increases chlorpyrifos effects on predator but not anti-predator behaviours.

    Science.gov (United States)

    Dinh Van, Khuong; Janssens, Lizanne; Debecker, Sara; Stoks, Robby

    2014-07-01

    Recent insights indicate that negative effects of pesticides on aquatic biota occur at concentrations that current legislation considers environmentally protective. We here address two, potentially interacting, mechanisms that may contribute to the underestimation of the impact of sublethal pesticide effects in single species tests at room temperature: the impairment of predator and antipredator behaviours and the stronger impact of organophosphate pesticides at higher temperatures. To address these issues we assessed the effects of chlorpyrifos on the predator and antipredator behaviours of larvae of the damselfly Ischnura elegans, important intermediate predators in aquatic food webs, in a common-garden warming experiment with replicated low- and high-latitude populations along the latitudinal gradient of this species in Europe. Chlorpyrifos reduced the levels of predator behavioural endpoints, and this reduction was stronger at the higher temperature for head orientations and feeding strikes. Chlorpyrifos also impaired two key antipredator behavioural endpoints, activity reductions in response to predator cues were smaller in the presence of chlorpyrifos, and chlorpyrifos caused a lower escape swimming speed; these effects were independent of temperature. This suggests chlorpyrifos may impact food web interactions by changing predator-prey interactions both with higher (predators) and lower trophic levels (food). Given that only the interaction with the lower trophic level was more impaired at higher temperatures, the overall pesticide-induced changes in food web dynamics may be strongly temperature-dependent. These findings were consistent in damselflies from low- and high-latitude populations, illustrating that thermal adaptation will not mitigate the increased toxicity of pesticides at higher temperatures. Our study not only underscores the relevance of including temperature and prey-predator interactions in ecological risk assessment but also their potential

  17. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    International Nuclear Information System (INIS)

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  18. Warming increases chlorpyrifos effects on predator but not anti-predator behaviours.

    Science.gov (United States)

    Dinh Van, Khuong; Janssens, Lizanne; Debecker, Sara; Stoks, Robby

    2014-07-01

    Recent insights indicate that negative effects of pesticides on aquatic biota occur at concentrations that current legislation considers environmentally protective. We here address two, potentially interacting, mechanisms that may contribute to the underestimation of the impact of sublethal pesticide effects in single species tests at room temperature: the impairment of predator and antipredator behaviours and the stronger impact of organophosphate pesticides at higher temperatures. To address these issues we assessed the effects of chlorpyrifos on the predator and antipredator behaviours of larvae of the damselfly Ischnura elegans, important intermediate predators in aquatic food webs, in a common-garden warming experiment with replicated low- and high-latitude populations along the latitudinal gradient of this species in Europe. Chlorpyrifos reduced the levels of predator behavioural endpoints, and this reduction was stronger at the higher temperature for head orientations and feeding strikes. Chlorpyrifos also impaired two key antipredator behavioural endpoints, activity reductions in response to predator cues were smaller in the presence of chlorpyrifos, and chlorpyrifos caused a lower escape swimming speed; these effects were independent of temperature. This suggests chlorpyrifos may impact food web interactions by changing predator-prey interactions both with higher (predators) and lower trophic levels (food). Given that only the interaction with the lower trophic level was more impaired at higher temperatures, the overall pesticide-induced changes in food web dynamics may be strongly temperature-dependent. These findings were consistent in damselflies from low- and high-latitude populations, illustrating that thermal adaptation will not mitigate the increased toxicity of pesticides at higher temperatures. Our study not only underscores the relevance of including temperature and prey-predator interactions in ecological risk assessment but also their potential

  19. Prenatal dexamethasone augments the neurobehavioral teratology of chlorpyrifos: significance for maternal stress and preterm labor.

    Science.gov (United States)

    Levin, Edward D; Cauley, Marty; Johnson, Joshua E; Cooper, Ellen M; Stapleton, Heather M; Ferguson, P Lee; Seidler, Frederic J; Slotkin, Theodore A

    2014-01-01

    Glucocorticoids are the consensus treatment given in preterm labor and are also elevated by maternal stress; organophosphate exposures are virtually ubiquitous, so human developmental coexposures to these two agents are common. This study explores how prenatal dexamethasone exposure modifies the neurobehavioral teratology of chlorpyrifos, one of the most widely used organophosphates. We administered dexamethasone to pregnant rats on gestational days 17-19 at a standard therapeutic dose (0.2 mg/kg); offspring were then given chlorpyrifos on postnatal days 1-4, at a dose (1 mg/kg) that produces barely-detectable (<10%) inhibition of brain cholinesterase activity. Dexamethasone did not alter brain chlorpyrifos concentrations, nor did either agent alone or in combination affect brain thyroxine levels. Assessments were carried out from adolescence through adulthood encompassing T-maze alternation, Figure 8 maze (locomotor activity, habituation), novelty-suppressed feeding and novel object recognition tests. For behaviors where chlorpyrifos or dexamethasone individually had small effects, the dual exposure produced larger, significant effects that reflected additivity (locomotor activity, novelty-suppressed feeding, novel object recognition). Where the individual effects were in opposite directions or were restricted to only one agent, we found enhancement of chlorpyrifos' effects by prenatal dexamethasone (habituation). Finally, for behaviors where controls displayed a normal sex difference in performance, the combined treatment either eliminated or reversed the difference (locomotor activity, novel object recognition). Combined exposure to dexamethasone and chlorpyrifos results in a worsened neurobehavioral outcome, providing a proof-of-principle that prenatal glucocorticoids can create a subpopulation with enhanced vulnerability to environmental toxicants.

  20. [Effects of single and co-exposure of Cu and chlorpyrifos on the toxicity of earthworm].

    Science.gov (United States)

    Xu, Dong-mei; Wang, Yan-hua; Wang, Nan; Rao, Gui-wei

    2015-01-01

    Combined pollution of heavy metal and pesticide had posed a serious threat to soil ecology and human living environment. As two common types of pollutants in soil environment, the environmental effects of combined pollution of Cu and chlorpyrifos are worth for attention. The acute lethal effects and avoiding behavior of single and co-exposure of Cu and chlorpyrifos on earthworms were analyzed by using the methods of standard OECD filter paper test and artificial soil test. Results showed that the LC(50,48 h) and LC(50,14 d) of the acute toxicity of Cu on earthworm in filter paper test and in artificial soil test were 2.23 microg x cm(-2) and 496.05 mg x kg(-1), respectively. The LC(50,48 h) and LC(50,14 d) of the acute toxicity of chlorpyrifos on earthworm in filter paper test and in artificial soil test were 5.94 microg x cm(-2) and 186.07 mg x kg(-1), respectively. In filter paper test and artificial soil test, the joint acute toxicity of Cu and chlorpyrifos showed an additive effect while the concentration was 1:1. The type of combined effects of co-exposure of Cu and chlorpyrifos was synergistic effect and antagonistic effect in filter paper test and artificial soil test, respectively, while the toxicity was 1:1. The results of avoidance behavior test showed that the joint effect of Cu and chlorpyrifos on the avoidance behavior of earthworms was antagonistic. PMID:25898676

  1. Reactive oxygen species regulated mitochondria-mediated apoptosis in PC12 cells exposed to chlorpyrifos

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Park, Jae Hyeon [Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2012-09-01

    Reactive oxidative species (ROS) generated by environmental toxicants including pesticides could be one of the factors underlying the neuronal cell damage in neurodegenerative diseases. In this study we found that chlorpyrifos (CPF) induced apoptosis in dopaminergic neuronal components of PC12 cells as demonstrated by the activation of caspases and nuclear condensation. Furthermore, CPF also reduced the tyrosine hydroxylase-positive immunoreactivity in substantia nigra of the rat. In addition, CPF induced inhibition of mitochondrial complex I activity. Importantly, N-acetyl cysteine (NAC) treatment effectively blocked apoptosis via the caspase-9 and caspase-3 pathways while NAC attenuated the inhibition of mitochondrial complex I activity as well as the oxidative metabolism of dopamine (DA). These results demonstrated that CPF-induced apoptosis was involved in mitochondrial dysfunction through the production of ROS. In the response of cellular antioxidant systems to CPF, we found that CPF treatment increased HO-1 expression while the expression of CuZnSOD and MnSOD was reduced. In addition, we found that CPF treatment activated MAPK pathways, including ERK 1/2, the JNK, and the p38 MAP kinase in a time-dependent manner. NAC treatment abolished MAPK phosphorylation caused by CPF, indicating that ROS are upstream signals of MAPK. Interestingly, MAPK inhibitors abolished cytotoxicity and reduced ROS generation by CPF treatment. Our results demonstrate that CPF induced neuronal cell death in part through MAPK activation via ROS generation, suggesting its potential to generate oxidative stress via mitochondrial damage and its involvement in oxidative stress-related neurodegenerative disease. -- Highlights: ► Chlorpyrifos induces apoptosis. ► Chlorpyrifos inhibits mitochondrial complex I activity. ► ROS is involved in chlorpyrifos-induced apoptosis. ► Chlorpyrifos affects cellular antioxidant systems. ► Chlorpyrifos-induced apoptosis mediates activation of MAPK.

  2. Oxidative mechanisms contributing to the developmental neurotoxicity of nicotine and chlorpyrifos

    International Nuclear Information System (INIS)

    Nicotine and chlorpyrifos are developmental neurotoxicants that, despite their differences in structure and mechanism of action, share many aspects for damage to the developing brain. Both are thought to generate oxidative radicals; in the current study, we evaluated their ability to produce lipid peroxidation in two in vitro models of neural cell development (PC12 and SH-SY5Y cells) and for nicotine, with treatment of adolescent rats in vivo. Nicotine and chlorpyrifos, in concentrations relevant to human exposures, elicited an increase in thiobarbituric-acid-reactive species (TBARS) in undifferentiated cells, an effect that was prevented by addition of the antioxidant, Vitamin E. Initiating differentiation with nerve growth factor, which enhances nicotinic acetylcholine receptor expression, increased the TBARS response to nicotine but not chlorpyrifos, suggesting that the two agents act by different originating mechanisms to converge on the endpoint of oxidative damage. Furthermore, nicotine protected the cells from oxidative damage evoked by chlorpyrifos and similarly blocked the antimitotic effect of chlorpyrifos. Treatment of adolescent rats with nicotine elicited increases in TBARS in multiple brain regions when given in doses that simulate plasma nicotine concentrations found in smokers or at one-tenth the dose. Our results indicate that nicotine and chlorpyrifos elicit oxidative damage to developing neural cells both in vitro and in vivo, a mechanism that explains some of the neurodevelopmental endpoints that are common to the two agents. The balance between neuroprotectant and neurotoxicant actions of nicotine may be particularly important in situations where exposure to tobacco smoke is combined with other prooxidant insults

  3. Chlorpyrifos reduces nickel-induced growth retardation of the soil dwelling Collembolan Folsomia candida.

    Science.gov (United States)

    Broerse, Mieke; van Gestel, Cornelis A M

    2010-07-01

    For 7 weeks, we studied the effects on body size and growth rate of Folsomia candida exposed to nickel and chlorpyrifos and their mixtures in a natural Lufa 2.2 soil. Nickel significantly reduced the development of body size of the springtails, although no complete dose-response curve was obtained. Chlorpyrifos did not influence the springtail growth when applied alone, but significantly reduced the growth retardation induced by nickel. We showed that by monitoring the development of toxicity in time for both the single compounds and the mixtures it was possible to determine mixture interactions even when no complete dose-response curves were available for all mixture components. PMID:20185177

  4. Behavioral Responses of the Freshwater Fish, Cyprinus carpio (Linnaeus) Following Sublethal Exposure to Chlorpyrifos

    OpenAIRE

    Halappa, Ramesh; David, Muniswamy

    2009-01-01

    Common carp fingerlings were exposed to different concentrations (0.120 to 0.200 mg/L) of an organophosphate pesticide, chlorpyrifos (20% EC) for 96 h. The acute toxicity (LC50) of chlorpyrifos by static renewal (semi-static) bioassay test was found to be 0.160 mg/L. One-seventh (0.0224 mg/L) and one-fourteenth (0.0112 mg/L) of the 96 h LC50 were selected as sublethal concentrations for subacute studies. The fish were exposed to both the sublethal concentrations for 1, 7 and 14 days and allow...

  5. 两株蜡状芽孢杆菌对毒死蜱的降解动力学研究%Kinetics of chlorpyrifos degradation by Bacillus cereus strains

    Institute of Scientific and Technical Information of China (English)

    段海明

    2013-01-01

    Organophosphorus pesticides have been widely used to control insect pests in agriculture. These compounds have been implicated in several nerve and muscular diseases in humans. Large-scale manufacturing and handling of organophosphate insecticides have caused the contamination of soils, air, surface water and groundwater across the globe. Chlorpyrifos degradation has become an increasingly important area of research in recent years. The current focus has been on the development of cost effective and eco-friendly technologies for treating polluted environments. Biodegradation has offered an efficient and cheap option for such decontamination process. Similarly, biodegradation has also been the main mechanism for removed chlorpyrifos residue, especially in the treatment of discharged wastewater from the varied processes of chlorpyrifos production. The study of the degradation kinetics was useful for understanding biodegradation processes as well as estimating pollutant concentrations. The degradation of high concentration pollutants was critical for developing practical applications of degrading bacteria. In this study, two pure Bacillus cereus strains (HY-1 and HY-2) were used in chlorpyrifos biodegradation in a batch of shake-flasks. The rate and extent of biodegradation were quantified at different chlorpyrifos initial concentrations (in the range of 40~200 mg·L-1) by B. cereus through adding chorpyrifos to mineralized medium and analyzing chlorpyrifos residue at a definite time. At the same time, the effects of incubation times and size of inoculum on chlorpyrifos degradation rate were determined. The degradation rate of high chlorpyrifos concentration by B. cereus was also measured. The results showed that the appropriate incubation time of inoculum of HY-1 and HY-2 strains were 10 h and 19 h respectively. The data suggested that inoculum incubation time significantly influenced chlorpyrifos degradation efficiency. Optimum inoculum amount for the two strains

  6. Impact of single and repeated applications of the insecticide chlorpyrifos on tropical freshwater plankton communities

    NARCIS (Netherlands)

    Daam, M.A.; Brink, van den P.J.; Nogueira, A.J.A.

    2008-01-01

    This paper describes the effects of a single and a repeated application of the organophosphorus insecticide chlorpyrifos on zooplankton and phytoplankton communities in outdoor microcosms in Thailand. Treatment levels of 1 mu g L-1 were applied once or twice with a 2-week interval. Both treatments l

  7. CHANGES IN THE RAT EEG SPECTRA AND CORE TEMPERATURE AFTER EXPOSURE TO DIFFERENT DOSES OF CHLORPYRIFOS.

    Science.gov (United States)

    Our previous study showed that single exposure to 25 mg/kg (p.o.) of organophsphate pesticide chlorpyrifos (CHP) led to significant alterations in all EEG frequency bands within 0.1-50 Hz range, reduction in core temperature (Tc) and motor activity (MA). The alterations in EEG pe...

  8. Effects of chronic low concentrations of pesticides chlorpyrifos and atrazine in indoor freshwater microcosms.

    NARCIS (Netherlands)

    Brink, van den P.J.; Donk, van E.; Gylstra, R.; Crum, S.J.H.; Brock, T.C.M.

    1995-01-01

    Standards for pesticide concentrations in water are based on the laboratory toxicity of the most susceptible standard test organisms (algae, crustaceans or fish). Field studies have shown that the standards for the insecticide chlorpyrifos and the herbicide atrazine will protect aquatic ecosystems a

  9. 76 FR 25281 - Atrazine, Chloroneb, Chlorpyrifos, Clofencet, Endosulfan, et al.; Proposed Tolerance Actions

    Science.gov (United States)

    2011-05-04

    ... AGENCY 40 CFR Part 180 Atrazine, Chloroneb, Chlorpyrifos, Clofencet, Endosulfan, et al.; Proposed..., modify certain tolerances for atrazine, establish tolerances for endosulfan, and make minor revisions to..., EPA is proposing to modify certain tolerances for the herbicide atrazine. In addition, EPA...

  10. The effects of chlorpyrifos on cholinesterase activity and foraging behavior in the dragonfly, Anax junius (Odonata)

    Science.gov (United States)

    Brewer, S.K.; Atchison, G.J.

    1999-01-01

    We examined head capsule cholinesterase (ChE) and foraging behavior in nymphs of the dragonfly, Anax junius, exposed for 24 h to 0.2, 0.6 and 1.0 ??g l-1 of the organophosphorus (OP) insecticide, chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) phosphorothioate]. The invertebrate community is an important component of the structure and function of wetland ecosystems, yet the potential effects of insecticides on wetland ecosystems are largely unknown. Our objectives were to determine if exposure to environmentally realistic concentrations of chlorpyrifos affected foraging behavior and ChE activity in head capsules of dragonfly nymphs. Nymphs were exposed to different concentrations of chlorpyrifos and different prey densities in a factorial design. ChE activities and foraging behaviors of treated nymphs were not statistically different (p ??? 0.05) from control groups. Prey density effects exerted a greater effect on dragonfly foraging than toxicant exposures. Nymphs offered higher prey densities exhibited more foraging behaviors but also missed their prey more often. High variability in ChE activities within the control group and across treated groups precluded determination of relationships between ChE and foraging behaviors. It appears that A. junius is relatively tolerant of chlorpyrifos, although the concentrations we tested have been shown in other work to adversely affect the prey base; therefore the introduction of this insecticide may have indirect adverse affects on top invertebrate predators such as Odonata.

  11. THERMOREGULATION IN THE RAT DURING CHRONIC, DIETARY EXPOSURE TO CHLORPYRIFOS, AN ORGANOPHOSPHATE INSECTICIDE.

    Science.gov (United States)

    Administration of chlorpyrifos (CHP) at a dose of 25 to 80 mg/kg (p.o.) To rats results in hypothermia followed by a fever lasting for several days. To understand if chronic, low level exposure to CHP affects thermoregulation in a comparable manner to acute administration, male L...

  12. Inhibition of acetylcholinesterase in guppies (Poecilia reticulata) by chlorpyrifos at sublethal concentrations: Methodological aspects

    Energy Technology Data Exchange (ETDEWEB)

    van der Wel, H.; Welling, W.

    1989-04-01

    Acetylcholinesterase activity is a potential biochemical indicator of toxic stress in fish and a sensitive parameter for testing water for the presence of organophosphates. A number of methodological aspects regarding the determination of the in vivo effect of chlorpyrifos on acetylcholinesterase in guppies have been investigated. It was found that with acetylthiocholine as a substrate, the contribution of pseudocholinesterase to the total cholinesterase activity can be neglected. Protection of acetylcholinesterase of guppies exposed to chlorpyrifos from additional, artifactual in vitro enzyme inhibition during homogenization is necessary. Very low concentrations of acetone in the exposure medium, resulting from dilution of the stock solution of chlorpyrifos in acetone, can result in large decreases in the oxygen content of this medium. This may affect the uptake rate of the toxic compound and, thereby, cholinesterase inhibition. Very low, sublethal concentrations of chlorpyrifos result in high inhibition levels of acetylcholinesterase (80-90%) in guppies within 2 weeks of continuous exposure. Recovery of the enzyme activity occurs after the exposed animals are kept in clean medium for 4 days, but the rate of recovery is considerably lower than the rate of inhibition.

  13. Effects of chlorpyrifos in freshwater model ecosystems: the influence of experimental conditions on ecotoxicological thresholds

    NARCIS (Netherlands)

    Wijngaarden, van R.P.A.; Brock, T.C.M.; Douglas, M.T.

    2005-01-01

    Three experiments were conducted to determine the impact of the insecticide chlorpyrifos (single applications of 0.01 to 10 µg AI litre-1) in plankton-dominated nutrient-rich microcosms. The microcosms (water volume approximately 14 litres) were established in the laboratory under temperature, light

  14. SEM study of ultrastructural changes in branchial architecture of Ctenopharyngodon idella (Cuvier & Valenciennes exposed to chlorpyrifos

    Directory of Open Access Journals (Sweden)

    Kaur Mandeep

    2016-01-01

    Full Text Available We evaluated structural modifications in the branchial architecture of grass carp, Ctenopharyngodon idella, chronically exposed to chlorpyrifos (an organophosphate using scanning electron microscopy (SEM. Static renewal tests were conducted for 96 h to determine the LC50 of chlorpyrifos to the fish. Physicochemical analysis of water was done using standard methods. To assess the effect of chronic toxicity, fish were exposed to two sublethal concentrations (1.44 μg/L and 2.41 μg/L of chlorpyrifos for 15, 30 and 60 days, after which gills were examined by SEM, which revealed changes in gill ultrastructure. Branchial alterations included distorted secondary lamellae in the form of curling and shortening, erosion in a few primary filaments and a wrinkled and denuded epithelial surface. Excessive mucosal openings (mucoid hyperplasia on the surface were observed in the gills of fish exposed to both concentrations of chlorpyrifos. Alteration in the microridge pattern of pavement cells and cracks on the gill rakers were also observed, and the intensity of the damage was found to be directly related to the toxicant concentration and exposure period. The present study revealed that the assessment of surface morphology can serve as a novel bioindicator of pollution, disease and toxicity.

  15. Effects of chlorpyrifos, carbendazim and linuron on the ecology of a small indoor aquatic microcosm

    NARCIS (Netherlands)

    Daam, M.A.; Brink, van den P.J.

    2007-01-01

    To validate the use of small indoor microcosms for the risk assessment of pesticides, the fate and effects of chlorpyrifos, carbendazim, and linuron were studied in 8.5¿liter indoor freshwater microcosms. Functional and structural responses to selected concentrations were evaluated and compared with

  16. Specific surface area effect on adsorption of chlorpyrifos and TCP by soils and modeling

    Science.gov (United States)

    The adsorption of chlorpyrifos and TCP (3,5,6, trichloro-2-pyridinol) was determined in four soils (Mollisol, Inceptisol, Entisol, Alfisol) having different specific surface areas (19–84 m2/g) but rather similar organic matter content (2.4–3.5%). Adsorption isotherms were derived from batch equilibr...

  17. Dissipation of chlorpyrifos in pakchoi-vegetated soil in a greenhouse

    Institute of Scientific and Technical Information of China (English)

    FANG Hua; YU Yun-long; WANG Xiao; SHAN Min; WU Xiao-mao; YU Jing-quan

    2006-01-01

    The dissipation of chlorpyrifos in pakchoi-vegetated soil was investigated in the summer and autumn in a greenhouse and field, respectively. The dissipation of chlorpyrifos in pakchoi-grown soil was comparatively described by fitting the residue data to seven models (1st-order, 1.5th-order, 2nd-order, RF 1st-order, RF 1.5th-order, RF 2nd-order, and bi-exponential or two-compartment models). Statistical analysis was performed using the SPSS 11.5 statistical package. The bi-exponential model was selected as the optimal model according to the coefficient of determination r2. The dissipation half-lives (DT50) of chlorpyrifos in pakchoi-vegetated soil at the recommended dose in the summer and autumn, calculated by the bi-exponential model, were 0.6 and 1.2 d in a greenhouse,0.4 and 1.0 d in a field, respectively; the corresponding values at double dose were 1.2 and 2.1 d in a greenhouse, 0.5 and 1.3 d in a field, respectively. The kinetic data indicate the dissipation of chlorpyrifos in pakchoi-grown soil in a greenhouse is slower than that in a field, and dissipates slower in the autumn than in the summer.

  18. Adsorption of chlorpyrifos, penconazole and metalaxyl from aqueous solution by modified clays.

    Science.gov (United States)

    Suciu, Nicoleta A; Capri, Ettore

    2009-08-01

    Sorption of three pesticides (chlorpyrifos, metalaxyl and penconazole) has been measured on a commercial clay montmorillonite and on the same mineral modified with either of two cationic-surfactant micelles. Both micelle-clay complexes, commercial names Cloisite 20A and Cloisite 30B, showed a good capacity to sorb all three pesticides from water, whereas their sorption on the natural montmorillonite was not described by an isotherm. Modelling sorption on both micelle-clay complexes showed that the Freundlich sorption constant (K(F)) was higher for chlorpyrifos on Cloisite 20A (K(F) = 7.76) than on Cloisite 30B (K(F) = 5.91), whereas the sorption of metalaxyl was stronger on Cloisite 30B (K(F) = 1.07) than on Cloisite 20A (K(F) = 0.57). Moreover the micelle-clay complex Cloisite 20A also showed a good affinity for penconazole, the maximum quantity adsorbed (q(m)) of 6.33 mg g(-1) being 45% more than that on Cloisite 30B. Single-batch adsorption of each pesticide onto both micelle-clay complexes was studied using the Freundlich isotherm for chlorpyrifos and metalaxyl and the Langmuir isotherm for penconazole. The Cloisite 20A micelle-clay complex was predicted to require 23% less adsorbent to treat certain volumes of wastewater containing 30 mg L(-1) chlorpyrifos, 43% more to treat metalaxyl similarly and 57% less to treat penconazole compared with Cloisite 30B. PMID:20183058

  19. Comparative and combined acute toxicity of butachlor, imidacloprid and chlorpyrifos on earthworm, Eisenia fetida.

    Science.gov (United States)

    Chen, Chen; Wang, Yanhua; Zhao, Xueping; Wang, Qiang; Qian, Yongzhong

    2014-04-01

    Various pesticides have become widespread contaminants of soils due to their large applications in agriculture and homes. An earthworm assay was used to assess the acute toxicity of butachlor, imidacloprid and chlorpyrifos with different modes of action. Ecotoxicities of these pesticides were compared for earthworm Eisenia fetida separately and in combination in artificial soil and contact filter paper tests. Imidacloprid was the most toxic for E. fetida with LC₅₀ (lethal concentration 50) values three orders magnitude lower than that of butachlor and chlorpyrifos in both tests. The toxicity of the mixtures was compared to that predicted by the concentration addition (CA) model. According to the CA model, the observed toxicities of all binary mixtures were less than additive. However, for all the mixtures in 14 d artificial soil test, and mixtures of butachlor plus chlorpyrifos and imidacloprid plus chlorpyrifos in 48 h contact filter paper test, the difference in toxicity was less than 30%, hence it was concluded that the mixtures conformed to CA. The combined effects of the pesticides in contact filter paper tests were not consistent with the results in artificial soil toxicity tests, which may be associated with the interaction of soil salts with the pesticides. The CA model provides estimates of mixture toxicity that did not markedly underestimate the measured toxicity, and therefore the CA model is the most suitable to use in ecological risk assessments of the pesticides.

  20. Prenatal nicotine changes the response to postnatal chlorpyrifos: Interactions targeting serotonergic synaptic function and cognition.

    Science.gov (United States)

    Slotkin, Theodore A; Skavicus, Samantha; Levin, Edward D; Seidler, Frederic J

    2015-02-01

    Nicotine and chlorpyrifos are developmental neurotoxicants that target serotonin systems. We examined whether prenatal nicotine exposure alters the subsequent response to chlorpyrifos given postnatally. Pregnant rats received nicotine throughout gestation at 3mg/kg/day, a regimen designed to achieve plasma levels seen in smokers; chlorpyrifos was given to pups on postnatal days (PN) 1-4 at 1mg/kg, just above the detection threshold for brain cholinesterase inhibition. We assessed long-term effects from adolescence (PN30) through full adulthood (PN150), measuring the expression of serotonin receptors and serotonin turnover (index of presynaptic impulse activity) in cerebrocortical brain regions encompassing the projections that are known targets for nicotine and chlorpyrifos. Nicotine or chlorpyrifos individually increased the expression of serotonin receptors, with greater effects on males than on females and with distinct temporal and regional patterns indicative of adaptive synaptic changes rather than simply an extension of initial injury. This interpretation was confirmed by our finding an increase in serotonin turnover, connoting presynaptic serotonergic hyperactivity. Animals receiving the combined treatment showed a reduction in these adaptive effects on receptor binding and turnover relative to the individual agents, or even an effect in the opposite direction; further, normal sex differences in serotonin receptor concentrations were dissipated or reversed, an effect that was confirmed by behavioral evaluations in the Novel Objection Recognition Test. In addition to the known liabilities associated with maternal smoking during pregnancy, our results point to additional costs in the form of heightened vulnerability to neurotoxic chemicals encountered later in life. PMID:25592617

  1. High chlorpyrifos resistance in Culex pipiens mosquitoes: strong synergy between resistance genes.

    Science.gov (United States)

    Alout, H; Labbé, P; Berthomieu, A; Makoundou, P; Fort, P; Pasteur, N; Weill, M

    2016-02-01

    We investigated the genetic determinism of high chlorpyrifos resistance (HCR), a phenotype first described in 1999 in Culex pipiens mosquitoes surviving chlorpyrifos doses ⩾1 mg l(-1) and more recently found in field samples from Tunisia, Israel or Indian Ocean islands. Through chlorpyrifos selection, we selected several HCR strains that displayed over 10 000-fold resistance. All strains were homozygous for resistant alleles at two main loci: the ace-1 gene, with the resistant ace-1(R) allele expressing the insensitive G119S acetylcholinesterase, and a resistant allele of an unknown gene (named T) linked to the sex and ace-2 genes. We constructed a strain carrying only the T-resistant allele and studied its resistance characteristics. By crossing this strain with strains harboring different alleles at the ace-1 locus, we showed that the resistant ace-1(R) and the T alleles act in strong synergy, as they elicited a resistance 100 times higher than expected from a simple multiplicative effect. This effect was specific to chlorpyrifos and parathion and was not affected by synergists. We also examined how HCR was expressed in strains carrying other ace-1-resistant alleles, such as ace-1(V) or the duplicated ace-1(D) allele, currently spreading worldwide. We identified two major parameters that influenced the level of resistance: the number and the nature of the ace-1-resistant alleles and the number of T alleles. Our data fit a model that predicts that the T allele acts by decreasing chlorpyrifos concentration in the compartment targeted in insects. PMID:26463842

  2. Morpho-toxicology of chlorpyrifos to prolactin cells of a freshwater catfish, Heteropneustes fossilis =Morpho-toxicology of chlorpyrifos to prolactin cells of a freshwater catfish, Heteropneustes fossilis

    Directory of Open Access Journals (Sweden)

    Diwakar Mishra

    2012-10-01

    Full Text Available In the present study, an organophosphorus compound Coroban (active ingredient chlorpyrifos – E.C. 20% was used. In short-term exposure the fish were subjected to 0.8 of 96h LC50 value of chlorpyrifos (1.76 mg L-1 for 96h. In long-term exposure the experiment was performed for 28 days by using 0.2 of 96h LC50 value of chlorpyrifos (0.44 mg L-1. Fish were killed on each time intervals from control and experimental (chlorpyrifos groups after 24, 48, 72, and 96h in short-term exposure and after 7, 14, 21, and 28 days in long-term experiment. Blood samples were collected and sera were analyzed for calcium. Pituitary glands were fixed for histological studies and stained with Herlant tetrachrome and Heidenhain’s azan techniques. Short-term exposure of chlorpyrifos caused decrease in the serum calcium levels. No change was noticed in the prolactin cells of chlorpyrifos treated fish. Long-term treatment with chlorpyrifos provoked hypocalcemia. The prolactin cells of treated fish exhibited slight degranulation after 21 days whereas the nuclear volume remained unchanged. After 28 days, the prolactin cells exhibited further degranulation and the nuclear volume recorded an increase. Cytolysis and vacuolization were also visible. No estudo presente, o composto organofosforo Coroban (ingrediente ativo clorpirifo – E.C. 20% foi usado. Na exposição a curto prazo os peixes foram submetido a 0,8 de valor LC50 de 96h de clorpirifo (1,76 mg L-1 durante 96h. Na exposição a longo prazo o experimento foi executado durante 28 dias usando 0,2 de valor LC50 de 96h de clorpirifos (0,44 mg L-1. Os peixes foram mortos a cada intervalo dos grupos controle e experimental (clorpirifos após 24, 48, 72, e 96h em exposição a curto prazo e após 7, 14, 21, e 28 dias no experimento a longo prazo. As amostras de sangue foram colhidas e o soro foi analisado para cálcio. As glândulas pituitárias foram fixadas para estudos histológicos e colorido por tetracromo de

  3. Kinetic investigation on the oxidation of tris(1,10-phenanthroline)iron(II) by oxone: the effect of BSA-SDS interaction.

    Science.gov (United States)

    Mandal, Harasit Kumar; Kundu, Arjama; Balti, Subrata; Mahapatra, Ambikesh

    2012-07-15

    The kinetic investigations of oxidation of tris(1,10-phenanthroline)iron(II) by oxone have been studied spectrophotometrically in phosphate buffer medium of pH 6.8, temperature 308 K, and ionic strength 0.25 mol L(-1). The reactions were also carried out in presence of globular transport protein, bovine serum albumin (BSA) having isoelectric point 4.9, anionic surfactant sodium dodecyl sulfate (SDS), and their mixtures. The critical aggregation concentration (CAC) and critical micelle concentration (CMC) of SDS in presence of BSA have been determined using conductivity and kinetic measurement techniques. The secondary structure of BSA was examined by Circular Dichroism (CD) measurement at 308 K. The helix nature of BSA decreases with increase of SDS concentration. The effect of pH on rate in presence of BSA is opposite to its absence, and the effect of urea on rate in presence of BSA indicates the denaturation of BSA. The results depict that amphiphile SDS interacts with BSA and different molecular events, for example, specific binding, cooperative binding, protein unfolding, and micelle formation act. Activation parameters of the reaction in different environments have been determined.

  4. Understanding the degradation pathway of the pesticide, chlorpyrifos by noble metal nanoparticles.

    Science.gov (United States)

    Bootharaju, M S; Pradeep, T

    2012-02-01

    Application of nanoparticles (NPs) in environmental remediation such as water purification requires a detailed understanding of the mechanistic aspects of the interaction between the species involved. Here, an attempt was made to understand the chemistry of noble metal nanoparticle-pesticide interaction, as these nanosystems are being used extensively for water purification. Our model pesticide, chlorpyrifos (CP), belonging to the organophosphorothioate group, is shown to decompose to 3,5,6-trichloro-2-pyridinol (TCP) and diethyl thiophosphate at room temperature over Ag and Au NPs, in supported and unsupported forms. The degradation products were characterized by absorption spectroscopy and electrospray ionization mass spectrometry (ESI MS). These were further confirmed by ESI tandem mass spectrometry. The interaction of CP with NP surfaces was investigated using transmission electron microscopy, energy dispersive analysis of X-rays, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). XPS reveals no change in the oxidation state of silver after the degradation of CP. It is proposed that the degradation of CP proceeds through the formation of AgNP-S surface complex, which is confirmed by Raman spectroscopy. In this complex, the P-O bond cleaves to yield a stable aromatic species, TCP. The rate of degradation of CP increases with increase of temperature and pH. Complete degradation of 10 mL of 2 ppm CP solution is achieved in 3 h using 100 mg of supported Ag@citrate NPs on neutral alumina at room temperature at a loading of ∼0.5 wt %. The effect of alumina and monolayer protection of NPs on the degradation of CP is also investigated. The rate of degradation of CP by Ag NPs is greater than that of Au NPs. The results have implications to the application of noble metal NPs for drinking water purification, as pesticide contamination is prevalent in many parts of the world. Study shows that supported Ag and Au NPs may be employed in sustainable

  5. Emblica officinalis Garten fruits extract ameliorates reproductive injury and oxidative testicular toxicity induced by chlorpyrifos in male rats

    OpenAIRE

    Dutta, Abir Lal; Sahu, Chitta Ranjan

    2013-01-01

    Organophosphate pesticides have destroying properties on male reproduction and chlorpyrifos adversely affects the male reproductive system. Emblica offcinalis Garten plays a vital role to challenge many diseases in human body. We investigated the induction of oxidative stress in the male reproductive system of adult rats (Wistar Strain) exposed to widely used organophosphate pesticide, Chlorpyrifos, and tried to establish the ameliorative properties of Emblica officinalis Garten with respect ...

  6. Transferable residues from dog fur and plasma cholinesterase inhibition in dogs treated with a flea control dip containing chlorpyrifos.

    OpenAIRE

    Boone, J S; Tyler, J. W.; Chambers, J. E.

    2001-01-01

    We studied chlorpyrifos, an insecticide present in a commercial dip for treating ectoparasites in dogs, to estimate the amount of transferable residues that children could obtain from their treated pets. Although the chlorpyrifos dip is no longer supported by the manufacturer, the methodology described herein can help determine transferable residues from other flea control insecticide formulations. Twelve dogs of different breeds and weights were dipped using the recommended guidelines with a...

  7. Production of a recombinant laccase from Pichia pastoris and biodegradation of chlorpyrifos in a laccase/vanillin system.

    Science.gov (United States)

    Xie, Huifang; Li, Qi; Wang, Minmin; Zhao, Linguo

    2013-06-28

    The recombinant strain P. pastoris GS115-lccC was used to produce laccase with high activity. Factors influencing laccase expression, such as pH, methanol concentration, copper concentration, peptone concentration, shaker rotate speed, and medium volume were investigated. Under the optimal conditions, laccase activity reached 12,344 U/L on day 15. The recombinant enzyme was purified by precipitating and dialyzing to electrophoretic homogeneity, and was estimated to have a molecular mass of about 58 kDa. When guaiacol was the substrate, the laccase showed the highest activity at pH 5.0 and was stable when the pH was 4.5~6.0. The optimal temperature for the laccase to oxidize guaiacol was 60°C, but it was not stable at high temperature. The enzyme could remain stable at 30°C for 5 days. The recombinant laccase was used to degrade chlorpyrifos in several laccase/mediator systems. Among three synthetic mediators (ABTS, HBT, VA) and three natural mediators (vanillin, 2,6-DMP, and guaiacol), vanillin showed the most enhancement on degradation of chlorpyrifos. Both laccase and vanillin were responsible for the degradation of chlorpyrifos. A higher dosage of vanillin may promote a higher level of degradation of chlorpyrifos, and the 2-step addition of vanillin led to 98% chlorpyrifos degradation. The degradation of chlorpyrifos was faster in the L/V system (kobs = 0.151) than that in the buffer solution (kobs = 0.028).

  8. Use of Bacillus thuringiensis supernatant from a fermentation process to improve bioremediation of chlorpyrifos in contaminated soils.

    Science.gov (United States)

    Aceves-Diez, Angel E; Estrada-Castañeda, Kelly J; Castañeda-Sandoval, Laura M

    2015-07-01

    The aim of this research was to investigate the potential of a nutrient-rich organic waste, namely the cell-free supernatant of Bacillus thuringiensis (BtS) gathered from fermentation, as a biostimulating agent to improve and sustain microbial populations and their enzymatic activities, thereby assisting in the bioremediation of chlorpyrifos-contaminated soil at a high dose (70 mg kg(-1)). Experiments were performed for up to 80 d. Chlorpyrifos degradation and its major metabolic product, 3,5,6-trichloro-2-pyridinol (TCP), were quantified by high-performance liquid chromatography (HPLC); total microbial populations were enumerated by direct counts in specific medium; and fluorescein diacetate (FDA) hydrolysis was measured as an index of soil microbial activity. Throughout the experiment, there was higher chlorpyrifos degradation in soil supplemented with BtS (83.1%) as compared to non-supplemented soil. TCP formation and degradation occurred in all soils, but the greatest degradation (30.34%) was observed in soil supplemented with BtS. The total microbial populations were significantly improved by supplementation with BtS. The application of chlorpyrifos to soil inhibited the enzymatic activity; however, this negative effect was counteracted by BtS, inducing an increase of approximately 16% in FDA hydrolysis. These results demonstrate the potential of B. thuringiensis supernatant as a suitable biostimulation agent for enhancing chlorpyrifos and TCP biodegradation in chlorpyrifos-contaminated soils.

  9. Changes of field incurred chlorpyrifos and its toxic metabolite residues in rice during food processing from-RAC-to-consumption.

    Science.gov (United States)

    Zhang, Zhiyong; Jiang, Wayne W; Jian, Qiu; Song, Wencheng; Zheng, Zuntao; Wang, Donglan; Liu, Xianjin

    2015-01-01

    The objectives of this study were to determine the effects of food processing on field incurred residues levels of chlorpyrifos and its metabolite 3,5,6-Trichloro-2-pyridinol (TCP) in rice. The chlorpyrifos and TCP were found to be 1.27 and 0.093 mg kg-1 in straw and 0.41 and 0.073 mg kg-1 in grain, respectively. It is observed that the sunlight for 2 hours does not decrease the chlorpyrifos and TCP residues in grain significantly. Their residues in rice were reduced by up to 50% by hulling. The cooking reduced the chlorpyrifos and TCP in rice to undetectable level (below 0.01 mg kg-1). Processing factors (PFs) of chlorpyrifos and TCP residues in rice during food processing were similar. Various factors have impacts on the fates of chlorpyrifos and TCP residues and the important steps to reduce their residues in rice were hulling and cooking. The results can contribute to assure the consumer of a safe wholesome food supply.

  10. The expression profile of detoxifying enzyme of tomato leaf miner, Tuta absoluta Meyrik (Lepidoptera: Gelechiidae to chlorpyrifos

    Directory of Open Access Journals (Sweden)

    Idin Zibaee

    2016-06-01

    Full Text Available The tomato leafminer, Tuta absoluta (Meyrich (Lepidoptera: Gelechiidae is an important pest of tomato crops worldwide. The persistent use of organophosphate insecticide to control this pest has led to resistance. However, there is no report on the susceptibility and resistance mechanism of field population of Tuta absoluta (Meyrik from Iran. Furthermore, the toxicity and impact of chlorpyrifos on metabolic enzymes in this pest remains unknown. The populations of T. absoluta from Rasht in Iran displayed LC30; 4332, LC50; 5010 and LC90; 7027 μg larva-1 to chlorpyrifos. The toxicity of chlorpyrifos could be synergized more bydiethyl maleate (DEM and triphenylphosphate (TPP whereas the synergistic effect of piperonylbutoxide (PBO was not efficient as well as two other synergists. The synergistic effect ranged from 1.3 to 1.9-fold in 24 h and 1.2 to 1.5-fold in 48 h. The exposure with chlorpyrifos for 24 and 48 h significantly increased the activities of esterase and cytochrome P450-dependent monooxygenases, while there were no significant changes in glutathione-S-transferase. Field populations of T. absoluta from Iran displayed less susceptibility to chlorpyrifos and had a relatively high LC50 in compare to other previous studies. Esterases and cytochrome P450 monooxygenase might be involved in the metabolism, and hence resistance to, chlorpyrifos in this pest.

  11. Electrochemical Determination of Chlorpyrifos on a Nano-TiO₂Cellulose Acetate Composite Modified Glassy Carbon Electrode.

    Science.gov (United States)

    Kumaravel, Ammasai; Chandrasekaran, Maruthai

    2015-07-15

    A rapid and simple method of determination of chlorpyrifos is important in environmental monitoring and quality control. Electrochemical methods for the determination of pesticides are fast, sensitive, reproducible, and cost-effective. The key factor in electrochemical methods is the choice of suitable electrode materials. The electrode materials should have good stability, reproducibility, more sensitivity, and easy method of preparation. Mercury-based electrodes have been widely used for the determination of chlorpyrifos. From an environmental point of view mercury cannot be used. In this study a biocompatible nano-TiO2/cellulose acetate modified glassy carbon electrode was prepared by a simple method and used for the electrochemical sensing of chlorpyrifos in aqueous methanolic solution. Electroanalytical techniques such as cyclic voltammetry, differential pulse voltammetry, and amperometry were used in this work. This electrode showed very good stability, reproducibility, and sensitivity. A well-defined peak was obtained for the reduction of chlorpyrifos in cyclic voltammetry and differential pulse voltammetry. A smooth noise-free current response was obtained in amperometric analysis. The peak current obtained was proportional to the concentration of chlorpyrifos and was used to determine the unknown concentration of chlorpyrifos in the samples. Analytical parameters such as LOD, LOQ, and linear range were estimated. Analysis of real samples was also carried out. The results were validated through HPLC. This composite electrode can be used as an alternative to mercury electrodes reported in the literature.

  12. Application of a mathematical model to describe the effects of chlorpyrifos on Caenorhabditis elegans development.

    Directory of Open Access Journals (Sweden)

    Windy A Boyd

    Full Text Available BACKGROUND: The nematode Caenorhabditis elegans is being assessed as an alternative model organism as part of an interagency effort to develop better means to test potentially toxic substances. As part of this effort, assays that use the COPAS Biosort flow sorting technology to record optical measurements (time of flight (TOF and extinction (EXT of individual nematodes under various chemical exposure conditions are being developed. A mathematical model has been created that uses Biosort data to quantitatively and qualitatively describe C. elegans growth, and link changes in growth rates to biological events. Chlorpyrifos, an organophosphate pesticide known to cause developmental delays and malformations in mammals, was used as a model toxicant to test the applicability of the growth model for in vivo toxicological testing. METHODOLOGY/PRINCIPAL FINDINGS: L1 larval nematodes were exposed to a range of sub-lethal chlorpyrifos concentrations (0-75 microM and measured every 12 h. In the absence of toxicant, C. elegans matured from L1s to gravid adults by 60 h. A mathematical model was used to estimate nematode size distributions at various times. Mathematical modeling of the distributions allowed the number of measured nematodes and log(EXT and log(TOF growth rates to be estimated. The model revealed three distinct growth phases. The points at which estimated growth rates changed (change points were constant across the ten chlorpyrifos concentrations. Concentration response curves with respect to several model-estimated quantities (numbers of measured nematodes, mean log(TOF and log(EXT, growth rates, and time to reach change points showed a significant decrease in C. elegans growth with increasing chlorpyrifos concentration. CONCLUSIONS: Effects of chlorpyrifos on C. elegans growth and development were mathematically modeled. Statistical tests confirmed a significant concentration effect on several model endpoints. This confirmed that chlorpyrifos

  13. Effect of processing on residues of 14C-chlorpyrifos in coconut oil

    International Nuclear Information System (INIS)

    A coconut tree was root infused with 5 g of 14C-chlorpyrifos (51.8 kBq) and residues in the young and mature fruits were determined at various intervals up to 60 days. After 2 months the mature fruits retained much higher residues in the meat (11 mg/kg) than the young fruit (0.6 mg/kg). Under simulated agricultural practice, a post harvest single treatment of mature coconut meat (copra) resulted in a mean residue value of 8.2 mg/kg copra meat after three months. After gaining the crude oil by extraction with n-hexane, the efficiency of processes used commercially in refining the oil were tested. For post harvest treatment, aged residues lost only 23% after subjecting the crude oil to alkali treatment, bleaching and steam distillation, while chlorpyrifos-spiked samples lost 30%. (author). 5 refs, 3 tabs

  14. Synthesis and Characterization of Microcapsules with Chlorpyrifos Cores and Polyurea Walls

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interfacial polycondensation reaction.The products were characterized by means of Fourier transform infrared spectrometry, 13C NMR spectrometry and 31P NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.

  15. In vitro protection of human lymphocytes from toxic effects of chlorpyrifos by selenium-enriched medicines

    OpenAIRE

    Navaei-Nigjeh, Mona; Asadi, Hamidreza; Baeeri, Maryam; Pedram, Sahar; Rezvanfar, Mohammad Amin; Mohammadirad, Azadeh; Abdollahi, Mohammad

    2015-01-01

    Objective(s): Chlorpyrifos (CP) is a broad-spectrum organophosphorus pesticide used extensively in agricultural and domestic pest control, accounting for 50% of the global insecticidal use. In the present study, protective effects of two selenium-enriched strong antioxidative medicines IMOD and Angipars were examined in human lymphocytes treated with CP in vitro. Materials and Methods: Isolated lymphocytes were exposed to 12 µg/ml CP either alone or in combination with effective doses (ED50) ...

  16. Environmental distribution of acetochlor, atrazine, chlorpyrifos, and propisochlor under field conditions.

    Science.gov (United States)

    Konda, L N; Pásztor, Z

    2001-08-01

    The environmental behavior, movement, distribution, persistence, and runoff by rainfall of the pesticides acetochlor, atrazine, chlorpyrifos, and propisochlor were studied under field conditions during a five-month period at normal weather conditions. The pesticide concentrations in soil depths of 0-5 and 5-20 cm, and in sediment and runoff water samples (collected from an artificial reservoir built in the lower part of the experimental plot) were measured every second week and following every runoff event. The contamination of a stream running across the lowest part of the plot was also monitored. The weather conditions were also recorded at the experimental site. The pesticide residues were quantified by a capillary gas chromatograph equipped with a nitrogen phosphorus selective detector (GC-NPD). There was a consistent decrease in pesticide residues in the 0-5 cm soil layer with time after spaying. At 140 days after treatment only atrazine and chlorpyrifos were present; acetochlor and propisochlor were not detected in this soil layer. Atrazine and chlorpyrifos in the soil at a depth of 5-20 cm were detectable during the whole experimental interval, whereas acetochlor and propisochlor concentrations were below the limit of detection. Pesticide losses by the surface runoff process and the contamination of the stream were closely related to the time of rainfall elapsed after treatment and amount of rain at the experimental plots. Losses were primarily dependent on surface rainfall volume and intensity. The maximum detected residues of atrazine and acetochlor in stream water were 1 order of magnitude higher than the maximum residue limit specified by the European Union (EU) for environmental and drinking water (0.1 microg/L for individual compounds and 0.5 microg/L for total pesticides). Chlorpyrifos and propisochlor were not detected in this matrix. PMID:11513679

  17. Genotoxic Effects of Chlorpyrifos in Freshwater Fish Cirrhinus mrigala Using Micronucleus Assay

    OpenAIRE

    Anita Bhatnagar; Abhay Singh Yadav; Navneet Cheema

    2016-01-01

    The genotoxicity of pesticides is an issue of worldwide concern and chlorpyrifos is one of the largest selling organophosphate agrochemicals that has been widely detected in surface waters of India. The studies on long term genotoxic biomarkers are limited; therefore, present study was carried out to analyze the incidence of nuclear anomalies in the blood cells of fresh water fish Cirrhinus mrigala using micronucleus (MN) assay as a potential tool for assessment of genotoxicity. Acute toxicit...

  18. Prenatal chlorpyrifos exposure alters motor behavior and ultrasonic vocalization in cd-1 mouse pups

    OpenAIRE

    Calamandrei Gemma; Scattoni Maria; Ricceri Laura; Venerosi Aldina

    2009-01-01

    Abstract Background Chlorpyrifos (CPF) is a non-persistent organophosphate (OP) largely used as pesticide. Studies from animal models indicate that CPF is a developmental neurotoxicant able to target immature central nervous system at dose levels well below the threshold of systemic toxicity. So far, few data are available on the potential short- and long-term adverse effects in children deriving from low-level exposures during prenatal life and infancy. Methods Late gestational exposure [ges...

  19. Effects of chlorpyrifos, carbendazim and linuron on the ecology of a small indoor aquatic microcosm

    OpenAIRE

    Daam, M.A.; Brink, van den, R.B.A.

    2007-01-01

    To validate the use of small indoor microcosms for the risk assessment of pesticides, the fate and effects of chlorpyrifos, carbendazim, and linuron were studied in 8.5¿liter indoor freshwater microcosms. Functional and structural responses to selected concentrations were evaluated and compared with responses observed in larger-scale model ecosystem studies. Overall, the microcosms adequately displayed the chain of effects resulting from the application, although they did not always predict t...

  20. Efficiency of the intestinal bacteria in the degradation of the toxic pesticide, chlorpyrifos

    OpenAIRE

    Harishankar, M. K.; C Sasikala; Ramya, M.

    2012-01-01

    Chlorpyrifos (CP) is the most commonly used pesticide throughout the world. Its widespread use in agriculture and its potential toxicity to humans from ingestion of CP contaminated food have raised concerns about its risk to health. Human intestinal microflora has the ability to degrade pesticides, but the exact mechanisms involved and the metabolite end-products formed are not well understood. The primary objective of this work was to analyse the in vitro degradation of CP by five model inte...

  1. Developmental neurotoxic effects of two pesticides : behavior and biomolecular studies on chlorpyrifos and carbaryl

    OpenAIRE

    Lee, Iwa; Eriksson, Per; Fredriksson, Anders; Buratovic, Sonja; Viberg, Henrik

    2015-01-01

    In recent times, an increased occurrence of neurodevelopmental disorders, such as neurodevelopmental delays and cognitive abnormalities has been recognized. Exposure to pesticides has been suspected to be a possible cause of these disorders, as these compounds target the nervous system of pests. Due to the similarities of brain development and composition, these pesticides may also be neurotoxic to humans. We studied two different pesticides, chlorpyrifos and carbaryl, which specifically inhi...

  2. PON1 Status Does Not Influence Cholinesterase Activity in Egyptian Agricultural Workers Exposed to Chlorpyrifos

    OpenAIRE

    Ellison, Corie A.; Crane, Alice L.; Bonner, Matthew R; Knaak, James B.; Browne, Richard W; Lein, Pamela J; Olson, James R.

    2012-01-01

    Animal studies have shown that paraoxonase 1 (PON1) genotype can influence susceptibility to the organophosphorus pesticide chlorpyrifos (CPF). However, Monte Carlo analysis suggests that PON1 genotype may not affect CPF-related toxicity at low exposure conditions in humans. The current study sought to determine the influence of PON1 genotype on the activity of blood cholinesterase as well as the effect of CPF exposure on serum PON1 in workers occupationally exposed to CPF. Saliva, blood and ...

  3. Sub-lethal Effects of Chlorpyrifos on Big Brown Bats (Eptesicus fuscus).

    Science.gov (United States)

    Eidels, Ronny R; Sparks, Daniel W; Whitaker, John O; Sprague, Charles A

    2016-10-01

    We determined dose-response curves for sublethal effects of the organophosphorus (OP) insecticide, chlorpyrifos, on bats. Big brown bats (Eptesicus fuscus, n = 64) were given a single dose of chlorpyrifos (nominal concentrations) of 0, 5, 10, 15, 20, 25, 30, or 60 µg/g body weight and examined at 12 or 24 h after dosing. A second experiment dosed 32 bats with 0 or 60 µg/g body weight and examined 1, 3, 7, or 14 days after dosing. Skin temperature and behavioral changes were recorded, and brain and plasma cholinesterase (ChE) activity were measured. The benchmark dose (BMD10) of chlorpyrifos that altered brain and plasma ChE activity at 24 h was 3.7 and 10.1 µg/g, respectively. The 95 % lower confidence limit for the BMD10 (i.e., BMDL10) was 1.6 and 7.7 µg/g. The best of five models (as determined by AIC) for impaired flight, impaired movement, or presence of tremors provided a BMD10 of 6.2, 12.9, and 7.8 µg/g body weight of chlorpyrifos, respectively. BMDL10 for impaired flight, impaired movement, or presence of tremors was 3.5, 6.6, and 5.3 µg/g body weight, respectively. In the wild, impaired ability to fly or crawl could be life-threatening. Brain and plasma ChE activity remained low for 3 days after dosing. Gradual recovery of enzyme activity was observed by 7 days in survivors. Brain and plasma ChE activity were still significantly lower than that of the control group at 14 days after dosing. PMID:27491870

  4. Impact of single and repeated applications of the insecticide chlorpyrifos on tropical freshwater plankton communities.

    Science.gov (United States)

    Daam, Michiel A; Van den Brink, Paul J; Nogueira, António J A

    2008-11-01

    This paper describes the effects of a single and a repeated application of the organophosphorus insecticide chlorpyrifos on zooplankton and phytoplankton communities in outdoor microcosms in Thailand. Treatment levels of 1 microg L(-1) were applied once or twice with a 2-week interval. Both treatments led to a significant decrease in cladocerans followed by an increase in rotifers, although the extent by which species were affected was different. Ceriodaphnia cornuta was the most responding cladoceran after the first treatment, while Moina micrura responded most to the second. This is explained by differences in the growth phase of M. micrura at the time of application and an increase in Microcystis abundance over the course of the experiment. Several phytoplankton taxa either increased or decreased as a result of the chlorpyrifos-induced changes in zooplankton communities. Even though chlorpyrifos disappeared fast from the water column, effects on plankton communities persisted till the end of the experiment (42 days) when the insecticide concentrations had dropped below the detection limit. This was presumably due to the increasing population trend of Microcystis, favouring rotifers over cladocerans. PMID:18498053

  5. In-residence, multiple route exposures to chlorpyrifos and diazinon estimated by indirect method models

    Science.gov (United States)

    Moschandreas, D. J.; Kim, Y.; Karuchit, S.; Ari, H.; Lebowitz, M. D.; O'Rourke, M. K.; Gordon, S.; Robertson, G.

    One of the objectives of the National Human Exposure Assessment Survey (NHEXAS) is to estimate exposures to several pollutants in multiple media and determine their distributions for the population of Arizona. This paper presents modeling methods used to estimate exposure distributions of chlorpyrifos and diazinon in the residential microenvironment using the database generated in Arizona (NHEXAS-AZ). A four-stage probability sampling design was used for sample selection. Exposures to pesticides were estimated using the indirect method of exposure calculation by combining measured concentrations of the two pesticides in multiple media with questionnaire information such as time subjects spent indoors, dietary and non-dietary items they consumed, and areas they touched. Most distributions of in-residence exposure to chlorpyrifos and diazinon were log-normal or nearly log-normal. Exposures to chlorpyrifos and diazinon vary by pesticide and route as well as by various demographic characteristics of the subjects. Comparisons of exposure to pesticides were investigated among subgroups of demographic categories, including gender, age, minority status, education, family income, household dwelling type, year the dwelling was built, pesticide use, and carpeted areas within dwellings. Residents with large carpeted areas within their dwellings have higher exposures to both pesticides for all routes than those in less carpet-covered areas. Depending on the route, several other determinants of exposure to pesticides were identified, but a clear pattern could not be established regarding the exposure differences between several subpopulation groups.

  6. Effects of Nickel, Chlorpyrifos and Their Mixture on the Dictyostelium discoideum Proteome

    Directory of Open Access Journals (Sweden)

    Francesco Marsano

    2012-11-01

    Full Text Available Mixtures of chemicals can have additive, synergistic or antagonistic interactions. We investigated the effects of the exposure to nickel, the organophosphate insecticide chlorpyrifos at effect concentrations (EC of 25% and 50% and their binary mixture (Ec25 + EC25 on Dictyostelium discoideum amoebae based on lysosomal membrane stability (LMS. We treated D. discoideum with these compounds under controlled laboratory conditions and evaluated the changes in protein levels using a two-dimensional gel electrophoresis (2DE proteomic approach. Nickel treatment at EC25 induced changes in 14 protein spots, 12 of which were down-regulated. Treatment with nickel at EC50 resulted in changes in 15 spots, 10 of which were down-regulated. Treatment with chlorpyrifos at EC25 induced changes in six spots, all of which were down-regulated; treatment with chlorpyrifos at EC50 induced changes in 13 spots, five of which were down-regulated. The mixture corresponding to EC25 of each compound induced changes in 19 spots, 13 of which were down-regulated. The data together reveal that a different protein expression signature exists for each treatment, and that only a few proteins are modulated in multiple different treatments. For a simple binary mixture, the proteomic response does not allow for the identification of each toxicant. The protein spots that showed significant differences were identified by mass spectrometry, which revealed modulations of proteins involved in metal detoxification, stress adaptation, the oxidative stress response and other cellular processes.

  7. Bird predation on cutworms (Lepidoptera: Noctuidae) in wheat fields and chlorpyrifos effects on brain cholinesterase activity

    Science.gov (United States)

    McEwen, L.C.; DeWeese, L.R.; Schladweiler, P.

    1986-01-01

    Horned larks, Eremophila alpestris (L.), and McCown's longspurs, Calcarius mccownii (Lawrence), were collected at intervals from two winter wheat fields in Montana [USA] after aerial application of chlorpyrifos to control cutworms. Both bird species had a high (95-100%) incidence of Lepidoptera, mostly pale western cutworms, Agrotis orthogonia Morrison, in their stomachs at 3 days postspray. Incidence of cutworms and other insects in stomachs of birds from sprayed fields was lower at 9 and 16 days postspray than in control birds, presumably due to insecticide-caused reduction of insects. Effects of birds on population dynamics of insect pests in wheat are unknown, but birds do contribute to cutworm mortality. Predation is one of the limiting factors to cutworm increase and can supplement insecticidal control. Brain cholinesterase activity in horned larks collected from the sprayed fields at 3 and 9 days postspray was significantly lower than in unexposed larks, but at 16 days the difference was not significant. Although nontarget birds clearly were exposed to chlorpyrifos and manifested a sublethal physiological response, toxic effects were less severe than those resulting from endrin application for cutworm control in wheat. More study is needed of larger chlorpyrifos-treated fields under a variety of conditions to fully assess effects on nontarget life.

  8. A comparison of a laboratory scale experiment with a field trial treatment using chlorpyrifos-methyl

    International Nuclear Information System (INIS)

    An experiment was carried out in which a field treatment of a small bulk of grain with chlorpyrifos-methyl was compared with a laboratory treatment of 1 kg of grain with 14C radiolabelled chlorpyrifos-methyl. The conditions under which the grain was maintained in the laboratory mimicked those of the field trial as closely as possible, with sampling and analysis being carried out at the same time and in a similar manner in both. The results from the two experiments were in general agreement with approx. 60% of the chlorpyrifos-methyl remaining intact at the end. A satisfactory level of biological control was achieved in the field trial. The use of the radio-label enabled more information about the fate of the degraded insecticide to be obtained from the laboratory experiment. The majority of this radioactivity comprised a fraction which remained within the grain tissue after solvent extraction. The level of activity in the grain tissues gradually increased with time but its nature is as yet unknown. The good agreement obtained between the residue profile and the breakdown patterns in both experiments would suggest that a laboratory scale experiment is a satisfactory model for the situation pertaining in a large scale field trial. (author)

  9. Ce/SBA-15联合Oxone去除水中染料RhB的试验研究%Experimental study on RhB removal from aqueous solution by Ce/SBA-15 combined with oxone

    Institute of Scientific and Technical Information of China (English)

    许丹丹

    2014-01-01

    将负载型的Ce∕SBA-15与过硫酸氢钾复合盐(Oxone)联合,考察了该联合体系对染料罗丹明B(RhB)的去除效果。结果表明:该体系中RhB的去除符合准一级动力学方程,提高Ce∕SBA-15和Oxone投加量,降低初始RhB浓度和提高反应温度会增强RhB的去除效果,未调节溶液初始pH值时, RhB的去除效果最好。制备的Ce∕SBA-15在5次循环使用后仍具有约80%的RhB去除率, RhB的去除机制为表面吸附催化。 Ce∕SBA-15与Oxone联合产生以硫酸根自由基为主的处理技术对难降解污染物质具有潜在的实际应用价值。%The effect of supported Ce/SBA-15-oxone combined system on Rhodamine B removal from aqueous solution was investigated. The results showed that, the process of RhB removal followed pseudo-first or‐der kinetics equation, the removal rate of RhB increased with increasing Ce/SBA-15 and oxone dosage, reaction temperature and decreasing initial RhB concentration. The maximum removal efficiency was achieved under the condition that the initial pH value of the solution was unjusted. The material Ce/SBA-15 possessed good reusability, and when reused up to 5 cycles, the removal rate of RhB by it could still maintained at about 80%. The mechanism of RhB removal was surface adsorption and catalysis. It could draw a conclusion that, the com‐bined process of Ce/SBA-15-oxone which could generate sulfate radicals had potential application value in the field of hard-degradable pollutants treatment.

  10. Determination of 3,5,6-trichloro-2-pyridinol levels in the urine of termite control workers using chlorpyrifos.

    Directory of Open Access Journals (Sweden)

    Jitsunari,Fumihiko

    1989-10-01

    Full Text Available Chlorpyrifos, an organophosphorus insecticide, has been used to control termites since regulatory measures against the use of chlordanes were taken in September, 1986. We developed an improved gas chromatographic (GC method for the assay of 3,5,6-trichloro-2-pyridinol (TCP in the urine to use in the biological monitoring of exposure to chlorpyrifos. Urinary TCP was separated and determined accurately (C.V., 4% with high sensitivity (detection limit, 10 ng/ml and recovery (recovery greater than 90% using a wide bore capillary column (WBC column. The accuracy and precision of the present GC method are satisfactory. The time course of urinary excretion of TCP was followed in workers. The urinary TCP level was low in the off-season and high in the busy season. Variation in the urinary TCP level corresponded to the termite control season and the length of the working period. The urinary TCP level showed a change reciprocal to the variations in the plasma cholinesterase activity. From these results, it is surmised that the urinary TCP level represents the extent of exposure to chlorpyrifos. The decrease in the level of cholinesterase activity is suggested to be due to exposure to chlorpyrifos. Determination of the urinary TCP level by GC using a WBC column is useful in the biological monitoring of chlorpyrifos in termite control workers and potentially has practical application to health care.

  11. Indigenous children nearby plantations with chlorpyrifos-treated bags have elevated 3,5,6-trichloro-2-pyridinol (TCPy) urinary concentrations

    NARCIS (Netherlands)

    Wendel de Joode, van B.; Barraza-Ruiz, D.A.; Ruepert, C.; Mora, A.M.; Córdoba, L.; Öberg, M.; Wesseling, C.; Mergler, D.; Lindh, C.

    2012-01-01

    BACKGROUND: The US Environmental Protection Agency voluntary phased-out residential use of chlorpyrifos in 2001. In contrast, in Costa Rica, chlorpyrifos-treated bags are increasingly used to protect banana and plantain fruits from insects and to fulfill product standards, even in populated areas. O

  12. Effects of the insecticide Dursban 4E (active ingredient chlorpyrifos) in outdoor experimental ditches: I. comparison of short-term toxicity between the laboratory and the field

    NARCIS (Netherlands)

    Wijngaarden, van R.P.A.; Brink, van den P.J.; Crum, S.J.H.; Oude Voshaar, J.H.; Brock, T.C.M.; Leeuwangh, P.

    1996-01-01

    By means of the insecticide chlorpyrifos, results of acute single-species toxicity tests were compared with direct effects in outdoor mesocosms. In the mesocosms, chlorpyrifos concentrations between 0.1 and 44 Šg/l were sprayed once. Acute effects were observed on arthropods. Effects could be quanti

  13. Children's residential exposure to chlorpyrifos: Application of CPPAES field measurements of chlorpyrifos and TCPy within MENTOR/SHEDS-Pesticides model

    Energy Technology Data Exchange (ETDEWEB)

    Hore, Paromita [Environmental and Occupational Health Sciences Institute (EOHSI), Rutgers University and the University of Medicine and Dentistry of New Jersey (UMDNJ), Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08855 (United States)]|[New York City Department of Health, 253 Broadway New York, New York 10007 (United States); Zartarian, Valerie; Xue Jianping; Ozkaynak, Haluk [National Exposure Research Laboratory, U.S. EPA, 109 TW Alexander Drive, Research Triangle Park, NC 27709 (United States); Wang, S.-W.; Yang, Y.-C.; Chu, P.-Ling; Robson, Mark; Georgopoulos, Panos [Environmental and Occupational Health Sciences Institute (EOHSI), Rutgers University and the University of Medicine and Dentistry of New Jersey (UMDNJ), Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08855 (United States); Sheldon, Linda [National Exposure Research Laboratory, U.S. EPA, 109 TW Alexander Drive, Research Triangle Park, NC 27709 (United States); Needham, Larry Barr, Dana [Contemporary Pesticide Laboratory, Centers for Disease Control, 4770 Buford Highway, Atlanta, GA 30341 (United States); Freeman, Natalie [Environmental and Occupational Health Sciences Institute (EOHSI), Rutgers University and the University of Medicine and Dentistry of New Jersey (UMDNJ), Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08855 (United States)]|[University of Florida, Gainesville, FL 32611 (United States); Lioy, Paul J. [Environmental and Occupational Health Sciences Institute (EOHSI), Rutgers University and the University of Medicine and Dentistry of New Jersey (UMDNJ), Robert Wood Johnson Medical School, 170 Frelinghuysen Road, Piscataway, NJ 08855 (United States)]. E-mail: plioy@eohsi.rutgers.edu

    2006-08-01

    The comprehensive individual field-measurements on non-dietary exposure collected in the Children's-Post-Pesticide-Application-Exposure-Study (CPPAES) were used within MENTOR/SHEDS-Pesticides, a physically based stochastic human exposure and dose model. In this application, however, the model was run deterministically. The MENTOR/SHEDS-Pesticides employed the CPPAES as input variables to simulate the exposure and the dose profiles for seven children over a 2-week post-application period following a routine residential and professional indoor crack-and-crevice chlorpyrifos application. The input variables were obtained from a personal activity diary, microenvironmental measurements and personal biomonitoring data obtained from CPPAES samples collected from the individual children and in their homes. Simulation results were compared with CPPAES field measured values obtained from the children's homes to assess the utility of the different microenvironmental data collected in CPPAES, i.e. indicator toys and wipe samplers to estimate aggregate exposures that can be result from one or more exposure pathways and routes. The final analyses of the database involved comparisons of the actual data obtained from the individual biomarker samples of a urinary metabolite of chlorpyrifos (TCPy) and the values predicted by MENTOR/SHEDS-Pesticides using the CPPAES-derived variables. Because duplicate diet samples were not part of the CPPAES study design, SHEDs-Pesticides simulated dose profiles did not account for the dietary route. The research provided more confidence in the types of data that can be used in the inhalation and dermal contact modules of MENTOR/SHEDS-Pesticides to predict the pesticide dose received by a child. It was determined that we still need additional understanding about: (1) the types of activities and durations of activities that result in non-dietary ingestion of pesticides and (2) the influence of dietary exposures on the levels of TCPy found

  14. Chlorpyrifos-induced Histopathological Alterations in Duttaphrynus melanostictus (Schneider 1799 Tadpoles: Evidence from Empirical Trials

    Directory of Open Access Journals (Sweden)

    M. G. D. K. Bandara

    2012-10-01

    Full Text Available This paper reports the histopathological responses of the gill, liver and tail muscle tissues in tadpoles of the Asian Common Toad Duttaphrynus melanostictus (Schneider, 1799 exposed to chlorpyrifos a common organophosphorus pesticide. Tadpoles of Gosner stages 24-26 were continuously exposed to low, mid and high (500, 1000 and 1500 µgl–1 concentrations of chlorpyrifos for two weeks. Histological alterations in the tissues of the surviving larvae were microscopically examined both at the end of the exposure period and after a week following the final exposure. Several histological alterations were noted in the gills, liver and tail muscles of the larvae exposed to 1500 µgl–1 of chlorpyrifos. The gills of exposed larvae showed architectural distortion resulting from reduced primary and secondary gill lamellae and blood vessels, and alterations in the gill epithelium. In the liver sinusoidal congestion and dilation, cytoplasmic vacuolation and changes in hepatocytes such as hyperchromatic nuclei and nuclear fragmentation were observed.  The tail muscle tissue suffered from severe atrophy and myotomal disintegration. Although histological alterations in the gill and liver tissues were noted only at the high concentration, changes in the muscle tissue i.e. muscle degeneration and atrophy, were apparent at both low and mid concentrations. The degree of damage in surviving larvae in a week following the final exposure was lower than that observed during the exposure, probably indicating recovery or resistance. The findings of the present study emphasize the need to investigate possible sublethal damage induced by pesticides in amphibians inhabiting agricultural habitats.

  15. Degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution by TiO2 photocatalysis.

    Science.gov (United States)

    Affam, Augustine Chioma; Chaudhuri, Malay

    2013-11-30

    Degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution by TiO2 photocatalysis under UVA (365 nm) irradiation was examined. Enhancement of degradation and improvement in biodegradability index (BOD5/COD ratio) by H2O2 addition were also evaluated. UVA irradiation per se produced insignificant degradation of the pesticides. In UV/TiO2 photocatalysis (TiO2 1.5 g L(-1), pH 6 and 300 min irradiation), COD and TOC removal were 25.95 and 8.45%, respectively. In UV/TiO2/H2O2 photocatalysis (TiO2 1.5 g L(-1), H2O2 100 mg L(-1), pH 6 and 300 min irradiation), COD and TOC removal were 53.62 and 21.54%, respectively and biodegradability index improved to 0.26. Ammonia-nitrogen (NH3-N) decreased from 22 to 7.8 mg L(-1) and nitrate-nitrogen (NO3(-)-N) increased from 0.7 to 13.8 mg L(-1) in 300 min, indicating mineralization. Photocatalytic degradation followed pseudo-first order kinetics with rate constant (k) of 0.0025 and 0.0008 min(-1) for COD and TOC removal, respectively. FTIR spectra indicated degradation of the organic bonds of the pesticides. UV/TiO2/H2O2 photocatalysis is effective in degradation of pesticides chlorpyrifos, cypermethrin and chlorothalonil in aqueous solution. UV/TiO2/H2O2 photocatalysis may be applied as pretreatment of a chlorpyrifos, cypermethrin and chlorothalonil pesticide wastewater at pH 6, for biological treatment.

  16. Acute toxicity of chlorpyrifos, cadusafos and diazinon to three Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fingerlings

    OpenAIRE

    Hossain, Z; Haldar, G.C.; Mollah, M.F.A.

    2000-01-01

    Fingerlings of three Indian major carps, viz. Catla catla (Hamilton-Buchanon), Labeo rohita (Hamilton-Buchanon) and Cirrhinus mrigala (Hamilton-Buchanon), were exposed to different concentrations of chlorpyrifos (lorsban 10 G), cadusafos (rugby 10 G) and diazinon (basudin 10 G) for a period of 96h with a view to determine the median lethal concentrations (LC sub50) values for each of chemicals. Of the tested concentrations, chlorpyrifos at a dose of 6.65 ppm, cadusafos at 2.0 ppm and diazinon...

  17. Effect of Different Administration Paradigms on Cholinesterase Inhibition following Repeated Chlorpyrifos Exposure in Late Preweanling Rats

    OpenAIRE

    Carr, Russell L.; Nail, Carole A.

    2008-01-01

    Chlorpyrifos (CPS) is widely used in agricultural settings and residue analysis has suggested that children in agricultural communities are at risk of exposure. This has resulted in a large amount of literature investigating the potential for CPS-induced developmental neurotoxic effects. Two developmental routes of administration of CPS are orally in corn oil at a rate of 0.5 ml/kg and subcutaneously in dimethyl sulfoxide (DMSO) at a rate of 1.0 ml/kg. For comparison between these methods, ra...

  18. Energetic Cost of Subacute Chlorpyrifos Intoxication in the German Cockroach (Dictyoptera: Blattellidae)

    DEFF Research Database (Denmark)

    Nielsen, Søren Achim; Jensen, Karl-Martin Vagn; Kristensen, Michael;

    2006-01-01

    The energetic cost of a sublethal treatment with chlorpyrifos was estimated by use of direct microcalorimetry to measure metabolic heat in susceptible and resistant strains of the German cockroach Blattella germanica L. Moreover, one of the detoxifcation enzyme systems known to be involved...... production increased in the susceptible strain ...  30 min after exposure and declined again after ... 120 min to the basal level. The energetic cost of the exposure to the insecticide corresponds ... 5 h of normal metabolism. There were no signifcant differences in heat production after toxic treatment...

  19. Cold Stress Offered Modulation on Chlorpyrifos Toxicity in Aging Rat Central Nervous System

    OpenAIRE

    Basha, Mahaboob; Poojary, Annappa

    2012-01-01

    The adverse effects produced by chlorpyrifos (CPF) or cold stress alone in humans and animals are well documented, but there is no information available relating to the consequences of their co- exposure in an age-related manner. In this study, effects of sublethal doses of CPF were carried out in vivo, for 48 h to assess the biochemical perturbations in relation to interactions with cold stress (15°C and 20°C) in different age group rat CNS. A positive interaction of CPF with age of animal a...

  20. Swimming impairment and acetylcholinesterase inhibition in zebrafish exposed to copper or chlorpyrifos separately, or as mixtures

    OpenAIRE

    Tilton, Fred A.; Bammler, Theo K.; Gallagher, Evan P.

    2010-01-01

    Pesticides such as chlorpyrifos (CPF) and metals such as copper can impair swimming behavior in fish. However, the impact to swimming behavior from exposure to mixtures of neurotoxicants has received little attention. In the current study, we analyzed spontaneous swimming rates of adult zebrafish (Danio rerio) to investigate in vivo mixture interactions involving two chemical classes. Zebrafish were exposed to the neurotoxicants copper chloride (CuCl, 0.1 μM, 0.25 μM, 0.6 μM, or 6.3, 16, 40 p...

  1. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida

    Energy Technology Data Exchange (ETDEWEB)

    Jager, Tjalling [Department of Theoretical Biology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands)]. E-mail: tjalling@bio.vu.nl; Crommentuijn, Trudie [Ministry of Spatial Planning, Housing and the Environment (VROM), Rijnstraat 8, P.O. Box 30945, 2500 GX, The Hague (Netherlands); Gestel, Cornelis A.M. van [Department of Animal Ecology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands); Kooijman, Sebastiaan A.L.M. [Department of Theoretical Biology, Vrije Universiteit, de Boelelaan 1085, NL-1081 HV, Amsterdam (Netherlands)

    2007-01-15

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level. - Exposure to chlorpyrifos in food affects reproduction in springtails according to two distinct toxic mechanisms.

  2. Chlorpyrifos causes decreased organic matter decomposition by suppressing earthworm and termite communities in tropical soil

    Energy Technology Data Exchange (ETDEWEB)

    De Silva, P. Mangala C.S., E-mail: msilva@falw.vu.n [Department of Animal Ecology, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Department of Zoology, Faculty of Science, University of Ruhuna, Matara (Sri Lanka); Pathiratne, Asoka [Department of Zoology, Faculty of Science, University of Kelaniya, Kelaniya (Sri Lanka); Straalen, Nico M. van; Gestel, Cornelis A.M. van [Department of Animal Ecology, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2010-10-15

    Effects of pesticides on structural and functional properties of ecosystems are rarely studied under tropical conditions. In this study litterbag and earthworm field tests were performed simultaneously at the same tropical field site sprayed with chlorpyrifos (CPF). The recommended dose of CPF (0.6 kg a.i. ha{sup -1}) and two higher doses (4.4-8.8 kg a.i. ha{sup -1}) significantly decreased litter decomposition during the first 3 months after application, which could be explained from lower earthworm and termite abundances during this period. Species-specific effects of CPF on organism abundance and biomass were observed, with termites being mostly affected followed by the earthworm Perionyx excavatus; the earthworm Megascolex sp. was least affected. Recovery was completed within 6 months. Decomposition in the controls and lowest two treatments was completed within 4 months, which suggests the need for modification of standard test guidelines to comply with faster litter degradation under tropical conditions. - Effects of chlorpyrifos on functional and structural endpoints in soil.

  3. Chlorpyrifos Determined in Human Blood by UPLC-MS/MS and Its Application in Poisoning Cases

    Institute of Scientific and Technical Information of China (English)

    QIAO Zheng; YAN Hui; ZHUO Xian-yi; SHEN Bao-hua

    2015-01-01

    Objective To determine the chlorpyrifos in human blood by liquid chromatography-tandemmass spectrometry and to validate its application in poisoning cases. Methods The samples were extracted by a simple one-step protein precipitation procedure. Chromatography was performed on a Capcell Pack C18 mG II column (250 mm×2.0 mm, 5μm) using an isocratic elution of solvent A (0.1% formic acid-water with 2 mmol/L ammoniumacetate) and solvent B (methanol with 2 mmol/L ammoniumacetate) at 5∶95 (V∶V).Results The linearranged from5 to 500ng/mL (r=0.9987).Thelimitofdetection (LOD) and the lower limit of quantification (LLOQ ) were 2 ng/mL and 4 ng/mL , respectively. For this method, the precision and accuracy of intra-day and inter-day were <10% and 97.44%-101.10%, respectively. The re-sults in stability test of long-termfrozen were satisfied. The matrix effect, recovery and process efficien-cy were 64.97%-86.81%, 76.70%-85.52%, and 55.57%-66.58%, respectively. Conclusion This method can provide a rapid approach to chlorpyrifos extraction and determination in toxicological analysis of forensic and clinical treatment.

  4. Developmental neurotoxic effects of two pesticides: Behavior and biomolecular studies on chlorpyrifos and carbaryl.

    Science.gov (United States)

    Lee, Iwa; Eriksson, Per; Fredriksson, Anders; Buratovic, Sonja; Viberg, Henrik

    2015-11-01

    In recent times, an increased occurrence of neurodevelopmental disorders, such as neurodevelopmental delays and cognitive abnormalities has been recognized. Exposure to pesticides has been suspected to be a possible cause of these disorders, as these compounds target the nervous system of pests. Due to the similarities of brain development and composition, these pesticides may also be neurotoxic to humans. We studied two different pesticides, chlorpyrifos and carbaryl, which specifically inhibit acetylcholinesterase (AChE) in the nervous system. The aim of the study was to investigate if the pesticides can induce neurotoxic effects, when exposure occurs during a period of rapid brain growth and maturation. The results from the present study show that both compounds can affect protein levels in the developing brain and induce persistent adult behavior and cognitive impairments, in mice neonatally exposed to a single oral dose of chlorpyrifos (0.1, 1.0 or 5mg/kg body weight) or carbaryl (0.5, 5.0 or 20.0mg/kg body weight) on postnatal day 10. The results also indicate that the developmental neurotoxic effects induced are not related to the classical mechanism of acute cholinergic hyperstimulation, as the AChE inhibition level (8-12%) remained below the threshold for causing systemic toxicity. The neurotoxic effects are more likely caused by a disturbed neurodevelopment, as similar behavioral neurotoxic effects have been reported in studies with pesticides such as organochlorines, organophosphates, pyrethroids and POPs, when exposed during a critical window of neonatal brain development.

  5. Opuntia ficus indica extract protects against chlorpyrifos-induced damage on mice liver.

    Science.gov (United States)

    Ncibi, Saida; Ben Othman, Mahmoud; Akacha, Amira; Krifi, Mohamed Naceur; Zourgui, Lazhar

    2008-02-01

    This original study investigates the role of Opuntia ficus indica (cactus) cladodes extract against liver damage induced in male SWISS mice by an organophosphorous insecticide, the chlorpyrifos (CPF). Liver damage was evaluated by the measure of its weight and the quantification of some biochemical parameters, such as alanine amino transferase (ALAT), aspartate amino transferase (ASAT), phosphatase alkaline (PAL), lactate dehydrogenase (LDH), cholesterol and albumin in serum by spectrophotometric techniques. The experimental approach lasted 48 h and consisted of 6 treatments of six mice each one; (1) control, (2) 10 mg/kg (b.w) CPF, (3) 10mg/kg (b.w) CPF with 100 mg/kg (b.w) cactus, (4) 150 mg/kg (b.w)CPF, (5) 150 mg/kg (b.w) CPF with 1.5 g/kg cactus, (6) 1.5 g/kg cactus. Both chlorpyrifos and cactus were administrated orally via gavages. Our results showed that CPF affects significantly all parameters studied. However, when this pesticide was administrated associated to cactus, we noticed a recovery of all their levels. In the other hand, cactus alone did not affect the studied parameters. These results allow us to conclude firstly that CPF is hepatotoxic and secondly that Opuntia ficus indica stem extract protects the liver and decreases the toxicity induced by this organophosphorous pesticide.

  6. Peak centiles of chlorpyrifos surface-water concentrations in the NAWQA and NASQAN programs.

    Science.gov (United States)

    Mosquin, Paul L; Aldworth, Jeremy; Poletika, Nicholas N

    2015-02-01

    We provide upper bound estimates for peak centiles of surface water chlorpyrifos concentration readings within spatial, temporal, and land-use domains of the United States Geological Survey (USGS) National Water-Quality Assessment (NAWQA) and National Stream Quality Accounting Network (NASQAN) programs. These datasets have large overall sample sizes but variable sampling frequencies and, for chlorpyrifos, extremely high levels of non-detections. Point and interval estimates are provided for the 90th, 95th, 99th, and the 99.9th centiles, given sufficient sample size. Overall upper bound estimates for the NAWQA program over the period 1992-2011 for the 90th, 95th, 99th, and 99.9th centiles are approach, finding centiles of pooled data across aggregates of site-years. Although the population quantity estimated by a pooled data centile is not the easily interpretable average of population site-year centiles, we provide strong support that it bounds this average by a combination of theory, comparison of NAWQA aggregate and direct estimates, and using modeled populations. PMID:25497425

  7. Pilot biomonitoring of adults and children following use of chlorpyrifos shampoo and flea collars on dogs.

    Science.gov (United States)

    Dyk, Melinda Bigelow; Chen, Zhenshan; Mosadeghi, Sasan; Vega, Helen; Krieger, Robert

    2011-01-01

    Pesticide handlers and pet owners who use products such as shampoos and dips and insecticide-impregnated collars to treat and control fleas on companion animals are exposed to a variety of active ingredients. Chlorpyrifos exposures of adults and children were measured using urine biomonitoring following use of over-the-counter products on dogs. Age and gender-specific measurements of urinary 3, 5, 6-trichloro-2-pyridinol (TCPy) revealed modest elevations of biomarker excretion following shampoo/dips. Smaller TCPy increments were measured following application of impregnated dog collars. The extent of indoor activity and potential pet contact were important determinants of urine biomarker level. Children without direct pet contact excreted more TCPy following collar application. Pet collars may be a source of indoor surface contamination and human exposure. Children excreted up to 4 times more TCPy than adults when urine volumes were adjusted using age-specific creatinine excretion levels. Although chlorpyrifos is no longer used in the United States in pet care products, results of this research provide perspective on the extent of human exposure from similar pet care products. These pilot studies demonstrated that pet care products such as insecticidal shampoos and dips and impregnated collars may expose family members to low levels of insecticide relative to toxic levels of concern.

  8. Pilot biomonitoring of adults and children following use of chlorpyrifos shampoo and flea collars on dogs.

    Science.gov (United States)

    Dyk, Melinda Bigelow; Chen, Zhenshan; Mosadeghi, Sasan; Vega, Helen; Krieger, Robert

    2011-01-01

    Pesticide handlers and pet owners who use products such as shampoos and dips and insecticide-impregnated collars to treat and control fleas on companion animals are exposed to a variety of active ingredients. Chlorpyrifos exposures of adults and children were measured using urine biomonitoring following use of over-the-counter products on dogs. Age and gender-specific measurements of urinary 3, 5, 6-trichloro-2-pyridinol (TCPy) revealed modest elevations of biomarker excretion following shampoo/dips. Smaller TCPy increments were measured following application of impregnated dog collars. The extent of indoor activity and potential pet contact were important determinants of urine biomarker level. Children without direct pet contact excreted more TCPy following collar application. Pet collars may be a source of indoor surface contamination and human exposure. Children excreted up to 4 times more TCPy than adults when urine volumes were adjusted using age-specific creatinine excretion levels. Although chlorpyrifos is no longer used in the United States in pet care products, results of this research provide perspective on the extent of human exposure from similar pet care products. These pilot studies demonstrated that pet care products such as insecticidal shampoos and dips and impregnated collars may expose family members to low levels of insecticide relative to toxic levels of concern. PMID:21240711

  9. Biodegradation of chlorpyrifos and its hydrolysis product 3,5,6-trichloro-2-pyridinol by a new fungal strain Cladosporium cladosporioides Hu-01.

    Directory of Open Access Journals (Sweden)

    Shaohua Chen

    Full Text Available Intensive use of chlorpyrifos has resulted in its ubiquitous presence as a contaminant in surface streams and soils. It is thus critically essential to develop bioremediation methods to degrade and eliminate this pollutant from environments. We present here that a new fungal strain Hu-01 with high chlorpyrifos-degradation activity was isolated and identified as Cladosporium cladosporioides based on the morphology and 5.8S rDNA gene analysis. Strain Hu-01 utilized 50 mg·L(-1 of chlorpyrifos as the sole carbon of source, and tolerated high concentration of chlorpyrifos up to 500 mg·L(-1. The optimum degradation conditions were determined to be 26.8°C and pH 6.5 based on the response surface methodology (RSM. Under these conditions, strain Hu-01 completely metabolized the supplemented chlorpyrifos (50 mg·L(-1 within 5 d. During the biodegradation process, transient accumulation of 3,5,6-trichloro-2-pyridinol (TCP was observed. However, this intermediate product did not accumulate in the medium and disappeared quickly. No persistent accumulative metabolite was detected by gas chromatopraphy-mass spectrometry (GC-MS analysis at the end of experiment. Furthermore, degradation kinetics of chlorpyrifos and TCP followed the first-order model. Compared to the non-inoculated controls, the half-lives (t(1/2 of chlorpyrifos and TCP significantly reduced by 688.0 and 986.9 h with the inoculum, respectively. The isolate harbors the metabolic pathway for the complete detoxification of chlorpyrifos and its hydrolysis product TCP, thus suggesting the fungus may be a promising candidate for bioremediation of chlorpyrifos-contaminated water, soil or crop.

  10. Biodegradation of chlorpyrifos and its hydrolysis product 3,5,6-trichloro-2-pyridinol by a new fungal strain Cladosporium cladosporioides Hu-01.

    Science.gov (United States)

    Chen, Shaohua; Liu, Chenglan; Peng, Chuyan; Liu, Hongmei; Hu, Meiying; Zhong, Guohua

    2012-01-01

    Intensive use of chlorpyrifos has resulted in its ubiquitous presence as a contaminant in surface streams and soils. It is thus critically essential to develop bioremediation methods to degrade and eliminate this pollutant from environments. We present here that a new fungal strain Hu-01 with high chlorpyrifos-degradation activity was isolated and identified as Cladosporium cladosporioides based on the morphology and 5.8S rDNA gene analysis. Strain Hu-01 utilized 50 mg·L(-1) of chlorpyrifos as the sole carbon of source, and tolerated high concentration of chlorpyrifos up to 500 mg·L(-1). The optimum degradation conditions were determined to be 26.8°C and pH 6.5 based on the response surface methodology (RSM). Under these conditions, strain Hu-01 completely metabolized the supplemented chlorpyrifos (50 mg·L(-1)) within 5 d. During the biodegradation process, transient accumulation of 3,5,6-trichloro-2-pyridinol (TCP) was observed. However, this intermediate product did not accumulate in the medium and disappeared quickly. No persistent accumulative metabolite was detected by gas chromatopraphy-mass spectrometry (GC-MS) analysis at the end of experiment. Furthermore, degradation kinetics of chlorpyrifos and TCP followed the first-order model. Compared to the non-inoculated controls, the half-lives (t(1/2)) of chlorpyrifos and TCP significantly reduced by 688.0 and 986.9 h with the inoculum, respectively. The isolate harbors the metabolic pathway for the complete detoxification of chlorpyrifos and its hydrolysis product TCP, thus suggesting the fungus may be a promising candidate for bioremediation of chlorpyrifos-contaminated water, soil or crop.

  11. Dietary predictors of young children’s exposures to chlorpyrifos, permethrin, and 2,4-D using urinary biomonitoring

    Science.gov (United States)

    Few data exist on the association between dietary habits and urinary biomarker concentrations of pesticides in children. The objective was to examined the association between the weekly intake frequency of 65 food items and urinary biomarkers of exposure to chlorpyrifos (3,5,6-tr...

  12. Effectiveness of personal protective equipment: Relevance of dermal and inhalation exposure to chlorpyrifos among pest control operators

    NARCIS (Netherlands)

    Jagt, K. van der; Tielemans, E.; Links, I.; Brouwer, D.; Hemmen, J. van

    2004-01-01

    This study assessed the effectiveness of a custom fit personal protective equipment (PPE) program aimed at reducing occupational exposure to pesticides. The intervention study was carried out on 15 pest control operators (PCOs) during mixing/loading and application of chlorpyrifos. Each worker was m

  13. Pharmacokinetics and effects on serum cholinesterase activities of organophosphorus pesticides acephate and chlorpyrifos in chimeric mice transplanted with human hepatocytes.

    Science.gov (United States)

    Suemizu, Hiroshi; Sota, Shigeto; Kuronuma, Miyuki; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-11-01

    Organophosphorus pesticides acephate and chlorpyrifos in foods have potential to impact human health. The aim of the current study was to investigate the pharmacokinetics of acephate and chlorpyrifos orally administered at lowest-observed-adverse-effect-level doses in chimeric mice transplanted with human hepatocytes. Absorbed acephate and its metabolite methamidophos were detected in serum from wild type mice and chimeric mice orally administered 150mg/kg. Approximately 70% inhibition of cholinesterase was evident in plasma of chimeric mice with humanized liver (which have higher serum cholinesterase activities than wild type mice) 1day after oral administrations of acephate. Adjusted animal biomonitoring equivalents from chimeric mice studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and in vitro metabolic clearance data with a simple physiologically based pharmacokinetic (PBPK) model. Estimated plasma concentrations of acephate and chlorpyrifos in humans were consistent with reported concentrations. Acephate cleared similarly in humans and chimeric mice but accidental/incidental overdose levels of chlorpyrifos cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in mice. The data presented here illustrate how chimeric mice transplanted with human hepatocytes in combination with a simple PBPK model can assist evaluations of toxicological potential of organophosphorus pesticides.

  14. The expression of proteins involved in digestion and detoxification are regulated in Helicoverpa armigera to cope up with chlorpyrifos insecticide.

    Science.gov (United States)

    Dawkar, Vishal V; Chikate, Yojana R; More, Tushar H; Gupta, Vidya S; Giri, Ashok P

    2016-02-01

    Helicoverpa armigera is a key pest in many vital crops, which is mainly controlled by chemical strategies. To manage this pest is becoming challenging due to its ability and evolution of resistance against insecticides. Further, its subsequent spread on nonhost plant is remarkable in recent times. Hence, decoding resistance mechanism against phytochemicals and synthetic insecticides is a major challenge. The present work describes that the digestion, defense and immunity related enzymes are associated with chlorpyrifos resistance in H. armigera. Proteomic analysis of H. armigera gut tissue upon feeding on chlorpyrifos containing diet (CH) and artificial diet (AD) using nano-liquid chromatography-mass spectrometry identified upregulated 23-proteins in CH fed larvae. Database searches combined with gene ontology analysis revealed that the identified gut proteins engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification. Biochemical and quantitative real-time polymerase chain reaction analysis of candidate proteins indicated that insects were struggling to get nutrients and energy in presence of CH, while at the same time endeavoring to metabolize chlorpyrifos. Moreover, we proposed a potential processing pathway of chlorpyrifos in H. armigera gut by examining the metabolites using gas chromatography-mass spectrometry. H. armigera exhibit a range of intriguing behavioral, morphological adaptations and resistance to insecticides by regulating expression of proteins involved in digestion and detoxification mechanisms to cope up with chlorpyrifos. In these contexts, as gut is a rich repository of biological information; profound analysis of gut tissues can give clues of detoxification and resistance mechanism in insects. PMID:25284010

  15. Effects of Sequential Applications of Bassa 50EC (Fenobucarb) and Vitashield 40EC (Chlorpyrifos ethyl) on Acetylcholinesterase Activity in Climbing Perch (Anabas testudineus) Cultured in Rice Fields in the Mekong Delta, Vietnam.

    Science.gov (United States)

    Tam, Nguyen Thanh; Berg, Håkan; Laureus, Jenny; Cong, Nguyen Van; Tedengren, Michael

    2016-07-01

    This study assesses the effects of sequential applications of the insecticides Bassa 50EC (fenobucarb-F) and Vitashield 40EC (chlorpyrifos ethyl-CPF), sprayed at concentrations used by rice farmers in the Mekong Delta, on the brain acetylcholinesterase (AChE) in climbing perch fingerlings. After spraying the pesticides on the rice fields, the water concentrations of both insecticides decreased below the detection levels within 3 days. The sequential applications caused significant inhibition on the brain AChE activity in the exposed fish. The inhibition by F was quicker, but less prolonged, than for CPF. The inhibition levels caused by the sequential applications were lower than those caused by only CPF and by a mixture of CPF and F. The results indicate that sequential applications of pesticides could have a negative impact on aquatic organisms and fish yields, with implication for the aquatic biodiversity, local people's livelihood and the aquaculture industry in the Mekong Delta. PMID:27075585

  16. Vitamin E Mitigates Chronic Chlorpyrifos-Induced Oxidative Changes in Pituitary Glands and Testes in Wistar Rats

    Directory of Open Access Journals (Sweden)

    M. Shittu

    2012-01-01

    Full Text Available Problem statement: The sperm counts of men have declined by about 50% in the last few decades. The contribution of environmental contaminants to this decline cannot be overemphasized. Pesticide is one of the most pervasive environmental chemical contaminants that have been of increased use due to the compelling need to feed the ever-growing world human and animal population and protect their health. Chlorpyrifos (CPF, a widely used Organophosphate (OP insecticide has been reported to alter male reproductive hormones and semen characteristics. Apart from acetyl cholinesterase inhibition, the induction of oxidative stress is one of the molecular mechanisms implicated in CPF poisoning. Approach: The present study was aimed at evaluating the effect of vitamin E in mitigating oxidative damage to the pituitary gland and the testis, induced by chronic CPF administration in Wistar rats. Methodology: Twenty adult male Wistar rats divided into 4 groups of 5 rats in each group were used for this study. Group I received soya oil (2 mL kg-1, while Group II was administered vitamin E (75 mg kg-1; Group III was administered CPF only (10.6 mg kg-1~1/8th LD50, while group IV was pretreated with vitamin E (75 mg kg-1 and exposed to CPF (10.6 mg kg-1 30 min later. The regimens were administered orally by gavages once daily for a period of 15 weeks. At the end of the treatment period, the rats were sacrificed and the pituitary glands and testicular tissues were assayed for the concentrations of Malonaldehyde (MDA and the activities of Superoxide Dismutase (SOD and Catalane (CAT. Results: The result showed that the increase in concentrations of pituitary and testicular MDA and a decrease in the activities of SOD and CAT recorded in the group exposed to CPF were ameliorated by pretreatment with vitamin E. Conclusion: This indicates that vitamin E mitigates reproductive toxicity induced by chronic CPF exposure due to its protective antioxidant activity on pituitary

  17. Biodegradation characteristics of chlorpyrifos by sodium alginate immobilized bacteria%海藻酸钠固定化细菌对毒死蜱的降解特性

    Institute of Scientific and Technical Information of China (English)

    段海明

    2012-01-01

    Chlorpyrifos [(O,O-diethyl-O-3,5,6-trichloro-2-pyridinyl) phosphorothioate] is a broad spectrum of moderately toxic organophosphorus pesticide used as insecticide on a large variety of crops including fruits, vegetables, cotton, corn and wheat. With especially the recent elimination of five highly toxic organophosphorus pesticides, chlorpyrifos has been widely used in China. Consequently, large quantities of wastewater containing chlorpyrifos have been generated from pesticide industry and lot more chlorpyrifos scattered in the depths of soils and waters in the fields. Moreover, various reports have noted that chlorpyrifos have had visible toxicity in mammalians. Therefore the high degree of persistence of chlorpyrifos in the environment and the toxic effects on humans had necessitated removal. Biodegradation has received increasing attention as an efficient and cheap biotechnological approach to cleaning up polluted environments. Several chemicals have been successfully removed from soil and aquatic environments using degrading microbes. Similarly, biodegradation has been the major mechanism for removing chlorpyrifos residues, especially for treatments of discharged wastewater from the processes of chlorpyrifos production. Previous successes in isolating Bacillus cereus strain from chlorpyrifos degradation have augmented scarce literatures on this strain of chlorpyrifos biodegradation. In order to enhance degradation efficiency, B. cereus HY-1 strain was immobilized with sodium alginate using the syringe titration method. Also biodegradation characteristics of chlorpyrifos by immobilized B. cereus strain were further investigated. While the optimal reaction time was obtained, the effects of the various parameters (e.g., amounts of immobilized biomass, pH and chlorpyrifos initial concentration) of biodegradation were studied. The results showed that chlorpyrifos were readily degraded by sodium alginateimmobilized B.cereus. The appropriate concentration of sodium

  18. Chronic exposure to chlorpyrifos reveals two modes of action in the springtail Folsomia candida.

    Science.gov (United States)

    Jager, Tjalling; Crommentuijn, Trudie; van Gestel, Cornelis A M; Kooijman, Sebastiaan A L M

    2007-01-01

    Organophosphates are popular insecticides, but relatively little is known about their chronic effects on ecologically relevant endpoints. In this paper, we examine a life-cycle experiment with the springtail Folsomia candida, exposed via food to chlorpyrifos (CPF). The results for all endpoints (survival, growth and reproduction) were analyzed using the DEBtox model. Growth was unaffected by CPF, even at concentrations causing severe effects on survival and reproduction. Model analysis suggests that CPF directly affects the process of egg production. For the short-term response (45 days), this single mode of action accurately agreed with the data. However, the full data set (120 days) revealed a dose-related decrease in reproduction at low concentrations after prolonged exposure, not covered by the same mechanism. It appears that CPF interacts with senescence by increasing oxidative damage. This assumption fits the data well, but has little consequences for the predicted response at the population level. PMID:16762466

  19. Individual and combined toxic effects of cypermethrin and chlorpyrifos on earthworm

    Institute of Scientific and Technical Information of China (English)

    Shiping Zhou; Changqun Duan; Wong Hang Gi Michelle; Fazhong Yang; Xuehua Wang

    2011-01-01

    Toxicities were assessed for a pyrethroid (cypermethrin) and an organophosphate insecticide (chlorpyrifos) individually and in combination. A series of tests were conducted on different responses (acute, chronic, behavioral) of earthworms of species Eisenia fetida andrei in the ecological risk assessment of these pesticides. The results showed that the toxicity of the mixture of cypermethrin and chiorpyfifos was significantly higher than either of these pesticides individually, especially on the earthworm's chronic responses.At a concentration of 5 mg/kg, the mixture caused significant reductions on the growth and reproduction rates of earthworms, but did not cause any significant effect when the individual was tested. The increase in toxicity of the pesticide mixture means that the use of toxicity data obtained exclusively from single-pesticide experiments may underestimate the ecological risk of pesticides that actually present in the field.

  20. Chlorpyrifos induced testicular damage in rats: ameliorative effect of glutathione antioxidant.

    Science.gov (United States)

    Elsharkawy, Eman E; Yahia, Doha; El-Nisr, Neveen A

    2014-09-01

    This study investigated the induction of oxidative stress in the testes of adult rats exposed to chlorpyrifos (CPF). CPF was administered orally, in a dose of 30 mg/kg body weight to male rats for 90 days, twice weekly. Coadministration of water-soluble nonenzymatic antioxidant glutathione (GSH) was performed in a dose of 100 mg/kg body weight, orally, for the same period. Another two groups of male rats were administered GSH and corn oil, respectively. The activities of superoxide dismutase and GSH reductase were decreased while the levels of lipid peroxidation were increased in the testicular tissues of the exposed animals. Testosterone level in the serum was significantly decreased. A decrease in the histochemical determination of testicular alkaline phosphatase was observed in CPF-treated rats. A significant decrease in all stages of spermatogenesis in the seminiferous tubules was recorded in the exposed animals. Coadministration of GSH restored these parameters. PMID:23172834

  1. Efficacy of Aspergillus sp. for degradation of chlorpyrifos in batch and continuous aerated packed bed bioreactors.

    Science.gov (United States)

    Yadav, Maya; Srivastva, Navnita; Shukla, Awadhesh Kumar; Singh, Ram Sharan; Upadhyay, Siddh Nath; Dubey, Suresh Kumar

    2015-01-01

    Aerobic biodegradation of chlorpyrifos (CP) by Aspergillus sp. was investigated in batch and continuous packed bed bioreactors. The optimal process parameters for achieving the maximum removal efficiency (RE), determined using a batch bioreactor packed with polyurethane foam pieces, were inoculum level: 2.5 mg (wet weight) mL(-1), pH 7.0, temperature 28 °C, DO 5.8 mg L(-1), and CP concentration 300 mg L(-1). The continuous packed bed bioreactor was operated at flow rates ranging from 10 to 40 mL h(-1) while keeping other parameters at their optimal level. Steady-state CP removal efficiencies greater than 85 % were obtained up to the inlet loading of 180 mg L(-1) d(-1). The continuous bioreactor behaved as a plug flow unit and was able to stabilize quickly after perturbation in the inlet loading.

  2. Hormetic response of cholinesterase from Daphnia magna in chronic exposure to triazophos and chlorpyrifos

    Institute of Scientific and Technical Information of China (English)

    Shaonan Li; Yajun Tan

    2011-01-01

    In vivo activity of cholinesterase (ChE) in Daphnia magna was measured at different time points during 21-day exposure to triazophos and chlorpyrifos ranging from 0.05 to 2.50 μg/L and 0.01 to 2.00 μg/L, respectively.For exposure to triazophos, ChE was induced up to 176.5% at 1.5 μg/L and day 10 when measured by acetylthiocholine (ATCh), whereas it was induced up to 174.2% at 0.5 μg/L and day 10 when measured by butyrylthiocholine (BTCh).For exposure to chlorpyrifos, ChE was induced up to 134.0% and 160.5% when measured by ATCh and BTCh, respectivly, with both maximal inductions detected at 0.l μg/L and day 8.Obvious induction in terms of ChE activity was also detected in daphnia removed from exposures 24 hr after their birth and kept in a recovery culture for 21 days.Results indicated that the enzyme displayed symptoms of hormesis, a characteristic featured by conversion from low-dose stimulation to high-dose inhibition.In spite of that, no promotion in terms of reproduction rate and body size was detected at any tested concentrations regardless of whether the daphnia were collected at end of the 21-day exposure or at end of a 21-day recovery culture.This suggested that induction of ChE caused by anticholinesterases had nothing to do with the prosperity of the daphnia population.

  3. Hormetic response of cholinesterase from Daphnia magna in chronic exposure to triazophos and chlorpyrifos.

    Science.gov (United States)

    Li, Shaonan; Tan, Yajun

    2011-01-01

    In vivo activity of cholinesterase (ChE) in Daphnia magna was measured at different time points during 21-day exposure to triazophos and chlorpyrifos ranging from 0.05 to 2.50 microg/L and 0.01 to 2.00 microg/L, respectively. For exposure to triazophos, ChE was induced up to 176.5% at 1.5 microg/L and day 10 when measured by acetylthiocholine (ATCh), whereas it was induced up to 174.2% at 0.5 microg/L and day 10 when measured by butyrylthiocholine (BTCh). For exposure to chlorpyrifos, ChE was induced up to 134.0% and 160.5% when measured by ATCh and BTCh, respectively, with both maximal inductions detected at 0.1 microg/L and day 8. Obvious induction in terms of ChE activity was also detected in daphnia removed from exposures 24 hr after their birth and kept in a recovery culture for 21 days. Results indicated that the enzyme displayed symptoms of hormesis, a characteristic featured by conversion from low-dose stimulation to high-dose inhibition. In spite of that, no promotion in terms of reproduction rate and body size was detected at any tested concentrations regardless of whether the daphnia were collected at end of the 21-day exposure or at end of a 21-day recovery culture. This suggested that induction of ChE caused by anticholinesterases had nothing to do with the prosperity of the daphnia population. PMID:21790060

  4. Impact of Location, Cropping History, Tillage, and Chlorpyrifos on Soil Arthropods in Peanut.

    Science.gov (United States)

    Cardoza, Yasmin J; Drake, Wendy L; Jordan, David L; Schroeder-Moreno, Michelle S; Arellano, Consuelo; Brandenburg, Rick L

    2015-08-01

    Demand for agricultural production systems that are both economically viable and environmentally conscious continues to increase. In recent years, reduced tillage systems, and grass and pasture rotations have been investigated to help maintain or improve soil quality, increase crop yield, and decrease labor requirements for production. However, documentation of the effects of reduced tillage, fescue rotation systems as well as other management practices, including pesticides, on pest damage and soil arthropod activity in peanut production for the Mid-Atlantic US region is still limited. Therefore, this project was implemented to assess impacts of fescue-based rotation systems on pests and other soil organisms when compared with cash crop rotation systems over four locations in eastern North Carolina. In addition, the effects of tillage (strip vs. conventional) and soil chlorpyrifos application on pod damage and soil-dwelling organisms were also evaluated. Soil arthropod populations were assessed by deploying pitfall traps containing 50% ethanol in each of the sampled plots. Results from the present study provide evidence that location significantly impacts pest damage and soil arthropod diversity in peanut fields. Cropping history also influenced arthropod diversity, with higher diversity in fescue compared with cash crop fields. Corn rootworm damage to pods was higher at one of our locations (Rocky Mount) compared with all others. Cropping history (fescue vs. cash crop) did not have an effect on rootworm damage, but increased numbers of hymenopterans, acarina, heteropterans, and collembolans in fescue compared with cash crop fields. Interestingly, there was an overall tendency for higher number of soil arthropods in traps placed in chlorpyrifos-treated plots compared with nontreated controls. PMID:26314040

  5. Integrating ecosystem services into risk management decisions: case study with Spanish citrus and the insecticide chlorpyrifos.

    Science.gov (United States)

    Deacon, Samantha; Norman, Steve; Nicolette, Joseph; Reub, Gregory; Greene, Gretchen; Osborn, Rachel; Andrews, Paul

    2015-02-01

    The European regulatory system for the approval of pesticides includes a thorough evaluation of risks to the environment and is designed to be protective of ecosystems. However, a decision to ban an agrochemical could also potentially have a negative impact on the value of ecosystem services, if resulting changes in crop management are damaging to ecosystems or result in negative socio-economic impacts. To support regulatory decision-making, consideration of ecosystem services to identify best environmental management options could be a way forward. There is generally a growing trend for the consideration of ecosystem services in decision making. Ecosystems provide the conditions for growing food, regulate water and provide wildlife habitats; these, amongst others, are known as ecosystem services. The objectives of this case study were to bring a holistic approach to decision making by valuing the environmental, social and economic benefits derived from the use of chlorpyrifos in Valencian citrus production. Spanish growers harvest between 5 and 6 milliont of citrus annually, worth an estimated €5 to 7 billion in food markets throughout Europe. The approach highlighted the potential for unintended negative consequences of regulatory decisions if the full context is not considered. In this study, rather than a regulatory restriction, the best option was the continued use of chlorpyrifos together with vegetated conservation patches as refuges for non-target insects. The conservation patches offset potential insecticidal impacts to insects whilst maintaining citrus production, farm income and the amenity value of the citrus landscape of Valencia. This was an initial proof-of-concept study and illustrates the importance of a wider perspective; other cases may have different outcomes depending on policies, the pesticide, crop scenarios, farm economics and the region.

  6. Individual variability in esterase activity and CYP1A levels in Chinook salmon (Oncorhynchus tshawytscha) exposed to esfenvalerate and chlorpyrifos

    Science.gov (United States)

    Wheelock, C.E.; Eder, K.J.; Werner, I.; Huang, H.; Jones, P.D.; Brammell, B.F.; Elskus, A.A.; Hammock, B.D.

    2005-01-01

    Acetylcholinesterase (AChE) activity has traditionally been monitored as a biomarker of organophosphate (OP) and/or carbamate exposure. However, AChE activity may not be the most sensitive endpoint for these agrochemicals, because OPs can cause adverse physiological effects at concentrations that do not affect AChE activity. Carboxylesterases are a related family of enzymes that have higher affinity than AChE for some OPs and carbamates and may be more sensitive indicators of environmental exposure to these pesticides. In this study, carboxylesterase and AChE activity, cytochrome P4501A (CYP1A) protein levels, and mortality were measured in individual juvenile Chinook salmon (Oncorhynchus tshawytscha) following exposure to an OP (chlorpyrifos) and a pyrethroid (esfenvalerate). As expected, high doses of chlorpyrifos and esfenvalerate were acutely toxic, with nominal concentrations (100 and 1 ??g/l, respectively) causing 100% mortality within 96 h. Exposure to chlorpyrifos at a high dose (7.3 ??g/l), but not a low dose (1.2 ??g/l), significantly inhibited AChE activity in both brain and muscle tissue (85% and 92% inhibition, respectively), while esfenvalerate exposure had no effect. In contrast, liver carboxylesterase activity was significantly inhibited at both the low and high chlorpyrifos dose exposure (56% and 79% inhibition, respectively), while esfenvalerate exposure still had little effect. The inhibition of carboxylesterase activity at levels of chlorpyrifos that did not affect AChE activity suggests that some salmon carboxylesterase isozymes may be more sensitive than AChE to inhibition by OPs. CYP1A protein levels were ???30% suppressed by chlorpyrifos exposure at the high dose, but esfenvalerate had no effect. Three teleost species, Chinook salmon, medaka (Oryzias latipes) and Sacramento splittail (Pogonichthys macrolepidotus), were examined for their ability to hydrolyze a series of pyrethroid surrogate substrates and in all cases hydrolysis activity was

  7. Efeito da interação do nicosulfuron e chlorpyrifos sobre o banco de sementes e os atributos microbianos do solo Effect of sequential nicosulfuron and chlorpyrifos application on seed bank and soil microbial characteristics

    Directory of Open Access Journals (Sweden)

    Taciane Almeida de Oliveira

    2009-06-01

    Full Text Available Considerando o período de competição de plantas daninhas e a incidência da lagarta-do-cartucho na cultura do milho, há necessidade de aplicação, em curto intervalo de tempo, de herbicidas e de inseticidas, principalmente o nicosulfuron e o chlorpyrifos. O objetivo deste estudo foi avaliar o efeito da aplicação sequencial do nicosulfuron e do chlorpyrifos sobre a emergência de plântulas do banco de sementes, a taxa de desprendimento de CO2 (respiração basal e o C da biomassa microbiana (CBM do solo. Foi realizada aplicação sequencial, em solo, do nicosulfuron (doses de 0 a 64 g ha-1 associado ou não ao chlorpyrifos (0 e 240 g ha-1. Aos 20, 40 e 60 dias após a aplicação (DAA dos produtos, todas as plântulas emergidas do banco de sementes foram identificadas em nível de espécie, sendo estimadas a frequência, densidade e abundância, além do índice de valor de importância (IVI. Aos 60 DAA, determinou-se também a taxa de desprendimento de CO2, o CBM e o quociente metabólico (qCO2, por meio da relação entre o CO2 acumulado e o CBM total do solo. A aplicação alterou severamente a massa de plântulas secas e o número de espécies nas doses superiores a 20 g ha-1 do nicosulfuron. Na presença do herbicida, as espécies com maior IVI foram Boehavia diffusa e Commelina benghalensis. Quanto aos bioindicadores do solo, foi observado decréscimo na taxa da respiração basal do solo com o aumento da dose aplicada do nicosulfuron associado ao chlorpyrifos, sem efeito na ausência do inseticida. Houve decréscimo linear no CBM em todos os casos, independentemente da aplicação do chlorpyrifos; entretanto, observou-se uma taxa de decréscimo 4,5 vezes maior para o solo que recebeu esse inseticida em conjunto com o nicosulfuron. A avaliação do qCO2 confirmou o efeito negativo da aplicação do inseticida e do herbicida. Conclui-se que a aplicação de chlorpyrifos + nicosulfuron promove impacto negativo sobre o banco de

  8. Avoidance behaviour of Eisenia fetida to carbofuran, chlorpyrifos, mancozeb and metamidophos in natural soils from the highlands of Colombia.

    Science.gov (United States)

    García-Santos, Glenda; Keller-Forrer, Karin

    2011-07-01

    Earthworm avoidance behaviour test is an important screening tool in soil eco-toxicology. This test has been developed and validated under North American and European conditions. However, little research has been performed on the avoidance test in the tropics. This work demonstrates the potential suitability of the avoidance behaviour test as screening method in the highlands of Colombia using Eisenia fetida as the bio-indicator species on contaminated soils with carbofuran and chlorpyrifos. Though for the two active ingredients 100% avoidance was not reached, a curve with six meaningful concentrations is provided. No significant avoidance behaviour trend was found for mancozeb and methamidophos. Tests were conducted in the field yielded similar results to the tests carried out in the laboratory for chlorpyrifos and mancozeb. However, for the case of carbofuran and methamidophos, differences of more than double in avoidance were obtained. Divergence might be explained by soil and temperature conditions.

  9. The expression profile of detoxifying enzyme of tomato leaf miner, Tuta absoluta Meyrik (Lepidoptera: Gelechiidae) to chlorpyrifos

    OpenAIRE

    Idin Zibaee; Ali Reza Bandani; Ghodratollah Sabahi

    2016-01-01

    The tomato leafminer, Tuta absoluta (Meyrich) (Lepidoptera: Gelechiidae) is an important pest of tomato crops worldwide. The persistent use of organophosphate insecticide to control this pest has led to resistance. However, there is no report on the susceptibility and resistance mechanism of field population of Tuta absoluta (Meyrik) from Iran. Furthermore, the toxicity and impact of chlorpyrifos on metabolic enzymes in this pest remains unknown. The populations of T. absoluta from Rasht in I...

  10. Synergistic effects of chlorpyrifos with piperonyl butoxide (pbo) against the lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae)

    OpenAIRE

    Akter Mst Yeasmin; Talukdar Muhammad Waliullah; ASM Shafiqur Rahman

    2014-01-01

    Objective: To investigate the co-toxicity and co-efficient activity of Chlorpyrifos (Dursban 20EC), an organophosphate and Piperonyl butoxide (PBO) against the lesser meal worm Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) (A. diaperinus). Methods: The repellent activity was carried out by the residual film assay technique. Statistically the dose mortality relationship was expressed as a median lethal dose (LD50) by the probit analysis. The regression lines and isoboles were ...

  11. COMPARATIVE EFFECTS OF PARATHION AND CHLORPYRIFOS ON EXTRACELLULAR ENDOCANNABINOID LEVELS IN RAT HIPPOCAMPUS: INFLUENCE ON CHOLINERGIC TOXICITY

    OpenAIRE

    Liu, Jing; Parsons, Loren; Pope, Carey

    2013-01-01

    Parathion (PS) and chlorpyrifos (CPF) are organophosphorus insecticides (OPs) that elicit acute toxicity by inhibiting acetylcholinesterase (AChE). Endocannabinoids (eCBs, N-arachidonoylethanolamine, AEA; 2-arachidonoylglycerol, 2AG) can modulate neurotransmission by inhibiting neurotransmitter release. We proposed that differential inhibition of eCB-degrading enzymes (fatty acid amide hydrolase, FAAH, and monoacylglycerol lipase, MAGL) by PS and CPF lead to differences in extracellular eCB l...

  12. Fitness Effects of Chlorpyrifos in the Damselfly Enallagma cyathigerum Strongly Depend upon Temperature and Food Level and Can Bridge Metamorphosis

    OpenAIRE

    Lizanne Janssens; Robby Stoks

    2013-01-01

    Interactions between pollutants and suboptimal environmental conditions can have severe consequences for the toxicity of pollutants, yet are still poorly understood. To identify patterns across environmental conditions and across fitness-related variables we exposed Enallagma cyathigerum damselfly larvae to the pesticide chlorpyrifos at two food levels or at two temperatures and quantified four fitness-related variables (larval survival, development time, mass at emergence and adult cold resi...

  13. Investigation of in vitro effects of ethephon and chlorpyrifos, either alone or in combination, on rat intestinal muscle contraction

    OpenAIRE

    Çetinkaya, Mustafa Alp; Baydan, Emine

    2010-01-01

    A range of pesticides is widely used in pest management and the chances of exposure to multiple organophosphorus (OP) compounds simultaneously are high, especially from dietary and other sources. Although health hazards of individual OP insecticides have been relatively well characterized, there is lesser information on the interactive toxicity of multiple OP insecticides. The aim of this study is to elicit the possible interactions in case combined exposure of an OP pesticide chlorpyrifos (C...

  14. Residual toxicity of abamectin, chlorpyrifos, cyromazine, indoxacarb and spinosad on Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) in greenhouse conditions

    OpenAIRE

    Ghasem Askari Saryazdi; Mir Jalil Hejazi; Moosa Saber

    2012-01-01

    Liriomyza trifolii is an important pest of vegetable crops in many parts of the world including Iran. In this study potted bean plants were sprayed with recommended field rates of abamectin, chlorpyrifos, cyromazine, indoxacarb and spinosad. To assess the residual activities of these insecticides, the plants were infested with L. trifolii adults 2 hours; 1, 3, 5, 7, 10, 15, 20, 25 and 35 days after insecticidal treatments. The adults were allowed to stay on...

  15. Chlorpyrifos Induces the Expression of the Epstein-Barr Virus Lytic Cycle Activator BZLF-1 via Reactive Oxygen Species

    OpenAIRE

    Ling Zhao; Fei Xie; Ting-ting Wang; Meng-yu Liu; Jia-la Li; Lei Shang; Zi-xuan Deng; Peng-xiang Zhao; Xue-mei Ma

    2015-01-01

    Organophosphate pesticides (OPs) are among the most widely used synthetic chemicals for the control of a wide variety of pests, and reactive oxygen species (ROS) caused by OPs may be involved in the toxicity of various pesticides. Previous studies have demonstrated that a reactivation of latent Epstein-Barr virus (EBV) could be induced by oxidative stress. In this study, we investigated whether OPs could reactivate EBV through ROS accumulation. The Raji cells were treated with chlorpyrifos (C...

  16. Alterations in Central Nervous System Serotonergic and Dopaminergic Synaptic Activity in Adulthood after Prenatal or Neonatal Chlorpyrifos Exposure

    OpenAIRE

    Aldridge, Justin E; Meyer, Armando; Seidler, Frederic J; Slotkin, Theodore A.

    2005-01-01

    Exposure to chlorpyrifos (CPF) alters neuronal development of serotonin (5HT) and dopamine systems, and we recently found long-term alterations in behaviors related to 5HT function. To characterize the synaptic mechanisms underlying these effects, we exposed developing rats to CPF regimens below the threshold for systemic toxicity, in three treatment windows: gestational days (GD) 17–20, postnatal days (PN) 1–4, or PN11–14. In early adulthood (PN60), we assessed basal neurotransmitter content...

  17. DOSE-RELATED GENE EXPRESSION CHANGES IN FOREBRAIN FOLLOWING ACUTE, LOW-LEVEL CHLORPYRIFOS EXPOSURE IN NEONATAL RATS

    OpenAIRE

    Ray, Anamika; Liu, Jing; Ayoubi, Patricia; Pope, Carey

    2010-01-01

    Chlorpyrifos (CPF) is a widely used organophosphorus insecticide (OP) and putative developmental neurotoxicant in humans. The acute toxicity of CPF is elicited by acetylcholinesterase (AChE) inhibition. We characterized dose-related (0.1, 0.5, 1 and 2 mg/kg) gene expression profiles and changes in cell signaling pathways 24 hr following acute CPF exposure in seven day-old rats. Microarray experiments indicated that approximately 9% of the 44,000 genes were differentially expressed following e...

  18. Repeated exposures to low-level chlorpyrifos results in impairments in sustained attention and increased impulsivity in rats

    OpenAIRE

    Middlemore-Risher, M.L.; Buccafusco, J.J.; Terry, A.V.

    2010-01-01

    Organophosphates such as chlorpyrifos (CPF) are among the most commonly used pesticides in the world. Therefore, it is not surprising that measurable levels of organophosphates (including CPF) are found in over 50% of fresh fruits, vegetables and grains that we consume and that approximately 80% of adults in the US have detectable levels of CPF metabolites in their urine. It is well known that acute exposure to organophosphates can cause cognitive deficits; however, the effects of daily or in...

  19. Residual Toxicity of Abamectin, Chlorpyrifos, Cyromazine, Indoxacarb and Spinosad on Liriomyza trifolii (Burgess (Diptera: Agromyzidae in Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Ghasem Askari Saryazdi

    2012-01-01

    Full Text Available Liriomyza trifolii is an important pest of vegetable crops in many parts of the worldincluding Iran. In this study potted bean plants were sprayed with recommended fieldrates of abamectin, chlorpyrifos, cyromazine, indoxacarb and spinosad. To assess the residualactivities of these insecticides, the plants were infested with L. trifolii adults 2 hours; 1, 3,5, 7, 10, 15, 20, 25 and 35 days after insecticidal treatments. The adults were allowed to stayon treated plants for eight hours. The treated plants were kept in a greenhouse. Numberof feeding stipples and larval mines on leaves, as well as pupation and adult eclosion rateswere assessed. Two-way ANOVA procedure of SAS was used for statistical analysis andthe treatment means were separated using Duncan’s multiple range test. Abamectin andspinosad severely affected egg hatching and embryonic development. Eggs oviposited inleaves with residues of chlorpyrifos up to 5 days old, had reduced hatching. Larval developmentwas also, affected by residues of chlorpyrifos up to four weeks old. Indoxacarbreduced larval development and adult eclosion in treatments with up to 20 days old residues.Cyromazine had no effect on the number of larval mines, but, pupation was severelyhampered and adult eclosion was completely ceased even in treatments with five weeksold residues. Determining the residual activity of insecticides used for controlling this pestis useful in avoiding unnecessary treatments.

  20. Evaluation of temephos and chlorpyrifos-methyl against Culex pipiens (Diptera: Culicidae) larvae in septic tanks in Antalya, Turkey.

    Science.gov (United States)

    Cetin, H; Yanikoglu, A; Kocak, O; Cilek, J E

    2006-11-01

    The larvicidal activity of chlorpyrifos-methyl and temephos was evaluated against Culex pipiens L. (Diptera: Culicidae) in septic tanks in Antalya, Turkey. Chlorpyrifos-methyl (Pyrifos MT 25 emulsifiable concentrate [EC] ) was evaluated at application rates of 0.04, 0.08, and 0.12 mg active ingredient (AI)/liter, and temephos (Temeguard 50 EC) was evaluated at 0.02, 0.04, and 0.06 mg (AI)/liter during a 21-d study. Generally, overall larval reduction in septic tanks from single- and multifamily dwellings treated with either larvicide was significantly greater than pretreatment levels and control tanks for the duration of the study. At 14 d posttreatment, duration of control was greatest in multifamily tanks treated with chlorpyrifos-methyl at the highest application rate with similar levels of control through 21 d for single-family dwellings (range 97-100%). Septic tanks from both types of family dwellings treated at the highest application rate of temephos resulted in >90% reduction through day 21 (range 91-100%). Laboratory bioassays of septic tank water treated at field application rates, without daily dilution, revealed that complete larval mortality was achieved for 21 d at each application rate and formulation. It is thought that daily addition of water and organic matter to the septic tanks in the single and multifamily dwellings influenced the duration of effectiveness of the larvicides.

  1. Autophagy regulates chlorpyrifos-induced apoptosis in SH-SY5Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hyeon [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Shin, In Chul [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2013-04-01

    Recent studies have shown that up-regulation of autophagy may be a tractable therapeutic intervention for clearing disease-causing proteins, including α-synuclein, ubiquitin, and other misfolded or aggregated proteins in pesticide-induced neurodegeneration. In a previous study, we reported that chlorpyrifos (CPF)-induced mitochondria-dependent apoptosis is mediated through reactive oxygen species in SH-SY5Y cells. In this study, we explored a novel pharmacotherapeutic approach to prevent CPF neurotoxicity involving the regulation of autophagy. We investigated the modulation of CPF-induced apoptosis according to autophagy regulation. We found that CPF induced apoptosis in SH-SY5Y cells, as demonstrated by the activation of caspase-3 and nuclear condensation. In addition, we observed that cells treated with CPF underwent autophagic cell death by monitoring the expression of LC3-II and p62. Pretreatment with the autophagy inducer rapamycin significantly enhanced the cell viability of CPF-exposed cells, and the enhancement of cell viability was partially due to alleviation of CPF-induced apoptosis via a decrease in levels of cleaved caspase-3. Specifically, rapamycin pretreatment decreased Bax and increased Bcl-2 expression in mitochondria. In addition, rapamycin significantly decreased cytochrome c release in from mitochondria into the cytosol. However, pretreatment of cells with the autophagy inhibitor, 3-methyladenine (3MA), remarkably increased CPF toxicity in these cells; this with correlated with increased expression of Bax and decreased expression of Bcl-2 in mitochondria. Our results suggest that CPF-induced cytotoxicity is modified by autophagy regulation and that rapamycin protects against CPF-induced apoptosis by enhancing autophagy. Pharmacologic induction of autophagy by rapamycin may be a useful treatment strategy in neurodegenerative disorders. - Highlights: ► Chlorpyrifos (CPF) is cytotoxic to SH-SY5Y cells ► CPF-induced cytotoxicity is mediated by

  2. How safe is the use of chlorpyrifos: Revelations through its effect on layer birds

    Science.gov (United States)

    Singh, P. P.; Kumar, Ashok; Chauhan, R. S.; Pankaj, P. K.

    2016-01-01

    Aim: The present study was aimed to investigate the immunological competence of chlorpyrifos (CPF) insecticide after oral administration in layer chickens. Materials and Methods: A total of 20 White Leghorn birds were given CPF in drinking water at 0.3 ppm/bird/day (no observable effect level dose) for a period of 3-month. Immune competence status of layer birds and chicks hatched from CPF-treated birds were estimated at 15 days interval in layer birds and monthly interval in chicks using immunological and biochemical parameters. Results: There was a significant decrease in values of total leukocytes count, absolute lymphocyte count, absolute heterophil count, total serum protein, serum albumin, serum globulin, and serum gamma globulin in the birds treated with CPF as compared to control. Similarly, immune competence tests such as lymphocyte stimulation test, oxidative burst assay, and enzyme-linked immunosorbent assay tests indicated lower immunity in birds treated with CPF as compared to control. Subsequently, chicks produced from CPF-treated birds were also examined for immune competence, but no significant difference was observed between chicks of both the groups. Conclusion: The exposure to CPF produced hemo-biochemical and other changes that could be correlated with changes in the immunological profile of layer chickens suggesting total stoppage of using CPF in poultry sheds. PMID:27536038

  3. Effect of pulse frequency and interval on the toxicity of chlorpyrifos to Daphnia magna.

    Science.gov (United States)

    Naddy, R B; Klaine, S J

    2001-11-01

    Due to the episodic nature in which organisms are exposed to non-point source pollutants, it is necessary to understand how they are affected by pulsed concentrations of contaminants. This is essential, as standard toxicity tests may not adequately simulate exposure scenarios for short-lived hydrophobic compounds, such as chlorpyrifos (CPF), a broad-spectrum organophosphate insecticide. Studies were conducted with 7-day old Daphnia magna for 7 days to evaluate the effect of pulse frequency and interval among multiple CPF exposures. Daphnids were exposed to a total exposure of either 12 h at 0.5 microg/l or 6 h at 1.0 microg/l nominal CPF, respectively, in all studies. For interval studies, D. magna were exposed to two pulses of CPF at each concentration, with 0-96-h intervals between pulses. For frequency studies, D. magna were exposed to each CPF concentration altering the pulse scheme by decreasing the exposure duration but increasing the number of pulses, keeping the total exposure time the same. The pulse interval between multiple pulses in these experiments was 24 h. Our results suggest that D. magna can withstand an acutely lethal CPF exposure provided that there is adequate time for recovery between exposures. PMID:11680745

  4. Neurobehavioral and biochemical changes in Nauphoeta cinerea following dietary exposure to chlorpyrifos.

    Science.gov (United States)

    Adedara, Isaac A; Rosemberg, Denis B; de Souza, Diego; Farombi, Ebenezer O; Aschner, Michael; Souza, Diogo O; Rocha, Joao B T

    2016-06-01

    The present study aimed to increase our understanding about the mode of toxic action of organophosphate pesticides in insects by evaluating the biochemical and neurobehavioral characteristics in Nauphoeta cinerea exposed to chlorpyrifos (CPF)-contaminated diet. The insects were exposed for 35 consecutive days to CPF at 0.078, 0.15625, 0.3125 and 0.625μg/g feed. Locomotor behavior was assessed for a 10-min trial in a novel arena and subsequently, biochemical analyses were carried out using the cockroaches' heads. In comparison to control, CPF-exposed cockroaches showed significant decreases in the total distance traveled, body rotation, turn angle and meandering, along with significant increase in the number of falls, time and episodes of immobility. The marked decrease in the exploratory profiles of CPF-exposed cockroaches was confirmed by track plots, whereas occupancy plot analyses showed a progressive dispersion at 0.15625μg/g feed group. Moreover, the heads of CPF-exposed cockroaches showed marked decrease in acetylcholinesterase activity and antioxidant status with concomitant significant elevation in dichlorofluorescein oxidation and lipid peroxidation levels in CPF-treated cockroaches. Gas Chromatography-Mass Spectrometry analyses revealed bioaccumulation of CPF in cockroaches exposed to concentrations above 0.078μg/g feed. The findings from this investigation showed N. cinerea as a value model organism for the risk assessment of environmental organophosphate contamination in insects. PMID:27155480

  5. Bacterial assisted degradation of chlorpyrifos: The key role of environmental conditions, trace metals and organic solvents.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran; Khan, Sher Jamal

    2016-03-01

    Wastewater from pesticide industries, agricultural or surface runoff containing pesticides and their residues has adverse environmental impacts. Present study demonstrates effect of petrochemicals and trace metals on chlorpyrifos (CP) biotransformation often released in wastewater of agrochemical industry. Biodegradation was investigated using bacterial strain Pseudomonas kilonensis SRK1 isolated from wastewater spiked with CP. Optimal environmental conditions for CP removal were CFU (306 × 10(6)), pH (8); initial CP concentration (150 mg/L) and glucose as additional carbon source. Among various organic solvents (petrochemicals) used in this study toluene has stimulatory effect on CP degradation process using SRK1, contrary to this benzene and phenol negatively inhibited degradation process. Application of metal ions (Cu (II), Fe (II) Zn (II) at low concentration (1 mg/L) took part in biochemical reaction and positively stimulated CP degradation process. Metal ions at high concentrations have inhibitory effect on degradation process. A first order growth model was shown to fit the data. It could be concluded that both type and concentration of metal ions and petrochemicals can affect CP degradation process. PMID:26692411

  6. A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats.

    Science.gov (United States)

    Tanvir, E M; Afroz, R; Chowdhury, Maz; Gan, S H; Karim, N; Islam, M N; Khalil, M I

    2016-09-01

    This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals. PMID:26519480

  7. 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

  8. An engineered microorganism can simultaneously detoxify cadmium, chlorpyrifos, and γ-hexachlorocyclohexane.

    Science.gov (United States)

    Yang, Chao; Yu, Huilei; Jiang, Hong; Qiao, Chuanling; Liu, Ruihua

    2016-07-01

    Many ecosystems are currently co-contaminated with heavy metals such as cadmium (Cd(2+) ) and pesticides such as chlorpyrifos (CP) and γ-hexachlorocyclohexane (γ-HCH). A feasible approach to remediate the combined pollution of heavy metals and pesticides is the use of γ-HCH degrading bacteria endowed with CP hydrolysis and heavy metal biosorption capabilities. In this work, a recombinant microorganism capable of simultaneously detoxifying Cd(2+) , CP, and γ-HCH was constructed by display of synthetic phytochelatins (EC20) and methyl parathion hydrolase (MPH) fusion protein on the cell surface of the γ-HCH degrading Sphingobium japonicum UT26 using the truncated ice nucleation protein (INPNC) as an anchoring motif. The surface localization of INPNC-EC20-MPH was verified by cell fractionation, Western blot analysis, immunofluorescence microscopy, and proteinase accessibility experiment. Expression of EC20 on the cell surface not only improved Cd(2+) binding but also alleviated the cellular toxicity of Cd(2+) . As expected, the rates of CP and γ-HCH degradation were reduced in the presence of Cd(2+) for cells without EC20 expression. However, expression of EC20 (higher Cd(2+) accumulation) significantly restored the levels of CP and γ-HCH degradation. These results demonstrated that surface display of EC20 enhanced not only Cd(2+) accumulation but also protected the recombinant strain against the toxic effects of Cd(2+) on CP and γ-HCH degradation. PMID:26648050

  9. Cardiotoxicity in rabbits after a low-level exposure to diazinon, propoxur, and chlorpyrifos.

    Science.gov (United States)

    Zafiropoulos, A; Tsarouhas, K; Tsitsimpikou, C; Fragkiadaki, P; Germanakis, I; Tsardi, M; Maravgakis, G; Goutzourelas, N; Vasilaki, F; Kouretas, D; Hayes, Aw; Tsatsakis, Am

    2014-12-01

    Lethal cardiac complications leading to death and various arrhythmias have been reported after organophosphate and/or carbamate poisonings. The present study focuses on the long-term effects of repeated low-level exposure to diazinon, propoxur, and chlorpyrifos (CPF) on cardiac function in rabbits. The yearly based experimental scheme of exposure consisted of two oral administration periods, lasting 3 months and 1 month each, interrupted by an 8-month washout period (total duration 12 months). At the end of the experimental scheme, the rabbits underwent an echocardiographic evaluation under sedation, after which they were killed and the tissue and serum samples were collected. A mild localized cardiotoxic effect was established by echocardiography for the three pesticides tested. Severe histological alterations were identified, especially in the diazinon-treated animals in agreement with increased persistence of this pesticide established in the cardiac tissue. In addition, all pesticides tested increased the oxidative stress and oxidative modifications in the genomic DNA content of the cardiac tissues, each one following a distinct mechanism.

  10. Characterization of the interaction between cadmium and chlorpyrifos with integrative techniques in incurring synergistic hepatoxicity.

    Directory of Open Access Journals (Sweden)

    Liqun Chen

    Full Text Available Mixture toxicity is an important issue for the risk assessment of environmental pollutants, for which an extensive amount of data are necessary in evaluating their potential adverse health effects. However, it is very hard to decipher the interaction between compounds due to limited techniques. Contamination of heavy metals and organophosphoric insecticides under the environmental and biological settings poses substantial health risk to humans. Although previous studies demonstrated the co-occurrence of cadmium (Cd and chlorpyrifos (CPF in environmental medium and food chains, their interaction and potentially synergistic toxicity remain elusive thus far. Here we integrated the approaches of thin-layer chromatography and (1H NMR to study the interaction between Cd(2+ and CPF in inducing hepatoxicity. A novel interaction was identified between Cd(2+ and CPF, which might be the bonding between Cd(2+ and nitrogen atom in the pyridine ring of CPF, or the chelation formation between one Cd(2+ and two CPF molecules. The Cd-CPF complex was conferred with distinct biological fate and toxicological performances from its parental components. We further demonstrated that the joint hepatoxicity of Cd ion and CPF was chiefly due to the Cd-CPF complex-facilitated intracellular transport associated with oxidative stress.

  11. Acetylcholinesterase inhibition and micronucleus frequency in oysters (Crassostrea corteziensis exposed to chlorpyrifos

    Directory of Open Access Journals (Sweden)

    AB Benitez-Trinidad1

    2014-09-01

    Full Text Available Chlorpyrifos (CPF is an Organophosphorous pesticide (OP that has been widely used for both agricultural and domestic pest control. To date, there is little information regarding the effects of this pesticide on aquatic organisms, particularly oysters. The aim of this study was to evaluate Acetylcholinesterase (AChE activity and Micronucleus (MN frequency in the oyster Crassostrea corteziensis in laboratory exposure with CPF (20, 40, 60, 80, and 160 μg/L and in a field study. The results showed that AChE was reduced 60 - 82 % in oysters exposed to CPF, relative to the negative control. Similar AChE results were observed in oysters collected from the Boca de Camichín Estuary in Nayarit, Mexico; with respect to genetic damage, evaluated through MN, treatment with CPF did not induce the MN frequency, nor did the oyster from the field study exhibit an increase in this biomarker. These results suggest that C. corteziensis is a sensitive model for evaluating the acute toxicity of OP in laboratory studies as well in the field. In addition, it generates prospects on studying mechanisms through which the oyster could possess resistance to genotoxic agents, as well as its being a reliable model for evaluating the genotoxic effects of xenobiotics through the MN technique.

  12. How safe is the use of chlorpyrifos: Revelations through its effect on layer birds

    Directory of Open Access Journals (Sweden)

    P. P. Singh

    2016-07-01

    Full Text Available Aim: The present study was aimed to investigate the immunological competence of chlorpyrifos (CPF insecticide after oral administration in layer chickens. Materials and Methods: A total of 20 White Leghorn birds were given CPF in drinking water at 0.3 ppm/bird/day (no observable effect level dose for a period of 3-month. Immune competence status of layer birds and chicks hatched from CPF-treated birds were estimated at 15 days interval in layer birds and monthly interval in chicks using immunological and biochemical parameters. Results: There was a significant decrease in values of total leukocytes count, absolute lymphocyte count, absolute heterophil count, total serum protein, serum albumin, serum globulin, and serum gamma globulin in the birds treated with CPF as compared to control. Similarly, immune competence tests such as lymphocyte stimulation test, oxidative burst assay, and enzyme-linked immunosorbent assay tests indicated lower immunity in birds treated with CPF as compared to control. Subsequently, chicks produced from CPF-treated birds were also examined for immune competence, but no significant difference was observed between chicks of both the groups. Conclusion: The exposure to CPF produced hemo-biochemical and other changes that could be correlated with changes in the immunological profile of layer chickens suggesting total stoppage of using CPF in poultry sheds.

  13. Utilization of microbial community potential for removal of chlorpyrifos: a review.

    Science.gov (United States)

    Yadav, Maya; Shukla, Awadhesh Kumar; Srivastva, Navnita; Upadhyay, Siddh Nath; Dubey, Suresh Kumar

    2016-08-01

    Chlorpyrifos (CP) is the most commonly used pesticide in agricultural fields worldwide. Exposure to CP and its metabolites creates severe neuron-disorders in human beings. Improper handling and uncontrolled application of CP by farmers have lead to the contamination of surface and ground water bodies. Biodegradation offers an efficient and cost effective method for the removal of CP and other toxic organophosphorus pesticides from the contaminated environment. The degradation of CP by various microorganisms has been investigated by several researchers over the past few years. This review presents a critical summary of the recent published results on the biodegradation of CP. A diverse range of bacterial species such as Agrobacterium sp., Alcaligenes faecalis, Enterobacter sp. Arthrobacter sp. Bacillus pumilus, Pseudomonas sp. etc., fungal species like Trichoderma viridae, Aspergillus niger, Verticillium sp., Acremonium sp. Cladosporium cladosporiodes, etc. and certain algal species viz. Chlorella vulgaris, Spirulina platensis, Synechocystis sp., etc., have been shown to degrade CP. The efficacy of these communities for CP degradation in batch and continuous modes has also been discussed but more studies are required on continuous reactors. Also, the available published information on kinetics of biodegradation of CP along with the available results on molecular biological approaches are discussed in this work. PMID:25782532

  14. A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats.

    Science.gov (United States)

    Tanvir, E M; Afroz, R; Chowdhury, Maz; Gan, S H; Karim, N; Islam, M N; Khalil, M I

    2016-09-01

    This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.

  15. Bacterial assisted degradation of chlorpyrifos: The key role of environmental conditions, trace metals and organic solvents.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran; Khan, Sher Jamal

    2016-03-01

    Wastewater from pesticide industries, agricultural or surface runoff containing pesticides and their residues has adverse environmental impacts. Present study demonstrates effect of petrochemicals and trace metals on chlorpyrifos (CP) biotransformation often released in wastewater of agrochemical industry. Biodegradation was investigated using bacterial strain Pseudomonas kilonensis SRK1 isolated from wastewater spiked with CP. Optimal environmental conditions for CP removal were CFU (306 × 10(6)), pH (8); initial CP concentration (150 mg/L) and glucose as additional carbon source. Among various organic solvents (petrochemicals) used in this study toluene has stimulatory effect on CP degradation process using SRK1, contrary to this benzene and phenol negatively inhibited degradation process. Application of metal ions (Cu (II), Fe (II) Zn (II) at low concentration (1 mg/L) took part in biochemical reaction and positively stimulated CP degradation process. Metal ions at high concentrations have inhibitory effect on degradation process. A first order growth model was shown to fit the data. It could be concluded that both type and concentration of metal ions and petrochemicals can affect CP degradation process.

  16. Rosiglitazone inhibits chlorpyrifos-induced apoptosis via modulation of the oxidative stress and inflammatory response in SH-SY5Y cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Eun [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Park, Jae Hyeon; Jang, Sea Jeong [Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Koh, Hyun Chul, E-mail: hckoh@hanyang.ac.kr [Department of Pharmacology, College of Medicine, Hanyang University, Seoul (Korea, Republic of); Hanyang Biomedical Research Institute, Seoul (Korea, Republic of); Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2014-07-15

    Oxidative stress can lead to expression of inflammatory transcription factors, which are important regulatory elements in the induction of inflammatory responses. One of the transcription factors, nuclear transcription factor kappa-B (NF-κB) plays a significant role in the inflammation regulatory process. Inflammatory cell death has been implicated in neuronal cell death in some neurodegenerative disorders such as Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying apoptosis initiated by chlorpyrifos (CPF)-mediated oxidative stress. Based on the cytotoxic mechanism of CPF, we examined the neuroprotective effects of rosiglitazone (RGZ), a peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist, against CPF-induced neuronal cell death. The treatment of SH-SY5Y cells with CPF induced oxidative stress. In addition, CPF activated the p38, JNK and ERK mitogen-activated protein kinases (MAPKs), and induced increases in the inflammatory genes such as COX-2 and TNF-α. CPF also induced nuclear translocation of NF-κB and inhibitors of NF-κB abolished the CPF-induced COX-2 expression. Pretreatment with RGZ significantly reduced ROS generation and enhanced HO-1 expression in CPF-exposed cells. RGZ blocked the activation of both p38 and JNK signaling, while ERK activation was strengthened. RGZ also attenuated CPF-induced cell death through the reduction of NF-κB-mediated proinflammatory factors. Results from this study suggest that RGZ may exert an anti-apoptotic effect against CPF-induced cytotoxicity by attenuation of oxidative stress as well as inhibition of the inflammatory cascade via inactivation of signaling by p38 and JNK, and NF-κB. - Highlights: • CPF induces apoptotic cell death in SH-SY5Y cells • ROS involved in CPF-mediated apoptotic cell death • Inflammation involved in CPF-mediated apoptotic cell death • Rosiglitazone modulates ROS and inflammatory response in CPF-treated cells.

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

    Science.gov (United States)

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

    2015-06-01

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

  18. Time-resolved fluorescence sensing of pesticides chlorpyrifos, crotoxyphos and endosulfan by the luminescent Eu(III)-8-allyl-3-carboxycoumarin probe

    Science.gov (United States)

    Azab, Hassan A.; Khairy, Gasser M.; Kamel, Rasha M.

    2015-09-01

    This work describes the application of time resolved fluorescence in microtiter plates for investigating the interactions of europium-allyl-3-carboxycoumarin with pesticides chlorpyrifos, endosulfan and crotoxyphos. Stern-Volmer studies at different temperatures for chlorpyrifos and crotoxyphos shows dynamic and static quenching mechanisms respectively. Direct methods for the determination of the pesticides under investigation have been developed using the luminescence variations of the probe in solution. The detection limits are 6.53, 0.004, 3.72 μmol/L for chlorpyrifos, endosulfan, and crotoxyphos, respectively. The binding constants and thermodynamic parameters of the pesticides with probe were evaluated. A thermodynamic analysis showed that the reaction is spontaneous with negative ΔG. Effect of some relevant interferents on the detection of pesticides has been investigated. The new method was applied to the determination of the pesticides in different types of water samples (tap, mineral, and waste water).

  19. Efficacies of spinosad and a combination of chlorpyrifos-methyl and deltamethrin against phosphine-resistant Rhyzopertha dominica (Coleoptera: Bostrichidae) and Tribolium castaneum (Coleoptera: Tenebrionidae) on wheat.

    Science.gov (United States)

    Bajracharya, N S; Opit, George P; Talley, J; Jones, C L

    2013-10-01

    Highly phosphine-resistant populations of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) have recently been found in Oklahoma grain storage facilities. These findings necessitate development of a phosphine resistance management strategy to ensure continued effective use of phosphine. Therefore, we investigated the efficacies of two grain insecticides, namely, spinosad applied at label rate of 1 ppm and a mixture of chlorpyrifos-methyl and deltamethrin applied at label rates of 3 and 0.5 ppm, respectively, against highly phosphine-resistant R. dominica and T. castaneum. Adult mortality and progeny production suppression of spinosad- or chlorpyrifos-methyl + deltamethrin mixture-treated wheat that had been stored for 2, 84, 168, 252, and 336 d posttreatment were assessed. We found that both spinosad and chlorpyrifos-methyl + deltamethrin were effective against phosphine-resistant R. dominica and caused 83-100% mortality and also caused total progeny production suppression for all storage periods. Spinosad was not effective against phosphine-resistant T. castaneum; the highest mortality observed was only 3% for all the storage periods. Chlorpyrifos-methyl + deltamethrin was effective against phosphine-resistant T. castaneum only in treated wheat stored for 2 and 84 d, where it caused 93-99% mortality. However, chlorpyrifos-methyl + deltamethrin was effective and achieved total suppression of progeny production in T. castaneum for all the storage periods. Spinosad was not as effective as chlorpyrifos-methyl + deltamethrin mixture at suppressing progeny production of phosphine-resistant T. castaneum. These two insecticides can be used in a phosphine resistance management strategy for R. dominica and T. castaneum in the United States.

  20. Fitness Effects of Chlorpyrifos in the Damselfly Enallagma cyathigerum Strongly Depend upon Temperature and Food Level and Can Bridge Metamorphosis.

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    Lizanne Janssens

    Full Text Available Interactions between pollutants and suboptimal environmental conditions can have severe consequences for the toxicity of pollutants, yet are still poorly understood. To identify patterns across environmental conditions and across fitness-related variables we exposed Enallagma cyathigerum damselfly larvae to the pesticide chlorpyrifos at two food levels or at two temperatures and quantified four fitness-related variables (larval survival, development time, mass at emergence and adult cold resistance. Food level and temperature did not affect survival in the absence of the pesticide, yet the pesticide reduced survival only at the high temperature. Animals reacted to the pesticide by accelerating their development but only at the high food level and at the low temperature; at the low food level, however, pesticide exposure resulted in a slower development. Chlorpyrifos exposure resulted in smaller adults except in animals reared at the high food level. Animals reared at the low food level and at the low temperature had a higher cold resistance which was not affected by the pesticide. In summary our study highlight that combined effects of exposure to chlorpyrifos and the two environmental conditions (i were mostly interactive and sometimes even reversed in comparison with the effect of the environmental condition in isolation, (ii strongly differed depending on the fitness-related variable under study, (iii were not always predictable based on the effect of the environmental condition in isolation, and (iv bridged metamorphosis depending on which environmental condition was combined with the pesticide thereby potentially carrying over from aquatic to terrestrial ecosystems. These findings are relevant when extrapolating results of laboratory tests done under ideal environmental conditions to natural communities.

  1. Urinary biomarker concentrations of captan, chlormequat, chlorpyrifos and cypermethrin in UK adults and children living near agricultural land.

    Science.gov (United States)

    Galea, Karen S; MacCalman, Laura; Jones, Kate; Cocker, John; Teedon, Paul; Cherrie, John W; van Tongeren, Martie

    2015-01-01

    There is limited information on the exposure to pesticides experienced by UK residents living near agricultural land. This study aimed to investigate their pesticide exposure in relation to spray events. Farmers treating crops with captan, chlormequat, chlorpyrifos or cypermethrin provided spray event information. Adults and children residing ≤100 m from sprayed fields provided first-morning void urine samples during and outwith the spray season. Selected samples (1-2 days after a spray event and at other times (background samples)) were analysed and creatinine adjusted. Generalised Linear Mixed Models were used to investigate if urinary biomarkers of these pesticides were elevated after spray events. The final data set for statistical analysis contained 1518 urine samples from 140 participants, consisting of 523 spray event and 995 background samples which were analysed for pesticide urinary biomarkers. For captan and cypermethrin, the proportion of values below the limit of detection was greater than 80%, with no difference between spray event and background samples. For chlormequat and chlorpyrifos, the geometric mean urinary biomarker concentrations following spray events were 15.4 μg/g creatinine and 2.5 μg/g creatinine, respectively, compared with 16.5 μg/g creatinine and 3.0 μg/g creatinine for background samples within the spraying season. Outwith the spraying season, concentrations for chlorpyrifos were the same as those within spraying season backgrounds, but for chlormequat, lower concentrations were observed outwith the spraying season (12.3 μg/g creatinine). Overall, we observed no evidence indicative of additional urinary pesticide biomarker excretion as a result of spray events, suggesting that sources other than local spraying are responsible for the relatively low urinary pesticide biomarkers detected in the study population.

  2. Comparative effects of parathion and chlorpyrifos on extracellular endocannabinoid levels in rat hippocampus: Influence on cholinergic toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jing [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK (United States); Parsons, Loren [Committee on Neurobiology of Affective Disorders, The Scripps Research Institute, La Jolla, CA (United States); Pope, Carey, E-mail: carey.pope@okstate.edu [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK (United States)

    2013-11-01

    Parathion (PS) and chlorpyrifos (CPF) are organophosphorus insecticides (OPs) that elicit acute toxicity by inhibiting acetylcholinesterase (AChE). Endocannabinoids (eCBs, N-arachidonoylethanolamine, AEA; 2-arachidonoylglycerol, 2AG) can modulate neurotransmission by inhibiting neurotransmitter release. We proposed that differential inhibition of eCB-degrading enzymes (fatty acid amide hydrolase, FAAH, and monoacylglycerol lipase, MAGL) by PS and CPF leads to differences in extracellular eCB levels and toxicity. Microdialysis cannulae were implanted into hippocampus of adult male rats followed by treatment with vehicle (peanut oil, 2 ml/kg, sc), PS (27 mg/kg) or CPF (280 mg/kg) 6–7 days later. Signs of toxicity, AChE, FAAH and MAGL inhibition, and extracellular levels of AEA and 2AG were measured 2 and 4 days later. Signs were noted in PS-treated rats but not in controls or CPF-treated rats. Cholinesterase inhibition was extensive in hippocampus with PS (89–90%) and CPF (78–83%) exposure. FAAH activity was also markedly reduced (88–91%) by both OPs at both time-points. MAGL was inhibited by both OPs but to a lesser degree (35–50%). Increases in extracellular AEA levels were noted after either PS (about 2-fold) or CPF (about 3-fold) while lesser treatment-related 2-AG changes were noted. The cannabinoid CB1 receptor antagonist/inverse agonist AM251 (3 mg/kg, ip) had no influence on functional signs after CPF but markedly decreased toxicity in PS-treated rats. The results suggest that extracellular eCBs levels can be markedly elevated by both PS and CPF. CB1-mediated signaling appears to play a role in the acute toxicity of PS but the role of eCBs in CPF toxicity remains unclear. - Highlights: • Chlorpyrifos and parathion both extensively inhibited hippocampal cholinesterase. • Functional signs were only noted with parathion. • Chlorpyrifos and parathion increased hippocampal extracellular anandamide levels. • 2-Arachidonoylglycerol levels were

  3. Evaluation of chronic chlorpyrifos-induced reproductive toxicity in male Wistar rat: protective effects of vitamin C

    OpenAIRE

    Mohammed M. Sulaiman; Mohammed Y. Fatihu; Joseph O. Ayo; Suleiman F. Ambali; Muftau Shittu; Lukuman S. Yaqub

    2013-01-01

    The aim of the present study was to evaluate the effect of vitamin C on reproductive toxicity, induced by chronic chlorpyrifos (CPF) exposure in male Wistar rats. Twenty adult male Wistar rats were divided into 4 groups of 5 animals in each group. Group I received soya oil (2 ml/kg); group II was given vitamin C only (100 mg/kg); group III was administered CPF only (10.6 mg/kg; ~1/8th LD50), while group IV was pretreated with vitamin C and then exposed to CPF, 30 min later. The regimens were ...

  4. Chlorpyrifos for control of the short-nosed cattle louse, Haematopinus eurysternus (Nitzsch) (Anoplura, Haematopinidae) during winter.

    OpenAIRE

    Khan, M. A.; Schaalje, G. B.

    1985-01-01

    Two groups (A and C) of range cows were treated in February with chlorpyrifos (16 mL Dursban 44/cow) for the control of heavy infestations of the short-nosed cattle louse. Group A was treated in 1977 and group C in 1979 and each treated group was compared with a separate untreated group. Some of the treated cows were identified as carriers of louse infestation (subgroups A1 and C1), while others were noncarriers (subgroups A2 and C2). The maximum level of reduction in louse populations was 99...

  5. Contamination of fresh water fish “Schizothorax niger” with chlorpyrifos from “Dal Lake” basins, India

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    Banday Muddasir

    2012-12-01

    Full Text Available Dal Lake a Sub-Himalyan urban Lake is one of the most beautiful lakes of India and second largest in Jammu & Kashmir. Intensive farming practiced in the surrounding area of Dal Lake and its floating gardensleads to an enhanced vulnerability of crops to pests and indiscriminate use of pesticides. Possible transfer of these hazardous molecules from vegetable fields to the aquatic environment of the Lake, poses a potential threat to the aquatic species and human health as well. In the present investigation conducted from 2008 to 2010, 135 samples of fish including 81 samples of schizothorax niger ( Algaad / Kasheer Gaad and 54 samples of Cyprinus carpii (Punjab Gaad were collected from three basins of Dal Lake namely Hazratbal, Nigeen and Cheshmashahi basin. The samples were analyzed for seven commonly used pesticides viz. Butachlor, γHCH,Chlorpyrifos, Hexaconazole, Endosulfan 1, Endosulfan 2 and Dichlorvas. Detection and quantification of pesticide residues was performed by GC-MS/MS (Thermofinnigan Polaris Q type equipped with Ni ECD. It was found that 73 samples (54.07% out of 135 were contaminated with chlorpyrifos an organophosphate pesticide with mean concentration of (0.0009 ± 0.0010ng/kg with concentration ranging from undetected to 0.003ng/kg. The highest concentration was found in Hazratbal basin in 2009 (0.002 ± 0.001ng/kg. The results also reveal that level of pesticide was higher in pesticide use season than non use season except in 2009 when levels were same. With respect to basins the results show that mean concentration of chlorpyrifos level was higher in pesticide application season than non application season except in Nigeen basin in 2008 and 2009 where levels were same (0.001±0.001ng/kg and in Hazratbal basin in 2010 where levels were same (0.001±0.001ng/kg. The results indicate a sub acute exposure of chlorpyrifos in a locally consumed Schizothorax niger and not in Cyprinus carpii. These findings suggest that low dose

  6. Diploid and triploid African catfish (Clarias gariepinus) differ in biomarker responses to the pesticide chlorpyrifos.

    Science.gov (United States)

    Karami, Ali; Goh, Yong-Meng; Jahromi, Mohammad Faseleh; Lazorchak, James M; Abdullah, Maha; Courtenay, Simon C

    2016-07-01

    The impacts of environmental stressors on polyploid organisms are largely unknown. This study investigated changes in morphometric, molecular, and biochemical parameters in full-sibling diploid and triploid African catfish (Clarias gariepinus) in response to chlorpyrifos (CPF) exposures. Juvenile fish were exposed to three concentrations of CPF (mean measured μg/L (SD): 9.71 (2.27), 15.7 (3.69), 31.21 (5.04)) under a static-renewal condition for 21days. Diploid control groups had higher hepatosomatic index (HSI), plasma testosterone (T), and brain GnRH and cyp19a2 expression levels than triploids. In CPF-exposed groups, changes in HSI, total weight and length were different between the diploid and triploid fish. In contrast, condition factor did not alter in any of the treatments, while visceral-somatic index (VSI) changed only in diploids. In diploid fish, exposure to CPF did not change brain 11β-hsd2, ftz-f1, foxl2, GnRH or cyp19a2 mRNA levels, while reduced tph2 transcript levels compared to the control group. In contrast, 11β-hsd2 and foxl2 expression levels were changed in triploids following CPF exposures. In diploids, plasma T levels showed a linear dose-response reduction across CPF treatments correlating with liver weight and plasma total cholesterol concentrations. In contrast, no changes in plasma cholesterol and T concentrations were observed in triploids. Plasma cortisol and 17-β estradiol (E2) showed no response to CPF exposure in either ploidy. Results of this first comparison of biomarker responses to pesticide exposure in diploid and polyploid animals showed substantial differences between diploid and triploid C. gariepinus. PMID:26994807

  7. Fluorescent Chemosensors for Selective and Sensitive Detection of Phosmet/Chlorpyrifos with Octahedral Ni(2+) Complexes.

    Science.gov (United States)

    Raj, Pushap; Singh, Amanpreet; Kaur, Kamalpreet; Aree, Thammarat; Singh, Ajnesh; Singh, Narinder

    2016-05-16

    The hexadentate ligands H2L1-L3 with mixed S, N, O donor sites and possessing substituents having either "no" or electron-releasing/withdrawing nature at terminal ends are synthesized. The ligands H2L1-L3 were tested for binding with library of metal ions, wherein maximum efficiency was observed with Ni(2+), and it motivated us to prepare the Ni(2+) complexes. The ligand H2L1 underwent deprotonation and formed binuclear complex when interacted with Ni(2+) as evident from its crystal structure. The H2L2 and H2L3 having electron-withdrawing/electron releasing groups, respectively, were also deprotonated; however, they afforded mononuclear complexes with Ni(2+) ion. This signifies the importance of steric parameters instead of electronic factors in these particular cases. Impressed by differential behavior of complexes of H2L1 and H2L2/H2L3 with Ni(2+) and their photophysical and electrochemical properties, all the metal complexes were studied for their chemosensing ability. Nowadays with increased use of organophosphate, there is alarming increase of these agents in the environment, and thus we require efficient technique to estimate the level of these agents with high sensitivity and selectivity in aqueous medium. The Ni(2+) complexes with hydrophobic nature were suspended into aqueous medium for testing them as sensor for organophosphate. The (L1)2.(Ni(2+))2 could sense phosmet with detection limit of 44 nM, whereas L2.Ni(2+) and L3.Ni(2+) exhibited the detection limits of 62 and 71 nM, respectively, for chlorpyrifos. PMID:27115348

  8. Fluorescent Chemosensors for Selective and Sensitive Detection of Phosmet/Chlorpyrifos with Octahedral Ni(2+) Complexes.

    Science.gov (United States)

    Raj, Pushap; Singh, Amanpreet; Kaur, Kamalpreet; Aree, Thammarat; Singh, Ajnesh; Singh, Narinder

    2016-05-16

    The hexadentate ligands H2L1-L3 with mixed S, N, O donor sites and possessing substituents having either "no" or electron-releasing/withdrawing nature at terminal ends are synthesized. The ligands H2L1-L3 were tested for binding with library of metal ions, wherein maximum efficiency was observed with Ni(2+), and it motivated us to prepare the Ni(2+) complexes. The ligand H2L1 underwent deprotonation and formed binuclear complex when interacted with Ni(2+) as evident from its crystal structure. The H2L2 and H2L3 having electron-withdrawing/electron releasing groups, respectively, were also deprotonated; however, they afforded mononuclear complexes with Ni(2+) ion. This signifies the importance of steric parameters instead of electronic factors in these particular cases. Impressed by differential behavior of complexes of H2L1 and H2L2/H2L3 with Ni(2+) and their photophysical and electrochemical properties, all the metal complexes were studied for their chemosensing ability. Nowadays with increased use of organophosphate, there is alarming increase of these agents in the environment, and thus we require efficient technique to estimate the level of these agents with high sensitivity and selectivity in aqueous medium. The Ni(2+) complexes with hydrophobic nature were suspended into aqueous medium for testing them as sensor for organophosphate. The (L1)2.(Ni(2+))2 could sense phosmet with detection limit of 44 nM, whereas L2.Ni(2+) and L3.Ni(2+) exhibited the detection limits of 62 and 71 nM, respectively, for chlorpyrifos.

  9. Biotreatment of chlorpyrifos in a bench scale bioreactor using Psychrobacter alimentarius T14.

    Science.gov (United States)

    Khalid, Saira; Hashmi, Imran

    2016-01-01

    Bacteria tolerant to high pesticide concentration could be used for designing an efficient treatment technology. Bacterial strains T14 was isolated from pesticide-contaminated soil in mineral salt medium (MSM) and identified as Psychrobacter alimentarius T14 using 16S rRNA gene sequence analysis. Bench scale bioreactor was evaluated for biotreatment of high Chlorpyrifos (CP) concentration using P. alimentarius T14. Effect of various parameters on bioreactor performance was examined and optimum removal was observed at optical density (OD600 nm): 0.8; pH: 7.2; CP concentration: 300 mg L(-1) and hydraulic retention time: 48 h. At optimum conditions, 70.3/79% of CP/chemical oxygen demand (COD) removal was achieved in batch bioreactors. In addition, P. alimentarius T14 achieved 95/91, 62.3/75, 69.8/64% CP/COD removal efficiency with addition of CS (co-substrates), CS1 (yeast extract + synthetic wastewater), CS2 (glucose + synthetic wastewater) and CS3 (yeast extract), respectively. Addition of CS1 to bioreactor could accelerate CP removal rate up to many cycles with considerable efficiency. However, accumulation of 3, 5, 6-trichloro-2-pyridinol affects reactor performance in cyclic mode. First-order rate constant k1 0.062 h(-1) and t1/2 11.1 h demonstrates fast degradation. Change in concentration of total chlorine and nitrogen could be the result of complete mineralization. Photodegradation of CP in commercial product was more than its pure form. Commercial formulation accelerated photodegradation process; however no effect on biodegradation process was observed. After bio-photodegradation, negligible toxicity for seeds of Triticum aestivum was observed. Study suggests an efficient treatment of wastewater containing CP and its metabolites in batch bioreactors could be achieved using P. alimentarius.

  10. Co-treatment of chlorpyrifos and lead induce serum lipid disorders in rats: Alleviation by taurine.

    Science.gov (United States)

    Akande, Motunrayo G; Aliu, Yusuf O; Ambali, Suleiman F; Ayo, Joseph O

    2016-07-01

    The aim of this study was to investigate the effects of taurine (TA) on serum lipid profiles following chronic coadministration of chlorpyrifos (CP) and lead acetate (Pb) in male Wistar rats. Fifty rats randomly distributed into five groups served as subjects. Distilled water (DW) was given to DW group, while soya oil (SO; 1 mL kg(-1)) was given to SO group. The TA group was treated with TA (50 mg kg(-1)). The CP + Pb group was administered sequentially with CP (4.25 mg kg(-1); 1/20th median lethal dose (LD50)) and Pb at 233.25 mg kg(-1) (1/20th LD50), while the TA + CP + Pb group received TA (50 mg kg(-1)), CP (4.25 mg kg(-1)), and Pb (233.25 mg kg(-1)) sequentially. The treatments were administered once daily by oral gavage for 16 weeks. The rats were euthanised, and the blood samples were collected at the termination of the study. Sera obtained from the blood samples were analyzed for total cholesterol, high-density lipoprotein cholesterol, triglycerides, and malondialdehyde, and also the activities of serum antioxidant enzymes including superoxide dismutase, catalase and glutathione peroxidase were analyzed. The low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, and atherogenic index were calculated. The results showed that CP and Pb induced alterations in the serum lipid profiles and evoked oxidative stress. TA alleviated the disruptions in the serum lipid profiles of the rats partially by mitigating oxidative stress. It was concluded that TA may be used for prophylaxis against serum lipid disorders in animals that were constantly co-exposed to CP and Pb in the environment. PMID:25537622

  11. Prenatal chlorpyrifos exposure alters motor behavior and ultrasonic vocalization in cd-1 mouse pups

    Directory of Open Access Journals (Sweden)

    Calamandrei Gemma

    2009-03-01

    Full Text Available Abstract Background Chlorpyrifos (CPF is a non-persistent organophosphate (OP largely used as pesticide. Studies from animal models indicate that CPF is a developmental neurotoxicant able to target immature central nervous system at dose levels well below the threshold of systemic toxicity. So far, few data are available on the potential short- and long-term adverse effects in children deriving from low-level exposures during prenatal life and infancy. Methods Late gestational exposure [gestational day (GD 14–17] to CPF at the dose of 6 mg/kg was evaluated in CD-1 mice during early development, by assessment of somatic and sensorimotor maturation [reflex-battery on postnatal days (PNDs 3, 6, 9, 12 and 15] and ultrasound emission after isolation from the mother and siblings (PNDs 4, 7 and 10. Pups' motor skills were assessed in a spontaneous activity test on PND 12. Maternal behavior of lactating dams in the home cage and in response to presentation of a pup previously removed from the nest was scored on PND 4, to verify potential alterations in maternal care directly induced by CPF administration. Results As for the effects on the offspring, results indicated that on PND 10, CPF significantly decreased number and duration of ultrasonic calls while increasing latency to emit the first call after isolation. Prenatal CPF also reduced motor behavior on PND 12, while a tendency to hyporeflexia was observed in CPF pups by means of reflex-battery scoring. Dams administered during gestation with CPF showed baseline levels of maternal care comparable to those of controls, but higher levels of both pup-directed (licking and explorative (wall rearing responses. Conclusion Overall our results are consistent with previous epidemiological data on OP neurobehavioral toxicity, and also indicate ultrasonic vocalization as an early marker of CPF exposure during development in rodent studies, with potential translational value to human infants.

  12. Inhibition, recovery and oxime-induced reactivation of muscle esterases following chlorpyrifos exposure in the earthworm Lumbricus terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Collange, B. [Universite d' Avignon et des Pays de Vaucluse, UMR 406 Abeilles et Environnement, Site AGROPARC, F-84914, Avignon Cede 09 (France); Wheelock, C.E. [Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE 171 77, Stockholm (Sweden); Rault, M.; Mazzia, C. [Universite d' Avignon et des Pays de Vaucluse, UMR 406 Abeilles et Environnement, Site AGROPARC, F-84914, Avignon Cede 09 (France); Capowiez, Y. [INRA, Unite PSH, Site AGROPARC, F-84914 Avignon Cedex 09 (France); Sanchez-Hernandez, J.C., E-mail: juancarlos.sanchez@uclm.e [Laboratory of Ecotoxicology, Faculty of Environmental Science, University of Castilla-La Mancha, Avda. Carlos III s/n, 45071, Toledo (Spain)

    2010-06-15

    Assessment of wildlife exposure to organophosphorus (OP) pesticides generally involves the measurement of cholinesterase (ChE) inhibition, and complementary biomarkers (or related endpoints) are rarely included. Herein, we investigated the time course inhibition and recovery of ChE and carboxylesterase (CE) activities in the earthworm Lumbricus terrestris exposed to chlorpyrifos, and the ability of oximes to reactivate the phosphorylated ChE activity. Results indicated that these esterase activities are a suitable multibiomarker scheme for monitoring OP exposure due to their high sensitivity to OP inhibition and slow recovery to full activity levels following pesticide exposure. Moreover, oximes reactivated the inhibited ChE activity of the earthworms exposed to 12 and 48 mg kg{sup -1} chlorpyrifos during the first week following pesticide exposure. This methodology is useful for providing evidence for OP-mediated ChE inhibition in individuals with a short history of OP exposure (<=1 week); resulting a valuable approach for assessing multiple OP exposure episodes in the field. - Esterase inhibition combined with oxime reactivation methods is a suitable approach for monitoring organophosphate contamination

  13. Genome-wide gene expression analysis in response to organophosphorus pesticide chlorpyrifos and diazinon in C. elegans.

    Directory of Open Access Journals (Sweden)

    Ana Viñuela

    Full Text Available Organophosphorus pesticides (OPs were originally designed to affect the nervous system by inhibiting the enzyme acetylcholinesterase, an important regulator of the neurotransmitter acetylcholine. Over the past years evidence is mounting that these compounds affect many other processes. Little is known, however, about gene expression responses against OPs in the nematode Caenorhabditis elegans. This is surprising because C. elegans is extensively used as a model species in toxicity studies. To address this question we performed a microarray study in C. elegans which was exposed for 72 hrs to two widely used Ops, chlorpyrifos and diazinon, and a low dose mixture of these two compounds. Our analysis revealed transcriptional responses related to detoxification, stress, innate immunity, and transport and metabolism of lipids in all treatments. We found that for both compounds as well as in the mixture, these processes were regulated by different gene transcripts. Our results illustrate intense, and unexpected crosstalk between gene pathways in response to chlorpyrifos and diazinon in C. elegans.

  14. Dual-template magnetic molecularly imprinted particles with multi-hollow structure for the detection of dicofol and chlorpyrifos-methyl.

    Science.gov (United States)

    Yang, Tao; Feng, Shun; Lu, Yi; Yin, Chao; Wang, Jide

    2016-06-01

    In this work, a novel dual-template magnetic molecularly imprinted polymer particle for dicofol and chlorpyrifos-methyl was prepared through oil-in-water emulsifier-free emulsion technology. The resulting magnetic particles were characterized with electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. It was found that as-prepared particles were well-shaped spheres with multi-hollow structures and of a size around 125 μm. Meanwhile it showed a good magnetic sensitivity. The results testified that multi-hollow magnetic molecularly imprinted polymers possessed excellent recognition capacity and fast kinetic binding behavior to the objective molecules. The maximum binding amounts toward dicofol and chlorpyrifos-methyl were 31.46 and 25.23 mg/g, respectively. The feasibility of the use of the particles as a solid-phase extraction sorbent was evaluated. Satisfactory recoveries ranging from 90.62 to 111.47 and 91.07 to 94.03% were obtained for dicofol and chlorpyrifos-methyl, respectively, spiked at three concentration levels from real samples. The Langmuir isotherm equation provided an excellent fit to the equilibrium sorption data of either dicofol or chlorpyrifos-methyl. It provided a novel way to advise dual-template magnetic molecularly imprinted polymer particles to adsorb pesticides with high selectivity.

  15. Biodegradation of chlorpyrifos and its hydrolysis product 3,5,6-trichloro-2-pyridinol using a novel bacterium Ochrobactrum sp. JAS2: A proposal of its metabolic pathway.

    Science.gov (United States)

    Abraham, Jayanthi; Silambarasan, Sivagnanam

    2016-01-01

    Biodegradation of chlorpyrifos and its major metabolite 3,5,6-trichloro-2-pyridinol (TCP) were studied with a novel bacterial strain JAS2 isolated from paddy rhizosphere soil. The molecular characterization based on 16S rRNA gene sequence homology confirmed its identity as Ochrobactrum sp. JAS2. The JAS2 strain degraded 300mgl(-1) of chlorpyrifos within 12h of incubation in the aqueous medium and it produced the TCP metabolite. However, after 72h of incubation TCP was also completely degraded by the JAS2 strain. A tentative degradation pathway of chlorpyrifos by Ochrobactrum sp. JAS2 has been proposed on basis of GC-MS analysis. The complete degradation of chlorpyrifos occurred within 24h in the soil spiked with and without addition of nutrients inoculated with Ochrobactrum sp. JAS2. TCP was obtained in both the studies which was degraded completely by 96h in the soil spiked with nutrients and whereas 120h in absence of nutrients in the soil. The mpd gene which is responsible for organophosphorus hydrolase production was identified. The isolates Ochrobactrum sp. JAS2 also exhibited a time dependent increase in the amount of tricalcium phosphate solubilization in Pikovskaya's medium. Further screening of the strain JAS2 for auxiliary plant growth promoting activities revealed its remarkable capability of producing the indole acetic acid (IAA), hydrogen cyanide (HCN) and ammonia.

  16. Repeated exposure to neurotoxic levels of chlorpyrifos alters hippocampal expression of neurotrophins and neuropeptides.

    Science.gov (United States)

    Lee, Young S; Lewis, John A; Ippolito, Danielle L; Hussainzada, Naissan; Lein, Pamela J; Jackson, David A; Stallings, Jonathan D

    2016-01-18

    Chlorpyrifos (CPF), an organophosphorus pesticide (OP), is one of the most widely used pesticides in the world. Subchronic exposures to CPF that do not cause cholinergic crisis are associated with problems in cognitive function (i.e., learning and memory deficits), but the biological mechanism(s) underlying this association remain speculative. To identify potential mechanisms of subchronic CPF neurotoxicity, adult male Long Evans (LE) rats were administered CPF at 3 or 10mg/kg/d (s.c.) for 21 days. We quantified mRNA and non-coding RNA (ncRNA) expression profiles by RNA-seq, microarray analysis and small ncRNA sequencing technology in the CA1 region of the hippocampus. Hippocampal slice immunohistochemistry was used to determine CPF-induced changes in protein expression and localization patterns. Neither dose of CPF caused overt clinical signs of cholinergic toxicity, although after 21 days of exposure, cholinesterase activity was decreased to 58% or 13% of control levels in the hippocampus of rats in the 3 or 10mg/kg/d groups, respectively. Differential gene expression in the CA1 region of the hippocampus was observed only in the 10mg/kg/d dose group relative to controls. Of the 1382 differentially expressed genes identified by RNA-seq and microarray analysis, 67 were common to both approaches. Differential expression of six of these genes (Bdnf, Cort, Crhbp, Nptx2, Npy and Pnoc) was verified in an independent CPF exposure study; immunohistochemistry demonstrated that CRHBP and NPY were elevated in the CA1 region of the hippocampus at 10mg/kg/d CPF. Gene ontology enrichment analysis suggested association of these genes with receptor-mediated cell survival signaling pathways. miR132/212 was also elevated in the CA1 hippocampal region, which may play a role in the disruption of neurotrophin-mediated cognitive processes after CPF administration. These findings identify potential mediators of CPF-induced neurobehavioral deficits following subchronic exposure to CPF at

  17. Comparative pharmacokinetics of chlorpyrifos versus its major metabolites following oral administration in the rat

    International Nuclear Information System (INIS)

    Chlorpyrifos (CPF) is a commonly used diethylphosphorothionate organophosphorus (OP) insecticide. Diethylphosphate (DEP), diethylthiophosphate (DETP) and 3,5,6-trichloro-2-pyridinol (TCPy) are products of both in vivo metabolism and environmental degradation of CPF and are routinely measured in urine as biomarkers of exposure. Hence, urinary biomonitoring of TCPy, DEP and DETP may be reflective of an individual's contact with both the parent pesticide and exposure to these metabolites in the environment. In the current study, simultaneous dosing of 13C- or 2H-isotopically labeled CPF (13C-labeled CPF, 5 13C on the TCPy ring; or 2H-labeled CPF, diethyl-D10 (deuterium labeled) on the side chain) were exploited to directly compare the pharmacokinetics and metabolism of CPF with TCPy, and DETP. The key objective in the current study was to quantitatively evaluate the pharmacokinetics of the individual metabolites relative to their formation following a dose of CPF. Individual metabolites were co-administered (oral gavage) with the parent compound at equal molar doses (14 μmol/kg; ∼5 mg/kg CPF). Major differences in the pharmacokinetics between CPF and metabolite doses were observed within the first 3 h of exposure, due to the required metabolism of CPF to initially form TCPy and DETP. Nonetheless, once a substantial amount of CPF has been metabolized (≥3 h post-dosing) pharmacokinetics for both treatment groups and metabolites were very comparable. Urinary excretion rates for orally administered TCPy and DETP relative to 13C-CPF or 2H-CPF derived 13C-TCPy and 2H-DETP were consistent with blood pharmacokinetics, and the urinary clearance of metabolite dosed groups were comparable with the results for the 13C- and 2H-CPF groups. Since the pharmacokinetics of the individual metabolites were not modified by co-exposure to CPF; it suggests that environmental exposure to low dose mixtures of pesticides and metabolites will not impact their pharmacokinetics.

  18. Biomarkers for the assessment of chlorpyrifos effects on earthworms and on soil functional parameters Biomarcadores para a avaliação dos efeitos de clorpirifós em minhocas e em parâmetros funcionais do solo

    OpenAIRE

    Lucas Piola; Julio Fuchs; María Luisa Oneto; Silvana Basack; Rosana Giménez; Rubén Massaro; Juan Carlos Papa; Eva Kesten; Norma Casabé

    2009-01-01

    The objective of this work was to evaluate the effects of chlorpyrifos on earthworms and on soil functional parameters. An integrated laboratory-field study was performed in a wheat field in Argentina, sprayed with chlorpyrifos at two recommended application rates (240 or 960 g ha-1 style='vertical-align:baseline'> a.i.). Laboratory tests included neutral red retention time, comet assay (single cell gel electrophoresis), and avoidance behavior, each using the earthworm Eisenia andrei exposed ...

  19. Exposure to Organophosphates Reduces the Expression of Neurotrophic Factors in Neonatal Rat Brain Regions: Similarities and Differences in the Effects of Chlorpyrifos and Diazinon on the Fibroblast Growth Factor Superfamily

    OpenAIRE

    Slotkin, Theodore A.; Seidler, Frederic J; Fumagalli, Fabio

    2007-01-01

    Background The fibroblast growth factor (FGF) superfamily of neurotrophic factors plays critical roles in neural cell development, brain assembly, and recovery from neuronal injury. Objectives We administered two organophosphate pesticides, chlorpyrifos and diazinon, to neonatal rats on postnatal days 1–4, using doses below the threshold for systemic toxicity or growth impairment, and spanning the threshold for barely detectable cholinesterase inhibition: 1 mg/kg/day chlorpyrifos and 1 or 2 m...

  20. Inhibition of fipronil and nonane metabolism in human liver microsomes and human cytochrome P450 isoforms by chlorpyrifos.

    Science.gov (United States)

    Joo, Hyun; Choi, Kyoungju; Rose, Randy L; Hodgson, Ernest

    2007-01-01

    Previous studies have established that chlorpyrifos (CPS), fipronil, and nonane can all be metabolized by human liver microsomes (HLM) and a number of cytochrome P450 (CYP) isoforms. However, metabolic interactions between these three substrates have not been described. In this study the effect of either coincubation or preincubation of CPS with HLM or CYP isoforms with either fipronil or nonane as substrate was investigated. In both co- and preincubation experiments, CPS significantly inhibited the metabolism of fipronil or nonane by HLM although CPS inhibited the metabolism of fipronil more effectively than that of nonane. CPS significantly inhibited the metabolism of fipronil by CYP3A4 as well as the metabolism of nonane by CYP2B6. In both cases, preincubation with CPS caused greater inhibition than coincubation, suggesting that the inhibition is mechanism based.

  1. Acute high dose of chlorpyrifos alters performance of rats in the elevated plus-maze and the elevated T-maze.

    Science.gov (United States)

    López-Crespo, G A; Flores, P; Sánchez-Santed, F; Sánchez-Amate, M C

    2009-11-01

    Chlorpyrifos (CPF) is a broad spectrum organophosphate (OP) pesticide widely used in agriculture, industry and household. Several animal studies indicate emotional disturbances after CPF exposure, although the results are sometimes puzzling. Thus, both anxiolytic and anxiogenic effects of CPF have been reported in different animal models of anxiety [Sánchez-Amate MC, Flores P, Sánchez-Santed F. Effects of chlorpyrifos in the plus-maze model of anxiety. Behav Pharmacol 2001;12:285-92; Sánchez-Amate MC, Dávila E, Cañadas F, Flores P, Sánchez-Santed F. Chlorpyrifos shares stimulus properties with pentilenetetrazol as evaluated by and operant drug discrimination task. Neurotoxicology 2002;23:795-803; López-Crespo G, Carvajal F, Flores P, Sánchez-Santed F, Sánchez-Amate MC. Time-course of biochemical and behavioural effects of a single high dose of chlorpyrifos. Neurotoxicology 2007;28:541-7]. On the other hand, other behavioural effects of CPF are time-dependent [López-Crespo G, Carvajal F, Flores P, Sánchez-Santed F, Sánchez-Amate MC. Time-course of biochemical and behavioural effects of a single high dose of chlorpyrifos. Neurotoxicology 2007;28:541-7], raising the question that the effects of CPF could be task and post-administration time dependent. To test this hypothesis, three groups of rats were treated with a single high dose of CPF (250 mg/kg); one of the groups was tested on day 5 on the elevated plus-maze, to complete our previous study on day 2 [Sánchez-Amate MC, Flores P, Sánchez-Santed F. Effects of chlorpyrifos in the plus-maze model of anxiety. Behav Pharmacol 2001;12:285-92]. The remaining groups were tested on the elevated T-maze on days 2 and 5. CPF produced an increased open arm activity on the elevated plus-maze on day 5, an increased escape latency on the elevated T-maze on day 2 and an impaired inhibitory avoidance on day 5. Data are discussed taking together all studies carried out in our laboratory, confirming that CPF effects on

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-06-23

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

  3. Correlating Agricultural Use of Organophosphates with Outdoor Air Concentrations: A Particular Concern for Children

    OpenAIRE

    Harnly, Martha; McLaughlin, Robert; Bradman, Asa; Anderson, Meredith; Gunier, Robert

    2005-01-01

    For the organophosphate pesticide chlorpyrifos, median inhalation noncancer, acute children’s exposures in agricultural communities are elevated above reference doses; for diazinon, similar exposures are nearly elevated. We used multivariate linear regression analysis to examine the temporal and spatial associations between agricultural use and measured air concentrations of chlorpyrifos, chlorpyrifos oxon, diazinon, and malathion. Agricultural use within a 3-mile radius on the monitoring day...

  4. Effects of chlorpyrifos on the growth and reproduction of earthworms,Eisenia foetida%毒死蜱对蚯蚓生长和繁殖的影响

    Institute of Scientific and Technical Information of China (English)

    程燕; 姜锦林; 卜元卿; 周军英; 单正军

    2015-01-01

    为探明毒死蜱对蚯蚓的影响,以赤子爱胜蚓Eisenia foetida为受试生物,以人工土壤为试验基质,采用接触暴露法,研究了毒死蜱对赤子爱胜蚓的急性毒性以及对蚯蚓生长和繁殖的影响。结果表明:在有效试验条件下,毒死蜱对蚯蚓的14 d-LC50值为88.75 mg/kg(每千克干土中含毒死蜱有效成分毫克数,其余同);暴露28 d后,10、25、50、80及100 mg/kg处理组蚯蚓的平均体重与对照相比依次下降了9.8%、15.7%、17.5%、23.9%和27.0%,体重下降与药剂处理浓度之间高度相关,且除10 mg/kg处理组外均与对照差异显著( P ﹤0.01,r =0.984);毒死蜱10、25、50、80及100 mg/kg处理组对蚯蚓繁殖的抑制率分别为32.26%、80.97%、89.03%、89.68%和97.42%,繁殖抑制率与药剂浓度之间存在一定的相关性( P﹥0.01,r=0.788);毒死蜱影响蚯蚓生长和繁殖的28 d最低可观测效应浓度( LOEC)值为25 mg/kg。%In order to explore the effects of chlorpyrifos on earthworms, the acute toxicity of chlorpyrifos to Eisenia foetida and the effects of chlorpyrifos on the growth and reproduction of earthworms were investigated by exposing E. foetida to chlorpyrifos in artificial soil. The results indicated that the 14 d-LC50 value of chlorpyrifos to E. foetida was 88. 75 mg a. i. /kg dry soil;After exposure to chlorpyrifos at 10,25,50,80 and 100 mg a. i. /kg dry soil for 28 d,the weight of E. foetida reduced significantly except the treatment of 10 mg a. i. /kg dry soil;the body weight reducing rates were 9. 8%,15. 7%,17. 5%,23. 9% and 27. 0%,respectively,demonstrating a high correlation between the body weight reducing rate and the concentration( P﹤0 . 01 ,r=0 . 984 ). The reproduction inhibition rates of chlorpyrifos E. foetida at 10,25,50,80 and 100 mg/kg dry soil were 32. 26%,80. 97%,89. 03%,89. 68% and 97. 42%,respectively,indicating a certain correlation (P﹥0

  5. An Analysis of Environmental and Biological Effects of Chlorpyrifos%毒死蜱的环境生物学效应分析

    Institute of Scientific and Technical Information of China (English)

    余凯敏; 冯为民; 李国超; 张家禹; 刘丽丽; 闫艳春

    2015-01-01

    With the prohibition of high-toxicity organophosphorous pesticides, the chlorpyrifos as their substitute has been used in a large-scale. The residue of chlorpyrifos, degrading slowly in the water, may cause the potential damages to aquatic organisms and others. To investigate the endocrine disrupting effects of low-concentration chlorpyrifos, flow cytometry was used to analyze the growth cycle of endometrial cancer cell HEC-1B of human. Moreover, zebrafish embryos were selected for chlorpyrifos exposing treatment 60 h at various concentrations of 0, 1.0, 2.0, 3.0 and 4.0 ppm. It was found that the chlorpyrifos caused the zebrafish embryos to death and significant embryonic malformation, the survival rate of the embryos was inversely proportional to chlorpyrifos’ concentration, and the malformation rate was proportional to chlorpyrifos’ concentration. Further, the mRNA expression levels of 5 neurodevelopment maker genes in the chlorpyrifos-treated zebrafish embryos were detected. These results showed that chlorpyrifos of low-concentration acted as endocrine disruptor, and chlorpyrifos of high-concentration affected the normal development of nerve system.%高毒有机磷农药禁用以后,毒死蜱作为其替代品逐渐开始大规模应用。毒死蜱在水中降解缓慢,因此在水中的残留会对水生生物及其他生物造成潜在危害。为探究低浓度毒死蜱的内分泌干扰效应,使用流式细胞仪分析了其对人子宫内膜癌细胞HEC-1B生长周期的影响。为探究高浓度毒死蜱的生物毒性,将斑马鱼胚胎暴露在不同浓度的毒死蜱(0、1.0、2.0、3.0和4.0 ppm)中60 h,发现毒死蜱能导致斑马鱼胚胎的死亡和严重畸形,并且胚胎存活率与处理浓度呈负相关,畸形率与处理浓度呈正相关。最后,检测了毒死蜱处理后斑马鱼胚胎中5种神经系统发育相关基因的表达情况。结果表明,低浓度毒死蜱具有内分泌干扰效应,高浓

  6. The Organophosphate Chlorpyrifos Interferes with the Responses to 17β-Estradiol in the Digestive Gland of the Marine Mussel Mytilus galloprovincialis

    OpenAIRE

    Laura Canesi; Alessandro Negri; Cristina Barmo; Mohamed Banni; Gabriella Gallo; Aldo Viarengo; Francesco Dondero

    2011-01-01

    BACKGROUND: Many pesticides have been shown to act as endocrine disrupters. Although the potencies of currently used pesticides as hormone agonists/antagonists are low compared with those of natural ligands, their ability to act via multiple mechanisms might enhance the biological effect. The organophosphate Chlorpyrifos (CHP) has been shown to be weakly estrogenic and cause adverse neurodevelopmental effects in mammals. However, no information is available on the endocrine effects of CHP in ...

  7. Fitness effects of chlorpyrifos in the damselfly Enallagma cyathigerum strongly depend upon temperature, food level and the fitness-related variable

    OpenAIRE

    Janssens, Lizanne; Stoks, Robby

    2013-01-01

    Interactions between pollutants and suboptimal environmental conditions can have severe consequences for the toxicity of pollutants, yet are still poorly understood. To identify patterns across environmental conditions and across fitness-related variables we exposed Enallagma cyathigerum damselfly larvae to the pesticide chlorpyrifos at two food levels or at two temperatures and quantified four fitness-related variables (larval survival, development time, mass at emergence and adult cold resi...

  8. A non-target chemometric strategy applied to UPLC-MS sphingolipid analysis of a cell line exposed to chlorpyrifos pesticide: a feasibility study

    OpenAIRE

    Kássio M. G. Lima; Bedia, Carmen; Tauler, Romá

    2014-01-01

    A non-target chemometrics study based on the application of Multivariate Curve Resolution Alternating Least Squares (MCR-ALS) method to a data set obtained by ultra-performance liquid chromatographic coupled to mass spectrometry (UPLC-MS) has been applied to the study of human prostate cancer (DU145) cell line samples treated with the organophosphate pesticide chlorpyrifos (CPF). Full scan UPLC-MS data sets were segmented in 17 different chromatographic windows and submitted to a non-target d...

  9. Does the home environment and the sex of the child modify the adverse effects of prenatal exposure to chlorpyrifos on child working memory?

    OpenAIRE

    Horton, Megan K; Kahn, Linda G.; Perera, Frederica; Barr, Dana Boyd; Rauh, Virginia

    2012-01-01

    Prenatal exposure to chlorpyrifos (CPF), an organophosphorus insecticide, has long been associated with delayed neurocognitive development and most recently with decrements in working memory at age 7. In the current paper, we expanded the previous work on CPF to investigate how additional biological and social environmental factors might create or explain differential neurodevelopmental susceptibility, focusing on main and moderating effects of the quality of the home environment (HOME) and c...

  10. Influence of the pesticides glyphosate, chlorpyrifos and atrazine on growth parameters of nonochratoxigenic Aspergillus section Nigri strains isolated from agricultural soils.

    Science.gov (United States)

    Carranza, Cecilia S; Barberis, Carla L; Chiacchiera, Stella M; Magnoli, Carina E

    2014-01-01

    This investigation was undertake to determine the effect of glyphosate, chlorpyrifos and atrazine on the lag phase and growth rate of nonochratoxigenic A. niger aggregate strains growing on soil extract medium at -0.70, -2.78 and -7.06 MPa. Under certain conditions, the glyphosate concentrations used significantly increased micelial growth as compared to control. An increase of about 30% was observed for strain AN 251 using 5 and 20 mg L(-1) of glyphosate at -2.78 MPa. The strains behaved differently in the presence of the insecticide chlorpyrifos. A significant decrease in growth rate, compared to control, was observed for all strains except AN 251 at -2.78 MPa with 5 mg L(-1). This strain showed a significant increase in growth rate. With regard to atrazine, significant differences were observed only under some conditions compared to control. An increase in growth rate was observed for strain AN 251 at -2.78 MPa with 5 and 10 mg L(-1) of atrazine. By comparison, a reduction of 25% in growth rate was observed at -7.06 MPa and higher atrazine concentrations. This study shows that glyphosate, chlorpyrifos and atrazine affect the growth parameters of nonochratoxigenic A. niger aggregate strains under in vitro conditions.

  11. Behavioral and metabolic effects of sublethal doses of two insecticides, chlorpyrifos and methomyl, in the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Dewer, Youssef; Pottier, Marie-Anne; Lalouette, Lisa; Maria, Annick; Dacher, Matthieu; Belzunces, Luc P; Kairo, Guillaume; Renault, David; Maibeche, Martine; Siaussat, David

    2016-02-01

    Insecticides have long been used as the main method in limiting agricultural pests, but their widespread use has resulted in environmental pollution, development of resistances, and biodiversity reduction. The effects of insecticides at low residual doses on both the targeted crop pest species and beneficial insects have become a major concern. In particular, these low doses can induce unexpected positive (hormetic) effects on pest insects, such as surges in population growth exceeding what would have been observed without pesticide application. Methomyl and chlorpyrifos are two insecticides commonly used to control the population levels of the cotton leafworm Spodoptera littoralis, a major pest moth. The aim of the present study was to examine the effects of sublethal doses of these two pesticides, known to present a residual activity and persistence in the environment, on the moth physiology. Using a metabolomic approach, we showed that sublethal doses of methomyl and chlorpyrifos have a systemic effect on the treated insects. We also demonstrated a behavioral disruption of S. littoralis larvae exposed to sublethal doses of methomyl, whereas no effects were observed for the same doses of chlorpyrifos. Interestingly, we highlighted that sublethal doses of both pesticides did not induce a change in acetylcholinesterase activity in head of exposed larvae.

  12. Sublethal effects of diazinon, fenitrothion and chlorpyrifos on the functional response of predatory bug, Andrallus spinidens Fabricius (Hem.: Pentatomidae in the laboratory conditions

    Directory of Open Access Journals (Sweden)

    Moloud GholamzadehChitgar

    2014-04-01

    Full Text Available The sublethal effects of diazinon, fenitrothion and chlorpyrifos on the functional response of predatory bug, Andrallus spinidens Fabricius (Hem.: Pentatomidae, a potential biological control agent, were studied on 5th-instar nymphs. The experiment was conducted in varying densities (2, 4, 8, 16, 32 and 64 of last instars larvae of Chilo suppressalis Walker (Lepidoptera: Pyralidae as prey at 25 ± 2 °C, 60% ± 10% relative humidity (RH and a photoperiod of 16:8 h (L: D. The results of logistic regressions revealed a type II functional response in the control and all insecticide treatments. Comparison of functional response curves revealed that tested insecticides markedly decreased the mean of preys consumed by A. spinidens. Among them, functional response curve of A. spinidens in chlorpyrifos treatment was significantly lower than the other treatments. In this study, application of insecticides caused a decrease in the attack rate and an increase in the handling time of exposed bugs compared with the control. The longest handling time (3.97 ± 0.62 and the lowest attack rate (0.023 ± 0.007 were observed in chlorpyrifos and fenitrothion treatments, respectively. The results suggested that the adverse effect of these insecticides on A. spinidens should be considered in integrated pest management programs (IPM.

  13. Identification of multi-insecticide residues using GC-NPD and the degradation kinetics of chlorpyrifos in sweet corn and soils.

    Science.gov (United States)

    Wang, Peidan; Rashid, Muhammad; Liu, Jie; Hu, Meiying; Zhong, Guohua

    2016-12-01

    Because more than one insecticide is applied to crops to protect plants from pests, an analytical multi-residue determination method was developed using gas chromatography with a nitrogen phosphorus detector (GC-NPD). The retention time for 12 insecticides was 3.7-27.7min. Under the selected conditions, the limits of detection (LOD) and quantification (LOQ) were below the maximum residue limits (MRLs) and in the range of 0.00315-0.05μgmL(-1) and 0.01-0.165μgmL(-1), respectively. Using GC-NPD, we investigated the dissipation dynamics and final residual levels of chlorpyrifos in sweet corn and soil and determined that the half-lives was 4-7days, that is, that chlorpyrifos is safe to use on sweet corn with a pre-harvest interval of 16-22days before harvest. These results provide new insights into chlorpyrifos degradation in plants and its environmental behavior. PMID:27374551

  14. 毒死蜱对尖膀胱螺的急性毒性试验%Acute Toxicity of Chlorpyrifos to Physa acuta

    Institute of Scientific and Technical Information of China (English)

    马军国; 李效宇

    2012-01-01

    选取尖膀胱螺(Physa acuta)作为试验材料,研究了毒死蜱对尖膀胱螺的急性毒性作用.结果表明,随着毒死蜱浓度的升高和处理时间的延长,各浓度组尖膀胱螺的平均死亡率均升高,呈明显的剂量效应和时间效应.毒死蜱对尖膀胱螺的24、48、72、96 h的LC50分别为0.577、0.308、0.243、0.160 mg/L,安全浓度为0.016 mg/L.试验结果显示,尖膀胱螺对毒死蜱非常敏感,含微量毒死蜱的水体都会对尖膀胱螺的生存产生危害.因此,尖膀胱螺可作为水环境毒理学研究的实验动物模型.%Physa acuta was chosen as the experiment material. The acute toxicity of chlorpyrifos to Physa acuta was investigated. The results showed that the average mortality rate was increased for each set of P. Acuta as the concentration of chlorpyrifos and treatment time increased, and showed the significant dose effect and time effect. The 24, 48, 72 and 96 h LC50 of chlorpyrifos for P. Acuta were 0.577, 0.308, 0.243 and 0.160 mg/L, respectively. The safe concentration was 0.016 mg/L. The results also revealed that P. Acuta was very sensitive to chlorpyrifos, thus, traces of chlorpyrifos in water would be harmful to the survival of P. Acuta. P. Acuta should be good experimental model organism for the water environmental toxicology research.

  15. Biodegradation of Chlorpyrifos by Manganese Peroxidase%锰过氧化物酶(MnP)对农药毒死蜱降解的初步研究

    Institute of Scientific and Technical Information of China (English)

    莫彩萍; 赵林果; 谢慧芳

    2012-01-01

    Biodegradation of chlorpyrifos by manganese peroxidase (MnP) which was prepared using whit rot fungi P. sordida YK-624 was studied. The systems of chlorpytifos biodegradation were tested. Results showed that the chlorpyrifos biodegradation by MnP should be done in organic acid buffer solution (malonic acid)containing Mn2+ and H2O2 which was produced by glucose oxidase oxidizing glucose. But surfactant Tween 80 was not necessary because of poor solubility of chlorpyrifos. Main influencing factors were determined. It proved that chlorpyrifos could be biodegraded by MnP at 30 ℃ in pH 4.5 malonic acid buffer system, which contained 7.5 mmmol/L MnSO4,2.5 mmol/L glucose and 40 U glucose oxidase. Under the conditions, 400 U/L MnP could degrade 77.51% 30 mg/L chlorpyrifos. GC-MS was used to analyze the product of chlorpyrifos biodegradation by MnP. It was found the possible enzymolysis product was O, O, O', O'-tetraethyl-dithiopyrophosphate, different from hydrolysis or bacterium degradation production of chlorpyrifos.%以广泛使用的有机磷杀虫剂毒死蜱为研究对象,利用白腐菌P.sordida YK-624.菌株所产锰过氧化物酶(MnP)对其进行生物降解的初步研究.首先比较确定了MnP降解毒死蜱所需要的降解体系,即对于毒死蜱的降解,需要在有机酸(丙二酸)存在的缓冲体系中进行,此体系不需要表面活性剂Tween 80,但必须含有Mn2+和葡萄糖氧化酶氧化葡萄糖产生的H2O2.随后对主要影响因素的试验结果表明,MnP降解毒死蜱较好的条件是在pH 4.5的丙二酸缓冲体系中含7.5 mmol/L MnSO4、2.5 mmol/L葡萄糖以及40 U葡萄糖氧化酶,温度30℃.此时,400 U/L的MnP可将30 mg/L的毒死蜱经3d时间降解77.51%.同时,利用GC-MS对毒死蜱酶降解后的产物进行了初步分析,得到1种可能的酶解产物O,O,O’,O’-四乙基二硫代焦磷酸酯,不同于水解和细菌降解途径,值得进行进一步研究.

  16. Effect of atrazine and chlorpyrifos on common carp's liver%毒死蜱和阿特拉津对鲤肝脏的影响

    Institute of Scientific and Technical Information of China (English)

    韩英; 郝其睿; 魏菁; 赵荣伟; 牟振波; 徐革锋; 刘洋

    2015-01-01

    探讨阿特拉津(Atrazine,ATR)、毒死蜱(Chlorpyrifos,CPF)及其混合物对鲤(Cyprinus carpio L.)肝脏和血液相关指标的影响。将实验鲤分别暴露于不同浓度的阿特拉津、毒死蜱及其混合物中,并分别于175、350和525 d采集其肝组织、血液等样品。结果表明,阿特拉津和毒死蜱在鲤肝组织中均有残留,残留量随暴露时间及浓度的增加而降低;与对照组比较,各染毒组碱性磷酸酶、谷丙转氨酶及血糖水平显著升高,总蛋白、白蛋白水平下降,抗氧化能力下降,且毒死蜱与阿特拉津混合后毒性作用更强,说明两者的毒性有叠加作用;染毒后,肝脏ER-α和VTG-II基因表达水平升高。结果显示,鲤肝脏对阿特拉津和毒死蜱有较强的代谢能力,阿特拉津和毒死蜱在鲤肝脏无富集作用;阿特拉津和毒死蜱使鲤肝功能受损,抗氧化能力降低;ER-α和VTG-II基因的高调表达显示出阿特拉津和毒死蜱对鲤亦有环境雌激素作用。%In this study our purpose is to discuss the effects of atrazine and chlorpyrifos and their mixture to related index of common carp's liver and blood. Exposeed experimental carps respectively in atrazine, chlorpyrifos and their mixture of different concentrations, and collected samples of common carp's liver and blood at 175, 350 and 525 d. Results showed that both atrazine and chlorpyrifos had re-sidual in common carp's liver and the residual quantity reduced with the exposure time and the concen-tration increasing. Compared to the control group, the alkaline phosphatase, glutamic-pyruvic transami-nase and blood glucose levels of each infected group had significant rise, while the total protein and al-bumin levels declined. Moreover, the toxicity of the mixture of atrazine and chlorpyrifos was stronger than that prior to the blending, which illustrated the toxicity of the two have superposition. After infected, the expression

  17. 土壤环境因子对毒死蜱两种剂型持效性的影响%Influence of environmental factors on persistence of chlorpyrifos microcapsule suspension and emulsifiable concentrate in soils

    Institute of Scientific and Technical Information of China (English)

    季静; 李杨; 高志山; 刘峰

    2011-01-01

    Influence of environmental factors on persistence of chlorpyrifos microcapsule suspension ( CS) and emulsifiable concentrate (EC) against larva of Holotrichia parallela in soils were studied under ambient conditions using bioassay method. The results indicated that under the same conditions, persistence of chlorpyrifos EC decreased and the release of chlorpyrifos in microcapsules slowed down as soil moisture increased. Persistence of chlorpyrifos CS and EC in soil decreased as soil temperature increased. The active ingredient was trapped by organic soil, so the toxicity of chlorpyrifos CS and EC against H. Parallela decreased, however its persistence extended. Among the results of different environmental factors tested, the persistence of chlorpyrifos CS in soil were all better than that of chlorpyrifos EC except when the organic content in soil was 1.0% , which showed that the persistence of chlorpyrifos CS and chlorpyrifos EC was similar.%以暗黑鳃金龟Holotrichia parallela幼虫为生物试材,研究了含水量、温度和泥炭质量分数3种土壤环境因子对毒死蜱30%微囊悬浮剂(CS)和30%乳油(EC)持效性的影响.结果显示:在相同土壤介质环境下,毒死蜱乳油的持效期随土壤含水量的提高而缩短,同时土壤含水量的提高减缓了微囊悬浮剂囊内有效成分的释放;在土壤中其他影响因子相同时,土壤温度越高,毒死蜱微囊悬浮剂和乳油的持效期越短;土壤中的泥炭对毒死蜱的吸附作用使得其对暗黑鳃金龟幼虫的初始毒力降低,同时也延长了毒死蜱在土壤中的持效期.对于3种土壤环境因子的不同处理,除泥炭质量分数为1.0%的处理中毒死蜱微囊悬浮剂和乳油对暗黑鳃金龟幼虫的持效性相差不大外,其他各处理中毒死蜱微囊悬浮剂的持效性均优于乳油.

  18. Biodegradation of chlorpyrifos by Klebsiella sp. isolated from an activated sludge sample of waste water treatment plant in Damascus.

    Science.gov (United States)

    Ghanem, I; Orfi, M; Shamma, M

    2007-01-01

    A chlorpyrifos (CPY)-degrading bacterial strain was isolated from an activated sludge sample collected from the Damascus Wastewater Treatment Plant, Syria. The isolation of Klebsiella sp. was facilitated by the addition of CPY at a rate of 3.84 g/L of sludge weekly (selection pressure). Identification of Klebsiella sp. was done using major staining and biochemical differentiation tests (Gram stain, cytochrome oxidase and some relevant saccharide fermentation tests using biochemical assays). Klebsiella sp. was maintained by culturing in a poor medium consisting of mineral salts and CPY as the sole carbon source. When 3 activated sludge samples were incubated in the presence of CPY (13.9 g/L sludge), 46% of added CPY were degraded within 4 d. By comparison, within 4 d the isolated Klebsiella sp. was found to break down 92% of CPY when co-incubated in a poor mineral medium in which CPY was the sole carbon source (13.9 g/L poor medium). Isolated Klebsiella sp. was able to tolerate up to 17.3 g of CPY in the poor medium. PMID:18062192

  19. Evaluation of chronic chlorpyrifos-induced reproductive toxicity in male Wistar rat: protective effects of vitamin C

    Directory of Open Access Journals (Sweden)

    Mohammed M. Sulaiman

    2013-02-01

    Full Text Available The aim of the present study was to evaluate the effect of vitamin C on reproductive toxicity, induced by chronic chlorpyrifos (CPF exposure in male Wistar rats. Twenty adult male Wistar rats were divided into 4 groups of 5 animals in each group. Group I received soya oil (2 ml/kg; group II was given vitamin C only (100 mg/kg; group III was administered CPF only (10.6 mg/kg; ~1/8th LD50, while group IV was pretreated with vitamin C and then exposed to CPF, 30 min later. The regimens were administered by gavage once daily for 15 weeks. At the end of the treatment period, the animals were sacrificed by jugular venesection after light chloroform anesthesia, and sera obtained from the blood samples were analyzed for follicle-stimulating hormone (FSH, luteinizing hormone (LH and testosterone concentrations. Pituitary gland and the testicular tissues of each rat were quickly dissected, removed and assayed for the levels of glycogen and acetylcholinesterase (AChE activity. The right caudal epididymis was evaluated for spermatozoa concentrations. The results showed that decrease in concentrations of spermatozoa, luteinizing and follicle-stimulating hormones, testosterone, testicular glycogen, and inhibition of pituitary gland and testicular AChE activities caused by CPF were ameliorated by vitamin C. [J Exp Integr Med 2013; 3(1: 23-30

  20. Effectiveness of the compound chlorpyrifos+ cypermethrin+citronellal against Alphitobius diaperinus: laboratory analysis and residue determination in carcasses

    Directory of Open Access Journals (Sweden)

    GS Silva

    2007-09-01

    Full Text Available Effectiveness, biological security and the absence of residues in meat and/or eggs must be considered when recommending options for the control Alphitobius diaperinus in poultry production environments. This research study evaluated the effectiveness of cypermethrin+ chlorpyrifos+citronellal in the control of A. diaperinus, including analysis for the presence of residues of this compound in poultry carcasses (experimental farm. Two studies were carried out under laboratory conditions. One used paper filters a four dilutions of the compound, and the other used a container including with pulverized broiler litter and the compound. The analysis of carcasses for residues was conducted in broilers that raised in a broiler house treated (floor and/or litter with the compound at a dilution of 1:800. Birds were regularly sacrificed, submitted to necropsy, and liver, muscle and fat fragments were collected. Gas chromatography was used to identify the possible presence of any chemical residue in these samples. High effectiveness rates against A.diaperinus were observed in the two laboratory studies, as well as the absence of residues in the carcasses. This compound, used in the studied concentrations, can be recommended as a valuable alternative for the control and treatment of A. diaperinus.

  1. Gas-phase and particulate products from the atmospheric degradation of the organothiophosphorus insecticide chlorpyrifos-methyl.

    Science.gov (United States)

    Borrás, Esther; Tortajada-Genaro, Luis Antonio; Ródenas, Milagros; Vera, Teresa; Coscollá, Clara; Yusá, Vicent; Muñoz, Amalia

    2015-11-01

    The phosphorothioate structure is highly present in several organophosphorus pesticides. However, there is insufficient information about its degradation process after the release to the atmosphere and the secondary pollutants formed. Herein, the atmospheric reaction of chlorpyrifos-methyl (o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate), is described for semi-urban or rural locations. The photo-oxidation under low NOx conditions (5-55 ppbV) was reproduced in a large outdoor simulation chamber, observing a rapid degradation (lifetime<3.5 h). The formation of gaseous products and particulate matter (aerosol yield 2-8%) was monitored. The chemical composition of minor products (gaseous and particulate) was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate, dimethyl 3,5,6-trichloropyridin-2-yl phosphate, o-methyl o-(3,5,6-trichloropyridin-2-yl) hydrogen phosphorothioate, 3,5,6-trichloropyridin-2-yl dihydrogen phosphate, 3,5,6-trichloropyridin-2-ol, and 3,5,6-trichloropyridine-2,4-diol. An atmospheric degradation mechanism has been proposed based on an oxidation started with OH-nucleophilic attack to P=S bond. The results have been extrapolated to other organothiophosphorus molecules, such as malathion, parathion, diazinon and methidathion, among many others, to estimate their photo-oxidative degradation and the expected products. PMID:25548033

  2. Chlorpyrifos Induces the Expression of the Epstein-Barr Virus Lytic Cycle Activator BZLF-1 via Reactive Oxygen Species

    Directory of Open Access Journals (Sweden)

    Ling Zhao

    2015-01-01

    Full Text Available Organophosphate pesticides (OPs are among the most widely used synthetic chemicals for the control of a wide variety of pests, and reactive oxygen species (ROS caused by OPs may be involved in the toxicity of various pesticides. Previous studies have demonstrated that a reactivation of latent Epstein-Barr virus (EBV could be induced by oxidative stress. In this study, we investigated whether OPs could reactivate EBV through ROS accumulation. The Raji cells were treated with chlorpyrifos (CPF, one of the most commonly used OPs. Oxidative stress indicators and the expression of the EBV immediate-early gene BZLF-1 were determined after CPF treatment. Our results show that CPF induces oxidative stress as evidenced by decreased malondialdehyde (MDA level, accompanied by an increase in ROS production, DNA damage, glutathione (GSH level, and superoxide dismutase (SOD and catalase (CAT activity. Moreover, CPF treatment significantly enhances the expression of BZLF-1, and the increased BZLF-1 expression was ameliorated by N-acetylcysteine (NAC incubation. These results suggest that OPs could contribute to the reactivation of the EBV lytic cycle through ROS induction, a process that may play an important role in the development of EBV-associated diseases.

  3. Role of freeze-thaw cycles and chlorpyrifos insecticide use on diffuse Cd loss and sediment accumulation.

    Science.gov (United States)

    Wang, Fangli; Ouyang, Wei; Hao, Fanghua; Jiao, Wei; Shan, Yushu; Lin, Chunye

    2016-06-02

    Freeze-thaw cycles are predicted to increase in cold temperate regions. The potential influence of the interactions of freeze-thaw cycles and agrochemicals on the release of Cd into river water is unknown. In this study, the interactions of freeze-thaw cycles and chlorpyrifos (FC) on Cd mobility in soils were analysed. The spatial variability of soil Cd under long-term intensive tillage in a freeze-thaw agro-system was also identified. The temporal variation of sediment Cd was detected based on analysis of the sediment geochemistry. The results showed that FC increased soil Cd mobility, with an increase of approximately 10% in CaCl2-extractable Cd. The increased mobile fractions of water-soluble and exchangeable Cd originated from the decreased fraction of Fe-Mn-oxide-associated Cd and organic matter-bound Cd. The total Cd content in the surface soil followed the zonally decreasing trend of dry land > paddy land > natural land. The Cd concentrations and sedimentation rates of the sediment core generally increased from 1943 to 2013 due to agricultural exploration and farmland irrigation system construction, indicating an increase of the Cd input flux into water. The results provide valuable information about the soil Cd transport response to the influence of climatic and anthropogenic factors in cold intensive agro-systems.

  4. Chlorpyrifos-methyl solubilisation by humic acids used as bio-surfactants extracted from lignocelluloses and kitchen wastes.

    Science.gov (United States)

    Scaglia, Barbara; Baglieri, Andrea; Tambone, Fulvia; Gennari, Mara; Adani, Fabrizio

    2016-09-01

    Chlorpyrifos-methyl (CLP-m) is a widely used organophosphate insecticide that can accumulate in soil and become toxic to humans. CLP-m can be removed from soil by its solubilisation using synthetic surfactants. However, synthetic surfactants can accumulate in soil causing contamination phenomena themselves. Bio-surfactants can be used as an alternative to synthetic ones, reducing costs and environmental issues. In this work, humic acid (HA) extracted from raw biomasses, i.e. lignocelluloses (HAL) and lignocelluloses plus kitchen food waste (HALF), corresponding composts (C) (HALC and HALFC) and leonardite (HAc), were tested in comparison with commercial surfactants, i.e. SDS, Tween 20 and DHAB, to solubilize CLP-m. Results obtained indicated that only biomass-derived HA, composted biomass-derived HA, and SDS solubilized CLP-m: SDS = 0.006; HAL = 0.007; HALC = 0.009 g; HALF = 0.025; HALFC = 0.024) (g CLP-m g(-1) surfactant). Lignocelluloses HAs (HAL, HALF) solubilized CLP-m just as well as SDS while lignocellulosic plus kitchen food waste HA (HALF, HALFC) showed a three times higher CLP-m solubilisation capability. This difference was attributed to the higher concentration of alkyl-Carbon that creates strong links with CLP-m in the hydrophobic micelle-core of the surfactants. PMID:27289207

  5. Role of freeze-thaw cycles and chlorpyrifos insecticide use on diffuse Cd loss and sediment accumulation

    Science.gov (United States)

    Wang, Fangli; Ouyang, Wei; Hao, Fanghua; Jiao, Wei; Shan, Yushu; Lin, Chunye

    2016-06-01

    Freeze-thaw cycles are predicted to increase in cold temperate regions. The potential influence of the interactions of freeze-thaw cycles and agrochemicals on the release of Cd into river water is unknown. In this study, the interactions of freeze-thaw cycles and chlorpyrifos (FC) on Cd mobility in soils were analysed. The spatial variability of soil Cd under long-term intensive tillage in a freeze-thaw agro-system was also identified. The temporal variation of sediment Cd was detected based on analysis of the sediment geochemistry. The results showed that FC increased soil Cd mobility, with an increase of approximately 10% in CaCl2-extractable Cd. The increased mobile fractions of water-soluble and exchangeable Cd originated from the decreased fraction of Fe-Mn-oxide-associated Cd and organic matter-bound Cd. The total Cd content in the surface soil followed the zonally decreasing trend of dry land > paddy land > natural land. The Cd concentrations and sedimentation rates of the sediment core generally increased from 1943 to 2013 due to agricultural exploration and farmland irrigation system construction, indicating an increase of the Cd input flux into water. The results provide valuable information about the soil Cd transport response to the influence of climatic and anthropogenic factors in cold intensive agro-systems.

  6. A statistical assessment of pesticide pollution in surface waters using environmental monitoring data: Chlorpyrifos in Central Valley, California.

    Science.gov (United States)

    Wang, Dan; Singhasemanon, Nan; Goh, Kean S

    2016-11-15

    Pesticides are routinely monitored in surface waters and resultant data are analyzed to assess whether their uses will damage aquatic eco-systems. However, the utility of the monitoring data is limited because of the insufficiency in the temporal and spatial sampling coverage and the inability to detect and quantify trace concentrations. This study developed a novel assessment procedure that addresses those limitations by combining 1) statistical methods capable of extracting information from concentrations below changing detection limits, 2) statistical resampling techniques that account for uncertainties rooted in the non-detects and insufficient/irregular sampling coverage, and 3) multiple lines of evidence that improve confidence in the final conclusion. This procedure was demonstrated by an assessment on chlorpyrifos monitoring data in surface waters of California's Central Valley (2005-2013). We detected a significant downward trend in the concentrations, which cannot be observed by commonly-used statistical approaches. We assessed that the aquatic risk was low using a probabilistic method that works with non-detects and has the ability to differentiate indicator groups with varying sensitivity. In addition, we showed that the frequency of exceedance over ambient aquatic life water quality criteria was affected by pesticide use, precipitation and irrigation demand in certain periods anteceding the water sampling events.

  7. Biodegradation Characteristics of Chlorpyrifos by Mixed Culture of Bacillus cereus Strains%两株降解菌混合对毒死蜱的降解特性研究

    Institute of Scientific and Technical Information of China (English)

    段海明

    2013-01-01

    In the present work,we investigated for the first time the degradation characteristics of chlorpyrifos by the mixed culture of Bacillus cereus strains.The optimal ratio of inoculation volume of the two strains for chlor-pyrifos degradation was established .Further,the effects of the inoculation volume,glucose concentration,initial pH and the initial chlorpyrifos concentration on the degradation efficiency of chlorprifos were determined .Simultaneous-ly,the effect of high salinity on the biodegradation activity of chlorpyrifos was also examined .The results showed that when the ratio(V/V) was 1∶1,the degradation rate to 80 mg/Lof chlorpyrifos reached the highest .The optimal in-oculum amount of the mixed strains was 8%(V/V) of the total volume.Addition of glucose stimulated the growth of the mixed strains but did not enhance the degradation efficiency of chlorpyrifos .The alkaline environment was prone to form the biomass and to achieve a high degradation rate of chlorpyrifos by the mixed strains .When the initial con-centration of chlorpyrifos was 42 mg/L,the residual concentration of chlorpyrifos decreased with the time .However, the degradation curves of chlorpyrifos at high concentrations (108,126 mg/L) followed two peaks.The degradation rate of the mixed strains to 80 mg/L of chlorpyrifos was above 41%while the sodium chloride concentration ranged from 20 g/L to 70 g/L.The results suggest that the mixed strains could be used as a potential and efficient chlor -pyrifos degrader for the bioremediation of contaminated sites ,especially for the cleanup of high salinity wastewater in the chlorpyrifos production enterprises .%  为明确2株蜡状芽孢杆菌(Bacillus cereus)混合对毒死蜱的降解效果,以混合菌对毒死蜱的降解率和菌株的生长量为依据,考察了混合菌不同配比和不同环境因素对混合菌降解毒死蜱的影响。结果表明,两菌株的比例为1∶1(V/V)时,对80 mg/L毒死蜱的降解率最

  8. 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...

  9. Changes in Behavior and Brain Acetylcholinesterase Activity in Mosquito Fish, Gambusia affinis in Response to the Sub-Lethal Exposure to Chlorpyrifos

    Directory of Open Access Journals (Sweden)

    R. Nageswara Rao

    2005-12-01

    Full Text Available Sub-lethal studies of chlorpyrifos, O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl phosphorothioate on mosquito fish, Gambusia affinis were carried out in vivo, for 20 days to assess the locomotor behavior in relation to bioaccumulation and interaction with a targeted enzyme, acetylcholinesterase (AChE, EC: 3.1.1.7. Fish exposed to sub-lethal concentration of 60 Ag/L (1/5 of LC50 were under stress, and reduced their locomotor behavior like distance travelled per unit time (m/min and swimming speed (cm/sec with respect to the length of exposure. The alteration in locomotor behavior of fish may be due to an accumulation of acetylcholine (ACh, a neurotransmitter at synaptic junctions, due to the inhibition of AChE enzyme activity (40 to 55% in brain and also bioaccumulation of the toxicant in different parts of fish. The bioaccumulation values indicated that the accumulation of chlorpyrifos was maximum in viscera followed by head and body. The average bioconcentration values are 0.109, 0.009 and 0.004 Ag/g for viscera, head and body with depuration rates of 2.24, 1.69 and 0.39 ng/h respectively. It is evident from the results that the sub-lethal concentration [1/5 of LC50; equivalent to Lowest Observed Effect Concentration (LOEC] of chlorpyrifos can able to alter the locomotor behavior of G. affinis in relation to the length of exposure. The findings revealed that the locomotor activity of test organism could be considered as a suitable marker to evaluate the affect of toxicant even at LOEC levels.

  10. Control of pyrethroid and DDT-resistant Anopheles gambiae by application of indoor residual spraying or mosquito nets treated with a long-lasting organophosphate insecticide, chlorpyrifos-methyl

    Directory of Open Access Journals (Sweden)

    Chabi Joseph

    2010-02-01

    Full Text Available Abstract Background Scaling up of long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS with support from the Global Fund and President's Malaria Initiative is providing increased opportunities for malaria control in Africa. The most cost-effective and longest-lasting residual insecticide DDT is also the most environmentally persistent. Alternative residual insecticides exist, but are too short-lived or too expensive to sustain. Dow Agrosciences have developed a microencapsulated formulation (CS of the organophosphate chlorpyrifos methyl as a cost-effective, long-lasting alternative to DDT. Methods Chlorpyrifos methyl CS was tested as an IRS or ITN treatment in experimental huts in an area of Benin where Anopheles gambiae and Culex quinquefasiactus are resistant to pyrethroids, but susceptible to organophosphates. Efficacy and residual activity was compared to that of DDT and the pyrethroid lambdacyalothrin. Results IRS with chlorpyrifos methyl killed 95% of An. gambiae that entered the hut as compared to 31% with lambdacyhalothrin and 50% with DDT. Control of Cx. quinquefasciatus showed a similar trend; although the level of mortality with chlorpyrifos methyl was lower (66% it was still much higher than for DDT (14% or pyrethroid (15% treatments. Nets impregnated with lambdacyhalothrin were compromized by resistance, killing only 30% of An. gambiae and 8% of Cx. quinquefasciatus. Nets impregnated with chlorpyrifos methyl killed more (45% of An gambiae and 15% of Cx. quinquefasciatus, but its activity on netting was of short duration. Contact bioassays on the sprayed cement-sand walls over the nine months of monitoring showed no loss of activity of chlorpyrifos methyl, whereas lambdacyhalothrin and DDT lost activity within a few months of spraying. Conclusion As an IRS treatment against pyrethroid resistant mosquitoes chlorpyrifos methyl CS outperformed DDT and lambdacyhalothrin. In IRS campaigns, chlorpyrifos methyl CS should

  11. Repeated dose 28-day oral toxicity study in Wistar rats with a mixture of five pesticides often found as residues in food: alphacypermethrin, bromopropylate, carbendazim, chlorpyrifos and mancozeb

    DEFF Research Database (Denmark)

    Jacobsen, H.; Østergaard, G.; Lam, Henrik Rye;

    2004-01-01

    -6 female rats, and relative thyroid gland weight was significantly increased in groups 2-6 male rats and of groups 3-6 female rats. Absolute thymus weight of groups 3-6 male and female rats and relative thymus weight of groups 3-6 male rats and groups 3 and 4 female rats was significantly decreased. A mild...... of acetylcholinesterase activity in plasma and brain by chlorpyrifos was not enhanced by coadministration of the other four pesticides. Effects were seen in liver, thyroid, thymus and blood in the combination groups. However, identification of the pesticide(s) responsible for these changes would require further studies...

  12. Sensitivity comparison of different hybrids of silkworm to chlorpyrifos%不同家蚕品种对毒死蜱的敏感性比较

    Institute of Scientific and Technical Information of China (English)

    柳新菊; 俞瑞鲜; 赵学平; 陈诗; 蒋金花; 祝新荣

    2014-01-01

    采用食下毒叶法测定和比较了有机磷农药毒死蜱对14个不同品种家蚕的室内急性毒性,结果表明:对毒死蜱敏感性较强的家蚕品种有皓月和7532,其96h-LC50分别为1.8426和2.1452 mg・L-1;敏感性较弱的蚕品种有春晓、浙蕾、872、限2和871,其96h-LC50为2.9937~3.3471 mg・L-1;敏感性弱的蚕品种有秋实、白玉、CA、菁松、JA、芙蓉和湘晖,其96h-LC50为3.5190~4.5665 mg・L-1。说明不同品种的家蚕对农药毒死蜱的敏感性不同,其中皓月和7532对毒死蜱最为敏感。%Acute toxicities of chlorpyrifos to 14 different hybrids of silkworm (Bombyx mori) were evaluated in the laboratory using the leaf dipping method .Results showed that the 96h-LC50 of chlorpyrifos to Haoyue and 7532 were 1.8426 and 2.1452 mg・L-1 respectively.While the 96h-LC50 of chlorpyrifos to Chunxiao, Zhelei, 872, Xian 2 and 871 were between 2.9937-3.3471 mg・L-1 and to Qiushi, Baiyu, CA, Jingsong, JA, Furong and Xianghui were between 3.519-4.5665 mg・L-1 , respectively.It is indicated that the toxicities of chlorpyrifos to different hybrids of silkworm were different, and the two hybrids of silkworm Haoyue and 7532 were most sensitive.

  13. Community air monitoring for pesticides-part 2: multiresidue determination of pesticides in air by gas chromatography, gas chromatography-mass spectrometry, and liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Hengel, Matt; Lee, P

    2014-03-01

    Two multiresidue methods were developed to determine pesticides in air collected in California. Pesticides were trapped using XAD-4 resin and extracted with ethyl acetate. Based on an analytical method from the University of California Davis Trace Analytical Laboratory, pesticides were detected by analyzing the extract by gas chromatography-mass spectrometry (GC-MS) to determine chlorothalonil, chlorthal-dimethyl, cycloate, dicloran, dicofol, EPTC, ethalfluralin, iprodione, mefenoxam, metolachlor, PCNB, permethrin, pronamide, simazine, trifluralin, and vinclozolin. A GC with a flame photometric detector was used to determine chlorpyrifos, chlorpyrifos oxon, diazinon, diazinon oxon, dimethoate, dimethoate oxon, fonophos, fonophos oxon, malathion, malathion oxon, naled, and oxydemeton. Trapping efficiencies ranged from 78 to 92 % for low level (0.5 μg) and 37-104 % for high level (50 and 100 μg) recoveries. Little to no degradation of compounds occurred over 31 days; recoveries ranged from 78 to 113 %. In the California Department of Food and Agriculture (CDFA) method, pesticides were detected by analyzing the extract by GC-MS to determine chlorothalonil, chlorpyrifos, cypermethrin, dichlorvos, dicofol, endosulfan 1, endosulfan sulfate, oxyfluorfen, permethrin, propargite, and trifluralin. A liquid chromatograph coupled to a MS was used to determine azinphos-methyl, chloropyrifos oxon, DEF, diazinon, diazinon oxon, dimethoate, dimethoate oxon, diuron, EPTC, malathion, malathion oxon, metolachlor, molinate, norflurazon, oryzalin, phosmet, propanil, simazine and thiobencarb. Trapping efficiencies for compounds determined by the CDFA method ranged from 10 to 113, 22 to 114, and 56 to 132 % for 10, 5, and 2 μg spikes, respectively. Storage tests yielded 70-170 % recovery for up to 28 days. These multiresidue methods represent flexible, sensitive, accurate, and cost-effective ways to determine residues of various pesticides in ambient air. PMID:24370860

  14. 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

  15. Behavioral swimming effects and acetylcholinesterase activity changes in Jenynsia multidentata exposed to chlorpyrifos and cypermethrin individually and in mixtures.

    Science.gov (United States)

    Bonansea, Rocío Inés; Wunderlin, Daniel Alberto; Amé, María Valeria

    2016-07-01

    The pesticides cypermethrin (CYP) and chlorpyrifos (CPF) were found together in water bodies located in agricultural and urban areas. However, the impact to non-target biota from exposure to mixtures has received little attention. In the current study, we evaluated changes in swimming behavior and cholinesterase enzymes activity in Jenynsia multidentata, to investigate the possible effects of these insecticides individually and in mixtures. Moreover, differences between technical and commercial mixtures of the pesticides were evaluated. Females of J. multidentata were exposed over 96-h to CYP (0.04 and 0.4µgL(-1)), CPF (0.4 and 4µgL(-1)), individually and in a technical and commercial mixtures. Swimming behavior was recorded after 24h and 96h of exposure. Also, we measured cholinesterase enzymes activity in brain and muscle after 96h of exposure. Exposure to CYP increased the exploratory activity of J. multidentata in the upper area of the aquarium. Fish exposed to CPF (4µg L(-1)) showed a decrease in swimming activity and an increase in the time spent at the bottom of the aquarium. Interestingly, fish exposed to the technical and commercial mixture of CYP and CPF displayed a different behavior based on the concentration of exposure. Low concentration of pesticides elicited an increase in J. multidentata swimming activity with preference for the upper area of the aquarium, and high concentrations caused decrease in swimming activity with preference for the bottom area of the aquarium. Based on the response of cholinesterase enzymes, acetylcholinesterase in muscle was more sensitive to exposure to CYP, CPF and their mixtures than in brain. A decrease in swimming behavior correlates significantly with the inhibition of acetylcholinesterase activity in muscle of J. multidentata exposed to high concentrations of pesticides. These results draw attention to the need of more studies on the potential ecotoxicological impact of pesticides and its mixtures at

  16. Inulin Supplementation Lowered the Metabolic Defects of Prolonged Exposure to Chlorpyrifos from Gestation to Young Adult Stage in Offspring Rats

    Science.gov (United States)

    Reygner, Julie; Lichtenberger, Lydia; Elmhiri, Ghada; Dou, Samir; Bahi-Jaber, Narges; Rhazi, Larbi; Depeint, Flore; Bach, Veronique

    2016-01-01

    Increasing evidence indicates that chlorpyrifos (CPF), an organophosphorus insecticide, is involved in metabolic disorders. We assess the hypothesis whether supplementation with prebiotics from gestation to adulthood, through a modulation of microbiota composition and fermentative activity, alleviates CPF induced metabolic disorders of 60 days old offspring. 5 groups of Wistar rats, from gestation until weaning, received two doses of CPF pesticide: 1 mg/kg/day (CPF1) or 3.5 mg/kg/day (CPF3.5) with free access to inulin (10g/L in drinking water). Then male pups received the same treatment as dams. Metabolic profile, leptin sensitivity, insulin receptor (IR) expression in liver, gut microbiota composition and short chain fatty acid composition (SCFAs) in the colon, were analyzed at postnatal day 60 in the offspring (PND 60). CPF3.5 increased offspring’s birth body weight (BW) but decreased BW at PND60. Inulin supplementation restored the BW at PND 60 to control levels. Hyperinsulinemia and decrease in insulin receptor β in liver were seen in CPF1 exposed rats. In contrast, hyperglycemia and decrease in insulin level were found in CPF3.5 rats. Inulin restored the levels of some metabolic parameters in CPF groups to ranges comparable with the controls. The total bacterial population, short chain fatty acid (SCFA) production and butyrate levels were enhanced in CPF groups receiving inulin. Our data indicate that developmental exposure to CPF interferes with metabolism with dose related effects evident at adulthood. By modulating microbiota population and fermentative activity, inulin corrected adult metabolic disorders of rats exposed to CPF during development. Prebiotics supply may be thus considered as a novel nutritional strategy to counteract insulin resistance and diabetes induced by a continuous pesticide exposure. PMID:27760213

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

    Science.gov (United States)

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

    2007-03-01

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

  18. Chlorpyrifos-induced hormesis in insecticide-resistant and -susceptible Plutella xylostella under normal and high temperatures.

    Science.gov (United States)

    Deng, Z Z; Zhang, F; Wu, Z L; Yu, Z Y; Wu, G

    2016-06-01

    Hormesis induced by insecticides at the dosage lower than what ostensibly directly causes death on insects was studied. This paper reports the effects of the in vivo application of varied concentrations of chlorpyrifos (CPF) on Plutella xylostella (DBM). The insecticide concentrations applied included 0.000025-2.5 mg l-1, which are far lower than LC1 (7.2 mg l-1), for the CPF-susceptable (Si) DBM, and 250 mg l-1 which is far below LC1 (1286 mg l-1), for the CPF-resistant (Rc) DBM, as well as LC10- and LC50-doses for both strains. Significant hormesis was found with the 'hermetic-CPFs', i.e., 0.0025 mg l-1 for Si DBM and 2.5 mg l-1 for Rc DBM, at the normal or high temperature either in a 24 h or under a long-term treatment. These doses of CPF significantly stimulated the development and increased the fecundity of Si and Rc DBM at 25°C with approximately 23.5-29.8% activity increase on acetylcholinesterase (AChE) and 30.5-91.3% increase on glutathione S-transferases (GSTs) at 25 or 38°C in 4-24 h. The enzymatic activities were significantly reduced by LC50-CPF at 25°C in vivo, but the inhibition was relieved significantly, if the insects were first subjected to a hormetic-CPF pretreatment. It was remarkable that the average rates of enzymatic activity increase were 67.5-76.6% for AChE and 366-546% for GSTs. Consequently, it was concluded that the hormesis on Si and Rc DBM could be induced by CPF doses far below LC1 at normal or high temperature in short- or long-term treatment. These findings might help to improve the current insect control practices in the field. PMID:27241230

  19. Dissipation and adsorption of isoproturon, tebuconazole, chlorpyrifos and their main transformation products under laboratory and field conditions.

    Science.gov (United States)

    Papadopoulou, Evangelia S; Karas, Panagiotis A; Nikolaki, Sofia; Storck, Veronika; Ferrari, Federico; Trevisan, Marco; Tsiamis, George; Martin-Laurent, Fabrice; Karpouzas, Dimitrios G

    2016-11-01

    Assessment of dissipation constitutes an integral part of pesticides risk assessment since it provides an estimate of the level and the duration of exposure of the terrestrial ecosystem to pesticides. Within the frame of an overall assessment of the soil microbial toxicity of pesticides, we investigated the dissipation of a range of dose rates of three model pesticides, isoproturon (IPU), tebuconazole (TCZ), and chlorpyrifos (CHL), and the formation and dissipation of their main transformation products following a tiered lab-to-field approach. The adsorption of pesticides and their transformation products was also determined. IPU was the least persistent pesticide showing a dose-dependent increase in its persistence in both laboratory and field studies. CHL dissipation showed a dose-dependent increase under laboratory conditions and an exact opposite trend in the field. TCZ was the most persistent pesticide under lab conditions showing a dose-dependent decrease in its dissipation, whereas in the field TCZ exhibited a biphasic dissipation pattern with extrapolated DT90s ranging from 198 to 603.4days in the ×1 and ×2 dose rates, respectively. IPU was demethylated to mono- (MD-IPU) and di-desmethyl-isoproturon (DD-IPU) which dissipated following a similar pattern with the parent compound. CHL was hydrolyzed to 3,5,6-trichloro-2-pyridinol (TCP) which dissipated showing a reverse dose-dependent pattern compared to CHL. Pesticides adsorption affinity increased in the order IPUpesticides and their transformation products will be used as exposure inputs for assessment of their soil microbial toxicity. PMID:27341109

  20. Bacterial community analysis in chlorpyrifos enrichment cultures via DGGE and use of bacterial consortium for CP biodegradation.

    Science.gov (United States)

    Akbar, Shamsa; Sultan, Sikander; Kertesz, Michael

    2014-10-01

    The organophosphate pesticide chlorpyrifos (CP) has been used extensively since the 1960s for insect control. However, its toxic effects on mammals and persistence in environment necessitate its removal from contaminated sites, biodegradation studies of CP-degrading microbes are therefore of immense importance. Samples from a Pakistani agricultural soil with an extensive history of CP application were used to prepare enrichment cultures using CP as sole carbon source for bacterial community analysis and isolation of CP metabolizing bacteria. Bacterial community analysis (denaturing gradient gel electrophoresis) revealed that the dominant genera enriched under these conditions were Pseudomonas, Acinetobacter and Stenotrophomonas, along with lower numbers of Sphingomonas, Agrobacterium and Burkholderia. Furthermore, it revealed that members of Bacteroidetes, Firmicutes, α- and γ-Proteobacteria and Actinobacteria were present at initial steps of enrichment whereas β-Proteobacteria appeared in later steps and only Proteobacteria were selected by enrichment culturing. However, when CP-degrading strains were isolated from this enrichment culture, the most active organisms were strains of Acinetobacter calcoaceticus, Pseudomonas mendocina and Pseudomonas aeruginosa. These strains degraded 6-7.4 mg L(-1) day(-1) of CP when cultivated in mineral medium, while the consortium of all four strains degraded 9.2 mg L(-1) day(-1) of CP (100 mg L(-1)). Addition of glucose as an additional C source increased the degradation capacity by 8-14 %. After inoculation of contaminated soil with CP (200 mg kg(-1)) disappearance rates were 3.83-4.30 mg kg(-1) day(-1) for individual strains and 4.76 mg kg(-1) day(-1) for the consortium. These results indicate that these organisms are involved in the degradation of CP in soil and represent valuable candidates for in situ bioremediation of contaminated soils and waters.

  1. Research Advances of a Kind of Organophosphate Pesticide Chlorpyrifos%有机磷农药毒死蜱研究进展

    Institute of Scientific and Technical Information of China (English)

    王川; 周巧红; 吴振斌

    2011-01-01

    As an alternative to highly toxic organophosphate pesticide, chlorpyrifos was used widely in China. With the raising consumption, it has been a main source of pesticide contamination. Hot topics in the chlorpyrifos studies were surmmerized, including its environmental behavior, its impact on soil, plants and aquatic organism, its microbial degradation. The research prospects were also proposed.%毒死蜱作为替代高毒有机磷类农药的主要品种,在我国应用日益广泛。随着用量的增加,势必加大该类农药污染的程度。文章综述了毒死蜱的研究热点问题,主要包括毒死蜱的环境行为,对土壤酶和微生物、植物及水生生物的影响,以及毒死蜱的微生物降解等;同时对未来研究方向进行了展望。

  2. Cholinergic synaptic signaling mechanisms underlying behavioral teratogenicity : Effects of nicotine, chlorpyrifos, and heroin converge on protein kinase C translocation in the intermedial part of the hyperstriatum ventrale and on imprinting behavior in an avian model

    NARCIS (Netherlands)

    Izrael, M; Van der Zee, EA; Slotkin, TA; Yanai, J; Slotkin, Theodore A.

    2004-01-01

    A wide variety of otherwise unrelated neuroteratogens elicit a common set of behavioral defects centering around cholinergic contributions to cognitive function. We utilized the developing chick to overcome confounds related to maternal effects and compared the actions of nicotine, chlorpyrifos, and

  3. Variation in susceptibility of laboratory and field strains of three stored-grain insect species to beta-cyfluthrin and chlorpyrifos-methyl plus deltamethrin applied to concrete surfaces

    Science.gov (United States)

    The efficacy of beta-cyfluthrin and chlorpyrifos-methyl plus deltamethrin applied to clean, concrete floors of empty bins prior to grain storage against field strains of stored-grain insects is unknown. We exposed adults of 16 strains of the red flour beetle, Tribolium castaneum (Herbst); 8 strains ...

  4. 毒死蜱对大鳞副泥鳅的急性毒性及遗传毒性研究%Studies on Acute Toxicity and Genetic Toxicity of Chlorpyrifos to Paramisgurnus dabryanus

    Institute of Scientific and Technical Information of China (English)

    夏晓华; 张林霞; 王莉娜; 杜启艳; 常重杰

    2013-01-01

    为了估测毒死蜱的环境毒性,以大鳞副泥鳅为试验动物,设置毒死蜱对其急性毒性和遗传毒性试验,研究毒死蜱对大鳞副泥鳅的半数致死质量浓度(LC50)和红细胞DNA的损伤程度.结果表明:毒死蜱对大鳞副泥鳅24、48、96 h的LQ0分别为524.76、291.53、193.20 μg/L,安全质量浓度(SC)为26.99 μg/L;试验各组(毒死蜱质量浓度分别为26.99、45.11、63.23 μg/L)的红细胞微核率均高于空白对照组,其最高微核率出现在最高剂量组(63.23 μg/L)染毒后的第6天,为4.111‰,微核率与毒死蜱质量浓度和染毒时间呈正相关.毒死蜱具有较强的环境毒性,并表现出明显的时间-剂量效应.%The purpose of this study was to evaluate the environmental toxicity of chlorpyrifos. With Paramisgurnus dabryanus as test animal,experiments on the acute toxicity and genetic toxicity of chlorpyrifos were performed to survey the LC50 and the genetic damage of chlorpyrifos to Paramisgurnus dabryanus. The results showed that the LC50 of chlorpyrifos at 24 h,48 h and 96 h was 524. 76 μg/L,291. 53 μg/L and 193. 20 μg/L,respectively,and its safety concentration was 26. 99 μg/L. The micronucleus rates of treatment groups with chlorpyrifos at 26. 99 μg/L, 45. 11 μg/L and 63. 23 μg/L were higher than those of the control group. The highest micronucleus rate was 4. lll‰,appearing on the 6 th day in the highest concentration test group. The micro-nucleus rates manifested positive correlation with the test time and test dose of chlorpyrifos. Chlorpyrifos had a strong environmental toxicity and showed a significant time-dose effect.

  5. Interaction between chlorpyrifos and hepatic microsomal cytochrome P450 enzyme system in fish%毒死蜱与鱼肝微粒体P450的相互作用

    Institute of Scientific and Technical Information of China (English)

    边文杰; 徐燕; 李少南; 朱国念

    2011-01-01

    为了评估毒死蜱对水生生态系统的风险,比较研究了毒死蜱对斑马鱼、麦穗鱼及太阳鱼的急性毒性,3种鱼肝微粒体P450酶系对毒死蜱的脱硫转化作用及毒死蜱对肝微粒体P450酶系的影响.结果表明,毒死蜱对斑马鱼、麦穗鱼及太阳鱼的96 h-LC50分别为1.94,0.0273,0.0681 mg·L-1.3种鱼肝微粒体P450酶系对毒死蜱代谢的Vmax/Km值分别为:1.67×104,5.00×104,2.00× 104,即代谢能力大小为麦穗鱼>太阳鱼>斑马鱼,与急性毒性试验结果相吻合,从而P450酶系的脱硫转化活性可以一定程度上解释毒死蜱对3种鱼的毒性差异.试验浓度毒死蜱对3种鱼的P450酶系的影响不显著.%Acute toxicity of chlorpyrifos to Danio rerio, Pseudorasboraparva, and Lepomis gibbosus, oxidative activation of chlorpyrifos catalyzed by hepatic microsomal cytochrome P450 system, and influence of chlorpyrifos to the P450 system were studied to evaluate the risk of chlorpyrifos on ecology system. 96 h LC50 of chlorpyrifos to the Dani-o rerio, the Pseudorasbora parva, and the Lepomis gibbosus was measured to be 1. 94, 0. 0273, 0. 0681 mg·L-1, respectively. The Vmax/Km of chlorpyrifos oxidation catalyzed by P450 system was measured to be 1. 67 × 104 , 5. 00 × 104, 2. 00 × 104 , respectively, indicating that the oxidative metabolism capacity of the P450 system was the highest in Pseudorasbora parva and the lowest in Danio rerio, which matched the results of acute toxicity tests. The influence of chlorpyrifos to the P450 system was not obvious.

  6. Biochemical and molecular evidences on the protection by magnesium oxide nanoparticles of chlorpyrifos-induced apoptosis in human lymphocytes

    Directory of Open Access Journals (Sweden)

    Vida Heydary

    2015-01-01

    Full Text Available Background: Chlorpyrifos (CP is one of the most widely used organophosphate (OP insecticides in agricultural and residential pest control with its attendant adverse health effect. In the present study, it is proposed to investigate the possible modulatory role of magnesium oxide nanoparticles (MgO NPs against CP-induced toxicity in human lymphocytes and determine the mechanisms lying behind this protection by viability and biochemical assays. Materials and Methods: Isolated lymphocytes were exposed to 12 μg/mL CP either alone or in combination with different concentrations of MgO NPs (0.1 μg/mL, 1 μg/mL, 10 μg/mL, and 100 μg/mL. After a 3-day incubation, the viability and oxidative stress markers including cellular mitochondrial activity, caspase-3 and -9 activities, total antioxidant power, lipid peroxidation, and myeloperoxidase (MPO activity were measured. Also, the levels of tumor necrosis factor-α (TNF-α as inflammatory index, along with acetylcholinesterase (AChE activity were measured. Statistical differences were determined using one-way analysis of variance (ANOVA and Dunnett′s multiple comparison tests. Results: It is indicated that CP-exposed lymphocytes treated with MgO NPs resulted in a substantial reduction in the pace of mortality as well as the stages of oxidative stress in a dose-dependent manner. Also, MgO NPs (100 μg/mL meaningfully restored CP-induced increase of TNF-α (P < 0.001 and decrease of AChE activity (P < 0.001 and were capable of preventing CP-treated human lymphocytes from apoptosis (P < 0.001. Conclusion: Our results demonstrate that MgO NPs in approximate 100 nm diameter not only make cells resistant to the toxic properties of CP but also attenuate toxic effects of CP, which is demonstrating the potential of MgO NPs to be applied in future immune deficiency therapeutic strategies.

  7. Determination of Chlorpyrifos Residue in Apples and Their Processing Products by GC%GC测定毒死蜱在苹果及其加工制品中的残留

    Institute of Scientific and Technical Information of China (English)

    许高政; 周力; 王茜; 王明林

    2013-01-01

    The field spraying method was used to sprayed chlorpyrifos pesticide on apple trees. After simulating commercialization procedure to process apple juice,gas chromatography was employed to detect chlorpyrifos residue in apples,fresh apple juices and fruit juice concentrates. The results demonstrated that the commercialization process of juic-ing could decrease the chlorpyrifos residue effectively. Chlorpyrifos in fresh fruit juices were only 0.4%-24.2%of that in raw fruit materials.However,owing to the losing of water,chlorpyrifos residue in fruit juice concentrates increased greatly. The recovery of the method was 81.15%-106.02%, the relative standard devation was 7.6%-18.6%(n=5).%采用田间喷药方式对苹果树喷洒毒死蜱农药,然后模拟苹果汁商业化加工过程进行加工,利用气相色谱对苹果、鲜榨苹果汁以及浓缩果汁中的毒死蜱进行检测,结果表明,果汁商业化榨汁过程可有效降低农药残留,鲜榨果汁中的农药残留仅为原料果中的0.4%~24.2%,而浓缩果汁中由于水分的流失,农药残留会出现大幅的提高。该法加标回收率为81.15%~106.02%,测定结果的相对标准偏差为7.6%~18.6%(n=5)。

  8. Efficacy of Chlorpyrifos 5% GR against Bradysia odoriphaga%5%毒死蜱颗粒剂对韭蛆的防治效果

    Institute of Scientific and Technical Information of China (English)

    高远起; 易欣; 肖盈; 胡美英

    2012-01-01

    [Aims] The effect of chlorpyrifos 5% GR on Bradysia odoriphaga was investigated in this study. The control efficiency, optimal dosages and persistence were determined by field trial. [Methods] The field trial was carried out using the randomized block design, and the significance of difference was performed by Duncan's multiple range test (DMRT). [Results] At the concentration of 1875 g a.i./ha, chlorpyrifos 5% GR showed good control efficiency against Bradysia odoriphaga with control of 87.07 and 84.62% after 21 days after treatment in 2010 and 2011, respectively, and insect population control effect are 90.22 and 89.83%, respectively, which is obviously higher than that of phoxim 3% GR at 675 g a.i./ha. [Conclusions] At the concentration of 1875 g a.i./ha, chlorpyrifos 5% GR could be used to effectively control B. odoriphaga.%[目的]选用5%毒死蜱颗粒剂,通过对韭蛆(Bradysia odoriphaga)药效试验,明确药剂的防治效果、适宜用量、持效期.[方法]采用随机区组排列法进行田间试验,结果采用邓肯式新复极差法检验差异显著性.[结果]5%毒死蜱颗粒剂在1875 g a.i./hm2施用量下,2010、2011年试验结果表明:药后21 d的防效分别达87.07%和84.62%,21d虫口防效分别达90.22%和89.83%,显著高于对照药剂3%辛硫磷颗粒剂.[结论]建议田间施用1875 g a.i./hm2毒死蜱颗粒剂可有效防治韭蛆.

  9. Decline dynamics of chlorpyrifos microspheres and emulsifiable concentrate in water and its toxicity to the larvae of Aedes albopictus%毒死蜱微球和乳油在水中的消解动态及其对白纹伊蚊幼虫的毒力

    Institute of Scientific and Technical Information of China (English)

    杨石有; 刘德坤; 张翠; 张少飞; 邓振洲; 李正杨; 黄彬彬; 吴祖建; 吴刚

    2013-01-01

    The decline dynamics of different concentration of chlorpyrifos microspheres and chlorpyrifos emulsifiable concentrate(EC)in water,and the sustained toxicity of chlorpyrifos microspheres and chlorpyrifos EC to the 3rd larvae of Aedes albopictus were studied in laboratory.The results showed that the decline rate of chlorpyrifos microspheres was slower than that of chlorpyrifos EC,and the half-life of chlorpyrifos microspheres was longer than that of chlorpyrifos EC.The halflives of chlorpyrifos microspheres and EC were longer at high concentrations than those of the low concentrations.The half-lives of chlorpyrifos microspheres and chlorpyrifos EC at the dosage of 1.2,12,24mg/L were(19.4±2.1)d,(27.8± 1.6)d,(31.0±1.7)d and(12.8 ±1.0)d,(16.1 ±0.9)d,(19.7±1.1)d,respectively.The toxicity of chlorpyrifos microspheres to the 3rd instar larvae of A.albopictus was higher and the duration was longer than that of chlorpyrifos EC.After treatment for 85 days in water,the mortality of mosquito larvae caused by 1.2mg/L chlorpyrifos microspheres was 76.6%,which was higher than that of the same concentration of chlorpyrifos EC(53.3%).The results suggested chlorpyrifos microspheres had good persistence against mosquito larvae.%室内条件下,研究了不同浓度毒死蜱微球和毒死蜱乳油在水中的消解动态及其对白纹伊蚊Aedes albopictus3龄幼虫的持续毒杀作用.结果表明:毒死蜱微球在水中的消解速率比乳油慢,半衰期比乳油的长,高浓度微球和乳油的消解半衰期均长于低浓度下的消解半衰期.有效成分为1.2、12和24mg/L的毒死蜱微球和毒死蜱乳油在水中的消解半衰期分别为(19.4±2.1)d、(27.8±1.6)d、(31.0±1.7)d和(12.8±1.0)d、(16.1±0.9)d、(19.7±1.1)d;毒死蜱微球对白纹伊蚊3龄幼虫的毒杀作用强于乳油且持效期长,1.2mg/L的毒死蜱微球水解85 d后处理白纹伊蚊3龄幼虫的死亡率高达76.6%,高于相同浓度、相同条件乳油的处理(53.3%),具有良好的持效性.

  10. Degradation Characteristics of CB3,a Chlorpyrifos Degrading Bacteria Strain%1株毒死蜱降解菌的降解特性

    Institute of Scientific and Technical Information of China (English)

    卢洁; 曹明星; 李晓花; 梁同军; 鲍海鸥

    2013-01-01

    The degradation characteristics of CB3,a chlorpyrifos degrading bacteria strain isolated from soil and waste water contaminated by organophosphorus pesticide for long-term was studied.The results showed that there was a certain synchronism between CB3 growth and chlorpyrifos degradation rate and the degradation rate could be up to 89.6% when the growth of CB3 was the maximum.The degradation rate reached a higher level when the initial concentration was 200 ~ 800 mg/L but the degradation rate decreased gradually with increase of initial concentration when the concentration was above 800 mg/L.The degradation rate of the initial concentration with 2 000 mg/L was 32% only.The degradation rate of CB3 to chlorpyrifos rose with increase of inoculation level when the inoculation level was below 1 ml and there was no significant difference in degradation rate when the inoculation level was 1~2.5 ml.The degradation rate of CB3 to chlorpyrifos under pH 6.0~7.0 and 25~35℃ reached a higher level.CB3 grew well on triazophos,grew badly on malathion or omethoate and did not grow on fenthion or acephate,which indicates that CB3 is of the selectivity to the degradation of organophosphorus pesticide.%为弄清菌株 CB3对毒死蜱的降解特性,采用摇床振荡培养等方法,对从长期受有机磷农药污染的土壤和废水中分离出的1株毒死蜱降解菌的降解特性进行了研究。结果表明:CB3生长和对毒死蜱的降解作用具有一定的同步性,当其生长量最大时,对毒死蜱的降解率达89.6%。初始浓度200~800 mg/L时,CB3对毒死蜱的降解率较高;浓度高于800 mg/L 时,随着初始浓度的增加,降解率逐渐下降;当初始浓度为2000 mg/L 时,降解率仅32%。接种量低于1 mL 时,CB3对毒死蜱的降解率随着接种量增加而提高,当接种量在1~2.5 mL 时,CB3对毒死蜱降解率无明显差异。CB3在 pH6.0~7.0,25~35℃条件下对毒

  11. 毒死蜱—聚乳酸微球的制备及其性能评价%Preparation and characteristics analysis of microspheres of chlorpyrifos and polylactic acid

    Institute of Scientific and Technical Information of China (English)

    郭瑞峰; 黄彬彬; 杨晓伟; 吴祖建; 吴刚

    2011-01-01

    The sustained-release microspheres of chlorpyrifos was prepared by solvent evaporation method using biodegradable polylactic acid (PLA) as wall materials and chlorpyrifos as core materials. The effects of ratio between core materials to wall materials ( chlorpyrifos weight/ PLA weight, CP value) and the concentration of PLA on the characteristics of microsphere were investigated. The results indicated that particle diameter, drug-loading rate and entrapment efficiency of microsphere increased with the increase of the concentration of PLA. The particle diameter and drug-loading rate of microsphere decreased when the CP value was decreased from 1:2 to 1:5. When the CP value were 1:3 and 1: 4, the entrapment efficiency of microsphere were 89. 88% ± 1. 67% and 90. 55% ± 1. 86% , respectively. The smooth and intact microspheres of chlorpyrifos were formed when the CP value were lower than 1:2. The differential scanning calorimetry ( DSC) determination demonstrated that chlorpyrifos and PLA were combined well to form the microspheres. The results indicated that the appropriate concentration of PLA and CP value contributes to the property of the chlorpyrifos microspheres.%以毒死蜱为芯材,以生物可降解材料聚乳酸(PLA)为载体(壁材),采用溶剂挥发法制备了毒死蜱缓释微球,考察了芯壁材质量比及聚乳酸浓度对微球质量的影响.结果表明:当聚乳酸浓度增加时,载药量和包封率、粒径均随之增加;当芯壁材质量比减小(由1:2减小至1:5)时,微球粒径、载药量也逐渐减小;包封率在芯壁材质量比为1:3和1:4时分别为89.88%±1.67%和90.55%±1.86%;当芯壁材质量比小于1∶2时,微球呈光滑完整的球形.差示扫描量热检测分析证明,毒死蜱和聚乳酸能够有机地结合为一体.表明合适的芯壁材比例和聚乳酸浓度有利于提高制备微球的质量.

  12. Sublethal effect of chlorpyrifos on the population dynamics of an experimental Tetranychus urticae Koch population%毒死蜱亚致死剂量对二斑叶螨实验种群动态的影响

    Institute of Scientific and Technical Information of China (English)

    涂洪涛; 张金勇; 陈汉杰

    2016-01-01

    【目的】为探讨毒死蜱(Chlorpyrifos)对二斑叶螨Tetranychus urticae Koch种群动态的影响,室内研究了毒死蜱亚致死剂量对二斑叶螨实验种群成螨和若螨的生长发育、存活和繁殖情况的影响。【方法】用浸虫法进行测定,生命表方法分析亚致死效应。【结果】结果表明毒死蜱亚致死剂量 LC25处理成螨后,雌成螨寿命、总产卵量、子代孵化率、性比与对照组无显著差异,其净增值率、内禀增长率、周限增长率以及种群加倍时间显著低于对照组。毒死蜱亚致死剂量 LC25处理若螨后,总产卵量、净增值率、世代平均周期显著低于对照组,内禀增长率、周限增长率以及种群加倍时间与对照组无显著差异。扩散试验证明毒死蜱对二斑叶螨有较强的刺激扩散作用。【结论】以上结果说明毒死蜱亚致死剂量对不同发育阶段的二斑叶螨发育和繁殖的影响不同,毒死蜱对二斑叶螨的刺激扩散作用可能是引起二斑叶螨再猖獗的原因之一。%Objectives] To investigate the effects of chlorpyrifos onTetranychus urticae Koch population dynamics, specifically the sublethal effects of chlorpyrifos on the development, survival rate and reproduction ofT. urticae. [Methods] Toxicity was tested using the pest-dipping method and the sublethal effects of chlorpyrifos determined by means of life tables. [Results]Female fecundity, adult female longevity, F1hatchability, and the sex ratio ofT. urticae treated with a sublethal concentration (LC25) of chlorpyrifos were not significantly different to those of the control, however, the net reproductive rate, intrinsic rate of natural increase, finite rate of increase, and population doubling time, were all significantly lower than those of the control. Female fecundity, net reproductive rate, and mean generation time ofT. urticae nymphs treated with a sublethal concentration (LC25) of chlorpyrifos were

  13. The Sea Urchin Embryo, an Invertebrate Model for Mammalian Developmental Neurotoxicity, Reveals Multiple Neurotransmitter Mechanisms for Effects of Chlorpyrifos: Therapeutic Interventions and a Comparison with the Monoamine Depleter, Reserpine

    OpenAIRE

    Buznikov, Gennady A; Nikitina, Lyudmila A.; Rakić, Ljubiša M.; Miloševi, Ivan; Bezuglov, Vladimir V.; Lauder, Jean M.; Slotkin, Theodore A.

    2007-01-01

    Lower organisms show promise for the screening of neurotoxicants that might target mammalian brain development. Sea urchins use neurotransmitters as embryonic growth regulatory signals, so that adverse effects on neural substrates for mammalian brain development can be studied in this simple organism. We compared the effects of the organophosphate insecticide, chlorpyrifos in sea urchin embryos with those of the monoamine depleter, reserpine, so as to investigate multiple neurotransmitter mec...

  14. Acute Toxicity of Atrazine, Endosulfan Sulphate and Chlorpyrifos to Vibrio fischeri , Thamnocephalus platyurus and Daphnia magna, Relative to Their Concentrations in Surface Waters from the Alentejo Region of Portugal

    OpenAIRE

    Palma, P.; Palma, V.; R. Fernandes; Soares, A.; Barbosa, I.

    2008-01-01

    Abstract Ecotoxicological effects of the herbicide atrazine and the insecticides endosulfan sulphate and chlorpyrifos were evaluated using a test battery comprising aquatic organisms from different trophic levels. According to the categories established in the EU legislation, atrazine can be considered non-harmful for the species tested, while the insecticides can be considered very toxic for the crustaceans. The results of acute toxicity tests showed that the sensitivity of organisms were a...

  15. Experimental hut evaluation of bednets treated with an organophosphate (chlorpyrifos-methyl) or a pyrethroid (lambdacyhalothrin) alone and in combination against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes.

    OpenAIRE

    Corbel Vincent; Chandre Fabrice; Hougard Jean-Marc; Curtis Christopher F; Koffi Alphonsine A; N'Guessan Raphael; Asidi Alex N; Darriet Frédéric; Zaim Morteza; Rowland Mark W

    2005-01-01

    Abstract Background Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments. Methods Comparative studies of chlorpyrifos-methyl (CM), an organophosphate with low mammalian toxicity, and lambdacyha...

  16. Biodegradation Status and Prospect of Chlorpyrifos and its Intermediate TCP%毒死蜱及其中间体TCP的微生物降解研究现状及展望

    Institute of Scientific and Technical Information of China (English)

    段海明

    2012-01-01

    This was a review about the biodegradation of chlorpyrifos and TCP. The important role about the bio- degradation of TCP for the removal of chlorpyrifos contamination was clarified. In the end of the paper, the au- thor gave the future direction about dation for the wastewater discharged the treatment of chlorpyrifos pollution, especially about the microbial degra- from pesticide enterprises.%本文就国内外毒死蜱及其中间体TCP(3,5,6-三氯-2-吡啶酚(钠))降解菌的分离筛选及其降解特性研究作一综述,指出了TCP的生物降解对毒死蜱彻底降解的重要作用。最后针对毒死蜱污染的去除,尤其对毒死蜱生产企业的废水处理作出了展望。

  17. Characterization of cholinesterases present in brain and muscle tissues of juvenile blue shark (Prionace glauca

    Directory of Open Access Journals (Sweden)

    Luís Miguel Fonseca Alves

    2014-06-01

    Regarding the in vitro exposure to chlorpyrifos-oxon, we have observed a dose-response pattern showing higher ChE inhibitions with increasing pesticide concentrations and with more than 90% inhibition in the highest concentrations, which reveals the potential of this biomarker for biomonitoring studies and contaminant effect assessment in the blue shark.

  18. Organophosphorus (OP) Pesticide Degradation in the Presence of Chlorinated Oxidants: Kinetics, Modeling, and Structure-Activity Relationships

    Science.gov (United States)

    The rates and pathways for pesticide transformation during drinking water treatment are known for only a few pesticides and under limited conditions. The resulting oxons are more toxic than the parent pesticides. The transformation rates and pathways for chlorpyrifos, an OP pest...

  19. 多杀菌素·毒死蜱微球高效液相色谱分析%HPLC Analysis Research of Spinosad Chlorpyrifos Microsphere

    Institute of Scientific and Technical Information of China (English)

    刘德坤; 张翠; 杨石有; 吴祖建; 吴刚

    2012-01-01

    [Aims] A method was developed for the quantitative determination of spinosad and chlorpyrifos under the same HPLC condition. [Methods] The mobile phase was a mixture of methanol, acetonitrile and 0.05% acetic sodium solution (45 :45 : 10, by vol), and the flow rate was 1.0 mL/min. A Amethyst C18-H and a UV wavelength detector were used with column temperature at 20 °C and the detection wave length was 250 nm. [Results] For the detection methods of spinosad and chlorpyrifos, the standard deviations were 0.0541 and 0.0701, coefficients of variation were 0.621 'and 0.578%, average recovery rate were 97.45 and 100.03%, and linear correlation coefficient were 0.9999, 0.9997, respectively. [Conclusions] The method in this study displayed the advantages of convenience, shortcut, good separation, high precision and accuracy, and good linear correlations.%[目的]建立了在同一液相色谱条件下测定多杀菌素和毒死蜱的定量分析方法.[方法]以甲醇-乙腈-0.05%乙酸钠溶液(体积比45∶45∶10)为流动相,流速为1.0 mL/min,使用Amethyst C18-H色谱柱,紫外波长检测器,柱温为20℃,选择250 nm为检测波长进行检测.[结果]方法对于多杀菌素和毒死蜱组分的标准偏差分别为0.0541、0.0701,变异系数为0.621%、0.578%,平均回收率为97.45%、100.03%,线性相关系数为0.9999、0.9997.[结论]该方法具有简便、快捷、分离效果好、精密度和准确度高、线性关系好的特点.

  20. Research on the Preparation and Performance of Chlorpyrifos' Molecularly Imprinted Polymers%毒死蜱分子印迹聚合物的制备与性能研究

    Institute of Scientific and Technical Information of China (English)

    郑红; 张迎雪

    2011-01-01

    As a new technique of recent development, molecular imprinting technique (MIT) with predetermination, specific recognition and practicability is widely used in the domain of environment, biological medicines, and so on. It also has important research potential in food security test. In this paper, using chlorpyrifos as template, the molecular imprinted polymers was prepared by in situ step-addition polymerization. The characteristics of selective separation and pre-concentration for chlorpyrifos, dichlorovos and methamidophos were examined on the polymer. The chlorpyrifos from the honey, vegetables and natural water was extracted via using the polymer. The extraction conditions of MISPE column for chlorpyrifos were optimized. The results indicated that different kinds of recognition sites in the MIPs showed specific affinity toward chlorpyrifos. Velocity is 1.0 Ml · Min-1 , the sampling volume of 20 Μl. Average recoveries for chlorpyrifos in a blank sample spiked at 3 levels were between 96.0 %and 102% , with a RSD of less than 6. 6%. This method is easily operated, highly selective and has no requirement of complicated sample pretreatment and is applicable for the determination of chlorpyrifos residue in foods.%分子印迹技术是近些年发展起来的一种新技术,因其具有构效预定性、特异识别性和广泛实用性等特点而被广泛应用于环境、生物医药等领域,其在食品安全检测中也有重要的研究潜力.以毒死蜱为模板分子,采用原位逐步聚合法制备了具有良好识别性能的分子印迹聚合物(MIPs),考察了毒死蜱、敌敌畏及甲胺磷在毒死蜱分子聚合物上的选择性分离富集特性.用毒死蜱分子聚合物固相萃取了蜂蜜、蔬菜和天然水中的毒死蜱.结果表明,聚合物对模板分子产生了印迹效应,对毒死蜱有明显的选择性,流速为1.0 mL·min -1,进样量为20 μL,加样回收率为96%~102%,RSD小于6.6%.该方法操作简单,针对性

  1. Study on Toxicity Effect of Abamectin and Chlorpyrifos on Grass Carp ( Ctenopharyngodon idllus )%阿维菌素·毒死蜱对草鱼的毒性效应研究

    Institute of Scientific and Technical Information of China (English)

    李常健; 骆鹰; 杨锦兀; 陈龙; 蒋琼凤

    2011-01-01

    [目的]探讨阿维菌素、毒死蜱2种药物对草鱼的毒性效应及相互关系.[方法]以健康活泼的草鱼为试验对象,用阿维菌素、毒死蜱分别对其进行单一药物的急性毒性和2种药物组合和联合毒性试验.[结果]阿维菌素、毒死蜱、2种药物混合对草鱼24、48、72、96h的LC分别为:阿维菌素0.54、0.49、0.17、0.10 mg/L;毒死蜱0.29、0.21、0.12、0.05 mg/L;阿维菌素与毒死蜱混合药1.22、1.08、0.99、0.86 mg/L;其对草鱼的安全浓度(SC)分别为:0.010、0.005、0.086 mg/L.药物的毒性大小依次为:毒死蜱>阿维菌素>混合药.[结论]阿维菌素和毒死蜱混合药的不同浓度对草鱼的生长有显著影响,浓度越高毒性作用越大,低毒性强度的阿维菌素对毒死蜱具缓解作用.%[ Objective ] The study aimed to discuss the toxicity effect of Abamectin and Chlorpyrifos on grass carp ( Ctenopharyngodon idllus) and their interrelations. [ Method ] Taking healthy and active gass carp as the object, the acute toxicity test of single pesticide and the joint toxicity test of two pesticides on grass carp were carried out. [ Result ] The LC50 of Abamectin and Chlorpyrifos and the mixture of two pesticides against grass carp at 24,48,72 and 96 h were as follows, Abamectin :0. 54,0.49,0. 17 and 0. 10 mg/L; Chlorpyrifos :0. 29,0. 21,0. 12 and 0.05 mg/L; the mixture of two pesticides:l.22,1.08,0.99 and0. 86 mg/L. The safe concentration (SC) of Abamectin,Chlorpyrifos and the mixture of two pesticides were 0.010,0. 005 and 0. 086 mg/L,respectively. The toxicity of the pesticides in sequence was Chlorpyrifos > Abamectin > the mixture of two pesticides. [ Conclusion] Different concentrations of Abamectin,Chlorpyrifos and the mixture of two pesticides had remarkable effect on the growth of grass carp,the higher the concentration was,the greater the toxicity effect was. Abamectin at low toxicity intensity had antagonistic effects on Chlorpyrifos.

  2. 毒死蜱对斜生栅藻急、慢性毒性效应的研究%Acute and Chronic Toxicity of Chlorpyrifos to Scenedesmus obliquus

    Institute of Scientific and Technical Information of China (English)

    葛顺; 陈敏东; 宋玉芝; 邱伟健; 龚旋; 周军英; 单正军; 范晓龙

    2013-01-01

    To understand toxic effects of pollution by organophosphorus pesticide as chlorpyrifos on the local aquatic sensitive species as Scenedesmus obliquus, under laboratory conditions, based on the static toxicity test, the acute toxic effects of chlorpyrifos on Scenedesmus obliquus for 96h were investigated. Based on the acute test, the chronic experiments were also done, in which the contents of chlorophyll a, soluble protein and MDA in Scenedesmus obliquus were analyzed for different concentrations of chlorpyrifos in 14 d. Results showed that the 96 h EC50 of chlorpyrifos was 8.4 mg/L and no obvious toxic effect of chlorpyrifos was observed in chlorophyll a of Scenedesmus obliquus. However in the short time,the contents of solute protein and MDA were increased by low concentration of chlorpyrifos, but under the after effect of stress for a long time, the contents of total soluble protein and MDA could be reduced, which indicated that the two indexes of soluble protein and MDA were sensitive to chlorpyrifos such that they could be used as biological markers for influence of organophosphorus pesticide on aquatic organisms. Results could be considered as theoretical basis for protecting local aquatic sensitive species and establishing the criteria on safety use of pesticide.%为了解有机磷农药毒死蜱污染对本土水生敏感性物种斜生栅藻的毒性效应,在实验室条件下采用静态毒性实验,研究了毒死蜱对斜生栅藻96h急性毒性效应,并在急性试验基础上进行慢性试验,分析了不同浓度毒死蜱存在14 d后斜生栅藻叶绿素含量、可溶性蛋白以及丙二醛含量.结果表明,毒死蜱96 h EC50为8.4 mg/L;毒死蜱对斜生栅藻叶绿素a无明显毒性效应;但在前期短时间,低浓度作用下能促进可溶蛋白、MDA含量的上升,但在后期长时间胁迫作用下,总体可溶蛋白、MDA含量呈下降趋势;这说明,可溶蛋白和MDA这两个指标对毒死蜱敏感,可作为生物标志

  3. Alterations in juvenile diploid and triploid African catfish skin gelatin yield and amino acid composition: Effects of chlorpyrifos and butachlor exposures.

    Science.gov (United States)

    Karami, Ali; Karbalaei, Samaneh; Zad Bagher, Fariba; Ismail, Amin; Simpson, Stuart L; Courtenay, Simon C

    2016-08-01

    Skin is a major by-product of the fisheries and aquaculture industries and is a valuable source of gelatin. This study examined the effect of triploidization on gelatin yield and proximate composition of the skin of African catfish (Clarias gariepinus). We further investigated the effects of two commonly used pesticides, chlorpyrifos (CPF) and butachlor (BUC), on the skin gelatin yield and amino acid composition in juvenile full-sibling diploid and triploid African catfish. In two separate experiments, diploid and triploid C. gariepinus were exposed for 21 days to graded CPF [mean measured: 10, 16, or 31 μg/L] or BUC concentrations [Mean measured: 22, 44, or 60 μg/L]. No differences in skin gelatin yield, amino acid or proximate compositions were observed between diploid and triploid control groups. None of the pesticide treatments affected the measured parameters in diploid fish. In triploids, however, gelatin yield was affected by CPF treatments while amino acid composition remained unchanged. Butachlor treatments did not alter any of the measured variables in triploid fish. To our knowledge, this study is the first to investigate changes in the skin gelatin yield and amino acid composition in any animal as a response to polyploidization and/or contaminant exposure. PMID:27182978

  4. Removal of carbofuran is not affected by co-application of chlorpyrifos in a coconut fiber/compost based biomixture after aging or pre-exposure.

    Science.gov (United States)

    Chin-Pampillo, Juan Salvador; Masís-Mora, Mario; Ruiz-Hidalgo, Karla; Carazo-Rojas, Elizabeth; Rodríguez-Rodríguez, Carlos E

    2016-08-01

    Biomixtures constitute the biologically active part of biopurification systems (BPS), which are used to treat pesticide-containing wastewater. The aim of this work was to determine whether co-application of chlorpyrifos (CLP) affects the removal of carbofuran (CFN) (both insecticide/nematicides) in a coconut fiber-compost-soil biomixture (FCS biomixture), after aging or previous exposure to CFN. Removal of CFN and two of its transformation products (3-hydroxycarbofuran and 3-ketocarbofuran) was enhanced in pre-exposed biomixtures in comparison to aged biomixtures. The co-application of CLP did not affect CFN removal, which suggests that CLP does not inhibit microbial populations in charge of CFN transformation. Contrary to the removal behavior, mineralization of radiolabeled (14)C-pesticides showed higher mineralization rates of CFN in aged biomixtures (with respect to freshly prepared or pre-exposed biomixtures). In the case of CLP, mineralization was favored in freshly prepared biomixtures, which could be ascribed to high sorption during aging and microbial inhibition by CFN in pre-exposure. Regardless of removal and mineralization results, toxicological assays revealed a steep decrease in the acute toxicity of the matrix on the microcrustacean Daphnia magna (over 97%) after 8days of treatment of individual pesticides or the mixture CFN/CLP. Results suggest that FCS biomixtures are suitable to be used in BPS for the treatment of wastewater in fields where both pesticides are employed. PMID:27521950

  5. Chlorpyrifos induces NLRP3 inflammasome and pyroptosis/apoptosis via mitochondrial oxidative stress in human keratinocyte HaCaT cells.

    Science.gov (United States)

    Jang, Yoonjeong; Lee, Ah Young; Jeong, Sang-Hee; Park, Kyung-Hun; Paik, Min-Kyoung; Cho, Nam-Joon; Kim, Ji-Eun; Cho, Myung-Haing

    2015-12-01

    Chlorpyrifos (CPF) has been widely used around the world as a pesticide for both agricultural and residential application. Although various studies have reported toxicity and health-related effects from CPF exposure, the molecular mechanism of CPF toxicity to skin has not been well-characterized. The present study determined the potential mechanism involved in skin toxicity of CPF using the HaCaT human skin keratinocyte cell line. After treating to HaCaT cells, CPF triggered reactive oxygen species (ROS) generation and mitochondrial oxidative stress. We focused on NLRP3 inflammasome, known to induce innate immune response. We used mitochondrial ROS (mROS) scavenger mitoTEMPO to demonstrate a role for mROS in NLRP3 inflammasome and programmed cell death induced by CPF. Our results showed that CPF provoked NLRP3 inflammasome and pyroptosis/apoptosis via an increase of mROS in HaCaT cells. This study proposes that CPF induces innate immune response and skin inflammation through activating the NLRP3 inflammasome in skin epithelial cells. CPF may lead to cutaneous disease conditions and antioxidants could be proposed for therapy against skin exposure to CPF. PMID:26435000

  6. Alterations in juvenile diploid and triploid African catfish skin gelatin yield and amino acid composition: Effects of chlorpyrifos and butachlor exposures.

    Science.gov (United States)

    Karami, Ali; Karbalaei, Samaneh; Zad Bagher, Fariba; Ismail, Amin; Simpson, Stuart L; Courtenay, Simon C

    2016-08-01

    Skin is a major by-product of the fisheries and aquaculture industries and is a valuable source of gelatin. This study examined the effect of triploidization on gelatin yield and proximate composition of the skin of African catfish (Clarias gariepinus). We further investigated the effects of two commonly used pesticides, chlorpyrifos (CPF) and butachlor (BUC), on the skin gelatin yield and amino acid composition in juvenile full-sibling diploid and triploid African catfish. In two separate experiments, diploid and triploid C. gariepinus were exposed for 21 days to graded CPF [mean measured: 10, 16, or 31 μg/L] or BUC concentrations [Mean measured: 22, 44, or 60 μg/L]. No differences in skin gelatin yield, amino acid or proximate compositions were observed between diploid and triploid control groups. None of the pesticide treatments affected the measured parameters in diploid fish. In triploids, however, gelatin yield was affected by CPF treatments while amino acid composition remained unchanged. Butachlor treatments did not alter any of the measured variables in triploid fish. To our knowledge, this study is the first to investigate changes in the skin gelatin yield and amino acid composition in any animal as a response to polyploidization and/or contaminant exposure.

  7. Effects of melatonin on changes in cognitive performances and brain malondialdehyde concentration induced by sub-chronic co-administration of chlorpyrifos and cypermethrin in male Wister rats

    Institute of Scientific and Technical Information of China (English)

    Idris Sherifat Banke; Ambali Suleiman Folorunsho; Bisalla Mohammed; Suleiman Mohammed Musa; Onukak Charles; Ayo Joseph Olusegun

    2014-01-01

    Objective: To evaluate the ameliorative effect of melatonin on sub-chronic chlorpyrifos (CPF) and cypermethrin (CYP)-evoked cognitive changes in male Wistar rats. Methods:Fifty adult male Wistar rats, divided into five groups of ten rats each, were used for the study. Groups 1 and II were given distilled water and soya oil (2 mL/kg) respectively. Group III was administered with melatonin at 0.5 mg/kg only. Group IV was administered with CPF [7.96 mg/kg (1/10th LD50)] and CYP [29.6 mg/kg (1/10th LD50)] , and Group V was administered with CPF [7.96 mg/kg (1/10th LD50)] and CYP [29.6 mg/kg (1/10th LD50)] 30 min after melatonin (0.5 mg/kg). The regimens were administered by gavage once daily for 12 weeks. Thereafter, cognitive performances were determined and the brain was evaluated for malonaldehyde concentration. Results: CPF and CYP induced cognitive deficits and increased brain malonaldehyde concentration, which were all ameliorated by melatonin.Conclusion: Cognitive deficits elicited by CPF and CYP was mitigated by melatonin due to its antioxidant property.

  8. Apolipoprotein E (APOE) genotype and the pesticide chlorpyrifos modulate attention, motivation and impulsivity in female mice in the 5-choice serial reaction time task.

    Science.gov (United States)

    Peris-Sampedro, Fiona; Reverte, Ingrid; Basaure, Pia; Cabré, Maria; Domingo, José L; Colomina, Maria Teresa

    2016-06-01

    Organophosphate pesticides - and chlorpyrifos (CPF) in particular - contribute to a wide range of neurobehavioural disorders. Most experimental research focuses on learning and memory processes, while other behaviours remain understudied. The isoforms of the human apolipoprotein E (apoE) confer different cognitive skills on their carriers, but data on this topic are still limited. The current study was performed to assess whether the APOE genotypic variability differently modulates the effects of CPF on attentional performance, inhibitory control and motivation. Human apoE targeted replacement adult female mice (apoE2, apoE3 and apoE4) were trained to stably perform the 5-choice serial reaction time task (5-CSRTT). Animals were then subjected to daily dietary CPF (3.75 mg/kg body weight) for 4 weeks. After CPF exposure, we established a 4-week CPF-free period to assess recovery. All individuals acquired the task, apoE2 mice showed enhanced learning, while apoE4 mice displayed increased premature and perseverative responding. This genotype-dependent lack of inhibitory control was reversed by CPF. Overall, the pesticide induced protracted impairments in sustained attention and motivation, and it reduced anticipatory responding. ApoE3 mice exhibited delayed attentional disruptions throughout the wash-out period. Taken together, these findings provide notable evidence on the emergence of CPF-related attentional and motivational deficits. PMID:27106138

  9. Effects of Single and Co-Exposure of Cu and Chlorpyrifos on the Toxicity of Earthworm%铜﹑毒死蜱单一与复合暴露对蚯蚓的毒性作用

    Institute of Scientific and Technical Information of China (English)

    徐冬梅; 王彦华; 王楠; 饶桂维

    2015-01-01

    Combined pollution of heavy metal and pesticide had posed a serious threat to soil ecology and human living environment. As two common types of pollutants in soil environment, the environmental effects of combined pollution of Cu and chlorpyrifos are worth for attention. The acute lethal effects and avoiding behavior of single and co-exposure of Cu and chlorpyrifos on earthworms were analyzed by using the methods of standard OECD filter paper test and artificial soil test. Results showed that the LC50,48 h and LC50,14 d of the acute toxicity of Cu on earthworm in filter paper test and in artificial soil test were 2. 23 μg•cm-2 and 496. 05 mg•kg-1 , respectively. The LC50,48 h and LC50,14 dof the acute toxicity of chlorpyrifos on earthworm in filter paper test and in artificial soil test were 5. 94 μg•cm-2 and 186. 07 mg•kg-1 , respectively. In filter paper test and artificial soil test, the joint acute toxicity of Cu and chlorpyrifos showed an additive effect while the concentration was 1:1. The type of combined effects of co-exposure of Cu and chlorpyrifos was synergistic effect and antagonistic effect in filter paper test and artificial soil test, respectively, while the toxicity was 1:1. The results of avoidance behavior test showed that the joint effect of Cu and chlorpyrifos on the avoidance behavior of earthworms was antagonistic.%土壤环境中重金属-农药复合污染已经对土壤生态和人类生存环境构成严重威胁.其中重金属铜和有机磷农药毒死蜱作为土壤环境中两类常见的污染物,其复合污染的环境效应值得关注.本文采用OECD标准滤纸接触法﹑人工土壤法研究了铜-毒死蜱单一及复合暴露对蚯蚓急性致死作用及回避行为的影响.结果表明,滤纸法和人工土壤法Cu对蚯蚓急性毒性的48 h-LC50和14 d-LC50分别为2.23μg•cm-2和496.05 mg•kg-1;而毒死蜱对蚯蚓急性毒性的48 h-LC50和14 d-LC50分别为5.94μg•cm-2和186.07 mg•kg-1.滤

  10. Survey of organophosphate resistance and an Ala216Ser substitution of acetylcholinesterase-1 gene associated with chlorpyrifos resistance in Apolygus lucorum (Meyer-Dür) collected from the transgenic Bt cotton fields in China.

    Science.gov (United States)

    Zhen, Congai; Miao, Ling; Liang, Pei; Gao, Xiwu

    2016-09-01

    The mirid bug is frequently controlled by the application of organophosphorus insecticides in the transgenic Bt cotton field of China. A topical bioassay method was performed to evaluate the toxicities of chlorpyrifos and malathion towards field-collected Chinese populations of Apolygus lucorum from transgenic Bt cotton fields. For chlorpyrifos, the resistance ratios ranged from 0.8 to 9.4-fold compared to a susceptible strain. For malathion, the resistance levels relative to the susceptible strain ranged from 1.2 to 14.4-fold. Compared to a susceptible strain, the Cangzhou population from Hebei province showed the highest resistance ratios towards these insecticides. A comparison of the detoxifying and target enzyme activities between the Cangzhou population and a susceptible strain revealed that altered acetylcholinesterase possibly account for the chlorpyrifos and malathion resistance in the Cangzhou population. Two acetylcholinesterase (AChE-encoding) genes (designated Alace1 and Alace2) from the green mirid bug (A. lucorum) were identified. The Alace1 and Alace2 genes encoded 597 and 645 amino acids, respectively. Both AChE proteins had conserved motifs including a catalytic triad, a choline-binding site, and an acyl pocket. Quantitative real-time PCR analysis showed that Alace1 had a much higher transcriptional level than Alace2, for the expression profiles of both spatial and time distributions. One amino acid substitution, Ala216Ser in Alace1, was found in the Cangzhou population. These results suggest that the mutation Ala216Ser should be most likely involved in organophosphorus resistance in A. lucorum. PMID:27521910

  11. 阿维菌素与毒死蜱对小菜蛾联合毒力的生物测定%Co-toxicity of Abamectin and Chlorpyrifos to the Diamondback Moth Plutella xylostella (Lepidoptera: Plutellidae) Using Bioassay

    Institute of Scientific and Technical Information of China (English)

    魏书军; 聂秀东; 石宝才; 顾耘; 康总江; 王泽华; 宫亚军

    2012-01-01

    [方法]小菜蛾是十字花科蔬菜上危害最为严重的害虫之一.采用浸液法研究了阿维菌素与毒死蜱联合混配对小菜蛾的毒力作用.[结果]结果表明:2种药剂单用时阿维菌素毒力高于毒死蜱,24 h时阿维菌素和毒死蜱的LC50值分别为380.6794、2,274.0142 mg/L.24 h内两药剂混用表现为相加作用.阿维菌素与毒死蜱的比例为1∶2.22时,48、72 h后的共毒系数可高达983和998,均表现为增效作用.[结论]随着时间的延长,2种药剂混配后表现为较强的增效作用.%[Methods] The diamondback moth Plutella xylostella(Lepidoptem: Yponomeutidae) is one of the most serious pests of cruciferous vegetables. Here, the co-toxicity of abamectin and chlorpyrifos were tested using leaf dipping method. [Results] The results showed that the toxicity of abamectin is higher than chlorpyrifos when tested individually: with LC50, values of abamectin and chlorpyrifos are 380.6794 and 2,274.0142 mg/L respectively after 24 h, the two pesticides showed an addition of toxicity within 24 h. After 48 and 72 h, two pesticides showed an enhanced toxicity when the ratio of abamectin and chlorpyrifos is 1:2.22, the co-toxicity coefficient reached to 983(48 h) and 998(72 h). [Conclusions] The combination of the two pesticides shows enhanced toxicity with the increase of treatment time.

  12. Study on the treatment of chlorpyrifos wastewater by ultrasonic electro-coagulation and degradation pathway analysis%超声-电凝聚技术处理毒死蜱废水研究及降解途径分析

    Institute of Scientific and Technical Information of China (English)

    钱佳燕; 王玲; 薛建军; 蔡燕华; 周凝; 黄明喜

    2012-01-01

    According to the disadvantages of chlorpyrifos wastewater such as serious pollution 'and poor biodegradability, the treatment of chlorpyrifos wastewater by ultrasonic electro-coagulation was studied. In this research work, the effects of various parameters were investigated including voltage, ultrasonic power, initial organic phosphorus concentration and flowing rate. The energy consumption of removing chlorpyrifos by ultrasonic electro-coagulation method was discussed. The possible oxidative degradation pathway of chlorpyrifos in, wastewater was also derived. The results showed that for the waste water with organic phosphorus concentration of 10 mg · L-1, when the flowing rate was 250mL·min-1, the optimum voltage was 9V and ultrasonic power was 80W. At optimum condition, the removal efficiency of organic phosphorus and CODcr was 99.84%, 95.44% after 15min, respectively.%针对毒死蜱废水污染严重、可生化性差的特点,本实验研究了超声-电凝聚方法处理毒死蜱废水的效果.通过单因素实验探讨了电压、超声功率、原水初始有机磷浓度和流速等因素对超声-电凝聚法去除有机磷及CODCr效果的影响,并进行了能耗分析及毒死蜱降解途径分析.结果表明:最佳工艺条件为电压9V,超声功率80W、原水初始有机磷浓度10mg·L-1、流速250mL·min-1.在最佳条件下,电解15min后,有机磷的去除率达到99.84%,CODCr的去除率达到95.44%.

  13. Erythrocyte osmotic fragility and lipid peroxidation following chronic co-exposure of rats to chlorpyrifos and deltamethrin, and the beneficial effect of alpha-lipoic acid

    Directory of Open Access Journals (Sweden)

    Chidiebere Uchendu

    2014-01-01

    Full Text Available The present study aimed to evaluate the effect of chronic co-exposure to chlorpyrifos (CPF and deltamethrin (DLT on erythrocyte osmotic fragility, lipid peroxidation and the ameliorative effect of alpha-lipoic acid (ALA on erythrocyte fragility. Thirty-six male Wistar rats divided into six groups of six rats each were used for the study. Groups I (S/oil and II (ALA were given soya oil (2 ml/kg and ALA (60 mg/kg, respectively. Rats in group III (DLT and IV (CPF were exposed to DLT (6.25 mg/kg and CPF (4.75 mg/kg (1/20th of the previously determined LD50 of 125 mg/kg and 95 mg/kg, respectively, over a period of 48 h. Rats in group V (CPF + DLT were co-exposed to CPF (4.75 mg/kg and DLT (6.25 mg/kg, while those in group VI (ALA + CPF + DLT were pretreated with ALA (60 mg/kg and then co-exposed to CPF and DLT, 45 min later. The treatments were administered by gavage once daily for a period of 16 weeks. Blood collected at the end of the experimental period were analyzed for erythrocyte osmotic fragility and malondialdehyde (MDA concentration. The study showed that chronic co-exposure to CPF and DLT resulted in an increase in erythrocyte fragility and MDA concentration which were ameliorated by supplementation with alpha-lipoic acid. The study concluded that repeated co-exposure to CPF and DLT elevated erythrocyte fragility probably due to increased lipid peroxidation, and pretreatment with alpha-lipoic acid ameliorated these alterations.

  14. The toxicity of chlorpyrifos on the early life stage of zebrafish: a survey on the endpoints at development, locomotor behavior, oxidative stress and immunotoxicity.

    Science.gov (United States)

    Jin, Yuanxiang; Liu, Zhenzhen; Peng, Tao; Fu, Zhengwei

    2015-04-01

    Chlorpyrifos (CPF) is one of the most toxic pesticides in aquatic ecosystem, but its toxicity mechanisms to fish are still not fully understood. This study examined the toxicity targets of CPF in early life stage of zebrafish on the endpoints at developmental toxicity, neurotoxicity, oxidative stress and immunotoxicity. Firstly, CPF exposure decreased the body length, inhibited the hatchability and heart rate, and resulted in a number of morphological abnormalities, primarily spinal deformities (SD) and pericardial edema (PE), in larval zebrafish. Secondly, the free swimming activities and the swimming behaviors of the larvae in response to the stimulation of light-to-dark photoperiod transition were significantly influenced by the exposure to 100 and 300 μg/L CPF. In addition, the activity of acetylcholinesterase (AChE) and the transcription of some genes related to neurotoxicity were also influenced by CPF exposure. Thirdly, CPF exposure induced oxidative stress in the larval zebrafish. The malondialdehyde (MDA) levels increased and the glutathione (GSH) contents decreased significantly in a concentration-dependent manner after the exposure to CPF for 96 hours post fertilization (hpf). CPF affected not only the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione S-transferase (GST), but also the transcriptional levels of their respective genes. Finally, the mRNA levels of the main cytokines including tumor necrosis factor α (Tnfα), interferon (Ifn), interleukin-1 beta (Il-1β), interleukin 6 (Il6), complement factor 4 (C4) in the larvae increased significantly after the exposure to 100 or 300 μg/L CPF for 96 hpf, suggesting that the innate immune system disturbed by CPF in larvae. Taken together, our results suggested that CPF had the potential to cause developmental toxicity, behavior alterations, oxidative stress and immunotoxicity in the larval zebrafish.

  15. Ameliorative effect of vitamin C and E on hematological alterations induced by chlorpyrifos alone and in conjunction with fluoride in Wistar rats

    Directory of Open Access Journals (Sweden)

    Naseer A. Baba

    2013-06-01

    Full Text Available Objective: Chlorpyrifos (CPF is a common organophosphorus pesticide used worldwide for the management of agricultural and household pests. Similarly excessive fluoride (F ingestion is an important public health problem all over the world due to high fluoride content in groundwater. The present study aimed to investigate the alterations in hematological parameters by CPF alone and in conjunction with fluoride and their amelioration by vitamin C and E. Methods: The study was carried out in two phases; in the first phase toxicity was induced by toxicants and in the second phase ameliorative efficacy of vitamins was tested. Results: In the first phase, repeated oral administration of fluoride in drinking water at the dose of 1 and 10 mg/l caused increased monocyte and total leukocyte count (TLC. On the other hand, orally administered CPF (1 mg/kg resulted in decrease of packed cell volume (PCV with increase in TLC; in addition, granulocytes and monocytes were significantly increased. CPF at 10 mg/kg significantly decreased PCV and total erythrocyte count (TEC, whereas increase in TLC was observed. Co-administration of fluoride in drinking water (10 mg/l and CPF via oral gavage (10 mg/kg for 28 days resulted in decrease of hemoglobin (Hb, PCV, TEC whereas increase in TLC. The differential leukocyte count (DLC showed a decrease in lymphocyte values but an increase in granulocytes and monocytes. Conclusion: Simultaneous administration of with vitamin C and E along with CPF and fluoride ameliorated various hematological parameters, except TLC, granulocytes and monocytes, induced by co-exposure of CPF and fluoride in Wistar rats. [J Exp Integr Med 2013; 3(3.000: 213-218

  16. Ameliorative effect of vitamin E to mouse dams and their pups following exposure of mothers to chlorpyrifos during gestation and lactation periods.

    Science.gov (United States)

    Mansour, Sameeh Abdel-Kader; Gamet-Payrastre, Laurence

    2016-07-01

    Pesticides are omnipresent in environment, water, fruits, and vegetables and are considered as risk factors for human health. Consumers are mainly exposed to pesticides through diet, and the main question to be answered concerns the impact of such exposure on health. In this study, we developed a mouse model to mimic consumer exposure. During gestation and lactation periods, the experimental mouse dams (M) received one of the following treatments: (a) diet-free of pesticides; (b) diet enriched with chlorpyrifos (CPF; 44.0 μg kg(-1)); c) diet + oral vitamin E (vit. E; α-tocopherol; 200 mg/kg/mouse); and (d) diet enriched with CPF (44.0 μg/kg + oral vit. E (200 mg/kg/mouse). At weaning, pups (P) and dams were killed, and organs as well as blood samples were collected. Compared with control results, CPF induced alteration of measured parameters (e.g. organ weight, alkaline phosphatase, urea, malondialdehyde, superoxide dismutase, and cholinesterase) either in mouse dams or in their offspring. Also, CPF induced histological impairment in kidney, liver, and ovary. Administration of vit. E in conjunction with CPF clearly alleviated deviation of these parameters than those of control ones. In conclusion, a dietary exposure of mice during gestation and lactation to low dose of CPF led to significant changes in the mother but also in the weaned animals that have not been directly exposed to this pesticide. These biological and histological modifications could be reversed by an oral supplementation of vit. E. PMID:25234640

  17. Scale-Up and Demonstration of Fly Ash Oxonation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Larry LaBuz; Rui Afonso

    2005-06-30

    This is the fifth quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the fifth quarterly report and it refers to the time period from April-July 2005. (An additional month is included in this quarterly report as we have been in a data analyses mode and wanted to provide new data relative to the previous report). During this period, the project team has been reviewing and analyzing data from the onsite ozonation tests, as well as conducting additional laboratory ash and concrete tests. This report summarizes these activities including some preliminary results. No significant issues or concerns are identified.

  18. 漆酶/香草醛体系生物降解毒死蜱影响因素的研究%Factors affecting the biodegradation of chlorpyrifos by laccase/vanillin system

    Institute of Scientific and Technical Information of China (English)

    汪敏敏; 赵林果; 谢慧芳

    2012-01-01

    研究了漆酶介体体系对有机磷农药毒死蜱生物降解的效果及影响因素.通过对6种介体的试验比较,筛选了合适的介体.在试验条件下,1-羟基苯并三唑(HBT)和2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)(ABTS)对漆酶降解毒死蜱存在一定的抑制作用,紫脲酸(VA)和2,6-二甲氧基苯酚(2,6-DMP)对漆酶降解毒死蜱未起促进作用,而天然产物香草醛和愈创木酚可促进漆酶降解毒死蜱,香草醛的促进作用最为明显,选择香草醛作为漆酶介体体系中的介体.研究了漆酶/香草醛体系中,反应时间、漆酶初始酶活、pH、温度、介体投加量及投加方式、毒死蜱初始浓度等因素对毒死蜱生物降解效果的影响.结果表明,控制漆酶初始酶活为0.050 U/mL、pH为5.0、温度30℃,分2次投加香草醛(香草醛与毒死蜱初始值摩尔比分别为40和80)情况下,漆酶/香草醛体系即可在24 h内实现对25 mg/L毒死蜱的有效降解,降解率达98%.%The biodegradation of organophosphorus pesticide chlorpyrifos by laccase-mediator system (LMS) was studied and main factors that influencing the degradation efficiency were investigated. The performance of six mediators in LMS were tested, results showed that vanillin and guaigcol promoted the degradation of chlorrpy rifos by laccase, while 1-hydroxybenzotriazole (HBT) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) inhibited the degradation, violuric acid and 2,6-dimethoxyphenol had no obvious promotion. So vanillin was chcse:u as the mediator in LMS. The effect of reaction time,initial laccase activity,Ph,temperature,mediator dosage and the Initial chlorpyrifos concentration on chlorpyrifos biodegradation was investigated. The results showed that chlorp;yri£os could be well biodegraded by laccase/vanillin system. When laccase dosage was 0. 050 U/Ml, initial Ph was 5. 0 , temperature was 30 ℃ and adding vanillin for twice (molar rate of vanillin and

  19. β-环糊精及其衍生物与毒死蜱包合物杀灭蛴螬室内毒力测定%Indoor Toxicity Measurement of Chlorpyrifos withβ-Cyclodextrin and Its Derivatives to Grubs

    Institute of Scientific and Technical Information of China (English)

    苑东鹏; 王莹莹; 张斌; 刘林臣; 常志斌

    2014-01-01

    In order to study the feasibility of applying β-cyclodextrin (β-CD ) and its derivatives in high-efficient utilization of pesticides and environmental protection , the chlorpyrifos were mixed with β-CD、HP-β-CD、Me-β-CD, and their insecticidal effects to grubs were detected in the laboratory .The re-sults showed that the insecticidal efficiency of inclusion complexes ranked as chlorpyrifos -HP -β-CD, chlorpyrifos -Me-β-CD and chlorpyrifos-β-CD.%为研究β-环糊精(β-Cyclodextrin ,β-CD)及其衍生物在农药高效利用和环境保护等领域中应用的可行性,制备了β-CD、HD-β-CD、Me-β-CD与毒死蜱的包合物,并在室内进行了包合物毒杀蛴螬成虫试验。结果表明:包合物的杀虫效率从大到小依次为毒死蜱-HP-β-CD、毒死蜱-Me-β-CD、毒死蜱-β-CD。

  20. 围生期毒死蜱暴露致子代8周雄鼠睾丸组织的氧化损伤%Perinatal Exposure to Chlorpyrifos Induced Testicular Oxidative Damage in 8 Week Offspring Male Rat

    Institute of Scientific and Technical Information of China (English)

    徐肖倩; 张敏; 王学梅; 方鑫; 李海玲; 戴红; 肖瑞

    2015-01-01

    Chlorpyrifos is one of the largest used and saled organophosphorus pesticides throughout the world. To explore the testicular oxidative damage of 8 week offspring male rat induced by perinatal exposure to chlorpyrifos, the healthy pregnant Wistar female rats were exposed to chlorpyrifos of 0, 0.75, 1.35 and 2.70 mg•kg-1 by gavage during GD 6—PND21 d. Until the offspring male rat reached the age of 8 week, histopathological changes of left testis were observed. We also detected the level of MDA and the activity of GST, GSH-Px, and T-SOD in right tes-tis. The results showed that although no statistical significance were observed in body weight, the organ coefficient of testis and epididymis compared with control group, both of them showed a downward trend and of MDA showed an upward trend when the dose increased (P>0.05). The decrease in the activity of T-SOD of all dose groups, the increase of the activity of GSH-Px of 1.35 mg•kg-1 and 2.70 mg•kg-1 dose groups and the increase in activity of GST of 2.70 mg•kg-1 dose group were statistically significant (P0.05);而MDA呈升高趋势(P>0.05)。各组T-SOD和1.35、2.70 mg•kg-1剂量组GSH-Px活力的下降及2.70 mg•kg-1剂量组GST活力的升高均有统计学意义(P<0.05)。睾丸组织病理学检查结果可见2.70 mg•kg-1剂量组睾丸组织有明显的损伤,管腔中精液量减少,生精细胞脱落增多。上述研究结果提示母鼠于围生期暴露于毒死蜱,可通过氧化损伤诱导子代雄性大鼠睾丸的毒性作用。

  1. Biomarkers for the assessment of chlorpyrifos effects on earthworms and on soil functional parameters Biomarcadores para a avaliação dos efeitos de clorpirifós em minhocas e em parâmetros funcionais do solo

    Directory of Open Access Journals (Sweden)

    Lucas Piola

    2009-08-01

    Full Text Available The objective of this work was to evaluate the effects of chlorpyrifos on earthworms and on soil functional parameters. An integrated laboratory-field study was performed in a wheat field in Argentina, sprayed with chlorpyrifos at two recommended application rates (240 or 960 g ha-1 style='vertical-align:baseline'> a.i.. Laboratory tests included neutral red retention time, comet assay (single cell gel electrophoresis, and avoidance behavior, each using the earthworm Eisenia andrei exposed in soil collected 1 or 14 days after pesticide application, and the bait-lamina test. Field tests assessed organic matter breakdown using the litterbag and bait-lamina assays. Earthworm populations in the field were assessed using formalin application and hand-sorting. The neutral red retention time and comet assays were sensitive biomarkers to the effects of chlorpyrifos on the earthworm E. andrei; however, the earthworm avoidance test was not sufficiently robust to assess these effects. Feeding activity of soil biota, assessed by the bait lamina test, was significantly inhibited by chlorpyrifos after 97 days, but recovered by the 118th day of the test. Litterbag test showed no significant differences in comparison to controls. Earthworm abundance in the field was too low to adequately test the sensitivity of this assessment endpoint.O objetivo deste trabalho foi avaliar os efeitos do clorpirifós sobre as minhocas e sobre parâmetros funcionais do solo. Foi executado um estudo integrado campo-laboratório, em uma plantação de trigo na Argentina, onde foi aplicado clorpirifós em duas doses recomendadas (240 ou 960 g ha-1 a.i.. Os ensaios laboratoriais incluíram tempo de retenção do vermelho-neutro, ensaio cometa (eletroforese em gel de célula única e teste de fuga, cada um com a minhoca Eisenia andrei exposta aos solos coletados 1 e 14 dias após tratamentos, e teste com a lâmina-isca. Nos bioensaios de campo, avaliou-se a decomposição da mat

  2. Oxidative damage of mouse brain cells induced by pesticide chlorpyrifos%农药毒死蜱对小鼠脑细胞氧化损伤的研究

    Institute of Scientific and Technical Information of China (English)

    马萍; 焦铭; 尤会会; 赵静云; 杜娟; 罗清; 杨旭

    2013-01-01

    Chlorpyrifos is an efficient, low toxicity, broad-spectrum organophosphorus insecticide acaricide. This study aims at identifying the oxidative stress effects of chlorpyrifos on organisms. Kunming mice were orally administrated with chlorpyrifos daily for seven days at the concentration of 3 , 6 and 12 mg·kg-1 , respectively. The contents of reactive oxygen species (ROS) , glutathione (GSH) and malondialdehyde (MDA) in the brain homogenate and DNA-protein Crosslink (DPC) coefficients in the brain cells were measured to indicate the oxidative damages. The experimental results showed that the contents of ROS, MDA and DPC coefficients increased gradually while GSH content decreased with the increasing exposure dose, and all the biomarkers were in the exposure dose-response manner. When the exposure dose was at 6 mg·kg-1 , DPC coefficient was significantly higher than the control group (p < 0. 05 ) , and MDA contents had extremely significant differences (p < 0. 01). In the higher dose groups (12 mg·kg-1) , ROS content and DPC coefficient indicated significant differences compared with the control group (p <0.05) , and GSH and MDA contents had extremely significant differences (p <0.01 ). These experimental results demonstrated that chlorpyrifos can increase the oxidative stress and DNA-protein crosslinks in mouse brain at a higher dose.%毒死蜱是一种高效、低毒、广谱的有机磷杀虫杀螨剂.为研究其对生物体的氧化损伤,以昆明小鼠为受试体,毒死蜱按3、6和12 mg·kg-13个剂量水平灌胃染毒小鼠7d,以脑组织匀浆测定活性氧(Reactive oxygen species,ROS)、还原型谷胱甘肽(Glutathione,GSH)和丙二醛(Malondialdehyde,MDA)的含量,以脑细胞测定DNA-蛋白质交联(DNA-protein Crosslink,DPC)系数.实验结果表明,随着毒死蜱染毒剂量的升高,ROS和MDA含量及DPC系数逐渐上升,GSH含量逐渐降低,各指标呈一定的剂量-效应关系.染毒剂量为6 mg·kg-1时,与对

  3. 长三角地区毒死蜱水生生物基准研究%The Aquatic Organism Criteria for Chlorpyrifos in the Yangtze River Delta Region

    Institute of Scientific and Technical Information of China (English)

    王香兰; 周军英; 王蕾; 单正军; 葛峰; 张国祥

    2013-01-01

    [Methods] The toxicity data of 14 representative aquatic organisms was obtained through the toxicity tests. The aquatic organism criteria for chlorpyrifos in the Yangtze River Delta Region was derived by assessment factor, species sensitivity distributions and toxicity percentile rank respectively. [Results] The aquatic organism criteria of 0.013,0.112 and 0.021 μg/L was derived by assessment factor, species sensitivity distributions, and toxicity percentile rank. The differences of the criteria were compared. The reasons were analysed that the aquatic organism criteria for chlorpyrifos in the Yangtze River Delta Region was different from America, Canada, Australia and New Zealand. [Conclusions] The obtained results could provide scientific basis for the water quality criteria formulating.%[方法]通过毒性试验,得出毒死蜱对长三角地区14种代表性水生生物的毒性数据.分别采用评价因子法、物种敏感度分布法和毒性百分数排序法,推导长三角地区毒死蜱水生生物基准值.[结果]评价因子法、物种敏感度分布法和毒性百分数排序法得出的基准值分别是0.013、0.112、0.021 μg/L.比较了3种方法得出的基准值之间的差异,分析了长三角地区毒死蜱水生生物基准与美国、加拿大、澳大利亚和新西兰的基准值不同的原因.[结论]可为我国农药水质标准制订提供科学依据.

  4. 番茄、辣椒、茄子中甲基毒死蜱残留量测定%Determination of Chlorpyrifos-methyl Residues in Tomato,Hot Pepper and Eggplant

    Institute of Scientific and Technical Information of China (English)

    张征; 武中平

    2011-01-01

    采用高效液相色谱-二极管阵列检测器对番茄、辣椒和茄子中甲基毒死蜱残留量进行测定。样品用乙腈提取后,经Carb/NH2固相萃取小柱净化,用C8液相色谱柱、二极管阵列检测器,对甲基毒死蜱残留量的测定可取得满意的结果。该方法样品平均加标回收率为80.7%~92.4%,相对标准偏差为1.1%~4.6%;蔬菜中甲基毒死蜱检出下限为0.02mg/kg。%A high performance liquid chromatography method was presented for the determination of chlorpyrifos-methyl residues in tomato,hot pepper and egg plant.The chlorpyrifos-methyl residues in the samples were extracted into acetonitrile,cleaned up using a Carb/NH2 solid phase extraction column,separated on a C8 liquid chromatography column,and detected with a diode array detector(DAD).The average spike recoveries of the method across three spike levels were between 80.7% and 92.4%(n =6),with a relative standard deviation between 1.1% and 4.6%.The detection limit of the method were 0.02 mg/kg.

  5. Experimental hut evaluation of bednets treated with an organophosphate (chlorpyrifos-methyl or a pyrethroid (lambdacyhalothrin alone and in combination against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes

    Directory of Open Access Journals (Sweden)

    Corbel Vincent

    2005-05-01

    Full Text Available Abstract Background Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments. Methods Comparative studies of chlorpyrifos-methyl (CM, an organophosphate with low mammalian toxicity, and lambdacyhalothrin (L, a pyrethroid, were conducted in experimental huts in Côte d'Ivoire, West Africa. Anopheles gambiae and Culex quinquefasciatus mosquitoes from the area are resistant to pyrethroids and organophosphates (kdr and insensitive acetylcholinesterase Ace.1R. Several treatments and application rates on intact or holed nets were evaluated, including single treatments, mixtures, and differential wall/ceiling treatments. Results and Conclusion All of the treatments were effective in reducing blood feeding from sleepers under the nets and in killing both species of mosquito, despite the presence of the kdr and Ace.1R genes at high frequency. In most cases, the effects of the various treatments did not differ significantly. Five washes of the nets in soap solution did not reduce the impact of the insecticides on A. gambiae mortality, but did lead to an increase in blood feeding. The three combinations performed no differently from the single insecticide treatments, but the low dose mixture performed encouragingly well indicating that such combinations might be used for controlling insecticide resistant mosquitoes. Mortality of mosquitoes that carried both Ace.1R and Ace.1S genes did not differ significantly from mosquitoes that carried only Ace.1S genes on any of the treated nets, indicating that the Ace.1R allele does not confer effective resistance to chlorpyrifos-methyl under the realistic conditions of an experimental hut.

  6. Efecto del enriquecimiento con nutrientes en la degradación de clorpirifos, malatión y metil paratión Inorganic nutrients effect addition over the chlorpyrifos, malathion and methyl parathion degradation

    Directory of Open Access Journals (Sweden)

    S. A. Upegui

    2011-01-01

    Full Text Available Con el fin de evaluar el efecto del enriquecimiento con nutrientes (una sal de fósforo o un fertilizante comercial con N, P y K como alternativa para mejorar la capacidad de degradación de los microorganismos en una matriz sólida, contaminada con los pesticidas organofosforados: clorpirifos, malatión y metil paratión, se realizaron experimentos de cultivo bajo condiciones controladas de oscuridad, temperatura y humedad por 30 días. En todos los tratamientos hubo degradación de los pesticidas; sin embargo, en el tratamiento con fósforo los tiempos para degradar el clorpirifos y el metil paratión fueron mayores. La presencia de los pesticidas no generó efectos tóxicos detectables sobre la microflora en ninguno de los tratamientos evaluados. La actividad biológica de las matrices no presentó una relación directa con la capacidad de degradación.In order to evaluate the effect of inorganic nutrient addition (phosphorus or commercial fertilizer over the microbial degradation capacity present in a solid matrix contaminated with chlorpyrifos, malathion and methyl parathion, microcosms assays were held under controlled conditions of light, moisture and temperature for 30 days. Results showed that even though three treatments microorganisms were able to degrade the three organophosphorus pesticides, microorganisms of phosphorus-enrichment treatment were less efficient to degrade Chlorpyrifos and Methyl Parathion than microorganisms of Fertilizer-enrichment treatment. It was not observed a direct relation between mineralization and microbial pesticides degradation capacity. The microbial activity was not affected by the presence of organophosphorus pesticides.

  7. Developmental cholinotoxicants: nicotine and chlorpyrifos.

    OpenAIRE

    Slotkin, T A

    1999-01-01

    The stimulation of cholinergic receptors in target cells during a critical developmental period provides signals that influence cell replication and differentiation. Accordingly, environmental agents that promote cholinergic activity evoke neurodevelopmental damage because of the inappropriate timing or intensity of stimulation. Nicotine evokes mitotic arrest in brain cells possessing high concentrations of nicotinic cholinergic receptors. In addition, the cholinergic overstimulation programs...

  8. The synergistic toxicity of the multiple chemical mixtures: implications for risk assessment in the terrestrial environment.

    Science.gov (United States)

    Chen, Chen; Wang, Yanhua; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang

    2015-04-01

    The combined toxicity of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor) and a heavy metal (cadmium) has been examined with the earthworm acute toxicity test. Toxicological interactions of these chemicals in four, five, six, seven, and eight-component mixtures were studied using the combination-index (CI) equation method. In four-component and five-component mixtures, the synergistic effects predominated at lower effect levels, while the patterns of interactions found in six, seven, and eight-component mixtures displayed synergism. The λ-CY+IMI+BUT+ATR+CPF+PHO combination displayed the most strongly synergistic interaction, with CI values ranging from 0.09 to 0.15. The nature of the interaction changes with the effect level and the relevance of synergistic effects increase with the complexity of the mixture. The CI method was compared with the classical models of concentration addition (CA) and independent action (IA) and we found that the CI method could accurately predict the combined toxicity. The predicted synergism resulted from co-existence of the pesticides and the heavy metal especially at low effect levels may have important implications in risk assessment for the real terrestrial environment.

  9. 有机农药滴滴涕和毒死蜱生物降解机制的分子模拟研究%Biodegradation Mechanism of DDT and Chlorpyrifos Using Molecular Simulation

    Institute of Scientific and Technical Information of China (English)

    林玉珍; 曾光明; 张娱; 陈明; 蒋敏; 张嘉超; 鲁伦慧; 刘利锋

    2012-01-01

    为探索有机农药滴滴涕和毒死蜱相应降解酶的微观降解机制,用分子对接方法模拟了滴滴涕(DDT)与漆酶(laccase)、毒死蜱(chlorpyrifos)与有机磷水解酶(organophosphorus hydrolase)的相互作用,得到它们复合物结构的理论模型,根据打分函数最低原则筛选出的最佳构象打分函数分别为-103.134和-111.626,二次打分函数分别为-72.858和-80.261.并应用LPC/CSU server研究这些最佳构象的相互作用情况,结果表明,滴滴涕与漆酶之间以疏水作用数量最多,毒死蜱与有机磷水解酶以氢键和疏水作用数量最多.漆酶的Tyr224和有机磷水解酶的Arg254在催化过程中起到了重要作用.%In order to explore the microscopic degradation mechanism of organic pesticides degrading enzymes,we used molecular docking method to investigate the binding modes of DDT to laccase and chlorpyrifos to organophosphorus hydrolase,and obtained the corresponding complex structures.According to the principle of minimum scoring,the results showed that the MolDock scores were-103.134 and-111.626,re-rank scores were-72.858 and-80.261,respectively.And we used LPC/CSU server search the interactions between organic pesticides and their degrading enzymes.Our results showed that hydrophobic interaction was the strongest contacts in DDT-laccase complex,and both hydrogen bonds and hydrophobic interactions were the strongest contacts when chlorpyrifos-organophosphorus hydrolase complex.The amino acid residues Tyr224 in laccase and Arg254 in organophosphorus hydrolase were detected to play significant roles in catalytic processes.

  10. Difference of Chlorpyrifos Residue in Fruits of Various Apple Cultivars and Bagging Effect on the Residue%苹果果实中毒死蜱残留的品种间差异及套袋对毒死蜱残留的影响

    Institute of Scientific and Technical Information of China (English)

    陈振德; 陈建美; 韩明三; 王文娇; 曹委

    2011-01-01

    Apple is one of important fruits exported in China. The pesticide residue in apple fruit directly impacts the export trade of agricultural products and safety of consumer. Chlorpyrifos is one of organophosphorous pesticides permitted to be used in apple production. In order to evaluate the difference of chlorpyrifos residue in fruits of various apple cultivars and effects of fruit bagging on fruit chlorpyrifos residue, chlorpyrifos residue quantity in different tissues of fruit of various apple cultivars was determined with gas chromatography ( GC- FPD ). The results showed that there was a significant difference among apple cultivars in chlorpyrifos residue in the fruit, Red Fuji belonged to the cultivar with high pesticide residues, while Gala, Red General and 83-1-70-3 to the cultivars with low pesticide residues. Chlorpyrifos residues showed significant difference in different fruit tissues of apple, the final residue of pesticide in the pericarp was the highest, followed in the whole fruit, lowest in the pulp. Chlorpyrifos residue in apple fruit was significantly decreased with bagging. Regardless of the pesticide concentration applied, and sampling time, pesticide residue in bagged apple fruit reduced by 33% as compared with that in fruit without being bagged.%为探讨苹果果实中毒死蜱残留的品种间差异及套袋对其残留的影响作用,采用气相色谱法(GC-FPD),研究了不同品种苹果果实中毒死蜱的残留动态以及套袋对苹果果实不同部位中毒死蜱残留的影响.结果表明,毒死蜱在苹果果实中的残留量存在着明显的品种差异,其中红富士属于高农药残留的品种,而嘎拉、红将军和83-1-70-3则属于低农药残留的品种.毒死蜱在苹果果实不同部位中的残留量表现出明显差异,果皮是毒死蜱残留的主要部位,其次是全果,果肉中的残留最少.套袋明显减少了毒死蜱在苹果果实中的残留量,不论处理浓度和取样时间如何,套袋苹

  11. Pollution of Waterbody by Chlorpyrifos Used in Paddy Rice Field in Hilly Areas and Its Ecological Risk.%丘陵地区水稻田使用毒死蜱对水体的污染及其生态风险

    Institute of Scientific and Technical Information of China (English)

    吴长兴; 赵学平; 吴声敢; 陈丽萍; 王彦华; 王强; 吴珉

    2011-01-01

    选择丘陵地区的小规模水稻田作为试验地,调查毒死蜱在该区域水稻田中的使用时间和使用量,监测不同时期水稻田进出水中毒死蜱残留水平.结果显示,毒死蜱使用后水稻田出水中毒死蜱残留水平高于进水,最高达26.07μg.L-1.从河流引入的进水中也存在毒死蜱残留,最高达3.23μg·L-1,说明上游农田已经对河水产生了污染.毒死蜱对斑马鱼(Brachydanio rerio)、大型溞(Daphnia magna)和斜生栅列藻(Scenedesmus obliquus)的急性毒性测定结果分别为:斑马鱼,ρ(96h,LC50)为1.11mg·L-1;大型溞,ρ(48 h,EC50)为1.44μg·L-1;斜生栅列藻,ρ(72 h,EC50)为0.193 mg·L-1.根据欧盟急性毒性风险评价标准进行评估,结果表明毒死蜱对水稻田周边水体中鱼类和藻类为低风险,对大型溞为有风险.%A small scale field experiment in a hilly area was carried out to investigate dates and doses of chlorpyrifos sprayed in paddy fields during the rice growing season in that region, and residues of chlorpyrifos in irrigation and drainage waters of the paddy fields were measured at various rice growing periods. It was found that chlorpyrifos residue level was higher in the drainage water than in the irrigating water, and reached 26. 07 μg · L-1. The irrigation water diverted from rivers was also found to have chlorpyrifos residue, with the highest reaching as high as 3.23 μg · L-1, indicating that the river water had already been polluted by chlorpyrifo from its use in paddy fields in the river's upstream area. The acute toxicity p of chlorpyrifos was determined to be 1.11 mg · L- 1 (96 h-LC50 ) to zebrafish, 1.44 μg · L- 1 (48 h-EC50 ) to Daphnia magna and 0. 193 mg L-1 (72 h-EC50) to algae. According to the acute risk assessment criteria established in the European Union(EU) legislation, chlorpyrifos is determined to be low in risk to fish and algae, but is risky to Daphnia magna in the waterbodies around paddy fields.

  12. Sublethal effects of chlorantraniliprole and chlorpyrifos on the growth,development and fecundity of Spodoptera exigua%氯虫苯甲酰胺、毒死蜱亚致死剂量对甜菜夜蛾生长发育和繁殖力的影响

    Institute of Scientific and Technical Information of China (English)

    马冲; 路兴涛; 刘震; 马士仲; 张田田

    2012-01-01

    The toxicity of chlorantraniliprole and chlorpyrifos to Spodoptera exigua was determined using dipping-insect methods, and the sublethal effects of chlorantraniliprole and chlorpyrifos on the growth, development and fecundity of S. Exigua were studied. The results indicated that the toxicity of chlorantraniliprole was 665.61-time (LC50) higher than that of chlorpyrifos. The ratios of pupation, weight of pupae and emergence of S. Exigua were decreased with the increase of concentrations after treated with the two insecticides. After treated with LC10 ? LC30 ,LC50 of chlorantraniliprole, the ratios of pupation, weight of pupae and emergence were lower than those treated with chlorpyrifos, in which the weight of pupae treated with LC10、LC50 of chlorantraniliprole were significantly lower than those of chlorpyrifos, and the emergence of the insect treated with LC50 of chlorantraniliprole were significantly lower than with chlorpyrifos. After treated with the two insecticides, oviposition numbers of single female were decreased with the increase of concentrations, in which the oviposition numbers of the insect treated with chlorantraniliprole were all lower than with chlorpyrifos except with the LC50 dosage. However, the ratios of egg hatching and survival were 89. 56%—91. 62% and 69.06% —73. 38%, respectively, and the differences were not significantly, compared with the CK.%采用浸虫法测定了氯虫苯甲酰胺、毒死蜱对甜菜夜蛾4龄幼虫的毒力,并比较了亚致死剂量对甜菜夜蛾生长发育和繁殖力的影响.结果表明,氯虫苯甲酰胺对甜菜夜蛾4龄幼虫毒力明显高于毒死蜱,其毒力为毒死蜱的665.61倍(LC50);两药剂亚致死剂量处理甜菜夜蛾4龄幼虫后,随着处理浓度的升高其化蛹率、蛹重、羽化率逐渐下降,氯虫苯甲酰胺LC10、LC30、LC50剂量处理后甜菜夜蛾化蛹率、蛹重和羽化率均低于毒死蜱LC10、LC30、LC50处理,其中氯虫苯甲酰胺LG10、LC50剂量

  13. Accumulation and transformation of the chlorpyrifos metabolite 3,5,6-TCP in soil and plants%毒死蜱主要代谢物3,5,6-TCP在土壤、植物中的累积与转化

    Institute of Scientific and Technical Information of China (English)

    孙宝利; 陕红; 袁志华; 曾希柏

    2013-01-01

    By pot experiment and laboratory soil incubation experiment, the accumulation and transformation of 3,5,6-trichloro-2-pyridinol(3,5,6-TCP), the main metabolite of chlorpyrifos in plant and soil were monitored in order to investigate the accumulation process and its affecting factors of the metabolite of chlorpyrifos in plants and soils. The results showed that:(l)The accumulative amount of 3, 5,6-TCP in plant and soil reached the peak at the 7th day and 14th day, respectively, after chlorpyrifos applied by recommended dose; the degradation rate of 3,5,6-TCP in plant was faster than that in plant and the residue amount of 3,5,6-TCP in plant was undetectable 20 days later; (2) Physical properties of 5 kinds of soil has the decisive effects on the accumulated residue of 3,5,6-TCP and the accumulated value increased with the increasing of the application amount of chlorpyrifos and temperature, however, there were no relationship with the amount of fertilizer and humidity. The average accumulated value of 3,5,6-TCP in five kinds of soil was among 0.14-0. 21μg/g; (3)by continuous monitoring sealed soil sample and using characteristics of chromatographic retention time, it further proved that 3,5,6-TCP was the metabolite of chlorpyrifos and could further transform into 3,5,6-trichloro-2-methoxypyridin (TMP). The result also showed that the degradation way of chlorpyrifos was related to the microbial and its species which can make the safe degra dation of chlorpyrifos possible.%本研究应用盆栽试验和室内土壤培养试验,考察毒死蜱主要代谢物3,5,6-三氯-2-吡啶(简称3,5,6-TCP)在植物、土壤中的累积与转化,研究毒死蜱代谢产物累积量变过程及其影响因素.结果表明:(1)推荐剂量喷施毒死蜱的第7天和第14天,3,5,6-TCP在植物体和土壤中的累积量达到峰值,直到20 d后,植物体内几乎测不出3,5,6-TCP残留,而土壤中3,5,6-TCP残留量仍较高,其降解速度较慢.(2)3,5,6-TCP在5种土壤中的

  14. 可降解聚碳酸亚丙酯-毒死蜱微胶囊的制备及缓释性能评价%Preparation of degradable poly( propylene carbonate)-chlorpyrifos micocapsule and performance evaluation on its controlled release

    Institute of Scientific and Technical Information of China (English)

    孟锐; 刘双清; 朱锐; 周小毛; 柏连阳; 李晓刚

    2012-01-01

    以聚碳酸亚丙酯( PPC)为壁材,聚乙烯醇-1788( PVA-1788)为连续相稳定剂,采用乳化溶剂挥发法制备了包裹毒死蜱的可降解微胶囊.测定了PVA-1788的质量分数、PPC的质量浓度以及PPC与毒死蜱的质量比对微胶囊性能的影响.采用土壤悬浊拟环境实验法评价了PPC的降解性能;通过光学显微镜(OM)、扫描电子显微镜(SEM)、广角X射线衍射(W-XRD)、激光粒度分布仪和高效液相色谱(HPLC)等表征了PPC -毒死蜱微胶囊的性能,同时采用柱层析法探讨了其缓释性能.结果表明:PPC具有生物可降解性;PVA-1788质量分数、PPC质量浓度以及PPC与毒死蜱的质量比对微胶囊的性能有显著影响,当PVA-1788的质量分数为1.0%、PPC的质量浓度为110 mg/mL,PPC与毒死蜱的质量比为1∶2时,可获得球形规整、粒径较小、包封率与载药量较高的微胶囊,其平均粒径为7.3 μm,载药量为16.75%,包封率为89.34%.缓释性能研究结果表明,PPC微胶囊对毒死蜱具有明显的缓释效应,27 d的累积释药率达86.87%.%Degradable microcapsules of chlorpyrifos were prepared by emulsion solvent volatilization method using poly (propylene carbonate) (PPC) as wall material and poly vinyl alcohol-1788 (PVA-1788) as emulsifier. The effects of PVA-1788 concentration, PPC concentration and mass ratio of PPC and chlorpyrifos on the performance of microcapsules were investigated. The degradation performance of PPC was evaluated by simulated soil suspension environment experiment. The PPC-chlorpyrifos microcapsule was charactered by scanning electron microscope ( SEM) , optical microscope ( OM), wide-angle X-ray diffraction spectra (W-XRD) and high performance liquid chromatograph (HPLC), and performance of its controlled-release was studied by column chromatography. The results showed that PPC had a favorable biodegradation and all of the concentration of PVA-1788 and PPC and mass ratio of PPC and chlorpyrifos showed a

  15. Relación entre residuos de clorpirifos en leche y sangre de vacas Holstein y niveles séricos de estradiol y tiroxina - Chlorpyrifos residues in milk and blood in Holstein cows and their relation to estradiol and thyroxin serum levels

    Directory of Open Access Journals (Sweden)

    Morales Vallecilla, Carlos

    2010-01-01

    Full Text Available ResumenLos disruptores endocrinos son sustancias que interfieren con la síntesis, secreción, transporte, acción o eliminación hormonal. Algunos pesticidas son considerados disruptores endocrinos y su uso indiscriminado ha sido asociado con afecciones metabólicas y reproductivas. El insecticida organofosforado clorpirifos, ampliamente utilizado para el control de plagas de los pastos enzonas lecheras de Antioquia, Colombia, ha sido asociado con alteraciones en los niveles de hormonas tiroideas y estrógenos. La presente investigación usó la cromatografía de gases para detectar la presencia de residuos de clorpirifos en sangre y leche de vacas Holstein alimentadas con pasto tratado con clorpirifos, además se determinaron por radioinmunoanálisis, los valores sanguíneos detiroxina y 17ß estradiol en los animales el día previo a la entrada en las pasturas tratadas y durante los siguientes 30 días. Aunque la cromatografía gaseosa fue efectiva para detectar clorpirifos en leche y suero durante la estandarización, en ninguna de las muestras de leche y suero sanguíneo de los animales del estudio se detectaron residuos de Clorpirifos. No se halló además diferencia significativa en las concentraciones de tiroxina y estradiol a lo largo del tratamiento. Los hallazgos indican que el tratar pastos con clorpirifos según las indicaciones del fabricante, no ocasionó residuos detectables del insecticida en la sangre y la leche de vacas que lo consumen. Los resultados además podrían indicar que en las concentraciones y condiciones recomendadas por el fabricante, el clorpirifos no es un disruptor endocrino para el ganado bovino enpastoreo.SummaryEndocrine disruptors are compounds that affect synthesis, secretion, transport, action or elimination of hormones. Some pesticides are considered endocrine disruptors and their use has been associated with metabolic and reproductive disorders. The organophosphate insecticide chlorpyrifos, widely used

  16. Research progress on male reproductive toxicity induced by chlorpyrifos and its mechanism%毒死蜱致雄性生殖毒性及其机制的研究进展

    Institute of Scientific and Technical Information of China (English)

    徐肖倩; 戴红

    2013-01-01

    毒死蜱(chlorpyrifos,CPF)系有机磷农药(organophosphates,OPs),广泛应用于农业生产和居住环境.毒死蜱不仅具有急性毒性,其慢性毒性和潜在危害日益引起业界关注.有研究提示CPF为可疑的环境内分泌干扰物(EEDs),具有生殖发育毒性.CPF的雄性生殖毒性主要表现为组织病理学、精子质量、激素水平和睾丸标志酶活性等发生变化,提示可能机制以脂质过氧化损伤机制研究居多.本文就CPF的雄性生殖毒性及其可能机制进行综述.

  17. Determination of 3,5,6-trichloro-2-pyridinol, phoxim and chlorpyrifos-methyl in water samples using a new pretreatment method coupled with high-performance liquid chromatography.

    Science.gov (United States)

    Peng, Guilong; Lu, Ying; He, Qiang; Mmereki, Daniel; Zhou, Guangming; Chen, Junhua; Tang, Xiaohui

    2015-12-01

    A novel low-density solvent-based vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction with the solidification of floating organic droplet method coupled with high-performance liquid chromatography was developed for the determination of 3,5,6-trichloro-2-pyridinol, phoxim and chlorpyrifos-methyl in water samples. In this method, the addition of a surfactant could enhance the speed of the mass transfer from the sample solution into the extraction solvent. The extraction solvent could be dispersed into the aqueous by the vortex process. The main parameters affecting the extraction efficiency were investigated and the optimum conditions were established as follows: 80 μL 1-undecanol as extraction solvent, 0.2 mmol/L of Triton X-114 selected as the surfactant, the vortex time was fixed at 60 s with the vortex agitator set at 3000 rpm, the concentration of acetic acid in sample solution was 0.4% v/v and 1.0 g addition of NaCl. Under the optimum conditions, the enrichment factors were from 172 to 186 for the three analytes. The linear ranges were from 0.5 to 500 μg/L with a coefficient of determination (r(2) ) of between 0.9991 and 0.9995. Limits of detections were varied between 0.05 and 0.12 μg/L. The relative standard deviations (n = 6) ranged from 0.26 to 2.62%. PMID:26475036

  18. Intuitionistic implication without disjunction

    NARCIS (Netherlands)

    Renardel de Lavalette, Gerard R.; Hendriks, Alex; Jongh, Dick H.J. de

    2012-01-01

    We investigate fragments of intuitionistic propositional logic containing implication but not disjunction. These fragments are finite, but their size grows superexponentially with the number of generators. Exact models are used to characterize the fragments.

  19. 14C-丁草胺、14C-毒死蜱和14C-DDT在日本林蛙中的生物学行为%BEHAVIORS OF 14C-BUTACHLOR,14C-CHLORPYRIFOS AND 14C-DDT IN Rana japonica japonica Guenther

    Institute of Scientific and Technical Information of China (English)

    张奕强; 张海清; 钟创光; 赵小奎; 陈舜华

    2002-01-01

    用同位素示踪技术研究了14C-丁草胺、14C-毒死蜱和14C-DDT在日本林蛙(Rana japonica japonica Guenther)中的生物学行为.结果发现,14C-丁草胺、14C-毒死蜱和14C-DDT在24h后分布到青蛙的各个器官组织,并分别以胆囊、小肠、小肠为它们的特异性浓集器官.与胆囊或小肠的14C放射性活度比较,其它器官组织中的要小得多.14C-DDT在日本林蛙中较难降解,24h后DDT母体在肝和脂肪组织中占DDT代谢物的54.6%和88.4%.青蛙中的14C-丁草胺、14C-毒死蜱和14C-DDT可被丙酮提取,但三者之间以及在青蛙的器官之间有差异.%The research on the behaviors of 14C-butachlor, 14C-chlorpyrifos and 14C-DDT in the frog Rana japonica japonica Guenther was carried out. After administrated per os to the frogs in doses of 380,347,363 Bq/g, 14C-butachlor, 14C-chlorpyrifos and 14C-DDT, were distributed respectively to various organs within 24 h with specific accumulating organs as gallbladder, intestine and intestine, relevantly to the pesticides described. Compared to that in gallbladder and intestine, the radioactivity of many organs was extremely low, and this might due to the characters of the pesticides. Analysis of the metabolites of 14C-DDT in frog at 24th hr demonstrated that DDT was difficult to be degraded. Most 14C-butachlor, 14C-chlorpyrifos 14C-DDT in liver and fat or ovary of frog was extractable with acetone. However, there were some differences between the pesticides, and the organs as well. And 14C-butachlor, 14C-chlorpyrifos or 14C-DDT were better bound in liver than in fat.

  20. 林丹、毒死蜱对淡水藻类毒性效应的比较研究%Toxic effects of Lindane and Chlorpyrifos on freshwater algae

    Institute of Scientific and Technical Information of China (English)

    邓惜汝; 鲜啟鸣; 孙成

    2014-01-01

    有机氯和有机磷农药是全球应用最广泛的两大类农药,以有机氯农药林丹以及有机磷农药毒死蜱为研究对象,比较了它们对长江中下游常见的3种淡水藻类包括铜绿微囊藻(Microcystis aeruginosa)、普通小球藻(Chlorella vulgaris)和梅尼小环藻(Cyclotella meneghiniana)的毒性效应。通过藻类生长抑制试验测定了林丹和毒死蜱对藻类的毒性效应,结果表明,林丹和毒死蜱对3种藻的生长存在不同程度的抑制效应,且质量浓度越高,抑制效应越强,其中低质量浓度的毒死蜱对铜绿微囊藻和普通小球藻具有一定的促进作用。实验还获得了两种农药对3种不同藻类的急慢性毒性数据,以96 h生物量计,林丹对铜绿微囊藻的EC50=442μg·L-1,LOEC=120μg·L-1,NOEC=60μg·L-1,MATC=85μg·L-1;对普通小球藻的EC50=524μg·L-1, LOEC=128μg·L-1,NOEC=61μg·L-1,MATC=88μg·L-1;对梅尼小环藻的EC50=11849μg·L-1,LOEC=1295μg·L-1,NOEC=406μg·L-1,MATC=725μg·L-1。毒死蜱对铜绿微囊藻的EC50=2720μg·L-1,LOEC=1026μg·L-1,NOEC=615μg·L-1,MATC=794μg·L-1;对普通小球藻的EC50=5374μg·L-1,LOEC=1978μg·L-1,NOEC=1172μg·L-1,MATC=1522μg·L-1;对梅尼小环藻的EC50=11109μg·L-1,LOEC=2792μg·L-1,NOEC=1355μg·L-1,MATC=1945μg·L-1。结果表明,林丹和毒死蜱对3种藻的生长存在不同程度的抑制效应。毒性数据显示相比于梅尼小环藻,铜绿微囊藻和普通小球藻对两种农药更为敏感。%Organochlorine and organophosphorus pesticide are the most widely used pesticides in the world. In this study, the toxic effects of Lindane and Chlorpyrifo on three species of freshwater algae (Microcystis aeruginosa, Chlorella vulgaris, and Cyclotella meneghiniana) were investigated using the algal growth inhibition test. The acute and chronic toxicity data of these two pesticides on algae including 96 h-EC50, LOEC, NOEC and MATC

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

    Institute of Scientific and Technical Information of China (English)

    Shuyin Li; Liming Zou; Carry Pope

    2008-01-01

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

  2. SEQUENCE ANALYSIS OF THE ENZYME CYP3A IN SILVER CARP AND ITS EXPRESSION INHIBITION BY CHLORPYRIFOS%白鲢肝脏CYP3A序列分析及毒死蜱对其抑制作用研究

    Institute of Scientific and Technical Information of China (English)

    马军国; 李效宇

    2013-01-01

    CYP3A是I相解毒酶系CYP450家族中的重要成员,在肝脏解毒过程中发挥重要作用。首次克隆了白鲢肝脏CYP3A基因并研究了毒死蜱对该基因表达的影响。生物信息学分析预测结果表明,CYP3A基因编码513个氨基酸,其蛋白质分子量为58.8 ku,理论等电点为7.96。该蛋白是一个稳定蛋白且具有一定的亲水性。二级结构预测可知,CYP3A包含45.2%的α-螺旋、12.3%的延伸链、4.3%的β-折叠和38.2%的无规则卷曲,具有2个显著的跨膜结合区。急性毒性实验结果表明,毒死蜱对白鲢具有很高的毒性,其96h LC50为0.172 mg/L。另外,荧光定量PCR检测发现,毒死蜱对白鲢CYP3A基因表达有明显的抑制作用。%Cytochrome P450 (CYPs) enzymes are responsible for the metabolism of various kinds of endogenous and exogenous compounds in mammals. In fish, CYP3A plays an important role in the detoxification of xenobiotics. In the present study, a full-length sequence of CYP3A cDNA in silver carp was cloned and sequenced, and then a phylogenetic tree of CYP3A was constructed. Additionally, the acute toxicity of chlorpyrifos on silver carp and the effect of chlor-pyrifos on CYP3A expression were also evaluated in this study. The results of bioinformatics prediction revealed that the full CYP3A encoded a protein of 513 amino acids and the molecular weight of CYP3A protein was 58.8 ku and the isoelectric point was 7.96. This protein was stable and hydrophilic, and it had 45.2% of α-spin, 12.3% of extended strand, 4.3%ofβ-fold, 38.2%of random coil and two binding-domain of crossing-membrane. Meanwhile, the results of acute toxicity tests indicated that chlorpyrifos was highly toxic to silver carp and the 96h LC50 of chlorpyrifos on silver carp was 0.172 mg/L. Finally, the results of Q RT-PCR indicated that chlorpyrifos significantly down regulated the expression of CYP3A at mRNA level in the liver of silver carp.

  3. Detection, Quantification, and Microlocalisation of Targets of Pesticides Using Microchannel Plate Autoradiographic Imagers

    Directory of Open Access Journals (Sweden)

    Mabruka H. Tarhoni

    2011-10-01

    Full Text Available Organophosphorus (OP compounds are a diverse chemical group that includes nerve agents and pesticides. They share a common chemical signature that facilitates their binding and adduction of acetylcholinesterase (AChE within nerve synapses to induce cholinergic toxicity. However, this group diversity results in non-uniform binding and inactivation of other secondary protein targets, some of which may be adducted and protein activity influenced, even when only a relatively minor portion of tissue AChE is inhibited. The determination of individual OP protein binding targets has been hampered by the sensitivity of methods of detection and quantification of protein-pesticide adducts. We have overcome this limitation by the employment of a microchannel plate (MCP autoradiographic detector to monitor a radiolabelled OP tracer compound. We preincubated rat thymus tissue in vitro with the OP pesticides, azamethiphos-oxon, chlorfenvinphos-oxon, chlorpyrifos-oxon, diazinon-oxon, and malaoxon, and then subsequently radiolabelled the free OP binding sites remaining with 3H-diisopropylfluorophosphate (3H-DFP. Proteins adducted by OP pesticides were detected as a reduction in 3H-DFP radiolabelling after protein separation by one dimensional polyacrylamide gel electrophoresis and quantitative digital autoradiography using the MCP imager. Thymus tissue proteins of molecular weights ~28 kDa, 59 kDa, 66 kDa, and 82 kDa displayed responsiveness to adduction by this panel of pesticides. The 59 kDa protein target (previously putatively identified as carboxylesterase I was only significantly adducted by chlorfenvinphos-oxon (p < 0.001, chlorpyrifos-oxon (p < 0.0001, and diazinon-oxon (p < 0.01, the 66 kDa protein target (previously identified as serum albumin similarly only adducted by the same three pesticides (p < 0.0001, (p < 0.001, and (p < 0.01, and the 82 kDa protein target (previously identified as acyl peptide hydrolase only adducted by chlorpyrifos-oxon (p

  4. 设施番茄植株中百菌清和毒死蜱残留分析方法研究%Analytical Method for Determining Residues of Chlorothalonil and Chlorpyrifos in Greenhouse Tomato Plant

    Institute of Scientific and Technical Information of China (English)

    何岸飞; 周尊隆

    2011-01-01

    运用超声提取、氧化铝-硅胶组合填料层析净化、气相色谱-质谱联用(GC-MS)检测,建立了设施番茄植株根、茎、叶和果实中同时测定百菌清和毒死蜱含量的分析方法。针对设施番茄植株叶绿素含量高的特点,优化了层析柱填料和洗脱溶剂配比,并研究了两种农药在层析柱中的洗脱规律。结果表明,在番茄根、茎、叶和果实中,百菌清平均回收率分别为95.9%、98.2%、86.2%和98.1%,毒死蜱的平均回收率分别为105.4%、995%、97.0%和98.0%。百菌清和毒死蜱的最低检测限分别为0.028 mg/kg和0.033 mg/kg。对比色素对两种农药在层析柱上洗脱的影响发现,大量叶绿素降低了百菌清的回收率。%Analytical method was developed with the purpose to determine residues of two commonly used insecticides, I.e, Chlorothalonil and Chlorpyrifos, in tomato plants grown in greenhouse, which involved the application of ultrasonic extraction, chromatographic purification with mixed fillings of alumina and silica gel and GC-MS detection. Considering high level of chlorophyll in tomato plants, elution of the two pesticides through chromatographic columns was optimized in terms of chromatographic fillings and elution solvents. As a result, average recoveries of chlorothalonil and chloropyrifos in tomato leaves, roots, stems and fruits respectively were obtained. By comparing the effects of chlorophyll on elution of two pesticides, the authors found that high chlorophyll in the tomato plants caused reduction of recovery of chlorothalonil.

  5. Inter-compartmental transport of organophosphate and pyrethroid pesticides in South China: Implications for a regional risk assessment

    International Nuclear Information System (INIS)

    The dynamic flux of an organophosphate and four pyrethroid pesticides was determined in an air-(soil)-water-sediment system based on monitoring data from Guangzhou, China. The total air–water flux, including air–water gaseous exchange and atmospheric deposition, showed deposition from air to water for chlorpyrifos, bifenthrin and cypermethrin, but volatilization for lambda-cyhalothrin and permethrin. The transport of the pesticides from overlying water to sediment suggested that sediment acted as a sink for the pesticides. Additionally, distinct annual atmospheric depositional fluxes between legacy and current-use pesticides suggested the role of consumer usage in their transport throughout the system. Finally, pesticide toxicity was estimated from annual air–water-sediment flux within an urban stream in Guangzhou. A dynamic flux-based risk assessment indicated that inter-compartmental transport of chlorpyrifos decreased its atmospheric exposure, but had little influence on its aquatic toxicity. Instead, water-to-sediment transport of pyrethroids increased their sediment toxicity, which was supported by previously reported toxicity data. - Highlights: • Transport fluxes of chlorpyrifos and pyrethroids were assessed in Guangzhou, China. • Sediment acted as a sink for chlorpyrifos and pyrethroids. • Air-to-water transport decreased the exposure risk of atmospheric chlorpyrifos. • Dynamic transport might increase the risk of pyrethroids in air and sediment. • Flux-based pesticide concentrations provide a way to estimate sediment toxicity. - Regional risk assessment could be improved by integrating dynamic flux information derived from inter-compartmental models

  6. Effects of Chlorpyrifos on Food Utilization and Detoxifying Enzymes and Acetylcholinesterase of Lymantria dispar%毒死蜱对舞毒蛾食物利用和解毒酶及AChE活性的影响

    Institute of Scientific and Technical Information of China (English)

    李慧; 严善春; 王志英; 葛士林; 曹传旺

    2011-01-01

    采用质量法和酶活性测定法研究了毒死蜱对舞毒蛾(Lymantria dispar)3龄幼虫食物利用的影响,并测定了其毒力及解毒酶、乙酰胆碱酯酶(AChE)的活性.用亚致死浓度(1.5 mg·L-1)毒死蜱处理小黑杨叶片,饲喂舞毒蛾3龄幼虫,其幼虫生长率(RGR)、食物利用率(ECI)和食物转化率(ECD)均显著低于对照,而近似消化率(AD)显著高于对照,相对取食量(RCR)处理和对照间差异不显著.毒死蜱对舞毒蛾幼虫24 h致死中浓度(LC50)为5.86 mg·L-1,其毒力低于三氟氯氰菊酯而高于氧化乐果.毒死蜱对舞毒蛾3龄幼虫体内羧酸酯酶(CarE)、谷胱甘肽S-转移酶(GSTs)和AChE均有抑制作用,抑制程度为CarE>AChE>GSTs.毒死蜱通过影响舞毒蛾食物利用和抑制酶活性而表现出杀虫活性,为一种有效防治舞毒蛾的有机磷杀虫剂.%The effects of sublethal dose of chlorpyrifos (CPF) on food utilization of gypsy moth, Lymantria dispar,as well as CPF toxicity and enzyme activities of carboxylesterase ( CarE ), glutathione S-transferases (GSTs) and acetylcholinesterase (AChE) were evaluated in the 3rd-instar gypsy moth larvae using gravimetric method and measuring enzyme activities. Relative growth rate (RGR), efficiency of the conversion of ingested food (ECI) and efficiency of the conversion of digested food (ECD) of 3rd-instar larvae fed on poplar leaves treated by sublethal concentration of CPF were significantly lower than thosc fed on normal polar leaves. However, approximate digestibility (AD) of the treatment was significantly higher than that of control. The relative consumption rate (RCR) of the treatment and control groups were not significantly different. The 24 h LC50 of CPF to the gypsy moth 3rd-instar larvae was 5.86 mg · L-1, which was higher than that of omethoate but lower than that of cyhalothrin. In vitro inhibition assay indicated that the activities of AChE, CarE and GSTs were inhibited by CPF depended on concentrations

  7. Acute Toxicity of Chlorpyrifos (CPF) to Crayfish (Procambarus clarkii) and the Histopathological Observation%毒死蜱(CPF)对克氏原螯虾的急性毒性及组织病理观察

    Institute of Scientific and Technical Information of China (English)

    丁正峰; 薛晖; 王晓丰; 唐建清

    2012-01-01

    采用静水生物测试法研究毒死蜱(CPF)对克氏原螯虾(Procambarus clarkii)的急性毒性效应及克氏原螯虾的组织病变情况并进行安全评价.设定0、2、10、20、40和80 μg·L-1 6个CPF浓度梯度进行急性暴露试验,结果表明,CPF浓度升高对克氏原螯虾产生较大毒性,24、48和96 h半致死浓度[ρ( LC5o)]分别为(28.24±2.81)、(19.50±2.03)和(13.13±1.70)μg·L-1-1ρ(LC5o)随着暴露时间延长呈显著下降趋势,符合双曲线衰减模型(r=0.999 9,P<0.000 1),安全浓度为(2.79±0.31) μg·L-1.组织病理观察发现,染毒虾心脏上皮细胞增生,心肌肌束间充满血淋巴细胞;神经细胞肿大,尼氏体溶解消失,细胞由多极形状变为圆形,神经纤维坏死并解体;肝胰腺小管收缩并充血,空泡增加;鳃组织空泡化,表面出现黑色素沉积,被多量血淋巴细胞浸润;肌肉纤维萎缩并溶解.%Acute toxicity of chlorpyrifos (CPF) on crayfish ( Procambarus clarkii) was studied with the static test method. In the acute exposure experiment, crayfish was exposed to CPF at the following concentrations, 0, 2, 10, 20, 40, and 80 u,g ? L-1. Results show that the higher the CPF concentration, the higher the toxicity to the crayfish. The 24, 48 and 96 h ρ(LC50) was (28.24 ±2. 81) , (19.50 ±2.03) and (13. 13 ± 1. 70) μg ? L-1 , respectively, and the safe concentration was (2.79 ± 0. 31 ) μg ? L-1. The lethal concentration of CPF to 50% of crayfish [ρ( LC50) ] decreased significant with time, which fitted a hyperbolic decay model ( r = 0. 999 9, P < 0. 000 1). Histopathological observation of the crayfish revealed that CPF pollution caused serious damages to its main organs, such as epithelial hyperplasia of the heart, impregnation of cardiac muscle bundles with haemocytes; swollen neorones, chromatolysis, change of cells from multipolar to round shape, necrosis and disorganization of nerve fibres, constriction and congestion of hepatopancreas tubules

  8. Effect of atrazine and chlorpyrifos on embryonic of common carp (Cyprinus carpio L%阿特拉津和毒死蜱对鲤胚胎发育的影响

    Institute of Scientific and Technical Information of China (English)

    韩英; 赵荣伟; 郝其睿; 姜旭阳; 张红

    2015-01-01

    研究旨在探讨不同浓度阿特拉津(Atrazine, ATR)、毒死蜱(Chlorpyrifos, CPF)及其混合物对鲤(Cyprinus carpio L.)胚胎发育、孵化率及抗氧化能力的影响。将鲤受精卵分别暴露在各自浓度为12.5、25、50、100、200μg·L-1的ATR、CPF及ATR-CPF 1��1混合液中,经96 h试验,观察发育形态,统计死亡率和畸形率,检测全鱼抗氧化能力。在暴露试验中,各处理组死亡率和畸形率随药物浓度增长呈上升趋势;初孵仔鱼体内SOD、GPx和CAT活性整体呈下降趋势。结果表明,阿特拉津和毒死蜱对鲤受精卵具有一定的致死、致畸效果,且两者生物毒性具有一定的叠加效应和协同作用,氧化胁迫是阿特拉津和毒死蜱对鲤发挥毒性作用的重要机制之一。%This study was aimed to explore the influence of different concentrations of atrazine (ATR), chlorpyrifos (CPF) and a mixture of them on embryonic development, hatchability and antioxidant capacity of common carp (Cyprinus carpio L.). The carp fertilized eggs was exposed to the concentrations of 12.5, 25, 50, 100, 200μg·L-1 ATR, CPF and ATR-CPF 1��1 mixture, respectively. After 96 h exposure, we observed their development of shape, and counted the death rate and aberration rate of the zygotes, detected antioxidant capacity of whole fish. In the exposure test, Mortality and malformation rate of treatment groups grow along with the drug concentration was on the rise;SOD, GPx and CAT activities in the newly hatched larvae of common carp as a whole were on the decline. The results indicated that ATR and CPF had some lethal and teratogenic effect on zygote of common carp, moreover, to a certain degree extent, the biotoxicity of these two toxic substances had additive effect and synergy, oxidative stress was one of the pivotal mechanism which ATR and CPF brought toxic effect to common carp.

  9. 毒死蜱有毒代谢物3,5,6-TCP在土壤中的吸附-解吸研究%Adsorption-desorption Behavior of Chlorpyrifos Toxic Metabolite 3,5,6-TCP on Soils

    Institute of Scientific and Technical Information of China (English)

    孙宝利; 曾希柏

    2011-01-01

    应用OECD 106批平衡方法,研究了毒死蜱的有毒代谢物3,5,6-TCP在6种典型土壤中的吸附-解吸行为.结果表明:Elovich方程、双常数方程和抛物线扩散方程能较好地拟合3,5,6-TCP在第四纪红土、黑土、黄壤和褐土中的吸附动力学过程,而对紫色土和潮沙土的拟合度较低(拟合相关系数小于0.85);应用Freundlich方程和线性方程拟合第四纪红土、黑土、黄壤和褐土的经验常数nfads均小于1(非线性吸附),而紫色土和潮沙土的nfads值则接近于1(线性吸附);3,5,6-TCP在6种土壤中解吸的滞后系数H值均大于1,即解吸速率大于吸附速率.6种土壤对3,5,6-TCP的吸附常数Kfads从1.37~6.74μg1-nf·mLnf·g-1,吸附系数Kd值从0.50~1.30mL·g-1,其中第四纪红土和黑土对其吸持力较强(Kd>1),因而更应注意环境安全;其他4种土壤的Kd值则均小于1,淋溶风险较大.%On the basis of the OECD Guideline 106, the batch equilibrium experiments were carried out in six kinds of soils to investigate adsorption and desorption processes of 3,5,6-TCP(3,5,6-trichloro-2-pyridinol), which were an ionizable organic compound and one kind of toxic metabolites of chlorpyrifos. The results showed that the adsorption kinetic behaviors of the 3,5,6-TCP in the quaternary red soil, black soil, yellow loam soil and brown soil were best described by the Elovich equation, Double Constant model and Parabolic diffusion model,while it could not be well described by above models( Correlation coefficient<0.85 ) in the purple and loam sand soils. Either linear or Freundlich sorption isotherm could describe the sorption behaviors of the 3,5,6-TCP in six kinds of soils with the values of the nfads < 1 (non-linear sorption ) in the quaternary red soil, black soil, yellow loam soil and brown soil and nfads ≈ 1 (linear sorption) in the purple and loam sand soil.The apparent adsorption-desorption hysteresis was found and the 3,5,6-TCP desorption rates in six

  10. Toxicity evaluation of chlorpyrifos and dimethoate to silkworm variety (Bombyx mori L. 9·Fu) in south China%毒死蜱和乐果对华南地区家蚕品种“9∙芙”的毒性评价

    Institute of Scientific and Technical Information of China (English)

    梅承芳; 张宝兰; 梁燕珍; 张宏涛; 曾国驱; 许玫英; 孙国萍

    2013-01-01

      “9·芙”(Bombyx mori L.9·Fu)作为华南地区饲养的主要家蚕种,考察广泛使用的有机磷农药毒死蜱和乐果对于“9·芙”蚕的毒性和安全性具有重要的经济意义和生态学意义。根据环保部《化学农药环境安全评价试验准则》的要求,首次采用浸叶法评价了w=97%毒死蜱和w=80.7%乐果对华南地区家蚕种“9·芙”(二龄起蚕)的急性毒性效应,根据其毒性范围进行分级,并系统观察了2种杀虫剂处理蚕后的中毒症状。结果表明:采用浸叶法测得的毒死蜱和乐果对“9·芙”蚕的96 h半数致死质量浓度(LC50)分别为2.0 mg·L-1和>400 mg·L-1,根据《化学农药环境安全评价试验准则》,毒死蜱和乐果对“9·芙”蚕分属高毒和低毒药剂。“9·芙”蚕对毒死蜱和乐果的敏感性与其他研究中不同地区蚕种的敏感性具有一定的相似性,且对2种杀虫剂的急性中毒症状具有一定的共性,为典型的有机磷农药中毒症状。蚕因毒死蜱中毒后的症状表现得更为迅速。由此可见,“9·芙”蚕可作为我国农药环境安全性评价中的供试蚕种;毒死蜱属于高毒农药,对于“9·芙”蚕可能存在高风险性,在实际施用中需严格控制施药方式和施药时期;乐果虽属低毒农药,但依然可引起“9·芙”蚕出现中毒效应,在实际施用中也需谨慎对待。%As the main silkworm variety in south China, Bombyx mori L. 9·Fu was used as the testing organism to evaluate the toxicities of the widely used organophosphorus pesticides: chlorpyrifos and dimethoate. Firstly, the acute toxicity effects of 97% chlorpyrifos and 80.7% dimethoate on Bombyx mori L. 9·Fu (the second instar larvae) were evaluated by using the leaf dipping method. The grade was compartmentalized according as toxicity scope and the toxic symptoms of silkworms were systematically observed after treatment with these two

  11. Implications of antisocial parents.

    Science.gov (United States)

    Torry, Zachary D; Billick, Stephen B

    2011-12-01

    Antisocial behavior is a socially maladaptive and harmful trait to possess. This can be especially injurious for a child who is raised by a parent with this personality structure. The pathology of antisocial behavior implies traits such as deceitfulness, irresponsibility, unreliability, and an incapability to feel guilt, remorse, or even love. This is damaging to a child's emotional, cognitive, and social development. Parents with this personality makeup can leave a child traumatized, empty, and incapable of forming meaningful personal relationships. Both genetic and environmental factors influence the development of antisocial behavior. Moreover, the child with a genetic predisposition to antisocial behavior who is raised with a parental style that triggers the genetic liability is at high risk for developing the same personality structure. Antisocial individuals are impulsive, irritable, and often have no concerns over their purported responsibilities. As a parent, this can lead to erratic discipline, neglectful parenting, and can undermine effective care giving. This paper will focus on the implications of parents with antisocial behavior and the impact that this behavior has on attachment as well as on the development of antisocial traits in children.

  12. Neutrino Experiments and Their Implications

    OpenAIRE

    Balantekin, A. B.

    2004-01-01

    Recent developments in solar, reactor, and accelerator neutrino physics are reviewed. Implications for neutrino physics, solar physics, nuclear two-body physics, and r-process nucleosynthesis are briefly discussed.

  13. Effects of sub-lethal concentrations of chlorpyrifos and isoprocarb on experimental population ofRhopalosiphum padi%亚致死浓度毒死蜱和异丙威对禾谷缢管蚜试验种群的影响

    Institute of Scientific and Technical Information of China (English)

    段辛乐; 乔宪凤; 陈茂华

    2015-01-01

    禾谷缢管蚜[Rhopalosiphum padi(Linnaeus)]是重要的小麦害虫,毒死蜱和异丙威作为有效防治禾谷缢管蚜的杀虫剂,可以在致死浓度下直接杀死禾谷缢管蚜,其亚致死浓度也可能会引起禾谷缢管蚜生理和行为的改变。为明确亚致死浓度的毒死蜱和异丙威对禾谷缢管蚜试验种群的影响,本研究采用浸叶法分别测定了毒死蜱和异丙威对禾谷缢管蚜成蚜的毒力;并以含0.1%吐温-80的蒸馏水为对照,利用生命表技术分别研究了毒死蜱亚致死浓度(C-LC20和 C-LC30)和异丙威亚致死浓度(I-LC20和 I-LC30)对禾谷缢管蚜 F0代和 F1代种群生长发育和繁殖的影响。结果表明, C-LC20、C-LC30、I-LC20和I-LC30处理后,禾谷缢管蚜F0代成蚜寿命分别缩短14.03%、36.04%、12.01%和26.86%,产蚜量分别下降20.55%、42.27%、17.13%和26.00%,均显著低于对照种群;与对照相比, C-LC20、C-LC30、I-LC20和I-LC30处理后,禾谷缢管蚜F1代种群的若虫期分别延长1.51 d、1.92 d、0.9 d和1.19 d,成蚜寿命分别缩短21.62%、33.68%、15.51%和23.14%,产蚜量分别降低21.81%、37.4%、14.51%和29.29%,且F1代种群的内禀增长率 rm、净生殖率R0、周限增长率λ以及总生殖率GRR都比对照降低,而F1代种群加倍时间Dt和平均世代周期T均延长。本研究结果显示,亚致死浓度的毒死蜱和异丙威能够降低禾谷缢管蚜种群的发育和繁殖速率,对禾谷缢管蚜种群具有明显的抑制作用。%AbstractRhopalosiphum padi(Linnaeus) is a devastating pest insect of wheat around the globe. Chlorpyrifos and isoprocarb have been widely used to controlR. padi in the field. Sub-lethal concentrates of chlorpyrifos and isoprocarb could affect the physiology and behavior ofR. padi. To evaluate the effects of sub-lethal concentrates of chlorpyrifos and isoprocarb on expe-rimental population ofR. padi, the leaf dipping method was used to test acute toxicity of chlorpyrifos and

  14. PARAOXONASE 1 (PON1) AS A GENETIC DETERMINANT OF SUSCEPTIBILITY TO ORGANOPHOSPHATE TOXICITY

    OpenAIRE

    Costa, Lucio G.; Giordano, Gennaro; Cole, Toby B.; Marsillach, Judit; Furlong, Clement E

    2012-01-01

    Paraoxonase (PON1) is an A-esterase capable of hydrolyzing the active metabolites (oxons) of a number of organophosphorus (OP) insecticides such as parathion, diazinon and chlorpyrifos. PON1 activity is highest in liver and in plasma. Human PON1 displays two polymorphisms in the coding region (Q192R and L55M) and several polymorphisms in the promoter and the 3’-UTR regions. The Q192R polymorphism imparts differential catalytic activity toward some OP substrates, while the polymorphism at posi...

  15. Control of San Jose Scale Nymphs, Diaspidiotus perniciosus (Comstock, on Almond and Apple Orchards with Pyriproxyfen, Phenoxycarb, Chlorpyrifos, and Mineral Oil Control de Ninfas de la Escama de San José, Diaspidiotus perniciosus (Comstock, en Almendros y Manzanos con Piriproxifen, Fenoxicarb, Clorpirifos y Aceite Mineral

    Directory of Open Access Journals (Sweden)

    Luis Sazo

    2008-09-01

    Full Text Available The effect of pyriproxyfen, phenoxycarb, chlorpyrifos, and mineral oil in the control of first generation nymphs of the San Jose scale (SJC, Diaspidiotus perniciosus (Comstock, in almond, Prunusdulcis (Mill. D.A. Webb, and apple, Malusdomestica Borkh. orchards was studied in the 2001-2002 season in central Chile. One and two sprays of pyriproxyfen 0.07% and phenoxycarb 0.05% were applied, the first at the beginning of the appearance of nymphs in early spring (biofix, and the other 15 days later, and were compared with one spray of chlorpyrifos 0.08% applied at the biofix. Also, one and two sprays of mineral oil 1% were evaluated, the first applied 7 days after the biofix, and the second 15 days after the first spray. Evaluations were done in the laboratory at the end of the dispersion of first generation nymphs, on December 27 and 28 for almonds and apples, respectively, counting the number of nymphs fixed per lineal meter of new twigs collected at infested sectors, percentage of infested apples, and the number of scales fixed per fruit. Results were subjected to ANOVA and Duncan multiple range tests. At low level infestation, one application of pyriproxyfen 0.07%, phenoxycarb 0.05%, or mineral oil 1% in spring reduced significantly (P≤0.05 the number of nymphs fixed per twig, at a level similar to that of a traditional treatment of chlorpyrifos 0.08%. However, at greater infestations, one spray of pyriproxyfen or mineral oil in spring was insufficient to control ESJ.En la temporada 2001-2002 se estudió el efecto de piriproxifen, fenoxicarb, clorpyrifos y aceite mineral en el control de las ninfas de la primera generación de la Escama de San José (ESJ, Diaspidiotus perniciosus (Comstock, en almendros, Prunusdulcis (Mill. D.A. Webb, y manzanos, Malusdomestica Borkh., en Chile central. Se hicieron una y dos aplicaciones de piriproxifen 0,07% y fenoxicarb 0,05%, la primera en el inicio del nacimiento de ninfas de primavera (biofix y la segunda

  16. THE ACTUAL IMPLICATIONS OF INFLATION

    Directory of Open Access Journals (Sweden)

    Murăriţa Ilie

    2011-12-01

    Full Text Available The authors have started from the idea that inflationary phenomenon is a companion, the cause and the effect of the globalization of poverty in the broader context of world economy globalization. Therefore, starting from a common definition of inflation, the first objective was to identify causal relationships that singularize contemporary inflationary process. After that, attention was focused on the implications of inflation in the current stage, bearing in mind that monetary financial theory and practice are operating with perfectly anticipated inflation or imperfectly anticipated inflation. Inflation has great implications on the long-term contracts and wage contracts.

  17. Mind, Matter and the Implicate Order The Implicate Order Revisited

    CERN Document Server

    Pylkkänen, Paavo T I

    2007-01-01

    Proposes that Bohm's alternative interpretation of quantum theory resolves the paradoxes such as Schrodinger's cat, and the EPR paradox. This work uses Bohm's concepts of "implicate order", "active information" and "soma-significance" as tools to tackle several well-known problems in the philosophy of mind.

  18. Educational Implications of the Bender.

    Science.gov (United States)

    Petti, Michael

    1988-01-01

    Examples of diagnostic formulations of the "Bender Visual-Motor Gestalt" are outlined and their instructional implications are delineated. The difficulties in paper and pencil copying of geometric designs focus primarily on: separation and overlapping of figures, repetition of design elements, pencil grip, visual perceptions, pattern reversals,…

  19. Astrosociological Implications of Astrobiology (Revisited)

    Science.gov (United States)

    Pass, Jim

    2010-01-01

    Supporters of astrobiology continue to organize the field around formalized associations and organizations under the guise of the so-called ``hard'' sciences (e.g., biology and the related physical/natural sciences). The so-called ``soft'' sciences-including sociology and the other social sciences, the behavioral sciences, and the humanities-remain largely separated from this dynamically growing field. However, as argued in this paper, space exploration involving the search for extraterrestrial life should be viewed as consisting of two interrelated parts (i.e., two sides of the same coin): astrobiology and astrosociology. Together, these two fields broadly combine the two major branches of science as they relate to the relationship between human life and alien life, as appropriate. Moreover, with a formalized system of collaboration, these two complimentary fields would also focus on the implications of their research to human beings as well as their cultures and social structures. By placing the astrosociological implications of astrobiology at a high enough priority, scientists interested in the search for alien life can augment their focus to include the social, cultural, and behavioral implications that were always associated with their work (yet previously overlooked or understated, and too often misunderstood). Recognition of the astrosociological implications expands our perception about alien life by creating a new emphasis on their ramifications to human life on Earth.

  20. Corporate Social Responsibility: Strategic Implications

    OpenAIRE

    Abagail McWilliams; Siegel, Donald S.; Patrick M. Wright

    2005-01-01

    We describe a variety of perspectives on corporate social responsibility (CSR), which we use to develop a framework for consideration of the strategic implications of CSR. Based on this framework, we propose an agenda for additional theoretical and empirical research on CSR. We then review the papers in this special issue and relate them to the proposed agenda.

  1. Policy Implications of Education Informatics

    Science.gov (United States)

    Carr, Jo Ann; O'Brien, Nancy P.

    2010-01-01

    Background/Context: This concluding article identifies the policy implications of education informatics and explores impacts of current copyright laws, legislative structures, publishing practices, and education organizations. Synthesizing the discussions in the preceding articles, this article highlights the importance of designing information…

  2. A Bayesian Model for Discovering Typological Implications

    CERN Document Server

    Daumé, Hal

    2009-01-01

    A standard form of analysis for linguistic typology is the universal implication. These implications state facts about the range of extant languages, such as ``if objects come after verbs, then adjectives come after nouns.'' Such implications are typically discovered by painstaking hand analysis over a small sample of languages. We propose a computational model for assisting at this process. Our model is able to discover both well-known implications as well as some novel implications that deserve further study. Moreover, through a careful application of hierarchical analysis, we are able to cope with the well-known sampling problem: languages are not independent.

  3. Cosmological implications of Heisenberg's principle

    CERN Document Server

    Gonzalo, Julio A

    2015-01-01

    The aim of this book is to analyze the all important implications of Heisenberg's Uncertainty Principle for a finite universe with very large mass-energy content such as ours. The earlier and main contributors to the formulation of Quantum Mechanics are briefly reviewed regarding the formulation of Heisenberg's Principle. After discussing “indeterminacy” versus ”uncertainty”, the universal constants of physics are reviewed and Planck's units are given. Next, a novel set of units, Heisenberg–Lemaitre units, are defined in terms of the large finite mass of the universe. With the help of Heisenberg's principle, the time evolution of the finite zero-point energy for the universe is investigated quantitatively. Next, taking advantage of the rigorous solutions of Einstein's cosmological equation for a flat, open and mixed universe of finite mass, the most recent and accurate data on the “age” (to) and the expansion rate (Ho) of the universe and their implications are reconsidered.

  4. Error Analysis and Its Implication

    Institute of Scientific and Technical Information of China (English)

    崔蕾

    2007-01-01

    Error analysis is the important theory and approach for exploring the mental process of language learner in SLA. Its major contribution is pointing out that intralingual errors are the main reason of the errors during language learning. Researchers' exploration and description of the errors will not only promote the bidirectional study of Error Analysis as both theory and approach, but also give the implication to second language learning.

  5. Female genital cutting: nursing implications.

    Science.gov (United States)

    Goldenstein, Rachel A

    2014-01-01

    Female genital cutting (FGC) is a practice that affects millions of girls and women worldwide. This deeply rooted practice has cultural, religious, and psychosexual meaning to its practitioners, but it also carries long-term physical and mental complications. Decried as a human rights violation, nonetheless this practice is still carried out today. Nurses are in a unique position to contact and educate women who have been cut or are at risk for mutilation. To advocate for these women, a thorough understanding of the practice of FGC, its cultural overtones, religious implications, and psychosexual effects is needed. PMID:23835896

  6. Pharmacogenomics and migraine: possible implications

    DEFF Research Database (Denmark)

    Tfelt-Hansen, P.; Brosen, K.

    2008-01-01

    Pharmacogenomics is the science about how inherited factors influence the effects of drugs. Drug response is always a result of mutually interacting genes with important modifications from environmental and constitutional factors. Based on the genetic variability of pharmacokinetic and in some...... cases pharmacodynamic variability we mention possible implications for the acute and preventive treatment of migraine. Pharmacogenomics will most likely in the future be one part of our therapeutic armamentarium and will provide a stronger scientific basis for optimizing drug therapy on the basis...

  7. Networking activism: implications for Greece

    Directory of Open Access Journals (Sweden)

    Pantelis Vatikiotis

    2011-12-01

    Full Text Available The outbreak of December 2008 against police brutality through a wave of demonstrations and street protests in Athens, which was strongly advocated by protest activities and practices across the world, addresses several issues in relation to the transformative potentials of mediated collective action. The paper critically evaluates different accounts of December events, probing then into thevery networking of that movement. From this perspective, it points out another aspect of the local-global interplay in protest culture along new mediating practices (beyond the creation of transnational publics, that of the implications of transnational networking for local social activism and identification, addressing relevant questions in the Greek context.

  8. Practical implications of 'postmodern philosophy'

    Directory of Open Access Journals (Sweden)

    Savić Mile V.

    2002-01-01

    Full Text Available The article examines the implications of the discourse about postmodernity. Postmodernity is analyzed as a complex discursive figure. Within the discourse about postmodernity three levels are distinguished: the postmodern condition, postmodernism, and reflection of the postmodern condition. Special attention is paid to globalization and the problem of the enforcement of modern projects in East-European societies, particularly Serbia. These societies are termed object-societies, while their modification of modernity is called eastmodernity. The author's answer to the complexity of the postmodern condition is a conception of the politics of subsistence.

  9. Philosophical Implications of Inflationary Cosmology

    CERN Document Server

    Knobe, J; Vilenkin, A; Knobe, Joshua; Olum, Ken D.; Vilenkin, Alexander

    2003-01-01

    Recent developments in cosmology indicate that every history having a nonzero probability is realized in infinitely many distinct regions of spacetime. Thus, it appears that the universe contains infinitely many civilizations exactly like our own, as well as infinitely many civilizations that differ from our own in any way permitted by physical laws. We explore the implications of this conclusion for ethical theory and for the doomsday argument. In the infinite universe, we find that the doomsday argument applies only to effects which change the average lifetime of all civilizations, and not those which affect our civilization alone.

  10. 高效液相色谱法同时测定土壤中毒死蜱残留及其有毒代谢物3,5,6-TCP%Determination of chlorpyrifos residue and its toxic metabolite product 3,5,6-TCP in soil by HPLC

    Institute of Scientific and Technical Information of China (English)

    孙宝利; 曾希柏

    2011-01-01

    A method for simultaneous determination of chlorpyrifos residue and its toxic metabolite product 3,5,6-TCP in soil by HPLC was established through selecting and optimizing conditions of separating? Extraction and cleaning-up. The recoveries and the limits of detection of the method were 59% ~87% and 0.0005~0.03μ/g,respectively. The RSD of recoveries of the method was no more than 5% which showed the method was stable and accurate,and it could satisy the requirement of pesticide residue determination in soil.%通过对色谱分离条件优化、提取体系建立和固相色谱小柱筛选,建立了用弗罗里硅土固相萃取小柱净化高效液相色谱法同时测定土壤中毒死蜱农药残留及其有毒代谢物3,5,6-TCP.方法加标回收率在59%~87%之间,检测限为0.0005~0.03 μg/g,日内回收率标准偏差RSD≤4.3%,日间回收率标准偏差RSD≤4.9%,方法能够满足土壤中毒死蜱残留以及有毒代谢物3,5,6-ICP的检测要求.

  11. Ophthalmic implications of seasonal affective disorder

    International Nuclear Information System (INIS)

    A review of seasonal affective disorder (SAD) is presented with a discussion of its standard treatment of phototherapy. A number of ophthalmic implications related to SAD are proposed. These implications relate to both the condition and the phototherapy used in its treatment, especially the use of full spectrum light which contains ultraviolet and near ultraviolet radiation. 12 references

  12. MARKETING IMPLICATION IN WINE ECONOMY

    Directory of Open Access Journals (Sweden)

    Ştefan MATEI

    2014-11-01

    Full Text Available The wine, a very complex product in viticulture, has proved its tremendous importance not only to the individual but rational nutrition and increasing national income of a country cultivators (evidenced by the upward trend of the share of crop production horticulture and viticulture in the global economy agricultural. More interesting is, given the continued growth in the number of scientific publications and their quality (at least since the 1980s - where "wine" is the centerpiece of these studies - we can not but be witnessing a growing interest more to this "potion" and found that the growing popularity of wine in the science reveals the emergence of a new academic field, ie "wine economy" (or wine-economy. This study aims to make a foray into "wine economy" and to outline some of the implications of marketing in this area.

  13. On the Product and Factorization of Lattice Implication Algebras

    Institute of Scientific and Technical Information of China (English)

    秦克云; 宋振明; 等

    1993-01-01

    In this paper,the concepts of product and factorization of lattice implication algebra are proposed,the relation between lattice implication product algebra and its factors and some properties of lattice implication product algebras are discussed.

  14. Mining TCGA data using Boolean implications.

    Science.gov (United States)

    Sinha, Subarna; Tsang, Emily K; Zeng, Haoyang; Meister, Michela; Dill, David L

    2014-01-01

    Boolean implications (if-then rules) provide a conceptually simple, uniform and highly scalable way to find associations between pairs of random variables. In this paper, we propose to use Boolean implications to find relationships between variables of different data types (mutation, copy number alteration, DNA methylation and gene expression) from the glioblastoma (GBM) and ovarian serous cystadenoma (OV) data sets from The Cancer Genome Atlas (TCGA). We find hundreds of thousands of Boolean implications from these data sets. A direct comparison of the relationships found by Boolean implications and those found by commonly used methods for mining associations show that existing methods would miss relationships found by Boolean implications. Furthermore, many relationships exposed by Boolean implications reflect important aspects of cancer biology. Examples of our findings include cis relationships between copy number alteration, DNA methylation and expression of genes, a new hierarchy of mutations and recurrent copy number alterations, loss-of-heterozygosity of well-known tumor suppressors, and the hypermethylation phenotype associated with IDH1 mutations in GBM. The Boolean implication results used in the paper can be accessed at http://crookneck.stanford.edu/microarray/TCGANetworks/.

  15. Mining TCGA data using Boolean implications.

    Directory of Open Access Journals (Sweden)

    Subarna Sinha

    Full Text Available Boolean implications (if-then rules provide a conceptually simple, uniform and highly scalable way to find associations between pairs of random variables. In this paper, we propose to use Boolean implications to find relationships between variables of different data types (mutation, copy number alteration, DNA methylation and gene expression from the glioblastoma (GBM and ovarian serous cystadenoma (OV data sets from The Cancer Genome Atlas (TCGA. We find hundreds of thousands of Boolean implications from these data sets. A direct comparison of the relationships found by Boolean implications and those found by commonly used methods for mining associations show that existing methods would miss relationships found by Boolean implications. Furthermore, many relationships exposed by Boolean implications reflect important aspects of cancer biology. Examples of our findings include cis relationships between copy number alteration, DNA methylation and expression of genes, a new hierarchy of mutations and recurrent copy number alterations, loss-of-heterozygosity of well-known tumor suppressors, and the hypermethylation phenotype associated with IDH1 mutations in GBM. The Boolean implication results used in the paper can be accessed at http://crookneck.stanford.edu/microarray/TCGANetworks/.

  16. Climatic implications of ice microphysics

    Energy Technology Data Exchange (ETDEWEB)

    Liou, K.N. [Univ. of Utah, Salt Lake City, UT (United States)

    1995-09-01

    Based on aircraft measurements of mid-latitude cirrus clouds, ice crystal size distribution and ice water content (IWC) are shown to be dependent on temperature. This dependence is also evident from the theoretical consideration of ice crystal growth. Using simple models of the diffusion and accretion growth of ice particles, the computed mean ice crystal size and IWC compare reasonably well with the measured mean values. The temperature dependence of ice crystal size and IWC has important climatic implications in that the temperature field perturbed by external radiative forcings, such as greenhouse warming, can alter the composition of ice crystal clouds. Through radiative transfer, ice microphysics can in turn affect the temperature field. Higher IWC would increase cloud solar albedo and infrared emissivity, while for a given IWC, larger crystals would reduce cloud albedo and emissivity. The competing effects produced by greenhouse temperature perturbations via ice micro-physics and radiation interactions and feedbacks are assessed by a one-dimensional radiative-convective climate model that includes an advanced radiation parameterization program. 3 figs.

  17. Green buildings: Implications for acousticians

    Science.gov (United States)

    Noble, Michael R.

    2005-04-01

    This presentation will deal with the practical implications of green design protocols of the US Green Building Council on interior acoustics of buildings. Three areas of particular consequence to acousticians will be discussed. Ventilation Systems: reduced energy consumption goals dictate reliance on natural cooling and ventilation using ambient air when possible. The consequent large openings in the building envelope to bring fresh air into rooms, and similar sized openings to transfer the mixed air out, can severely compromise the noise isolation of the rooms concerned. Radiant Cooling: the heavy concrete floors of buildings can be used as a thermal flywheel to lessen the cooling load, which forces the concrete ceilings to be exposed to the occupied rooms for heat transfer, and strictly limits the application of acoustical absorption on the ceilings. This challenges the room acoustics design. Green Materials: the LEED protocols require the elimination of potentially harmful finishes, including fibrous materials which may impact air quality or contribute to health problems. Since the backbone of sound absorption is glass and mineral fibres, this further challenges provision of superior room acoustics. Examples and commentary will be provided based on current and recent projects.

  18. Predictive implications of Gompertz's law

    Science.gov (United States)

    Richmond, Peter; Roehner, Bertrand M.

    2016-04-01

    Gompertz's law tells us that for humans above the age of 35 the death rate increases exponentially with a doubling time of about 10 years. Here, we show that the same law continues to hold up to age 106. At that age the death rate is about 50%. Beyond 106 there is so far no convincing statistical evidence available because the number of survivors are too small even in large nations. However, assuming that Gompertz's law continues to hold beyond 106, we conclude that the mortality rate becomes equal to 1 at age 120 (meaning that there are 1000 deaths in a population of one thousand). In other words, the upper bound of human life is near 120. The existence of this fixed-point has interesting implications. It allows us to predict the form of the relationship between death rates at age 35 and the doubling time of Gompertz's law. In order to test this prediction, we first carry out a transversal analysis for a sample of countries comprising both industrialized and developing nations. As further confirmation, we also develop a longitudinal analysis using historical data over a time period of almost two centuries. Another prediction arising from this fixed-point model, is that, above a given population threshold, the lifespan of the oldest persons is independent of the size of their national community. This prediction is also supported by empirical evidence.

  19. Predictive implications of Gompertz's law

    CERN Document Server

    Richmond, Peter

    2015-01-01

    Gompertz's law tells us that for humans above the age of 35 the death rate increases exponentially with a doubling time of about 10 years. Here, we show that the same law continues to hold even for ages over 100. Beyond 106 there is so far no statistical evidence available because the number of survivors is too small even in the largest nations. However assuming that Gompertz's law continues to hold beyond 106, we conclude that the mortality rate becomes equal to 1 at age 120 (meaning that there are 1,000 deaths in a population of one thousand). In other words, the upper bound of human life is near 120. The existence of this fixed-point has interesting implications. It allows us to predict the form of the relationship between death rates at age 35 and the doubling time of Gompertz's law. In order to test this prediction, we first carry out a transversal analysis for a sample of countries comprising both industrialized and developing nations. As further confirmation, we also develop a longitudinal analysis usi...

  20. Implications of zero economic growth

    Energy Technology Data Exchange (ETDEWEB)

    Thurow, L.C.

    1977-01-01

    The consequences of a zero economic growth (ZEG) policy are examined to see what limits to growth, some of which already exist, are desirable and what changes in our institutions are required to impose a no-growth policy. Past periods of zero or negative growth have increased unemployment, raised employability standards, and increased income-distribution inequalities with a subsequent lowering of the living standard. Zero population growth would offset this somewhat by freeing the capital now spent on education and career training and using it to raise per capita living standards if a work-sharing and unemployment-payment system were devised. Undesirable social implications would be felt both if a lack of employment opportunities reduced competition and consumption habits or if it led to intensive competition. Advocates of ZEG propose to restrain only those areas using nonrenewable resources and causing pollution of the environment, while expanding the service areas. The service sector (e.g., transportation and utilities) is also polluting and uses nonrenewable resources, however, pointing up their failure to account for indirect consumption. Many undeveloped countries already have ZEG but would not be content for the U.S. to halt growth opportunities. ZEG would be difficult to enforce and would do nothing to promote pollution control. (DCK)

  1. Knowledge Sharing and Implications to Employee Engagement

    OpenAIRE

    Abrar

    2011-01-01

    The objectives to be achieved in this research was to determine the application of knowledge sharing on the lecturers in Economics Faculty UNPAD, and knowing whether the lecturers are engaged or not, and determining the implications of knowledge sharing in employee engagement. This is an empirical study using description and verification methods with two variables. The implications of knowledge sharing to employee engagement includes the conditions of application of knowledge sharing, and the...

  2. Vague Congruences and Quotient Lattice Implication Algebras

    Directory of Open Access Journals (Sweden)

    Xiaoyan Qin

    2014-01-01

    Full Text Available The aim of this paper is to further develop the congruence theory on lattice implication algebras. Firstly, we introduce the notions of vague similarity relations based on vague relations and vague congruence relations. Secondly, the equivalent characterizations of vague congruence relations are investigated. Thirdly, the relation between the set of vague filters and the set of vague congruences is studied. Finally, we construct a new lattice implication algebra induced by a vague congruence, and the homomorphism theorem is given.

  3. Economic and policy implications of pandemic influenza.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Braeton J.; Starks, Shirley J.; Loose, Verne W.; Brown, Theresa Jean; Warren, Drake E.; Vargas, Vanessa N.

    2010-03-01

    Pandemic influenza has become a serious global health concern; in response, governments around the world have allocated increasing funds to containment of public health threats from this disease. Pandemic influenza is also recognized to have serious economic implications, causing illness and absence that reduces worker productivity and economic output and, through mortality, robs nations of their most valuable assets - human resources. This paper reports two studies that investigate both the short- and long-term economic implications of a pandemic flu outbreak. Policy makers can use the growing number of economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. Experts recognize that pandemic influenza has serious global economic implications. The illness causes absenteeism, reduced worker productivity, and therefore reduced economic output. This, combined with the associated mortality rate, robs nations of valuable human resources. Policy makers can use economic impact estimates to decide how much to spend to combat the pandemic influenza outbreaks. In this paper economists examine two studies which investigate both the short- and long-term economic implications of a pandemic influenza outbreak. Resulting policy implications are also discussed. The research uses the Regional Economic Modeling, Inc. (REMI) Policy Insight + Model. This model provides a dynamic, regional, North America Industrial Classification System (NAICS) industry-structured framework for forecasting. It is supported by a population dynamics model that is well-adapted to investigating macro-economic implications of pandemic influenza, including possible demand side effects. The studies reported in this paper exercise all of these capabilities.

  4. Results of Associated Implication Algebra on a Partial Ordered Set

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Some sufficient and necessary conditions that implication algebra on a partial ordered set is associated implication algebra are obtained, and the relation between lattice H implication algebra and associated implication algebra is discussed. Also, the concept of filter is proposed with some basic properties being studied.

  5. 77 FR 36394 - Safety Zone for Fireworks Display, Potomac River, National Harbor Access Channel; Oxon Hill, MD

    Science.gov (United States)

    2012-06-19

    ... Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History... the States, on the relationship between the national government and the States, or on the distribution... distribution of power and responsibilities between the Federal Government and Indian tribes. 12. Energy...

  6. Rough Implication%粗糙蕴涵

    Institute of Scientific and Technical Information of China (English)

    薛占熬; 何华灿

    2003-01-01

    Rough implication operator is the emphasis and difficulty in the study of rough logic. Due to the shortage of rough implication in [3]~[5], we redefine rough set and rough implication operator by Stone algebra, and introduce new rough operators such as rough intersection, rough union, and rough complement. Moreover the characteristics of the proposed rough implication are investigated ,and we also point out that the proposed implication operation is superior to that of three-valued Lukasiewicz logic.

  7. Variscan Oroclines: Implications for Pangea

    Science.gov (United States)

    Johnston, S. T.

    2012-12-01

    The supercontinent Pangea is commonly interpreted to have formed in the Upper Carboniferous as a result of collision of Gondwana and Laurussia. The western European Variscan Orogen is interpreted as the product of the Gondwana - Laurussia continental collision. In Iberia, the Variscan Orogen describes two coupled Early Permian oroclines; a northern, convex to the west Cantabrian orocline, and a southern, convex to the east Central Iberian orocline. Palinspastic restoration of the oroclines using paleomagnetic, structural and stratigraphic constraints yield a 2300 km long, linear orogen that: (1) consists of a west-facing lower Paleozoic passive margin sequence of Gondwanan affinity; (2) is characterized by an east-verging thrust belt that passes east into Carboniferous foreland basin sequences and west into a metamorphic hinterland; (3) is bound to the west by ophiolite and juvenile oceanic arc sequences obducted over the the distal west edge of the passive margin along east-verging thrust faults; (4) has syn- to post-kinematic granitic intrusions that young from 330 in the west to 290 in the east; and (5) is, in the east, characterized by sedimentary and volcanic sequences of Avalonian (Meguma) affinity which are separated from the passive margin sequence by a marginal basin ophiolite. This tectonic template can be used to interpret the Variscan orogen across all of western Europe, and shows that the orogen consists of a >7000 km long ribbon that extends from Cornwall, SW England, east along a north-verging northern limb, around the Bohemian orocline in the east into a south-verging southern limb that runs along the Mediterranean into the Iberian oroclines. The implication of this geometry is that: (1) Variscan orogenesis consisted of the Carboniferous collision of a juvenile oceanic arc with a Gondwanan-affinity ribbon continent and the related collapse of a marginal basin that separated the passive margin from Avalonian lithosphere; followed by (2) buckling of

  8. Effect of Irrigation Levels on Dissolved Organic Carbon Soil Distribution and the Depth Mobility of Chlorpyrifos Efecto de Niveles de Riego sobre la Distribución de Carbono Orgánico Disuelto en el Suelo y La Mobility en Profundidad de Clorpirifos

    Directory of Open Access Journals (Sweden)

    Julio Junod

    2009-09-01

    Full Text Available Water flows provided by irrigation systems may be associated with dissolved organic carbon (DOC content in the soil solution and may modify the mobility of pesticides, such as chlorpyrifos (CHP. These compounds were analyzed under field conditions, evaluating their distribution in the soil profile under excessive irrigation in a Humic Haploxerand soil. The trial was carried out in soil columns located under the canopy of apple trees (Malus domestica Borkh. in an orchard located in the Bío-Bío Region, Chile. The insecticide CHP was applied 120 g hL-1, and later the natural run off was collected from the foliage to the columns. Surface irrigation was used as a control, the equivalent to 4 L h-1 weekly, plus two treatments over the columns of 6 and 8 L h-1 per pulse, respectively. Samples were obtained at three column depths: 0-5, 5-20 and 20-30 cm. The results showed that in spite of the fact there was no interaction between depth and irrigation, a greater concentration of CHP was observed in the samples with greater water flow, with significant differences between the treatments at a depth of 20-30 cm, which suggests some level of influence on vertical mobility. DOC shows stratification with greater concentrations at the surface and lower concentrations at depth, with significant differences between the superficial stratum (0-5 cm and the lower strata (5-20, 20-30 cm. These results are discussed in relation to explaining the movement of CHP in the soil profile.Los flujos de agua aportados por los sistemas de riego pueden estar asociados al contenido de carbono orgánico disuelto (DOC en la solución del suelo y modificar la movilidad de pesticidas como el clorpirifos (CHP. Se analizan estos compuestos bajo condiciones de campo, evaluando su distribución en el perfil de suelo ante un exceso de riego en un suelo Humic Haploxerands. El ensayo se desarrolló en columnas de suelo ubicadas bajo la canopia de un huerto de manzanos (Malus domestica

  9. 40 CFR 180.342 - Chlorpyrifos; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... Peach 0.05 Peanut 0.2 Peanut, refined oil 0.2 Pear 0.05 Pecan 0.2 Pepper 1.0 Peppermint, tops 0.8 Peppermint, oil 8.0 Plum, prune, fresh 0.05 Poultry, fat 0.1 Poultry, meat 0.1 Poultry, meat byproducts...

  10. Impacts of Hypersaline Acclimation on Chlorpyrifos Toxicity to Salmonids

    OpenAIRE

    Maryoung, Lindley Anne

    2014-01-01

    As part of their unique life cycle, most Pacific salmonids transition from freshwater to saltwater, requiring various adjustments in physiology. However, molecular mechanisms underlying this transition are largely unknown. Additionally, acclimation to hypersaline conditions enhances the acute toxicity of certain thioether organophosphate and carbamate pesticides in some species of euryhaline fish, yet sublethal impacts have been far less studied. The current study aimed to determine underlyin...

  11. Clinical Implications of Incomplete Pancreas Divisum

    OpenAIRE

    Terumi Kamisawa; Yuyang Tu; Naoto Egawa; Kouji Tsuruta; Aatsutake Okamoto

    2006-01-01

    Context Incomplete pancreas divisum is a pancreatic anomaly that results in an inadequate communication between the ventral and dorsal pancreatic ducts. Although the relationship between complete pancreas divisum and pancreatitis has been contentious, clinical implications of incomplete pancreas divisum have not been noted. Objective This study was done to investigate the clinical significance of incomplete pancreas divisum. Patients and...

  12. Insulin-Dependent Diabetes Mellitus: Educational Implications.

    Science.gov (United States)

    Yousef, Jamal M. S.

    1995-01-01

    This article provides an overview of the educational implications of diabetes in children through discussion of the nature of diabetes, factors associated with educational performance, and the teacher's role in meeting the child's needs. It argues that teachers should treat these students as normal learners, without ignoring their unique needs or…

  13. The nuclear and its psychological implications

    International Nuclear Information System (INIS)

    From the 13. to 15. january 1977, the S.F.R.P. has organised at Paris, with the patronage of The National Institute of Health and Medical Research, the French Society of Radiology, a colloquium devoted to the nuclear and its psycho-implications sociological. It is a second edition, realised at the demand of the Antoine Beclere Center. (N.C.)

  14. Implication of SLA to ELT in China

    Institute of Scientific and Technical Information of China (English)

    赵芸霞

    2016-01-01

    Second language acquisition, or SLA, is the processes by which people learn languages in addition to their native tongue(s). Although the theories can not be directly used to solve the practical problems, they do have great significance to language teaching. This paper mainly discusses the implication of Krashen' SLA theory and offers some reference opinions to English teaching in China.

  15. Genetic Counseling: Ethical and Professional Role Implications.

    Science.gov (United States)

    Witmer, J. Melvin; And Others

    1986-01-01

    Genetic counseling assists people in identifying potential or manifest genetic problems, understanding their implications, making decisions about what course to follow, and working through psychological and social aspects as they affect individuals or couples. Four ethical principles and related ethical issues pertaining to autonomy, beneficence…

  16. Brexit: what are the implications for nurses?

    Science.gov (United States)

    2016-06-29

    The referendum result is in and appears to have caught the nation by surprise. Whatever the fallout from voters' decision to leave the EU, the implications for nursing are likely to be widespread and profound - and could take years to resolve. PMID:27353892

  17. Ritalin Update: Implications for Reading Teachers.

    Science.gov (United States)

    Cotter, Robert B., Jr.; Werner, Patrice Holden

    1987-01-01

    Investigates how Ritalin, a powerful stimulant drug frequently prescribed for children exhibiting hyperactive behavior, poor attention span, and/or distractibility, is prescribed for children in educational settings, what doses seem appropriate, and what effect Ritalin has on reading achievement. Discusses the implications of Ritalin research for…

  18. Cult Affiliation and Disaffiliation: Implications for Counseling.

    Science.gov (United States)

    Robinson, Beth; Frye, Ellen M.; Bradley, Loretta J.

    1997-01-01

    Data on cult membership and the characteristics of cults are provided. The process of cult affiliation and its relationship to family dynamics are reviewed. Defection, the processes of disaffiliation (voluntary and involuntary), and clinical symptoms after cult disaffiliation are discussed. Implications and recommendations for counselors are…

  19. Supervision and Motivational Theory: Some Implications.

    Science.gov (United States)

    Reyes, Donald J.

    1982-01-01

    Suggests useful implications for supervisors offered by motivational theories, including the importance of serving as a source of reinforcement for teachers and the necessity of helping the teacher make appropriate instructional choices and gather evidence on the effectiveness of those choices. (Author/JM)

  20. Some Implications of Human-Structure Interaction

    DEFF Research Database (Denmark)

    Pedersen, Lars

    2013-01-01

    On structures, humans may be active which may cause structural vibrations as human activity can excite structural vibration modes. However, humans may also be passive (sitting or standing on the structure). The paper addresses this subject and explores the implications of having passive humans...

  1. Brexit: what are the implications for nurses?

    Science.gov (United States)

    2016-06-29

    The referendum result is in and appears to have caught the nation by surprise. Whatever the fallout from voters' decision to leave the EU, the implications for nursing are likely to be widespread and profound - and could take years to resolve.

  2. Teacher's Experiences in PBL: Implications for Practice

    Science.gov (United States)

    Alves, Anabela C.; Sousa, Rui M.; Fernandes, Sandra; Cardoso, Elisabete; Carvalho, Maria Alice; Figueiredo, Jorge; Pereira, Rui M. S.

    2016-01-01

    Project-Based Learning (PBL) has been implemented in the first year of the Industrial Engineering and Management programme at the University of Minho, Portugal, since 2004/2005. The purpose of this paper is to analyse and discuss teachers' experiences in PBL in this programme and to explore its implications for student learning and for teaching…

  3. Linguistic Truth Values Lattice Implication Algebras

    Institute of Scientific and Technical Information of China (English)

    PAN Xiao-dong; XU Yang

    2006-01-01

    In order to study uncertainty reasoning and automatic reasoning with linguistic terms, in this paper, the set of basic linguistic truth values and the set of modifiers are defined, according to common sense; partially orderings are defined on them. Based on it, a lattice implication algebra model L18 of linguistic terms is built; furthermore, its some basic properties are discussed.

  4. Corporal Punishment: Legalities, Realities, and Implications.

    Science.gov (United States)

    Hinchey, Patricia H.

    2003-01-01

    Presents a quiz that will help readers determine the reliability of their own perceptions relating to corporal punishment in schools. Discusses U.S. Courts and corporal punishment, worldwide and nationwide legality, and the realities of corporal punishment in the United States. Discusses implications for what teachers can do to address corporal…

  5. Biological Implications of Gene-Environment Interaction

    Science.gov (United States)

    Rutter, Michael

    2008-01-01

    Gene-environment interaction (G x E) has been treated as both a statistical phenomenon and a biological reality. It is argued that, although there are important statistical issues that need to be considered, the focus has to be on the biological implications of G x E. Four reports of G x E deriving from the Dunedin longitudinal study are used as…

  6. Changing business environment: implications for farming

    OpenAIRE

    Malcolm, Bill

    2011-01-01

    The natural, technological, economic, political and social environment in which farmers farm constantly changes. History has lessons about change in agriculture and about farmers coping with change, though the future is unknowable and thus always surprising. The implication for farm operation is to prepare, do not predict.

  7. Commentary: Pedagogical Implications of Experimental SNS Research

    Science.gov (United States)

    Carreira, Maria; Potowski, Kim

    2011-01-01

    This special issue of the "Heritage Language Journal", guest edited by Silvina Montrul, unites four papers on different aspects of heritage Spanish speakers' linguistic abilities. In this commentary, we reexamine these important contributions with an eye toward implications for instruction and toward general trends for the field. In particular, we…

  8. Educational Implications of Microelectronics and Microprocessors.

    Science.gov (United States)

    Harris, N. D. C., Ed.

    This conference report explores microelectronic technology, its effect on educational methods and objectives, and its implications for educator responsibilities. Two main areas were considered: the significance of the likely impact of the large scale introduction of microprocessors and microelectronics on commercial and industrial processes, the…

  9. Ambiguity and Volatility : Asset Pricing Implications

    NARCIS (Netherlands)

    Pataracchia, B.

    2011-01-01

    Using a simple dynamic consumption-based asset pricing model, this paper explores the implications of a representative investor with smooth ambiguity averse preferences [Klibano¤, Marinacci and Mukerji, Econometrica (2005)] and provides a comparative analysis of risk aversion and ambiguity aversion.

  10. Physical implications of dynamical symmetry breaking

    International Nuclear Information System (INIS)

    Some model-independent physical implications of a class of hypercolorbased theories of dynamical symmetry-breaking are described and discussed. The role which e+e- colliders can play, in distinguishing between such theories and the canonical methodology, is underlined

  11. Theoretical, regulatory and practical implications of logistics

    Directory of Open Access Journals (Sweden)

    Mirosław Chaberek

    2014-03-01

    Full Text Available Background: The logistics has its practical input in creating economical strategies as well as in creating modern economic environment. Processes of planning, designing and functioning of logistic systems must be based both on the theoretical knowledge covering various areas as well as practical experiences to provide the required support.  To provide logistic services in the rational way, it is necessary to learn the complicated set of implications resulting from three areas covering the theoretical knowledge, practical ones as well as the regulation by the law. Methods: The triad of three concepts: theory, practice and regulation is the main area of consideration in relation to tasks of the logistic support provided by any organization for any production process. The aim of this paper focuses on the necessity of taking into account implications among theory, practice and regulation during the process of analyzing, designing and implementation of systems of the logistic support. The lack of awareness of differences between various implications or ignoring them must lead to irrational behaviors. Results: The implications among theory, practice and legislative regulation of logistics presented differently than usually, broaden the logistic knowledge and at the same time provide the tool of the rationalization of logistic services in all kinds of activities. Conclusions: The correct identification of tasks and functions of the logistics leads to the recognition of its subject and tasks and correct identification of implications occurring among theory, practice and regulation. This knowledge is indispensable in the process of creation of projects of logistic services of each activity, both business and non-business one.

  12. Rejoinder--Implications of "Online Display Advertising: Targeting and Obtrusiveness"

    OpenAIRE

    Avi Goldfarb; Catherine Tucker

    2011-01-01

    The commentaries on our work suggest several broader implications of our findings as well as a concern that we understate the size of the effect. In this rejoinder, we discuss our views on the regulatory implications, the implications for firm strategies, and the implications for our understanding of the underlying behavioral processes. We also acknowledge that our original calculation of $464 million in cost savings for industry is conservative. We conclude with a call for "privacy engineeri...

  13. Sleep disorders in Pregnancy: Glycaemic implications.

    Science.gov (United States)

    Kumar, K V S Hari

    2016-09-01

    Sleep is one of the essential biorhythms of the body that helps in optimum restoration of many body functions. The sleep-wake cycle is determined by the circadian centre and is responsible for the anabolic functions in the body. Infants require about 14 to 18 hours of sleep per day, which reduces gradually to about 8 hours in adults. Urbanization and evolutionary changes have altered the sleep hygiene and shortened the sleep duration. This lead to various sleep disorders like sleep disordered breathing, insomnia and narcolepsy. Sleep disorders lead to adverse cardio-metabolic consequences, including insulin resistance and hyperglycaemia. Pregnancy poses an enormous burden on the homeostasis of the women with alteration in many physiological functions. The sleep disorders during pregnancy lead to adverse foeto-maternal outcomes with long term cardiovascular implications. In this article, I review the pathophysiology of sleep disorders during pregnancy and their glycaemic implications. PMID:27582156

  14. Mirror neurons: their implications for group psychotherapy.

    Science.gov (United States)

    Schermer, Victor L

    2010-10-01

    Recently discovered mirror neurons in the motor cortex of the brain register the actions and intentions of both the organism and others in the environment. As such, they may play a significant role in social behavior and groups. This paper considers the potential implications of mirror neurons and related neural networks for group therapists, proposing that mirror neurons and mirror systems provide "hard-wired" support for the group therapist's belief in the centrality of relationships in the treatment process and exploring their value in accounting for group-as-a-whole phenomena. Mirror neurons further confirm the holistic, social nature of perception, action, and intention as distinct from a stimulus-response behaviorism. The implications of mirror neurons and mirroring processes for the group therapist role, interventions, and training are also discussed.

  15. Teacher's experiences in PBL: implications for practice

    Science.gov (United States)

    Alves, Anabela C.; Sousa, Rui M.; Fernandes, Sandra; Cardoso, Elisabete; Carvalho, Maria Alice; Figueiredo, Jorge; Pereira, Rui M. S.

    2016-03-01

    Project-Based Learning (PBL) has been implemented in the first year of the Industrial Engineering and Management programme at the University of Minho, Portugal, since 2004/2005. The purpose of this paper is to analyse and discuss teachers' experiences in PBL in this programme and to explore its implications for student learning and for teaching practices in higher education. For data collection, the research method used was written narratives to these teachers, at the end of the PBL semester. Findings suggest that teachers express a positive view of PBL as a learning approach. They identify student motivation and engagement, along with a better understanding of the application of concepts in real-life situations, as important outcomes of the project for students. Besides this, teachers also highlight the importance of the development of transversal skills by students throughout the project. Recommendations for future work and implications for practice will also be discussed.

  16. Learning and reconsolidation implicate different synaptic mechanisms.

    Science.gov (United States)

    Li, Yan; Meloni, Edward G; Carlezon, William A; Milad, Mohammed R; Pitman, Roger K; Nader, Karim; Bolshakov, Vadim Y

    2013-03-19

    Synaptic mechanisms underlying memory reconsolidation after retrieval are largely unknown. Here we report that synapses in projections to the lateral nucleus of the amygdala implicated in auditory fear conditioning, which are potentiated by learning, enter a labile state after memory reactivation, and must be restabilized through a postsynaptic mechanism implicating the mammalian target of rapamycin kinase-dependent signaling. Fear-conditioning-induced synaptic enhancements were primarily presynaptic in origin. Reconsolidation blockade with rapamycin, inhibiting mammalian target of rapamycin kinase activity, suppressed synaptic potentiation in slices from fear-conditioned rats. Surprisingly, this reduction of synaptic efficacy was mediated by post- but not presynaptic mechanisms. These findings suggest that different plasticity rules may apply to the processes underlying the acquisition of original fear memory and postreactivational stabilization of fear-conditioning-induced synaptic enhancements mediating fear memory reconsolidation. PMID:23487762

  17. Growth Laws in Cancer: Implications for Radiotherapy

    CERN Document Server

    Castorina, P; Gabriele, P; Guiot, C

    2006-01-01

    Comparing both, the more conventional Gompertz tumor growth law (GL) and the ``Universal'' law (UL), recently proposed and applied to cancer,we have investigated the growth law's implications on various radiotherapy regimen. According to GL, the surviving tumor cell fraction could be reduced 'ad libidum', independently of the initial tumor mass,simply by increasing the number of treatments. On the contrary, if tumor growth dynamics would indeed follow the Universal scaling law, there is a lower limit of the survival fraction that cannot be reduced any further regardless of the total number of treatments. This finding can explain the so called ``tumor size effect'' and re-emphasizes the importance of early diagnosis as it implies that radiotherapy may be successful provided the tumor mass at treatment onset is rather small. Taken together with our previous works, implications of these findings include revisiting standard radiotherapy regimen and overall treatment protocols.

  18. Implications of macro-areal linguistics

    Directory of Open Access Journals (Sweden)

    Corinna Leschber

    2015-09-01

    Full Text Available Implications of macro-areal linguisticsUsing the examples of some Balkan words with a difficult etymology, we attempt to show the possibilities for and implications of applying a macro-areal linguistic perspective to establish a wider view of the linguistic and cultural history of a region. Implikacje językoznawstwa makroarealnegoNa przykładzie niektórych bałkańskich słów o skomplikowanej etymologii autorka dokonuje próby pokazania możliwości i potencjału badawczego perspektywy makroarealnej. W każdym wypadku daje ona głębszy wgląd w historię, rozwój językowy i kulturowy tego regionu.

  19. Implications of LHC Searches for Massive Graviton

    CERN Document Server

    Tang, Yong

    2012-01-01

    With the latest LHC available results, we consider the generic constraints on massive graviton. Both dijet and dilepton resonance searches are used. The limits on parameter space can be applied to many models. As an illustration, we show the constraints for Randall-Sundrum (RS) model. Implications on massive graviton and the coupling strength are discussed. For $k/M_{pl}=0.1$, $M_G<2.2$ TeV region is excluded at 95% confidence level. We also present some interesting implications on the RS radion with respect to the 125 GeV excess at the LHC. For $k/M_{pl}=0.1$, $\\Lambda_\\phi<13.8$ TeV is excluded where $\\Lambda_\\phi$ is the scale to charactarize the interaction strengh of radion.

  20. Zebrafish Models for Human Acute Organophosphorus Poisoning.

    Science.gov (United States)

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

    2015-10-22

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

  1. Kinetics of pesticide degradation by human fresh frozen plasma (FFP) in vitro.

    Science.gov (United States)

    von der Wellen, Jens; Bierwisch, Anne; Worek, Franz; Thiermann, Horst; Wille, Timo

    2016-02-26

    There is an ongoing debate about the benefit of fresh frozen plasma (FFP) infusion in organophosphorus (OP) pesticide-poisoned patients. This prompted us to investigate the kinetics of OP pesticide degradation by FFP with an enzymatic assay in vitro. Degradation was rapid with shortest half-lives of 19.5s for chlorpyrifos-oxon, 6.3min for paraoxon-ethyl and 17.9min for dichlorvos. Heptenophos (78.0min), mevinphos (101.8min), profenofos (162.3min) and malaoxon (179.7min) showed half-lives of up to 3h. Substantial longer degradation half-lives of 69.7-80.8h were determined with chlorfenvinphos and bromfenvinphos. Methamidophos and omethoate showed no degradation by FFP indicated by half-lives similar to spontaneous hydrolysis. In conclusion, degradation by FFP depends on the particular OP pesticide and the used FFP batch.

  2. ECONOMIC IMPLICATIONS OF INSUFFICIENT HEALTH LITERACY

    OpenAIRE

    Dukić, Nikolina; Arbula Blecich, Andrea; Cerović, Ljerka

    2013-01-01

    The main goal of this paper is to elaborate the importance of health literacy in cost-effective utilization of health care services which influence the efficiency of the entire health care sector. In order to complement the theoretical framework of the economic implications and the circular influence of health literacy on the economy, an empirical analysis was carried out using S–TOFHLA. The results suggest that the patients’ personal characteristics and the accessibil...

  3. The remnant CP transformation and its implications

    CERN Document Server

    Gonzalez-Canales, Felix

    2016-01-01

    In the context of remnant CP transformations, I briefly discuss a generalized $\\mu-\\tau$ reflection symmetry, where the "Majorana" phases have CP conserving values, which are directly related with the CP parities of neutrino states. Also, one finds that the "Dirac-like" CP violation phase is correlated with the atmospheric mixing angle, giving important phenomenological implications for current and future long baseline oscillation neutrino experiments.

  4. Social Implications of Neo - Imperialism in India

    OpenAIRE

    Dhas, Albert Christopher; Helen, Mary Jacqueline

    2010-01-01

    The globalisation process, which aimed at integration of economies and global development, is basically a reflection of neo-imperialism ideas. The question addressed in this paper is: what are the social implications of the neo-imperialism (globalisation) process in India, particularly on the social security aspects of the working population? Accordingly, an attempt is made in this paper to examine changes in the social security status of the working population that have been brought ab...

  5. Thalamocortical synchronization and cognition: implications for schizophrenia?

    OpenAIRE

    Uhlhaas, Peter J.; Roux, Frederic; Singer, Wolf

    2013-01-01

    Cognitive deficits are a core dysfunction in schizophrenia. In this issue of Neuron, Parnaudeau et al. (2013) investigated synchronization in thalamocortical pathways in an animal model to address the disconnection between brain regions as a mechanism for working memory impairments in the disorder.implicated dysfunctional neural oscillations in the explanation of cognitive deficits and certain clinical symptoms of schizophrenia. Specifically, we will focus on findings that have examined neura...

  6. Molecular heterogeneity in glioblastoma: potential clinical implications

    Directory of Open Access Journals (Sweden)

    Nicole Renee Parker

    2015-03-01

    Full Text Available Glioblastomas, (grade 4 astrocytomas, are aggressive primary brain tumors characterized by histopathological heterogeneity. High resolution sequencing technologies have shown that these tumors also feature significant inter-tumoral molecular heterogeneity. Molecular subtyping of these tumors has revealed several predictive and prognostic biomarkers. However, intra-tumoral heterogeneity may undermine the use of single biopsy analysis for determining tumor genotype and has implications for potential targeted therapies. The clinical relevance and theories of tumoral molecular heterogeneity in glioblastoma are discussed.

  7. Aggregate Implications of Micro Asset Market Segmentation

    OpenAIRE

    Chris Edmond; Pierre-Olivier Weill

    2011-01-01

    This paper develops a consumption-based asset pricing model to explain and quantify the aggregate implications of a frictional financial system, comprised of many financial markets partially integrated with one another. Each of our micro financial market's is inhabited by traders who are specialized in that markets type of asset. We specify exogenously the level of segmentation that ultimately determines how much idiosyncratic risk traders bear in their micro market and derive aggregate asset...

  8. Bioavailability: implications for science/cleanup policy

    Energy Technology Data Exchange (ETDEWEB)

    Denit, Jeffery; Planicka, J. Gregory

    1998-12-01

    This paper examines the role of bioavailability in risk assessment and cleanup decisions. Bioavailability refers to how chemicals ''behave'' and their ''availability'' to interact with living organisms. Bioavailability has significant implications for exposure risks, cleanup goals, and site costs. Risk to human health and the environment is directly tied to the bioavailability of the chemicals of concern.

  9. Breast cancer heterogeneity: mechanisms, proofs, and implications

    OpenAIRE

    Yi-Hsuan Hsiao, Ming-Chih Chou, Carol Fowler, Jeffrey T. Mason, Yan-gao Man

    2010-01-01

    Human breast cancer represents a group of highly heterogeneous lesions consisting of about 20 morphologically distinct subtypes with substantially different molecular and/or biochemical signatures, clinical courses, and prognoses. This study analyzed the possible correlation between the morphological presentations of breast cancer and two hypothesized models of carcinogenesis, in order to identify the intrinsic mechanism(s) and clinical implications of breast cancer heterogeneity.

  10. Breast cancer heterogeneity: mechanisms, proofs, and implications

    Directory of Open Access Journals (Sweden)

    Yi-Hsuan Hsiao, Ming-Chih Chou, Carol Fowler, Jeffrey T. Mason, Yan-gao Man

    2010-01-01

    Full Text Available Human breast cancer represents a group of highly heterogeneous lesions consisting of about 20 morphologically distinct subtypes with substantially different molecular and/or biochemical signatures, clinical courses, and prognoses. This study analyzed the possible correlation between the morphological presentations of breast cancer and two hypothesized models of carcinogenesis, in order to identify the intrinsic mechanism(s and clinical implications of breast cancer heterogeneity.

  11. FEMALE URETHRA – ANATOMO-CLINICAL IMPLICATIONS

    OpenAIRE

    C. Zanoschi; R. Moldovanu

    2006-01-01

    Urethra represents the last segment of the urinary tract. We present a comprehensive account of the female urethral anatomy, including its component structures, neurovascular supply, relationship to adjacent structures (the vagina, bladder and vestibular glands, and connective tissue supports) and histology. These data are important because the distal segment of the female urethra is implicated in the mechanism of urinary continence (female stress urinary incontinence is thought to result f...

  12. Implications of Theoretical Ideas Regarding Cold Fusion

    OpenAIRE

    Abbas, Afsar

    1995-01-01

    A lot of theoretical ideas have been floated to explain the so called cold fusion phenomenon. I look at a large subset of these and study further physical implications of the concepts involved. I suggest that these can be tested by other independent physical means. Because of the significance of these the experimentalists are urged to look for these signatures. The results in turn will be important for a better understanding and hence control of the cold fusion phenomenon.

  13. 2014 and beyond: implications for displacement

    Directory of Open Access Journals (Sweden)

    Aidan O’Leary

    2014-05-01

    Full Text Available 2014 marks a watershed for Afghanistan, with the withdrawal of the International Security Assistance Force after twelve years, and the very real risks this withdrawal poses to the capacity of the Afghan state to meet the many internal and external challenges faced by the country. These challenges have significant implications for displaced and returning Afghans and for the potential for displacement in the future.

  14. Environment Implications of China's WTO Accession

    Institute of Scientific and Technical Information of China (English)

    Li Shantong; He Jianwu

    2006-01-01

    China's WTO accession will have important environmental implications. This article aims at providing environmental analysis of the impact of China's accession to the WTO, based on its final offer for WTO accession and a 53-sector, recursive dynamic computable general equilibrium (CGE) model of China. We try to provide some empirical evidences for policy makers to evaluate the effects of China's WTO accession from environmental prospective.

  15. On the normative implications of social neuroscience

    OpenAIRE

    Arleen Salles

    2013-01-01

    Within the last decades, brain science has been offering new insights into the relationship among diverse psychological processes and the neural correlates of our moral thought and behavior. Despite the distinction between the explanatory/descriptive nature of science and the normative nature of morality, some neuroethicists have claimed that neuroscientific findings have normative implications. In this paper, I identify three interpretations of the claim. The first focuses on neuroscience’s ...

  16. Investigating Variations in Gameplay: Cognitive Implications

    Directory of Open Access Journals (Sweden)

    Kamran Sedig

    2015-01-01

    Full Text Available There is increasing interest in creating computer games for learning, problem solving, and other high-level cognitive activities. When investigating whether gameplay is conducive to such activities, gameplay is often studied as a whole. As a result, cognitive implications can be linked to the game but not to its structural elements. Given that gameplay arises from interaction between the player and the game, it is the structural components of interaction that should be investigated to better understand the design of gameplay. Furthermore, minor variations in the components of interaction can have significant cognitive implications. However, such variation has not been studied yet. Thus, to gain a better understanding of how we can study the effect of interaction on the cognitive aspect of gameplay, we conducted an exploratory investigation of two computer games. These games were isomorphic at a deep level and only had one minor difference in the structure of their interaction. Volunteers played these games and discussed the cognitive processes that emerged. In one game, they primarily engaged in planning, but in the other game they primarily engaged in visualizing. This paper discusses the results of our investigation as well as its implications for the design of computer games.

  17. Pesticides in amphibian habitats of Central and Northern California, USA

    Science.gov (United States)

    Fellers, Gary M.; Sparling, W; McConnell, Laura; Kleeman, Patrick M.; Drakeford, Leticia

    2013-01-01

    Previous studies have indicated that toxicity from pesticide exposure may be contributing to amphibian declines in California and that atmospheric deposition could be a primary pathway for pesticides to enter amphibian habitats. We report on a survey of California wetlands sampled along transects associated with Lassen Volcanic National Park, Lake Tahoe, Yosemite National Park, and Sequoia National Park. Each transect ran from the Pacific coast to the Cascades or Sierra Nevada mountains. Pacific chorus frogs (Pseudacris regilla), water, and sediment were collected from wetlands in 2001 and 2002. Twenty-three pesticides were found in frog, water, or sediment samples. Six contaminants including trifluralin, α-endosulfan, chlordanes, and trans-nonachlor were found in adult P. regilla. Seventeen contaminants were found in sediments, including endosulfan sulfate, chlordanes, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene (4,4′-DDE), and chlorpyrifos. The mean number of chemicals detected per pond in sediments was 2.4 (2.5, standard deviation). In water, 17 chemicals were detected, with β-endosulfan being present in almost all samples. Trifluralin, chlordanes, and chlorpyrifos were the next most common. The mean number of chemicals in water per pond was 7.8 (2.9). With the possible exception of chlorpyrifos oxon in sediments and total endosulfans, none of the contaminants exceeded known lethal or sublethal concentrations in P. regilla tissue. Endosulfans, chlorpyrifos, and trifluralin were associated with historic and present day population status of amphibians. Cholinesterase, an essential neurological enzyme that can be depressed by certain pesticides, was reduced in tadpoles from areas with the greatest population declines.

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

    Science.gov (United States)

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

    2015-10-01

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

  19. GLOBAL WARMING: IMPLICATIONS AND ANTICIPATORY ADAPTIVE MEASURES

    Directory of Open Access Journals (Sweden)

    MUNESH KUMAR

    2011-12-01

    Full Text Available Our earth is warming up. There is no denying to this fact that the gradual heating up of our globe has a tremendous effect on the climate. It in turn has affected the biotic factors that make up our biosphere, eventually directing the course of our socio-economic development. Some workers are, however, optimistic about this natural phenomenon. Various ways have been suggested to mitigate the effects of global warming, but the damage already done cannot be revoked. Hence, the thing that we are left with is to go for anticipatory adaptive measures so as to tone down the intensity of future implications of global warming.

  20. Ionization potentials some variations, implications and applications

    CERN Document Server

    Ahrens, L H

    1983-01-01

    Ionization Potentials: Some Variations, Implications and Applications covers several aspects of ionization potential that is a highly significant parameter in controlling the properties of electric discharge. Comprised of 17 chapters, the book covers topic relevant to ionization potentials, such as properties, concepts, and applications, in order to understand and fully comprehend all aspects of ionization potential. The opening chapter is a review of ionization potentials and a discussion of trends and features. The succeeding chapters then tackle complex topics such as the s and p electrons;

  1. Professional socialization: implications for occupational therapy education.

    Science.gov (United States)

    Sabari, J S

    1985-02-01

    This article examines the implications that adult socialization theory can have on occupational therapy education. Sociological literature about professional socialization is reviewed and related to the preparation of occupational therapists. The discussion includes a description of the goals, processes, and participants in professional socialization. Consistency of socializing influences is presented as a critical factor in the formation of strong professional role identities. Finally, the article considers which values and attitudes may be transmitted during the socialization process for occupational therapists and other health professionals. PMID:3976829

  2. Adolescent Health Implications of New Age Technology.

    Science.gov (United States)

    Jacobson, Cara; Bailin, Alexandra; Milanaik, Ruth; Adesman, Andrew

    2016-02-01

    This article examines the health implications of new age technology use among adolescents. As Internet prevalence has increased, researchers have found evidence of potential negative health consequences on adolescents. Internet addiction has become a serious issue. Pornography is now easily accessible to youth and studies have related pornography with several negative health effects. Cyberbullying has become a large problem as new age technologies have created a new and easy outlet for adolescents to bully one another. These technologies are related to increased morbidity and mortality, such as suicides due to cyberbullying and motor vehicle deaths due to texting while driving. PMID:26613696

  3. Massive neutron stars and their implications

    Indian Academy of Sciences (India)

    T K Jha; Keshab C Panda

    2014-05-01

    Recent observations of high mass pulsar PSRJ1614-2230 has raised serious debate over the possible role of exotics in the dense core of neutron stars. The precise measurement of mass of the pulsar may play a very important role in limiting equation of state (EoS) of dense matter and its composition. Indirectly, it may also shape our understanding of the nucleon–hyperon or hyperon–hyperon interactions which is not well known. Within the framework of an effective chiral model, we compute models of neutron stars and analyse the hyperon composition in them. Further related implications are also discussed.

  4. Corporate Language and Implications for Organizational Learning

    DEFF Research Database (Denmark)

    Zølner, Mette

    2013-01-01

    is insufficient to leverage contextually specific and culturally embedded knowledge. This indicates the need for disentangling language and culture. The paper further argues for the need to go beyond national language to consider how prevailing kinds of corporate talk may curb headquarters potential for learning......This paper explores empirically implications of language use for MNCs’ learning from subsidiaries. Drawing on sociolinguistic literature, the article argues that while employing a single corporate language facilitates quick and direct communication of explicit knowledge, such a language design...... from cultural and contextual diversity....

  5. Implication-based fuzzy semiautomaton of a finite group and its properties

    Science.gov (United States)

    Selva Rathi, M.; Michael Anna Spinneli, J.

    2016-06-01

    Implication-based fuzzy semiautomaton (IBFSA) of a finite group is defined. The ideas of an implication-based fuzzy kernel and implication-based fuzzy subsemiautomaton of an IBFSA over a finite group are developed using the concept of implication-based fuzzy subgroup and implication-based fuzzy normal subgroup. The necessary and sufficient condition for the implication-based fuzzy kernel and implication-based fuzzy subsemiautomaton of an IBFSA and few other results are proved in this paper.

  6. A synopsis of collective alpha effects and implications for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Sigmar, D.J.

    1990-10-01

    This paper discusses the following: Alpha Interaction with Toroidal Alfven Eigenmodes; Alpha Interaction with Ballooning Modes; Alpha Interaction with Fishbone Oscillations; and Implications for ITER.

  7. Forensic implications: adolescent sexting and cyberbullying.

    Science.gov (United States)

    Korenis, Panagiota; Billick, Stephen Bates

    2014-03-01

    Adolescence is marked by establishing a sense of identity, core values, a sense of one's relationship to the outside world and heightened peer relationships. In addition, there is also risk taking, impulsivity, self exploration and dramatic increase in sexuality. The dramatic increase in the use of cell phones and the Internet has additional social implications of sexting and cyberbullying. Sexting refers to the practice of sending sexually explicit material including language or images to another person's cell phone. Cyberbullying refers to the use of this technology to socially exclude, threaten, insult or shame another person. Studies of cell phone use in the 21st century report well over 50% of adolescents use them and that text messaging is the communication mode of choice. Studies also show a significant percentage of adolescents send and receive sex messaging, both text and images. This paper will review this expanding literature. Various motivations for sexting will also be reviewed. This new technology presents many dangers for adolescents. The legal implications are extensive and psychiatrists may play an important role in evaluation of some of these adolescents in the legal context. This paper will also make suggestions on future remedies and preventative actions.

  8. Forensic implications: adolescent sexting and cyberbullying.

    Science.gov (United States)

    Korenis, Panagiota; Billick, Stephen Bates

    2014-03-01

    Adolescence is marked by establishing a sense of identity, core values, a sense of one's relationship to the outside world and heightened peer relationships. In addition, there is also risk taking, impulsivity, self exploration and dramatic increase in sexuality. The dramatic increase in the use of cell phones and the Internet has additional social implications of sexting and cyberbullying. Sexting refers to the practice of sending sexually explicit material including language or images to another person's cell phone. Cyberbullying refers to the use of this technology to socially exclude, threaten, insult or shame another person. Studies of cell phone use in the 21st century report well over 50% of adolescents use them and that text messaging is the communication mode of choice. Studies also show a significant percentage of adolescents send and receive sex messaging, both text and images. This paper will review this expanding literature. Various motivations for sexting will also be reviewed. This new technology presents many dangers for adolescents. The legal implications are extensive and psychiatrists may play an important role in evaluation of some of these adolescents in the legal context. This paper will also make suggestions on future remedies and preventative actions. PMID:24129662

  9. Global implications of China's healthcare reform.

    Science.gov (United States)

    Yan, Fei; Tang, Shenglan; Zhang, Jian

    2016-01-01

    The ongoing healthcare reform in China has a powerful spillover effect beyond the health sector and the borders of China. A successful completion of the Chinese reform will offer a new model for social justice development, shift the global economy toward sustainability and create a new hub for science and technology in medical and health science. However, reforming the healthcare system in the most populated country is a daunting task. China will not live up to its promise, and all the potentials may end with hype not hope if coherent national strategies are not constructed and state-of-the-art navigation is not achieved with staggering domestic and global challenges. The cost of failure will be immensely high, socioeconomic costs for Chinese and an opportunity cost for the world as a whole. A full appreciation of the global implications of China's healthcare reform is crucial in keeping China receptive toward good practices evidence-approved elsewhere and open minded to fulfill its international obligations. More critically, the appreciation yields constructive engagements from global community toward a joint development and global prosperity. The current report provides a multiple disciplinary assessment on the global implications of the healthcare reform in China. PMID:24890392

  10. Abiding IPRs in Technological Implications for Pakistan

    Directory of Open Access Journals (Sweden)

    Murtaza Hussain Shaikh A

    2014-03-01

    Full Text Available The focal objective of this article is to analyze the role of intellectual property rights in technological implications within a general context. The performance of the IPRs system and its interaction with national innovation system with some degrees of success has also been highlighted. Major encounter over subsequently decade will be to identify policies and solutions that would permit marketplace economy to flourish in the framework of this intellectual property insurrection. There has been a lot of dispute on the role of intellectual property protection regime specially in fostering innovation, technology development of a country. IPRs are expected to emboli the innovation, by rewarding inventor with a grant of domination rights over the mercantile exploitation for a specified time period. This article tries to attempts to review the role of the IPR regime in technological development and also have suggested some policy implications for country like Pakistan and some reflecting lessons for other developing countries with similar settings and common characteristics. Keywords -

  11. Inter-compartmental transport of organophosphate and pyrethroid pesticides in South China: implications for a regional risk assessment.

    Science.gov (United States)

    Li, Huizhen; Wei, Yanli; Lydy, Michael J; You, Jing

    2014-07-01

    The dynamic flux of an organophosphate and four pyrethroid pesticides was determined in an air-(soil)-water-sediment system based on monitoring data from Guangzhou, China. The total air-water flux, including air-water gaseous exchange and atmospheric deposition, showed deposition from air to water for chlorpyrifos, bifenthrin and cypermethrin, but volatilization for lambda-cyhalothrin and permethrin. The transport of the pesticides from overlying water to sediment suggested that sediment acted as a sink for the pesticides. Additionally, distinct annual atmospheric depositional fluxes between legacy and current-use pesticides suggested the role of consumer usage in their transport throughout the system. Finally, pesticide toxicity was estimated from annual air-water-sediment flux within an urban stream in Guangzhou. A dynamic flux-based risk assessment indicated that inter-compartmental transport of chlorpyrifos decreased its atmospheric exposure, but had little influence on its aquatic toxicity. Instead, water-to-sediment transport of pyrethroids increased their sediment toxicity, which was supported by previously reported toxicity data. PMID:24704807

  12. L-型模糊格蕴涵代数%L-fuzzy Lattice Implication Algebra

    Institute of Scientific and Technical Information of China (English)

    宋庆龙; 李春瑞; 赵光峰

    2006-01-01

    This paper introduced the concept of L-fuzzy sub lattice implication algebra and discussed its properties. Proved that the intersection set of a family of L-fuzzy sub lattice implication algebras is a L-fuzzy sub lattice implication algebra, that a L-fuzzy sub set of a lattice implication algebra is a L-fuzzy sub lattice implication algebra if and only if its every cut set is a sub lattice implication algebra, and that the image and original image of a L-fuzzy sub lattice implication algebra under a lattice implication homomorphism are both L-fuzzy sub lattice implication algebras.

  13. Subdirectly Irreducible and Directly Indecomposable Lattice Implication Algebras

    Institute of Scientific and Technical Information of China (English)

    WANG Xue-fang; XU Yang; SONG Zhen-ming

    2004-01-01

    Lattice implication algebra is analgebraic structure that is established by combining lattice andimplicative algebra. It originated from the study onlattice-valued logic. In this paper, we characterize two specialclasses of lattice implication algebra, namely, subdirectlyirreducible and directly indecomposable lattice implicationalgebras. Some important results are obtained.

  14. Education System Reform in China after 1978: Some Practical Implications

    Science.gov (United States)

    Sun, Miantao

    2010-01-01

    Purpose: This paper aims to provide an overview of education system reform in China since 1978, and its practical implications. Design/methodology/approach: Data were collected from literature review and interview. An overview of education system reform and its practical implications was found through data analysis. Findings: There has been two…

  15. Motivation and Gifted Students: Implications of Theory and Research

    Science.gov (United States)

    Clinkenbeard, Pamela R.

    2012-01-01

    An analysis of contemporary motivation theories reveals implications for gifted and talented students. The expectancy-value framework, intrinsic-extrinsic motivation theories, goal orientations, self-efficacy and other self-perceptions, and attribution theory are described and discussed with respect to implications for the psychology and education…

  16. Local sustainable development – implications for local public finances

    OpenAIRE

    FLORIN OPREA; ELENA CIGU

    2012-01-01

    Local sustainable development implications on local public finances are complex because this phenomenon explained by development strategies mobilizes local resources towards achieving the three dimensions that define the phenomenon. This paper aims to develop these implications in Romania, showing that the local development strategy determines the reorganization of local government finances in identifying resources to cover expenses, which are directed towards achieving the goals.

  17. Macroeconomic and policy implications of population aging in Brazil

    OpenAIRE

    Jorgensen, Ole Hagen

    2011-01-01

    This paper analyzes the macroeconomic implications of population aging in Brazil. Three alternative yet complementary methodologies are adopted, and depending on policy responses to the fiscal implications of aging, there are two main findings: First, saving rates could increase and not necessarily fall as a consequence of aging in Brazil -- thus contradicting conventional views. Second, l...

  18. Implications of global warming on human health

    International Nuclear Information System (INIS)

    Due to the build up of green house gases in atmosphere, less heat escapes through the atmosphere promoting global warming. This may result in world wide droughts, sea-level rise inundating islands and coastal countries, cataclysmic hurricanes etc. Human health as a result of these changes, will be affected both physiologically and psychologically. Physiological effects may be more pronounced in cases occurring due to changes in rainfall and temperature patterns, food production amounts, water availability, etc. Psychological impact may be more in cases of catastrophes like floods, hurricanes or famine. In this paper, an attempt has been made to highlight the implications of global warming on human health due to temperature change. Food production changes and ultra-violet radiation effects and cataclysmic disaster effects. (author)

  19. Phonological development in young bilinguals: clinical implications.

    Science.gov (United States)

    Core, Cynthia; Scarpelli, Chiara

    2015-05-01

    This article reviews recent research on bilingual phonological development and describes the nature of bilingual phonology, focusing on characteristics of cross-linguistic influence on bilingual phonological abilities. There is evidence of positive and negative transfer (acceleration and deceleration) on children's phonological abilities. Several methodological issues limit the ability to generalize findings from previous research to larger groups of bilingual children (e.g., small sample size, lack of consideration of age of acquisition of each language, and language abilities of the participants). Sources of heterogeneity in language development are presented and discussed. Phonological abilities are related to language abilities in bilingual first language learners of English and Spanish. Empirical evidence from research in our laboratory supports this claim. We discuss implications of research findings and limitations for future research and clinical practice. We provide specific recommendations for bilingual research and for clinical assessment of young bilingual children.

  20. Prescription drug abuse: problem, policies, and implications.

    Science.gov (United States)

    Phillips, Janice

    2013-01-01

    This article provides an overview on prescription drug abuse and highlights a number of related legislative bills introduced during the 112th Congress in response to this growing epidemic. Prescription drug abuse has emerged as the nation's fastest growing drug problem. Although prescription drugs have been used effectively and appropriately for decades, deaths from prescription pain medicine in particular have reached epidemic proportions. Bills related to prescription drug abuse introduced during the 112th Congress focus on strengthening provider and consumer education, tracking and monitoring prescription drug abuse, improving data collection on drug overdose fatalities, combating fraud and abuse in Medicare and Medicaid programs, reclassifying drugs to make them more difficult to prescribe and obtain, and enforcing stricter penalties for individuals who operate scam pain clinics and sell pain pills illegitimately. This article underscores the importance of a multifaceted approach to combating prescription drug abuse and concludes with implications for nursing. PMID:23245611

  1. Destination image: Origins, Developments and Implications

    Directory of Open Access Journals (Sweden)

    Sérgio Dominique Ferreira Lopes

    2011-01-01

    Full Text Available Over the last few decades, tourism has become one of the main sectors of the global economy, not only because of its contribution to the Gross Domestic Product (GDP of different countries, but also because of the employment it generates. Since 2009, however, the results of tourism have been severely affected by the economic and financial crisis and it is now essential to analyze the key elements of tourist consumer behavior. In this context, the image that a destination transmits to the market becomes one of the elements which influence tourists the most when choosing a tourist destination. The authors therefore aim to identify the main elements that characterize the image of a tourist destination, as well as their implications for the management of tourist destinations.

  2. Exploring Forensic Implications of the Fusion Drive

    Directory of Open Access Journals (Sweden)

    Shruti Gupta

    2014-09-01

    Full Text Available This paper explores the forensic implications of Apple's Fusion Drive. The Fusion Drive is an example of auto-tiered storage. It uses a combination of a flash drive and a magnetic drive. Data is moved between the drives automatically to maximize system performance. This is different from traditional caches because data is moved and not simply copied. The research included understanding the drive structure, populating the drive, and then accessing data in a controlled setting to observe data migration strategies. It was observed that all the data is first written to the flash drive with 4 GB of free space always maintained. If data on the magnetic drive is frequently accessed, it is promoted to the flash drive while demoting other information. Data is moved at a block-level and not a file-level. The Fusion Drive didn't alter the timestamps of files with data migration.

  3. Heat Shock Proteins and their clinical Implications

    Directory of Open Access Journals (Sweden)

    M. M. Pathan

    Full Text Available Knowledge of the physiological role of heat shock proteins is currently limited; however better understanding of their function and thereby the acquisition of the capacity to harness their power might lead to their use as therapeutic agents and revolutionize clinical practice in a number of areas. Future work is needed to translate the experimental data on the capacity of heat shock proteins to induce tumor protection and immunity to infectious agents into the clinical environment. Approach to cancer vaccine is based on the role of HSP in the presentation of antigens. In several infections and especially autoimmune diseases, the implications of immune responses against HSP are still not properly or fully understood. HSP have clinical significance in conditions such as cardiac hypertrophy, vascular wall injury, cardiac surgery, ischemic preconditioning and ageing. [Veterinary World 2010; 3(12.000: 558-560

  4. Clinical implications of hedgehog signaling pathway inhibitors

    Institute of Scientific and Technical Information of China (English)

    Hailan Liu; Dongsheng Gu; Jingwu Xie

    2011-01-01

    Hedgehog was first described in Drosophila melanogaster by the Nobel laureates Eric Wieschaus and Christiane Nusslein-Volhard. The hedgehog (Hh) pathway is a major regulator of cell differentiation,proliferation, tissue polarity, stem cell maintenance, and carcinogenesis. The first link of Hh signaling to cancer was established through studies of a rare familial disease, Gorlin syndrome, in 1996. Follow-up studies revealed activation of this pathway in basal cell carcinoma, medulloblastoma and, leukemia as well as in gastrointestinal, lung, ovarian, breast, and prostate cancer. Targeted inhibition of Hh signaling is now believed to be effective in the treatment and prevention of human cancer. The discovery and synthesis of specific inhibitors for this pathway are even more exciting. In this review, we summarize major advances in the understanding of Hh signaling pathway activation in human cancer, mouse models for studying Hhmediated carcinogenesis, the roles of Hh signaling in tumor development and metastasis, antagonists for Hh signaling and their clinical implications.

  5. The Risk Implications of Multinational Enterprise

    DEFF Research Database (Denmark)

    Andersen, Torben Juul

    2011-01-01

    Purpose – Multinational structure has been linked to operational flexibilities that can improve corporate adaptability and a knowledge-based view suggests that multinational resource diversity can facilitate responsive opportunities. The enhanced maneuverability from this can reduce earnings...... volatility and hence the corporate performance risk. But, the internationalization process may also require irreversible investments that increase corporate exposures and leave the risk implications of multinational enterprize somewhat ambiguous. Hence, the purpose of the paper is to present an empirical...... debate about the risk effects of a multinational corporate structure and confirms that a diverse multinational presence is associated with positive risk outcomes. Originality/value – The paper complements a limited number of studies with equivocal results and adopts alternative risk outcome measures...

  6. Legal implications of managed care arrangements.

    Science.gov (United States)

    Knox, W A; Epstein, D M

    1994-09-01

    Prior to the 1980s, managed care was virtually nonexistent as a force in health care. Presently, 64 percent of employees in America are covered by managed care plans, including health maintenance organizations (20 percent) and preferred provider organizations (44 percent). In contrast, only 29 percent of employees were enrolled in managed care plans in 1988 and only 47 percent in 1991. To date, the primary reason for this incredible growth in managed care has been economic-market pressure to reduce health care costs. For the foreseeable future, political pressures are likely to fuel this growth, as managed care is at the center of President Clinton's national health care plan. Although there are numerous legal issues surrounding managed care, this article focuses primarily on antitrust implications when forming managed care entities. In addition, the corporate practice of medicine doctrine, certain tax issues, and the fraud and abuse laws are discussed.

  7. Waste management implications of concentrating slimes

    International Nuclear Information System (INIS)

    The anticipated increase in demand for sand-size tailings from the uranium industry suggests that the fine-grained or 'slime' fraction will require special attention for disposal. The Atomic Energy Control Board (AECB) required information on the behaviour and environmental significance of the fine-grained tailings fraction in disposal facilities. Beak Consultants and Golder Associates were contracted to review the significant characteristics of slimes disposal and prepare a report on the physical and chemical characteristics of fine-grained tailings (Phase 1). This report (Phase 2) presents a summary of disposal and management practices for slimes and outlines potential concerns related to these practices. The report also presents an approach to disposal planning and the implications of available and potential management techniques. Experience with the disposal of uranium slimes is scarce and, therefore, relevant information was borrowed from the other mining sectors to predict the consequences of various disposal scenarios

  8. Racism and cardiovascular disease: implications for nursing.

    Science.gov (United States)

    Jackson, Jennifer; McGibbon, Elizabeth; Waldron, Ingrid

    2013-01-01

    The social determinants of health (SDH) are recognized as a prominent influence on health outcomes across the lifespan. Racism is identified as a key SDH. In this article, the authors describe the concept of racism as an SDH, its impact in discriminatory actions and inactions, and the implications for cardiovascular nurses. Although research in Canada on the links among racism, stress, and cardiovascular disease is limited, there is growing evidence about the stress of racism and its long-term impact on cardiovascular health. The authors discuss how cardiovascular nursing could be enhanced through an understanding of racism-related stress, and race-based differences in cardiovascular care. The authors conclude with strategies for action to address this nursing concern.

  9. The Francis Report--dento-legal implications.

    Science.gov (United States)

    Foster, Martin

    2015-05-01

    This article explores the potential implications of the Francis Report for members of the dental team from a dento-legal perspective. It looks at the broad recommendations in light of the existing ethical environment in which dental registrants work and asks what is new and what the recommendations will actually mean for dental professionals in practical terms. Clinical Relevance: The fundamental recommendations of the Francis Report, namely, that those who provide care should put patients' interests first and be open about outcomes and performance, are not new concepts. A breach of these ethically based expectations may, however, create grounds for legal proceedings, which is clearly a significant point for all members of the dental team. It is therefore important to be aware of what is expected of those providing clinical care.

  10. Interstellar Turbulence II: Implications and Effects

    CERN Document Server

    Scalo, J

    2004-01-01

    Interstellar turbulence has implications for the dispersal and mixing of the elements, cloud chemistry, cosmic ray scattering, and radio wave propagation through the ionized medium. This review discusses the observations and theory of these effects. Metallicity fluctuations are summarized, and the theory of turbulent transport of passive tracers is reviewed. Modeling methods, turbulent concentration of dust grains, and the turbulent washout of radial abundance gradients are discussed. Interstellar chemistry is affected by turbulent transport of various species between environments with different physical properties and by turbulent heating in shocks, vortical dissipation regions, and local regions of enhanced ambipolar diffusion. Cosmic rays are scattered and accelerated in turbulent magnetic waves and shocks, and they generate turbulence on the scale of their gyroradii. Radio wave scintillation is an important diagnostic for small scale turbulence in the ionized medium, giving information about the power spe...

  11. Nursing implications for Hepatic arterial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Nurses working in Nuclear Medicine assist in Hepatic Artery Catheter (HAC) perfusion studies. This scan is not widely performed in Australia, the St George hospital for example performs approximately five per year. The purpose of this article is firstly to review the indications and rationale of HAC patency studies. Secondly, this article will stress the clinical implications for the Nuclear Medicine Nurse during this study. Emphasis will be placed on the importance of patient education during the procedure. A brief overview of hepatic anatomy and the radiopharmaceuticals administered during the scan is discussed. Finally, a step by step protocol is presented to show how the perfusion/ shunt study is performed. Copyright (1999) The Australian and New Zealand Society of Nuclear Medicine Inc

  12. Implications of Orientation in Sheared Cocoa Butter

    Science.gov (United States)

    Guthrie, Sarah E.; Mazzanti, Gianfranco; Marangoni, Alejandro; Idziak, Stefan H. J.

    2004-03-01

    We will present x-ray and mechanical studies of oriented phases of cocoa butter. The structural elements of foods play an important role in determining such things as quality and shelf stability. The specific structure and properties of cocoa butter, however, are complicated due to the ability of the cocoa butter to form crystals in six polymorphic forms. Recent work has shown that the application of shear not only accelerates the transitions to more stable polymorphs, but also causes orientation of the crystallites[1]. The implications of orientation on the structures formed under conditions of shear and cooling will be described using x-ray diffraction and mechanical measurements. 1 G. Mazzanti, S. E. Guthrie, E. B. Sirota et al., Crystal Growth & Design 3 (5), 721 (2003).

  13. Psychoneuroimmune implications of type 2 diabetes: redux.

    Science.gov (United States)

    O'Connor, Jason C; Johnson, Daniel R; Freund, Gregory G

    2009-05-01

    A sizable body of knowledge has arisen demonstrating that type 2 diabetes (T2D) is associated with alterations in the innate immune system. The resulting proinflammatory-leaning imbalance is implicated in the development of secondary disease complications and comorbidities, such as delayed wound healing, accelerated progress of atherosclerosis, and retinopathy, in people who have T2D. New experimental data and the results of recently published health-related quality-of-life surveys indicate that individuals who have T2D experience diminished feelings of happiness, well being, and satisfaction with life. These emotional and psychological consequences of T2D point to altered neuroimmunity as a previously unappreciated complication of T2D. This article discusses recent data detailing the impact of T2D on a person's PNI response. PMID:19389586

  14. Safety implications of self-managed teams

    Energy Technology Data Exchange (ETDEWEB)

    Lardner, R.

    1999-08-01

    This report traces the history of self-management and the reasons for the introduction of self-management. The Health and Safety Executive's approach to management of safety, literature on self-managing teams and safety, and published examples of self-managing teams in the petrochemical industry are discussed. Diagnosing the suitability for self-management, and best practice in implementation are considered, four UK case studies involving the BP Chemicals plant in Baglan Bay, the Shell Exploration and Production Cada Platforms, Industrial Colours Limited, and Amec Process and Energy at Great Yarmouth are given. The research undertaken at BP Oil's Grangemouth refinery on safety implications of self-managed teams is reviewed.

  15. Implications of inherent safe nuclear power system

    International Nuclear Information System (INIS)

    The safety of present day nuclear power reactors and research reactors depends on a combination of design features of passive and active systems, and the alert judgement of their operators. A few inherently safe designs of nuclear reactors for power plants are currently under development. In these designs, the passive systems are emphasized, and the active systems are minimized. Also efforts are made to eliminate the potential for human failures that initiate the series of accidents. If a major system fails in these designs, the core is flooded automatically with coolants that flow by gravity, not by mechanical pumps or electromagnetic actuators. Depending on the choice of the coolants--water, liquid metal and helium gas--there are three principal types of inherently safe reactors. In this paper, these inherently safe reactor designs are reviewed and their implications are discussed. Further, future perspectives of their acceptance by nuclear industries are discussed. (author)

  16. Destination image: Origins, Developments and Implications

    Directory of Open Access Journals (Sweden)

    Sérgio Dominique Ferreira Lopes

    2011-04-01

    Full Text Available Over the last few decades, tourism has become one of the main sectors of the global economy, not only because of its contribution to the Gross Domestic Product (GDP of different countries, but also because of the employment it generates. Since 2009, however, the results of tourism have been severely affected by the economic and financial crisis and it is now essential to analyze the key elements of tourist consumer behavior. In this context, the image that a destination transmits to the market becomes one of the elements which influence tourists the most when choosing a tourist destination. The authors therefore aim to identify the main elements that characterize the image of a tourist destination, as well as their implications for the management of tourist destinations.

  17. Public health implications of altered puberty timing

    DEFF Research Database (Denmark)

    Golub, M.S.; Collman, G.W.; Foster, P.M.;

    2008-01-01

    with an increased risk for testicular cancer according to several, but not all, epidemiologic studies. Girls and, possibly, boys who exhibit premature adrenarche are at a higher risk for developing features of metabolic syndrome, including obesity, type 2 diabetes, and cardiovascular disease later in adulthood......Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early...... sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated...

  18. Clinical Implications of Sarcopenic Obesity in Cancer.

    Science.gov (United States)

    Carneiro, Isabella P; Mazurak, Vera C; Prado, Carla M

    2016-10-01

    Sarcopenia has been associated with several negative clinical outcomes in cancer. However, the consequences of sarcopenic obesity, a condition of combined sarcopenia and obesity burden, have been less extensively investigated. The aim of this paper was to review the current evidence on the prevalence and clinical implications of sarcopenic obesity in cancer. A total of 14 studies linking sarcopenic obesity to a clinical outcome in cancer were included. There is considerable inconsistency in methods used to evaluate body composition as well as in the criteria used to define sarcopenic obesity, which limits comparison among studies. Therefore, the prevalence of sarcopenic obesity varied substantially: between 1 and 29 % in studies including individuals from all body mass index categories and between 15 and 36 % for those including obese individuals only. Negative clinical outcomes reported to be associated with sarcopenic obesity included higher risk of dose-limiting toxicity, surgical complications, physical disability, and shorter survival. PMID:27541923

  19. PRIMARY NURSING IMPLICATIONS ON NURSING CARE ASSISTANCE

    Directory of Open Access Journals (Sweden)

    Luciana Mahnis Pereira Carmona

    2002-06-01

    Full Text Available The authors present the method “Primary Nursing”, which has as principle the elevation of thenurse’s autonomy, in which he is responsible for the patient 24 hours a day. The also present the function of eachnurse engaged in that process, pointing out the advantages of the method and its implications in the practice. In itsreview, they put results of 07 present works accomplished with the introduction of the “Primary Nursing”. As finalconsiderations, the state that the “Primary Nursing” improves the quality of assistance given by the nurse, and itsperformance will mainly depend on the nurse’s interest, on changing the reference system towards the professionalcompetence.

  20. Implications for incorporating simulation in nursing education.

    Science.gov (United States)

    Miller, Shelley

    2010-01-01

    The current intricately complex state of health care holds a multitude of challenges for the novice nurse in acquiring, developing, and maintaining standards of proficiency in clinical practice. This paper will explore the implications or reasons for incorporating simulation in nursing education for two primary reasons. First, simulation is an interactive teaching strategy designed for augmenting the learning process. Simulation is an example of active learning that engages the student to think through a situation then take action through the application of knowledge, and finally to self-reflect during the process of debriefing. Secondly, an increasing number of educational institutions have made the commitment to incorporate simulation technology into nursing curricula. PMID:21175101