Science.gov

Sample records for organophosphorus pesticide residues

  1. COMPARISON OF CHOLINESTERASE ACTIVITY, RESIDUE LEVELS, AND URINARY METABOLITE EXCRETION OF RATS EXPOSED TO ORGANOPHOSPHORUS PESTICIDES

    EPA Science Inventory

    Blood cholinesterase activity, urinary levels of phenolic and organophosphorus metabolites, and residues of intact compounds in blood and fat were determined following exposure of rats to organophosphorus pesticides. The eight pesticides studied included representative halogenate...

  2. Organochlorine and organophosphorus pesticide residues in raw buffalo milk from agroindustrial areas in Assiut, Egypt.

    PubMed

    Shaker, Eman M; Elsharkawy, Eman E

    2015-01-01

    Raw buffalo milk samples from the agroindustrial zone in upper Egypt were analyzed for the presence of organochlorine and organophosphorus pesticides using gas chromatography-mass spectroscopy. Five organochlorine pesticides namely, alachlor, dieldrin, hexachlorobenzene, lindane and methoxychlor and three organophosphorus pesticides chlorpyrifos, malathion, and parathion-methyl were detected in the milk samples. In 44% of the samples, the concentrations of lindane and malathion residues exceeded tolerance levels set by the European Commission (EC) in 2008. In addition, the concentrations of chlorpyrifos, methoxychlor, and hexachlorobenzene residues exceeded the 2008 EC maximum residual limits (MRLs) by 33, 66, and 88% of the examined samples, respectively. However, the levels of alachlor, dieldrin, and parathion-methyl residues were below EC MRLs. The results of this study confirm the risks of pesticide residues exposure that threaten consumer health in Egypt. Thus, we recommend that pesticide residue monitoring programs be instituted in all the developing countries. PMID:25575291

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

    PubMed Central

    Kotinagu, Korrapati; Krishnaiah, Nelapati

    2015-01-01

    Aim: The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of fodder samples of Zone 5 of Musi river showed the residues of dicofol at concentration of 0.07±0.0007 (0.071-0.077). Among organophosphorus compounds, dimetheoate was present in milk samples collected from Zone 6 at a level of 0.13±0.006 (0.111-0.167). The residues of OCPs, OPPs and cyclodies were below the detection limit in the remaining fodder and milk samples collected from Musi river belt in the present study. Conclusion: The results indicate that the pesticide residues in fodder and milk samples were well below the maximum residue level (MRL) values, whereas dicofol in fodder and dimethoate in milk were slightly above the MRL values specified by EU and CODEX. PMID:27047132

  4. IMPROVED SILICA GEL CLEANUP METHOD FOR ORGANOPHOSPHORUS PESTICIDES

    EPA Science Inventory

    Quantitative recovery of some organophosphorus pesticide residues has not been possible with existing silica gel-cleanup procedures. The authors have developed a modification that permits quantitative recovery of all organophosphorus pesticides tested, except those with a carbama...

  5. Organophosphorus pesticide residues in raw milk and infant formulas from Spanish northwest.

    PubMed

    Melgar, M J; Santaeufemia, M; Garcia, M A

    2010-10-01

    Residue levels of seven organophosphorus pesticides (OPPs), widely used as dairy cattle ectoparasiticides or in crops used for animal feed, were determined in raw milk and infant formulas. A total of 312 samples were collected (70 from infant formulas and 242 from raw milk) biweekly during a 24-month period. Pesticides were extracted by means of a solid phase system into acetone. An extract aliquot of acetone was injected into a gas chromatograph (GC) with a nitrogen-phosphorus detector. Recoveries of pesticides spiked in milk samples were 62.2 - 97.2 %. The frequency of total samples containing detectable levels of OPP residues was 6.73 % in total milk and 8.67 % in raw milk. The highest percentage incidence measured was for dichlorvos (5.78 %), followed by coumaphos (2.06 %), and parathion methyl (0.83 %). The range of positive results was calculated to be between 0.005 and 0.220 mg kg(- 1). No residue was detected in the final product (infant formulas), so any risk to consumer health, especially to children's health, would be limited. PMID:20803361

  6. The research of Organophosphorus pesticide biosensor characteristic

    NASA Astrophysics Data System (ADS)

    Peng, Yong; Luo, Xixian; Cheng, Yi

    2010-10-01

    To study the fiber-sensor film applied in detecting Organophosphorus pesticide, methyltriethoxysilane was used as precursor, which was doped by FITC- AchE. Consequently, the excellent Acetylcholinesterase biology sensitivity film was prepared. Physics characteristic of the film and sensitivity of Organophosphorus pesticide were researched. In organophosphorus pesticide residue testing, the experimental results indicated that the linear measurement range could reach 10-7{10-6 mol/L, moreover the detection limit is 10-8 mol/L. The sensor could be applied in biological / chemical research, clinical medicine, environmental protection, food inspection, biochemical preventive war field and so on.

  7. [Contamination of Organophosphorus Pesticides Residue in Fresh Vegetables and Related Health Risk Assessment in Changchun, China].

    PubMed

    Yu, Rui; Liu, Jing-shuang; Wang, Qi-cun; Liu, Qiang; Wang, Yang

    2015-09-01

    This study aims to investigate the concentrations of organophosphorus pesticides (OPs) in fresh vegetables. A total of Z14 samples from seven types of vegetables were collected from the suburb in Changchun City. The OPs were analyzed by gas chromatography coupled with flame photometric detector (GC-FPD). Target hazard quotients (THQ) were applied to estimate the potential health risk to inhabitants. Results showed that OPs concentrations exceeded the Maximum Residue Limit (MRL) in more than 23. 4% samples, and were not detected in only 7. 9% samples. Detection rates of OPs was as follow in the decreased order: diazinon (82. 2%) > phorate (45. 8%) > dimethoate (29. 4%) > parathion-methyl (27. 6%) > omethoate (23. 8%) > dichlorvos (22. 9%) > fenitrothion (21%) > fenthion (18. 7%) > parathion (18. 2%) > methamidophos (17. 3%) > malathion (12. 1%). The percentages above MRL for leaves were higher than for non-leafy vegetables. The order of percentages of OPs above MRL was as follows: green onion (82. 5%) > radish (37. 5%) > red pepper (17. 2%) > Chinese vegetable (14. 3%) > cucumber (3. 2%) > eggplant (2. 9%) > tomato (0%). 49. 5% vegetables samples showed more than one OP. The average target hazard quotients (ave THQ) were all less than one and the average Hazard Index (ave HI) was 0. 462, so that inhabitants who expose average OP levels may not experience adverse health effects. PMID:26717714

  8. Qualitative and quantitative analysis of organophosphorus pesticide residues using temperature modulated SnO(2) gas sensor.

    PubMed

    Huang, Xingjiu; Liu, Jinhuai; Pi, Zongxin; Yu, Zengliang

    2004-10-01

    Qualitative and quantitative analysis of organophosphorus pesticide residues (acephate and trichlorphon) using temperature modulated SnO(2) gas sensor were studied. The testing method employed only a single SnO(2)-based gas sensor in a rectangular temperature mode to perform the qualitative analysis of pure pesticide vapor and a binary vapor mixture in the air. Experimental results showed that in the range 250-300 degrees C and at the modulating frequency of 20mHz the high selectivity of the sensor could be achieved. The quantitative analysis of the pure pesticide vapor and their mixture were performed by fast Fourier transformation (FFT). The higher harmonics of the FFT characterized the non-linear properties of the response at the sensor surface. The amplitudes of the higher harmonics exhibited characteristic variations that depend on the concentration and the kinetics of pesticide species on the sensor surface. PMID:18969637

  9. Detection of residual organochlorine and organophosphorus pesticides in agricultural soil in Rio Verde region of San Luis Potosi, Mexico.

    PubMed

    Velasco, Antonio; Hernández, Sergio; Ramírez, Martha; Ortíz, Irmene

    2014-01-01

    Organochlorine pesticides were intensively used in Mexico from 1950 until their ban and restriction in 1991. However, the presence of these compounds is commonly reported in many regions of the country. The aim of the present study was to identify and quantify residual organochlorine and organophosphorus pesticides in agricultural soil in Rio Verde region, San Luis Potosi state, which has been identified as possibly polluted by pesticides. Composed samples from 24 zones covering an area of approximately 5,440 ha were analyzed. The most frequently found pesticides were p,p'-DDT followed by ,p,p'-DDE, heptachlor, endosulfan and γ-HCH whose frequency rates were 100, 91, 83 and 54%, respectively. The concentration of p,p'-DDT in the crops grown in these soils was in the following order: chili > maize > tomato > alfalfa. The results obtained in this study show that p,p'-DDT values are lower or similar to those found in other agricultural regions of Mexico. Methyl and ethyl parathion were the most frequent organophosphate pesticide detected in 100% and 62.5% of the samples with average concentrations of 25.20 and 47.48 μg kg(-1), respectively. More research is needed to establish the background levels of pesticides in agricultural soils and their potential ecological and human health effects in this region. PMID:24813984

  10. Study on Carrier Material of Immobilization Acetylcholinesterase For Biosensor in Detectionof Organophosphorus Pesticide Residues

    NASA Astrophysics Data System (ADS)

    Sun, Xia; Wang, Xiangyou; Jia, Chuandong

    A comparison between several immobilization materials of AChE on surface of glassy carbon electrode(GCE) was presented. The immobilization methods employed crosslinking method with glutaraldehyde as a cross-linking agent and bovine serum albumin(BSA) as a protectant, AChE was immobilized on different membranes including nylon membrane, cellulose nitrate membrane and chitosan membrane respectively. The enzyme membrane was then fixed on the surface of glassy carbon electrode(GCE) with O-ring to prepare an amperometric biosensor for the detection of organophosphorus pesticides. The activity of immobilization AChE was detected by measuring the oxidation current of thiocholine, the results showed that the activity of immobilization AChE were all different with different membrane as carrier material.Compared with nylon membrane and cellulose nitrate membrane, chitosan membrane was obviously good. So chitosan membrane can be selected as immobilized AChE carrier material.

  11. Risk assessment of the cumulative acute exposure of Hungarian population to organophosphorus pesticide residues with regard to consumers of plant based foods.

    PubMed

    Zentai, Andrea; Szabó, István J; Kerekes, Kata; Ambrus, Árpád

    2016-03-01

    Based on the Hungarian pesticide residues monitoring data of the last five years and the consumption data collected within a 3-day dietary record survey in 2009 (more than 2 million pesticide residue results and almost 5000, 0-101-year-old consumers 3 non-consecutive-day personal fruit and vegetable consumption data), the cumulative acute exposure of organophosphorus pesticide residues was evaluated. The relative potency factor approach was applied, with acephate chosen as index compound. According to our conservative calculation method, applying the measured residues only, the 99.95% of the 99th percentiles of calculated daily intakes was at or below 87 μg/kgbwday, indicating that the cumulative acute exposure of the whole Hungarian population (including all age classes) to organophosphorus compounds was not a health concern. PMID:26807885

  12. An Innovative Rapid Method for Analysis of 10 Organophosphorus Pesticide Residues in Wheat by HS-SPME-GC-FPD/MSD.

    PubMed

    Du, Xin; Ren, YongLin; Beckett, Stephen J

    2016-03-01

    The rapid detection of pesticide residues in wheat has become a top food security priority. A solvent-free headspace solid-phase microextraction (HS-SPME) has been evaluated for rapid screening of organophosphorus pesticide (OPP) residues in wheat with high sensitivity. Individual wheat samples (1.7 g), spiked with 10 OPPs, were placed in a 4 mL sealed amber glass vial and heated at 60°C for 45 min. During this time, the OPP residues were extracted with a 50 μm/30 μm divinylbenzene (DVB)/carboxen (CAR)/plasma desorption mass spectroscopy polydimethylsiloxane (PDMS) fiber from the headspace above the sample. The fiber was then removed and injected into the GC injection port at 250°C for desorption of the extracted chemicals. The multiple residues were identified by a GC mass spectrometer detector (GC-MSD) and quantified with a GC flame photometric detector (GC-FPD). Seven spiked levels of 10 OPPs on wheat were analyzed. The GC responses for a 50 μm/30 μm DVB/CAR/PDMS fiber increased with increasing spiking levels, yielding significant (R(2) > 0.98) linear regressions. The lowest LODs of the multiple pesticide standards were evaluated under the conditions of the validation study in a range of levels from 0 (control) to 100 ng of pesticide residue per g of wheat that separated on a low-polar GC capillary column (Agilent DB-35UI). The results of the HS-SPME method were compared with the QuEChERS AOAC 2007.01 method and they showed several advantages over the latter. These included improved sensitivity, selectivity, and simplicity. PMID:26964527

  13. Organophosphorus pesticide residues in vegetables from farms, markets, and a supermarket around Kwan Phayao Lake of Northern Thailand.

    PubMed

    Sapbamrer, Ratana; Hongsibsong, Surat

    2014-07-01

    This study investigated organophosphorus (OP) residues in vegetables from 27 farms, 106 markets, and 1 supermarket around Kwan Phayao Lake, Northern Thailand, between August and September 2013. Types of vegetables sampled were all vegetables cultivated or sold around the study site. The most common OP pesticides detected in farm samples were chlorpyrifos (50 %), malathion (31.8 %), monocrotophos (31.8 %), diazinon (13.6 %), omethoate (13.6 %), and dicrotophos (9.1 %). The most common OP pesticides detected in market samples were chlorpyrifos (33.9 %), diazinon (18.6 %), parathion-methyl (3.4 %), profenofos (3.4 %), primiphos-ethyl (3.4 %), and fenitrothion (1.7 %). The OP pesticides detected in supermarket samples were chlorpyrifos (33.3 %), and diazinon (66.7 %). Among the compounds detected, chlorpyrifos was detected in most of the vegetable samples from all sources. The highest chlorpyrifos level in farm samples were found in lemon balm (2.423 mg/kg) followed by Vietnamese coriander (0.835 mg/kg), and cowpea (0.027 mg/kg). The highest level in markets samples were found in garlic (7.785 mg/kg) followed by Chinese cabbage (2.864 mg/kg) and Vietnamese coriander (1.308 mg/kg). Residues from supermarket samples were found only in parsley (0.027 mg/kg). The findings showed that 16 samples (59.3 %) from farms and 14 samples (13.2 %) from markets contained OP residues at or above the maximum residue limits established by the European Union. It is concluded that awareness, safety education, and strict regulation of pesticide use are necessary. PMID:24609615

  14. ORGANIC COMPOUNDS IN ORGANOPHOSPHORUS PESTICIDE MANUFACTURING WASTEWATERS

    EPA Science Inventory

    Preliminary survey information on the organophosphorus pesticide industry wastewater streams and analytical methods to monitor levels of organic compounds present in these streams are presented. The identification and quantification of organophosphorus compounds was emphasized, b...

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

    PubMed Central

    Chowdhury, Md. Alamgir Zaman; Banik, Sanjoy; Uddin, Borhan; Moniruzzaman, Mohammed; Karim, Nurul; Gan, Siew Hua

    2012-01-01

    Several types of organophosphorous and carbamate pesticides have been used extensively by the farmers in Bangladesh during the last few decades. Twenty seven water samples collected from both paddy and vegetable fields in the Savar and Dhamrai Upazilas in Bangladesh were analyzed to determine the occurrence and distribution of organo-phosphorus (chlorpyrifos, malathion and diazinon) and carbamate (carbaryl and carbofuran) pesticide residues. A high performance liquid chromatograph instrument equipped with a photodiode array detector was used to determine the concentrations of these pesticide residues. Diazinon and carbofuran were detected in water samples collected from Savar Upazila at 0.9 μg/L and 198.7 μg/L, respectively. Malathion was also detected in a single water sample at 105.2 μg/L from Dhamrai Upazila. Carbaryl was the most common pesticide detected in Dhamrai Upazila at 14.1 and 18.1 μg/L, while another water sample from Dhamrai Upazila was contaminated with carbofuran at 105.2 μg/L. Chlorpyrifos was not detected in any sample. Overall, the pesticide residues detected were well above the maximum acceptable levels of total and individual pesticide contamination, at 0.5 and 0.1 μg/L, respectively, in water samples recommended by the European Economic Community (Directive 98/83/EC). The presence of these pesticide residues may be attributed by their intense use by the farmers living in these areas. Proper handling of these pesticides should be ensured to avoid direct or indirect exposure to these pesticides. PMID:23202689

  16. Dissipation behavior of organophosphorus pesticides during the cabbage pickling process: residue changes with salt and vinegar content of pickling solution.

    PubMed

    Lu, Yuele; Yang, Zhonghua; Shen, Luyao; Liu, Zhenmin; Zhou, Zhiqiang; Diao, Jinling

    2013-03-01

    In this experiment, the behavior of 10 pesticides in three different cabbage pickling treatments has been studied. The brine used for pickling was made up with different salt and vinegar contents to determine the influence of different pickling solutions on pesticide dissipation and distribution. A modified QuECHERS and SPE method was established for the analysis of the pesticides in the cabbage and brine. It was found that different pesticides showed different dissipation patterns and finally represented dissimilar residue levels in the cabbage and brine. Statistical analysis was performed to compare the distinctions of these pesticides between each treatment and proved that salt content and pH value had certain influence on the dissipation and distribution of these pesticides during the pickling process. The data from this experiment would help to control pesticide residues in pickled cabbage and prevent potential risk to human health and environmental safety. PMID:23402557

  17. [High throuput analysis of organophosphorus pesticide residues and their metabolites in animal original foods by dual gas chromatography-dual pulse flame photometric detection].

    PubMed

    Yang, Lixin; Li, Heli; Miao, Hong; Zeng, Fangang; Li, Ruifeng; Chen, Huijing; Zhao, Yunfeng; Wu, Yongning

    2011-10-01

    A method was established for the quantitative determination of 54 organophosphorus pesticide residues and their metabolites in foods of animal origin by dual gas chromatography-dual pulse flame photometric detection. Homogenized samples were extracted with acetone and methylene chloride, and cleaned-up by gel permeation chromatography (GPC). The response of each analyte showed a good linearity with a correlation coefficient not less than 0. 99. The recovery experiments were performed by a blank sample spiked at low, medium and high fortification levels. The recoveries for beef, mutton, pork, chicken were in the range of 50. 5% -128. 1% with the relative standard deviations (n = 6) of 1. 1% -25. 5%, which demonstrated the good precision and accuracy of the present method. The limits of detection for the analytes were in the range of 0. 001 -0. 170 mg/kg, and the limits of quantification were in the range of 0. 002 -0. 455 mg/kg. Animal food samples collected from markets such as meat, liver and kidney were analyzed, and the residues of dichlorovos and disulfoton-sulfoxide were found in the some samples. The established method is sensitive and selective enough to detect organophosphorus pesticide residues in animal foods. PMID:22268359

  18. Use of graphitic carbon black and primary secondary amine for determination of 17 organophosphorus pesticide residues in spinach.

    PubMed

    Li, Li; Li, Wei; Ge, Jing; Wu, Yijun; Jiang, Shuren; Liu, Fengmao

    2008-10-01

    Graphitized carbon black (GCB) and primary secondary amine (PSA) as dispersive-SPE sorbents were applied to optimize the method for the determination of 17 organophosphorus pesticides in spinach which contained so many pigments using GC with flame photometric detector (FPD). The sample was extracted with ACN, and an aliquot of the extract was concentrated to near dryness. Ethyl acetate or acetone was chosen as the dissolving solvent. Subsequently, dispersive-SPE was used for cleanup, and the type and quantity of sorbents (GCB, PSA and activated carbon) were tested in the experiments. The best results were when acetone was used to dissolve and 30 mg each of GCB and PSA for cleanup. In this condition, recoveries of pesticides analyzed were between 52-117% with RSD below 10%, and LOQ ranged from 10 to 20 microg/kg. This method was simple, effective and efficient, and can protect the GC system to some extent. PMID:18972520

  19. CUMULATIVE RISK ANALYSIS FOR ORGANOPHOSPHORUS PESTICIDES

    EPA Science Inventory

    Cumulative Risk Analysis for Organophosphorus Pesticides
    R. Woodrow Setzer, Jr. NHEERL MD-74, USEPA, RTP, NC 27711

    The US EPA has recently completed a risk assessment of the effects of exposure to 33 organophosphorous pesticides (OPs) through the diet, water, and resi...

  20. Pesticides.

    ERIC Educational Resources Information Center

    Sherma, Joseph

    1989-01-01

    This review is devoted to methods for the determination of residues of pesticides and some related industrial chemicals. Topics include: residue methods, sampling, chromatography, organochlorine pesticides, organophosphorus pesticides, carbamate insecticides, herbicides, fungicides, pyrethrins, fumigants, and related chemicals. (MVL)

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

    PubMed

    Sarkhail, Parisa; Yunesian, Masud; Ahmadkhaniha, Reza; Sarkheil, Pantea; Rastkari, Noushin

    2012-01-01

    The frequent occurrence of pesticide residues in herbal materials was indicated by previous studies. In this study, the concentration of some of the organophosphorus pesticides including parathion, malathion, diazinon and pirimiphos methyl in different kinds of medicinal plants were determined. The samples were collected randomly from ten local markets of different areas of Iran. At the detection limit of 0.5 ng g-1, parathion and pirimiphos methyl were not detected in any of the samples. Some amounts of malathion and diazinon were found in Zataria, Matricaria chamomile, Spearmint and Cumin Seed samples while, the concentrations of target organophosphorus pesticides in Borage samples were below the detection limits of the methods which could be a result of intensive transformation of organophosphorus pesticides by Borage. In addition the organophosphorus pesticides were detected in all of the samples below the maximum residue levels (MRLs) proposed by the international organizations. PMID:23351610

  2. CUMULATIVE EFFECTS OF ORGANOPHOSPHORUS OR CARBAMATE PESTICIDES.

    EPA Science Inventory

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

  3. Determination of 49 organophosphorus pesticide residues and their metabolites in fish, egg, and milk by dual gas chromatography-dual pulse flame photometric detection with gel permeation chromatography cleanup.

    PubMed

    Yang, Lixin; Li, Heli; Zeng, Fangang; Liu, Yinping; Li, Ruifeng; Chen, Huijing; Zhao, Yunfeng; Miao, Hong; Wu, Yongning

    2012-02-29

    A new method for the quantitative determination of 49 kinds of organophosphorus pesticide residues and their metabolites in fish, egg, and milk by dual gas chromatography-dual pulse flame photometric detection was developed. Homogenized samples were extracted with acetone and methylene chloride (1 + 1, v/v), and then the extracts were cleaned up by gel permeation chromatography (GPC). The response of each organophosphorus pesticide showed a good linearity with its concentration; the linearity correlation was not less than 0.99. The detection limits (S/N = 3) of pesticides were in the range of 0.001-0.025 mg kg⁻¹. The recovery experiments were performed by blank sample spiked at low, medium, and high fortification levels. The recoveries for fish, egg, and milk were 50.9-142.2, 53.3-137.2, and 50.3-139.4% with relative standard deviations (RSD, n = 6) of 2.3-24.9, 4.3-26.7, and 2.8-32.2%, respectively. The method was applied to detect organophosphorus pesticides in samples collected from the market, and satisfactory results were obtained. This quantitative method was highly sensitive and exact and could be applied to the accurate determination of organophosphorus contaminants in fish, egg, and milk. PMID:22300587

  4. Chlorination of organophosphorus pesticides in natural waters.

    PubMed

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

    2008-05-01

    Unknown second-order rate constants for the reactions of three organophosphorus pesticides (chlorpyrifos, chlorfenvinfos and diazinon) with chlorine were determined in the present study, and the influence of pH and temperature was established. It was found that an increase in the pH provides a negative effect on the pesticides degradation rates. Apparent second-order rate constants at 20 degrees C and pH 7 were determined to be 110.9, 0.004 and 191.6 M(-1) s(-1) for chlorpyrifos, chlorfenvinfos and diazinon, respectively. A higher reactivity of chlorine with the phosphorothioate group (chlorpyrifos and diazinon) than with the phosphate moiety (chlorfenvinfos) could explain these results. Intrinsic rate constant for the elementary reactions of chlorine species with chlorpyrifos and diazinon were also calculated, leading to the conclusion that the reaction between hypochlorous acid and the pesticide is predominant at neutral pH. The elimination of these pesticides in surface waters was also investigated. A chlorine dose of 2.5 mg L(-1) was enough to oxidize chlorpyrifos and diazinon almost completely, with a formation of trihalomethanes below the EU standard for drinking water. However, the removal of chlorfenvinfos was not appreciable. Therefore, chlorination is a feasible option for the removal of organophosphorus pesticides with phosphorothioate group during oxidation and disinfection processes, but not for the elimination of pesticides with phosphate moiety. PMID:17904287

  5. Biodegradation of organophosphorus pesticides by soil bacteria

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

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

  6. ORGANOPHOSPHORUS PESTICIDE DEGRADATION PATHWAYS DURING DRINKING WATER TREATMENT

    EPA Science Inventory

    The objective of this work was to investigate organophosphorus (OP) pesticide transformation pathways as a class in the presence of aqueous chlorine. Seven priority OP pesticides were examined for their reactivity with aqueous chlorine: chlorpyrifos (CP), parathion (PA), diazino...

  7. Application of elevated temperature-dispersive liquid-liquid microextraction for determination of organophosphorus pesticides residues in aqueous samples followed by gas chromatography-flame ionization detection.

    PubMed

    Farajzadeh, Mir Ali; Afshar Mogaddam, Mohammad Reza; Rezaee Aghdam, Samaneh; Nouri, Nina; Bamorrowat, Mahdi

    2016-12-01

    In the present study, an elevated temperature, dispersive, liquid-liquid microextraction/gas chromatography-flame ionization detection was investigated for the determination, pre-concentration, and extraction of six organophosphorus pesticides (malathion, phosalone, dichlorvos, diazinon, profenofos, and chlorpyrifos) residues in fruit juice and aqueous samples. A mixture of 1,2-dibromoethane (extraction solvent) and dimethyl sulfoxide (disperser solvent) was injected rapidly into the sample solution heated at an elevated temperature. Analytical parameters, including enrichment factors (1600-2075), linearity (r>0.994), limits of detection (0.82-2.72ngmL(-1)) and quantification (2.60-7.36ngmL(-1)), relative standard deviations (<7%) and extraction recoveries (64-83%), showed the high efficiency of the method developed for analysis of the target analytes. The proposed procedure was used effectively to analyse selected analytes in river water and fruit juice, and diazinon was found at ngmL(-1) concentrations in apple juice. PMID:27374524

  8. [Evaluation of QuEchERS methods for the analysis of 66 organophosphorus pesticide residues in vegetables by liquid chromatography-tandem mass spectrometry].

    PubMed

    Wang, Lianzhu; Zhou, Yu; Chen, Yong; Wang, Ruilong; Lin, Zixu; Lin, Dejuan; Zheng, Shaohui

    2012-02-01

    A comparison was made between the two versions of QuEChERS sample preparation method for the extraction of 66 organophosphorus pesticides (OPPS) in vegetables. The two QuEChERS methods were the original method without buffer published in 2003, and the AOAC Official Method 2007. 01 with acetate buffer. The adsorption behaviors of primary secondary amine (PSA) sorbent and C18 sorbent on the OPPS were studied. The method of after-extraction addition was used to evaluate matrix effects for OPPS in matrix of broccoli, tomato, green soybean, radish and shallot during liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. As a result, the QuEChERS method with acetate buffer gave higher and more consistent recoveries for some of OPPS. The PSA sorbent and C18 sorbent can adsorb dibrom, so the QuEChERS method was not suitable for the analysis of dibrom. The maximum matrix effects were in the extracts of broccoli during LC-MS/MS analysis. In this article, OPPS were extracted using the QuEChERS method with acetate buffer, and analysed by LC-MS/MS under the optimized conditions with monitoring 132 MS/MS transitions of precursor ions (two for each pesticide) in one single run. Recoveries for all but dibrom at fortification levels of 10, 40, 80 microg/kg in broccoli, tomato, green soybean, radish and shallot ranged from 55% to 122% with relative standard deviations of 1.6% - 18%. The limits of quantification (S/N > or = 10) were 0.1 - 8 microg/kg. Based on these results, the analytical method was proven to be highly efficient, robust and sensitive, and suitable for the monitoring of the maximum residue limits (MRLs) of 66 OPPS in vegetables. PMID:22679828

  9. Analysis of eight organophosphorus pesticide residues in fresh vegetables retailed in agricultural product markets of Nanjing, China.

    PubMed

    Wang, Ligang; Liang, Yongchao; Jiang, Xin

    2008-10-01

    A method to effectively remove pigments in fresh vegetables using activated carbon followed cleanup through solid phase extraction (SPE) cartridge to further reduce matrix interference and contamination, was established to determine eight organophosphorous pesticides (OPPs) by gas chromatography (GC) with nitrogen-phosphorus detection (NPD) in this study, and it has been successfully applied for the determination of eight OPPs in various fresh vegetables with the recoveries ranging from 61.8% to 107%. To evaluate eight OPPs residue level, some fresh vegetables retailed at three agricultural product markets (APM) of Nanjing in China were detected, the results showed that phorate in Shanghai green (0.0257 microg g(-1)) and Chinese cabbage (0.0398 microg g(-1)), dimethoate in Shanghai green (0.0466-0.0810 microg g(-1)), Chinese cabbage (0.077 microg g(-1)), and spinach (0.118-0.124 microg g(-1)), methyl-parathion in Shanghai green (0.0903 microg g(-1)), Chinese cabbage (0.157 microg g(-1)), and spinach (0.0924 microg g(-1)), malathion in Shanghai green (0.0342-0.0526 microg g(-1)), chorpyrifos in spinach (0.106-0.204 microg g(-1)), and Chinese cabbage (0.149 microg g(-1)), chlorfenvinfos in carrot (0.094-0.131 microg g(-1)), were found. However, fonofos and fenthion were not detected in all the collected vegetable samples. PMID:18651087

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

    PubMed

    Jensen, A F; Petersen, A; Granby, K

    2003-08-01

    The aim of the study is to evaluate the potential cumulative effects of organophosphorus and carbamate pesticides that act through a common mechanism of toxicity, and to assess the long- and short-term risks for the Danish population. The intake estimates are based on dietary intake data collected in the Danish nation-wide food consumption survey in 1995. The pesticide data are based on the Danish pesticide residue-monitoring programme from 1996-2001. The amount of 35 organophosphorus pesticides and carbamates were included in the cumulative risk assessment. Processing factors, such as reduction of pesticide levels by rinsing and peeling, were applied in the exposure assessment. The "Toxicity Equivalence Factor" (TEF) approach was used to normalise the toxicity of the different organophosphorus and carbamate pesticides. Cumulative chronic exposure of organophosphorus and carbamates pesticides via fruit, vegetables and cereals is for adults 0.8-2% of the Acceptable Daily Intake (ADI) in chlorpyrifos equivalents, and 0.03-11% of the ADI in methamidophos equivalents; and for children 2-5% of the ADI in the chlorpyrifos equivalents, and 0.07-27% of the ADI in methamidophos equivalents. Neither Acute Reference Dose (ARfD) nor ADI was exceeded for any of the compounds studied. The results indicate that the Danish population is neither exposed to any cumulative chronic risk, nor at risk of acute exposure, from consumption of organophosphorus and carbamate pesticides from fruit, vegetables and cereals. PMID:13129794

  11. Fluorescent Chemosensors for Toxic Organophosphorus Pesticides: A Review

    PubMed Central

    Obare, Sherine O.; De, Chandrima; Guo, Wen; Haywood, Tajay L.; Samuels, Tova A.; Adams, Clara P.; Masika, Noah O.; Murray, Desmond H.; Anderson, Ginger A.; Campbell, Keith; Fletcher, Kenneth

    2010-01-01

    Many organophosphorus (OP) based compounds are highly toxic and powerful inhibitors of cholinesterases that generate serious environmental and human health concerns. Organothiophosphates with a thiophosphoryl (P=S) functional group constitute a broad class of these widely used pesticides. They are related to the more reactive phosphoryl (P=O) organophosphates, which include very lethal nerve agents and chemical warfare agents, such as, VX, Soman and Sarin. Unfortunately, widespread and frequent commercial use of OP-based compounds in agricultural lands has resulted in their presence as residues in crops, livestock, and poultry products and also led to their migration into aquifers. Thus, the design of new sensors with improved analyte selectivity and sensitivity is of paramount importance in this area. Herein, we review recent advances in the development of fluorescent chemosensors for toxic OP pesticides and related compounds. We also discuss challenges and progress towards the design of future chemosensors with dual modes for signal transduction. PMID:22163587

  12. Fluorescent chemosensors for toxic organophosphorus pesticides: a review.

    PubMed

    Obare, Sherine O; De, Chandrima; Guo, Wen; Haywood, Tajay L; Samuels, Tova A; Adams, Clara P; Masika, Noah O; Murray, Desmond H; Anderson, Ginger A; Campbell, Keith; Fletcher, Kenneth

    2010-01-01

    Many organophosphorus (OP) based compounds are highly toxic and powerful inhibitors of cholinesterases that generate serious environmental and human health concerns. Organothiophosphates with a thiophosphoryl (P=S) functional group constitute a broad class of these widely used pesticides. They are related to the more reactive phosphoryl (P=O) organophosphates, which include very lethal nerve agents and chemical warfare agents, such as, VX, Soman and Sarin. Unfortunately, widespread and frequent commercial use of OP-based compounds in agricultural lands has resulted in their presence as residues in crops, livestock, and poultry products and also led to their migration into aquifers. Thus, the design of new sensors with improved analyte selectivity and sensitivity is of paramount importance in this area. Herein, we review recent advances in the development of fluorescent chemosensors for toxic OP pesticides and related compounds. We also discuss challenges and progress towards the design of future chemosensors with dual modes for signal transduction. PMID:22163587

  13. Chloramination of Organophosphorus Pesticides Found in Drinking Water Sources

    EPA Science Inventory

    The degradation of commonly detected organophosphorus (OP) pesticides, in drinking water sources, was investigated under simulated chloramination conditions. Due to monochloramine autodecomposition, it is difficult to observe the direct reaction of monochloramine with each OP pe...

  14. Development of green onion and cabbage certified reference materials for quantification of organophosphorus and pyrethroid pesticides.

    PubMed

    Otake, Takamitsu; Yarita, Takashi; Aoyagi, Yoshie; Kuroda, Youko; Numata, Masahiko; Iwata, Hitoshi; Mizukoshi, Kazushi; Nakamura, Munetomo; Watai, Masatoshi; Mitsuda, Hitoshi; Fujikawa, Takashi; Ota, Hidekazu

    2011-08-24

    Green onion and cabbage certified reference materials for the analysis of pesticide residues were issued by the National Metrology Institute of Japan, part of the National Institute of Advanced Industrial Science and Technology. Green onion and cabbage samples were grown so as to contain several kinds of organophosphorus and pyrethroid pesticides, and those were collected from a field in the Kochi Prefecture in Japan. The certification was carried out by using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides (diazinon, fenitrothion, cypermethrin, etofenprox, and permethrin for green onion and chlorpyrifos, fenitrothion, and permethrin for cabbage) were obtained by isotope dilution mass spectrometry. Certified values of target pesticides were 0.96-13.9 and 2.41-6.9 mg/kg for green onion and cabbage, respectively. These are the first green onion and cabbage powder certified reference materials in which organophosphorus and pyrethroid pesticides are determined. PMID:21774469

  15. Wildlife mortality attributed to organophosphorus and carbamate pesticides

    USGS Publications Warehouse

    Glaser, L.C.

    1995-01-01

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

  16. Enzyme-based electrochemical biosensors for determination of organophosphorus and carbamate pesticides

    SciTech Connect

    Everett, W.R.; Rechnitz, G.A.

    1999-01-01

    A mini review of enzyme-based electrochemical biosensors for inhibition analysis of organophosphorus and carbamate pesticides is presented. Discussion includes the most recent literature to present advances in detection limits, selectivity and real sample analysis. Recent reviews on the monitoring of pesticides and their residues suggest that the classical analytical techniques of gas and liquid chromatography are the most widely used methods of detection. These techniques, although very accurate in their determinations, can be quite time consuming and expensive and usually require extensive sample clean up and pro-concentration. For these and many other reasons, the classical techniques are very difficult to adapt for field use. Numerous researchers, in the past decade, have developed and made improvements on biosensors for use in pesticide analysis. This mini review will focus on recent advances made in enzyme-based electrochemical biosensors for the determinations of organophosphorus and carbamate pesticides.

  17. Validation and use of a fast sample preparation method and liquid chromatography-tandem mass spectrometry in analysis of ultra-trace levels of 98 organophosphorus pesticide and carbamate residues in a total diet study involving diversified food types.

    PubMed

    Chung, Stephen W C; Chan, Benny T P

    2010-07-16

    This paper reports a comprehensive sensitive multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection, identification and quantitation of 73 pesticides and their related products, a total of 98 analytes, belonging to organophosphorus pesticides (OPPs) and carbamates, in foods. The proposed method makes use of a modified QuEChERS (quick, easy, cheap, effective, rigged, and safe) procedure that combines isolation of the pesticides and sample clean-up in a single step. Analysis is performed by liquid chromatography-electrospray ionization-tandem mass spectrometry operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. Two main fragment ions for each pesticide were obtained to achieve the identification according to the SANCO guidelines 10684/2009. The method was validated with various food samples, including edible oil, meat, egg, cheese, chocolate, coffee, rice, tree nuts, citric fruits, vegetables, etc. No significant matrix effect was observed for tested pesticides, therefore, matrix-matched calibration was not necessary. Calibration curves were linear and covered from 1 to 20 microg L(-1) for all compounds studied. The average recoveries, measured at 10 microg kg(-1), were in the range 70-120% for all of the compounds tested with relative standard deviations below 20%, while a value of 10 microg kg(-1) has been established as the method limit of quantitation (MLOQ) for all target analytes. Similar trueness and precision results were also obtained for spiking at 200 microg kg(-1). Expanded uncertainty values were in the range 21-27% while the HorRat ratios were below 1. The method has been successfully applied to the analysis of 700 food samples in the course of a baseline monitoring study of OPPs and carbamates. PMID:20557892

  18. Sorption of triazine and organophosphorus pesticides on soil and biochar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although a large number of reports are available on sorption and degradation of triazine and organophosphorus pesticides in soils, systematic studies are lacking to directly compare and predict the fate of agrochemicals having different susceptibilities for hydrolysis and other degradation pathways....

  19. Development, validation, and uncertainty measurement of multi-residue analysis of organochlorine and organophosphorus pesticides using pressurized liquid extraction and dispersive-SPE techniques.

    PubMed

    Sanyal, Doyeli; Rani, Anita; Alam, Samsul; Gujral, Seema; Gupta, Ruchi

    2011-11-01

    Simple and efficient multi-residue analytical methods were developed and validated for the determination of 13 organochlorine and 17 organophosphorous pesticides from soil, spinach and eggplant. Techniques namely accelerated solvent extraction and dispersive SPE were used for sample preparations. The recovery studies were carried out by spiking the samples at three concentration levels (1 limit of quantification (LOQ), 5 LOQ, and 10 LOQ). The methods were subjected to a thorough validation procedure. The mean recovery for soil, spinach and eggplant were in the range of 70-120% with median CV (%) below 10%. The total uncertainty was evaluated taking four main independent sources viz., weighing, purity of the standard, GC calibration curve and repeatability under consideration. The expanded uncertainty was well below 10% for most of the pesticides and the rest fell in the range of 10-20%. PMID:21210211

  20. Particulate matter formation from photochemical degradation of organophosphorus pesticides

    NASA Astrophysics Data System (ADS)

    Borrás, E.; Ródenas, M.; Vera, T.; Muñoz, A.

    2015-12-01

    Several experiments were performed in the European Photo-reactor - EUPHORE - for studying aerosol formation from organophosphorus pesticides such as diazinon, chlorpyrifos, chlorpyrifos-methyl and pirimiphos-methyl. The mass concentration yields obtained (Y) were in the range 5 - 44% for the photo-oxidation reactions in the presence and the absence of NOx. These results confirm the importance of studying pesticides as significant precursors of atmospheric particulate matter due to the serious risks associated to them. The studies based on the use of EUPHORE photoreactor provide useful data about atmospheric degradation processes of organophosphorus pesticides to the atmosphere. Knowledge of the specific degradation products, including the formation of secondary particulate matter, could complete the assessment of their potential impact, since the formation of those degradation products plays a significant role in the atmospheric chemistry, global climate change, radiative force, and are related to health effects.

  1. Vortex-assisted low density solvent liquid-liquid microextraction and salt-induced demulsification coupled to high performance liquid chromatography for the determination of five organophosphorus pesticide residues in fruits.

    PubMed

    Seebunrueng, Ketsarin; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

    2015-01-01

    A simple and rapid microextraction method, vortex-assisted low density solvent liquid-liquid microextraction and salt-induced demulsification (VLLME-SID) coupled to high performance liquid chromatography (HPLC) was developed for the determination of organophosphorus pesticide (OPP) residues in fruits. The studied OPPs were azinphos-methyl, parathion-methyl, fenitrothion, diazinon and chlorpyrifos. For VLLME-SID, a mixture of low density solvents (1-dodecanol and hexane) was used as the extraction solvent under vortex agitation for enhancing dispersion. After complete dispersion, the emulsion was formed and the OPPs were extracted into extraction solvent droplets. Then, the emulsion was quickly broken up into two clear phases after the addition of AlCl3 as a demulsifier. Centrifugation was not required in this procedure. Under the optimal conditions, high enrichment factors (180-282), low limit of detections (LODs) (0.05-1 ng mL(-1)) and good precision (RSD≤7% for retention time and peak area) were obtained. The proposed method was successfully applied to the analysis of OPP residues in fruit samples (watermelon, grape, and cantaloupe). The LODs for samples were in the range 0.0006-0.0015 mg kg(-1) which are below the established EU-MRLs (0.01-0.3 mg kg(-1)). Good recoveries were also obtained (80-104%). PMID:25476376

  2. Biodegradation and Utilization of Organophosphorus Pesticide Malathion by Cyanobacteria

    PubMed Central

    Ibrahim, Wael M.; Karam, Mohamed A.; El-Shahat, Reda M.; Adway, Asmaa A.

    2014-01-01

    Three strains of filamentous Cyanobacteria were used to study their growth and utilization of organophosphorus pesticide malathion. A sharp decrease in the growth of the algal strains was observed by increasing the concentration of malathion. Amongst them Nostoc muscorum tolerated different concentrations and was recorded as the highest efficient strain for biodegradation (91%) of this compound. Moreover, carbohydrate and protein content of their cells overtopped the other strains especially at higher concentrations. The algal strains were further subjected to grow under P-limitation in absence and presence of malathion. Although, the algal growth under P-limitation recorded a very poor level, a massive enhanced growth and phosphorous content of cells were obtained when the P-limited medium was amended with malathion. This study clarified that N. muscorum with its capability to utilize malathion as a sole phosphorous source is considered as an inexpensive and efficient biotechnology for remediation of organophosphorus pesticide from contaminated wastewater. PMID:24864237

  3. Household organophosphorus pesticide use and Parkinson’s disease

    PubMed Central

    Narayan, Shilpa; Liew, Zeyan; Paul, Kimberly; Lee, Pei-Chen; Sinsheimer, Janet S; Bronstein, Jeff M; Ritz, Beate

    2013-01-01

    Background Household pesticide use is widespread in the USA. Since the 1970s, organophosphorus chemicals (OPs) have been common active ingredients in these products. Parkinson’s disease (PD) has been linked to pesticide exposures but little is known about the contributions of chronic exposures to household pesticides. Here we investigate whether long-term use of household pesticides, especially those containing OPs, increases the odds of PD. Methods In a population-based case-control study, we assessed frequency of household pesticide use for 357 cases and 807 controls, relying on the California Department of Pesticide Regulation product label database to identify ingredients in reported household pesticide products and the Pesticide Action Network pesticide database of chemical ingredients. Using logistic regression we estimated the effects of household pesticide use. Results Frequent use of any household pesticide increased the odds of PD by 47% [odds ratio (OR) = 1.47, (95% confidence interval (CI): 1.13, 1.92)]; frequent use of products containing OPs increased the odds of PD more strongly by 71% [OR = 1.71, (95% CI: 1.21, 2.41)] and frequent organothiophosphate use almost doubled the odds of PD. Sensitivity analyses showed that estimated effects were independent of other pesticide exposures (ambient and occupational) and the largest odds ratios were estimated for frequent OP users who were carriers of the 192QQ paraoxonase genetic variant related to slower detoxification of OPs. Conclusions We provide evidence that household use of OP pesticides is associated with an increased risk of developing PD. PMID:24057998

  4. Phototransformation of selected organophosphorus pesticides in dilute aqueous solutions.

    PubMed

    Zamy, Cécile; Mazellier, Patrick; Legube, Bernard

    2004-05-01

    The photochemical transformation of four selected organophosphorus pesticides (OPs) has been studied in water. Because of their extensive use, disulfoton, isofenfos, isazofos and profenofos were chosen for this study. A solid phase extraction method has been developed to allow low-concentration experiments. Photolysis experiments have been performed both in purified water and in Capot river water (natural water from Martinique) using either monochromatic light at 253.7 nm (purified water) or polychromatic light greater than 285 nm (purified and Capot river waters). Kinetic investigations coupled with analytical studies (identification of degradation products) were performed for the four pesticides. Upon monochromatic irradiation, quantum yields of OP photolysis have been evaluated and in polychromatic irradiation experiments, apparent first-order kinetic constants have been determined. The reactivity is similar in purified and natural water, but differences are observed for each pesticide according to the role that natural organic matter (NOM) plays: filter effect of the light or photosensitizer. For each organophosphorus pesticide, experiments have been performed to identify the photodegradation products. Some photoproduct structures will be proposed according to mass spectral informations. PMID:15142791

  5. Chloramination of organophosphorus pesticides found in drinking water sources.

    PubMed

    Duirk, Stephen E; Desetto, Lisa M; Davis, Gary M; Lindell, Cristal; Cornelison, Christopher T

    2010-02-01

    The degradation of commonly detected organophosphorus (OP) pesticides, in drinking water sources, was investigated under simulated chloramination conditions. Due to monochloramine autodecomposition, it is difficult to observe the direct reaction of monochloramine with each OP pesticide. Therefore, a model was developed to examine the reaction of monochloramine (NH(2)Cl) and dichloramine (NHCl(2)) with chlorpyrifos (CP), diazinon (DZ), and malathion (MA). Monochloramine was found not to be very reactive with each OP pesticides, (k)NH(2)Cl,OP = 11-21 M(-1)h(-1). While, dichloramine (NHCl(2)) was found to be 2 orders of magnitude more reactive with each of the OP pesticides than monochloramine, (k)NHCl(2),OP = 2000-2900 M(-1)h(-1), which is still three orders of magnitude less than the hypochlorous acid reaction rate coefficient with each OP pesticide. For each pesticide, the reactivity of the three chlorinated oxidants was then found to correlate with half-wave potentials (E(1/2)) of each oxidant. With reaction rate coefficients for the three chlorinated oxidations as well as neutral and alkaline hydrolysis rate coefficients for the pesticides, the model was used to determine the dominant reaction pathways as a function of pH. At pH 6.5, OP pesticide transformation was mostly due to the reaction of hypochlorous acid and dichloramine. Above pH 8, alkaline hydrolysis or the direct reaction with monochloramine was the primary degradation pathway responsible for the transformation of OP pesticides. This demonstrates the ability of models to be used as tools to elucidate degradation pathways and parameterize critical reaction parameters when used with select yet comprehensive data sets. PMID:19900689

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

    USGS Publications Warehouse

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

    1988-01-01

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

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

    PubMed

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

    2016-09-01

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

  8. Novel and rapid method for determination of organophosphorus pesticide residues in edible fungus using direct gas purge microsyringe extraction coupled on-line with gas chromatography-mass spectrometry.

    PubMed

    Nan, Jingxi; Wang, Juan; Piao, Xiangfan; Yang, Cui; Wu, Xue; Quinto, Maurizio; Li, Donghao

    2015-09-01

    In this work a new analytical method for a rapid and simultaneous determination of 28 organophosphorus pesticides (OPPs) residues in edible fungus using gas purge microsyringe extraction (GP-MSE), coupled with on-line gas chromatography-mass spectrometry (GP-MSE-GC-MS) has been developed and optimized. GP-MSE, a novel gas flow liquid-phase microextraction technique, has been then fruitfully used as innovative and one-step extraction procedure, allowing a direct injection into the gas chromatograph coupled with a mass spectrometry detector (GC-MS) system without any further cleaning step. Once optimized, the GP-MSE-GC-MS analysis procedure showed reproducibility values, resolutions, linear responses, detection and quantification limits that allowed to consider this method suitable for the analysis of the 28 OPPs in real samples. Furthermore, OPP recoveries and the relative standard deviations (RSDs) ranged from 85.26% to 100.21%, and from 1.6% to 6.9%, respectively. This procedure was then used for the analysis of real samples and the obtained results were compared with those of ultrasonic extraction-solid phase extraction. Among the 28 OPPs, 14 of them were found in Lentinus edodes and Enoki mushrooms fungus samples, with a total concentrations of 112.7 and 210.7 μg kg(-1), respectively. This work demonstrated then that GP-MSE-GC-MS provided a highly efficient, solvent-saving, accurate and sensitive quantitative analysis method for a rapid determination of OPPs in edible fungus. PMID:26003693

  9. [Multiresidue analysis of organophosphorus pesticides in vegetables and fruits using dual-column GC-FPD, -NPD].

    PubMed

    Ueno, E; Oshima, H; Saito, I; Matsumoto, H

    2001-12-01

    We investigated simultaneous and consecutive analytical methods for pesticide residues in large numbers of vegetable and fruit samples. Extraction of the sample with acetonitrile was followed by a salting-out step using a graduated cylinder. Co-extractives were removed by gel permeation chromatography (GPC) and the pesticide eluate was separated to 2 fractions. Firstly, the second fraction (85-125 mL) was passed through a silica-gel mini-column. After putting a Florisil mini-column before the silica-gel mini-column, the first fraction (55-85 mL) was passed through the tandem mini-columns, which were then eluted with 15 mL of 50% acetone/petroleum ether. The eluate was subjected to dual-column GC with dual FPD (P mode, column Rtx-OPPesticides) and NPD (column Rtx-200) detectors. Recoveries of 63 organophosphorus pesticides from fortified spinach, tomato, apple and strawberry, ranged from 71 to 126% with RSD values of 1-18%, except for the RSDs of omethoate, isoxathion, and pyraclofos (20% <). Detection limits of pesticides were 0.5-2 ng/g. Surveillance of pesticides in vegetables and fruits was carried out by using the present method. From 20 out of 30 samples, 15 pesticides (39 in total) were detected. The results indicated that the present method can be applied as an efficient and reliable tool for monitoring organophosphorus pesticide residues in vegetables and fruits. PMID:11875824

  10. Liquid-phase microextraction of organophosphorus pesticides using supramolecular solvent as a carrier for ferrofluid.

    PubMed

    Zohrabi, Parvin; Shamsipur, Mojtaba; Hashemi, Mahdi; Hashemi, Beshare

    2016-11-01

    A liquid-phase microextraction based on application of supramolecular solvent as a carrier for ferrofluid has been developed for the extraction and determination of three organophosphorus pesticides (OPPs). The ferrofluid was produced from combination of oleic acid coated magnetic particles and supramolecular solvent as the extractant solvent. Ferrofluid can be attracted by a magnet, and no centrifugation step was needed for phase separation. A response surface methodology (RSM) based on central composite design (CCD) was used for efficient optimization of the main variables in the extraction procedure. Under the optimum experimental conditions, the calibration curves found to be linear in the range of 0.5-400µgL(-1) with correlation coefficients ranging from 0.9967 to 0.9984. The intra-day and inter-day precision (RSD %) for 100 and 200µgL(-1) of each pesticides were in the range of 2.0-5.3% and 2.6-5.7%, respectively. The limit of detection (S/N=3), ranged from 0.1 to 0.35μgL(-1). The proposed method was successfully applied to the extraction and determination of organophosphorus pesticide residues in water and fruit juice samples. PMID:27591622

  11. Development of a heterologous enzyme-linked immunosorbent assay for organophosphorus pesticides with phage-borne peptide

    PubMed Central

    Hua, Xiude; Liu, Xiaofeng; Shi, Haiyan; Wang, Yanru; Kim, Hee Joo; Gee, Shirley J.; Wang, Minghua; Liu, Fengquan; Hammock, Bruce D.

    2015-01-01

    An enzyme-linked immunosorbent assay (ELISA) was developed to detect organophosphorus pesticides using a phage-borne peptide that was isolated from a cyclic 8-residue peptide phage library. The IC50 values of the phage ELISA ranged from 1.4 to 92.1 μg L−1 for eight organophosphorus pesticides (parathion-methyl, parathion, fenitrothion, cyanophos, EPN, paraoxon-methyl, paraoxon, fenitrooxon). The sensitivity was improved 120- and 2-fold compared to conventional homologous and heterologous ELISA, respectively. The selectivity of the phage ELISA was evaluated by measuring its cross-reactivity with 23 organophosphorus pesticides, among which eight were the main cross-reactants. The spike recoveries were between 66.1% and 101.6% for the detection of single pesticide residues of parathion-methyl, parathion and fenitrothion in Chinese cabbage, apple and greengrocery, and all of the coefficient of variation were less than or equal to 15.9%. Moreover, the phage ELISA results were validated by gas chromatography. The results indicate that isolating phage-borne peptides from phage display libraries is an alternative method for the development of a heterologous immunoassay and that the developed assay has a lower limit of detection than the chemically synthesized competitor assay. PMID:26290688

  12. SELECTED PESTICIDE RESIDUES AND METABOLITES IN URINE FROM A SURVEY OF THE U.S. GENERAL POPULATION

    EPA Science Inventory

    Residues of toxic chemicals in human tissues and fluids can be important indicators of exposure. Urine collected from a subsample of the second National Health and Nutrition Examination Survey was analyzed for organochlorine, organophosphorus, and chlorophenoxy pesticides or the...

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

    PubMed Central

    Chowdhury, Muhammed Alamgir Zaman; Jahan, Iffat; Karim, Nurul; Alam, Mohammad Khorshed; Rahman, Mohammad Abdur; Moniruzzaman, Mohammed; Gan, Siew Hua; Fakhruddin, Abu Naieum Muhammad

    2014-01-01

    In the present study, the residual pesticide levels were determined in eggplants (Solanum melongena) (n = 16), purchased from four different markets in Dhaka, Bangladesh. The carbamate and organophosphorus pesticide residual levels were determined by high performance liquid chromatography (HPLC), and the efficiency of gamma radiation on pesticide removal in three different types of vegetables was also studied. Many (50%) of the samples contained pesticides, and three samples had residual levels above the maximum residue levels determined by the World Health Organisation. Three carbamates (carbaryl, carbofuran, and pirimicarb) and six organophosphates (phenthoate, diazinon, parathion, dimethoate, phosphamidon, and pirimiphos-methyl) were detected in eggplant samples; the highest carbofuran level detected was 1.86 mg/kg, while phenthoate was detected at 0.311 mg/kg. Gamma radiation decreased pesticide levels proportionately with increasing radiation doses. Diazinon, chlorpyrifos, and phosphamidon were reduced by 40–48%, 35–43%, and 30–45%, respectively, when a radiation strength of 0.5 kGy was utilized. However, when the radiation dose was increased to 1.0 kGy, the levels of the pesticides were reduced to 85–90%, 80–91%, and 90–95%, respectively. In summary, our study revealed that pesticide residues are present at high amounts in vegetable samples and that gamma radiation at 1.0 kGy can remove 80–95% of some pesticides. PMID:24711991

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

    PubMed

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

    2016-08-01

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

  15. MOVEMENT AND DEPOSITION OF TWO ORGANOPHOSPHORUS PESTICIDES WITHIN A RESIDENCE AFTER INTERIOR AND EXTERIOR APPLICATIONS

    EPA Science Inventory

    Post-application temporal and spatial distributions of two organophosphorus pesticides, diazinon and chlorpyrifos, were monitored after homeowner applications for indoor and outdoor insect control. Samples were taken before and up to 12 days after treatments in the family room...

  16. UPTAKE AND PHYTOTRANSFORMATION OF ORGANOPHOSPHORUS PESTICIDES BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of organophosphorus (OP) pesticides (malathion, demeton-S-methyl, and crufomate) was investigated in vitro using the axenically aquatic cultivated plants parrot feather (Myriophyllum aquaticum), duckweed (Spirodela oligorrhiza L.), and elodea (E...

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

    PubMed

    Songa, Everlyne A; Okonkwo, Jonathan O

    2016-08-01

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2015-10-30

    Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation. PMID:25938642

  20. Multidimensional Profiling Platforms Reveal Metabolic Dysregulation caused by Organophosphorus Pesticides

    PubMed Central

    Medina-Cleghorn, Daniel; Heslin, Ann; Morris, Patrick J.; Mulvihill, Melinda M.; Nomura, Daniel K.

    2014-01-01

    We are environmentally exposed to countless synthetic chemicals on a daily basis with an increasing number of these chemical exposures linked to adverse health effects. However, our understanding of the (patho)physiological effects of these chemicals remains poorly understood, due in-part to a general lack of effort to systematically and comprehensively identify the direct interactions of environmental chemicals with biological macromolecules in mammalian systems in vivo. Here, we have used functional chemoproteomic and metabolomic platforms to broadly identify direct enzyme targets that are inhibited by widely used organophosphorus (OP) pesticides in vivo in mice and to determine metabolic alterations that are caused by these chemicals. We find that these pesticides directly inhibit over 20 serine hydrolases in vivo leading to widespread disruptions in lipid metabolism. Through identifying direct biological targets of OP pesticides, we show heretofore unrecognized modes of toxicity that may be associated with these agents and underscore the utility of utilizing multidimensional profiling approaches to obtain a more complete understanding of toxicities associated with environmental chemicals. PMID:24205821

  1. Organophosphorus pesticide exposure and neurobehavioral performance in Latino children living in an orchard community.

    PubMed

    Butler-Dawson, Jaime; Galvin, Kit; Thorne, Peter S; Rohlman, Diane S

    2016-03-01

    Children living in agricultural communities have a greater risk from pesticides due to para-occupational pathways. The goal of this study was to assess the impact of exposure to organophosphorus pesticides on the neurobehavioral performance of school-aged Latino children over time. Two exposure measures were used to estimate children's pesticide exposure: parent's occupation (agricultural or non-agricultural) and organophosphate residues in home carpet dust samples. During 2008-2011, 206 school-aged children completed a battery of neurobehavioral tests two times, approximately one year apart. The associations between both exposure measures and neurobehavioral performance were examined. Pesticide residues were detected in dust samples from both agricultural and non-agricultural homes, however, pesticides were detected more frequently and in higher concentrations in agricultural homes compared to non-agricultural homes. Although few differences were found between agricultural and non-agricultural children at both visits, deficits in learning from the first visit to the second visit, or less improvement, was found in agricultural children relative to non-agricultural children. These differences were significant for the Divided Attention and Purdue Pegboard tests. These findings are consistent with previous research showing deficits in motor function. A summary measure of organophosphate residues was not associated with neurobehavioral performance. Results from this study indicate that children in agricultural communities are at increased risk from pesticides as a result of a parent working in agricultural. Our findings suggest that organophosphate exposure may be associated with deficits in learning on neurobehavioral performance, particularly in tests of with motor function. In spite of regulatory phasing out of organophosphates in the U.S., we still see elevated levels and higher detection rates of several organophosphates in agricultural households than non

  2. Presence of organophosphorus pesticide oxygen analogs in air samples

    PubMed Central

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

    2012-01-01

    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 laboratory experiments were used to examine artificial formation of chlorpyrifos-oxon using OSHA Versatile Sampling (OVS) tubes as recommended by NIOSH method 5600. Additionally, we compared expected chlorpyrifos-oxon attributable to artificial transformation to observed chlorpyrifos-oxon in field samples from a 2008 Washington State Department of Health air monitoring study using non-parametric statistical methods. The amount of artificially transformed oxon was then modeled to determine the amount of oxon present in the environment. Toxicity equivalency factors (TEFs) for chlorpyrifos-oxon were used to calculate chlorpyrifos-equivalent air concentrations. The results demonstrate that the NIOSH-recommended sampling matrix (OVS tubes with XAD-2 resin) was found to artificially transform up to 30% of chlorpyrifos to chlorpyrifos-oxon, with higher percentages at lower concentrations (< 30 ng/m3) typical of ambient or residential levels. Overall, the 2008 study data had significantly greater oxon than expected by artificial transformation, but the exact amount of environmental oxon in air remains difficult to quantify with the current sampling method. Failure to conduct laboratory analysis for chlorpyrifos-oxon may result in underestimation of total pesticide concentration when using XAD-2 resin matrices for occupational or residential sampling. Alternative methods that can accurately measure both OP pesticides and their oxygen analogs should be used for air sampling, and a toxicity

  3. Presence of organophosphorus pesticide oxygen analogs in air samples

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

    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 laboratory experiments were used to examine artificial formation of chlorpyrifos-oxon using OSHA Versatile Sampling (OVS) tubes as recommended by NIOSH method 5600. Additionally, we compared expected chlorpyrifos-oxon attributable to artificial transformation to observed chlorpyrifos-oxon in field samples from a 2008 Washington State Department of Health air monitoring study using non-parametric statistical methods. The amount of artificially transformed oxon was then modeled to determine the amount of oxon present in the environment. Toxicity equivalency factors (TEFs) for chlorpyrifos-oxon were used to calculate chlorpyrifos-equivalent air concentrations. The results demonstrate that the NIOSH-recommended sampling matrix (OVS tubes with XAD-2 resin) was found to artificially transform up to 30% of chlorpyrifos to chlorpyrifos-oxon, with higher percentages at lower concentrations (<30 ng m-3) typical of ambient or residential levels. Overall, the 2008 study data had significantly greater oxon than expected by artificial transformation, but the exact amount of environmental oxon in air remains difficult to quantify with the current sampling method. Failure to conduct laboratory analysis for chlorpyrifos-oxon may result in underestimation of total pesticide concentration when using XAD-2 resin matrices for occupational or residential sampling. Alternative methods that can accurately measure both OP pesticides and their oxygen analogs should be used for air sampling, and a toxicity

  4. Determination of multi-residue insecticides of organochlorine, organophosphorus, and pyrethroids in wheat.

    PubMed

    Riazuddin; Khan, Muhammad Farhanullah; Iqbal, Sajid; Abbas, Muhammad

    2011-09-01

    The undesirable effects of green revolution include residues of extensively used pesticides in various food commodities. Several studies showed that pesticides could cause health problems. Keeping in view the problem of pesticide residues in various food commodities, the present study was conducted on domestic stored wheat as well as on imported wheat for the qualitative and quantitative analysis of organochlorine, organophosphorus and pyrethroids. Among the imported wheat, 22.5% samples were found contaminated by organophosphorus (chlorpyrifos 0.073-0.230 μg/g, malathion 0.0419-0.1003 μg/g) and pyrethroids (cypermethrin 0.1404-0.2005 μg/g, permethrin 0.0140-0.0480 μg/g) while in domestic wheat 6.7% samples were found contaminated by pyrethroids (deltamethrin 0.0650-1.2903 μg/g) only. Method used for extraction and analysis of insecticides was validated both by recovery studies and inter laboratory comparison proficiency test. The method recovery results show that the average recovery of the fortified wheat samples was in the range of 73.77%-100.17% with the RSD in the range of 2.21-9.27 whereas, the Z-scores of the inter laboratory comparison proficiency test's result was less than 2. PMID:21656043

  5. Recovery of cholinesterase activity in mallard ducklings administered organophosphorus pesticides

    USGS Publications Warehouse

    Fleming, W.J.; Bradbury, S.P.

    1981-01-01

    Oral doses of the organophosphorus pesticides acephate, dicrotophos, fensulfothion, fonofos, malathion, and parathion were administered to mallard ducklings (Anas platyrhynchos), and brain and plasma cholinesterase (ChE) activities were determined for up to 77 d after dosing. In vivo recovery of brain ChE activity to within 2 standard deviations of the mean activity of undosed birds occurred within 8 d, after being depressed an average of 25-58% at 24 h after dosing. In vivo recovery of plasma ChE appeared as fast as or faster than that of brain, but the pattern of recovery was more erratic and therefore statistical comparison with brain ChE recovery was not attempted. In vitro tests indicated that the potential for dephosphorylation to contribute to in vivo recovery of inhibited brain ChE differed among chemical treatments. Some ducklings died as a result of organophosphate dosing. In an experiment in which ducklings within each treatment group received the same dose (mg/kg), the brain ChE activity in birds that died was less than that in birds that survived. Brain ChE activities in ducklings that died were significantly different among pesticide treatments: fensulfothion > parathion> acephate > malathion (p < 0.05).

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

    PubMed

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

    2016-01-01

    Organophosphorus pesticides (OPs) represent a very important class of pesticides that are widely used in agriculture because of their relatively high-performance and moderate environmental persistence, hence the sensitive and specific detection of OPs is highly significant. Based on the inhibitory effect of acetylcholinesterase (AChE) induced by inhibitors, including OPs and carbamates, a colorimetric analysis was used for detection of OPs with computer image analysis of color density in CMYK (cyan, magenta, yellow and black) color space and non-linear modeling. The results showed that there was a gradually weakened trend of yellow intensity with the increase of the concentration of dichlorvos. The quantitative analysis of dichlorvos was achieved by Artificial Neural Network (ANN) modeling, and the results showed that the established model had a good predictive ability between training sets and predictive sets. Real cabbage samples containing dichlorvos were detected by colorimetry and gas chromatography (GC), respectively. The results showed that there was no significant difference between colorimetry and GC (P > 0.05). The experiments of accuracy, precision and repeatability revealed good performance for detection of OPs. AChE can also be inhibited by carbamates, and therefore this method has potential applications in real samples for OPs and carbamates because of high selectivity and sensitivity. PMID:27396650

  7. DEVELOPMENT OF RISK ASSESSMENT TECHNIQUES FOR SOIL BIOAVAILABILITY AND BIOACCUMULATION OF AN ORGANOPHOSPHORUS PESTICIDE

    EPA Science Inventory

    There is increased concern about the effects of organophosphorus (OP) pesticides on human and animal health. This class of chemicals has been shown to affect the immune function of macrophages and lymphocytes. Malathion, an OP compound, is one of the most widely used pesticides...

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

    Jensen, B H; Petersen, A; Christensen, T

    2009-07-01

    Organophosphorus and carbamate pesticides are acetylcholinesterase-inhibiting pesticides and as such have a common mode of action. We assessed the cumulative acute exposure of the population of Denmark to 25 organophosphorus and carbamate pesticide residues from the consumption of fruit, vegetables and cereals. The probabilistic approach was used in the assessments. Residue data obtained from the Danish monitoring programme carried out in the period 2004-2007, which included 6704 samples of fruit, vegetables and cereals, were used in the calculations. Food consumption data were obtained from the nationwide dietary survey conducted in 2000-2002. Contributions from 43 commodities were included in the calculations. We used the relative potency factor (RPF) approach to normalize the toxicity of the various organophosphorus and carbamate pesticides to the two index compounds chlorpyriphos and methamidophos. RPF values derived from the literature were used in the calculations. We calculated the cumulative acute exposure to 1.8% and 0.8% of the acute reference dose (ARfD) of 100 microg kg(-1) body weight (bw) day(-1) of chlorpyrifos as an index compound at the 99.9th percentile (P99.5) for children and adults, respectively. When we used methamidophos as the index compound, the cumulative acute intakes were calculated to 31.3% and 13.8% of the ARfD of 3 microg kg(-1) bw day(-1) at P99.9 for children and adults, respectively. With both index compounds, the greatest contributor to the cumulative acute exposure was apple. The results show that there is no cumulative acute risk for Danish consumers to acetylcholinesterase-inhibiting pesticides. PMID:19680979

  10. Preparation of Electrochemical Biosensor for Detection of Organophosphorus Pesticides

    PubMed Central

    Gothwal, Ashish; Beniwal, Puneet; Dhull, Vikas

    2014-01-01

    Polyvinyl chloride (PVC) can be used to develop reaction beaker which acts as electrochemical cell for the measurement of OP pesticides. Being chemically inert, corrosion resistant, and easy in molding to various shapes and size, PVC can be used for the immobilization of enzyme. Organophosphorus hydrolase was immobilized covalently onto the chemically activated inner surface of PVC beaker by using glutaraldehyde as a coupling agent. The carbon nanotubes paste working electrode was constructed for amperometric measurement at a potential of +0.8 V. The biosensor showed optimum response at pH 8.0 with incubation temperature of 40°C. Km and Imax for substrate (methyl parathion) were 322.58 µM and 1.1 µA, respectively. Evaluation study showed a correlation of 0.985, which was in agreement with the standard method. The OPH biosensor lost 50% of its initial activity after its regular use for 25 times over a period of 50 days when stored in 0.1 M sodium phosphate buffer, pH 8.0 at 4°C. No interference was observed by interfering species. PMID:25667593

  11. Development of apple certified reference material for quantification of organophosphorus and pyrethroid pesticides.

    PubMed

    Otake, Takamitsu; Yarita, Takashi; Aoyagi, Yoshie; Kuroda, Youko; Numata, Masahiko; Iwata, Hitoshi; Watai, Masatoshi; Mitsuda, Hitoshi; Fujikawa, Takashi; Ota, Hidekazu

    2013-06-01

    An apple certified reference material for the analysis of pesticide residues was issued by the National Metrology Institute of Japan. Organophosphorus and pyrethroid pesticides were sprayed on apples, and these were used as raw materials of certified reference material. The harvested apples were cut into small pieces, freeze-dried, pulverized, sieved, placed into 200 brown glass bottles (3g each), and sterilized by γ-irradiation. Stability and homogeneity assessment was performed, and the relative uncertainties due to instability (for an expiry date of 32 months) and inhomogeneity were 10.3-25.0% and 4.0-6.8%, respectively. The characterization was carried out using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides were obtained by isotope dilution mass spectrometry. Certified values were 2.28 ± 0.82 mg/kg for diazinon, 3.14 ± 0.79 mg/kg for fenitrothion, 1.55 ± 0.81 mg/kg for cypermethrin, and 2.81 ± 0.70 mg/kg for permethrin. PMID:23411239

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

    PubMed

    Qiu, Junlang; Chen, Guosheng; Zhou, Hong; Xu, Jianqiao; Wang, Fuxin; Zhu, Fang; Ouyang, Gangfeng

    2016-04-15

    In vivo solid-phase microextraction (SPME) sampling method coupled with gas chromatography-mass spectrometry (GC-MS) analysis was employed to trace the uptake and elimination of organophosphorus pesticides (OPPs) in two kinds of edible plants, cabbage (Brassica parachinensis) and aloe (Barbadensis). The metabolism of fenthion in aloe was also investigated by the liquid chromatography tandem mass spectrometry analysis (LC-MS/MS) to understand the fate of OPPs in living plants better. Transpiration stream concentration factor (TSCF) and depuration rate constants of the OPPs in living plants were obtained therein. The health risk of the OPPs treated aloe was estimated by the maximum residue limit (MRL) approach, and it revealed that the OPPs were rather safe for their fast degradable property. However, peak concentration of fenthion-sulfoxide was found to exceed the MRL and was higher than that of the parent fenthion, which indicated the potential risk of pesticide metabolites. This study highlighted the application of in vivo SPME for contaminant tracing in different living edible plants. The in vivo tracing method is very convenient and can provide more data to evaluate the risk of different pesticides, which are very important for the safety of agriculture production. PMID:26878720

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

    EPA Science Inventory

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

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

    PubMed

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

    2015-03-01

    Intoxication by organophosphorus compounds, especially by pesticides, poses a considerable risk to the affected individual. Countermeasures involve both medical intervention by means of antidotes as well as external decontamination to reduce the risk of dermal absorption. One of the few decontamination options available is Reactive Skin Decontamination Lotion (RSDL), which was originally developed for military use. Here, we present a (31)P NMR spectroscopy based methodology to evaluate the detoxification efficacy of RSDL with respect to a series of organophosphorus pesticides and nerve agents. Kinetic analysis of the obtained NMR data provided degradation half-lives proving that RSDL is also reasonably effective against organophosphorus pesticides. Unexpected observations of different RSDL degradation patterns are presented in view of its reported oximate-catalyzed mechanism of action. PMID:25597861

  15. Multiresidue determination of organophosphorus pesticides in solid waste environmental samples by gas chromatography.

    PubMed

    Wu, Shijian; Zhang, Huanyan; Chen, Beibei; Liu, Ming; Shen, Yanjun; Sha, Qichao; Zhi, Yuee; Zhou, Pei

    2014-01-01

    The method for the determination of 12 organophosphorus pesticides in solid waste was established. The organophosphorus pesticides were analyzed by Soxhlet extraction or accelerated solvent extraction (ASE)-SPE cartridge-flame photometric detector (FPD), and leaching solution by rotary oscillation-positive pressure filtration-liquid-liquid extraction-SPE cartridge-FPD. The differences of extraction efficiencies between Soxhlet and ASE were compared. Solvent of Soxhlet extraction, purification and recovery of organophosphorus pesticides in leaching conditions were also studied. The recoveries were 54.2-119.8%, and the average recovery was 87.7%. The RSD was 1.89-9.10% (n = 6), the average RSD was 6.88%, and the detection limit was 0.27-0.69 μg/kg. PMID:25903001

  16. Development of an indirect enzyme-linked immunosorbent assay for the organophosphorus pesticide paraoxon-methyl.

    PubMed

    Li, Zhuo-Kun; Zhu, Ying-Yue; Yin, Xiang-Gang; Peng, Chi-Fang; Chen, Wei; Liu, Li-Qiang; Yin, Li-Mei; Xu, Chuan-Lai

    2009-01-01

    In the present study, the synthesis of hapten for the organophosphorus (OP) pesticide paraoxon-methyl was developed, with a spacer arm (aminocarboxylic acid) attached at the aromatic ring. It was conjugated to bovine serum albumin (BSA) for use as an immunogen and to ovalbumin (OVA) for coating antigen for ELISA testing. Rabbits were immunized with the immunogen and two polyclonal antisera were produced and screened against the coating antigen using competitive indirect enzyme-linked immunosorbent assay (ELISA). For application to textile samples, the influence of several factors such as organic solvent, ionic strength, and pH on the ELISA results were studied. Under optimized conditions, the quantitative working range was 0.012-1.158 microg/mL with a limit of detection (LOD) of 0.005 microg/mL and the IC(50) was 0.115 microg/mL.There was negligible cross reactivity (CR) with other OP pesticides. The recoveries obtained by standard paraoxon-methyl addition to the different textile samples such as cotton, wool and muslin delaine were all from 86.0% to 108.0%. Therefore, the optimized ELISA may become a new convenient and economical analytical tool for monitoring paraoxon-methyl residues in textile samples. PMID:19811409

  17. Monoclonal antibody-based broad-specificity immunoassay for monitoring organophosphorus pesticides in environmental water samples

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The extensive use of organophosphorus pesticides (OPs) in agriculture and domestic settings can result in widespread water contamination. The development of easy-to-use and rapid-screening immunoassay methods in a class-selective manner is a topic of considerable environmental interest. In this wo...

  18. EFFECTS OF TEMPERATURE AND SOLVENT COMPOSITION ON THE CHIRALCEL OJ SEPARATION OF CHIRAL ORGANOPHOSPHORUS PESTICIDES

    EPA Science Inventory

    The separation of the enantiomers of twelve organophosphorus pesticides (OPs) was investigated on the CHIRALCEL?OJ column to determine whether the mobile phase composition, flow rate and column temperature could be optimized to yield at least partial separation of the enantiomers...

  19. Pesticide residues in vegetable samples from the Andaman Islands, India.

    PubMed

    Swarnam, T P; Velmurugan, A

    2013-07-01

    Vegetable samples of brinjal, okra, green chilli, crucifers, and cucurbits collected from farmers' field were tested for the presence of organochlorine (OC), organophosphorus (OP), and synthetic pyrethroid (SP) compounds using a gas chromatograph equipped with electron capture and flame thermionic detectors. Of the samples tested, 34.0% were found to have pesticide residues. Among the OC compounds, α-endosulfan, β-endosulfan, and endosulfan sulfate were detected in 14.5% of the samples with residues. These were taken from crucifer, okra, green chilli, and cucurbit samples. SP compound residues, such as α-cypermethrin, fenvalerate I, fluvalinate I, deltamethrin, and λ-cyhalothrin were detected in 32% of the samples with residues. OP compound residues such as chlorpyrifos, profenofos, monocrotophos, triazophos, ethion, dimethoate, and acephate were found in 54% of the samples with residues, which were taken from all vegetable samples. Of the positive samples, 15.3% were found to contain residues exceeding the prescribed maximum residue limit. The average pesticide residue content across all the vegetable samples was 0.108 ppm, with values ranging from 0.008 to 2.099 ppm. Multiple residues of more than one compound were detected in 34.1% of samples containing residues. PMID:23208759

  20. Three-dimensional graphene aerogel-supported iron oxide nanoparticles as an efficient adsorbent for magnetic solid phase extraction of organophosphorus pesticide residues in fruit juices followed by gas chromatographic determination.

    PubMed

    Mahpishanian, Shokouh; Sereshti, Hassan

    2016-04-22

    In this research, a magnetic three dimensional-graphene nanocomposite (3D-G-Fe3O4) was prepared, characterized and used as an effective nanoadsorbent in magnetic solid-phase extraction (MSPE) of eight organophosphorus pesticides (OPPs) from juice samples prior to gas chromatography-nitrogen phosphorous detection (GC-NPD). The properties and morphology of 3D-G-Fe3O4 were characterized by scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). The main experimental parameters affecting extraction recoveries including extraction time, amount of adsorbent, pH of sample solution, salt concentration and desorption conditions were carefully studied and optimized. The results showed wide linear concentration ranges with determination coefficients between 0.9973 and 0.9999. The limits of detection (S/N=3) of the method and limits of quantification (S/N=10) were from 1.2 to 5.1 ng L(-1) and 3.4-17.0 ng L(-1), respectively. The intra-day and inter-day RSDs were 2.6-5.1% and 3.5-6.9%, respectively. The method was successfully applied to the analysis of OPPs in fruit juices (apple, orange, grape, sour-cherry and apricot) with recoveries in range of 86.6-107.5%. The GC-NPD results were confirmed by gas chromatography-mass spectrometry (GC-MS). The results demonstrated that with combination of highly interconnected 3D network structure and magnetism property of adsorbent, 3D-G-Fe3O4 aerogel exhibited exceptional extraction ability towards the OPPs. PMID:27018186

  1. Organochlorine and organophosphorus residues in the fat of domestic farm animal species, Ontario, Canada 1986-1988.

    PubMed

    Frank, R; Braun, H E; Stonefield, K I; Rasper, J; Luyken, H

    1990-01-01

    During the period 1986-1988 a total of 602 samples of animal products were analysed for organochlorine and organophosphorus pesticides and industrial organic pollutants. Samples of abdominal fat were collected from avian, bovine, caprine, lupine, ovine and porcine species together with hen eggs. The following six compounds were identified in animal tissues: DDE, dieldrin, lindane, PCB, pentachlorophenol and tetrachlorophenol. Pentachlorophenol was the most frequently found contaminant, being identified in 35% of samples, and DDE was the second in 21%. All other contaminants were present in less than 10% of samples. The residues of all six compounds detected were added to give a combined residue. Forty-three per cent of samples had non-detectable residues. A further 31% had combined residues adding to less than 0.01 mg/kg. The highest combined residues ranged between 0.1 and 1.0 mg/kg and were present in 2.8% of samples. One egg sample had a residue of 0.16 mg/kg that exceeded the 0.1 mg/kg maximum residue limit for pentachlorophenol. Residues of chlordane and its metabolites, heptachlor and its epoxide, endosulphan and its sulphate metabolite, dicofol, HCB and mirex were below their detection limits in all samples and no residues of the organophosphorus insecticide listed as applied to livestock were found in meat, fat or egg tissues. PMID:2253807

  2. Application of brain cholinesterase reactivation to differentiate between organophosphorus and carbamate pesticide exposure in wild birds

    USGS Publications Warehouse

    Smith, W.R.; Thomas, N.J.; Hulse, C.

    1995-01-01

    Brain cholinesterase activity was measured to evaluate pesticide exposure in wild birds. Thermal reactivation of brain cholinesterase was used to differentiate between carbamate and organophosphorus pesticide exposure. Brain cholinesterase activity was compared with gas chromatography and mass spectrometry of stomach contents. Pesticides were identified and confirmed in 86 of 102 incidents of mortality from 29 states within the USA from 1986 through 1991. Thermal reactivation of cholinesterase activity was used to correctly predict carbamates in 22 incidents and organophosphates in 59 incidents. Agreement (P < 0.001) between predictions based on cholinesterase activities and GC/MS results was significant.

  3. ORGANOPHOSPHORUS HYDROLASE-BASED ASSAY FOR ORGANOPHOSPHATE PESTICIDES

    EPA Science Inventory

    We report a rapid and versatile Organophosphorus hydrolase (OPH)-based method for measurement of organophosphates. This assay is based on a substrate-dependent change in pH at the local vicinity of the enzyme. The pH change is monitored using fluorescein isothiocyanate (FITC), ...

  4. [Ecological risk assessment of organophosphorus pesticides in aquatic ecosystems of Pearl River Estuary].

    PubMed

    Guo, Qiang; Tian, Hui; Mao, Xiao-Xuan; Huang, Tao; Gao, Hong; Ma, Jian-Min; Wu, Jun-Nian

    2014-03-01

    The risk quotient method and a probabilistic risk assessment method were applied for assessing aquatic ecological risk of nine organophosphorus pesticides, including thimet, dichlorovos, disulfoton, dimethoate, dimethyl parathion, chlorpyrifos, ethoprophos, sumithion and malathion on eight aquatic organisms in the Pearl River Estuary. Results using the risk quotient method revealed that the risk level of opossum shrimp was the highest among eight aquatic organisms of the Pearl River Estuary. The risk of water flea and midge was in medium level, followed by the rest six aquatic organisms, including diatom, oyster, carp, catfish and eel, which were in the low risk by the examined organophosphorus pesticides. It was found that thimet made the largest contribution to total aquatic ecological risk among nine organophosphorus pesticides to every organism. The results from probabilistic risk assessment showed that the total ecological risk in high water period was higher than that in low water period determined by the HC5 under the 95% confidence level. The largest contribution of thimet to total aquatic ecological risk subject to the HC5 in 50% confidence level was regarded as the toxic reference value. The probabilistic risk of a single contaminant showed that thimet and disulfoton were harmful to exceeded 10% organisms in the estuarine. The probabilistic risk of nine pesticides mixture in high water period was also higher than that in low water period, and both risks were greater than 5% which exceeded safety threshold for 95% organisms in the Pearl River Estuary. PMID:24881393

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

    PubMed

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

    2015-03-01

    A simple and efficient integrated microwave processing system (IMPS) was firstly assembled and validated for the extraction of organophosphorus pesticides in fresh vegetables. Two processes under microwave irradiation, dynamic microwave-assisted extraction (DMAE) and microwave-accelerated solvent elution (MASE), were integrated for simplifying the pretreatment of the sample. Extraction, separation, enrichment and elution were finished in a simple step. The organophosphorus pesticides were extracted from the fresh vegetables into hexane with DMAE, and then the extract was directly introduced into the enrichment column packed with active carbon fiber (ACF). Subsequently, the organophosphorus pesticides trapped on the ACF were eluted with ethyl acetate under microwave irradiation. No further filtration or cleanup was required before analysis of the eluate by gas chromatography-mass spectrometry. Some experimental parameters affecting extraction efficiency were investigated and optimized, such as microwave output power, kind and volume of extraction solvent, extraction time, amount of sorbent, elution microwave power, kind and volume of elution solvent, elution solvent flow rate. Under the optimized conditions, the recoveries were in the range of 71.5-105.2%, and the relative standard deviations were lower than 11.6%. The experiment results prove that the present method is a simple and effective sample preparation method for the determination of pesticides in solid samples. PMID:25618681

  6. Partitioning of organophosphorus pesticides into phosphatidylcholine small unilamellar vesicles studied by second-derivative spectrophotometry

    NASA Astrophysics Data System (ADS)

    Takegami, Shigehiko; Kitamura, Keisuke; Ohsugi, Mayuko; Ito, Aya; Kitade, Tatsuya

    2015-06-01

    In order to quantitatively examine the lipophilicity of the widely used organophosphorus pesticides (OPs) chlorfenvinphos (CFVP), chlorpyrifos-methyl (CPFM), diazinon (DZN), fenitrothion (FNT), fenthion (FT), isofenphos (IFP), profenofos (PFF) and pyraclofos (PCF), their partition coefficient (Kp) values between phosphatidylcholine (PC) small unilamellar vesicles (SUVs) and water (liposome-water system) were determined by second-derivative spectrophotometry. The second-derivative spectra of these OPs in the presence of PC SUV showed a bathochromic shift according to the increase in PC concentration and distinct derivative isosbestic points, demonstrating the complete elimination of the residual background signal effects that were observed in the absorption spectra. The Kp values were calculated from the second-derivative intensity change induced by addition of PC SUV and obtained with a good precision of R.S.D. below 10%. The Kp values were in the order of CPFM > FT > PFF > PCF > IFP > CFVP > FNT ⩾ DZN and did not show a linear correlation relationship with the reported partition coefficients obtained using an n-octanol-water system (R2 = 0.530). Also, the results quantitatively clarified the effect of chemical-group substitution in OPs on their lipophilicity. Since the partition coefficient for the liposome-water system is more effective for modeling the quantitative structure-activity relationship than that for the n-octanol-water system, the obtained results are toxicologically important for estimating the accumulation of these OPs in human cell membranes.

  7. Organophosphorus pesticide-induced butyrylcholinesterase inhibition and potentiation of succinylcholine toxicity in mice.

    PubMed

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

    1999-01-01

    Succinylcholine is the most important rapid-acting depolarizing muscle relaxant during anesthesia. Its desirable short duration of action is controlled by butyrylcholinesterase, the detoxifying enzyme. There are two reported cases of prolonged paralysis from succinylcholine in patients poisoned with the organophosphorus insecticides parathion and chlorpyrifos. The present study examines the possibility that other organophosphorus and methylcarbamate pesticides might also prolong succinylcholine action by inhibiting butyrylcholinesterase using mice treated intraperitoneally as a model and relating inhibition of blood serum hydrolysis of butyrylthiocholine to potentiated toxicity (mouse mortality). The organophosphorus plant defoliant tribufos (4 h pretreatment, 160 mg/kg) and organophosphorus plant growth regulator ethephon (1 h pretreatment, 200 mg/kg) potentiate the toxicity of succinylcholine by seven- and fourfold, respectively. Some other pesticides or analogs are more potent sensitizers for succinylcholine toxicity with threshold levels of 0.5, 1.0, 1.7, 8, 10, and 67 mg/kg for phenyl saligenin cyclic phosphonate, profenofos, methamidophos, tribufos, chlorpyrifos, and ethephon, respectively. Enhanced mortality from succinylcholine is generally observed when serum butyrylcholinesterase is inhibited 55-94%. Mivacurium, a related nondepolarizing muscle relaxant also detoxified by butyrylcholinesterase, is likewise potentiated by at least threefold on 4 hour pretreatment with tribufos (25 mg/kg) or profenofos (10 mg/kg). PMID:9890196

  8. Pesticide residues in market foods in Shaanxi Province of China in 2010.

    PubMed

    Wang, Shumei; Wang, Zhilun; Zhang, Yibei; Wang, Jiang; Guo, Rong

    2013-06-01

    The aim of this study was to investigate the pesticide residues in market vegetables in Shaanxi Province of China. The concentrations of 33 pesticides were determined by gas chromatography (GC) in 285 samples. Ten organophosphorus pesticides (OPs) were found in concentrations ranging from 0.004 to 0.257 mg/kg. The mean levels of omethoate, phorate, chlorpyrifos, methidathion, ethoprophos in vegetables exceeded the maximum residue limits (MRLs) allowed by the Ministry of Health, of China. Other detectable OP pesticide residues levels were below their MRLs. Dicofol were detectable in green pepper and chives samples. Five pyrethroid pesticides (PYRs) were detectable in vegetable samples respectively. The results provide useful information on the current contamination status of a key agricultural area in China, and point to the need for urgent action to control the excessive use of some chemicals. PMID:23411338

  9. Organophosphorus and Organochlorine Pesticides Bioaccumulation by Eichhornia crassipes in Irrigation Canals in an Urban Agricultural System.

    PubMed

    Mercado-Borrayo, B M; Heydrich, Silke Cram; Pérez, Irma Rosas; Quiroz, Manuel Hernández; Hill, Claudia Ponce De León

    2015-01-01

    A natural wetland in Mexico City Metropolitan Area is one of the main suppliers of crops and flowers, and in consequence its canals hold a high concentration of organochlorine (OC) and organophosphorus (OP) pesticides. There is also an extensive population of water hyacinth (Eichhornia crassipes), which is considered a plague; but literature suggests water hyacinth may be used as a phytoremediator. This study demonstrates bioaccumulation difference for the OC in vivo suggesting their bioaccumulation is ruled by their log K(ow), while all the OP showed bioaccumulation regardless of their log K(ow). The higher bioaccumulation factors (BAF) of the accumulated OC pesticides cannot be explained by their log K(ow), suggesting that the OC pesticides may also be transported passively into the plant. Translocation ratios showed that water hyacinth is an accumulating plant with phytoremediation potential for all organophosphorus pesticides studied and some organochlorine pesticides. An equation for free water surface wetlands with floating macrophytes, commonly used for the construction of water-cleaning wetlands, showed removal of the pesticides by the wetland with room for improvement with appropriate management. PMID:25976884

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

    USGS Publications Warehouse

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

    1999-01-01

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

  11. Zirconium(IV) functionalized magnetic nanocomposites for extraction of organophosphorus pesticides from environmental water samples.

    PubMed

    Jiang, Li; Huang, Tengjun; Feng, Shun; Wang, Jide

    2016-07-22

    The widespread use of organophosphate pesticides (OPPs) in agriculture leads to residue accumulation in the environment which is dangerous to human health and disrupts the ecological balance. In this work, one nanocomposite immobilized zirconium (Zr, IV) was prepared and used as the affinity probes to quickly and selectively extract organophosphorus pesticides (OPPs) from water samples. The Fe3O4-ethylenediamine tetraacetic acid (EDTA)@Zr(IV) nanocomposites (NPs) were prepared by simply mixing Zr(IV) ions with Fe3O4-EDTA NPs synthesized by one-pot chemical co-precipitation method. The immobilized Zr(IV) ions were further utilized to capture OPPs based on their high affinity for the phosphate moiety in OPPs. Coupled with GC-MS, four OPPs were used as models to demonstrate the feasibility of this approach. Under the optimum conditions, the limits of detection for target OPPs were in the range of 0.10-10.30ngmL(-1) with relative standard deviations (RSDs) of 0.61-4.40% (n=3), respectively. The linear ranges were over three orders of magnitudes (correlation coefficients, R(2)>0.9995). The Fe3O4-EDTA@Zr(IV) NPs were successfully applied to extract OPPs samples with recoveries of 86.95-112.60% and RSDs of 1.20-10.42% (n=3) from two spiked real water. By the proposed method, the matrix interference could be effectively eliminated. We hope our finding can provide a promising alternative for the fast extraction of OPPs from complex real samples. PMID:27328881

  12. Pesticide residue level in tea ecosystems of Hill and Dooars regions of West Bengal, India.

    PubMed

    Bishnu, Avhik; Chakrabarti, Kalyan; Chakraborty, Ashis; Saha, Tapan

    2009-02-01

    In the present study we quantified the residues of organophosphorus (e.g. ethion and chlorpyrifos), organochlorine (e.g. heptachlor, dicofol, alpha-endosulfan, beta-endosulfan, endosulfan sulfate) and synthetic pyrethroid (e.g. cypermethrin and deltamethrin) pesticides in made tea, fresh tea leaves, soils and water bodies from selected tea gardens in the Dooars and Hill regions of West Bengal, India during April and November, 2006. The organophosphorus (OP) pesticide residues were detected in 100% substrate samples of made tea, fresh tea leaves and soil in the Dooars region. In the Hill region, 20% to 40% of the substrate samples contained residues of organophosphorus (OP) pesticides. The organochlorine (OC) pesticide residues were detected in 33% to 100% of the substrate samples, excluding the water bodies in the Dooars region and 0% to 40% in the Hill region. The estimated mean totals of studied pesticides were higher in fresh tea leaves than in made tea and soils. The synthetic pyrethroid (SP) pesticide residues could not be detected in the soils of both the regions and in the water bodies of the Dooars. Sixteen percent and 20% of the made tea samples exceeded the MRL level of chlorpyrifos in Dooars and Hill regions respectively. The residues of heptachlor exceeded the MRL in 33% (April) and 100% (November) in the Dooars and 40% (April) and 20% (November) in the Hill region. Based on the study it was revealed that the residues of banned items like heptachlor and chlorpyrifos in made tea may pose health hazards to the consumers. PMID:18286381

  13. OpdA, a bacterial organophosphorus hydrolase, prevents lethality in rats after poisoning with highly toxic organophosphorus pesticides

    PubMed Central

    Bird, Steven B.; Sutherland, Tara D.; Gresham, Chip; Oakeshott, John; Scott, Colin; Eddleston, Michael

    2008-01-01

    Organophosphorus (OP) pesticides poison more than 3,000,000 people every year in the developing world, mostly through intentional self-poisoning. Advances in medical therapy for OP poisoning have lagged, and current treatment is not highly effective with mortality of up to 40% in even the most advanced Western medical facilities. Administration of a broadly active bacterial OP hydrolase to patients in order to hydrolyze OPs in circulation might allow current therapies to be more effective. The objective of this work was to evaluate the efficacy of a new recombinant bacterial OP hydrolase (OpdA), cloned from Agrobacterium radiobacter, in rat models of two chemically distinct but highly toxic and rapidly acting OP pesticides: dichlorvos and parathion. Without OpdA treatment, median time to death in rats poisoned with 3 × LD50 of dichlorvos or parathion was 6 minutes and 25.5 minutes, respectively. Administration of a single dose of OpdA immediately after dichlorvos resulted in 100% survival at 24 hours, with no additional antidotal therapy. After parathion poisoning, OpdA alone caused only a delay to death. However, an additional two doses of OpdA resulted in 62.5% survival at 24 hours after parathion poisoning. In combination with pralidoxime therapy, a single dose of OpdA increased survival to 75% after parathion poisoning. Our results demonstrate that OpdA is able to improve survival after poisoning by two chemically distinct and highly toxic OP pesticides. PMID:18378376

  14. Pesticide Residues in Food: Your Daily Dose.

    ERIC Educational Resources Information Center

    Mott, Lawrie

    1985-01-01

    Extensive use of pesticides during food production has created concerns for certain involuntary risks. Examines these concerns: government role in control and monitoring pesticide use, proposals for reform, and how consumer awareness might be an effective pressure for finding remedies. A table listing produce and pesticide residues is included.…

  15. PESTICIDE RESIDUE RECOVERIES FROM SURFACE WIPES

    EPA Science Inventory

    Human exposure is a consequence of pesticide use indoors with a primary source resulting from residue deposition on household surfaces. Accurate measurements of surface residues is essential for estimating exposure from different routes. Various procedures have been developed ...

  16. Rapid detection of pesticide residue in apple based on Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Yongyu; Sun, Yunyun; Peng, Yankun; Dhakal, Sagar; Chao, Kuanglin; Liu, Qiaoqiao

    2012-05-01

    The potential of Raman spectroscopy in the analysis of low concentration organic contaminants on apples' surface was evidenced in this study. Chlorpyrifos, an organophosphorus pesticide, was used as a probe for this purpose. The characteristic peaks of fingerprints of pesticide on an aluminum substrate and apple fruit cuticle without pesticide residue were acquired first. Then a concentration range of chlorpyrifos (commercial products at 40%) solutions were made using deionised and distilled water. Single 100 μL droplets of the chlorpyrifos solutions were placed gently on apple fruit cuticles and left to dry before analysis. Through comparative analysis of the Raman spectra data collected, 341, 632 and 1237cm-1 were identified to detect the chlorpyrifos pesticide residue on apple surface. Based on the relationship between the Raman intensity of the most prominent peak at around 632cm-1 and the pesticide concentrations, the limit of detection of ordinary Raman spectrum for chlorpyrifos was estimated to be 48ppm.

  17. Determination of nine organophosphorus pesticides in cereals and kidney beans by capillary gas chromatography with flame photometric detection.

    PubMed

    Tang, Bo; Zhang, Jin-E; Zang, Li-Guo; Zhang, Yao-Zhong; Li, Xiang-Yang; Zhou, Li

    2005-08-01

    A method is developed for the determination of nine organophosphorus pesticide residues in cereals and kidney beans by capillary gas chromatography with flame-photometric detection. In this method, dichloromethane is used for clean-up after liquid-liquid extraction. It is shown that good separations are obtained using a fused-silica capillary column (DB-1701) by the optimized temperature program. In the spiked levels of 0.012-0.43 mg/kg, the recoveries are from 83.7% to 107%, with the relative standard deviation between 3.2% and 13% and limits of detection from 8.2 to 15 microg/kg. The method is rapid, sensitive, and practical. PMID:16176643

  18. Determination of Organophosphate Pesticides at a Carbon Nanotube/Organophosphorus Hydrolase Electrochemical Biosensor

    SciTech Connect

    Deo, R P.; Wang, Joseph; Block, I; Mulchandani, Ashok; Joshi, K; Trojanowicz, M; Scholz, F; Chen, Wilfred; Lin, Yuehe

    2005-02-08

    An amperometric biosensor for organophosphorus (OP) pesticides based on a carbon-nanotube (CNT) modified transducer and an organophosphorus hydrolase (OPH) biocatalyst is described. A bilayer approach with the OPH layer atop of the CNT film was used for preparing the CNT/OPH biosensor. The CNT layer leads to a greatly improved anodic detection of the enzymatically-generated p-nitrophenol product, including higher sensitivity and stability. The sensor performance was optimized with respect to the surface modification and operating conditions. Under the optimal conditions the biosensor was used to measure as low as 0.15 {micro}M paraoxon and 0.8 {micro}M methyl parathion with sensitivities of 25 and 6 nA/{micro}M, respectively.

  19. Simultaneous determination of three organophosphorus pesticides in different food commodities by gas chromatography with mass spectrometry.

    PubMed

    Vijaya Bhaskar Reddy, Ambavaram; Yusop, Zulkifli; Jaafar, Jafariah; Bin Aris, Azmi; Abdul Majid, Zaiton; Umar, Khalid; Talib, Juhaizah

    2016-06-01

    A sensitive and selective gas chromatography with mass spectrometry method was developed for the simultaneous determination of three organophosphorus pesticides, namely, chlorpyrifos, malathion, and diazinon in three different food commodities (milk, apples, and drinking water) employing solid-phase extraction for sample pretreatment. Pesticide extraction from different sample matrices was carried out on Chromabond C18 cartridges using 3.0 mL of methanol and 3.0 mL of a mixture of dichloromethane/acetonitrile (1:1 v/v) as the eluting solvent. Analysis was carried out by gas chromatography coupled with mass spectrometry using selected-ion monitoring mode. Good linear relationships were obtained in the range of 0.1-50 μg/L for chlorpyrifos, and 0.05-50 μg/L for both malathion and diazinon pesticides. Good repeatability and recoveries were obtained in the range of 78.54-86.73% for three pesticides under the optimized experimental conditions. The limit of detection ranged from 0.02 to 0.03 μg/L, and the limit of quantification ranged from 0.05 to 0.1 μg/L for all three pesticides. Finally, the developed method was successfully applied for the determination of three targeted pesticides in milk, apples, and drinking water samples each in triplicate. No pesticide was found in apple and milk samples, but chlorpyrifos was found in one drinking water sample below the quantification level. PMID:27095506

  20. Phototransformation of selected organophosphorus pesticides: roles of hydroxyl and carbonate radicals.

    PubMed

    Wu, Changlong; Linden, Karl G

    2010-06-01

    The phototransformation of two organophosphorus pesticides, parathion and chlorpyrifos, by hydroxyl radicals and carbonate radicals in aqueous solution were studied. Addition of hydrogen peroxide increased the UV degradation rates of both pesticides and data were simulated through kinetic modeling. The second-order rate constants of parathion and chlorpyrifos with hydroxyl radical were determined to be 9.7 +/- 0.5 x 10(9) and 4.9 +/- 0.1 x 10(9) M(-1) s(-1), respectively. The presence of bi/carbonate ions reduced the pesticide degradation rates via scavenging of hydroxyl radical but the formation of carbonate radical also contributed to the degradation of the pesticides with second-order reaction rate constants of 2.8 +/- 0.2 x 10(6) and 8.8 +/- 0.4 x 10(6) M(-1) s(-1) for parathion and chlorpyrifos, respectively. The dual roles of bicarbonate ion in UV/H2O2 treatment systems, i.e., scavenging of hydroxyl radicals and formation of carbonate radicals, were examined and discussed using a simulative kinetic model. The transformation of pesticides by carbonate radicals at environmentally relevant bi/carbonate concentrations was shown to be a significant contributor to the environmental fate of the pesticides and it reshaped the general phototransformation kinetics of both pesticides in UV/H2O2 systems. PMID:20537677

  1. N-acetylcysteine in Acute Organophosphorus Pesticide Poisoning: A Randomized, Clinical Trial.

    PubMed

    El-Ebiary, Ahmad A; Elsharkawy, Rasha E; Soliman, Nema A; Soliman, Mohammed A; Hashem, Ahmed A

    2016-08-01

    Organophosphorus poisoning is a major global health problem with hundreds of thousands of deaths each year. Research interest in N-acetylcysteine has grown among increasing evidence of the role of oxidative stress in organophosphorus poisoning. We aimed to assess the safety and efficacy of N-acetylcysteine as an adjuvant treatment in patients with acute organophosphorus poisoning. This was a randomized, controlled, parallel-group trial on 30 patients suffering from acute organophosphorus poisoning, who were admitted to the Poison Control Center of Tanta University Emergency Hospital, Tanta, Egypt, between April and September 2014. Interventions included oral N-acetylcysteine (600 mg three times daily for 3 days) as an added treatment to the conventional measures versus only the conventional treatment. Outcome measures included mortality, total dose of atropine administered, duration of hospitalization and the need for ICU admission and/or mechanical ventilation. A total of 46 patients were screened and 30 were randomized. No significant difference was found between both groups regarding demographic characteristics and the nature or severity of baseline clinical manifestations. No major adverse effects to N-acetylcysteine therapy were reported. Malondialdehyde significantly decreased and reduced glutathione significantly increased only in the NAC-treated patients. The patients on NAC therapy required less atropine doses than those who received only the conventional treatment; however, the length of hospital stay showed no significant difference between both groups. The study concluded that the use of N-acetylcysteine as an added treatment was apparently safe, and it reduced atropine requirements in patients with acute organophosphorus pesticide poisoning. PMID:26786042

  2. Determination of organophosphorus pesticides in wheat flour by supercritical fluid extraction and gas chromatography with nitrogen-phosphorus detection.

    PubMed

    Kim, D H; Heo, G S; Lee, D W

    1998-10-16

    Application of supercritical fluid extraction (SFE) for selective isolation of organophosphorus pesticides from a real-world matrix (wheat flour) has been described. The method uses extraction with supercritical carbon dioxide at 206.8 bar and 60 degrees C, followed by quantitation by gas chromatography with nitrogen-phosphorous detection without clean-up of the extracts. Comparison of SFE with a method currently employed for sample preparation (i.e., organic solvent extraction followed by liquid-liquid extraction and gel permeation chromatography clean-up) shows that the SFE technique simplifies the sample preparation step and speeds up the determination of organophosphorus pesticides in flour. Extraction times were 60 min for a 7 g sample size. This technique was able to determine organophosphorus pesticides (ethoprophos, diazinon, chlorpyrifos methyl, fenitrothion, parathion, phenthoate, EPN) in samples at the 10 ng/g level. PMID:9818429

  3. Organophosphorus pesticides detection using broad-specific single-stranded DNA based fluorescence polarization aptamer assay.

    PubMed

    Zhang, Cunzheng; Wang, Li; Tu, Zhui; Sun, Xing; He, Qinghua; Lei, Zhaojing; Xu, Chongxin; Liu, Yuan; Zhang, Xiao; Yang, Jingyi; Liu, Xianjin; Xu, Yang

    2014-05-15

    An approach is developed to detect the organophosphorus pesticides via competitive binding to a recombinant broad-specificity DNA aptamer with a molecular beacon (MB), the binding of the MB to the aptamer results in the activation of a fluorescent signal, which can be measured for pesticide quantification. Aptamers selected via the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) were structurally modified and truncated to narrow down the binding region of the target, which indicated that loops of the aptamer contributed different functions for different chemical recognition. Thereafter, a variant fused by two different minimum functional structures, was clarified with broad specificity and increased affinity. Further molecular docking and molecular dynamics simulations was conducted to understand the molecular interaction between DNA structure and chemicals. 3D modeling revealed a hot spot area formed by 3 binding sites, forces including hydrogen bonds and van der Waals interactions appear to play a significant role in enabling and stabilizing the binding of chemicals. Finally, an engineered aptamer based approach for the detection of organophosphorus pesticides was successfully applied in a test using a real sample, the limit of quantification (LOQ) for phorate, profenofos, isocarbophos, and omethoate reached 19.2, 13.4, 17.2, and 23.4 nM (0.005 mg L(-1)), respectively. PMID:24384262

  4. Confirmed organophosphorus and carbamate pesticide poisonings in South African wildlife (2009-2014).

    PubMed

    Botha, Christo J; Coetser, Heleen; Labuschagne, Leonie; Basson, Andre

    2015-01-01

    During a six-year period (from January 2009 to December 2014), specimens collected from 344 cases of suspected organophosphorus and carbamate pesticide poisonings in wildlife, including birds, were submitted to the Toxicology Laboratory (ARC-OVI) for analysis. A positive diagnosis was made in 135 (39%) of these cases. The majority of cases were from birds, which included Cape vultures (Gyps coprotheres) and African white-backed vultures (Gyps africanus) and bateleur eagles (Terathopius ecaudatus). In one incident 49 vultures were killed when a farmer intentionally laced carcasses with carbofuran in an attempt to control jackal predation. There were 22 incidents of poisoning in helmeted guineafowl (Numida meleagris). On nine different occasions blue cranes (Anthropoides paradiseus) were poisoned, in one incident 14 birds were reported to have been killed. Over the period of investigation, there were 20 cases of poisoning involving mammalian species, the majority being vervet monkeys (Chlorocebus pygerythrus). The carbamate pesticides were responsible for 57 incidents of poisoning. Aldicarb, carbofuran and methomyl were detected in 26, 18 and 12 cases respectively. The majority of organophosphorus pesticide poisonings were caused by diazinon (n = 19), monocrotophos (n = 13) and methamidophos (n = 10). PMID:26824339

  5. [Survey of pesticide residues in imported frozen vegetables and fruits (1989.4~2008.3)].

    PubMed

    Kobayashi, Maki; Ohtsuka, Kenji; Tamura, Yasuhiro; Tomizawa, Sanae; Kamijo, Kyoko; Iwakoshi, Keiko; Kageyama, Yuriko; Nagayama, Toshihiro; Takano, Ichiro

    2011-01-01

    A survey of pesticide residues in 595 imported frozen products on the Tokyo market from April 1989 to March 2008 was carried out. Forty three kinds of pesticides, including organophosphorus, organochlorine, carbamate, pyrethroid and others, were detected between levels of trace (below 0.01 ppm) and 4.6 ppm from 162 samples. Chlorpyrifos, cypermethrin and omethoate were frequently detected in green vegetables (komatsuna leaf and spinach), cypermethrin and methamidophos were detected in pods and seeds (green soybean and string pea), chlorpropham (CIPC) was detected in potato, and captan and carbaryl were detected in berries (blueberry, raspberry and strawberry). The hydrophilic pesticide methamidophos was detected in flesh of lychee. Residue levels of these pesticides were calculated as between less than 0.5% and 30% of their ADI values according to the daily intake of frozen products. Therefore, these frozen products should be safe when they were eaten in customary amounts. PMID:21515967

  6. Dietary exposure to organophosphorus pesticides for young children in Tokyo and neighboring area.

    PubMed

    Kawahara, Junko; Yoshinaga, Jun; Yanagisawa, Yukio

    2007-06-01

    Dietary ingestion is a significant pathway of human exposure to organophosphorus (OP) pesticides. This study aims to determine the occurrence of OP pesticide in the diet of young children in Japan and estimate their exposure. The study was conducted by analyzing duplicate diet samples collected from 33 children aged 3 to 6 years old in Tokyo and the nearby area in Japan. Seven OP pesticides that are mainly used for agriculture in Japan (fenitrothion, trichlorfon, dichlorvos, diazinon, chlorpyrifos, malathion, and EPN) were targeted for analysis. As a result of the study, fenitrothion was frequently found in the week's diet (21%) of children, followed by diazinon (14%), chlorpyrifos (11%), and malathion (4%); the daily intake of pesticides was also estimated to range from < 110 to 180 ng/day, < 70 to 800 ng/day, < 70 to 100 ng/day, and < or = 110 ng/day, respectively. Daily intake of diazinon per kg body weight was relatively higher than other target pesticides and the maximum value was 50 times below the acceptable daily intake set by Japan Ministry of Health and Labor Welfare. Occurrence of malathion in the diet of children in the present study was lower than that reported in 1980s, supposed due to the decreasing level of malathion in wheat and wheat products. Frequent detection of fenitrothion in diet is a significant trend observed in Japan, and is considered due to the high and widespread usage of the pesticide inside of the country. PMID:17412399

  7. Gestational Hypertension and Organophosphorus Pesticide Exposure: A Cross-Sectional Study

    PubMed Central

    Ledda, Caterina; Fiore, Maria; Santarelli, Lory; Bracci, Massimo; Mascali, Giuseppe; D'Agati, Maria Grazia; Busà, Alfredo; Ferrante, Margherita; Rapisarda, Venerando

    2015-01-01

    Hypertension is the most common medical problem encountered during pregnancy, complicating 2-3% of pregnancies. High blood pressure (BP) with diastolic BP ≥ 90 mm Hg and/or systolic BP ≥ 140 mm Hg arising after week 22 of pregnancy and resolving after delivery is defined as gestational hypertension (GHY). The aim of this cross-sectional study was to investigate whether occupational and/or environmental exposure to organophosphorus (OP) pesticide affects GHY. Women at approximately 22 weeks of gestation were recruited. OP pesticide exposure in the first trimester of pregnancy was classified into four categories: no exposure, indirect exposure, domestic exposure, and occupational exposure. Application of the exclusion criteria left 2203 participants (mean age 30.4 ± 11.6 years). Data analysis showed that in women with indirect OP pesticide exposure the incidence of GHY was slightly higher than that in the world population, whereas domestic exposure involved a 7% increase and occupational exposure a 12% increase. Analysis of the pesticides used by participants highlighted a possible role for malathion and diazinon (adjusted OR 1.09 and 1.14, resp.). Further investigation of exposed workers and the general population is clearly warranted given the broad diffusion of OP pesticides and their possible public health impact, maybe by including a wider range of health outcomes. PMID:26339602

  8. Proposed protocols for the determination of potential ocular effects of organophosphorus pesticides.

    PubMed

    Hamernik, K L

    1994-01-01

    The US Environmental Protection Agency now requires ocular toxicity testing to support the registration of organophosphorus pesticides. As a first step toward guideline development for the conduct of these studies, preliminary protocols for ocular toxicity testing in the non-rodent and rodent are being proposed by the Office of Pesticide Programs. Proposed protocol parameters include determination of animal health status, measurement of plasma, erythrocyte and retinal cholinesterase activities, ocular assessment by routine ophthalmological examination, slit lamp biomicroscopy, fundic observations, tonometry, electroretinography and determination of objective refractivity, pupillary response and tracking. Gross and detailed histopathological examinations of ocular system components would also be conducted. Associated questions and concerns with regard to ocular toxicity testing are presented. The Agency plans to hold a workshop in the near future to discuss issues related to protocol refinement and guideline development. PMID:8027508

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

    PubMed

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

    2013-09-01

    Inhibitory effects of five organophosphorus pesticides (diazinon, malathion, chlorpyrifos, azinphos-methyl and phorate) and their oxo-analogs on human myeloperoxidase (MPO) activity were investigated. While inspecting separately peroxidase and chlorination activity, it was observed that investigated OPs affect peroxidase activity, but not chlorination activity. Among investigated pesticides, malathion and malaoxon have showed the highest power to inhibit MPO peroxidase activity with IC50 values of the order of 3×10(-7) and 5×10(-9) M, respectively. It was proposed that inhibition trend is rendered by molecular structure which invokes steric hindrance for OPs interaction with MPO active center responsible for peroxidase activity. In addition, it was concluded that physiological function of MPO is not affected by any of the investigated OPs. PMID:25149236

  10. Prediction for the mixture toxicity of six organophosphorus pesticides to the luminescent bacterium Q67.

    PubMed

    Zhang, Ya-Hui; Liu, Shu-Shen; Song, Xiao-Qing; Ge, Hui-Lin

    2008-11-01

    Organophosphorus (OP) pesticides are ubiquitous in the surface water as mixtures. To examine the mixture toxicity in the multi-component space, the uniform design (UD) which can explore the concentration changes with few experimental efforts was employed to design the mixtures. On the other hand, the fixed concentration ratio ray was applied into six UD mixtures and two equivalent-effect concentration mixtures to build the whole concentration-response curves to overcome the demerit of the classical "point-to-point" method. The experimental toxicities of six pesticides and their mixtures to the luminescent bacterium Q67 were determined. The mixture toxicities were predicted by two models, concentration addition (CA) and independent action (IA). The results showed that all the mixture toxicities observed had no significant differences from the ones predicted by CA. However, the mixture toxicities were also well predicted by IA especially at the low-concentration section. PMID:18308393

  11. Leaf surfaces and the bioavailability of pesticide residues.

    PubMed

    Chowdhury, A B; Jepson, P C; Howse, P E; Ford, M G

    2001-05-01

    Laboratory bioassays were carried out to determine the toxicity to Folsomia candida Willem (Collembola: Isotomidae) of residues of a pyrethroid insecticide, deltamethrin, and an organophosphorus insecticide, dimethoate, on different leaf surfaces. The test leaves included a range of species and leaves of different ages. Dose-response relationships were estimated for F candida walking over the various treated leaf substrates. Probit analysis was used to estimate the means and standard deviations of the associated tolerance distributions expressed as gAIha-1. Parallelism tests were undertaken to compare the susceptibilities of F candida to the two compounds applied to the different leaf surfaces. On deltamethrin-treated leaf surfaces, the LD50 values for F candida varied from 6.36 to 77.14 gAIha-1. F candida was least susceptible to deltamethrin residues when applied to leaves of dwarf bean (Phaseolus vulgarus L) and the highest susceptibility was observed following application to leaves of seedlings of barley (Hordeum vulgare L). In contrast, the LD50 values observed for dimethoate treatments did not differ significantly between leaf types, ranging from 1.35 to 8.69 gAIha-1. The laboratory data on susceptibility of F candida on different leaf types for different pesticides can be used to investigate the role of leaf surface properties in modifying the toxicity of applied pesticides to exposed invertebrates. PMID:11374156

  12. Cannabinoid CB1 receptor as a target for chlorpyrifos oxon and other organophosphorus pesticides.

    PubMed

    Quistad, Gary B; Nomura, Daniel K; Sparks, Susan E; Segall, Yoffi; Casida, John E

    2002-09-01

    Binding of the endocannabinoid anandamide or of Delta(9)-tetrahydrocannabinol to the agonist site of the cannabinoid receptor (CB1) is commonly assayed with [3H]CP 55,940. Potent long-chain alkylfluorophosphonate inhibitors of agonist binding suggest an additional, important and closely-coupled nucleophilic site, possibly undergoing phosphorylation. We find that the CB1 receptor is also sensitive to inhibition in vitro and in vivo by several organophosphorus pesticides and analogs. Binding of [3H]CP 55,940 to mouse brain CB1 receptor in vitro is inhibited 50% by chlorpyrifos oxon at 14 nM, chlorpyrifos methyl oxon at 64 nM and paraoxon, diazoxon and dichlorvos at 1200-4200 nM. Some 15 other organophosphorus pesticides and analogs are less active in vitro. The plant defoliant tribufos inhibits CB1 in vivo, without cholinergic poisoning signs, by 50% at 50 mg/kg intraperitoneally with a recovery half-time of 3-4 days, indicating covalent derivatization. [3H-ethyl]Chlorpyrifos oxon may be suitable for radiolabeling and characterization of this proposed nucleophilic site. PMID:12243867

  13. Development of phage immuno-loop-mediated isothermal amplification assays for organophosphorus pesticides in agro-products.

    PubMed

    Hua, Xiude; Yin, Wei; Shi, Haiyan; Li, Ming; Wang, Yanru; Wang, Hong; Ye, Yonghao; Kim, Hee Joo; Gee, Shirley J; Wang, Minghua; Liu, Fengquan; Hammock, Bruce D

    2014-08-19

    Two immuno-loop-mediated isothermal amplification assays (iLAMP) were developed by using a phage-borne peptide that was isolated from a cyclic eight-peptide phage library. One assay was used to screen eight organophosphorus (OP) pesticides with limits of detection (LOD) between 2 and 128 ng mL(-1). The iLAMP consisted of the competitive immuno-reaction coupled to the LAMP reaction for detection. This method provides positive results in the visual color of violet, while a negative response results in a sky blue color; therefore, the iLAMP allows one to rapidly detect analytes in yes or no fashion. We validated the iLAMP by detecting parathion-methyl, parathion, and fenitrothion in Chinese cabbage, apple, and greengrocery, and the detection results were consistent with the enzyme-linked immunosorbent assay (ELISA). In conclusion, the iLAMP is a simple, rapid, sensitive, and economical method for detecting OP pesticide residues in agro-products with no instrumental requirement. PMID:25135320

  14. Determination of pesticide residues in cannabis smoke.

    PubMed

    Sullivan, Nicholas; Elzinga, Sytze; Raber, Jeffrey C

    2013-01-01

    The present study was conducted in order to quantify to what extent cannabis consumers may be exposed to pesticide and other chemical residues through inhaled mainstream cannabis smoke. Three different smoking devices were evaluated in order to provide a generalized data set representative of pesticide exposures possible for medical cannabis users. Three different pesticides, bifenthrin, diazinon, and permethrin, along with the plant growth regulator paclobutrazol, which are readily available to cultivators in commercial products, were investigated in the experiment. Smoke generated from the smoking devices was condensed in tandem chilled gas traps and analyzed with gas chromatography-mass spectrometry (GC-MS). Recoveries of residues were as high as 69.5% depending on the device used and the component investigated, suggesting that the potential of pesticide and chemical residue exposures to cannabis users is substantial and may pose a significant toxicological threat in the absence of adequate regulatory frameworks. PMID:23737769

  15. DEVELOPMENT OF AN IN VITRO ASSAY THAT MAY IDENTIFY WHICH ORGANOPHOSPHORUS PESTICIDES ARE MORE TOXIC TO THE YOUNG.

    EPA Science Inventory

    Some, but not all, organophosphorus pesticides are more acutely toxic to the young as compared to adults. We have developed an in vitro assay which measures the detoxification potential (via carboxylesterase and A-esterases) of tissues. Previous results using this in vitro assay ...

  16. Transformation of Organophosphorus Pesticides in the Presence of Aqueous Chlorine: Kinetics, Pathways, and Structure-Activity Relationships

    EPA Science Inventory

    The fate of organophosphorus (OP) pesticides in the presence of aqueous chlorine was investigated under simulated drinking water treatment conditions. Intrinsic rate coefficients were found for the reaction of hypochlorous acid (kHOCl,OP) and hypochlorite ion (kOCl,OP) for eight...

  17. DEVELOPMENT OF A RISK ASSESSMENT MODEL FOR THE EFFECTS OF ORGANOPHOSPHORUS PESTICIDES ON INFECTIOUS DISEASE SUSCEPTIBILITY AND THE IMMUNE SYSTEM

    EPA Science Inventory

    There is increased concern about the sublethal effects of organophosphorus (OP) pesticides on human and animal health. This class of chemicals has been shown to affect the immune function of macrophages and lymphocytes. Malathion, an OP compound, is one of the most widely used ...

  18. COMPARISON OF PLASMA CHOLINESTERASE DEPRESSION AMONG WORKERS OCCUPATIONALLY EXPOSED TO ORGANOPHOSPHORUS PESTICIDES AS REPORTED BY VARIOUS STUDIES

    EPA Science Inventory

    A number of studies have reported on the inhibitory effects of organophosphorus pesticides (OPs) on the enzyme cholinesterase (ChE) among agricultural workers. With the increasing use of OPs, surveys of blood ChE activity on exposed workers may help to identify workers at greates...

  19. [Determination of 21 organophosphorus pesticides in tea by gas chromatography-mass spectrometry coupled with hydroxylated multi-walled carbon nanotubes based on dispersive solid-phase extraction].

    PubMed

    Rong, Jiefeng; Wei, Hang; Li, Yijun; Huang, Huoshui; Xu, Meizhu

    2016-02-01

    A rapid determination method of 21 organophosphorus pesticides in tea was developed by QuEChERS method using modified multi-walled carbon nanotubes (MWCNTs-OH), primary-secondary amine (PSA) and MgSO4 coupled with gas chromatography-mass spectrometry. The pesticide residues in tea were extracted with a hexane-acetone (2:1, v/v) mixture, and cleaned up by dispersive solid-phase extraction using MWCNTs-OH and primary-secondary amine (PSA) as the sorbents. After centrifugation and filtration, the target compounds were analyzed by gas chromatography-mass spectrometry and quantified by the external standard method. Under the optimized conditions, good linearities were obtained in the range of 0. 01- 0. 50 mg/kg. The average recoveries were in the range of 81. 5% -109. 4% at three spiked levels, with relative standard deviations (RSDs, n = 5 ) of 2. 3% - 10. 6%. The limits of quantification were 0. 001-0. 040 mg/kg. This method is simple, fast, sensitive, cheap, and can meet the requirements of the rapid detection of organophosphorus pesticides in tea. PMID:27382726

  20. Multiresidue analysis of 102 organophosphorus pesticides in produce at parts-per-billion levels using a modified QuEChERS method and gas chromatography with pulsed flame photometric detection.

    PubMed

    Schenck, Frank; Wong, Jon; Lu, Chenseng; Li, Jing; Holcomb, Jim R; Mitchell, LaTonya M

    2009-01-01

    A multiresidue method for the analysis of organophosphorus pesticides in fresh produce at levels down to 1.0 microg/kg (ppb) has been developed using a modification of the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure. The procedure entails extraction of pesticides from the sample with acetonitrile, salting-out with magnesium sulfate (MgSO4) and sodium chloride, and cleanup of the resulting extracts with dispersive solid-phase extraction using primary-secondary amine, graphitized carbon black, and MgSO4. Fortification studies were performed for 102 organophosphorus pesticides at 1.0, 10, and 100 ppb in 4 different pesticide-free commodities (grape, orange, spinach, and tomato). Recoveries ranged from 63-125%, with >80% being achieved for most of the pesticides tested in each commodity. The procedure was applied to the analysis of 400 produce samples collected from a cohort of children that participated in the Children's Pesticide Exposure Study and the Longitudinal Dietary Pesticide Exposure Study in which selected 24 h duplicate food items were collected throughout a 12-month period. Residues of 15 of the 102 pesticides were detected at levels ranging from <1 to 526 ppb. PMID:19485217

  1. Application of a single-drop microextraction for the analysis of organophosphorus pesticides in juice.

    PubMed

    Zhao, Ercheng; Han, Lijun; Jiang, Shuren; Wang, Qiuxia; Zhou, Zhiqiang

    2006-05-12

    In this study, a new method for the determination of organophosphorus pesticides (OPPs) (ethoprophos, diazinon, parathion methyl, fenitrothion, malathion, isocarbophos and quinaphos) in orange juice was developed. Single-drop microextraction (SDME) parameters, such as organic solvent, drop volume, agitation rate, extraction time, and salt concentration were optimized through analysis of OPPs in fortified water. The orange juice was simply centrifuged and diluted with water, extracted by SDME and analyzed by gas chromatography (GC) equipped with a flame photometric detection (FPD). Fortification tests were conducted for concentrations between 10 and 500 microg/L; mean relative recoveries for each pesticide were all above 76.2% and below 108.0%. Limits of detection of the method for orange juice were below 5 microg/L for all target pesticides. The repeatability of the proposed method, expressed as relative standard deviation varied between 4.6 and 14.1% (n=5). The proposed method is acceptable in the analysis of OPPs pesticides in juice matrices. PMID:16569410

  2. Nanomaterials - Acetylcholinesterase Enzyme Matrices for Organophosphorus Pesticides Electrochemical Sensors: A Review

    PubMed Central

    Periasamy, Arun Prakash; Umasankar, Yogeswaran; Chen, Shen-Ming

    2009-01-01

    Acetylcholinesterase (AChE) is an important cholinesterase enzyme present in the synaptic clefts of living organisms. It maintains the levels of the neurotransmitter acetylcholine by catalyzing the hydrolysis reaction of acetylcholine to thiocholine. This catalytic activity of AChE is drastically inhibited by trace amounts of organophosphorus (OP) pesticides present in the environment. As a result, effective monitoring of OP pesticides in the environment is very desirable and has been done successfully in recent years with the use of nanomaterial-based AChE sensors. In such sensors, the enzyme AChE has been immobilized onto nanomaterials like multiwalled carbon nanotubes, gold nanoparticles, zirconia nanoparticles, cadmium sulphide nano particles or quantum dots. These nanomaterial matrices promote significant enhancements of OP pesticide determinations, with the thiocholine oxidation occurring at much lower oxidation potentials. Moreover, nanomaterial-based AChE sensors with rapid response, increased operational and long storage stability are extremely well suited for OP pesticide determination over a wide concentration range. In this review, the unique advantages of using nanomaterials as AChE immobilization matrices are discussed. Further, detection limits, sensitivities and correlation coefficients obtained using various electroanalytical techniques have also been compared with chromatographic techniques. PMID:22408512

  3. Determinants of Organophosphorus Pesticide Urinary Metabolite Levels in Young Children Living in an Agricultural Community

    PubMed Central

    Bradman, Asa; Castorina, Rosemary; Barr, Dana Boyd; Chevrier, Jonathan; Harnly, Martha E.; Eisen, Ellen A.; McKone, Thomas E.; Harley, Kim; Holland, Nina; Eskenazi, Brenda

    2011-01-01

    Organophosphorus (OP) pesticides are used in agriculture and several are registered for home use. As young children age they may experience different pesticide exposures due to varying diet, behavior, and other factors. We measured six OP dialkylphosphate (DAP) metabolites (three dimethyl alkylphosphates (DMAP) and three diethyl alkylphosphates (DEAP)) in urine samples collected from ∼400 children living in an agricultural community when they were 6, 12, and 24 months old. We examined bivariate associations between DAP metabolite levels and determinants such as age, diet, season, and parent occupation. To evaluate independent impacts, we then used generalized linear mixed multivariable models including interaction terms with age. The final models indicated that DMAP metabolite levels increased with age. DMAP levels were also positively associated with daily servings of produce at 6- and 24-months. Among the 6-month olds, DMAP metabolite levels were higher when samples were collected during the summer/spring versus the winter/fall months. Among the 12-month olds, DMAP and DEAP metabolites were higher when children lived ≤60 meters from an agricultural field. Among the 24-month-olds, DEAP metabolite levels were higher during the summer/spring months. Our findings suggest that there are multiple determinants of OP pesticide exposures, notably dietary intake and temporal and spatial proximity to agricultural use. The impact of these determinants varied by age and class of DAP metabolite. PMID:21695029

  4. Biological monitoring of organophosphorus pesticide exposure among children of agricultural workers in central Washington State.

    PubMed Central

    Loewenherz, C; Fenske, R A; Simcox, N J; Bellamy, G; Kalman, D

    1997-01-01

    Children up to 6 years of age who lived with pesticide applicators were monitored for increased risk of pesticide exposure: 48 pesticide applicator and 14 reference families were recruited from an agricultural region of Washington State in June 1995. A total of 160 spot urine samples were collected from 88 children, including repeated measures 3-7 days apart. Samples were assayed by gas chromatography flame photometric detector for dimethylphosphate metabolites. Dimethylthiophosphate (DMTP) was the dominant metabolite. DMTP levels were significantly higher in applicator children than in reference children (p = 0.015), with median concentrations of 0.021 and 0.005 microg/ml, respectively; maximum concentrations were 0.44 and 0.10 microg/ml, respectively. Percentages of detectable samples were 47% for applicator children and 27% for reference children. A marginally significant trend of increasing concentration was observed with decreasing age among applicator children (p = 0.060), and younger children within these families had significantly higher concentrations when compared to their older siblings (p = 0.040). Applicator children living less than 200 feet from an orchard were associated with higher frequency of detectable DMTP levels than nonproximal applicator children (p =0.036). These results indicate that applicator children experienced higher organophosphorus pesticide exposures than did reference children in the same community and that proximity to spraying is an important contributor to such exposures. Trends related to age suggest that child activity is an important variable for exposure. It is unlikely that any of the observed exposures posed a hazard of acute intoxication. This study points to the need for a more detailed understanding of pesticide exposure pathways for children of agricultural workers. Images Figure 1. Figure 2. Figure 3. PMID:9405329

  5. Anticonvulsant discovery through animal models of status epilepticus induced by organophosphorus nerve agents and pesticides.

    PubMed

    McCarren, Hilary S; McDonough, John H

    2016-06-01

    Organophosphorus pesticides (OPs) and nerve agents (NAs) are highly toxic chemicals that pose a significant threat to human health worldwide. These compounds induce status epilepticus (SE) by irreversibly blocking the ability of acetylcholinesterase to break down acetylcholine at neural synapses. Animal models of organophosphate-induced SE are a crucial resource for identifying new anticonvulsant therapies. Here, we describe the development of various animal models of SE induced by NA or OP exposure. Experiments in nonhuman primates, rats, mice, and guinea pigs have helped to identify novel therapeutic targets in the central nervous system, with particular success at modulating GABAergic and glutamatergic receptors. The anticonvulsants identified by NA- and OP-induced SE models are well poised for fast advancement into clinical development, and their potential utility in the broader field of epilepsy should make them all the more attractive for commercial pursuit. PMID:27258770

  6. Pharmacotherapy to protect the neuromuscular junction after acute organophosphorus pesticide poisoning.

    PubMed

    Bird, Steven B; Krajacic, Predrag; Sawamoto, Keigo; Bunya, Naofumi; Loro, Emanuele; Khurana, Tejvir S

    2016-06-01

    Organophosphorus (OP) pesticide poisoning is a leading cause of morbidity and mortality in the developing world, affecting an estimated three million people annually. Much of the morbidity is directly related to muscle weakness, which develops 1-4 days after poisoning. This muscle weakness, termed the intermediate syndrome (IMS), leads to respiratory, bulbar, and proximal limb weakness and frequently necessitates the use of mechanical ventilation. While not entirely understood, the IMS is most likely due to persistently elevated acetylcholine (ACh), which activates nicotinic ACh receptors at the neuromuscular junction (NMJ). Thus, the NMJ is potentially a target-rich area for the development of new therapies for acute OP poisoning. In this manuscript, we discuss what is known about the IMS and studies investigating the use of nicotinic ACh receptor antagonists to prevent or mitigate NMJ dysfunction after acute OP poisoning. PMID:27258847

  7. Monitoring of pesticide residues in vegetarian diet.

    PubMed

    Kumari, Beena; Kathpal, T S

    2009-04-01

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

  8. Determination of organophosphorus pesticides in ginseng by carbon nanotube envelope-based solvent extraction combined with ultrahigh-performance liquid chromatography mass spectrometry.

    PubMed

    Su, Rui; Li, Dan; Wang, Xinghua; Yang, Hongmei; Shi, Xiaoyu; Liu, Shuying

    2016-06-01

    A miniature extraction envelope containing multiwall carbon nanotubes, diatomite, neutral alumina, and anhydrous magnesium sulfate was developed for the solvent extraction of organophosphorus pesticides in dried ginseng. After the powder of dried ginseng sample was introduced into the envelope, the envelope was heat sealed and sonicated in acetonitrile for the extraction and clean-up of analytes. The resulting extracts were analyzed by an ultrahigh-performance liquid chromatograph with an electrospray ion source and a quadrupole orbitrap mass spectrometer (UHPLC-ESI/Q-Orbitrap MS) under target-MS(2) mode, and the analytes were quantified by matrix-match calibration. Finally, the simultaneous identification and quantification of 19 pesticide residues were carried out by the present method. It is noteworthy that in this method the processes of extraction and clean-up for the analytes could be carried out and accomplished in one step. The recoveries and relative standard deviations (RSDs) of analytes were in the range of 82.6-110.8% and 1.0-10.6%, respectively. The limits of detection (LODs) and quantification (LOQs) for analytes were determined to be 0.08-0.29μgkg(-1) and 0.26-0.98μgkg(-1), respectively. Several pesticide residues investigated in this study were found in 4 real samples, with the concentrations lower than the maximum residue limit (0.050mgkg(-1)) established by European Union. PMID:27093495

  9. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Pesticide residue standards. 29.427 Section 29.427... REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.427 Pesticide residue standards. The maximum concentration of residues of the following pesticides allowed in flue-cured or burley tobacco, expressed...

  10. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Pesticide residue standards. 29.427 Section 29.427... REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.427 Pesticide residue standards. The maximum concentration of residues of the following pesticides allowed in flue-cured or burley tobacco, expressed...

  11. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Pesticide residue standards. 29.427 Section 29.427... REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.427 Pesticide residue standards. The maximum concentration of residues of the following pesticides allowed in flue-cured or burley tobacco, expressed...

  12. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Pesticide residue standards. 29.427 Section 29.427... REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.427 Pesticide residue standards. The maximum concentration of residues of the following pesticides allowed in flue-cured or burley tobacco, expressed...

  13. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Pesticide residue standards. 29.427 Section 29.427... REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.427 Pesticide residue standards. The maximum concentration of residues of the following pesticides allowed in flue-cured or burley tobacco, expressed...

  14. Structure-activity predictions of properties of organophosphorus pesticides and chemical agents important for optical detection. Master`s thesis

    SciTech Connect

    Porte, R.E.

    1995-12-01

    This thesis presents the results of an investigation for estimating various physicochemical properties of chemical warfare agents and organophosphorus pesticides. The determination of aqueous solubility, - octanol/water partition coefficients, and alkaline hydrolysis rate constants will be used in the development of a chemical sensor using fiber optic spectroscopy. These three parameters will effect the limit of detection for each compound by limiting the concentration in the detector. The parameters were estimated by linear free energy relationships and quantitative structure activity relationships using experimental data for compounds of similar chemical structure. The results of this thesis showed that the hydrophobic medium represented by 1-octanol did concentrate the OP pesticides but did not significantly concentrate CWA, CWA simulants, or CWA hydrolysis products. Correlations were evaluated for six classes of organophosphorus compounds. The limitation of this approach to predicting physicochemical parameters is not in the molecular descriptors used in the regression equations but in the availability of existing experimental data.

  15. Transformation of organophosphorus pesticides in the presence of aqueous chlorine: kinetics, pathways, and structure-activity relationships.

    PubMed

    Duirk, Stephen E; Desetto, Lisa M; Davis, Gary M

    2009-04-01

    The fate of organophosphorus (OP) pesticides in the presence of aqueous chlorine was investigated under simulated drinking water treatment conditions. Intrinsic rate coefficients were found for the reaction of hypochlorous acid (k(HOCl,OP)) and hypochlorite ion (k(OCl,OP) for several OP pesticides. The reaction of hypochlorous acid (HOCl) with each OP pesticide was relatively rapid near neutral pH, k(HOCl,OP) = 0.86 - 3.56 x 10(6) M(-1)h(-1). HOCI reacts at the thiophosphate (P = S) moiety of the OP pesticide resulting in the formation of the corresponding oxon (P=0), which is more toxic than the parent pesticide. Hypochlorite ion (OCl-) was found not to oxidize OP pesticides but act like a nucleophile accelerating hydrolysis, k(OCl,OP) = 37.3-15910 M(-1)h(-1). Both the k(HOCl,OP) and the k(OCl,OP) were found to correlate well with molecular descriptors within each subgroup of the OP pesticide class. A model was developed to predict the transformation of OP pesticides in the presence of aqueous chlorine. With hydrolysis rate coefficients, the transformation of OP pesticides under drinking water treatment conditions was found to be adequately predicted. The structure-activity relationships and model developed here could be used by risk assessors to determine exposure to OP pesticides and their transformation products in potable water. PMID:19452883

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

    PubMed

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

    2016-01-01

    Based on the highly sensitivity and stable-fluorescence of water-soluble CdTe/CdS core-shell quantum dots (QDs) with broad-specificity DNA aptamers, a novel ratiometric detection strategy was proposed for the sensitive detection of organophosphorus pesticides by capillary electrophoresis with laser-induced fluorescence (CE-LIF). The as-prepared QDs were first conjugated with the amino-modified oligonucleotide (AMO) by amidation reaction, which is partial complementary to the DNA aptamer of organophosphorus pesticides. Then QD-labeled AMO (QD-AMO) was incubated with the DNA aptamer to form QD-AMO-aptamer duplex. When the target organophosphorus pesticides were added, they could specifically bind the DNA aptamer, leading to the cleavage of QD-AMO-aptamer duplex, accompany with the release of QD-AMO. As a result, the ratio of peak height between QD-AMO and QD-AMO-aptamer duplex changed in the detection process of CE-LIF. This strategy was subsequently applied for the detection of phorate, profenofos, isocarbophos, and omethoate with the detection limits of 0.20, 0.10, 0.17, and 0.23μM, respectively. This is the first report about using QDs as the signal indicators for organophosphorus pesticides detection based on broad-specificity DNA aptamers by CE-LIF, thus contributing to extend the scope of application of QDs in different fields. The proposed method has great potential to be a universal strategy for rapid detection of aptamer-specific small molecule targets by simply changing the types of aptamer sequences. PMID:26695234

  17. Biosensor based on Prussian blue nanocubes/reduced graphene oxide nanocomposite for detection of organophosphorus pesticides

    SciTech Connect

    Zhang, Lin; Zhang, Aidong; Du, Dan; Lin, Yuehe

    2012-07-13

    We demonstrate a facile procedure to efficiently prepare Prussian blue nanocubes/reduced graphene oxide (PBNCs/rGO) nanocomposite by directly mixing Fe3+ and [Fe(CN)6]3 in the presence of GO in polyethyleneimine aqueous solution, resulting in a novel acetylcholinesterase (AChE) biosensor for detection of organophosphorus pesticides (OPs). The obtained nanocomposite was characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) microanalysis. It was clearly observed that the nanosheet has been decorated with cubic PB nanoparticles and nearly all the nanoparticles are distributed uniformly only on the surface of the reduced GO. No isolated PB nanoparticles were observed, indicating the strong interaction between PB nanocubes and the reduced GO and the formation of PBNCs/rGO nanocomposite. The obtained PBNCs/rGO based AChE biosensor make the peak potential shift negatively to 220 mV. The AChE biosensor shows rapid response and high sensitivity for detection of monocrotophos. These results suggest that the PBNCs/rGO hybrids nanocomposite exhibited high electrocatalytic activity towards the oxidation of thiocholine, which lead to the sensitive detection of OP pesticides.

  18. Parameters affecting microwave-assisted extraction of organophosphorus pesticides from agricultural soil.

    PubMed

    Fuentes, Edwar; Báez, María E; Labra, Ronnie

    2007-10-26

    This work describes an optimised method for the determination of six representative organophosphorus pesticides (OPPs) (diazinon, parathion, methyl pirimiphos, methyl parathion, ethoprophos, and fenitrothion) in agricultural soils. The method is based on microwave-assisted extraction using a water-methanol modified mixture for desorption and simultaneous partitioning on n-hexane (MAEP), together with gas chromatography-flame photometric detection (GC-FPD). To improve GC-FPD signals (peak intensity and shape) olive oil was used effectively as a "matrix mimic". The optimisation of the extraction method was achieved in two steps: an initial approach through experimental design and principal component analysis where recovery of compounds using a water-methanol mixture ranged from 54 to 77%, and the second one by studying the addition of KH2PO4 to the extracting solution where recoveries were significantly increased, molecular replacing of OPPs from adsorption sites by phosphate being the probable extraction mechanism. Under optimised conditions, recoveries of pesticides from different soils were higher than 73%, except for methyl parathion in some soils, with SD equal or lower than 11% and detection limits ranging from 0.004 to 0.012 microg g(-1). The proposed method was used to determine OPPs in soil samples from different agricultural zones of Chile. PMID:17870081

  19. Earthworm-induced carboxylesterase activity in soil: Assessing the potential for detoxification and monitoring organophosphorus pesticides.

    PubMed

    Sanchez-Hernandez, Juan C; Notario del Pino, J; Domínguez, Jorge

    2015-12-01

    Soil enzyme activities are attracting widespread interest due to its potential use in contaminant breakdown, and as indicators of soil deterioration. However, given the multiple environmental and methodological factors affecting their activity levels, assessment of soil pollution using these biochemical endpoints is still complex. Taking advantage of the well-known stimulatory effect of earthworms on soil microbes, and their associated enzyme activities, we explored some toxicological features of carboxylesterases (CbEs) in soils inoculated with Lumbricus terrestris. A microplate-scale spectrophotometric assay using soil-water suspensions was first optimized, in which kinetic assay parameters (Km, Vmax, dilution of soil homogenate, and duration of soil homogenization) were established for further CbE determinations. Optimal conditions included a soil-to-water ratio of 1:50 (w/v), 30-min of shaking, and 2.5mM of substrate concentration. As expected, CbE activity increased significantly in soils treated with L. terrestris. This bioturbed soil was used for exploring the role of CbE activity as a bioscavenger for organophosphorus (OP) pesticides. Soil treated with two formulations of chlorpyrifos revealed that CbE activity was a significant molecular sink for this pesticide, reducing its impact on soil microbial activity as shown by the unchanged dehydrogenase activity. Dose-dependent curves were adjusted to an exponential kinetic model, and the median ecological dose (ED50) for both pesticide formulations was calculated. ED50 values decreased as the time of pesticide exposure increased (14 d-ED50s=20.4-26.7 mg kg(-1), and 28 d-ED50s=1.8-2.3 mg kg(-1)), which suggested that chlorpyrifos was progressively transformed into its highly toxic metabolite chlorpyrifos-oxon, but simultaneously was inactivated by CbEs. These results were confirmed by in vitro assays that showed chlorpyrifos-oxon was a more potent CbE inhibitor (IC50=35.5-4.67 nM) than chlorpyrifos (0.41-0.84

  20. Sensitive Detection of Organophosphorus Pesticides in Medicinal Plants Using Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction Combined with Sweeping Micellar Electrokinetic Chromatography.

    PubMed

    Wei, Jin-Chao; Hu, Ji; Cao, Ji-Liang; Wan, Jian-Bo; He, Cheng-Wei; Hu, Yuan-Jia; Hu, Hao; Li, Peng

    2016-02-01

    A simple, rapid, and sensitive method using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) combined with sweeping micellar electrokinetic chromatography (sweeping-MEKC) has been developed for the determination of nine organophosphorus pesticides (chlorfenvinphos, parathion, quinalphos, fenitrothion, azinphos-ethyl, parathion-methyl, fensulfothion, methidathion, and paraoxon). The important parameters that affect the UA-DLLME and sweeping efficiency were investigated. Under the optimized conditions, the proposed method provided 779.0-6203.5-fold enrichment of the nine pesticides compared to the normal MEKC method. The limits of detection ranged from 0.002 to 0.008 mg kg(-1). The relative standard deviations of the peak area ranged from 1.2 to 6.5%, indicating the good repeatability of the method. Finally, the developed UA-DLLME-sweeping-MEKC method has been successfully applied to the analysis of the investigated pesticides in several medicinal plants, including Lycium chinense, Dioscorea opposite, Codonopsis pilosula, and Panax ginseng, indicating that this method is suitable for the determination of trace pesticide residues in real samples with complex matrices. PMID:26758524

  1. Chronic cumulative risk assessment of the exposure to organophosphorus, carbamate and pyrethroid and pyrethrin pesticides through fruit and vegetables consumption in the region of Valencia (Spain).

    PubMed

    Quijano, Leyre; Yusà, Vicent; Font, Guillermina; Pardo, Olga

    2016-03-01

    In the present study, the chronic cumulative exposure to organophosphorus (OPs), carbamates (CBs) and pyrethroid and pyrethrin (PPs) pesticides in the region of Valencia through fruit and vegetables consumption is presented. A total of 752 samples and 84 pesticides were studied of which, 52 were OPs, 23 CBs and 9 PPs. Residue data were derived from the Valencia Region monitoring program 2007-2011 and food consumption levels from a questionnaire-based dietary survey conducted in 2010 in the same area. The relative potency factor (RPFs) approach was used to estimate chronic cumulative dietary exposure to OPs, CBs and PPs using acephate, oxamyl and deltamethrin as index compounds, respectively. The exposure was estimated using a deterministic approach and two scenarios were assumed for left-censored results: the lower-bound (LB) scenario, in which unquantified results (below the limit of quantification (LOQ)) were set to zero and the upper-bound (UB) scenario, in which unquantified results were set to the LOQ. Results demonstrate that the chronic exposure of the young (<16 years) and adult (≥ 16 years) population to pesticides through fruits and vegetables is under control (even at high or frequent consumption of fruits and vegetables), for the three groups of pesticides. PMID:26774911

  2. Sensitivity of blood-clotting factors and digestive enzymes to inhibition by organophosphorus pesticides.

    PubMed

    Quistad, G B; Casida, J E

    2000-01-01

    Organophosphorus pesticide toxicology is normally evaluated in relation to inhibition of cholinesterases (acetyl and butyryl), neuropathy target esterase, and carboxylesterases, with less attention given to other physiologically important hydrolases. This study considers the relative organophosphate sensitivities of the aforementioned serine hydrolases compared with purified blood-clotting factors (thrombin, plasmin, and kallikrein) and digestive enzymes (alpha-chymotrypsin, trypsin, and elastase), assayed under similar conditions. Inhibitors that we examined are organophosphorus insecticides or their activated metabolites (paraoxon, chlorpyrifos oxon, and profenofos) and other toxicants (phenyl saligenin cyclic phosphonate and tribufos) for comparison with values that are found in the literature for the fluorophosphonates (isoflurophate and sarin). Thrombin is the most sensitive blood-clotting factor with IC-50 values of 19 to 160 microM for tribufos, the cyclic phosphonate, isoflurophate, and profenofos; plasmin and kallikrein are less affected (IC-50 >100 microM). Alpha-Chymotrypsin, trypsin, and elastase are most sensitive to the cyclic phosphonate (IC-50 1.3-15 microM) and less so to isoflurophate, sarin, and profenofos (IC-50 values from 3.6 to greater than 100 microM). The cholinesterases, carboxylesterase, and neuropathy target esterase are the most sensitive to inhibition with IC-50 values for the insecticides of less than 0.001 to 0.6, 0.002 to 0.009, and 0.15 to 100 microM, respectively. The generally low potency of these organophosphates for blood-clotting factors and digestive enzymes suggests that associated toxic effects are unlikely at sublethal doses. PMID:10561082

  3. Monitoring of pesticide residues in Egyptian fruits and vegetables during 1997.

    PubMed

    Dogheim, S M; El-Marsafy, A M; Salama, E Y; Gadalla, S A; Nabil, Y M

    2002-11-01

    A total of 2318 domestic samples of different types of fruits and vegetables were collected from eight Egyptian local markets in six different regions of the country. All samples were examined for residues of 54 pesticides, including organophosphorus, organonitrogen, organohalogen and certain pyrethroides. However, dithiocarbamates were analysed in only 318 samples. Overall, 81.5% of the samples had no detectable pesticide residues. Of the contaminated samples, 18.5% contained detectable residues and 1.9% exceeded their maximum residue limits (MRLs). Root and leafy vegetables showed the lowest contamination rates (1.9 and 4.7%, respectively), slightly exceeding the MRLs in leafy vegetables. However, fruit samples showed a slightly higher proportion of contamination than vegetables (29 and 14.3%, respectively). Fruit also exhibited a higher level of violation than vegetables (2.3 and 1.9%, respectively). The contamination and violation rates were lower than the percentages recorded in previous years' monitoring studies. Dicofol and dimethoate were the most frequently occurring pesticide residues at 5.1 and 5.0%, respectively. Dimethoate showed higher violation levels (0.69%). However, dicofol showed a slight violation rate (0.09%) which indicates good agricultural practices for dicofol use. Dithiocarbamates residues were found in 21 of the 318 samples analysed, which when expressed as a percentage contamination was 6.6%, and only one sample exceeded the MRL. PMID:12456272

  4. Prenatal Organophosphorus Pesticide Exposure and Child Neurodevelopment at 24 Months: An Analysis of Four Birth Cohorts

    PubMed Central

    Engel, Stephanie M.; Bradman, Asa; Wolff, Mary S.; Rauh, Virginia A.; Harley, Kim G.; Yang, Jenny H.; Hoepner, Lori A.; Barr, Dana Boyd; Yolton, Kimberly; Vedar, Michelle G.; Xu, Yingying; Hornung, Richard W.; Wetmur, James G.; Chen, Jia; Holland, Nina T.; Perera, Frederica P.; Whyatt, Robin M.; Lanphear, Bruce P.; Eskenazi, Brenda

    2015-01-01

    Background: Organophosphorus pesticides (OPs) are used in agriculture worldwide. Residential use was common in the United States before 2001. Objectives: We conducted a pooled analysis of four birth cohorts (children’s centers; n = 936) to evaluate associations of prenatal exposure to OPs with child development at 24 months. Methods: Using general linear models, we computed site-specific and pooled estimates of the association of total dialkyl (ΣDAP), diethyl (ΣDEP), and dimethylphosphate (ΣDMP) metabolite concentrations in maternal prenatal urine with mental and psychomotor development indices (MDI/PDI) and evaluated heterogeneity by children’s center, race/ethnicity, and PON1 genotype. Results: There was significant heterogeneity in the center-specific estimates of association for ΣDAP and ΣDMP and the MDI (p = 0.09, and p = 0.05, respectively), as well as heterogeneity in the race/ethnicity-specific estimates for ΣDAP (p = 0.06) and ΣDMP (p = 0.02) and the MDI. Strong MDI associations in the CHAMACOS population per 10-fold increase in ΣDAP (β = –4.17; 95% CI: –7.00, –1.33) and ΣDMP (β = –3.64; 95% CI: –5.97, –1.32) were influential, as were associations among Hispanics (β per 10-fold increase in ΣDAP = –2.91; 95% CI: –4.71, –1.12). We generally found stronger negative associations of ΣDAP and ΣDEP with the 24-month MDI for carriers of the 192Q PON1 allele, particularly among blacks and Hispanics. Conclusions: Data pooling was complicated by center-related differences in subject characteristics, eligibility, and changes in regulations governing residential use of OPs during the study periods. Pooled summary estimates of prenatal exposure to OPs and neurodevelopment should be interpreted with caution because of significant heterogeneity in associations by center, race/ethnicity, and PON1 genotype. Subgroups with unique exposure profiles or susceptibilities may be at higher risk for adverse neurodevelopment following prenatal

  5. Persistent organochlorine pesticide residues in animal feed.

    PubMed

    Nag, Subir Kumar; Raikwar, Mukesh K

    2011-03-01

    Animal products like milk and meat are often found to be contaminated with residues of persistent pesticides and other toxic substances. The major source of entry of these compounds to animal body is the contaminated feed and fodder. So, unless the residues are managed at this stage, it is very difficult to prevent contamination in milk and meat. Therefore, the status of residue level of most persistent organochlorinated pesticides (OCP) in feed and fodder should be monitored regularly. The frequency of occurrence and contamination levels of OCP residues in different kinds of animal concentrate feed and straw samples collected from Bundelkhand region of India were determined. Out of 533 total samples, 301 i.e. 56.47% samples were positive containing residues of different OCPs like hexachlorocyclohexane (HCH) isomers, dichlorodiphenyltrichloroethane (DDT) complex, endosulfan and dicofol. Among different HCH isomers, the mean concentration of β-HCH was highest, and total HCH varied from 0.01 to 0.306 mg kg(-1). In case of DDT complex, i.e. DDD, DDE and DDT, the concentration ranged between 0.016 and 0.118 mg kg(-1) and the pp(|) isomers were more frequently encountered than their op(|) counterparts. Endosulfan was also found in some samples in concentration ranging from 0.009 to 0.237 mg/kg, but dicofol could be recorded in very few samples. Although feed samples were found to contain OC residues, after comparing their levels in positive samples with the limiting values of respective pesticides, only very few were found to exceed the threshold level. Otherwise, they were mostly within safe limits. PMID:20443138

  6. Development of a biotinylated broad-specificity single-chain variable fragment antibody and a sensitive immunoassay for detection of organophosphorus pesticides.

    PubMed

    Zhao, Fengchun; Tian, Yuan; Wang, Huimin; Liu, Jiye; Han, Xiao; Yang, Zhengyou

    2016-09-01

    Organophosphorus pesticides (OPs) are the most widely used pesticides in agriculture, and OP residues have been broadly reported in food and environmental samples. The aim of this study is to develop a recombinant antibody-based broad-specificity immunoassay for OPs. A phage display library was prepared from a mouse pre-immunized with a generic immunogen of OPs, and a single-chain variable fragment (scFv) antibody was selected. The selected scFv antibody was fused with biotin acceptor domain (BAD) and overexpressed as an inclusion body in Escherichia coli BL21 (DE3). Then, the protein was refolded by stepwise urea gradient dialysis and biotinylated in vitro by E. coli biotin ligase (BirA). Subsequently, the scFv-BAD protein was purified from the biotinylated system with high yield (66.7 mg L(-1)) and confirmed by SDS-PAGE and Western blot. Based on the biotinylated scFv-BAD, a sensitive and broad-specificity competitive indirect enzyme-linked immunosorbent assay (ciELISA) for detection of OPs was developed. The cross-reactivity (CR) studies demonstrated that the ciELISA described here exhibited the broadest detection spectrum for OPs up to now, and 30 OPs could be determined with 50 % inhibition value (IC50) values ranging from 19.4 to 515.2 ng mL(-1). Moreover, the developed ciELISA was used for the recovery study of the spiked samples and showed satisfactory recoveries. Graphical Abstract Schematic diagram of the development of biotinylated broad-specificity single-chain variable fragment antibody-based immunoassay for organophosphorus pesticides. PMID:27411546

  7. Method for the determination of organophosphorus and pyrethroid pesticides in food via gas chromatography with electron-capture detection.

    PubMed

    Hunter, Ronald E; Riederer, Anne M; Ryan, P Barry

    2010-02-10

    We have developed a rapid, high-throughput, accurate, multiresidue method for the analysis of selected organophosphorus and pyrethroid pesticides in a variety of food samples suitable for use in public health and epidemiologic investigations of high-use pesticides using modifications of existing methods. The procedure involves a pesticide extraction from the food sample with acetonitrile followed by a salting-out with NaCl and cleanup of the extract with a multilayer solid-phase extraction cartridge composed of a Supelclean ENVI-CARB-II top layer and a primary-secondary amine bottom layer separated by a polyethylene frit. To evaluate the method, we performed fortification studies at 50, 100, and 200 ng/g for 3 organophosphorus and 4 pyrethroid pesticides in 16 different foods. Instrumental analysis was carried out by capillary gas chromatography with electron-capture detection (GC-ECD). Confirmatory analysis was performed by GC coupled with mass spectrometry (MS) in the selected-ion monitoring (SIM) mode. Average recoveries for each fortification level ranged from 49 to 146% with 80% of recoveries between 80 and 120%. PMID:20073464

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

    PubMed

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

    2015-01-01

    The objective of this study was to determine the levels of pesticides in the fish Prochilodus costatus caught in São Francisco River, one of most important rivers in Brazil. Thirty-six fish were captured in three different areas, and samples of the dorsal muscle and pooled viscera were collected for toxicological analysis. We evaluated the presence of 150 different classes of insecticides, fungicides, herbicides and acaricides by multiresidue analysis technique using liquid chromatography-tandem mass spectrometry (LC-MS/MS), with the limit of detection of 5 ppb. In this study, organophosphorus and carbamate pesticides were detected at the highest levels in the caught fish. Among the 41 organophosphorus pesticides surveyed, nine types were detected (chlorpyrifos, diazinon, dichlorvos, disulfoton, ethion, etrimfos, phosalone, phosmet and pyrazophos) in the muscle, viscera pool, or both in 22 (61.1%) fish. Sampled tissues of 20 (55.6%) fish exhibited at least one of the eight evaluated carbamate pesticides and their metabolites: aldicarb, aldicarb sulfoxide, carbaryl, carbofuran, carbosulfan, furathiocarb, methomyl and propoxur. Fungicides (carbendazim, benalaxyl, kresoxim-methyl, trifloxystrobin, pyraclostrobin and its metabolite BF 500 pyraclostrobin), herbicides (pyridate and fluasifop p-butyl), acaricide (propargite) and pyrethroid (flumethrin) were also detected. In conclusion, P. costatus fish caught in the São Francisco River contained residues of 17 different pesticides, in both muscles and the viscera pool, indicating heavy environmental contamination by pesticides in the study area. PMID:25844860

  9. Antiandrogenic activity and metabolism of the organophosphorus pesticide fenthion and related compounds.

    PubMed Central

    Kitamura, Shigeyuki; Suzuki, Tomoharu; Ohta, Shigeru; Fujimoto, Nariaki

    2003-01-01

    We investigated the endocrine-disrupting actions of the organophosphorus pesticide fenthion and related compounds and the influence of metabolic transformation on the activities of these compounds. Fenthion acted as an antagonist of the androgenic activity of dihydrotestosterone (10(-7)M) in the concentration range of 10(-6)-10(-4)M in an androgen-responsive element-luciferase reporter-responsive assay using NIH3T3 cells. The antiandrogenic activity of fenthion was similar in magnitude to that of flutamide. Fenthion also tested positive in the Hershberger assay using castrated male rats. Marked estrogenic and antiestrogenic activities of fenthion and related compounds were not observed in MCF-7 cells. When fenthion was incubated with rat liver microsomes in the presence of NADPH, the antiandrogenic activity markedly decreased, and fenthion sulfoxide was detected as a major metabolite. The oxidase activity toward fenthion was exhibited by cytochrome P450 and flavin-containing monooxygenase. Fenthion sulfoxide was negative in the screening test for antiandrogens, as was fenthion sulfone. However, when fenthion sulfoxide was incubated with liver cytosol in the presence of 2-hydroxypyrimidine, an electron donor of aldehyde oxidase, the extract of the incubation mixture exhibited antiandrogenic activity. In this case, fenthion was detected as a major metabolite of the sulfoxide. Metabolic interconversion between fenthion and fenthion sulfoxide in the body seems to maintain the antiandrogenic activity. PMID:12676606

  10. Computational Enzymology and Organophosphorus Degrading Enzymes: Promising Approaches Toward Remediation Technologies of Warfare Agents and Pesticides.

    PubMed

    Ramalho, Teodorico C; de Castro, Alexandre A; Silva, Daniela R; Silva, Maria Cristina; Franca, Tanos C C; Bennion, Brian J; Kuca, Kamil

    2016-01-01

    The re-emergence of chemical weapons as a global threat in hands of terrorist groups, together with an increasing number of pesticides intoxications and environmental contaminations worldwide, has called the attention of the scientific community for the need of improvement in the technologies for detoxification of organophosphorus (OP) compounds. A compelling strategy is the use of bioremediation by enzymes that are able to hydrolyze these molecules to harmless chemical species. Several enzymes have been studied and engineered for this purpose. However, their mechanisms of action are not well understood. Theoretical investigations may help elucidate important aspects of these mechanisms and help in the development of more efficient bio-remediators. In this review, we point out the major contributions of computational methodologies applied to enzyme based detoxification of OPs. Furthermore, we highlight the use of PTE, PON, DFP, and BuChE as enzymes used in OP detoxification process and how computational tools such as molecular docking, molecular dynamics simulations and combined quantum mechanical/molecular mechanics have and will continue to contribute to this very important area of research. PMID:26898655

  11. Evaluation of two commercial capillary columns for the enantioselective gas chromatographic separation of organophosphorus pesticides.

    PubMed

    Fidalgo-Used, Natalia; Blanco-González, Elisa; Sanz-Medel, Alfredo

    2006-12-15

    The separation of the enantiomers of 13 organophosphorus pesticides (OPPs) has been investigated by gas chromatography (GC) with flame ionisation detection (FID) using two different commercially available chiral columns, Chirasil-Val (l-valine-tert-butylamide) and CP-Chirasil-Dex CB (heptakis (2,3,6-tri-O-metil)-beta-cyclodextrin). Using the Chirasil-Val column no chiral resolution was obtained for the OPPs investigated under any tested experimental condition. The use of the CP-Chirasil-Dex CB stationary phase enabled good individual enantiomeric separation of two OPPs, ruelene and trichlorfon and partial separation of naled, chloretoxyphos, isophenphos and metamidophos. Also, the obtained chromatographic results showed that Chirasil-Dex could resolve enantiomers through the combination of different mechanism (e.g. formation of inclusion complexes and/or interactions outside the cyclodextrin cavity). Under optimised conditions, precision, linearity range and detection limits were evaluated for the enantiomers of ruelene and trichlorfon using CP-Chirasil-Dex CB column and electron capture detection (ECD). By using the GC-ECD method the enantiomers of these OPPs could be satisfactorily detected at very low concentration levels. The detection limits observed were 1.5ngmL(-1) and 11.5ngmL(-1) for the enantiomers of trichlorfon and ruelene, respectively. PMID:18970881

  12. A ratiometric fluorescent quantum dots based biosensor for organophosphorus pesticides detection by inner-filter effect.

    PubMed

    Yan, Xu; Li, Hongxia; Han, Xiaosong; Su, Xingguang

    2015-12-15

    In this work, we develop a novel and sensitive sensor for the detection of organophosphorus pesticides based on the inner-filter effect (IFE) between gold nanoparticles (AuNPs) and ratiometric fluorescent quantum dots (RF-QDs). The RF-QDs has been designed by hybridizing two differently colored CdTe QDs, in which the red emissive QDs entrapped in the silica sphere acting as the reference signal, and the green emissive QDs covalently attached on the silica surface serving as the response signal.The fluorescence of RF-QDs could be quenched by AuNPs based on IFE. Protamine could effectively turn on the fluorescence due to the electrostatic attraction between protamine and AuNPs. Trypsin can easily hydrolyze protamine, leading to the quench of the fluorescence. Then, the fluorescence could be recovered again by the addition of parathion-methyl (PM) which could inhibit the activity of trypsin. By measuring the fluorescence of RF-QDs, the inhibition efficiency of PM to trypsin activity was evaluated. Under the optimized conditions, the inhibition efficiency was proportional to the logarithm of PM concentration in the range of 0.04-400 ng mL(-1), with a detection limit of 0.018 ng mL(-1). Furthermore, the simple and convenient method had been used for PM detection in environmental and agricultural samples with satisfactory results. PMID:26143468

  13. Activity-Based Protein Profiling of Organophosphorus and Thiocarbamate Pesticides Reveals Multiple Serine Hydrolase Targets in Mouse Brain

    PubMed Central

    NOMURA, DANIEL K.; CASIDA, JOHN E.

    2010-01-01

    Organophosphorus (OP) and thiocarbamate (TC) agrochemicals are used worldwide as insecticides, herbicides, and fungicides, but their safety assessment in terms of potential off-targets remains incomplete. In this study, we used a chemoproteomic platform, termed activity-based protein profiling, to broadly define serine hydrolase targets in mouse brain of a panel of 29 OP and TC pesticides. Among the secondary targets identified, enzymes involved in degradation of endocannabinoid signaling lipids, monoacylglycerol lipase and fatty acid amide hydrolase, were inhibited by several OP and TC pesticides. Blockade of these two enzymes led to elevations in brain endocannabinoid levels and dysregulated brain arachidonate metabolism. Other secondary targets include enzymes thought to also play important roles in the nervous system and unannotated proteins. This study reveals a multitude of secondary targets for OP and TC pesticides and underscores the utility of chemoproteomic platforms in gaining insights into biochemical pathways that are perturbed by these toxicants. PMID:21341672

  14. Microwave accelerated selective Soxhlet extraction for the determination of organophosphorus and carbamate pesticides in ginseng with gas chromatography/mass spectrometry.

    PubMed

    Zhou, Ting; Xiao, Xiaohua; Li, Gongke

    2012-07-01

    Microwave accelerated selective Soxhlet extraction (MA-SSE), a novel selective extraction technique, was investigated in this study. A Soxhlet extraction system containing a glass filter was designed as an extractor. During the procedure of MA-SSE, both the target analytes and the interfering components were extracted from the sample into the extraction solvent enhanced by microwave irradiation. After the solvent flowed though the sorbent, the interfering components were adsorbed by the sorbent, and the target analytes remaining in the solvent were collected in the extraction bottle. No cleanup or filtration was required after extraction. The efficiency of the MA-SSE approach was demonstrated in the determination of organophosphorus and carbamate pesticide residues in ginseng by gas chromatography/mass spectrometry (GC/MS). Under the optimized conditions, low limits of detection (0.050-0.50 μg/kg) were obtained. The recoveries were in the range of 72.0-110.1% with relative standard deviations less than 7.1%. Because of the effect of microwave irradiation, MA-SSE showed significant advantage compared with other extraction techniques. The sorbent used in this study showed good cleanup ability. The mechanism of MA-SSE was demonstrated to be based on the rupture of the cell walls according to the structural changes of ginseng samples. On the basis of the results, MA-SSE as a simple and effective sample preparation technique for the analysis of pesticide residues in complex matrixes shows great promise. PMID:22686368

  15. Research of pesticide residues on fruit by terahertz spectroscopy technology

    NASA Astrophysics Data System (ADS)

    Ma, Yehao; Wang, Qiang; Wang, Xiaowei; Wang, Huali

    2011-11-01

    Pesticide residues on the fruit skin are measured by terahertz time-domain spectroscopy (THz-TDS) in 0.2-1.3THz. Pesticide is mainly residues for fruit, which threatens health of human, so the research about the fruit residues is absolutely important. In the experiment, a kind of pesticide carbendazim, orange, and the mixture of them are measured by THz-TDS, and then calculate absorption spectrums through Fourier transform and Fresnel formula. Experiment results indicate that THz-TDS is an effective tool for the measurement of pesticide residues on the fruit skin.

  16. Simultaneous preconcentration of polar and non-polar organophosphorus pesticides from water samples by using a new sorbent based on mesoporous silica.

    PubMed

    Soutoudehnia Korrani, Zahra; Wan Ibrahim, Wan Aini; Rashidi Nodeh, Hamid; Aboul-Enein, Hassan Y; Sanagi, Mohd Marsin

    2016-03-01

    A new mesoporous silica based on the sol-gel material cyanopropyltriethoxysilane (CNPrTEOS) was successfully synthesized by the hydrolysis and condensation of CNPrTEOS in the presence of ammonium solution as catalyst and methanol as solvent. It was used as a solid-phase extraction sorbent for the simultaneous extraction of three organophosphorus pesticides, namely, polar dicrotophos and non-polar diazinon and chlorpyrifos. Analysis was performed using high-performance liquid chromatography with UV detection. CNPrTEOS was characterized by FTIR spectroscopy, field-emission scanning electron microscopy and nitrogen gas adsorption. The surface area and average pore diameter of the optimum sol-gel CNPrTEOS are 379 m(2) /g and 4.7 nm (mesoporous), respectively. The proposed solid-phase extraction based on CNPrTEOS exhibited good linearity in the range of 0.8-100 μg/L, satisfactory precision (1.15-3.82%), high enrichment factor (800) and low limit of detection (0.072-0.091 μg/L). The limits of detection obtained using the proposed solid-phase extraction method are well below the maximum residue limit set by European Union and are also lower (13.6-48.5×) than that obtained by using a commercial CN-SPE cartridge (0.98-4.41 μg/L). The new mesoporous sol-gel CNPrTEOS showed promising alternative as SPE sorbent material for the simultaneous extraction of polar and non-polar organophosphorus pesticides. PMID:26768840

  17. Pesticide residues in imported, organic, and "suspect" fruits and vegetables.

    PubMed

    Winter, Carl K

    2012-05-01

    Consumers are frequently urged to avoid imported foods as well as specific fruits and vegetables due to health concerns from pesticide residues and are often encouraged to choose organic fruits and vegetables rather than conventional forms. Studies have demonstrated that while organic fruits and vegetables have lower levels of pesticide residues than do conventional fruits and vegetables, pesticide residues are still frequently detected on organic fruits and vegetables; typical dietary consumer exposure to pesticide residues from conventional fruits and vegetables does not appear to be of health significance. Similarly, research does not demonstrate that imported fruits and vegetables pose greater risks from pesticide residues than do domestic fruits and vegetables or that specific fruits and vegetables singled out as being the most highly contaminated by pesticides should be avoided in their conventional forms. PMID:22335627

  18. Dietary exposure of Hong Kong adults to pesticide residues: results of the first Hong Kong Total Diet Study.

    PubMed

    Wong, Waiky W K; Yau, Arthur T C; Chung, Stephen W C; Lam, Chi-ho; Ma, Stephanie; Ho, Y Y; Xiao, Ying

    2014-01-01

    The use of pesticides and other chemicals has become a common practice in modern agriculture to enhance and stabilise crop yield, protect the nutritional integrity of food, facilitate food storage to assure year-round supplies, and provide attractive and appealing food products. With the adoption of strict good agricultural practice (GAP), only minimal amounts of pesticide residues should remain on the crops or in connected foods of animal origin up the food chain. To assess their associated health risk to local people, the dietary exposure of Hong Kong adults to residues of four groups of pesticides or their metabolites - organophosphorus pesticides (OPPs), carbamates, pyrethrins and pyrethroids, and dithiocarbamate (DTC) metabolites - is estimated in the first Hong Kong Total Diet Study (TDS). A total of 150 commonly consumed food items were collected and prepared "as consumed". A total of 600 composite food samples were analysed for 85 pesticides or their metabolites by liquid chromatography-tandem mass spectrometry (LC-MS/MS). These pesticides were primarily found at low levels (highest mean = 350 μg kg⁻¹) in food samples of plant origin such as vegetables and fruits. Dietary exposures to pesticide residues were estimated based on the analytical results and the food consumption data of the local residents. The estimated dietary exposures of Hong Kong adults to all individual pesticides were well below their respective acceptable daily intakes (ADIs). The percentage contributions of the estimated mean and 95th percentile dietary exposures to the ADIs of individual pesticides were <6% and <24% for the OPPs, <1% for the carbamates and pyrethrins and pyrethroids, and <1% and <4% for the DTC metabolites, respectively. The findings indicate that dietary exposures to all the pesticide residues analysed in this study were unlikely to pose unacceptable health risks to the Hong Kong population. PMID:24588687

  19. Non-specific biodegradation of the organophosphorus pesticides, cadusafos and ethoprophos, by two bacterial isolates.

    PubMed

    Karpouzas, Dimitrios G; Fotopoulou, Anastasia; Menkissoglu-Spiroudi, Urania; Singh, Brajesh K

    2005-08-01

    An enrichment culture technique was used for the isolation of microorganisms responsible for the enhanced biodegradation of the nematicide cadusafos in soils from a potato monoculture area in Northern Greece. Mineral salts medium supplemented with nitrogen (MSMN), where cadusafos (10 mg l(-1)) was the sole carbon source, and soil extract medium (SEM) were used for the isolation of cadusafos-degrading bacteria. Two pure bacterial cultures, named CadI and CadII, were isolated and subsequently characterized by sequencing of 16S rRNA genes. Isolate CadI showed 97.4% similarity to the 16S rRNA gene of a Flavobacterium strain, unlike CadII which showed 99.7% similarity to the 16S rRNA gene of a Sphingomonas paucimobilis. Both isolates rapidly metabolized cadusafos in MSMN and SEM within 48 h with concurrent population growth. This is the first report for the isolation and characterization of soil bacteria with the ability to degrade rapidly cadusafos and use it as a carbon source. Degradation of cadusafos by both isolates was accelerated when MSMN was supplemented with glucose. In contrast, addition of succinate in MSMN marginally reduced the degradation of cadusafos. Both isolates were also able to degrade completely ethoprophos, a nematicide chemical analog of cadusafos, but did not degrade the other organophosphorus nematicides tested such as isazofos and isofenphos. Inoculation of a soil freshly treated with cadusafos or ethoprophos (10 mg l(-1)) with high inoculum densities (4.3 x 10(8) cells g(-1)) of Sphingomonas paucimobilis resulted in the rapid degradation of both nematicides. These results indicate the potential of this bacterium to be used in the clean-up of contaminated pesticide waste in the environment. PMID:16329956

  20. Determination of organophosphorus pesticides in soil by dispersive liquid-liquid microextraction and gas chromatography.

    PubMed

    Yang, Zhonghua; Liu, Yu; Liu, Donghui; Zhou, Zhiqiang

    2012-01-01

    In this article, a rapid and sensitive sample pretreatment technique for the determination of organophosphorus pesticides (OPPs) in soil samples is developed by using dispersive liquid-liquid microextraction (DLLME) combined with gas chromatography-flame photometric detection. Experimental conditions, including the kind of extraction and disperser solvent and their volumes, the extraction time, and the salt addition, are investigated, and the following experiment factors are used: 20 µL chlorobenzene as the extraction solvent; 1.0 mL acetonitrile as the disperser solvent; no addition of salt; and an extraction time of 1 min. Under the optimum conditions, the linearities for the three target OPPs (ethoprophos, chlorpyriphos, and profenofos) are obtained by five points in the concentration range of 2.5-1500 µg/kg, and three replicates are used for each point. Correlation coefficients vary from 0.9987 to 0.9997. The repeatability is tested by spiking soil samples at a concentration level of 5.0 µg/kg. The relative standard deviation (n = 3) varied between 2.0% and 6.6%. The limits of detection, based on a signal-to-noise ratio (S/N) of 3, range from 200 to 500 pg/g. This method is applied to the analysis of the spiked samples S1, S2, and S3, which are collected from the China Agriculture University's orchard, lawn, and garden, respectively. The recoveries for each target analyte are in the range between 87.9% and 108.0%, 87.4% and 108.0%, and 86.7% and 107.2%, respectively. PMID:22291051

  1. Determination of Organophosphorus Pesticides in Soil by Dispersive Liquid–Liquid Microextraction and Gas Chromatography

    PubMed Central

    Yang, Zhonghua; Liu, Yu; Liu, Donghui; Zhou, Zhiqiang

    2012-01-01

    In this article, a rapid and sensitive sample pretreatment technique for the determination of organophosphorus pesticides (OPPs) in soil samples is developed by using dispersive liquid–liquid microextraction (DLLME) combined with gas chromatography–flame photometric detection. Experimental conditions, including the kind of extraction and disperser solvent and their volumes, the extraction time, and the salt addition, are investigated, and the following experiment factors are used: 20 µL chlorobenzene as the extraction solvent; 1.0 mL acetonitrile as the disperser solvent; no addition of salt; and an extraction time of 1 min. Under the optimum conditions, the linearities for the three target OPPs (ethoprophos, chlorpyriphos, and profenofos) are obtained by five points in the concentration range of 2.5–1500 µg/kg, and three replicates are used for each point. Correlation coefficients vary from 0.9987 to 0.9997. The repeatability is tested by spiking soil samples at a concentration level of 5.0 µg/kg. The relative standard deviation (n = 3) varied between 2.0% and 6.6%. The limits of detection, based on a signal-to-noise ratio (S/N) of 3, range from 200 to 500 pg/g. This method is applied to the analysis of the spiked samples S1, S2, and S3, which are collected from the China Agriculture University's orchard, lawn, and garden, respectively. The recoveries for each target analyte are in the range between 87.9% and 108.0%, 87.4% and 108.0%, and 86.7% and 107.2%, respectively. PMID:22291051

  2. Pesticide residues in honey samples from Himachal Pradesh (India).

    PubMed

    Choudhary, Amit; Sharma, Duni C

    2008-05-01

    Honey, being a natural product manufactured by honey bees is considered to be free from any extraneous material. The over-reliance on pesticides caused several environmental problems including pesticide residues in food. This constitutes a potential risk for human health, because of their sub acute and chronic toxicity. Therefore this study was carried out to know the extent of pesticide residue in honey produced in the various parts of Himachal Pradesh. Among different pesticides analysed in honey; HCH and its isomers were the most frequently detected followed by DDT and its isomers. Of the studied synthetic pyrethroids, only cypermethrin was found in honey samples. Residues of organophosphates viz. acephate, chlorpyriphos, ethion and monocrotophos were not detected, however malathion's residue was found exceeding the MRL (5 ppb) proposed by the Ministry of Commerce, Government of India. More over honey from natural vegetation contained lesser residues. It can be concluded that honey from Himachal Pradesh had low pesticide residues. PMID:18506381

  3. [Organochlorine pesticide residues in human adipose tissue in Costa Rica].

    PubMed

    Barquero, M; Constenla, M A

    1986-06-01

    Organochlorine pesticide residues were found in 82 samples of human adipose material from 82 surgical cases in 16 Costa Rica hospitals. Identification was made by gas-liquid chromatography. The highest pesticide concentration was that of DDT and its metabolites (33.16 micrograms/g). Residues of almost all commercial pesticides were also found. Concentrations of alpha-chlordane. Aldrin and Polychlorinated biphenyls were not significant. PMID:2445007

  4. Multi-walled carbon nanotubes as efficient solid-phase extraction materials of organophosphorus pesticides from apple, grape, orange and pineapple fruit juices.

    PubMed

    Ravelo-Pérez, Lidia M; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Angel

    2008-11-21

    Multi-walled carbon nanotubes (MWCNTs) have been used for the first time as solid-phase extraction (SPE) sorbents for the extraction of eight organophosphorus pesticides (i.e. ethoprophos, diazinon, chlorpyriphos-methyl, fenitrothion, malathion, chlorpyriphos, fenamiphos and buprofezin) from different commercial fruit juices (i.e. apple, grape, orange and pineapple). The developed method, which involves SPE and direct gas chromatography with nitrogen phosphorus detection analysis, is very fast, simple and cheap: only 1:1 dilution with Milli-Q water and pH adjustment to 6.0 of 10 mL of juice is necessary prior to a quick MWCNTs-SPE procedure that used only 40 mg of stationary phase (MWCNTs of 10-15 nm o.d., 2-6 nm i.d. and 0.1-10 microm length). Mean recovery values were above 73% for all the pesticides and fruit juices (between 77 and 101% for apple juice, 75 and 103% for grape juice, 73 and 103% for orange juice and 73 and 93% for pineapple juice) with a relative standard deviation (RSD) lower than 8.5% in all cases. Matrix matched calibration was carried out for each sample matrix since statistical differences between the calibration curves constructed is pure solvent and in the reconstructed juice extracts were found. Limits of detection ranged between 1.85 and 7.32 microg/L (which also represents LODs between 1.85 and 7.34 microg/kg) well below the European Union maximum residue limits for the raw fruits. The proposed method, which is demonstrated to be quick, cheap, accurate and highly selective, was also applied to the analysis of this group of pesticides in several commercial juices in which none of the selected pesticides were found. PMID:18849040

  5. Novel restricted access materials combined to molecularly imprinted polymers for selective solid-phase extraction of organophosphorus pesticides from honey.

    PubMed

    He, Juan; Song, Lixin; Chen, Si; Li, Yuanyuan; Wei, Hongliang; Zhao, Dongxin; Gu, Keren; Zhang, Shusheng

    2015-11-15

    A novel restricted access materials (RAM) combined to molecularly imprinted polymers (MIPs), using malathion as template molecule and glycidilmethacrylate (GMA) as pro-hydrophilic co-monomer, were prepared for the first time. RAM-MIPs with hydrophilic external layer were characterized by scanning electron microscopy and recognition and selectivity properties were compared with the restricted access materials-non-molecularly imprinted polymers (RAM-NIPs) and unmodified MIPs. RAM-MIPs were used as the adsorbent enclosed in solid phase extraction column and several important extraction parameters were comprehensively optimized to evaluate the extraction performance. Under the optimum extraction conditions, RAM-MIPs exhibited comparable or even higher selectivity with greater extraction capacity toward six kinds of organophosphorus pesticides (including malathion, ethoprophos, phorate, terbufos, dimethoate, and fenamiphos) compared with the MIPs and commercial solid phase extraction columns. The RAM-MIPs solid phase extraction coupled with gas chromatography was successfully applied to simultaneously determine six kinds of organophosphorus pesticides from honey sample. The new established method showed good linearity in the range of 0.01-1.0 μg mL(-1), low limits of detection (0.0005-0.0019 μg mL(-1)), acceptable reproducibility (RSD, 2.26-4.81%, n = 6), and satisfactory relative recoveries (90.9-97.6%). It was demonstrated that RAM-MIPs solid phase extraction with excellent selectivity and restricted access function was a simple, rapid, selective, and effective sample pretreatment method. PMID:25977034

  6. Extraction of organophosphorus pesticides by carbon-coated Fe3 O4 nanoparticles through response surface experimental design.

    PubMed

    Maddah, Bozorgmehr; Alidadi, Sattar; Hasanzadeh, Mahdi

    2016-01-01

    In this paper, carbon-coated Fe3 O4 nanoparticles were successfully synthesized and used as a magnetic solid-phase extraction absorbent for the preconcentration and extraction of organophosphorus pesticides in environmental water samples. The carbon-coated Fe3 O4 nanoparticles were characterized by transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The determination of organophosphorus pesticides in water samples with carbon-coated Fe3 O4 nanoparticles was investigated by high-performance liquid chromatography with a diode array detector. Furthermore, the response surface model based on the central composite design was applied to quantitatively investigate the effect of some important variables influencing the extraction efficiency, such as pH, treatment time, amount of nanoparticle sorbents, and amount of salt and to find the optimized conditions providing the highest extraction efficiency. Under optimized conditions, the calibration curve was linear in the range of 0.5-15.0 ng/mL with a regression coefficient of 0.9948, 0.9958, and 0.9931 for fenitrothion, diazinon, and ethion, respectively. The obtained results showed that this analytical method would be useful for the analysis of fenitrothion, diazinon, and ethion in tap water with high precision and accuracy. PMID:26519201

  7. Poly(ionic liquid) immobilized magnetic nanoparticles as new adsorbent for extraction and enrichment of organophosphorus pesticides from tea drinks.

    PubMed

    Zheng, Xiaoyan; He, Lijun; Duan, Yajing; Jiang, Xiuming; Xiang, Guoqiang; Zhao, Wenjie; Zhang, Shusheng

    2014-09-01

    New poly(ionic liquid) immobilized magnetic nanoparticles (PIL-MNPs) were synthesized via co-polymerization of 1-vinyl-3-hexylimidazolium-based ionic liquid and vinyl-modified magnetic particles and were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and magnetic measurements. The PIL-MNPs were utilized as adsorbent phases in magnetic solid-phase extraction (MSPE). The extraction and enrichment efficiency were evaluated by using four organophosphorus pesticides (parathion, fenthion, phoxim and temephos) as test analytes. Various parameters, such as amount of adsorbent, adsorption time, desorption solvent and time, and ionic strength were investigated. The proposed method showed good linearity for the analytes in the concentration range of 1-200μgL(-1) with a correlation coefficient (R)>0.9963. Low limit of detection of 0.01μgL(-1) and high enrichment factors ranging from 84 to 161 were achieved. The proposed method has been successfully used to determine organophosphorus pesticides from three tea drink samples with satisfactory recovery of 81.4-112.6% and RSDs of 4.5-11.3%. The PIL-MNP adsorbent can be reused for 20 times without a noticeable decrease in extraction efficiency. PMID:25022482

  8. DETOXIFICATION OF ORGANOPHOSPHATE PESTICIDES BY IMMOBILIZED ESCHERICHIA COLI EXPRESSING ORGANOPHOSPHORUS HYDROLASE ON CELL SURFACE. (R823663)

    EPA Science Inventory

    An improved whole-cell technology for detoxifying organophosphate nerve agents was recently developed based on genetically engineered Escherichia coli with organophosphorus hydrolase anchored on the surface. This article reports the immobilization of these novel biocatalys...

  9. Production and characterization of a broad-specificity polyclonal antibody for O,O-diethyl organophosphorus pesticides and a quantitative structure-activity relationship study of antibody recognition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polyclonal antibody (PAb) with broad-specificity for O,O-diethyl organophosphorus pesticides (OPs) against a generic hapten, 4-(diethoxyphosphoro thioyloxy) benzoic acid, was produced. The obtained PAb showed high sensitivity to seven commonly used O,O-diethyl OPs in a competitive indirect enzyme-l...

  10. Broad-specificity immunoassay for O,O-diethyl organophosphorus pesticides: Application of molecular modeling to improve assay sensitivity and study antibody recognition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A monoclonal antibody (MAb) against 4-(diethoxyphosphorothioyloxy)benzoic acid (hapten 1) was raised and used to develop a broad-specificity competitive indirect enzyme-linked immunosorbent assay (ciELISA) for 14 O,O-diethyl organophosphorus pesticides (OPs). Computer-assisted molecular modeling was...

  11. A simple, rapid, and high-throughput fluorescence polarization immunoassay for simultaneous detection of organophosphorus pesticides in vegetable and environmental water samples

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simple, rapid, and high-throughput fluorescent polarization immunoassay (FPIA) for simultaneous determination of organophosphorus pesticides (OPs) was developed. Three haptens were labeled with a fluorescein probe and used as tracers to develop a homogenous FPIA using a broad-specificity monoclon...

  12. A smartphone-readable barcode assay for the detection and quantitation of pesticide residues.

    PubMed

    Guo, Juan; Wong, Jessica X H; Cui, Caie; Li, Xiaochun; Yu, Hua-Zhong

    2015-08-21

    In this paper, we present a smartphone-readable barcode assay for the qualitative detection of methyl parathion residues, a toxic organophosphorus pesticide that is popularly used in agriculture worldwide. The detection principle is based on the irreversible inhibition of the enzymatic activity of acetylcholinesterase (AchE) by methyl parathion; AchE catalytically hydrolyzes acetylthiocholine iodine to thiocholine that in turn dissociates dithiobis-nitrobenzoate to produce a yellow product (deprotonated thio-nitrobenzoate). The yellow intensity of the product was confirmed to be inversely dependent on the concentration of the pesticide. We have designed a barcode-formatted assay chip by using a PDMS (polydimethylsiloxane) channel plate (as the reaction reservoir), situated under a printed partial barcode, to complete the whole barcode such that it can be directly read by a barcode scanning app installed on a smartphone. The app is able to qualitatively present the result of the pesticide test; the absence or a low concentration of methyl parathion results in the barcode reading as "-", identifying the test as negative for pesticides. Upon obtaining a positive result (the app reads a "+" character), the captured image can be further analyzed to quantitate the methyl parathion concentration in the sample. Besides the portability and simplicity, this mobile-app based colorimetric barcode assay compares favorably with the standard spectrophotometric method. PMID:26087169

  13. [Investigation of pesticide residues in foods distributed in Kitakyushu City].

    PubMed

    Ishikawa, Seiichi; Naetoko, Eri; Kawamura, Seiji; Yamaguchi, Rika; Higuchi, Masayuki; Kojima, Tsutomu; Yamato, Yasuhiro; Takahashi, Masaki

    2004-04-01

    We investigated 160 kinds of pesticide residues in 715 samples of 116 kinds of foods distributed in Kitakyushu city. Sixty kinds of pesticides were detected in 55 kinds of foods (204 samples) in the range of 0.002-22 mg/kg. Five kinds of pesticides in 7 samples violated the residue standards and the indication of "unused". The detection ratios of unregulated pesticide in domestic and imported foods were 27.8 and 33.0%, respectively. Iprodione, dicofol, diethofencarb, procymidone and chlorfenapyr (for domestic food) and total bromine, benomyl, chlorpyrifos, dicofol, fenvalerate, cypermethrin and dimethoate (for imported food) showed relatively high detection ratios. Chinese cabbage, garland chrysanthemum, tomatoes and green teas (domestic) and broccoli, bananas, grapefruit, lemons, oranges, frozen edamame and frozen kidney beans (imported) showed high relative pesticide detection ratios. Residual pesticides were detected with relatively high frequency in imported fruits, imported frozen foods and imported processed foods. PMID:15272606

  14. Distinct patterns of gene and protein expression elicited by organophosphorus pesticides in Caenorhabditis elegans

    PubMed Central

    Lewis, John A; Szilagyi, Maria; Gehman, Elizabeth; Dennis, William E; Jackson, David A

    2009-01-01

    Background The wide use of organophosphorus (OP) pesticides makes them an important public health concern. Persistent effects of exposure and the mechanism of neuronal degeneration are continuing issues in OP toxicology. To elucidate early steps in the mechanisms of OP toxicity, we studied alterations in global gene and protein expression in Caenorhabditis elegans exposed to OPs using microarrays and mass spectrometry. We tested two structurally distinct OPs (dichlorvos and fenamiphos) and employed a mechanistically different third neurotoxicant, mefloquine, as an out-group for analysis. Treatment levels used concentrations of chemical sufficient to prevent the development of 10%, 50% or 90% of mid-vulval L4 larvae into early gravid adults (EGA) at 24 h after exposure in a defined, bacteria-free medium. Results After 8 h of exposure, the expression of 87 genes responded specifically to OP treatment. The abundance of 34 proteins also changed in OP-exposed worms. Many of the genes and proteins affected by the OPs are expressed in neuronal and muscle tissues and are involved in lipid metabolism, cell adhesion, apoptosis/cell death, and detoxification. Twenty-two genes were differentially affected by the two OPs; a large proportion of these genes encode cytochrome P450s, UDP-glucuronosyl/UDP-glucosyltransferases, or P-glycoproteins. The abundance of transcripts and the proteins they encode were well correlated. Conclusion Exposure to OPs elicits a pattern of changes in gene expression in exposed worms distinct from that of the unrelated neurotoxicant, mefloquine. The functional roles and the tissue location of the genes and proteins whose expression is modulated in response to exposure is consistent with the known effects of OPs, including damage to muscle due to persistent hypercontraction, neuronal cell death, and phase I and phase II detoxification. Further, the two different OPs evoked distinguishable changes in gene expression; about half the differences are in

  15. Environmental exposure to organophosphorus and pyrethroid pesticides in South Australian preschool children: a cross sectional study.

    PubMed

    Babina, Kateryna; Dollard, Maureen; Pilotto, Louis; Edwards, John W

    2012-11-01

    Organophosphorus (OP) and pyrethroid (PYR) compounds are the most widely used insecticides. OPs and PYRs are developmental neurotoxicants. Understanding the extent of exposure in the general population and especially in young children is important for the development of public health policy on regulation and use of these chemicals. Presented here are the results of the first investigation into the extent of environmental exposure to neurotoxic insecticides in preschool children in South Australia (SA). Children were enrolled from different areas of SA and assigned into urban, periurban and rural groups according to their residential address. Residential proximity to agricultural activity, parental occupational contact to insecticides and use of insecticides within the household were investigated as potential indirect measures of exposure. We used liquid chromatography/tandem mass spectrometry to measure the following metabolites of OPs and PYRs in urine samples as direct indicators of exposure: dialkylphosphates, p-nitrophenol, 3-methyl-4-nitrophenol, 3,5,6-trichloro-2-pyridinol, cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid, cis-3-(2,2-dibromovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid, 2-methyl-3phenylbenzoic acid and 3-phenoxybenzoic acid. Results were analysed to assess factors affecting the risk and level of exposure. Results were also compared to the published data in similar age groups from US and German studies. The results of this study demonstrate that there was widespread chronic exposure to OPs and and PYRs in SA children. OP metabolites were detected more commonly than PYR. Exposure to more than one chemical and contemporaneous exposure to chemicals from both OP and PYR groups was common in the study population. There were some differences in risks and levels of exposure between the study groups. Exposure to some restricted use of chemicals, for example, fenitrothion, was higher in periurban and rural children

  16. Experimental strategy for translational studies of organophosphorus pesticide neurotoxicity based on real-world occupational exposures to chlorpyrifos

    PubMed Central

    Lein, Pamela J.; Bonner, Matthew R.; Farahat, Fayssal M.; Olson, James R.; Rohlman, Diane S.; Fenske, Richard A.; Lattal, K. Matthew; Lasarev, Michael R.; Galvin, Kit; Farahat, Taghreed M.; Anger, W. Kent

    2012-01-01

    Translational research is needed to understand and predict the neurotoxic consequences associated with repeated occupational exposures to organophosphorus pesticides (OPs). In this report, we describe a research strategy for identifying biomarkers of OP neurotoxicity, and we characterize pesticide application workers in Egypt’s Menoufia Governorate who serve as our anchor human population for developing a parallel animal model with similar exposures and behavioral deficits and for examining the influence of human polymorphisms in cytochrome P450 (CYP) and paraoxonase 1 (PON1) enzymes on OP metabolism and toxicity. This population has previously been shown to have high occupational exposures and to exhibit a broad range of neurobehavioral deficits. In addition to observational studies of work practices in the field, questionnaires on demographics, lifestyle and work practices were administered to 146 Egyptian pesticide application workers applying pesticides to the cotton crop. Survey results indicated that the application workforce uses standard operating procedures and standardized equipment provided by Egypt’s Ministry of Agriculture, which provides a workforce with a stable work history. We also found that few workers report using personal protective equipment (PPE), which likely contributes to the relatively high exposures reported in these application workers. In summary, this population provides a unique opportunity for identifying biomarkers of OP-induced neurotoxicity associated with occupational exposure. PMID:22240005

  17. One-step extraction for gas chromatography with flame photometric detection of 18 organophosphorus pesticides in Chinese medicine health wines.

    PubMed

    Liu, Qianzhen; Kong, Weijun; Qiu, Feng; Wei, Jianhe; Yang, Shihai; Zheng, Yuguo; Yang, Meihua

    2012-02-15

    An easy, rapid and selective gas chromatography with flame photometric detection (GC-FPD) method was established for simultaneously determining 18 organophosphorus pesticides (OPPs) in 80 Chinese medicine (CM) health wines. This method was based on a simple one-step extraction procedure using a little solvent without any further cleanup steps. The optimized extraction solvent for the pesticides is acetone:dichloromethane (1:1, V/V) with extraction recovery of 79.0-109.1% and relative standard deviation (RSD) of 0.36-12.68%, respectively. The limits of detection (LODs) of the established GC-FPD method for all investigated pesticides ranged from 1 to 15ngmL(-1) and limits of quantification (LOQs) from 4 to 50ngmL(-1). Out of all 80 CM health wines, 18 OPPs were found in 8 samples at low concentrations of 8.2-37.9ngmL(-1). These pesticides were successfully confirmed by GC-MS. This is the first report of determining OPPs in CM health wines, providing references for monitoring the quality of CM health wine in routine analysis. PMID:22285000

  18. Pesticides

    MedlinePlus

    ... are applied during farming and how much pesticide residue can remain in foods sold in stores. Exposure ... to pesticides at work should carefully clean any residue from their skin and remove their clothes and ...

  19. Fe3O4 magnetic nanoparticle peroxidase mimetic-based colorimetric assay for the rapid detection of organophosphorus pesticide and nerve agent.

    PubMed

    Liang, Minmin; Fan, Kelong; Pan, Yong; Jiang, Hui; Wang, Fei; Yang, Dongling; Lu, Di; Feng, Jing; Zhao, Jianjun; Yang, Liu; Yan, Xiyun

    2013-01-01

    Rapid and sensitive detection methods are in urgent demand for the screening of extensively used organophosphorus pesticides and highly toxic nerve agents for their neurotoxicity. In this study, we developed a novel Fe(3)O(4) magnetic nanoparticle (MNP) peroxidase mimetic-based colorimetric method for the rapid detection of organophosphorus pesticides and nerve agents. The detection assay is composed of MNPs, acetylcholinesterase (AChE), and choline oxidase (CHO). The enzymes AChE and CHO catalyze the formation of H(2)O(2) in the presence of acetylcholine, which then activates MNPs to catalyze the oxidation of colorimetric substrates to produce a color reaction. After incubation with the organophosphorus neurotoxins, the enzymatic activity of AChE was inhibited and produced less H(2)O(2), resulting in a decreased catalytic oxidation of colorimetric substrates over MNP peroxidase mimetics, accompanied by a drop in color intensity. Three organophosphorus compounds were tested on the assay: acephate and methyl-paraoxon as representative organophosphorus pesticides and the nerve agent Sarin. The novel assay displayed substantial color change after incubation in organophosphorus neurotoxins in a concentration-dependent manner. As low as 1 nM Sarin, 10 nM methyl-paraoxon, and 5 μM acephate are easily detected by the novel assay. In conclusion, by employing the peroxidase-mimicking activity of MNPs, the developed colorimetric assay has the potential of becoming a screening tool for the rapid and sensitive assessment of the neurotoxicity of an overwhelming number of organophosphate compounds. PMID:23153113

  20. [Occurrence of pesticide residues in raspberries in 2000-2005].

    PubMed

    Sadło, Stanisław; Szpyrka, Ewa; Rogozińska, Krystyna; Rupar, Julian; Kuźmenko, Arletta

    2007-01-01

    The aim of this paper was to present occurrence of pesticide residues in raspberries in 2000-2005. Gas chromatographic and spectroscopy methods were used. The most frequently found were tolylfluanid residues (43% of the analysed samples), procymidone residues (33%), pyrimethanil residues (15%), ethylenebisdithiocarbamates (EBDC) residues (8%) and iprodione residues (5%), while insecticides (mainly synthetic pyrethroids) cypermethrin residues (6%) and bifenthrin (4%). In 8 % of analysed samples EBDC residues exceeded the national Maximum Residue Level established for raspberries. On relatively the highest level EBDC occurred. PMID:18246655

  1. Levels of pesticides residues in the White Nile water in the Sudan.

    PubMed

    Nesser, Gibreel A A; Abdelbagi, Azhari O; Hammad, Ahmed Mohammed Ali; Tagelseed, Mirghani; Laing, Mark D

    2016-06-01

    Twenty-two commonly used pesticides were monitored during autumn, winter, and summer of 2004-2005 in 27 water samples from three sites along the White Nile in Sudan (former Sudan). Sites were selected to reflect pesticides gathered from drainage canals in central Sudan and from upstream sources. Collected samples were extracted and subjected to gas chromatographic analysis. Pesticides levels were measured in nanograms per liter. Pesticides residues were detected in 96 % of the samples with a total residue burden of 4132.6 ng L(-1), and an overall mean concentration and range of 50.99 and not detected-1570 ng L(-1), respectively. Ororganochlorines were the most frequently detected contaminants, which were found in 70 % of the samples, causing a total burden of 2852.8 ng L(-1), followed by pyrethroids 15 % of the samples, with a total burden of 926.5 ng L(-1). The tested herbicides were detected in ˂4 % of the samples with a total burden of 353.3 ng L(-1), while organophosphorus levels were below the detection limit. The most frequent contaminants were the following: heptachlor and its epoxide (52 % of samples), followed by DDTs (dichlorodiphenyltrichloroethanes) (DDT and DDE, in 19 % of the samples), cypermethrin and fenvalerate (in 11 % of the samples), and pendimethalin (in <4 % of the samples). Residues of hexachlorocyclohexane (HCH) isomers (α, β, γ and δ), endosulfan (α and β), p, p-DDD, λ cyhalothrin, deltamethrin, and oxyfluorfen were not detected in the analyzed samples. Generally, levels were least in autumn, and followed by summer and winter. Sources of contamination might include agricultural lands in central Sudan and upstream sources. Both recent and old contaminations were indicated. PMID:27230426

  2. FOR HEALTHY KIDS: REDUCTION OF HOME PESTICIDE RESIDUE EXPOSURES

    EPA Science Inventory

    For Healthy Kids focuses on preventing children's exposure to pesticides by educating agricultural workers on preventing "the take home pathway" for pesticide residue. A baseline survey encompassing over 570 households in the Yakima valley was conducted in the summer of 1999. Ho...

  3. Laundering as decontamination of apparel fabrics: residues of pesticides from six chemical classes.

    PubMed

    Nelson, C; Laughlin, J; Kim, C; Rigakis, K; Raheel, M; Scholten, L

    1992-07-01

    Research on reducing the level of pesticide residue on a textile substrate has examined many variables under many different conditions. This study controlled fiber type and the use of prewash product in an examination of residue levels for a number of pesticides in different pesticide classes. For all pesticides examined, the use of prewash lowered pesticide residues regardless of fiber type. Differences in pesticide residue level attributable to fiber type were not consistent. PMID:1637202

  4. Application of Box-Behnken design for the removal of two organophosphorus pesticides by used Tea leaves

    NASA Astrophysics Data System (ADS)

    Albanis, Triantafyllos; Valileios, Sakkas; Islam, Azharul M.

    2016-04-01

    Removal of two organophosphorus pesticides bromophos methyl [BM: O, O- dimethyl - O - (2, 5-dichloro -4 bromophenyl) phosphorothioate] and quinalphos [QP: O, O-diethyl O-2-quinoxalinyl phosphorothioate] on used tea leaves were studied by batch equilibration method. Adsorption isotherms were conformed well to Langmuir for quinalphos and Freundlich equation for bromophos methyl. The kinetic data fitted well by the pseudo second order model for both pesticides. Box-Behnken design was successfully employed for experimental design and analysis of results. The interactions of pH, initial concentration and adsorbent dose on two pesticides adsorption by used tea leaves were investigated by this model. The optimum pH, initial concentration and adsorbent dose with their corresponding removal efficiency were found to be 7.88, 11.94 mg L-1, 0.37g and 100% for bromophos methyl respectively, for quinalphos 8.72, 6.44 mg L-1, 0.39g and 93.98% respectively. Keywords: Box-Behnken; quinalphos; bromophos methyl; Kinetics; used tea leaves

  5. In vivo tracing of organochloride and organophosphorus pesticides in different organs of hydroponically grown malabar spinach (Basella alba L.).

    PubMed

    Qiu, Junlang; Chen, Guosheng; Xu, Jianqiao; Luo, Erlun; Liu, Yan; Wang, Fuxin; Zhou, Hong; Liu, Yuan; Zhu, Fang; Ouyang, Gangfeng

    2016-10-01

    An in vivo uptake and elimination tracing study based on solid phase microextraction (SPME) was conducted to investigate the accumulation, persistence and distribution of organochloride pesticides (OCPs) and organophosphorus pesticides (OPPs) in malabar spinach (Basella alba L.) plants. Uptake and elimination of the pesticides were traced in leaves, stems and roots of living malabar spinach plants. Root concentration factor (RCF), distribution concentration factor (DCF) and transpiration stream concentration factor (TSCF) were calculated based on the in vivo tracing data. The tracing data showed that the OCPs were much more accumulative and persistent than the OPPs in roots, while they were similarly accumulative and persistent in leaves and stems. RCF values of the OPPs or OCPs were likely to increase with the increase in LogKow values except fenthion. Obtained DCF values indicated that OPPs and OCPs were more accumulative in the organs containing more lipids. TSCF values showed that the translocation of OPPs and OCPs from roots to foliage was firstly dependent on the hydrophobicity of the compounds, but also significantly affected by the water solubility. This is the first study of generating RCF, DCF and TSCF data in living plants by in vivo sampling method, which provides a foundation to promote the application of in vivo SPME and improve understanding of contaminant behaviors in living plants. PMID:27209519

  6. The 47th annual Florida pesticide residue workshop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is an introductory article to a special section of the Journal of Agricultural and Food Chemistry consisting of publications from the 47th Annual Florida Pesticide Residue Workshop held in St. Pete Beach, FL in July of 2010....

  7. Organochlorine pesticides residue in breast milk: a systematic review

    PubMed Central

    Pirsaheb, Meghdad; Limoee, Mojtaba; Namdari, Farideh; Khamutian, Razieh

    2015-01-01

    Background: Chlorinated pesticides have been used in pest control for several decades in the world. These compounds are still applied in many regions, and their continuous usage has resulted in their bioaccumulation and residue in the food chain. These residues could transfer to food products and accumulate in fat tissues. Undoubtedly, the breast milk could be a significant biomarker for estimation of these residues in the human body. This study was conducted to review and compile the results of the studies undertaken in the world which surveyed the organochlorine pesticides residue in breast milk. Methods: A total of 710 national and international articles and texts related to the focused subject were extracted from the virtual databases using the following key words: Chlorinated pesticides, residue and breast milk. Thirty articles published between 1980 and 2013 were selected and reviewed. Results: The majority of the reviewed articles indicated the presence of two or more organochlorine pesticides in the collected samples of breast milk. Based on the reviewed studies, dichlorodiphenyltrichloroethane (DDT) had the highest level of concentration in the collected samples of breast milk. Moreover, there was a statistically significant positive correlation between mother’s age, her multiparty and concentration of chlorinated pesticides in breast milk. Conclusion: The organochlorine pesticides are still applied in some developing countries including some regions of Iran. Thus, it seems essential to inform the community about the adverse effects of this class of pesticides; and most importantly the governments should also ban the use of such compounds. PMID:26478886

  8. Pesticide residue quantification analysis by hyperspectral imaging sensors

    NASA Astrophysics Data System (ADS)

    Liao, Yuan-Hsun; Lo, Wei-Sheng; Guo, Horng-Yuh; Kao, Ching-Hua; Chou, Tau-Meu; Chen, Junne-Jih; Wen, Chia-Hsien; Lin, Chinsu; Chen, Hsian-Min; Ouyang, Yen-Chieh; Wu, Chao-Cheng; Chen, Shih-Yu; Chang, Chein-I.

    2015-05-01

    Pesticide residue detection in agriculture crops is a challenging issue and is even more difficult to quantify pesticide residue resident in agriculture produces and fruits. This paper conducts a series of base-line experiments which are particularly designed for three specific pesticides commonly used in Taiwan. The materials used for experiments are single leaves of vegetable produces which are being contaminated by various amount of concentration of pesticides. Two sensors are used to collected data. One is Fourier Transform Infrared (FTIR) spectroscopy. The other is a hyperspectral sensor, called Geophysical and Environmental Research (GER) 2600 spectroradiometer which is a batteryoperated field portable spectroradiometer with full real-time data acquisition from 350 nm to 2500 nm. In order to quantify data with different levels of pesticide residue concentration, several measures for spectral discrimination are developed. Mores specifically, new measures for calculating relative power between two sensors are particularly designed to be able to evaluate effectiveness of each of sensors in quantifying the used pesticide residues. The experimental results show that the GER is a better sensor than FTIR in the sense of pesticide residue quantification.

  9. Pesticide residues in rain water from Hisar, India.

    PubMed

    Kumari, Beena; Madan, V K; Kathpal, T S

    2007-10-01

    Presence of pesticide residues was studied in rain water during 2002 employing multi residue analysis method by gas liquid chromatography equipped with ECD and NPD detectors and capillary columns. The presence of pesticide residues in surface aquatic system triggered the investigation of the presence of pesticides in rain water. A total of 13 pesticides were detected in rain water samples. Among the different groups of pesticides, organochlorines were present in the range of 0.041-7.060 ppb with maximum concentration of p,p'-DDT up to 7.060 microg l(-1). Synthetic pyrethroids were present ranging from 0.100 to 1.000 microg l(-1) and organophosphates in the range of 0.050-4.000 microg l(-1) showing maximum contamination with cypermethrin (1.000 microg l(-1)) and monocrotophos (4.000 microg l(-1)) of the respective groups. Almost 80% samples showed the residues above MRL of 0.5 ppb fixed for multi residues and on the basis of single pesticide, 16-50% samples contained residues above the MRL value of 0.1 ppb. PMID:17268917

  10. Organochlorine pesticide residues in wheat from Konya region, Turkey.

    PubMed

    Guler, G O; Cakmak, Y S; Dagli, Z; Aktumsek, A; Ozparlak, H

    2010-05-01

    The present study has been carried out to evaluate the organochlorine pesticide contamination in wheat from Konya region. This region is the largest area of cereal production in Turkey. The contamination level has been determined according to the European Community Directives. Different wheat samples (36) were obtained from local farmers and wheat factories in this region. All the wheat samples examined were found to be contaminated by organochlorine pesticide residues of cis-Chlordane and methoxychlor. Chlordane isomers, methoxychlor, DDT and its metabolites, aldrin, beta HCH, heptachlor and lindane have been found to be the highest organochlorine pesticide residues. In some of these samples, various organochlorine pesticide residues have been determined to be higher than European Community maximum residual limits. The residues of aldrin in one sample, trans-Chlordane in one sample, oxy-chlordane in eight samples and methoxychlor in one sample were found to be in excess of EC MRLs. Since most of the samples have been found to be contaminated with residues and some residues exceed EC MRLs, a control of organochlorine pesticide residues in wheat is necessary. PMID:20156519

  11. 78 FR 70906 - Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... AGENCY 40 CFR Part 180 Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on... residues of pesticide chemicals in or on various commodities. DATES: Comments must be received on or before...), requesting the establishment or modification of regulations in 40 CFR part 180 for residues of...

  12. EXPOSURE TO CHILDREN FROM PESTICIDE RESIDUES

    EPA Science Inventory

    Children's aggregate exposure to pesticides will be characterized using pesticide exposure data from Brownsville, TX. The aggregate exposure methodology developed in this phase of the project will be tested with a larger data set from Arizona using data from US-Mexico border are...

  13. [Pesticide residual status in litchi orchard soils in Guangdong, China].

    PubMed

    Yao, Li-Xian; Huang, Lian-Xi; Li, Guo-Liang; He, Zhao-Huan; Zhou, Chang-Min; Yang, Bao-Mei; Guo, Bin

    2010-11-01

    Litchi is a famous tropical and subtropical fruit originated in South China. Guangdong is one of the most important litchi production areas in China. Two hundred and eight soil samples were collected in litchi orchards after harvesting the fruit, in which nine often-used pesticides including metalaxyl, mancozeb, carbendazim, deltamethrin, cypermethrin, cyhalothrin, dipterex, dimethoate and dichlorvos were detected. The results showed that the detectable rates of various pesticides were ranked cypermethrin (59.1%) > carbendazim (51.0%) > mancozeb (11.1%) > metalaxyl (6.7%) > cyhalothrin (3.4%). Dimethoate and dichlorvos were detectable in few soil samples, and deltamethrin and dipterex were undetectable in all samples. The percentages of soil samples where different pesticides could be detected in one sample followed the order: one pesticide detectable (40.4%) > two pesticides simultaneously detectable (31.3%) > pesticide undetectable (18.8%) > three pesticides simultaneously detectable (8.2%) > four pesticides simultaneously detectable (1.4%). The concentrations of mancozeb in detectable samples averaged 39.05 microg x kg(-1), and that of cypermethrin was 7.83 microg x kg(-1). The mean concentrations of the other five pesticides ranged from 0.19 microg x kg(-1) to 1.65 microg x kg(-1). Totally, the pesticide residue status in litchi orchards in Guangdong was venial. PMID:21250457

  14. Application of magnetic solvent bar liquid-phase microextraction for determination of organophosphorus pesticides in fruit juice samples by gas chromatography mass spectrometry.

    PubMed

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

    2015-06-01

    A simple, rapid and sensitive sample pretreatment technique, magnetic solvent bar liquid-phase microextraction (MSB-LPME) was developed for extracting organophosphorus pesticides from fruit juice. The analytes were extracted from the sample to the organic solvent immobilized in the fiber. The magnetic solvent bar not only can be used to stir the samples but also extract the analytes. After extraction, the analyte-adsorbed magnetic solvent bar can be readily isolated from the sample solution by a magnet, which could greatly simplify the operation and reduce the whole pretreatment time. The bar was eluted with methanol. The elute was evaporated to dryness and residue was dissolved in hexane. Several experimental parameters were investigated and optimized, including type of extraction solvent, number of magnetic solvent bar, extraction temperature, extraction time, salt concentration, stirring speed, pH and desorption conditions. The recoveries were in the range of 81.3-104.6%, and good reproducibilities were obtained with relative standard deviation below 6.1%. PMID:25624224

  15. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  16. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  17. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  18. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  19. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  20. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  1. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  2. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  3. 40 CFR 158.2172 - Experimental use permit microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2172 Experimental use permit microbial pesticides residue data requirements table. (a)...

  4. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Microbial pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Microbial Pesticides § 158.2130 Microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  5. Airborne pesticide residues along the Mississippi River

    USGS Publications Warehouse

    Majewski, M.S.; Foreman, W.T.; Goolsbys, D.A.; Nakagaki, N.

    1998-01-01

    The occurrence, concentration, and geographical distribution of agricultural pesticides were determined in air over the Mississippi River from New Orleans, LA, to St. Paul, MN, during the first 10 days of June 1994. Air samples were collected from a research vessel by pulling air through polyurethane foam plugs at about 100 L/min for up to 24 h. Each sample was analyzed for 42 pesticides and 3 pesticide transformation products. Twenty- five compounds-15 herbicides, 7 insecticides, and 3 pesticide transformation products-were detected in one or more samples with concentrations ranging from 0.05 to 80 ng/m3. Alachlor, chlorpyrifos, diazinon, fonofos, malathion, methyl parathion, metolachlor, metribuzin, pendimethalin, and trifluralin were detected in 80% or more of the samples. The highest concentrations for chlorpyrifos (1.6 ng/m3), diazinon (0.36 ng/m3), and malathion (4.6 ng/m3) all occurred near major metropolitan areas. These samples represent a 'snapshot in time', a spatial and temporal integration of which pesticides were present in the air during each sampling period. The occurrence and atmospheric concentrations of the observed pesticides were most closely related to their use on cropland within 40 km of the river.The occurrence, concentration, and geographical distribution of agricultural pesticides were determined in air over the Mississippi River from New Orleans, LA, to St. Paul, MN, during the first 10 days of June 1994. Air samples were collected from a research vessel by pulling air through polyurethane foam plugs at about 100 L/min for up to 24 h. Each sample was analyzed for 42 pesticides and 3 pesticide transformation products. Twenty-five compounds-15 herbicides, 7 insecticides, and 3 pesticide transformation products-were detected in one or more samples with concentrations ranging from 0.05 to 80 ng/m3. Alachlor, chlorpyrifos, diazinon, fonofos, malathion, methyl parathion, metolachlor, metribuzin, pendimethalin, and trifluralin were detected in

  6. Assessment of pesticide residues in two arable soils from the semi-arid and subtropical regions of China.

    PubMed

    Wang, Ligang; Zhao, Zhenhua; Jiang, Xin; Wu, Jinshui; Martens, Dieter

    2005-10-01

    The residues of 31 chlorinated hydrocarbons (CHCs), 25 chlorophenols (CPs), 30 organophosphorus (OP) and pyrethroid (PRT) in two arable soils from the semi-arid and subtropical regions of China were assessed. Data obtained indicate that the main compounds of CHC pesticide residues in the semi-arid soil were 4,4'-DDE (25.3 ng/g) and beta-HCH (14.1 ng/g), which totally accounted to about 90% of total CHC residues detected. The total content of CHC residues detected in the subtropical soil was only 3.1 ng/g, of which approximately 50% was beta-HCH. However, the total content of CP residues in both of the soils was about 11 ng/g. In the semi-arid soil, only parathion-methyl amongst the 30 compounds of OP and PRT residues was detected (32.5 ng/g), whilst malathion and parathion-methyl (8.7 and 17.7 ng/g, respectively) detected in the subtropical soil. Based on these results, it was suggested the environmental risk of pesticide residues ranked in an order as CHCs (mainly as 4,4'-DDE, beta-HCH) > OP (parathion-methyl) > CPs for the semi-arid soil, and as OPs (parathion-methyl and malathion) > CPs > CHCs (beta-HCH) for the subtropical soil. PMID:16240205

  7. Matrix solid-phase dispersion extraction of organophosphorus pesticide using SiO2-poly(N-vinylimidazole)

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Solís, M. C.; Muñoz-Rodríguez, D.; Medina-Peralta, S.; Carrera-Figueiras, C.; Ávila-Ortega, A.

    2013-06-01

    A sorbent material based on silica particles modified with poly(N-vinylimidazole) (SiO2-PVI) has been evaluated for the treatment of samples by matrix solid-phase dispersion (MSPD). The extraction of four organophosphorus pesticides was done from a spiked tomato and the extracts were analyzed by gas chromatography coupled to mass spectrometry. Six elution solvents were evaluated and acetone was selected due to better recovery of the four pesticides and low background signal in the chromatograms. A factorial design 24 was used for selection of extraction conditions. The factors were contact time, acetone volume, treatment (with or without freeze-drying) and adsorbent (SiO2 or SiO2-PVI). The best recoveries were obtained using 15 minutes of contact, 2 mL of solvent and sorbent without freeze-drying. The recoveries were between 60 and 83% for SiO2-PVI in spiked tomato with 0.2 and 0.8μg/g.

  8. A review of organochlorine pesticide residues in ferruginous hawk eggs

    USGS Publications Warehouse

    Henny, C.J.

    1985-01-01

    Ten Ferruginous Hawk nests in northeast Oregon were studied from 1978 to 1980. Pesticide residues, eggshell thickness, and reproductive success from these nests will be reviewed. In addition, egg residues from other published studies in the Pacific Northwest and elsewhere will be discussed.

  9. Pesticides

    MedlinePlus

    ... and rats. Because of the widespread use of agricultural chemicals in food production, people are exposed to ... effects of these pesticide residues. Results from the Agricultural Health Study, an ongoing study of pesticide exposures ...

  10. NEUROTOXICOLOGICAL AND STATISTICAL ANALYSES OF A MIXTURE OF FIVE ORGANOPHOSPHORUS PESTICIDES USING A RAY DESIGN.

    EPA Science Inventory

    Pesticide application patterns generally result in exposure to mixtures instead of single chemicals. Of particular importance in the estimation of pesticide mixture risks is the detection and characterization of their interactions. This research tested for interaction(s) in a mix...

  11. NON-ADDITIVE INTERACTIONS OF AN ORGANOPHOSPHORUS PESTICIDE MIXTURE IN ADULT AND PREWEANLING RATS.

    EPA Science Inventory

    Critical features of risk assessment include the evaluation of risk following exposure to pesticide mixtures as well as the potential for increased sensitivity of the young. The US EPA is required to regulate pesticides acting via a common mechanism of action as a group, e.g.,...

  12. Recovery of cholinesterase activity in five avian species exposed to dicrotophos, an organophosphorus pesticide

    USGS Publications Warehouse

    Fleming, W.J.; Grue, C.E.

    1981-01-01

    The responses of brain and plasma cholinesterase (ChE) activities were examined in mallard ducks, bobwhite quail, barn owls, starlings, and common grackles given oral doses of dicrotophos, an organophosphorus insecticide. Up to an eightfold difference in response of brain ChE activity to dicrotophos was found among these species. Brain ChE activity recovered to within 2 SD of normal within 26 days after being depressed 55 to 64%. Recovery of brain ChE activity was similar among species and followed the model Y = a + b (log10X).

  13. Glove accumulation of pesticide residues for strawberry harvester exposure assessment.

    PubMed

    Li, Yanhong; Chen, Li; Chen, Zhenshan; Coehlo, Joe; Cui, Li; Liu, Yu; Lopez, Terry; Sankaran, Gayatri; Vega, Helen; Krieger, Robert

    2011-06-01

    We investigated the accumulation of pesticide residues on rubber latex gloves that are used by strawberry harvesters to protect their skin, reduce pesticide exposure and promote food safety. Gloves accumulated residues of 16 active ingredients including azoxystrobin, bifenthrin, boscalid, captan, cyprodinil, fenhexamid, fenpropathrin, fludioxonil, hexythiazox, malathion, methomyl, naled, propiconazole, pyraclostrobin, quinoline, and quinoxyfen at different times. Glove residue accumulation (t(½) 2.8-3.7 d) was very similar to the dissipation of DFRs (t(½) 2.1-3.0 d) during the first 3 weeks after malathion applications. Dermal malathion dose was 0.2 mg/kg at the preharvest interval and declined to trace levels during the following 3 months. Glove accumulation of malathion indicated trace surface residue availability and was used to assess the relationship between dislodgable foliar residues and potential hand exposure. PMID:21503692

  14. Dual-layer solid-phase extraction based on molecular imprinting technology: Seeking a route to enhance selectivity for trace analysis of pesticide residues in olive oil.

    PubMed

    Garcia, Raquel; Carreiro, Elisabete P; Nunes, José; da Silva, Marco Gomes; Freitas, Ana Maria Costa; Burke, Anthony J; Cabrita, Maria João

    2016-07-01

    Aiming to introduce a multiresidue analysis for the trace detection of pesticide residues belonging to organophosphorus and triazine classes from olive oil samples, a new sample preparation methodology comprising the use of a dual layer of "tailor-made" molecularly imprinted polymers (MIPs) SPE for the simultaneous extraction of both pesticides in a single procedure has been attempted. This work has focused on the implementation of a dual MIP-layer SPE procedure (DL-MISPE) encompassing the use of two MIP layers as specific sorbents. In order to achieve higher recovery rates, the amount of MIP layers has been optimized as well as the influence of MIP packaging order. The optimized DL-MISPE approach has been used in the preconcentration of spiked organic olive oil samples with concentrations of dimethoate and terbuthylazine similar to the maximum residue limits and further quantification by HPLC. High recovery rates for dimethoate (95%) and terbuthylazine (94%) have been achieved with good accuracy and precision. Overall, this work constitutes the first attempt on the development of a dual pesticide residue methodology for the trace analysis of pesticide residues based on molecular imprinting technology. Thus, DL-MISPE constitutes a reliable, robust, and sensitive sample preparation methodology that enables preconcentration of the target pesticides in complex olive oil samples, even at levels similar to the maximum residue limits enforced by the legislation. PMID:27062483

  15. Global Harmonization of Maximum Residue Limits for Pesticides.

    PubMed

    Ambrus, Árpád; Yang, Yong Zhen

    2016-01-13

    International trade plays an important role in national economics. The Codex Alimentarius Commission develops harmonized international food standards, guidelines, and codes of practice to protect the health of consumers and to ensure fair practices in the food trade. The Codex maximum residue limits (MRLs) elaborated by the Codex Committee on Pesticide Residues are based on the recommendations of the FAO/WHO Joint Meeting on Pesticides (JMPR). The basic principles applied currently by the JMPR for the evaluation of experimental data and related information are described together with some of the areas in which further developments are needed. PMID:25603277

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

    EPA Science Inventory

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

  17. 78 FR 33785 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-05

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  18. 75 FR 65321 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    ...This notice announces the Agency's receipt of several initial filings of pesticide petitions proposing the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  19. 77 FR 25954 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-02

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  20. 78 FR 56185 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-12

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  1. 78 FR 11126 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  2. 76 FR 61647 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-05

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  3. 77 FR 43562 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  4. 76 FR 39358 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-06

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  5. 76 FR 82238 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  6. 76 FR 49396 - Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ...This document announces the Agency's receipt of an initial filing of a pesticide petition requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  7. 77 FR 59578 - Notice of Filing of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  8. 76 FR 53372 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-26

    ...This document announces the Agency's receipt of several initial filings of pesticide petitions requesting the establishment or modification of regulations for residues of pesticide chemicals in or on various...

  9. Sampling and sample processing in pesticide residue analysis.

    PubMed

    Lehotay, Steven J; Cook, Jo Marie

    2015-05-13

    Proper sampling and sample processing in pesticide residue analysis of food and soil have always been essential to obtain accurate results, but the subject is becoming a greater concern as approximately 100 mg test portions are being analyzed with automated high-throughput analytical methods by agrochemical industry and contract laboratories. As global food trade and the importance of monitoring increase, the food industry and regulatory laboratories are also considering miniaturized high-throughput methods. In conjunction with a summary of the symposium "Residues in Food and Feed - Going from Macro to Micro: The Future of Sample Processing in Residue Analytical Methods" held at the 13th IUPAC International Congress of Pesticide Chemistry, this is an opportune time to review sampling theory and sample processing for pesticide residue analysis. If collected samples and test portions do not adequately represent the actual lot from which they came and provide meaningful results, then all costs, time, and efforts involved in implementing programs using sophisticated analytical instruments and techniques are wasted and can actually yield misleading results. This paper is designed to briefly review the often-neglected but crucial topic of sample collection and processing and put the issue into perspective for the future of pesticide residue analysis. It also emphasizes that analysts should demonstrate the validity of their sample processing approaches for the analytes/matrices of interest and encourages further studies on sampling and sample mass reduction to produce a test portion. PMID:25677085

  10. Pesticide residues in agricultural drains, southeastern desert area, California

    USGS Publications Warehouse

    Eccles, Lawrence A.

    1979-01-01

    A study is being made to determine the occurrence and distribution of pesticides in the agricultural drains for approximately 3/4 million irrigated acres in the southeastern desert area of California. This report describes the results of the first year of sampling and analyzing (1) water in the drains , (2) bed material in the drains, (3) water from field tile-drainage lines, and (4) irrigation tailwater and water in the drains directly exposed to drift from aerial application of pesticides. Residues of almost all the pesticides selected for monitoring were found in water in the drains. Examination of the data to determine the probable source of pesticides indicated generally slight concentrations from bed material in the drains, usually no detectable concentrations from field tile-drainage lines, and apparently large concentrations from irrigation tailwater and drift from aerial application. (Woodard-USGS)

  11. Sorption and degradation of chlorophenols, nitrophenols and organophosphorus pesticides in the subsoil under landfills — laboratory studies

    NASA Astrophysics Data System (ADS)

    Kjeldsen, Peter; Kjølholt, Jesper; Schultz, Birgit; Christensen, Thomas H.; Tjell, Jens Christian

    1990-09-01

    Landfills and old industrial plant sites have been identified in an increasing number of cases as point sources of groundwater pollution, dissipating a wide range of industrial chemicals and pesticides. To study the fate of co-disposed chemicals in the subsoil of landfills, anaerobic soil columns loaded with anaerobic leachate from a municipal landfill were set up. The leachate was spiked with eleven compounds representing three groups of chemicals: chlorophenols, nitrophenols and organophosphates. Two subsoils were used in the study. The columns were maintained at Danish groundwater temperature (8-10°C), and were run for a period of 10 months. Analysis of the influent leachate concentrations of the spiked compounds showed that the concentrations were constant during the entire experimental period. Many of the compounds showed delayed breakthrough (compared to chloride breakthrough) in both soils, followed by a constant effluent concentration ratio of less than unity indicating that degradation was occuring. The velocities for the chloro- and nitrophenols were in the range of 10-100% of the water velocity in the two subsoils. The distribution coefficient for the specific phenol, the acidity and the pH of the soil apparently governed the retardation of the phenolic compounds. Degradation of most of the phenols was observed with half-like values of 30-150 days. The four organophosphorus pesticides, Dimethoate ®, Malathion ®, Sulfotep ® and Fenitrothion ®, showed relative velocities from < 10% to ≈ 100%. Malathion ® and Sulfotep ® were degraded with half-life values of 10-20 days, while Dimethoate ® was not significantly degraded in the two soil columns. Fenitrothion ® did not appear in the effluent from the columns within the experimental period of time, probably due to high retardation.

  12. Tolerance of ARPE 19 cells to organophosphorus pesticide chlorpyrifos is limited to concentration and time of exposure.

    PubMed

    Gomathy, Narayanan; Sumantran, Venil N; Shabna, A; Sulochana, K N

    2015-01-01

    Age related macular degeneration is a blinding disease common in elder adults. The prevalence of age related macular degeneration has been found to be 1.8% in the Indian population. Organophosphates are widely used insecticides with well documented neurological effects, and the persistent nature of these compounds in the body results in long term health effects. Farmers exposed to organophosphorus pesticides in USA had an earlier onset of age related macular degeneration when compared to unexposed controls. A recent study found significant levels of an organophosphate, termed chlorpyrifos, in the blood samples of Indian farmers. Therefore, in understanding the link between age related macular degeneration and chlorpyrifos, the need for investigation is important. Our data show that ARPE-19 (retinal pigment epithelial cells) exhibit a cytoprotective response to chlorpyrifos as measured by viability, mitochondrial membrane potential, superoxide dismutase activity, and increased levels of glutathione peroxidase and reduced glutathione, after 24 h exposure to chlorpyrifos. However, this cytoprotective response was absent in ARPE-19 cells exposed to the same range of concentrations of chlorpyrifos for 48 h. These results have physiological significance, since HPLC analysis showed that effects of chlorpyrifos were mediated through its entry into ARPE-19 cells. HPLC analysis also showed that chlorpyrifos remained stable, as we recovered up to 80% of the chlorpyrifos added to 6 different ocular tissues. PMID:25619908

  13. Prenatal Exposure of Guinea Pigs to the Organophosphorus Pesticide Chlorpyrifos Disrupts the Structural and Functional Integrity of the Brain

    PubMed Central

    Mullins, Roger J.; Xu, Su; Pereira, Edna F.R.; Pescrille, Joseph D.; Todd, Spencer W.; Mamczarz, Jacek; Albuquerque, Edson X.; Gullapalli, Rao P.

    2015-01-01

    This study was designed to test the hypothesis that prenatal exposure of guinea pigs to the organophosphorus (OP) pesticide chlorpyrifos (CPF) disrupts the structural and functional integrity of the brain. Pregnant guinea pigs were injected with chlorpyrifos (20 mg/kg, s.c.) or vehicle (peanut oil) once per day for ten consecutive days, starting approximately on the 50th day of gestation. Cognitive behavior of female offspring was examined starting at 40–45 post-natal days (PND) using the Morris Water Maze (MWM), and brain structural integrity was analyzed at PND 70 using magnetic resonance imaging (MRI) methods, including T2-weighted anatomical scans and Diffusion Kurtosis Imaging (DKI). The offspring of exposed mothers had significantly decreased body weight and brain volume, particularly in the frontal regions of the brain including the striatum. Furthermore, the offspring demonstrated significant spatial learning deficits in MWM recall compared to the vehicle group. Diffusion measures revealed reduced white matter integrity within the striatum and amygdala that correlated with spatial learning performance. These findings reveal the lasting effect of pre-natal exposure to CPF as well as the danger of mother to child transmission of CPF in the environment. PMID:25704171

  14. Highly-sensitive organophosphorus pesticide biosensors based on CdTe quantum dots and bi-enzyme immobilized eggshell membranes.

    PubMed

    Xue, Gao; Yue, Zhao; Bing, Zhang; Yiwei, Tang; Xiuying, Liu; Jianrong, Li

    2016-02-01

    An optical biosensing method using CdTe quantum dots (QDs) and bi-enzyme-immobilized eggshell membranes for the determination of organophosphorus pesticides (OPs) has been developed. Increasing amounts of OPs led to a decrease of the enzymatic activity and thus a decrease in the production of hydrogen peroxide (H2O2), which can quench the fluorescence of the CdTe QDs. Under the optimum conditions, there was a good linear relationship between the enzyme inhibition percentage and the logarithm of paraoxon or parathion concentration in the range of 1.0 × 10(-11)-1.0 × 10(-6) mol L(-1). The detection limit (S/N = 3) of the proposed biosensors were as low as 4.30 × 10(-12) mol L(-1) for paraoxon and 2.47 × 10(-12) mol L(-1) for parathion. The bi-enzyme-immobilized eggshell membrane demonstrated a long shelf-life of at least 2 months and the results showed good repeatability. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results. PMID:26688862

  15. Enhanced degradation of five organophosphorus pesticides in skimmed milk by lactic acid bacteria and its potential relationship with phosphatase production.

    PubMed

    Zhang, Ying-Hua; Xu, Di; Liu, Jia-Qi; Zhao, Xin-Huai

    2014-12-01

    Skimmed milk spiked with five organophosphorus pesticides (OPPs), chlorpyrifos, diazinon, fenitrothion, malathion and methyl parathion, was fermented by ten lactic acid bacteria (LAB) and four strain combinations at 42°C for 24h. OPPs left in the samples at different times were extracted, purified, detected by gas chromatography and calculated for degradation rate constants, based on a first-order reaction model. OPPs degradation was enhanced by the inoculated LAB, resulting in 0.8-225.4% increase in the rate constants. Diazinon and methyl parathion were more stable whereas chlorpyrifos, fenitrothion and malathion were more labile. Lactobacillus brevis 1.0209 showed the strongest acceleration on OPPs degradation while strain combination could bring about a synergy between the strains of lower ability. Phosphatase production of the strains might be one of the key factors responsible for the enhanced OPPs degradation, as the detected phosphatase activities were positively correlated to the measured degradation rate constants of OPPs (r=0.636-0.970, P<0.05). PMID:24996321

  16. In-capillary derivatization and laser-induced fluorescence detection for the analysis of organophosphorus pesticides by micellar electrokinetic chromatography.

    PubMed

    Zhou, Lei; Luo, Zhi; Wang, Shumin; Hui, Yang; Hu, Zhide; Chen, Xingguo

    2007-05-18

    We developed a rapid and sensitive method using in-capillary derivatization and laser-induced fluorescence (LIF) detection for the fully automated analysis of organophosphorus pesticides (OPPs), including glufosinate, aminomethylphosphonic acid (AMPA) and glyphosate by micellar electrokinetic chromatography (MEKC). The potential of 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as in-capillary derivatization reagent is described for the first time. The unique feature of this MEKC method is the capillary being used as a small reaction chamber. In in-capillary derivatization, the sample and reagent solutions were injected directly into the capillary by tandem mode, followed by an electrokinetic step to enhance the mixing efficiency of analytes and reagent plugs in accordance with their different electrophoretic mobilities. Standing a specified time for reaction, the derivatives were then immediately separated and determined. Careful optimization of the derivatization and separation conditions allowed the determination of glufosinate, AMPA and glyphosate with detection limits of 2.8, 3.6 and 32.2 ng/mL, respectively. These detection limits were comparable to those of 1.4, 1.9 and 23.8 ng/mL obtained from conventional pre-capillary derivatization. Furthermore, repeatability better than 0.40% for migration time and 3.4% for peak area, as well as shorter migration time, was obtained. The method was successfully applied to the analysis of spiked river water sample with satisfactory results. PMID:17412355

  17. A review of organochlorine pesticide residues in Swainson's hawk eggs

    USGS Publications Warehouse

    Henny, C.J.

    1985-01-01

    U. s. Fish and Wildlife Service research projects during the last 10 years in the Pacific Northwest resulted in the collecting of a sample egg from 35 Swainson's Hawk nests (Henny and Kaiser, 1979. Murrelet 60:2-5; Henny et al. 1984. Raptor Research 18:41-48). Pesticide residues, eggshell thickness, and reproductive success from these nests will be reviewed. In addition, egg residues from other published studies in the Pacific Northwest and elsewhere will be discussed.

  18. International Harmonization of Food Safety Assessment of Pesticide Residues.

    PubMed

    Ambrus, Árpád

    2016-01-13

    This paper summarizes the development of principles and methods applied within the program of the FAO/WHO Codex Alimentarius during the past 50 years for the safety assessment of pesticide residues in food and feed and establishing maximum residue limits (MRLs) to promote free international trade and assure the safety of consumers. The role of major international organizations in this process, the FAO capacity building activities, and some problematic areas that require special attention are briefly described. PMID:25660755

  19. Responses of the iguanid lizard Anolis carolinensis to four organophosphorus pesticides

    USGS Publications Warehouse

    Hall, R.J.; Clark, D.R., Jr.

    1982-01-01

    Dose related mortality and cholinesterase effects of parathion, methyl parathion, azinphos-methyl and malathion on Anolis carolinensis were investigated. The comparative effects of the four compounds on fish, birds and mammals are well known, but the effects of organophosphates on reptiles have not been studied critically. Sensitivity and patterns of mortality from exposure to the pesticides resemble those of birds and mammals rather than those of other poikilothermic vertebrates. Possible symptoms of epinephrine accumulation were observed in exposed animals; this side effect is consistent with the known mechanisms of the pesticides. Our findings indicate that brain cholinesterase activity is related to dose, that 50% inhibition of cholinesterase is associated with death and that 40% inhibition indicates sublethal exposure. Anolis lizards are frequently exposed to pesticides in the field and they may be useful in monitoring the hazards posed to a variety of wildlife species.

  20. CHARACTERIZING PESTICIDE RESIDUE TRANSFER EFFICIENCIES USING FLUORESCENT TRACER IMAGING TECHNIQUES

    EPA Science Inventory

    To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study was conducted to identify the important pa...

  1. Sampling and sample processing in pesticide residue analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proper sampling and sample processing in pesticide residue analysis of food and soil has always been essential to obtain accurate results, but the subject is becoming a greater concern as approximately 100 mg test portions are being analyzed with automated high-throughput analytical methods by agroc...

  2. PESTICIDE SURFACE RESIDUE MEASUREMENTS BY A PRESS SAMPLER

    EPA Science Inventory

    Pesticides on household surfaces are a source of exposure to children. Accurate measurements of residues on surfaces are needed to determine amounts available for transfer to foods and other objects handled or eaten by a child. Wiping the surface with a solvent has been the acc...

  3. 5th Latin American pesticide residue workshop (LAPRW 2015)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This invited editorial proceedings article introduces the 6 research papers published in the special topical collection for the 5th Latin American Pesticide Residue Workshop held in Santiago, Chile, May 10-13, 2015. The meeting was a great success with more than 50 talks, 140 posters, 21 vendors, a...

  4. 9 CFR 318.16 - Pesticide chemicals and other residues in products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or...

  5. 9 CFR 318.16 - Pesticide chemicals and other residues in products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or...

  6. 9 CFR 318.16 - Pesticide chemicals and other residues in products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or...

  7. 9 CFR 318.16 - Pesticide chemicals and other residues in products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or...

  8. 9 CFR 318.16 - Pesticide chemicals and other residues in products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or...

  9. THE DETERMINATION OF ORGANOPHOSPHORUS PESTICIDES IN INDUSTRIAL AND MUNICIPAL WASTEWATER: METHOD 622

    EPA Science Inventory

    This is a gas chromatographic (GC) method applicable to the determination of selected pesticides in municipal and industrial discharges as provided under 40CFR 136.1. A sample is solvent extracted with methylene chloride using a separatory funnel. The extract is concentrated and ...

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

    EPA Science Inventory

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

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

    PubMed

    Fujioka, Kazutoshi; Casida, John E

    2007-08-01

    Pesticide detoxification is a central feature of selective toxicity and safety evaluation. Two of the principal enzymes involved are GSH S-transferases (GSTs) and cytochrome P450s acting alone and together. More than 100 pesticides are organophosphorus (OP) compounds, but with few exceptions, their GSH conjugates have not been directly observed in vitro or in vivo. The major insecticides chlorpyrifos (CP) and diazinon are of particular interest as multifunctional substrates with diverse metabolites, while ClP(S)(OEt) 2 and the cotton defoliant tribufos are possible precursors of phosphorylated GSH conjugates. Formation of GSH conjugates by GST with GSH was studied in vitro with and without metabolic activation by human liver microsomes or P450 3A4 with NADPH. Metabolites were analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). Five GSH conjugates were identified from CP and chlorpyrifos oxon (CPO), i.e., GSCP and GSCPO in which the 6-chloro substituent of CP and CPO, respectively, is displaced by GSH; S-(3,5,6-trichloropyridin-2-yl)glutathione; S-(3,5-dichloro-6-hydroxypyridin-2-yl)glutathione; and S-ethylglutathione. GST of a human liver microsomal preparation but not P450 3A4 with GSH metabolized CP to GSCP. With GST and GSH, diazinon and diazoxon gave S-(2-isopropyl-4-methylpyrimidin-6-yl)glutathione and ClP(S)(OEt) 2 yielded GSP(S)(OEt) 2. With microsomes, NADPH, GST, and GSH tribufos gave GSP(O)(SBu) 2. The liver of intraperitoneally treated mice contained GSCP from CP, GSP(S)(OEt) 2 from ClP(S)(OEt) 2, and GSP(O)(SBu) 2 from tribufos. GSP(S)(OEt) 2 and GSP(O)(SBu) 2 are the first S-phosphoglutathione metabolites observed in vitro and in vivo directly by LC-ESI-MS. Nine other OP pesticides gave only O-dealkylation in the GST/GSH system. GST-catalyzed metabolism joins P450s and hydrolases as important contributors to OP detoxification. PMID:17645302

  12. Trace analysis of some organophosphorus pesticides in rice samples using ultrasound-assisted dispersive liquid-liquid microextraction and high-performance liquid chromatography.

    PubMed

    Sharafi, Kiomars; Fattahi, Nazir; Mahvi, Amir Hossein; Pirsaheb, Meghdad; Azizzadeh, Nahid; Noori, Masomeh

    2015-03-01

    An ultrasound-assisted dispersive liquid-liquid microextraction based on solidification of a floating organic drop method followed by high-performance liquid chromatography was developed for the extraction, preconcentration, and determination of trace amounts of organophosphorus pesticides in rice samples. Variables affecting the performance of both steps were thoroughly investigated. Some effective parameters on extraction were studied and optimized. Under the optimum conditions, recoveries for rice sample are in the range of 58.0-66.0%. The calibration graphs are linear in the range of 4-800 μg/kg and, limits of detection and limits of quantification are in the range of 1.5-3 and 4.2-8.5 μg/kg, respectively. The relative standard deviation for 50.0 μg/kg of organophosphorus pesticides in rice sample are in the range of 4.4-5.1% (n = 5). The obtained results show that proposed method is a fast and simple method for the determination of pesticides in cereals. PMID:25641828

  13. Bioenergy residues as novel sorbents to clean up pesticide pollution

    NASA Astrophysics Data System (ADS)

    Mukherjee, Santanu

    2016-04-01

    Worldwide, water contamination from agricultural use of pesticides has received increasing attention within the last decades. In general, sources of pesticide water pollution are categorized into diffuse (stemming from treated fields) and point sources (stemming from farmyards and spillages). Research has demonstrated that 40 to 90% of surface water pesticide contamination is due to point source pollution. To reduce point pollution from farm yards, where the spray equipment is washed, biobed or biofilter systems are used to treat the washing water. The organic material usually used in these systems is often not environmentally sustainable (e.g. peat) and incorporated organic material such as straw leads to a highly heterogeneous water flow, with negative effects on the retention and degradation behavior of the pesticides. Therefore, the objective of this study was to assess the suitability of alternative materials based on bioenergy residues (biochar and digestate) for use in biofilters. To this aim the sorption-desorption potential of three contrasting pesticides (bentazone, boscalid, and pyrimethanil) on mixtures of soil with digestate and/or biochar were investigated in laboratory batch equilibrium experiments. The results indicate that the mixture of digestate and biochar increased pesticide sorption potential, whereby in all cases, the Kd des / Kf des values were lower than the Kd ads / Kf ads values indicating that the retention of the pesticides was weak. Thus, as Kf des were lower than the Kf ads values and H values were below 1, it can be concluded that the biomixtures presented negative desorption (higher hysteresis) in those cases. A higher Kd (>78 L kg-1), Kf (>400 μM1-1/nf L1/nfkg-1) and KL (>40 L kg-1) was obtained for all pesticides for the digestate and biochar based mixtures, which had a higher organic matter content. However, lower sorption of the pesticides was observed in blank soil compared to the other biomixtures, which was attributed to the

  14. Organochlorine pesticide residues in cow's milk and butter in Mexico.

    PubMed

    Waliszewski, S M; Pardío, V T; Waliszewski, K N; Chantiri, J N; Aguirre, A A; Infanzón, R M; Rivera, J

    1997-12-01

    This monitoring study of 355 samples of cow's milk collected from the central region of Veracruz state and 448 samples of national butter brands was conducted to determine the contamination levels of organochlorine pesticides. The results obtained for mean HCH levels were 0.094 and 0.093 mg/kg on fat basis in cow's milk and butter samples, respectively. The mean DDT levels were 0.159 and 0.049 mg/kg, respectively. In relation to cow's milk, the total HCH levels in Veracruz state were higher but total DDT levels were comparable to those reported in other countries. On the other hand, organochlorine levels detected in national brand butter samples were lower than those found in other countries, where these pesticides are still used in sanitary actions. These results confirmed that dairy products in Mexico presented organochlorine pesticide residues (owing to their use in sanitary actions) indicating a human exposure through these food products. PMID:9496657

  15. Proficiency test on the determination of pesticide residues in grapes with multi-residue methods.

    PubMed

    Dehouck, Pieter; Grimalt, Susana; Dabrio, Marta; Cordeiro, Fernando; Fiamegos, Yiannis; Robouch, Piotr; Fernández-Alba, Amadeo R; de la Calle, Beatriz

    2015-05-22

    This manuscript presents the results of the International Measurement Evaluation Programme 37 (IMEP-37) study, a proficiency test (PT) which was organised to assess the world-wide performance of food control laboratories on the determination of pesticide residues in grapes. This PT supports the implementation of Regulation (EC) No 396/2005 on maximum residue levels of pesticides in or on food and feed of plant and animal origin. Eighty-one participants reported results, forty from EU Member States and forty-one from outside the EU. The test item was a grape sample spiked with 20 selected pesticides. The results of the participants were rated with z- and zeta (ζ-) scores in accordance with ISO 13528 and ISO 17043. The standard deviation for the proficiency assessment, σˆ, of this PT was set at 25% for the 20 measured pesticides based on previous experience with similar measurands. The results reported to IMEP-37 showed that the participants performed satisfactorily, ranging from 81% (carbendazim) to 97% (azoxystrobin, penconazole, pyrimethanil) of the participating laboratories. However, only 30% of the participants managed to analyze all pesticides satisfactorily. Overall, the performance of the participants in this PT was good but there is room for improvement in the development of multi-residue methods for the simultaneous analysis of a large number of pesticides with an increased accuracy. PMID:25888097

  16. Polyacrylic acid-coated cerium oxide nanoparticles: An oxidase mimic applied for colorimetric assay to organophosphorus pesticides.

    PubMed

    Zhang, Shi-Xiang; Xue, Shi-Fan; Deng, Jingjing; Zhang, Min; Shi, Guoyue; Zhou, Tianshu

    2016-11-15

    It is important and urgent to develop reliable and highly sensitive methods that can provide on-site and rapid detection of extensively used organophosphorus pesticides (OPs) for their neurotoxicity. In this study, we developed a novel colorimetric assay for the detection of OPs based on polyacrylic acid-coated cerium oxide nanoparticles (PAA-CeO2) as an oxidase mimic and OPs as inhibitors to suppress the activity of acetylcholinesterase (AChE). Firstly, highly dispersed PAA-CeO2 was prepared in aqueous solution, which could catalyze the oxidation of TMB to produce a color reaction from colorless to blue. And the enzyme of AChE was used to catalyze the substrate of acetylthiocholine (ATCh) to produce thiocholine (TCh). As a thiol-containing compound with reducibility, TCh can decrease the oxidation of TMB catalyzed by PAA-CeO2. Upon incubated with OPs, the enzymatic activity of AChE was inhibited to produce less TCh, resulting in more TMB catalytically oxidized by PAA-CeO2 to show an increasing blue color. The two representative OPs, dichlorvos and methyl-paraoxon, were tested using our proposed assay. The novel assay showed notable color change in a concentration-dependent manner, and as low as 8.62 ppb dichlorvos and 26.73 ppb methyl-paraoxon can be readily detected. Therefore, taking advantage of such oxidase-like activity of PAA-CeO2, our proposed colorimetric assay can potentially be a screening tool for the precise and rapid evaluation of the neurotoxicity of a wealth of OPs. PMID:27208478

  17. A Disposable Organophosphorus Pesticides Enzyme Biosensor Based on Magnetic Composite Nano-Particles Modified Screen Printed Carbon Electrode

    PubMed Central

    Gan, Ning; Yang, Xin; Xie, Donghua; Wu, Yuanzhao; Wen, Weigang

    2010-01-01

    A disposable organophosphorus pesticides (OPs) enzyme biosensor based on magnetic composite nanoparticle-modified screen printed carbon electrodes (SPCE) has been developed. Firstly, an acetylcholinesterase (AChE)-coated Fe3O4/Au (GMP) magnetic nanoparticulate (GMP-AChE) was synthesized. Then, GMP-AChE was absorbed on the surface of a SPCE modified by carbon nanotubes (CNTs)/nano-ZrO2/prussian blue (PB)/Nafion (Nf) composite membrane by an external magnetic field. Thus, the biosensor (SPCE│CNTs/ZrO2/PB/Nf│GMP-AChE) for OPs was fabricated. The surface of the biosensor was characterized by scanning electron micrography (SEM) and X-ray fluorescence spectrometery (XRFS) and its electrochemical properties were studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The degree of inhibition (A%) of the AChE by OPs was determined by measuring the reduction current of the PB generated by the AChE-catalyzed hydrolysis of acetylthiocholine (ATCh). In pH = 7.5 KNO3 solution, the A was related linearly to the concentration of dimethoate in the range from 1.0 × 10−3–10 ng·mL−1 with a detection limit of 5.6 × 10−4 ng·mL−1. The recovery rates in Chinese cabbage exhibited a range of 88%–105%. The results were consistent with the standard gas chromatography (GC) method. Compared with other enzyme biosensors the proposed biosensor exhibited high sensitivity, good selectivity with disposable, low consumption of sample. In particular its surface can be easily renewed by removal of the magnet. The convenient, fast and sensitive voltammetric measurement opens new opportunities for OPs analysis. PMID:22315558

  18. Organophosphorus pesticide and ester analysis by using comprehensive two-dimensional gas chromatography with flame photometric detection.

    PubMed

    Liu, Xiangping; Li, Dengkun; Li, Jiequan; Rose, Gavin; Marriott, Philip J

    2013-12-15

    Thirty-seven phosphorus (P)-containing compounds comprising organophosphorus pesticides and organophosphate esters were analyzed by using comprehensive two-dimensional gas chromatography with flame photometric detection in P mode (GC × GC-FPD(P)), with a non-polar/moderately polar column set. A suitable modulation temperature and period was chosen based on experimental observation. A number of co-eluting peak pairs on the (1)D column were well separated in 2D space. Excellent FPD(P) detection selectivity, responding to compounds containing the P atom, produces clear 2D GC × GC plots with little interference from complex hydrocarbon matrices. Limits of detection (LOD) were within the range of 0.0021-0.048 μmol L(-1), and linear calibration correlation coefficients (R(2)) for all 37 P-compounds were at least 0.998. The P-compounds were spiked in 2% diesel and good reproducibility for their response areas and retention times was obtained. Spiked recoveries were 88%-157% for 5 μg L(-1) and 80%-138% for 10 μg L(-1) spiked levels. Both (1)tR and (2)tR shifts were noted when the content of diesel was in excess of 5% in the matrix. Soil samples were analyzed by using the developed method; some P-compounds were positively detected. In general, this study shows that GC × GC-FPD(P) is an accurate, sensitive and simple method for P-compound analysis in complicated environmental samples. PMID:24238476

  19. A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices.

    PubMed

    Armstrong, Jenna L; Dills, Russell L; Yu, Jianbo; Yost, Michael G; Fenske, Richard A

    2014-01-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. XAD-2 resin and polyurethane foam (PUF) matrices were extracted with acetonitrile containing stable-isotope labeled internal standards (ISTD). Analysis was accomplished in Multiple Reaction Monitoring (MRM) mode, and analytes in unknown samples were identified by retention time (±0.1 min) and qualifier ratio (±30% absolute) as compared to the mean of calibrants. For all compounds, calibration linearity correlation coefficients were ≥0.996. Limits of detection (LOD) ranged from 0.15-1.1 ng/sample for CPF, CPF-O, AZM, and AZM-O on active sampling matrices. Spiked fortification recoveries were 78-113% from XAD-2 active air sampling tubes and 71-108% from PUF active air sampling tubes. Storage stability tests also yielded recoveries ranging from 74-94% after time periods ranging from 2-10 months. The results demonstrate that LC-MS/MS is a sensitive method for determining these compounds from two different matrices at the low concentrations that can result from spray drift and long range transport in non-target areas following agricultural applications. In an inter-laboratory comparison, the limit of quantification (LOQ) for LC-MS/MS was 100 times lower than a typical gas chromatography-mass spectrometry (GC-MS) method. PMID:24328542

  20. Fast gas chromatography for pesticide residues analysis using analyte protectants.

    PubMed

    Kirchner, Michal; Húsková, Renáta; Matisová, Eva; Mocák, Ján

    2008-04-01

    Fast GC-MS with narrow-bore columns combined with effective sample preparation technique (QuEChERS method) was used for evaluation of various calibration approaches in pesticide residues analysis. In order to compare the performance of analyte protectants (APs) with matrix-matched standards calibration curves of selected pesticides were searched in terms of linearity of responses, repeatability of measurements and reached limit of quantifications utilizing the following calibration standards in the concentration range 1-500 ng mL(-1)(the equivalent sample concentration 1-500 microg kg(-1)): in neat solvent (acetonitrile) with/without addition of APs, matrix-matched standards with/without addition of APs. For APs results are in a good agreement with matrix-matched standards. To evaluate errors of determination of concentration synthetic samples at concentration level of pesticides 50 ng mL(-1) (50 microg kg(-1)) were analyzed and quantified using the above given standards. For less troublesome pesticides very good estimation of concentration was obtained utilizing APs, while for more troublesome pesticides such as methidathion, malathion, phosalone and deltamethrin significant overestimation reaching up to 80% occurred. According to presented results APs can be advantegously used for "easy" pesticides determination. For "difficult" pesticides an alternative calibration approach is required for samples potentially violating MRLs. An example of real sample measurement is shown. In this paper also the use of internal standards (triphenylphosphate (TPP) and heptachlor (HEPT)) for peak areas normalization is discussed in terms of repeatability of measurements and quantitative data obtained. TPP normalization provided slightly better results than the use of absolute peak areas measurements on the contrary to HEPT. PMID:17920613

  1. Pesticide residue in water--a challenging task in India.

    PubMed

    Agarwal, Akriti; Prajapati, Rajmani; Singh, Om Pal; Raza, S K; Thakur, L K

    2015-02-01

    Modern agriculture practices reveal an increase in use of pesticides to meet the food demand of increasing population which results in contamination of the environment. In India, crop production increased to 100 %, but the cropping area has increased marginally by 20 %. Pesticides have played a major role in achieving the maximum crop production but maximum usage and accumulation of pesticide residues is highly detrimental to aquatic and other ecosystem. Pesticide residues in drinking water have become a major challenge over the last few years. It has been monitored in public water supply resources in National capital territory, i.e., Delhi. Organochlorine pesticides (OCPs), mainly isomers of hexachlorohexane (HCH), dichloro-diphenyl-trichloroethane (DDT), endosulphan, endrin, aldrin, dieldrin, and heptachlore, were identified from potable water samples. Results suggested that continuous consumption of contaminated water can pose severe health threats to local residents of this area. Central Pollution Control Board (CPCB), Delhi, had found α and β isomers of endosulphan residues in the Yamuna river. High concentrations of γ-HCH (0.259 μg/l) and malathion (2.618 μg/l) were detected in the surface water samples collected from the river Ganga in Kanpur, Uttar Pradesh (UP). High concentration of methyl parathion, endosulfan, and DDT were observed in water samples collected from the river at Bhagalpur, Bihar. The Industrial Toxicology Research Centre (ITRC), Lucknow (UP) study also found 0.5671 ppb concentrations of endosulfan in the river at Allahabad, UP. Similar results were found in other water samples in India. PMID:25638058

  2. Colorimetric sensor array for detection and identification of organophosphorus and carbamate pesticides.

    PubMed

    Qian, Sihua; Lin, Hengwei

    2015-01-01

    Due to relatively low persistence and high effectiveness for insect and pest eradication, organophosphates (OPs) and carbamates are the two major classes of pesticides that broadly used in agriculture. Hence, the sensitive and selective detection of OPs and carbamates is highly significant. In this current study, a colorimetric sensor array comprising five inexpensive and commercially available thiocholine and H2O2 sensitive indicators for the simultaneous detection and identification of OPs and carbamates is developed. The sensing mechanism of this array is based on the irreversible inhibition capability of OPs and carbamates to the activity of acetylcholinesterase (AChE), preventing production of thiocholine and H2O2 from S-acetylthiocholine and acetylcholine and thus resulting in decreased or no color reactions to thiocholine and H2O2 sensitive indicators. Through recognition patterns and standard statistical methods (i.e., hierarchical clustering analysis and principal component analysis), the as-developed array demonstrates not only discrimination of OPs and carbamates from other kinds of pesticides but, more interestingly, identification of them exactly from each other. Moreover, this array is experimentally confirmed to have high selectivity and sensitivity, good anti-interference capability, and potential applications in real samples for OPs and carbamates. PMID:25913282

  3. Pesticide Residues and Bees – A Risk Assessment

    PubMed Central

    Sanchez-Bayo, Francisco; Goka, Koichi

    2014-01-01

    Bees are essential pollinators of many plants in natural ecosystems and agricultural crops alike. In recent years the decline and disappearance of bee species in the wild and the collapse of honey bee colonies have concerned ecologists and apiculturalists, who search for causes and solutions to this problem. Whilst biological factors such as viral diseases, mite and parasite infections are undoubtedly involved, it is also evident that pesticides applied to agricultural crops have a negative impact on bees. Most risk assessments have focused on direct acute exposure of bees to agrochemicals from spray drift. However, the large number of pesticide residues found in pollen and honey demand a thorough evaluation of all residual compounds so as to identify those of highest risk to bees. Using data from recent residue surveys and toxicity of pesticides to honey and bumble bees, a comprehensive evaluation of risks under current exposure conditions is presented here. Standard risk assessments are complemented with new approaches that take into account time-cumulative effects over time, especially with dietary exposures. Whilst overall risks appear to be low, our analysis indicates that residues of pyrethroid and neonicotinoid insecticides pose the highest risk by contact exposure of bees with contaminated pollen. However, the synergism of ergosterol inhibiting fungicides with those two classes of insecticides results in much higher risks in spite of the low prevalence of their combined residues. Risks by ingestion of contaminated pollen and honey are of some concern for systemic insecticides, particularly imidacloprid and thiamethoxam, chlorpyrifos and the mixtures of cyhalothrin and ergosterol inhibiting fungicides. More attention should be paid to specific residue mixtures that may result in synergistic toxicity to bees. PMID:24718419

  4. Pesticide residues and bees--a risk assessment.

    PubMed

    Sanchez-Bayo, Francisco; Goka, Koichi

    2014-01-01

    Bees are essential pollinators of many plants in natural ecosystems and agricultural crops alike. In recent years the decline and disappearance of bee species in the wild and the collapse of honey bee colonies have concerned ecologists and apiculturalists, who search for causes and solutions to this problem. Whilst biological factors such as viral diseases, mite and parasite infections are undoubtedly involved, it is also evident that pesticides applied to agricultural crops have a negative impact on bees. Most risk assessments have focused on direct acute exposure of bees to agrochemicals from spray drift. However, the large number of pesticide residues found in pollen and honey demand a thorough evaluation of all residual compounds so as to identify those of highest risk to bees. Using data from recent residue surveys and toxicity of pesticides to honey and bumble bees, a comprehensive evaluation of risks under current exposure conditions is presented here. Standard risk assessments are complemented with new approaches that take into account time-cumulative effects over time, especially with dietary exposures. Whilst overall risks appear to be low, our analysis indicates that residues of pyrethroid and neonicotinoid insecticides pose the highest risk by contact exposure of bees with contaminated pollen. However, the synergism of ergosterol inhibiting fungicides with those two classes of insecticides results in much higher risks in spite of the low prevalence of their combined residues. Risks by ingestion of contaminated pollen and honey are of some concern for systemic insecticides, particularly imidacloprid and thiamethoxam, chlorpyrifos and the mixtures of cyhalothrin and ergosterol inhibiting fungicides. More attention should be paid to specific residue mixtures that may result in synergistic toxicity to bees. PMID:24718419

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

    PubMed

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

    2016-01-01

    Pesticide residues in fruits and vegetables are among the primary sources of pesticide exposure through diet, but the lack of adequate measurements hinder the research on health effects of pesticide residues. Pesticide Residue Burden Score (PRBS) for estimating overall dietary pesticide intake, organochlorine pesticide score (OC-PRBS) and organophosphate pesticide score (OP-PRBS) for estimating organochlorine and organophosphate pesticides-specific intake, respectively, were derived using U.S. Department of Agriculture Pesticide Data Program data and National Health and Nutrition Examination Survey (NHANES) food frequency questionnaire data. We evaluated the performance of these scores by validating the scores against pesticide metabolites measured in urine or serum among 3,679 participants in NHANES using generalized linear regression. The PRBS was positively associated with a score summarizing the ranks of all pesticide metabolites in a linear fashion (p for linear trend <0.001). Furthermore, individuals in the top quintile of this score had urinary pesticide metabolite levels 13.0% (95% CI 8.3%-17.7%) higher than individuals in the lowest quintile. Similarly, we observed significant associations of the OC-PRBS and OP-PRBS with the levels of lipid-adjusted total serum organochlorine pesticides and urinary creatinine-adjusted organophosphate pesticides, respectively. The relative difference (RD) in average pesticide metabolite rank between extreme quintiles was 17.8% (95% CI: 11.1%-24.4%, p for trend <0.001) for the OP-PRBS, whereas the RD was marginally significant at 7.0% (95% CI: -0.5%-14.4%, p for trend 0.07) for the OC-PRBS. The PRBS and OP-PRBS had similar performance when they were derived from fruits and vegetables with high vs. low pesticide residues, respectively (p for trend <0.001 for all associations). The OP-PRBS was associated with all measured organophosphate pesticides, whereas the positive association between OC-PRBS and averaged measured

  6. Utilizing a novel sorbent in the solid phase extraction for simultaneous determination of 15 pesticide residues in green tea by GC/MS.

    PubMed

    Huo, Feifei; Tang, Hua; Wu, Xue; Chen, Dazhou; Zhao, Tan; Liu, Pei; Li, Lei

    2016-06-15

    Pesticide residues exceeding standard in green tea is a widespread problem of the world's attention, containing organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs), and pyrethroids. In this research, three dimensionally honeycomb Mg-Al layered double oxide (TDH-Mg-Al-LDO) combined with graphitized carbon black (GCB), packed as a column, was used as a novel solid phase extraction sorbent, applying in simultaneous determination of 15 pesticide residues in green tea coupled with GC-MS. Compared with different type of SPE column, it showed that TDH-Mg-Al-LDO exhibited great advantages in the extraction of 15 pesticide residues from green tea, which was seldom reported before. Different experiment conditions, such as combination order of Mg-Al-LDO and GCB, dosage of sorbents, type and volume of eluting solvent were thoroughly studied and optimized. The limits of detection (LODs) of 15 pesticides ranged from 0.9 to 24.2ng/g and the limits of quantifications (LOQs) were ranging from 3.0 to 80.0ng/g. The recoveries using this method at three spiked concentration levels (10, 100 and 500ng/g for Fenthion, P,P'-DDE, O,P'-DDT, P,P'-DDD and Bifenthrin, 100, 500 and 2000ng/g for the others) range from 71.1 to 119.0%. The relative standard deviation (RSD) was from 0.1 to 7.6% in all case. The result indicated that the proposed analytical method had been successfully applied for the simultaneous determination of 15 pesticide residues in commercial green tea. PMID:27183089

  7. Sister-chromatid exchanges and cell-cycle delay in Chinese hamster V79 cells treated with 9 organophosphorus compounds (8 pesticides and 1 defoliant).

    PubMed

    Chen, H H; Sirianni, S R; Huang, C C

    1982-03-01

    Significant increase of sister-chromatid exchanges (SCE) in V79 cells treated with 2 organophosphorus pesticides (OPP), fenthion and oxydemeton-methyl, was observed. The other 7 compounds (6 OPP and 1 defoliant) namely, amaze, azinphos-methyl, bolstar, DEF-defoliant, fensulfothion, monitor and nemacur caused no increase of SCE frequencies at the doses tested. All the compounds except fensulfothion and oxydemeton-methyl induced cell-cycle delay in varying degrees. Cell-cycle delay caused by an OPP was found to be dose-dependent. Based on these data as well as others reported, it would appear that OPP which induce no SCE increase and no or slight cell-cycle delay could be considered as good candidates to substitute the pesticides that have been found to be harmful to the environment. PMID:6211614

  8. Lactobacillus Casei Decreases Organophosphorus Pesticide Diazinon Cytotoxicity in Human HUVEC Cell Line

    PubMed Central

    Bagherpour Shamloo, Hasan; Golkari, Saber; Faghfoori, Zeinab; Movassaghpour, AliAkbar; Lotfi, Hajie; Barzegari, Abolfazl; Yari Khosroushahi, Ahmad

    2016-01-01

    Purpose: Exposure to diazinon can trigger acute and chronic toxicity and significantly induces DNA damage and proapoptotic effects in different human cells. Due to the significance of probiotic bacteria antitoxin effect, this study aimed to investigate the effect of Lactobacillus casei on diazinon (DZN) cytotoxicity in human umbilical vein endothelial cells (HUVEC) in vitro. Methods: The cytotoxicity assessments were performed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test, DAPI (4',6-diamidino-2-phenylindole) staining and flow cytometric methodologies. Results: Cytotoxic assessments through flow cytometry/ DAPI staining demonstrated that apoptosis is the main cytotoxic mechanism of diazinon in HUVEC cells and L. casei could decrease the diazinon cytotoxic effects on toxicants. Conclusion: the screen of total bacterial secreted metabolites can be considered as a wealthy source to find the new active compounds to introduce as reducing agricultural remained pesticide cytotoxicity effects on the human food chain. PMID:27478782

  9. Degradation of organophosphorus pesticide parathion methyl on nanostructured titania-iron mixed oxides

    NASA Astrophysics Data System (ADS)

    Henych, Jiří; Štengl, Václav; Slušná, Michaela; Matys Grygar, Tomáš; Janoš, Pavel; Kuráň, Pavel; Štastný, Martin

    2015-07-01

    Titania-iron mixed oxides with various Ti:Fe ratio were prepared by homogeneous hydrolysis of aqueous solutions of titanium(IV) oxysulphate and iron(III) sulphate with urea as a precipitating agent. The synthesized samples were characterized by X-ray diffraction, Raman and infrared spectroscopy, scanning and transmission electron microscopy, XRF analysis, specific surface area (BET) and porosity determination (BJH). These oxides were used for degradation of organophosporus pesticide parathion methyl. The highest degradation efficiency approaching <70% was found for the samples with Ti:Fe ratio 0.25:1 and 1:0.25. Contrary, parathion methyl was not degraded on the surfaces of pure oxides. In general, the highest degradation rate exhibited samples consisted of the iron or titanium oxide containing a moderate amount of the admixture. However, distinct correlations between the degradation rate and the sorbent composition were not identified.

  10. Organochlorine pesticide residues in chicken eggs: a survey.

    PubMed

    Kahunyo, J M; Froslie, A; Maitai, C K

    1988-01-01

    One hundred and five chicken egg samples were taken from seven geographical locations in Kenya and analyzed for organochlorine pesticide residues using gas-liquid chromatography. Nine organochlorine compounds were detected: alpha- and gamma-HCH/BHC (hexachlorocyclohexane/benzene hexachloride), aldrin, dieldrin, p,p'-DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], p,p'-DDD (TDE) [2,2-bis(p-chlorophenyl)-1,1-dichloroethane] (tetrachlorodiphenylethane), o,p'-DDD [2-(o-chlorophenyl)-2-(p-chlorophenyl)-1,1-dichloroethane], o,p'-DDT [2-(o-chlorophenyl)-2-(p-chlorophenyl)-1,1,1-trichloroethane], and p,p'-DDT. Eighteen of the samples contained DDT levels exceeding the practical residue limit (0.5 ppm). The mean DDT residue content was 0.68 ppm, a result influenced greatly by the high contamination in the 18 samples. Both individual and mean residue levels for other organochlorine pesticides detected were well within the respective practical residue limits. PMID:3411637

  11. Pesticide residues in food--acute dietary exposure.

    PubMed

    Hamilton, Denis; Ambrus, Arpád; Dieterle, Roland; Felsot, Allan; Harris, Caroline; Petersen, Barbara; Racke, Ken; Wong, Sue-Sun; Gonzalez, Roberto; Tanaka, Keiji; Earl, Mike; Roberts, Graham; Bhula, Raj

    2004-04-01

    Consumer risk assessment is a crucial step in the regulatory approval of pesticide use on food crops. Recently, an additional hurdle has been added to the formal consumer risk assessment process with the introduction of short-term intake or exposure assessment and a comparable short-term toxicity reference, the acute reference dose. Exposure to residues during one meal or over one day is important for short-term or acute intake. Exposure in the short term can be substantially higher than average because the consumption of a food on a single occasion can be very large compared with typical long-term or mean consumption and the food may have a much larger residue than average. Furthermore, the residue level in a single unit of a fruit or vegetable may be higher by a factor (defined as the variability factor, which we have shown to be typically x3 for the 97.5th percentile unit) than the average residue in the lot. Available marketplace data and supervised residue trial data are examined in an investigation of the variability of residues in units of fruit and vegetables. A method is described for estimating the 97.5th percentile value from sets of unit residue data. Variability appears to be generally independent of the pesticide, the crop, crop unit size and the residue level. The deposition of pesticide on the individual unit during application is probably the most significant factor. The diets used in the calculations ideally come from individual and household surveys with enough consumers of each specific food to determine large portion sizes. The diets should distinguish the different forms of a food consumed, eg canned, frozen or fresh, because the residue levels associated with the different forms may be quite different. Dietary intakes may be calculated by a deterministic method or a probabilistic method. In the deterministic method the intake is estimated with the assumptions of large portion consumption of a 'high residue' food (high residue in the sense

  12. Production and characterization of a single-chain variable fragment linked alkaline phosphatase fusion protein for detection of O,O-diethyl organophosphorus pesticides in a one-step enzyme-linked immunosorbent assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A single-chain variable fragment (scFv) and alkaline phosphatase (AP) fusion protein for detection of O, O-diethyl organophosphorus pesticides (OPs) was produced and characterized. The scFv gene was prepared by cloning VL and VH genes from a hybridoma cell secreting monoclonal antibody with broad-s...

  13. Pesticide residue analysis in cereal-based baby foods using multi-walled carbon nanotubes dispersive solid-phase extraction.

    PubMed

    González-Curbelo, Miguel Angel; Asensio-Ramos, María; Herrera-Herrera, Antonio V; Hernández-Borges, Javier

    2012-07-01

    In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their metabolites, (disulfoton-sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos-sulfone, disulfoton-sulfone and fensulfothion) in three different types of commercial cereal-based baby foods. Dispersive solid-phase extraction (dSPE) with multi-walled carbon nanotubes (MWCNTs) was used together with gas chromatography with nitrogen phosphorus detection. Most favorable conditions involved a previous ultrasound-assisted extraction of the sample with acetonitrile containing formic acid. After evaporation of the extract and redissolution in water, a dSPE procedure was carried out with MWCNTs. The whole method was validated in terms of repeatability, linearity, precision and accuracy and matrix effect was also evaluated. Absolute recoveries were in the range 64-105 % with relative standard deviation values below 7.6 %. Limits of quantification achieved ranged from 0.31 to 5.50 μg/kg, which were lower than the European Union maximum residue limits for pesticide residues in cereal-based baby foods. PMID:22623047

  14. Monitoring of Certain Pesticide Residues and Some Heavy Metals in Fresh Cow`s Milk at Gharbia Governorate, Egypt

    NASA Astrophysics Data System (ADS)

    Nasr, I. N.; Sallam, A. A. A.; Abd El-Khair, A. A.

    This monitoring study of 40 samples of cow's milk collected from different locations at Gharbia Governorate during the four different seasons of the years 2005-2006, was conducted to determine the contamination levels of seven pesticide residues including four organophosphorus (chlorpyrifos, diazinon, dimethoate and malathion) and three synthetic pyrethroides (cypermethrin, deltamethrin and fenvelerate), as well as five heavy metals (copper, iron, cadmium, zinc and lead). The results showed that there were no contamination with investigated pesticide residues found in all analyzed samples, except for malathion, which was detected in a single sample with a negligible existence (0.018 mg kg-1), by ratio of (0.02%) of all samples. In relation to heavy metals detection, data revealed that all milk samples were contaminated with heavy metals all year around. The contamination with heavy metals was generally dominated at summer season. Level of lead was higher than other metals. The mean levels of Cu, Fe, Cd, Zn and Pb were 0.251, 0.607, 0.159, 0.371 and 2.462 mg kg-1, respectively. Cu, Fe and Zn level were under the permissible limits, while the Cd and Pb were exceeded the permissible limits, indicating serious heavy metals pollution in the region.

  15. Level of organochlorine pesticide residues in dry fruit nuts.

    PubMed

    Pandey, Pragya; Raizada, R B; Srivastava, L P

    2010-09-01

    The use of pesticides on cash crops and exportable food commodities had always been a serious concern. Fruits form one of the important constituents of human diet, in that they give one third of the requirement of calories, vitamins, and minerals. This study has been carried out to determine the level of organochlorine pesticides namely HCH, DDT and Endosulfan in raw fruit nuts. Nuts have proteins and high level of fat content. These properties of nuts attract organochlorine pesticides to accumulate. The analysis of organochlorine pesticide residues in commonly used dry fruits like Cashewnut, Walnut, Coconut, Chilgoza, Chironji, Makhana, Resins, Apricot, Almonds, Date palm, Pistachio nut collected from local market of Lucknow India has indicated presence of very low level of HCH (0.007-1.328 mg kg(-1)), DDT(ND-0.140 mg kg(-1)) and Endosulfan (ND-0.091 mg kg(-1)). There are no MRL values established for nuts in the country. This finding is based on a smaller number of samples, which however suggest that the presence of low level of DDT, HCH and Endosulfan might be due to environmental rather than direct exposure. PMID:21387926

  16. Determination of pesticide residues in fruit-based soft drinks.

    PubMed

    García-Reyes, Juan F; Gilbert-López, Bienvenida; Molina-Díaz, Antonio; Fernández-Alba, Amadeo R

    2008-12-01

    Here we report the first worldwide reconnaissance study of the presence and occurrence of pesticides in fruit-based soft drinks. While there are strict regulations and exhaustive controls for pesticides in fruits, vegetables, and drinking water, scarce attention has been paid to highly consumed derivate products, which may contain these commodities as ingredients. In the case of the fruit-based soft drinks industry, there are no clear regulations, relating to pesticides, which address them, even when there is significant consumption in vulnerable groups such as children. In this work, we have developed a screening method to search automatically for up to 100 pesticides in fruit-based soft drinks extracts based on the application of liquid chromatography-electrospray time-of-flight mass spectrometry (LC-TOF MS). The sample extracts injected were obtained by a preliminary sample treatment step based on solid-phase extraction using hydrophilic-lipophilic balanced polymer-based reverse phase cartridges and methanol as eluting solvent. Subsequent identification, confirmation, and quantitation were carried out by LC-TOF MS analysis: the confirmation of the target species was based on retention time matching and accurate mass measurements of protonated molecules ([M + H]+) and fragment ions (obtaining accuracy errors typically lower than 2 ppm). With the proposed method, we measured over 100 fruit-based soft drink samples, purchased from 15 different countries from companies with brands distributed worldwide and found relatively large concentration levels of pesticides in most of the samples analyzed. The concentration levels detected were of the micrograms per liter level, low when considering the European maximum residue levels (MRLs) set for fruits but very high (i.e., 300 times) when considering the MRLs for drinking or bottled water. The detected pesticides (carbendazim, thiabendazole, imazalil and its main degradate, prochloraz and its main degradate, malathion, and

  17. 77 FR 8755 - Receipt of a Pesticide Petition Filed for Temporary Tolerance Exemption for Residues of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... Residues of Prohydrojasmon in or on Various Commodities AGENCY: Environmental Protection Agency (EPA... residues of pesticide chemicals in or on various commodities. DATES: Comments must be received on or before... modification of a regulation in 40 CFR part 180 for residues of pesticide chemicals in or on various...

  18. Physiologically Based Pharmacokinetic/Pharmacodynamic Model for the Organophosphorus Pesticide Diazinon

    SciTech Connect

    Poet, Torka S.; Kousba, Ahmed A.; Dennison, Stephanie L.; Timchalk, Chuck

    2004-12-01

    Organophosphate (OP) insecticides like diazinon (DZN) constitute a large class of chemical insecticides that are widely utilized. The potential exists for significant exposures to a combination of OP pesticides from multiple routes. The objective of this research was to develop a physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) model capable of predicting the relationships between exposure route, bioactivation, detoxification, and acetylcholinesterase (AChE) inhibition. CYP450-mediated metabolism of DZN to the active oxon leads to inhibition of AChE at nerve endings. CYP450s also mediate detoxification of DZN to its pyrimidinol and A-esterase detoxifies the oxon to the pyrimidinol. The ultimate goal is to use this model to quantify systemic dosimetry and biological response from available environmental and personal exposure data. The model structure integrates CYP450 and esterase metabolism, route-dependent absorption, target tissue dosimetry, and dynamic response, to predict circulating blood levels of DZN and esterase inhibition in target organs. Metabolic rate constants for the CYP450-mediated conversion to the active oxon and the inactive pyrimidinol and the esterase-mediated deactivation of the oxon have been measured in vitro. The inhibition of AChE activity is a sensitive and relatively easy measure of exposure and is therefore the preferred descriptive endpoint. Esterase inhibition and regeneration rates have been described using in vitro calculations and parameter optimization to fit the model to AChE inhibition data. This descriptive model for DZN has been developed and has been shown to predict blood levels of the parent chemical and AChE inhibition in animal models. This PBPK/PD model will be linked to a existing PBPK model for chlorpyrifos to estimate the effects of exposures to a mixture of OPs and to describe target tissue dosimetry and effects in humans. These biologically relevant PBPK models will be integral to risk assessments for

  19. Exonuclease I-aided homogeneous electrochemical strategy for organophosphorus pesticide detection based on enzyme inhibition integrated with a DNA conformational switch.

    PubMed

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

    2016-02-15

    A novel enzyme inhibition-based homogeneous electrochemical biosensing strategy was designed for an organophosphorus pesticide assay based on exploiting the resistance of a mercury ion-mediated helper probe (HP) toward nuclease-catalyzed digestion and the remarkable diffusivity difference between HPs and the mononucleotides toward a negatively charged indium tin oxide (ITO) electrode. In particular, the mercury ion-mediated T-Hg(2+)-T base pairs facilitate the HP labeled with methylene blue (MB) to fold into a hairpin structure, preventing its digestion by exonuclease I, and thus resulting in a low electrochemical response because of the large electrostatic repulsion between the negatively charged ITO electrode and the HPs. The competitive binding by a thiol group (-SH), produced in the hydrolysis reaction of acetylthiocholine (ACh) chloride with acetylcholinesterase (AChE), removes mercury ions from the base pairs, causing a nuclease-catalyzed digestion, and the subsequent electrochemical response increase due to the weak electrostatic repulsion between the product-mononucleotides and the ITO electrode. Mercury ion-mediated HPs were first designed for pesticide detection and diazinon was chosen as the model target. Under the optimal experimental conditions, the approach exhibited high sensitivity for diazinon detection with a detection limit of 0.25 μg L(-1). The satisfactory results in the determination of diazinon in real samples demonstrate that the method possesses great potential for detecting organophosphorus pesticides. This new approach is expected to promote the exploitation of mercury-mediated base pair-based homogenous electrochemical biosensors in biochemical studies and in the food safety field. PMID:26839920

  20. Some organochlorine pesticide residues in fish species in Konya, Turkey.

    PubMed

    Kalyoncu, Leyla; Agca, Ihsan; Aktumsek, Abdurrahman

    2009-02-01

    The levels of organochlorine pesticides were measured in 18 fish species from Konya markets, Turkey. These species were selected on the basis of their importance to local human fish consumption. The extracted residues were analyzed on a micro capillary gas chromatograph equipped with an electron capture detector. Total 14 different organochlorine pesticides were determined. These residues were detected in all fish species, except in trout, horse mackerel and bonito. DDT and its metabolites and HCH were the predominant contaminants in fish muscles. The mean concentrations of summation operator DDT were in the range between 0.0008 and 0.0828 microg g(-1). DDT was the predominant residue in Sparus aurata. Detectable levels of HCH, aldrin, and heptachlor were found in most samples. However, dieldrin, endrin, beta endosulfan, p-p' DDT, and p-p' DDD were not found in Salmo trutta. The mean of endrin ranged from 0.0040 microg g(-1) (Triglia lineate) to 0.0326 microg g(-1) (Trachurus trachurus). These results give no indication of important health risks associated with the consumption of these fishes in Konya markets. PMID:19103455

  1. Monitoring of organochlorine pesticides residues in green mussels (Perna viridis) from the coastal area of Thailand.

    PubMed

    Boonyatumanond, Ruchaya; Jaksakul, Areerat; Puncharoen, Pornthip; Tabucanon, Monthip Sriratana

    2002-01-01

    The utilization of organochlorine pesticides for pest control chemical has been of great interest on residue contamination from biological organisms in the environment. Green mussel (Perna viridis) samples were monitored as bioindicators for assessment of the water quality in coastal waters along the Gulf of Thailand. Thirty-six samples were collected from 12 stations during 1997-1999 and analysed for 26 organochlorine pesticide compounds. This paper focuses on the contamination of organochlorine pesticide residues in green mussel (P. viridis) during 1997-1999. The limit of detection of all organochlorine pesticides compounds was at the range of 0.1-8.3 ng g(-1) wet weight and recovery 75-95%. The concentration of organochlorine pesticides residues in green mussel was lower than the maximum residue limit for aquatic animals as recommended by the Ministry of Public Health of Thailand. The trend of organochlorine pesticide residue contamination in this area decreased from 1989 to 1999. PMID:12152831

  2. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Disposition of imported tobacco exceeding pesticide... Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of test results from pesticide test samples, the Director shall notify the importer or entity responsible for...

  3. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Disposition of imported tobacco exceeding pesticide... Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of test results from pesticide test samples, the Director shall notify the importer or entity responsible for...

  4. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Disposition of imported tobacco exceeding pesticide... Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of test results from pesticide test samples, the Director shall notify the importer or entity responsible for...

  5. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Disposition of imported tobacco exceeding pesticide... Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of test results from pesticide test samples, the Director shall notify the importer or entity responsible for...

  6. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Disposition of imported tobacco exceeding pesticide... Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of test results from pesticide test samples, the Director shall notify the importer or entity responsible for...

  7. Organophosphorus pesticides markedly inhibit the activities of natural killer, cytotoxic T lymphocyte and lymphokine-activated killer: a proposed inhibiting mechanism via granzyme inhibition.

    PubMed

    Li, Qing; Nagahara, Noriyuki; Takahashi, Hidemi; Takeda, Kazuyoshi; Okumura, Ko; Minami, Masayasu

    2002-04-01

    We have previously found that diisopropyl methylphosphonate, an organophosphorus by-product generated during sarin synthesis in the Tokyo sarin disaster, significantly inhibited natural killer (NK) and cytotoxic T lymphocyte (CTL) activities. In the present study, to investigate whether organophosphorus pesticides (OPs) also affect NK and CTL activities, we firstly examined the effect of five OPs on human NK activity, and then the effect of Dimethyl 2,2-dichlorovinyl phosphate (DDVP), an OP on murine splenic NK, CTL and lymphokine-activated killer (LAK), and human LAK activities in vitro. To explore the underlying mechanism of decreased NK activity, we also investigated the effect of 4-(2-aminoethyl) benzenesulfonyl fluoride-HCl (p-ABSF), an inhibitor of serine proteases on NK, LAK and CTL activities, and the effect of DDVP on the activity of granzymes (serine proteases). We found that OPs significantly decreased human NK activity in a dose-dependent manner, but the degree of decrease in NK activity differed among the OPs investigated, and that DDVP significantly decreased NK, LAK and CTL activities in a dose-dependent manner, but the degree of decrease in these activities differed. p-ABSF showed a similar inhibitory pattern to DDVP, and had an additive inhibitory effect with DDVP on NK, LAK and CTL activities. We also found that DDVP significantly inhibited granzyme activity in a dose-dependent manner. These findings indicate that OPs significantly decrease NK, LAK and CTL activities in vitro via granzyme inhibition. PMID:11893417

  8. Requiring Pollutant Discharge Permits for Pesticide Applications that Deposit Residues in Surface Waters

    PubMed Central

    Centner, Terence; Eberhart, Nicholas

    2014-01-01

    Agricultural producers and public health authorities apply pesticides to control pests that damage crops and carry diseases. Due to the toxic nature of most pesticides, they are regulated by governments. Regulatory provisions require pesticides to be registered and restrictions operate to safeguard human health and the environment. Yet pesticides used near surface waters pose dangers to non-target species and drinking water supplies leading some governments to regulate discharges of pesticides under pollution discharge permits. The dual registration and discharge permitting provisions are burdensome. In the United States, agricultural interest groups are advancing new legislation that would exempt pesticide residues from water permitting requirements. An analysis of the dangers posed by pesticide residues in drinking water leads to a conclusion that both pesticide registration and pollutant discharge permitting provisions are needed to protect human health and aquatic species. PMID:24814945

  9. Requiring pollutant discharge permits for pesticide applications that deposit residues in surface waters.

    PubMed

    Centner, Terence; Eberhart, Nicholas

    2014-05-01

    Agricultural producers and public health authorities apply pesticides to control pests that damage crops and carry diseases. Due to the toxic nature of most pesticides, they are regulated by governments. Regulatory provisions require pesticides to be registered and restrictions operate to safeguard human health and the environment. Yet pesticides used near surface waters pose dangers to non-target species and drinking water supplies leading some governments to regulate discharges of pesticides under pollution discharge permits. The dual registration and discharge permitting provisions are burdensome. In the United States, agricultural interest groups are advancing new legislation that would exempt pesticide residues from water permitting requirements. An analysis of the dangers posed by pesticide residues in drinking water leads to a conclusion that both pesticide registration and pollutant discharge permitting provisions are needed to protect human health and aquatic species. PMID:24814945

  10. THE RECOGNITION OF DIAZINON, AN ORGANOPHOSPHORUS PESTICIDE, WHEN FOUND IN SAMPLES IN THE FORM OF DECOMPOSITION PRODUCTS

    EPA Science Inventory

    The contents of a bottle, from which a human being was reported to have drunk and which were believed responsible to an organophosphorus poisoning, were submitted for chemical analysis. Initial screening by gas chromatography with phosphorus, sulfur and nitrogen specific detector...

  11. An application of new microwave absorption tube in non-polar solvent microwave-assisted extraction of organophosphorus pesticides from fresh vegetable samples.

    PubMed

    Zhao, Xin; Xu, Xu; Su, Rui; Zhang, Hanqi; Wang, Ziming

    2012-03-16

    A new self-designed microwave absorption tube was used in microwave-assisted extraction of seven organophosphorus pesticides from four kinds of vegetable samples. The non-polar solvent was used as extraction solvent, and a new portable microwave extraction apparatus was used. By sealing graphite powder in glass tube, microwave absorption tube was made and used to heat samples directly. The extracts were directly analyzed by GC-MS without any clean-up process. The effects of some experimental parameters on extraction efficiency were investigated and optimized. 3.0 g of sample, 25 mL of hexane and three microwave absorption tubes were added in the microwave extraction vessel, the extraction was carried out under 425 W irradiation power at 70 °C for 8 min. The recoveries were in the range of 76.5-109.4% and the relative standard deviations were lower than 13.1%. PMID:22321952

  12. Effect of handling and processing on pesticide residues in food- a review.

    PubMed

    Bajwa, Usha; Sandhu, Kulwant Singh

    2014-02-01

    Pesticides are one of the major inputs used for increasing agricultural productivity of crops. The pesticide residues, left to variable extent in the food materials after harvesting, are beyond the control of consumer and have deleterious effect on human health. The presence of pesticide residues is a major bottleneck in the international trade of food commodities. The localization of pesticides in foods varies with the nature of pesticide molecule, type and portion of food material and environmental factors. The food crops treated with pesticides invariably contain unpredictable amount of these chemicals, therefore, it becomes imperative to find out some alternatives for decontamination of foods. The washing with water or soaking in solutions of salt and some chemicals e.g. chlorine, chlorine dioxide, hydrogen peroxide, ozone, acetic acid, hydroxy peracetic acid, iprodione and detergents are reported to be highly effective in reducing the level of pesticides. Preparatory steps like peeling, trimming etc. remove the residues from outer portions. Various thermal processing treatments like pasteurization, blanching, boiling, cooking, steaming, canning, scrambling etc. have been found valuable in degradation of various pesticides depending upon the type of pesticide and length of treatment. Preservation techniques like drying or dehydration and concentration increase the pesticide content many folds due to concentration effect. Many other techniques like refining, fermentation and curing have been reported to affect the pesticide level in foods to varied extent. Milling, baking, wine making, malting and brewing resulted in lowering of pesticide residue level in the end products. Post harvest treatments and cold storage have also been found effective. Many of the decontamination techniques bring down the concentration of pesticides below MRL. However, the diminution effect depends upon the initial concentration at the time of harvest, substrate/food and type of

  13. Sol-gel/nanoclay composite as a solid-phase microextraction fiber coating for the determination of organophosphorus pesticides in water samples.

    PubMed

    Saraji, Mohammad; Jafari, Mohammad Taghi; Sherafatmand, Hossein

    2015-02-01

    A novel solid-phase microextraction (SPME) fiber coated with a sol-gel/nanoclay composite was prepared by the sol-gel technique involving the hydrolysis reaction of alkoxysilanes and the subsequent condensation reaction with hydroxyl groups of the nanoclay on a stainless steel wire. A method based on direct immersion SPME and gas chromatography-corona discharge ion mobility spectrometry was developed for the determination of four organophosphorus pesticides in aqueous samples. The effect of different experimental parameters on the extraction efficiency of the method was investigated. The sol-gel/nanoclay fiber showed higher extraction performance for the organophosphorus pesticides compared with Ppy/nanoclay, sol-gel coating, and three commercial fibers (polydimethylsiloxane (PDMS), PDMS/divinylbenzene (DVB), and polyacrylate (PA)). Limits of detection (LOD) and quantitation (LOQ) of the method were in the range of 0.003-0.012 and 0.01-0.02 μg L(-1), respectively. The calibration curves were linear in a concentration range from 0.01 to 2.0 μg L(-1) (r (2)  > 0.995). The relative standard deviations for intra- and inter-day precision were 3.3-5.6 and 6.4-8.4 %, respectively. Fiber-to-fiber reproducibility for three prepared fibers was 7.4-10.2 %. Finally, the method was successfully applied for the extraction of the studied compounds from water samples. The relative recovery obtained for the spiked real-water samples were 86-104 %. PMID:25471290

  14. Influence of pesticide residues on honey bee (Hymenoptera: Apidae) colony health in France.

    PubMed

    Chauzat, Marie-Pierre; Carpentier, Patrice; Martel, Anne-Claire; Bougeard, Stéphanie; Cougoule, Nicolas; Porta, Philippe; Lachaize, Julie; Madec, François; Aubert, Michel; Faucon, Jean-Paul

    2009-06-01

    A 3-yr field survey was carried out in France, from 2002 to 2005, to study honey bee (Apis mellifera L.) colony health in relation to pesticide residues found in the colonies. This study was motivated by recent massive losses of honey bee colonies, and our objective was to examine the possible relationship between low levels of pesticide residues in apicultural matrices (honey, pollen collected by honey bees, beeswax) and colony health as measured by colony mortality and adult and brood population abundance. When all apicultural matrices were pooled together, the number of pesticide residue detected per sampling period (four sampling periods per year) and per apiary ranged from 0 to 9, with the most frequent being two (29.6%). No pesticide residues were detected during 12.7% of the sampling periods. Residues of imidacloprid and 6- chloronicotinic acid were the most frequently detected in pollen loads, honey, and honey bee matrices. Several pairs of active ingredients were present concurrently within honey bees and in pollen loads but not in beeswax and honey samples. No statistical relationship was found between colony mortality and pesticide residues. When pesticide residues from all matrices were pooled together, a mixed model analysis did not show a significant relationship between the presence of pesticide residues and the abundance of brood and adults, and no statistical relationship was found between colony mortality and pesticide residues. Thus, although certain pesticide residues were detected in apicultural matrices and occasionally with another pesticide residual, more work is needed to determine the role these residues play in affecting colony health. PMID:19508759

  15. Three years monitoring survey of pesticide residues in Sardinia wines following integrated pest management strategies.

    PubMed

    Angioni, Alberto; Dedola, Fabrizio

    2013-05-01

    This paper reports the results of a pesticide monitoring survey on wine grapes from the 2008-2010 vintage from vineyards grown according to integrated pest management strategies. A multi-residue gas chromatography-mass spectrometry method in electron ionization and chemical ionization mode has been used for the determination of 30 pesticides in wine samples. The analytical method showed good recoveries and allowed a good separation of the selected pesticides. Repeatability and intermediate precision showed good results with CV < 20 %. The instrumental method limits of determination (LOD) and of quantification (LOQ) were below the maximum residue levels set in wine. The analysis of the wines showed that pesticide residues were below the instrumental LOQ, and most of them were undetectable (pesticide applied has been detected in at least one cultivar. Metalaxil, myclobutanil, and penconazole were the pesticides most frequently found, while carignano and vermentino were the cultivars with the higher number of residues. PMID:22976121

  16. Organophosphorus (OP) Pesticide Degradation in the Presence of Chlorinated Oxidants: Kinetics, Modeling, and Structure-Activity Relationships

    EPA Science Inventory

    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...

  17. Health risk for children and adults consuming apples with pesticide residue.

    PubMed

    Lozowicka, Bozena

    2015-01-01

    The presence of pesticide residues in apples raises serious health concerns, especially when the fresh fruits are consumed by children, particularly vulnerable to the pesticide hazards. This study demonstrates the results from nine years of investigation (2005-2013) of 696 samples of Polish apples for 182 pesticides using gas and liquid chromatography and spectrophotometric techniques. Only 33.5% of the samples did not contain residues above the limit of detection. In 66.5% of the samples, 34 pesticides were detected, of which maximum residue level (MRL) was exceeded in 3%. Multiple residues were present in 35% of the samples with two to six pesticides, and one sample contained seven compounds. A study of the health risk for children, adults and the general population consuming apples with these pesticides was performed. The pesticide residue data have been combined with the consumption of apples in the 97.5 percentile and the mean diet. A deterministic model was used to assess the chronic and acute exposures that are based on the average and high concentrations of residues. Additionally, the "worst-case scenario" and "optimistic case scenario" were used to assess the chronic risk. In certain cases, the total dietary pesticide intake calculated from the residue levels observed in apples exceeds the toxicological criteria. Children were the group most exposed to the pesticides, and the greatest short-term hazard stemmed from flusilazole at 624%, dimethoate at 312%, tebuconazole at 173%, and chlorpyrifos methyl and captan with 104% Acute Reference Dose (ARfD) each. In the cumulative chronic exposure, among the 17 groups of compounds studied, organophosphate insecticides constituted 99% acceptable daily intake (ADI). The results indicate that the occurrence of pesticide residues in apples could not be considered a serious public health problem. Nevertheless, an investigation into continuous monitoring and tighter regulation of pesticide residues is recommended. PMID

  18. Distribution of pesticide residues within homes in central New York State.

    PubMed

    Obendorf, S K; Lemley, A T; Hedge, A; Kline, A A; Tan, K; Dokuchayeva, T

    2006-01-01

    Residues for 17 pesticides were analyzed in 41 households in central New York State that represented farm, rural, and urban houses. Samples were taken in both summer and winter of 2000-2001 from the same households from four locations; family room carpet; adjacent smooth floor; flat tabletop surface; and settled dust collected in a Petri dish on a tabletop. Pesticide residues were analyzed to identity factors that influence both the transport into and the redistribution of pesticides in the indoor environment. Differences were observed between the various pesticides and pesticide classifications relative to location within and between households as well as by season. Variations in the pesticide residues were related to a number of factors. Higher residues were observed in the farm households, particularly in summer, with the highest amount observed for chloropyrifos in carpet (33 microg/m2). For many pesticides, the frequency of detection and the amount of residues were higher in summer, which relates to usage patterns in agriculture and horticulture; however, larger amounts of insecticides such as mecoprop, resmethrin, and tetramethrin were found on flat surfaces in winter, indicating household use and possible redistribution within the home. Distribution patterns suggest that routines within a household may cause high variation in residues; these practices include indoor pets and treatment for fleas and ticks, use of termiticides, and fastidiousness of occupants. Frequency of pesticide detection was highest in carpet for both summer and winter for all households, indicating that carpets hold pesticides over time. Adsorbent fibrous materials such as textiles hold pesticides by macro- and micro-occlusion in their complex structures. Amounts of pesticide residue were higher in carpets than on smooth floors, particularly for rural farm households where the farmer was a certified pesticide applicator. The maximum amount of pesticide residue on a smooth floor surface

  19. Investigation of pesticide residues in vegetables and fruits grown in various regions of Hatay, Turkey.

    PubMed

    Sungur, Sana; Tunur, Cetin

    2012-01-01

    In this study, 175 pesticide residues in various vegetable and fruit samples grown in different regions of Hatay, Turkey, were investigated. Residue analyses were performed using liquid chromatography-tandem mass spectrometry with the QuEChERS method. In tomato, plum and apricot samples, pesticide residues were below the limits of detection. In other samples, at least one pesticide residue was detected. Twelve pesticides (acetamiprid, carbendazim, chlorpyrifos, fenarimol, fludioxonil, hexythiazox, imidacloprid, metalaxyl, pyridaben, pyriproxyfen, thiabendozole, triadimenol) were found at levels between 0.003 and 0.759 mg kg(-1). Only in cucumber samples, acetamiprid residues were found at levels greater than the maximum acceptable limit in Turkish Food Codex and European Union maximum residue limits (EU MRLs). In other samples, the detected residue amounts are less than the MRLs declared in the Turkish Food Codex and EU MRLs. PMID:24786407

  20. Analysis of pesticides residues in environmental water samples using multiwalled carbon nanotubes dispersive solid-phase extraction.

    PubMed

    González-Curbelo, Miguel Ángel; Herrera-Herrera, Antonio V; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel

    2013-02-01

    In this manuscript, a dispersive SPE method based on the use of multiwalled carbon nanotubes has been developed for the determination of 15 organophosphorus pesticides residues including some of their metabolites (disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, disulfoton sulfone, and fensulfothion) from real environmental waters (run-off, mineral and tap water) by GC with nitrogen phosphorus detection. Factors that affect the enrichment efficiency such as sample volume, multiwalled carbon nanotubes amount, and volume of eluent were studied. The optimized method was validated in terms of matrix-matched calibration, recovery, precision, and accuracy for the three analyzed samples. In this last case, the developed Student's t test demonstrated that there were no significant differences between real and spiked concentrations. Optimum dispersive SPE conditions (extraction of 200 mL of water, pH 6.0, with 130 mg of multiwalled carbon nanotubes, elution with 25 mL of dichloromethane for run-off and tap water and 30 mL for mineral water) allowed the quantitative extraction of analytes at levels lower than the maximum residues limits legislated by the European Union, with LODs between 1.16 and 93.6 ng/L. Absolute recovery values achieved were in the range of 67-107% (RSD values <10.1%). PMID:23303564

  1. Pesticides

    MedlinePlus

    ... ACMT Recognition Awards Annual Scientific Meeting Travel Scholarships Pesticides Public Health > Public > Toxicology FAQ's > Pesticides Pesticides What are pesticides ? How do pesticides work ? How ...

  2. Acute intake assessment: evolution within the Codex Committee on Pesticide Residues. WHO Joint Secretary of the Joint FAO/WHO meeting on pesticide residues JMPR.

    PubMed

    Herrman, J L

    2000-07-01

    The Codex Committee on Pesticide Residues (CCPR), in its development of international standards, has been considering during the last few years the implications of residues of acutely toxic pesticides in food commodities. CCPR has asked its scientific advisory body, the Joint FAO/WHO Meeting on Pesticide Residues (JMPR), for advice on the safety of the standards that are being developed. This work began in 1993. The 1994 JMPR first decided to use the 'acute reference dose' as a toxicological benchmark for a 'short-term ADI'. A number of acute reference doses have been allocated at subsequent meetings. The 1998 JMPR decided to consider the allocation of an acute reference dose whenever a full evaluation of a pesticide is undertaken. General guidance for the allocation of an acute reference dose was provided by the 1998 JMPR, which is discussed in this paper. PMID:10983577

  3. A survey of organochlorine pesticide residues in cheese samples from three Mexican regions.

    PubMed

    Albert, L A; Alpuche, L; Bárcenas, C; Rendón, J

    1990-01-01

    Organochlorine pesticide residues were determined in cheese samples from three Mexican regions. All samples were found to be contaminated by these residues: p,p'-DDE was present in 100% of the samples. Other pesticides found with high frequencies were HCB, three of the BHC isomers, as well as heptachlor and its epoxide. Also found, although less frequently, were residues of p,p'-DDD, p,p'-DDT, aldrin, dieldrin and endrin. Samples from the region known as Comarca Lagunera had the highest number of pesticides per sample. The highest concentrations of residues were found in cheese samples from the Soconusco and the Comarca Lagunera regions. PMID:15092270

  4. 7 CFR 29.425 - Submission and disposition of pesticide residues and end user(s) certification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Submission and disposition of pesticide residues and... Miscellaneous § 29.425 Submission and disposition of pesticide residues and end user(s) certification. (a) Completion of certification: The importer shall complete a pesticide residue and end user(s) certification...

  5. 7 CFR 29.425 - Submission and disposition of pesticide residues and end user(s) certification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Submission and disposition of pesticide residues and... Miscellaneous § 29.425 Submission and disposition of pesticide residues and end user(s) certification. (a) Completion of certification: The importer shall complete a pesticide residue and end user(s) certification...

  6. 7 CFR 29.425 - Submission and disposition of pesticide residues and end user(s) certification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Submission and disposition of pesticide residues and... Miscellaneous § 29.425 Submission and disposition of pesticide residues and end user(s) certification. (a) Completion of certification: The importer shall complete a pesticide residue and end user(s) certification...

  7. 7 CFR 29.425 - Submission and disposition of pesticide residues and end user(s) certification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Submission and disposition of pesticide residues and... Miscellaneous § 29.425 Submission and disposition of pesticide residues and end user(s) certification. (a) Completion of certification: The importer shall complete a pesticide residue and end user(s) certification...

  8. 7 CFR 29.425 - Submission and disposition of pesticide residues and end user(s) certification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Submission and disposition of pesticide residues and... Miscellaneous § 29.425 Submission and disposition of pesticide residues and end user(s) certification. (a) Completion of certification: The importer shall complete a pesticide residue and end user(s) certification...

  9. Distribution of multiple pesticide residues in apple segments after home processing.

    PubMed

    Rasmusssen, R R; Poulsen, M E; Hansen, H C B

    2003-11-01

    The effects of washing, storing, boiling, peeling, coring and juicing on pesticide residue were investigated for field-sprayed Discovery and Jonagold apples. Residues of chlorpyrifos, cypermethrin, deltamethrin, diazinon, endosulfan, endosulfan sulfate, fenitrothion, fenpropathrin, iprodione, kresoxim-methyl, lambda-cyhalothrin, quinalphos, tolylfluanid and vinclozolin in the processed apples were analysed by gas chromatography. Statistical analysis showed that reductions of 18-38% were required to obtain significant effects of processing practices, depending on pesticide and apple variety. Juicing and peeling the apples significantly reduced all pesticide residues. In the case of detectable pesticide residues, 1-24% were distributed in the juice and in the peeled apple. None of the pesticide residues was significantly reduced when the apples were subject to simple washing or coring. Storing significantly reduced five of the pesticide residues: diazinon, chlorpyrifos, fenitrothion, kresoxim-methyl and tolylfluanid, by 25-69%. Residues of the metabolite endosulfan sulfate were increased by 34% during storage. Boiling significantly reduced residues of fenitrothion and tolylfluanid by 32 and 81%, respectively. Only a few of the observed effects of processing could be explained by the physical or chemical characteristics of the pesticides. No differences in effect of processing due to apple variety were identified. PMID:14668155

  10. In vitro skin permeation and decontamination of the organophosphorus pesticide paraoxon under various physical conditions--evidence for a wash-in effect.

    PubMed

    Misik, Jan; Pavlikova, Ruzena; Josse, Denis; Cabal, Jiri; Kuca, Kamil

    2012-09-01

    Misuse of various chemicals, such as chemical warfare agents, industrial chemicals or pesticides during warfare or terrorists attacks requires adequate protection. Thus, development and evaluation of novel decontamination dispositives and techniques are needed. In this study, in vitro permeation and decontamination of a potentially hazardous compound paraoxon, an active metabolite of organophosphorus pesticide parathion, was investigated. Skin permeation and decontamination experiments were carried out in modified Franz diffusion cells. Pig skin was used as a human skin model. Commercially produced detergent-based washing solutions FloraFree(™) and ArgosTM were used as decontamination means. The experiments were done under "warm", "cold", "dry" and "wet" skin conditions in order to determine an effect of various physical conditions on skin permeation of paraoxon and on a subsequent decontamination process. There was no significant difference in skin permeation of paraoxon under warm, cold and dry conditions, whereas wet conditions provided significantly higher permeation rates. In the selected conditions, decontamination treatments performed 1 h after a skin exposure did not decrease the agent volume that permeated through the skin. An exception were wet skin conditions with non-significant decontamination efficacy 18 and 28% for the FloraFree(™) and Argos(™) treatment, respectively. In contrast, the skin permeation of paraoxon under warm, cold and dry conditions increased up to 60-290% following decontamination compared to non-decontaminated controls. This has previously been described as a skin wash-in effect. PMID:22519880

  11. Pesticide residues in fruits and vegetables from the Aegean region, Turkey.

    PubMed

    Bakırcı, Gözde Türköz; Yaman Acay, Dilek Bengü; Bakırcı, Fatih; Ötleş, Semih

    2014-10-01

    The purpose of this study was to investigate pesticide residues in fruits and vegetables from the Aegean region of Turkey. A total of 1423 samples of fresh fruit and vegetables were collected from 2010 to 2012. The samples were analysed to determine the concentrations of 186 pesticide residues. The analyses utilized ultrahigh performance liquid chromatography coupled with tandem mass spectrometry (UPLC/MS/MS) and gas chromatography with an electron capture detector (GC-ECD) confirmed by gas chromatography with mass spectrometry (GC-MS) after a multi-residue extraction procedure (the QuEChERS method). The results were evaluated according to maximum residue limits (MRLs) for each commodity and pesticide by Turkish Regulation. All pomegranate, cauliflower and cabbage samples were pesticides-free. A total of 754 samples contained detectable residues at or below MRLs, and 48 (8.4%) of the fruit samples and 83 (9.8%) of the vegetable samples contained pesticide residues above MRLs. MRL values were most often exceeded in arugula, cucumber, lemon, and grape commodities. All detected pesticides in apricot, carrot, kiwifruit and leek were below the MRLs. Acetamiprid, chlorpyriphos and carbendazim were the most detected pesticide residues. PMID:24799252

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    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, <0.1 μg/l) to 33.41 μg/l in the tested samples. Parathion was found in two tested samples at the concentration of 0.73 and 6.23 μg/l. None of the tested samples was found contaminated with Methoxychlor, DDT and Ethion. Three soil bacterial isolates, Pseudomonas peli BG1, Burkholderia caryophylli BG4 and Brevundimonas diminuta PD6 degraded chlorpyrifos completely in 8, 10 and 10 days, respectively, when 20 mg/l chlorpyrifos was supplied as sole source of carbon. Whereas, BG1, BG4 and PD6 took 14, 16 and 16 days, respectively, for complete removal of 50 mg/l chlorpyrifos. Chlorpyrifos degradation rates were found maximum by all three isolates at 2nd day of incubation for both tested concentrations. The results of the present study suggest the need for regular monitoring of 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.

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

    NASA Astrophysics Data System (ADS)

    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, <0.1 μg/l) to 33.41 μg/l in the tested samples. Parathion was found in two tested samples at the concentration of 0.73 and 6.23 μg/l. None of the tested samples was found contaminated with Methoxychlor, DDT and Ethion. Three soil bacterial isolates, Pseudomonas peli BG1, Burkholderia caryophylli BG4 and Brevundimonas diminuta PD6 degraded chlorpyrifos completely in 8, 10 and 10 days, respectively, when 20 mg/l chlorpyrifos was supplied as sole source of carbon. Whereas, BG1, BG4 and PD6 took 14, 16 and 16 days, respectively, for complete removal of 50 mg/l chlorpyrifos. Chlorpyrifos degradation rates were found maximum by all three isolates at 2nd day of incubation for both tested concentrations. The results of the present study suggest the need for regular monitoring of 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.

  14. Decontamination of spills and residues of some pesticides and of protective clothing worn during the handling of the pesticides

    SciTech Connect

    Armour, M.A.; Nelson, C.; Sather, P. Briker, Y.

    1996-12-31

    Users of pesticides may have waste or surplus quantities or spills for disposal. One alternative is to deactivate the pesticide at the handling site by using a straightforward chemical reaction. This option can be practical for those who use relatively small quantities of a large variety of pesticides, for example, greenhouse workers, small farmers, and agricultural researchers. This paper describes practical on-site methods for the disposal of spills or small waste quantities of five commonly used pesticides, Diazinon, Chlorpyrifos, Iprodione, 2,4-D, and Captan. These have been tested in the laboratory for the rate of disappearance of the pesticide, the degree of conversion to nontoxic products, the nature and identity of the products, the practicality of the method, and the ease of reproducibility. Methods selected were shown to be safe for the operator, reliable, and reproducible. Greater than 99% of the starting material had to be reacted under reasonable conditions and length of time. Detailed descriptions of the reactions are presented, so that they can be performed with reproducible results. Protective clothing worn during the handling and application of pesticides may become contaminated. Simple laundering does not always remove all of the pesticide residues. Thus, chronic dermal exposure may result from the pesticide-contaminated clothing. Appropriate methods of laundering using specific pretreatments have been determined. 7 refs.

  15. Multi pesticide and PCB residues in Nile tilapia and catfish in Assiut city, Egypt.

    PubMed

    Yahia, Doha; Elsharkawy, Eman E

    2014-01-01

    The current study investigated the levels of multi pesticide residues in the highly consumed types of Nile fish in Egypt: tilapia and cat fish. A total of 50 Nile tilapia (Oreochromis niloticus) and 50 African catfish (Clarias gariepinus) were collected from two areas in Assiut city, where most industries are situated and where agricultural activities and raising of farm animals are the main activities. In the first area, Elwasta, there is an electrical power station, and the second area, Mankbad, there is a cement factory. Fish samples were analyzed by High Resolution Gas Chromatography/Mass Spectrometry. Average pesticide residue concentrations±SE in muscle of tilapia and catfish (n = 10 pooled samples with five fish each) were determined. The results indicated the presence of different types of organophosphorous (OPs), organochlorine (OC), polychlorinated biphenyles (PCBs), hexachlorobenzene (HCB) and trifluralin pesticides in Elwasta and Mankbad in varying degrees. Diazenon was the only OP pesticide which exceeded the permissible limit in both investigated areas with the two types of fish. On the other hand, OCs, PCBs, HCB and trifluralin pesticide residue levels have not exceeded the maximum allowable concentration limit. In general, a higher pesticide residue level was obtained in Mankbad than Elwasta. In addition, higher values are realized for the detected pesticide residues in cat fish than tilapia. The results of the study have shown the extensive and recent use of these types of pesticides in the present time in Egypt. PMID:23911921

  16. Determination of some organochlorine pesticide residues in honeys from Konya, Turkey.

    PubMed

    Yavuz, Halil; Guler, Gokalp O; Aktumsek, Abdurrahman; Cakmak, Yavuz S; Ozparlak, Haluk

    2010-09-01

    In this study, 24 organochlorine pesticide residues in 109 different honey samples collected from stores and open markets in Konya, Turkey were analyzed by gas chromatography-electron capture detection. Aldrin, cis-chlordane, trans-chlordane, oxy-chlordane, 2,4(')-DDE, and 4,4(')-DDE were found in all honey samples. The mean value was 0.0540 microg g(-1) for oxy-chlordane. In the 55 samples of 109, levels of organochlorine pesticide residues of oxy-chlordane were determined as higher than those of Turkish Alimentarius Codex maximum residual limits (MRLs). Other organochlorine pesticide residues also exceeded MRLs except for cis-heptachlor epoxide and alpha-hexachlorocyclohexane. Since all of the honey samples are found contaminated and most of these samples exceeded MRLs, a control of organochlorine pesticide residues in honey is necessary for consumer health. PMID:19685151

  17. Trace level determination of organochlorine, organophosphorus and pyrethroid pesticides in lanolin using gel permeation chromatography followed by dual gas chromatography and gas chromatography-negative chemical ionization mass spectrometric confirmation.

    PubMed

    Jover, Eric; Bayona, Josep Maria

    2002-03-15

    A methodology for multi-class pesticide determination at trace level in lanolin is presented. Gel permeation chromatography on a Bio-Beads SX-3 column followed by a dual GC chromatographic determination has been developed. The effluent of the analytical column (50% diphenyl-methyl- or 14% cyanopropyl-phenylpolysiloxane) was split into an electron-capture and a nitrogen-phosphorus detection system. The chromatographic system was optimised for 28 pesticides commonly used to control sheep pests and corresponding to organochlorine, organophosphorus and pyretroid classes. Identification has been carried out by gas chromatography coupled to negative chemical ionization mass spectrometry. Recoveries ranged from 72 to 94% and the detection limits from 20 to 97 ng/g depending on the pesticide class, the RSDs were below 10%. Finally, the developed analytical methodology has been successfully applied to the determination of pesticides in several lanolin samples. PMID:11990995

  18. Adverse effects of pesticides residues on biochemical markers in pakistani tobacco farmers.

    PubMed

    Khan, Dilshad A; Bhatti, Mahwish M; Khan, Farooq A; Naqvi, Syed T; Karam, A

    2008-01-01

    Tobacco is an important cash crop of Pakistan and tremendous amount of irrational pesticides are being used to control insect growth. The frequency of plasma pesticide residues above acceptable daily intake (ADI) and its correlation with biochemical markers for assessment of adverse health effects in the tobacco farmers at district Sawabi, Pakistan was determined. Total 109 adult males consisting of 55 tobacco farmers exposed to pesticides and 54 controls were included. Pesticides residues in blood were analyzed on HPLC and GC-NPD. Plasma butyrylcholinesterase (BChE) was analyzed by Ellman's method. Biochemical markers including serum calcium, phosphorus, urea, creatinine, bilirubin and liver enzymes were measured on Selectra-E auto analyzer. The tobacco farmers had multiple pesticides residues above ADI in their blood consisting of 35 (63%) methomyl; 31 (56%) thiodicarb; 34(62%) cypermethrin; 27 (49%) Imidacloprid; 18 (32%) Methamidophos and 15 (27%) endosulfan. BChE activity was significantly decreased in the pesticides exposed farmers as compared to controls (P<0.001). Plasma biochemical markers including ALT, AST, CK, LDH and phosphate were significantly raised in the pesticides exposed farmers as compared to control group (P<0.001). Total pesticides residues revealed a significant positive correlation with AST (r=0.42), LDH(r= 0.47), ALT (r=0.20) and phosphorus (r=0.51). Excessive exposure to pesticide caused cytotoxic changes in the hepatic and renal biochemical markers which were positively correlated with pesticide residue. Hence these biomarkers might be used in addition to BChE activity for monitoring of adverse effects of pesticides on the health of farm workers. PMID:19079663

  19. Adverse Effects of Pesticides Residues on Biochemical Markers in Pakistani Tobacco Farmers

    PubMed Central

    Khan, Dilshad A; Bhatti, Mahwish M; Khan, Farooq A; Naqvi, Syed T; Karam, A

    2008-01-01

    Tobacco is an important cash crop of Pakistan and tremendous amount of irrational pesticides are being used to control insect growth. The frequency of plasma pesticide residues above acceptable daily intake (ADI) and its correlation with biochemical markers for assessment of adverse health effects in the tobacco farmers at district Sawabi, Pakistan was determined. Total 109 adult males consisting of 55 tobacco farmers exposed to pesticides and 54 controls were included. Pesticides residues in blood were analyzed on HPLC and GC-NPD. Plasma butyrylcholinesterase (BChE) was analyzed by Ellman's method. Biochemical markers including serum calcium, phosphorus, urea, creatinine, bilirubin and liver enzymes were measured on Selectra-E auto analyzer. The tobacco farmers had multiple pesticides residues above ADI in their blood consisting of 35 (63%) methomyl; 31 (56%) thiodicarb; 34(62%) cypermethrin; 27 (49%) Imidacloprid; 18 (32%) Methamidophos and 15 (27%) endosulfan. BChE activity was significantly decreased in the pesticides exposed farmers as compared to controls (P<0.001). Plasma biochemical markers including ALT, AST, CK, LDH and phosphate were significantly raised in the pesticides exposed farmers as compared to control group (P<0.001). Total pesticides residues revealed a significant positive correlation with AST (r=0.42), LDH(r= 0.47), ALT (r=0.20) and phosphorus (r=0.51). Excessive exposure to pesticide caused cytotoxic changes in the hepatic and renal biochemical markers which were positively correlated with pesticide residue. Hence these biomarkers might be used in addition to BChE activity for monitoring of adverse effects of pesticides on the health of farm workers. PMID:19079663

  20. Environmental impact and remediation of residual lead and arsenic pesticides in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lead arsenate (PbHAsO4) was used as a pesticide for over 50 years in orchards throughout the world, and residual lead and arsenic have been found in high concentrations in these orchard soils long after the pesticide use ended. These high concentrations of lead and arsenic may create a potential ri...

  1. Sample preparation approaches for the analysis of pesticide residues in olives and olive oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural practices generally require the use of pesticides by olive growers for the best olive and olive oil production. Thus, analytical methods are needed to identify and quantify the pesticide residues that may be present, and ensure that the product complies with regulatory requirements. I...

  2. Comparison of Target and Non-target Mortality Rates from Residual Pesticide on HESCO Material

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We conducted a series of tests to determine if pesticides applied as persistent treatments (residual pesticides) to militarily relevant textile materials to kill mosquitoes, flies, and other disease and nuisance pests might also impact populations of beneficial insects. We exposed samples of pestic...

  3. MONITORING THE TRANSFER OF PESTICIDE RESIDUES FROM SOFT SURFACES TO FOODS

    EPA Science Inventory

    The Food Quality Protection Act of 1996 requires assessing pesticide residue exposures to children. Contact of soft surfaces by foods and the ingestion of the food represents a pesticide exposure pathway. Chlorpyrifos has widespread use indoors and would be protected from envir...

  4. Occurrence of non extractable pesticide residues in physical and chemical fractions of two soils

    NASA Astrophysics Data System (ADS)

    Andreou, Kostas; Semple, Kirk; Jones, Kevin

    2010-05-01

    Soils are considered to be a significant sink for organic contaminants, including pesticides, in the environment. Understanding the distribution and localisation of aged pesticide residues in soil is of great importance for assessing the mobility and availability of these chemicals in the environment. This study aimed to characterise the distribution of radiolabeled herbicide isoproturon and the radiolabeled insecticides diazinon and cypermethrin in two organically managed soils. The soils were spiked and aged under laboratory conditions for 17 months. The labile fraction of the pesticides residues was recovered in CaCl2 (0.01M) and then subjected to physical size fractionation using sedimentation and centrifugation steps, with >20μm, 20-2μm and 2-0.1μm soil factions collected. Further, the distribution of the pesticide residues in the organic matter of the fractionated soil was investigated using a sequential alkaline extraction (0.1N NaOH) into humic and fulvic acid and humin. Soil fractions of 20-2μm and 2-0.1μm had the largest burden of the 14C-residues. Different soil constituents have different capacities to form non-extractable residues. Soil solid fractions of 20-2 µm and <2 µm had far greater affinity to the 14C-pesticide residues than the coarser fraction (>20 µm). Fulvic acid showed to play a vital role in the formation and stabilisation of non-extractable 14C-pesticide residues in most cases.Assessment of the likelihood of the pesticide residues to become available to soil biota requires an understanding of the structure of the SOM matrix and the definition of the kinetics of the pesticide residues in different SOM pools as a function of the time.

  5. Assessing Children’s Dietary Pesticide Exposure: Direct Measurement of Pesticide Residues in 24-Hr Duplicate Food Samples

    PubMed Central

    Lu, Chensheng; Schenck, Frank J.; Pearson, Melanie A.; Wong, Jon W.

    2010-01-01

    Background The data presented here are a response to calls for more direct measurements of pesticide residues in foods consumed by children and provide an opportunity to compare direct measures of pesticide residues in foods representing actual consumption with those reported by the U.S. Department of Agriculture Pesticide Data Program. Objective We measured pesticide residues in 24-hr duplicate food samples collected from a group of 46 young children participating in the Children’s Pesticide Exposure Study (CPES). Methods Parents were instructed to collect 24-hr duplicate food samples of all conventional fruits, vegetables, and fruit juices equal to the quantity consumed by their children, similarly prewashed/prepared, and from the same source or batch. Individual or composite food items were analyzed for organophosphate (OP) and pyrethroid insecticide residues. Results We collected a total of 239 24-hr duplicate food samples collected from the 46 CPES children. We found 14% or 5% of those food samples contained at least one OP or pyrethroid insecticide, respectively. We measured a total of 11 OP insecticides, at levels ranging from 1 to 387 ng/g, and three pyrethroid insecticides, at levels ranging from 2 to 1,133 ng/g, in children’s food samples. We found that many of the food items consumed by the CPES children were also on the list of the most contaminated food commodities reported by the Environmental Working Group. Conclusions The frequent consumption of food commodities with episodic presence of pesticide residues that are suspected to cause developmental and neurological effects in young children supports the need for further mitigation. PMID:20639183

  6. STUDY TO IDENTIFY IMPORTANT PARAMETERS FOR CHARACTERIZING PESTICIDE RESIDUE TRANSFER EFFICIENCIES

    EPA Science Inventory

    To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for...

  7. 40 CFR 180.7 - Petitions proposing tolerances or exemptions for pesticide residues in or on raw agricultural...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... exemptions for pesticide residues in or on raw agricultural commodities or processed foods. 180.7 Section 180.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  8. 40 CFR 180.7 - Petitions proposing tolerances or exemptions for pesticide residues in or on raw agricultural...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... exemptions for pesticide residues in or on raw agricultural commodities or processed foods. 180.7 Section 180.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  9. 40 CFR 180.7 - Petitions proposing tolerances or exemptions for pesticide residues in or on raw agricultural...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... exemptions for pesticide residues in or on raw agricultural commodities or processed foods. 180.7 Section 180.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  10. 40 CFR 180.7 - Petitions proposing tolerances or exemptions for pesticide residues in or on raw agricultural...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... exemptions for pesticide residues in or on raw agricultural commodities or processed foods. 180.7 Section 180.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  11. 40 CFR 180.7 - Petitions proposing tolerances or exemptions for pesticide residues in or on raw agricultural...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... exemptions for pesticide residues in or on raw agricultural commodities or processed foods. 180.7 Section 180.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  12. Pesticide residue dynamics in passion fruits: comparing field trial and modelling results.

    PubMed

    Juraske, Ronnie; Fantke, Peter; Ramírez, Ana Cecilia Romero; González, Alonso

    2012-10-01

    We evaluated the exposure to pesticides from the consumption of passion fruits and subsequent human health risks by combining several methods: (i) experimental field studies including the determination of pesticide residues in/on passion fruits, (ii) dynamic plant uptake modelling, and (iii) human health risk assessment concepts. Eight commonly used pesticides were applied onto passion fruits cultivated in Colombia. Pesticide concentrations were measured periodically (between application and harvest) in whole fruits and fruit pulp. Measured concentrations were compared with predicted residues calculated with a dynamic and crop-specific pesticide uptake model, namely dynamiCROP. The model accounts for the time between pesticide application and harvest, the time between harvest and consumption, the amount of spray deposition on plant surfaces, uptake processes, dilution due to crop growth, degradation in plant components, and reduction due to food processing (peeling). Measured and modelled residues correspond well (r(2)=0.88-0.99), with all predictions falling within the 90% confidence interval of the measured values. A mean error of 43% over all studied pesticides was observed between model estimates and measurements. The fraction of pesticide applied during cultivation that is eventually ingested by humans is on average 10(-4)-10(-6), depending on the time period between application and ingestion and the processing step considered. Model calculations and intake fractions via fruit consumption based on experimental data corresponded well for all pesticides with a deviation of less than a factor of 2. Pesticide residues in fruits measured at recommended harvest dates were all below European Maximum Residue Limits (MRLs) and therefore do not indicate any violation of international regulatory thresholds. PMID:22673401

  13. Monitoring of some pesticides residue in consumed tea in Tehran market

    PubMed Central

    2013-01-01

    Tea is an agricultural product of the leaves, leaf buds, and internodes of various cultivars and sub-varieties of the Camellia sinensis plant, processed and vulcanized using various methods. Tea is a main beverage in Iranian food basket so should be free from toxic elements such as pesticides residue. There is no data bank on the residue of pesticides in the consumed black tea in Iran. The present study is the first attempt for monitoring of 25 pesticide residues from different chemical groups in tea samples obtained from local markets in Tehran, I.R. Iran during the period 2011. A reliable and accurate method based on spiked calibration curve and QuEChERS sample preparation was developed for determination of pesticide residues in tea by gas chromatography–mass spectrometry (GC/MS). The using of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects and negative recovery affected by GCB on pesticides. The recovery of pesticides at 3 concentration levels (n = 3) was in range of 81.4 - 99.4%. The method was proved to be repeatable with RSDr lower than 20%. The limits of quantification for all pesticides were ≤20 ng/g. 53 samples from 17 imported and manufactured brand were analyzed. Detectable pesticides residues were found in 28.3% (15 samples) of the samples. All of the positive samples were contaminated with unregulated pesticides (Endosulfan Sulfate or Bifenthrin) which are established by ISIRI. None of the samples had contamination higher than maximum residue limit set by EU and India. PMID:23369650

  14. Comparison of polyurethane foam and XAD-2 sampling matrices to measure airborne organophosphorus pesticides and their oxygen analogs in an agricultural community

    PubMed Central

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

    2013-01-01

    Side-by-side active air sampling for the organophosphorus (OP) pesticide, chlorpyrifos (CPF) and its oxygen analog, chlorpyrifos-oxon (CPF-O) was conducted with two recommended air sampling matrices: OSHA Versatile Sampling (OVS) tubes with XAD-2 resin, polyurethane foam (PUF) tubes, and passive PUF deposition disks. The study compared the proportion of artificially transformed CPF-O in the laboratory and in the field during a tree fruit application in Washington State. Lab results demonstrated that the NIOSH-recommended OVS tubes artificially transformed up to 32% of CPF to CPF-O during the sampling process, whereas PUF tubes had little to no artificial transformation (≤ 0.1%). In the field, the proportion of CPF-O in the sample was significantly higher on OVS tubes than on PUF tubes (p < 0.001), confirming that OVS tubes were converting a significant portion of CPF to CPF-O. In addition, PUF tubes reported measurable levels CPF-O in the field even when no artificial transformation was expected. We conclude that the PUF matrix is the superior sampling medium for OP oxygen analogs when compared to XAD-2 resin. Community-located PUF tube samples 24 hours post-application had considerably higher levels CPF-O (16–21 ng/m3) than near field samples during application (2–14 ng/m3), suggesting that the oxygen analog is volatile and formed during atmospheric transport. It is recommended that worker and community risk assessments begin to take into consideration the presence of the more toxic oxygen analogs when measuring for OP pesticide mixtures. PMID:23466277

  15. Comparison of polyurethane foam and XAD-2 sampling matrices to measure airborne organophosphorus pesticides and their oxygen analogs in an agricultural community.

    PubMed

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

    2013-07-01

    Side-by-side active air sampling for the organophosphorus (OP) pesticide, chlorpyrifos (CPF) and its oxygen analog, chlorpyrifos-oxon (CPF-O) was conducted with two recommended air sampling matrices: OSHA Versatile Sampling (OVS) tubes with XAD-2 resin, polyurethane foam (PUF) tubes, and passive PUF deposition disks. The study compared the proportion of artificially transformed CPF-O in the laboratory and in the field during a tree fruit application in Washington State. Lab results demonstrated that the NIOSH-recommended OVS tubes artificially transformed up to 32% of CPF to CPF-O during the sampling process, whereas PUF tubes had little to no artificial transformation (⩽0.1%). In the field, the proportion of CPF-O in the sample was significantly higher on OVS tubes than on PUF tubes (p<0.001), confirming that OVS tubes were converting a significant portion of CPF to CPF-O. In addition, PUF tubes reported measurable levels CPF-O in the field even when no artificial transformation was expected. We conclude that the PUF matrix is the superior sampling medium for OP oxygen analogs when compared to XAD-two resin. Community-located PUF tube samples 24h post-application had considerably higher levels CPF-O (16-21ngm(-3)) than near field samples during application (2-14ngm(-3)), suggesting that the oxygen analog is volatile and formed during atmospheric transport. It is recommended that worker and community risk assessments begin to take into consideration the presence of the more toxic oxygen analogs when measuring for OP pesticide mixtures. PMID:23466277

  16. Studies of pesticide residues in tomatoes and cucumbers from Kazakhstan and the associated health risks.

    PubMed

    Lozowicka, Bozena; Abzeitova, Elmira; Sagitov, Abai; Kaczynski, Piotr; Toleubayev, Kazbek; Li, Alina

    2015-10-01

    The aim of the present study was to assess the level of pesticide residues in vegetables in the Almaty Region of Kazakhstan and to determine the potential health risks associated with the exposures to these pesticides. A total of 82 samples of cucumbers and tomatoes from top agro-based market and greenhouses were analysed using a gas chromatography-micro electron capture detector/nitrogen-phosphorous detector (GC-μECD/NPD), a multiresidue method to analyse 184 different pesticide types. The results indicated that more than half of samples (59 %) contained 29 pesticides, in which 10 are not registered in Kazakhstan, ranging from 0.01 to 0.88 mg kg(-1), and 28 % contained pesticide residues above maximum residue levels (MRLs). The estimated daily intakes (EDIs) ranged from 0.01 % of the acceptable daily intake (ADI) for pyrimethanil to 12.05 % of the ADI for lambda-cyhalothrin. The most critical commodity is triazophos and flusilazole in tomatoes, contributing 70.8 and 42.5 % to the acute hazard index (aHI). The results provided important information on the current pesticide contamination status of two commonly consumed vegetables and pointed an urgent need to control the use of plant protection products applied, especially potentially persistent pesticides, such as endosulfan and dicofol. These results also show that the detected pesticides may be considered a public health problem. PMID:26337756

  17. Carbon nanotubes@silicon dioxide nanohybrids coating for solid-phase microextraction of organophosphorus pesticides followed by gas chromatography-corona discharge ion mobility spectrometric detection.

    PubMed

    Saraji, Mohammad; Jafari, Mohammad Taghi; Mossaddegh, Mehdi

    2016-01-15

    A high efficiency solid-phase microextraction (SPME) fiber coated with porous carbon nanotubes-silicon dioxide (CNTs-SiO2) nanohybrids was synthesized and applied for the determination of some organophosphorus pesticides (OPPs) in vegetables, fruits and water samples. Gas chromatography-corona discharge ion mobility spectrometry was used as the detection system. Glucose, as a biocompatible compound, was used for connecting CNT and SiO2 during a hydrothermal process. The electrospinning technique was also applied for the fiber preparation. The parameters affecting the efficiency of extraction, including stirring rate, salt effect, extraction temperature, extraction time, desorption temperature and desorption time, were investigated and optimized. The developed CNTs@SiO2 fiber presented better extraction efficiency than the commercial SPME fibers (PA, PDMS, and PDMS-DVB). The intra- and inter-day relative standard deviations were found to be lower than 6.2 and 9.0%, respectively. For water samples, the limits of detection were in the range of 0.005-0.020 μg L(-1) and the limits of quantification were between 0.010 and 0.050 μg L(-1). The results showed a good linearity in the range of 0.01-3.0 μg L(-1) for the analytes. The spiking recoveries ranged from 79 (± 9) to 99 (± 8). The method was successfully applied for the determination of OPPs in real samples. PMID:26709024

  18. Homogeneous Liquid-Liquid Microextraction for Determination of Organophosphorus Pesticides in Environmental Water Samples Prior to Gas Chromatography-Flame Photometric Detection.

    PubMed

    Berijani, Sana; Sadigh, Mirhanif; Pournamdari, Elham

    2016-07-01

    In this study, homogeneous liquid-liquid microextraction (HLLME) was developed for preconcentration and extraction of 15 organophosphorus pesticides (OPPs) from water samples coupling with gas chromatography followed by a flame photometric detector (HLLME-GC-FPD). In this method, OPPs were extracted by the homogeneous phase in a ternary solvent system (water/acetic acid/chloroform). The homogeneous solution was excluded by the addition of sodium hydroxide as a phase separator reagent and a cloudy solution was formed. After centrifugation (3 min at 5,000 rpm), the fine particles of extraction solvent (chloroform) were sedimented at the bottom of the conical test tube (10.0 ± 0.5 µL). Furthermore, 0.5 µL of the sedimented phase was injected into the GC for separation and determination of OPPs. Optimal results were obtained under the following conditions: volume of the extracting solvent (chloroform), 53 µL; volume of the consolute solvent (acetic acid), 0.76 mL and concentration of sodium hydroxide, 40% (w/v). Under the optimum conditions, the enrichment factors of (260-665), the extraction percent of 75.8-104%, the dynamic linear range of 0.03-300 µg L(-1) and the limits of detection of 0.004-0.03 µg L(-1) were obtained for the OPPs. This method was successfully applied for the extraction and determination of the OPPs in environmental water samples. PMID:26944949

  19. Sensitive fluorescence assay of organophosphorus pesticides based on the fluorescence resonance energy transfer between CdTe quantum dots and porphyrin.

    PubMed

    Xue, Gao; Yue, Zhao; Bing, Zhang; Yiwei, Tang; Xiuying, Liu; Jianrong, Li

    2016-08-01

    A sensitive and selective quantum dot (QD)-based fluorescence resonance energy transfer (FRET) biosensor was successfully fabricated for the detection of organophosphorus pesticides (OPs). 5,10,15,20-Tetra(4-pyridyl)porphyrin (TPyP) with meso-pyridyl substituents was bound to the surface of CdTe QDs to produce self-assembled nanosensors, and the process of FRET between QDs and TPyP occurred. However, the process of FRET was switched off with the addition of OPs, due to the combination between TPyP and OPs. The fluorescence intensity of TPyP (donor) would decrease gradually with the increasing concentration of OPs. Under optimal conditions, a linear correlation was established between the fluorescence intensity ratio ITPyP/IQDs and the concentration of paraoxon in the range of 9.09 × 10(-12)-1.09 × 10(-6) mol L(-1) with a detection limit of 3.15 × 10(-12) mol L(-1). The attractive sensitivity was obtained due to the efficient FRET and the superior fluorescence properties of QDs. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results. PMID:27305657

  20. Medium-assisted non-polar solvent dynamic microwave extraction for determination of organophosphorus pesticides in cereals using gas chromatography-mass spectrometry.

    PubMed

    Wu, Lijie; Song, Ying; Xu, Xu; Li, Na; Shao, Mingyuan; Zhang, Hanqi; Yu, Aimin; Yu, Cui; Ma, Qiang; Lu, Chunmei; Wang, Ziming

    2014-11-01

    A fast and green pretreatment method, medium-assisted non-polar solvent dynamic microwave extraction, was first applied to extract ten of organophosphorus pesticides (OPPs) from five cereal samples. Without adding any polar solvent, graphite powders (GP) were used as microwave absorption medium to transform microwave energy into heat energy. For recycling GP, an extractor was made by sealing GP inside the exterior tube of a glass sleeve. By dynamic microwave extraction using hexane as extraction solvent, ten OPPs could be extracted completely within 200s, and the extract was directly analysed by GC-MS without any clean-up process. The effects of some experimental parameters on extraction efficiency were investigated and optimised. Relative standard deviations of intra- and inter-day ranging from 1.02% to 5.32% were obtained. Five real samples were analysed, and the recoveries obtained were in the range of 73.2-99.8%, and the relative standard deviations were lower than 6.63%. PMID:24874384

  1. [Residual pesticide concentrations after processing various types of tea and tea infusions].

    PubMed

    Kondo, Takahide; Watanabe, Ayaka; Shitara, Hiroshi; Kaburagi, Yasuo; Shibata, Masahisa; Kanda, Noriko; Kurokawa, Chieko; Inoue, Yutaka; Miyazaki, Motonobu; Togawa, Masayuki; Ozawa, Akihito; Uchiyama, Toru; Koizumi, Yutaka; Nakamura, Yoriyuki; Masuda, Shuichi; Maitani, Tamio

    2013-01-01

    The effects of processing to produce various types of tea or infusion on the levels of pesticide residues in tea were investigated for three insecticides (chlorfenapyr, pyrimiphos-methyl, and clothianidin). Tea plants were sprayed with one of the three pesticides and cultivated under cover. The levels of pesticide residues in tea decreased after processing according to the time and temperature of heating, as well as fermentation. Although significant differences were not observed among the three pesticides in the ratio of decreased of pesticide concentration after processing to green tea, clothianidin, which is a neonicotinoid insecticide and has a lower log Pow value, tended to be transferred more than the other two insecticides into infusions. However, no significant difference in the ratios of clothianidin transferred to infusions was observed among green tea with three different leaf sizes. PMID:24025203

  2. Occurrence of pesticide non extractable residues in physical and chemical fractions from two natural soils.

    NASA Astrophysics Data System (ADS)

    Andreou, K.; Jones, K.; Semple, K.

    2009-04-01

    Distribution of pesticide non extractable residues resulted from the incubation of two natural soils with each of the isoproturon, diazinon and cypermethrin pesticide was assessed in this study. Pesticide non extractable residues distribution in soil physical and chemical fractions is known to ultimately affect their fate. This study aimed to address the fate and behaviour of the non extractable residues in the context of their association with soil physical and chemical fractions with varying properties and characteristics. Non extractable residues were formed from incubation of each pesticide in the two natural soils over a period of 24 months. Soils containing the non extractable residues were fractionated into three solid phase fractions using a physical fractionation procedure as follows: Sediment (SED, >20 μm), (II) Microaggregate (MA, 20-2 μm) and (III) Colloid phase (COL, 2-0.05 μm). Each soil fraction was then fractionated into organic carbon chemical fractionations as follows: Fulvic acid (FA), Humic acid (HA) and Humin (HM). Significant amount of the pesticides was lost during the incubation period. Enrichment factors for the organic carbon and the 14C-pesticide residues were higher in the MA and COL fraction rather than the SED fraction. Greater association and enrichment of the fulvic acid fraction of the organic carbon in the soil was observed. Non extractable residues at the FA fraction showed to diminish while in the HA fraction were increased with decreasing the fraction size. An appreciable amount of non extractable residues were located in the HM fraction but this was less than the amount recovered in the humic substances. Long term fate of pesticide non extractable residues in the soil structural components is important in order to assess any risk associated with them.

  3. Threshold conditions for integrated pest management models with pesticides that have residual effects.

    PubMed

    Tang, Sanyi; Liang, Juhua; Tan, Yuanshun; Cheke, Robert A

    2013-01-01

    Impulsive differential equations (hybrid dynamical systems) can provide a natural description of pulse-like actions such as when a pesticide kills a pest instantly. However, pesticides may have long-term residual effects, with some remaining active against pests for several weeks, months or years. Therefore, a more realistic method for modelling chemical control in such cases is to use continuous or piecewise-continuous periodic functions which affect growth rates. How to evaluate the effects of the duration of the pesticide residual effectiveness on successful pest control is key to the implementation of integrated pest management (IPM) in practice. To address these questions in detail, we have modelled IPM including residual effects of pesticides in terms of fixed pulse-type actions. The stability threshold conditions for pest eradication are given. Moreover, effects of the killing efficiency rate and the decay rate of the pesticide on the pest and on its natural enemies, the duration of residual effectiveness, the number of pesticide applications and the number of natural enemy releases on the threshold conditions are investigated with regard to the extent of depression or resurgence resulting from pulses of pesticide applications and predator releases. Latin Hypercube Sampling/Partial Rank Correlation uncertainty and sensitivity analysis techniques are employed to investigate the key control parameters which are most significantly related to threshold values. The findings combined with Volterra's principle confirm that when the pesticide has a strong effect on the natural enemies, repeated use of the same pesticide can result in target pest resurgence. The results also indicate that there exists an optimal number of pesticide applications which can suppress the pest most effectively, and this may help in the design of an optimal control strategy. PMID:22205243

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

    PubMed

    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

  5. Pesticide residues in raspberries (Rubus idaeus L.) and dietary risk assessment.

    PubMed

    Łozowicka, B; Kaczyński, P; Jankowska, M; Rutkowska, E; Hrynko, I

    2012-01-01

    The aim of this study was to evaluate the residues of 140 pesticides in raspberries from north-eastern Poland (2005-2010). Gas chromatography with electron capture detector (GC-ECD) and nitrogen phosphorous detector (GC-NPD) was used. Among the 128 samples, 66 (51.6%) were found to detect residues: 14.1% contained one pesticide and around 38% multiple pesticide residues. The most frequently detected were pyrimethanil residues (36.0%). Twenty-seven (21.1%) raspberry samples exceeded the maximum residue limits. The estimated daily intakes ranged from 0.003% to 3.183% of the acceptable daily intake (ADI) for adults 0.008% and 9.7% for toddlers, respectively. The most critical case is procymidone, the acute risk was 180.9% of acute reference dose (ARfD) for toddlers and for adults (83% of ARfD) which is high. PMID:24779781

  6. Production of apple-based baby food: changes in pesticide residues.

    PubMed

    Kovacova, Jana; Kocourek, Vladimir; Kohoutkova, Jana; Lansky, Miroslav; Hajslova, Jana

    2014-01-01

    Apples represent the main component of most fruit-based baby food products. Since not only fruit from organic farming, but also conventionally grown fruit is used for baby food production, the occurrence of pesticide residues in the final product is of high concern. To learn more about the fate of these hazardous compounds during processing of contaminated raw material, apples containing altogether 21 pesticide residues were used for preparation of a baby food purée both in the household and at industrial scale (in the baby food production facility). Within both studies, pesticide residues were determined in raw apples as well as in final products. Intermediate product and by-product were also analysed during the industrial process. Determination of residues was performed by a sensitive multi-detection analytical method based on liquid or gas chromatography coupled with mass spectrometry. The household procedure involved mainly the cooking of unpeeled apples, and the decrease of residues was not extensive enough for most of the studied pesticides; only residues of captan, dithianon and thiram dropped significantly (processing factors less than 0.04). On the other hand, changes in pesticide levels were substantial for all tested pesticides during apple processing in the industrial baby food production facility. The most important operation affecting the reduction of residues was removal of the by-products after pulping (rest of the peel, stem, pips etc.), while subsequent sterilisation has an insignificant effect. Also in this case, captan, dithianon and thiram were identified as pesticides with the most evident decrease of residues. PMID:24720736

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

    PubMed

    Ting, K C; Kho, P

    1991-01-01

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

  8. Inspection of pesticide residues on food by surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Shende, Chetan; Gift, Alan; Inscore, Frank; Maksymiuk, Paul; Farquharson, Stuart

    2004-03-01

    Modern agriculture depends on pesticides to curb infestations, increase crop yield and to produce the quantity and quality of food demanded by today's society. However, potential pesticide residue contamination of food is of critical concern to the food industry and the regulators responsible for health and safety. For example, many pesticides kill insects by attacking the central nervous system, and the use of these pesticides above the EPA set tolerance levels (from 0.1 to 50 ppm) could pose a threat to humans, in particular infants. Unfortunately, rapid, chemical analysis of pesticide residues is unavailable, and only a very small fraction of foods are inspected. The greatest concern is food imported from nations that simply ignore US regulations. In an effort to address this need, we have been developing a simple device to collect residues from food surfaces, perform a rapid chemical separation, and detect and identify pesticides by surface-enhanced Raman spectroscopy (SERS). Capillaries are coated with a metal-doped sol-gel that both separates chemicals and generates SER spectra when irradiated. SERS of pesticides at ppm concentrations, and a preliminary product to aid inspectors is presented.

  9. Pesticides residues in milks and feedstuff of farm animals drawn from Greece.

    PubMed

    Tsiplakou, E; Anagnostopoulos, C J; Liapis, K; Haroutounian, S A; Zervas, G

    2010-07-01

    The objective of this study was to investigate if milk from dairy sheep and goats, fed mainly with supplementary feed during the winter months, was contaminated with pesticides residues. Tauwo hundred milk samples from sheep and goats were collected from 10 farms of each animals. The sheep and goats farms were selected from those which represent common conventional production and feeding systems in Greece. Milk and feed samples (alfalfa hay, wheat straw, shrubs, pasture and concentrates) were taken from each farm to analyze for pesticides residues. The results showed that the summation operatorendosulfan was the main pesticide residue which was detected in all the concentrates samples at a mean concentration of 5.36 mgkg(-1), which is much higher from the maximum residue level (MRL). In addition, the summation operatorendosulfan was also detected in all the alfalfa hay samples but at a mean concentration of 0.10 mgkg(-1) which is lower than the MRL. The mean concentrations of endosulfan alpha and beta were 2.82 and 2.39 mgkg(-1) in the concentrates samples and 0.08 and 0.02 mgkg(-1) respectively in alfalfa hay samples. In the wheat straw, shrubs and pasture samples no pesticides residues were detected. No pesticide residues were also detected in milk samples of sheep and goats. Thus, this milk from the farms sampled presents no human health risks as far as the contaminants analyzed concerned. PMID:20537679

  10. A comparative study of allowable pesticide residue levels on produce in the United States

    PubMed Central

    2012-01-01

    Background The U.S. imports a substantial and increasing portion of its fruits and vegetables. The U.S. Food and Drug Administration currently inspects less than one percent of import shipments. While countries exporting to the U.S. are expected to comply with U.S. tolerances, including allowable pesticide residue levels, there is a low rate of import inspections and few other incentives for compliance. Methods This analysis estimates the quantity of excess pesticide residue that could enter the U.S. if exporters followed originating country requirements but not U.S. pesticide tolerances, for the top 20 imported produce items based on quantities imported and U.S. consumption levels. Pesticide health effects data are also shown. Results The model estimates that for the identified items, 120 439 kg of pesticides in excess of U.S. tolerances could potentially be imported to the U.S., in cases where U.S. regulations are more protective than those of originating countries. This figure is in addition to residues allowed on domestic produce. In the modeling, the top produce item, market, and pesticide of concern were oranges, Chile, and Zeta-Cypermethrin. Pesticides in this review are associated with health effects on 13 body systems, and some are associated with carcinogenic effects. Conclusions There is a critical information gap regarding pesticide residues on produce imported to the U.S. Without a more thorough sampling program, it is not possible accurately to characterize risks introduced by produce importation. The scenario presented herein relies on assumptions, and should be considered illustrative. The analysis highlights the need for additional investigation and resources for monitoring, enforcement, and other interventions, to improve import food safety and reduce pesticide exposures in originating countries. PMID:22293037

  11. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues relative to an unamended control soil was assessed using Lumbricus terrestris in 4-L soil microcos...

  12. Plant uptake of pesticides and human health: dynamic modeling of residues in wheat and ingestion intake.

    PubMed

    Fantke, Peter; Charles, Raphaël; de Alencastro, Luiz Felippe; Friedrich, Rainer; Jolliet, Olivier

    2011-11-01

    Human intake of pesticide residues from consumption of processed food plays an important role for evaluating current agricultural practice. We take advantage of latest developments in crop-specific plant uptake modeling and propose an innovative dynamic model to estimate pesticide residues in the wheat-environment system, dynamiCROP. We used this model to analyze uptake and translocation of pesticides in wheat after foliar spray application and subsequent intake fractions by humans. Based on the evolution of residues in edible parts of harvested wheat we predict that between 22 mg and 2.1 g per kg applied pesticide are taken in by humans via consumption of processed wheat products. Model results were compared with experimentally derived concentrations in wheat ears and with estimated intake via inhalation and ingestion caused by indirect emissions, i.e. the amount lost to the environment during pesticide application. Modeled and measured concentrations in wheat fitted very well and deviate from less than a factor 1.5 for chlorothalonil to a maximum factor 3 for tebuconazole. Main aspects influencing pesticide fate behavior are degradation half-life in plant and time between pesticide application and crop harvest, leading to variations in harvest fraction of at least three orders of magnitude. Food processing may further reduce residues by approximately 63%. Intake fractions from residues in sprayed wheat were up to four orders of magnitude higher than intake fractions estimated from indirect emissions, thereby demonstrating the importance of exposure from consumption of food crops after direct pesticide treatment. PMID:21955352

  13. Codex Committee on Pesticide Residues--a plan for improved participation by governments.

    PubMed

    Wessel, J R

    1992-10-01

    The Codex Committee on Pesticide Residues (CCPR), which is responsible for establishing maximum residue limits (MRLs) for pesticides on food, has a vital role in protecting the public health and facilitating international trade. Codex MRLs are based on scientific evaluations by expert panels that constitute the Joint FAO/WHO Meeting on Pesticide Residues (JMPR). These panelists estimate an acceptable daily intake for a pesticide and expected level of residue remaining in food when the pesticide is used according to good agricultural practice. The goals of the CCPR are not being fully achieved. Governments are generally not accepting Codex MRLs; instead, technical and procedural aspects of the JMPR and CCPR process are being criticized. The CCPR is responding to valid criticisms of the process; however, governments may still lack the will to seek harmonization of pesticide limits for food in international trade. Overcoming this problem will be difficult, but not impossible. A plan of action is proposed that allows countries to selectively accept Codex MRLs, increase the number of chemicals in the JMPR/CCPR system for evaluation, and be responsive to both their consumers and their food producers without compromising national health and safety standards and competitive trade advantages. PMID:1438994

  14. Increased occurrence of pesticide residues on crops grown in protected environments compared to crops grown in open field conditions.

    PubMed

    Allen, Gina; Halsall, Crispin J; Ukpebor, Justina; Paul, Nigel D; Ridall, Gareth; Wargent, Jason J

    2015-01-01

    Crops grown under plastic-clad structures or in greenhouses may be prone to an increased frequency of pesticide residue detections and higher concentrations of pesticides relative to equivalent crops grown in the open field. To test this we examined pesticide data for crops selected from the quarterly reports (2004-2009) of the UK's Pesticide Residue Committee. Five comparison crop pairs were identified whereby one crop of each pair was assumed to have been grown primarily under some form of physical protection ('protected') and the other grown primarily in open field conditions ('open'). For each pair, the number of detectable pesticide residues and the proportion of crop samples containing pesticides were statistically compared (n=100 s samples for each crop). The mean concentrations of selected photolabile pesticides were also compared. For the crop pairings of cabbage ('open') vs. lettuce ('protected') and 'berries' ('open') vs. strawberries ('protected') there was a significantly higher number of pesticides and proportion of samples with multiple residues for the protected crops. Statistically higher concentrations of pesticides, including cypermethrin, cyprodinil, fenhexamid, boscalid and iprodione were also found in the protected crops compared to the open crops. The evidence here demonstrates that, in general, the protected crops possess a higher number of detectable pesticides compared to analogous crops grown in the open. This may be due to different pesticide-use regimes, but also due to slower rates of pesticide removal in protected systems. The findings of this study raise implications for pesticide management in protected-crop systems. PMID:25465948

  15. Specific antibody for pesticide residue determination produced by antibody-pesticide complex

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new method for specific antibody production was developed using antibody (Ab)-pesticide complex as a unique immunogen. Parathion (PA) was the targeted pesticide, and rabbit polyclonal antibody (Pab) and mouse monoclonal antibody (Mab) were used as carrier proteins. The Ab-PA complexes were genera...

  16. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for detection and identification of albumin phosphylation by organophosphorus pesticides and G- and V-type nerve agents.

    PubMed

    John, Harald; Breyer, Felicitas; Thumfart, Jörg Oliver; Höchstetter, Hans; Thiermann, Horst

    2010-11-01

    Toxic organophosphorus compounds (OPC), e.g., pesticides and nerve agents (NA), are known to phosphylate distinct endogenous proteins in vivo and in vitro. OPC adducts of butyrylcholinesterase and albumin are considered to be valuable biomarkers for retrospective verification of OPC exposure. Therefore, we have detected and identified novel adducts of human serum albumin (HSA) by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Pure albumin and plasma were incubated with numerous pesticides and NA of the V- and G-type in different molar ratios. Samples were prepared either by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by in-gel enzymatic cleavage using endoproteinase Glu-C (Glu-C) or by combining highly albumin-selective affinity extraction with ultrafiltration followed by reduction, carbamidomethylation, and enzymatic cleavage (Glu-C) prior to MALDI-TOF MS analysis. Characteristic mass shifts for phosphylation revealed tyrosine adducts at Y(411) (Y(401)KFQNALLVRY(411)TKKVPQVSTPTLVE(425)), Y(148) and Y(150) (I(142)ARRHPY(148)FY(150)APE(153), single and double labeled), and Y(161) (L(154)LFFAKRY(161)KAAFTE(167)) produced by original NA (tabun, sarin, soman, cyclosarin, VX, Chinese VX, and Russian VX) as well as by chlorpyrifos-oxon, diisopropyl fluorophosphate (DFP), paraoxon-ethyl (POE), and profenofos. MALDI-MS/MS of the single-labeled I(142)-E(153) peptide demonstrated that Y(150) was phosphylated with preference to Y(148). Aged albumin adducts were not detected. The procedure described was reproducible and feasible for detection of adducts at the most reactive Y(411)-residue (S/N ≥ 3) when at least 1% of total albumin was labeled. This was achieved by incubating plasma with molar HSA/OPC ratios ranging from approximately 1:0.03 (all G-type NA, DFP, and POE) to 1:3 (V-type NA, profenofos). Relative signal intensity of the Y(411) adduct correlated well with the spotted relative

  17. Monitoring of pesticide residue in bovine milk from Nadia district, West Bengal.

    PubMed

    Singh, Aruna Kumari; Sar, Tapas Kumar; Mandal, Tapan Kumar

    2013-07-01

    Monitoring of 210 bovine milk samples collected from local markets in the Nadia district of West Bengal during 2011 was performed. Samples were collected in summer and winter seasons. Analysis of pesticides was performed by using a multiresidue method validated in the laboratory. The quantification was performed using GC-ECD. Analysis revealed the presence of lindane in less than 1 % of milk samples. Endosulfan I and II were also detected and were found to exceed MRL recommended by Codex. Overall 1.90 % of the analyzed samples showed trace to measurable amount of pesticide residues. The monitored area provided pesticide residues data of milk, assisting in future scientific assessment on pesticide usage. PMID:23708263

  18. Method for determination of organohalogen pesticide residues in vegetable oil refinery by-products.

    PubMed

    Young, S; Clower, M; Roach, J A

    1984-01-01

    A method using gel permeation and Florisil column chromatographic cleanup techniques is described for determination of residues of nonpolar organohalogen pesticides and pesticide alteration products in vegetable oils and their refinery by-products. Supplemental Florisil separation and alkali cleanup techniques are used to facilitate determinations. Residues are determined with a 63Ni electron capture gas chromatographic detection system used in conjunction with 3 different gas chromatographic columns. Residue identities are confirmed by gas chromatography-mass spectrometry. Recoveries of 7 organohalogen pesticides, ranging from 90 to 103%, were determined by the supplemental Florisil separation technique to augment previously reported recovery data determined for initial GPC and Florisil cleanup steps. Soybean, peanut, and cottonseed deodorizer distillates and crude and refined oil, as well as additional refinery by-products, were analyzed. Nine to 13 organohalogen residues ranging from 0.5 to 6.3 ppm were determined in the 2 soybean deodorizer distillate samples used to develop and test the method. Identities of residues present at greater than or equal to 0.3 ppm were confirmed by gas chromatography-mass spectrometry. An intralaboratory trial of the method provided additional recovery and residue determination data as follows: Recoveries ranging from 102 to 116% were obtained for 4 pesticides added to peanut oil deodorizer distillate. Residues determined in 1 soybean deodorizer distillate sample supported previously obtained data for this sample. PMID:6698936

  19. Food safety in Thailand 2: Pesticide residues found in Chinese kale (Brassica oleracea), a commonly consumed vegetable in Asian countries.

    PubMed

    Wanwimolruk, Sompon; Kanchanamayoon, Onnicha; Phopin, Kamonrat; Prachayasittikul, Virapong

    2015-11-01

    There is increasing public concern over human health risks associated with extensive use of pesticides in agriculture. Regulation of pesticide maximum residue limits (MRLs) in food commodities is established in many developed countries. For Thailand, this regulation exists in law but is not fully enforced. Therefore, pesticide residues in vegetables and fruits have not been well monitored. This study investigated the pesticide residues in Chinese kale, a commonly eaten vegetable among Asians. The Chinese kale samples (N = 117) were purchased from markets in Nakhon Pathom Province, Thailand, and analyzed for the content of 28 pesticides. Analysis was performed by the multiresidual extraction followed by GC-MS/MS. Of pesticides investigated, 12 pesticides were detected in 85% of the Chinese kale samples. Although carbaryl, deltamethrin, diazinon, fenvalerate and malathion were found in some samples, their levels were lower than their MRLs. However, in 34 samples tested, either carbofuran, chlorpyrifos, chlorothalonil, cypermethrin, dimethoate, metalaxyl or profenofos was detected exceeding their MRLs. This represents a 29% rate of pesticide detection above the MRL; a rate much higher than in developed countries. Washing vegetables under running water significantly reduced (p < 0.05) profenofos residues by 55%. The running water method did not significantly decrease cypermethrin residues in the samples but washing with vinegar did. Our research suggests that routine monitoring of pesticide residues is necessary to reduce the public health risks associated with eating contaminated vegetables. Washing vegetables before consumption is advisable as this helps to reduce the level of pesticide residues in our daily intake. PMID:26093223

  20. Kuwait's total diet study: dietary intake of organochlorine, carbamate, benzimidazole and phenylurea pesticide residues.

    PubMed

    Sawaya, W N; al-Awadhi, F A; Saeed, T; al-Omair, A; Ahmad, N; Husain, A; Khalafawi, S; al-Omirah, H; Dashti, B; al-Amiri, H; al-Saqer, J

    1999-01-01

    The State of Kuwait in cooperation with the U.S. Food and Drug Administration (FDA) conducted a Total Diet Study (TDS) to estimate intakes of pesticide residues by the population. The levels of organochlorine (OC) pesticides, carbamates, benzimidazoles, and phenylureas in the TDS core list are reported here. The TDS core list was established through a national food consumption survey. All food items (140 for the Kuwaiti adult) were prepared as eaten and analyzed for the pesticides mentioned above. The FDA's multiresidue methods in Volume I of the Pesticide Analytical Manual were used in gas, liquid, and gel permeation chromatographic analyses. Only vegetable and fruit samples contained pesticide residues (mg/kg), including the carbamates 1-naphthol (1.4) and 3H-carbofuran (0.94) in carrots; the OC pesticide vinclozolin (0.47), 3H-carbofuran (0.66), and fenuron (0.6) in kiwi fruit; the OC pesticide procymidone (0.32) and carbendazim (0.5) in grapes; 3H-carbofuran (5.0) in apricots; the OC pesticides captan (0.013) and thiabendazole (0.63) in pears; captan (0.035) in plums; and carbendazim (0.4) in mandarin oranges. The levels of 3H-carbofuran found in both apricots and kiwi fruit exceeded the maximum residue limits (MRLs) of the Food and Agriculture Organization/World Health Organization (FAO/WHO) of the United Nations. The daily intakes of pesticides by the different population groups are discussed in light of the FAO/WHO acceptable daily intakes. PMID:10589497

  1. Ascorbic acid surface modified TiO2-thin layers as a fully integrated analysis system for visual simultaneous detection of organophosphorus pesticides

    NASA Astrophysics Data System (ADS)

    Li, Shunxing; Liang, Wenjie; Zheng, Fengying; Lin, Xiaofeng; Cai, Jiabai

    2014-11-01

    TiO2 photocatalysis and colorimetric detection are coupled with thin layer chromatography (TLC) for the first time to develop a fully integrated analysis system. Titania@polystyrene hybrid microspheres were surface modified with ascorbic acid, denoted AA-TiO2@PS, and used as the stationary phase for TLC. Because the affinity between AA-TiO2@PS and organophosphorus pesticides (OPs) was different for different species of OPs (including chlopyrifos, malathion, parathion, parathion-methyl, and methamidophos), OPs could be separated simultaneously by the mobile phase in 12.0 min with different Rf values. After surface modification, the UV-vis wavelength response range of AA-TiO2@PS was expanded to 650 nm. Under visible-light irradiation, all of the OPs could be photodegraded to PO43- in 25.0 min. Based on the chromogenic reaction between PO43- and chromogenic agents (ammonium molybdate and ascorbic acid), OPs were quantified from color intensity images using a scanner in conjunction with image processing software. So, AA-TiO2@PS was respectively used as the stationary phase of TLC for efficient separation of OPs, as a photocatalyst for species transformation of phosphorus, and as a colorimetric probe for on-field simultaneous visual detection of OPs in natural water. Linear calibration curves for each OP ranged from 19.3 nmol P L-1 to 2.30 μmol P L-1. This integrated analysis system was simple, inexpensive, easy to operate, and sensitive.TiO2 photocatalysis and colorimetric detection are coupled with thin layer chromatography (TLC) for the first time to develop a fully integrated analysis system. Titania@polystyrene hybrid microspheres were surface modified with ascorbic acid, denoted AA-TiO2@PS, and used as the stationary phase for TLC. Because the affinity between AA-TiO2@PS and organophosphorus pesticides (OPs) was different for different species of OPs (including chlopyrifos, malathion, parathion, parathion-methyl, and methamidophos), OPs could be separated

  2. A review on the fermentation of foods and the residues of pesticides-biotransformation of pesticides and effects on fermentation and food quality.

    PubMed

    Regueiro, Jorge; López-Fernández, Olalla; Rial-Otero, Raquel; Cancho-Grande, Beatriz; Simal-Gándara, Jesús

    2015-01-01

    Residues of pesticides in food are influenced by processing such as fermentation. Reviewing the extensive literature showed that in most cases, this step leads to large reductions in original residue levels in the fermented food, with the formation of new pesticide by-products. The behavior of residues in fermentation can be rationalized in terms of the physical-chemical properties of the pesticide and the nature of the process. In addition, the presence of pesticides decrease the growth rate of fermentative microbiota (yeasts and bacterias), which provokes stuck and sluggish fermentations. These changes have in consequence repercussions on several aspects of food sensory quality (physical-chemical properties, polyphenolic content, and aromatic profile) of fermented food. The main aim of this review is to deal with all these topics to propose challenging needs in science-based quality management of pesticides residues in food. PMID:24915365

  3. A Comprehensive Evaluation of the Efficacy of Leading Oxime Therapies in Guinea Pigs Exposed to Organophosphorus Chemical Warfare Agents or Pesticides

    PubMed Central

    Wilhelm, Christina M.; Snider, Thomas H.; Babin, Michael C.; Jett, David A.; Platoff, Gennady E.; Yeung, David T.

    2014-01-01

    The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection at the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl2, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 hours post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman’s method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes. PMID:25448441

  4. Severity and prognosis of acute organophosphorus pesticide poisoning are indicated by C-reactive protein and copeptin levels and APACHE II score

    PubMed Central

    WU, XINKUAN; XIE, WEI; CHENG, YUELEI; GUAN, QINGLONG

    2016-01-01

    The aim of the present study was to investigate the plasma levels of C-reactive protein (CRP) and copeptin, in addition to the acute physiology and chronic health evaluation II (APACHE II) scores, in patients with acute organophosphorus pesticide poisoning (AOPP). A total of 100 patients with AOPP were included and divided into mild, moderate and severe groups according to AOPP diagnosis and classification standards. Blood samples were collected from all patients on days 1, 3 and 7 following AOPP. The concentrations of CRP and copeptin in the plasma were determined using enzyme-linked immunosorbent assay. All AOPP patients underwent APACHE II scoring and the diagnostic value of these scores was analyzed using receiver operating characteristic curves (ROCs). On days 1, 3 and 7 after AOPP, the levels of CRP and copeptin were increased in correlation with the increase in AOPP severity, and were significantly higher compared with the control groups. Furthermore, elevated CRP and copeptin plasma levels were detected in patients with severe AOPP on day 7, whereas these levels were reduced in patients with mild or moderate AOPP. APACHE II scores, blood lactate level, acetylcholine esterase level, twitch disappearance time, reactivating agent dose and inability to raise the head were the high-risk factors that affected the prognosis of AOPP. Patients with plasma CRP and copeptin levels higher than median values had worse prognoses. The areas under curve for ROCs were 0.89, 0.75 and 0.72 for CRP levels, copeptin levels and APACHE II scores, respectively. In addition, the plasma contents of CRP and copeptin are increased according to the severity of AOPP. Therefore, the results of the present study suggest that CRP and copeptin levels and APACHE II scores may be used for the determination of AOPP severity and the prediction of AOPP prognosis. PMID:26997996

  5. Highly Sensitive and Selective Immuno-capture/Electrochemical Assay of Acetylcholinesterase Activity in Red Blood Cells: A Biomarker of Exposure to Organophosphorus Pesticides and Nerve Agents

    SciTech Connect

    Chen, Aiqiong; Du, Dan; Lin, Yuehe

    2012-02-09

    Acetylcholinesterase (AChE) enzyme activity in red blood cells (RBCs) is a useful biomarker for biomonitoring of exposures to organophosphorus (OP) pesticides and chemical nerve agents. In this paper, we reported a new method for AChE activity assay based on selective immuno-capture of AChE from biological samples followed by enzyme activity assay of captured AChE using a disposable electrochemical sensor. The electrochemical sensor is based on multiwalled carbon nanotubes-gold nanocomposites (MWCNTs-Au) modified screen printed carbon electrode (SPCE). Upon the completion of immunoreaction, the target AChE (including active and inhibited) is captured onto the electrode surface and followed by an electrochemical detection of enzymatic activity in the presence of acetylthiocholine. A linear response is obtained over standard AChE concentration range from 0.1 to 10 nM. To demonstrate the capability of this new biomonitoring method, AChE solutions dosed with different concentration of paraoxon were used to validate the new AChE assay method. AChE inhibition in OP dosed solutions was proportional to its concentration from 0.2 to 50 nM. The new AChE activity assay method for biomonitoring of OP exposure was further validated with in-vitro paraoxon-dosed RBC samples. The established electrochemical sensing platform for AChE activity assay not only avoids the problem of overlapping substrate specificity with esterases by using selective antibody, but also eliminates potential interference from other electroactive species in biological samples. It offers a new approach for sensitive, selective, and rapid AChE activity assay for biomonitoring of exposures to OPs.

  6. Toxicity and median effective doses of oxime therapies against percutaneous organophosphorus pesticide and nerve agent challenges in the Hartley guinea pig.

    PubMed

    Snider, Thomas H; Babin, Michael C; Jett, David A; Platoff, Gennady E; Yeung, David T

    2016-01-01

    Anticholinesterases, such as organophosphorus pesticides and warfare nerve agents, present a significant health threat. Onset of symptoms after exposure can be rapid, requiring quick-acting, efficacious therapy to mitigate the effects. The goal of the current study was to identify the safest antidote with the highest therapeutic index (TI = oxime 24-hr LD50/oxime ED50) from a panel of four oximes deemed most efficacious in a previous study. The oximes tested were pralidoxime chloride (2-PAM Cl), MMB4 DMS, HLö-7 DMS, and obidoxime Cl2. The 24-hr median lethal dose (LD50) for the four by intramuscular (IM) injection and the median effective dose (ED50) were determined. In the ED50 study, male guinea pigs clipped of hair received 2x LD50 topical challenges of undiluted Russian VX (VR), VX, or phorate oxon (PHO) and, at the onset of cholinergic signs, IM therapy of atropine (0.4 mg/kg) and varying levels of oxime. Survival was assessed at 3 hr after onset clinical signs. The 3-hr 90th percentile dose (ED90) for each oxime was compared to the guinea pig pre-hospital human-equivalent dose of 2-PAM Cl, 149 µmol/kg. The TI was calculated for each OP/oxime combination. Against VR, MMB4 DMS had a higher TI than HLö-7 DMS, whereas 2-PAM Cl and obidoxime Cl2 were ineffective. Against VX, MMB4 DMS > HLö-7 DMS > 2-PAM Cl > obidoxime Cl2. Against PHO, all performed better than 2-PAM Cl. MMB4 DMS was the most effective oxime as it was the only oxime with ED90 < 149 µmol/kg against all three topical OPs tested. PMID:27432237

  7. Preparation, characterization of Fe3O4 at TiO2 magnetic nanoparticles and their application for immunoassay of biomarker of exposure to organophosphorus pesticides.

    PubMed

    Zhang, Xiao; Wang, Hongbo; Yang, Chunming; Du, Dan; Lin, Yuehe

    2013-03-15

    Novel Fe(3)O(4) at TiO(2) magnetic nanoparticles were prepared and developed for a new nanoparticle-based immunosensor for electrochemical quantification of organophosphorylated butyrylcholinesterase (BChE) in plasma, a specific biomarker of exposure to organophosphorus (OP) agents. The Fe(3)O(4) at TiO(2) nanoparticles were synthesized by hydrolysis of tetrabutyltitanate on the surface of Fe(3)O(4) magnetic nanospheres, and characterized by attenuated total reflection Fourier-transform infrared spectra, transmission electron microscope and X-ray diffraction. The functional Fe(3)O(4) at TiO(2) nanoparticles were performed as capture antibody to selectively enrich phosphorylated moiety instead of phosphoserine antibody in the traditional sandwich immunoassays. The secondary recognition was performed by quantum dots (QDs)-tagged anti-BChE antibody (QDs-anti-BChE). With the help of a magnet, the resulting sandwich-like complex, Fe(3)O(4) at TiO(2)/OP-BChE/QDs-anti-BChE, was easily isolated from sample solutions and the released cadmium ions were detected on a disposable screen-printed electrode (SPE). The binding affinities were investigated by both surface plasmon resonance (SPR) and square wave voltammetry (SWV). This method not only avoids the drawback of unavailability of commercial OP-specific antibody but also amplifies detection signal by QDs-tags together with easy separation of samples by magnetic forces. The proposed immunosensor yields a linear response over a broad OP-BChE concentrations range from 0.02 to 10 nM, with detection limit of 0.01 nM. Moreover, the disposable nanoparticle-based immunosensor has been validated with human plasma samples. It offers a new method for rapid, sensitive, selective and inexpensive screening/evaluating exposure to OP pesticides and nerve agents. PMID:23122753

  8. Preparation, characterization of Fe3O4 at TiO2 magnetic nanoparticles and their application for immunoassay of biomarker of exposure to organophosphorus pesticides

    SciTech Connect

    Zhang, Xiao; Wang, Hongbo; Yang, Chunming; Du, Dan; Lin, Yuehe

    2013-03-15

    Novel Fe3O4 at TiO2 magnetic nanoparticles were prepared and developed for a new nanoparticle-based immunosensor for electrochemical quantification of organophosphorylated butyrylcholinesterase (BChE) in plasma, a specific biomarker of exposure to organophosphorus (OP) agents. The Fe3O4 at TiO2 nanoparticles were synthesized by hydrolysis of tetrabutyltitanate on the surface of Fe3O4 magnetic nanospheres, and characterized by attenuated total reflection Fourier-transform infrared spectra, transmission electron microscope and X-ray diffraction. The functional Fe3O4 at TiO2 nanoparticles were performed as capture antibody to selectively enrich phosphorylated moiety instead of phosphoserine antibody in the traditional sandwich immunoassays. The secondary recognition was served by quantum dots (QDs)-tagged anti-BChE antibody (QDs-anti-BChE). With the help of a magnet, the resulting sandwich-like complex, Fe3O4 at TiO2/OP-BChE/QDs-anti-BChE, was easily isolated from sample solutions and the released cadmium ions were detected on a disposable screen-printed electrode (SPE). The binding affinities were investigated by both surface plasmon resonance (SPR) and square wave voltammetry (SWV). This method not only avoids the drawback of unavailability of commercial OP-specific antibody but also amplifies detection signal by QDs-tags together with easy separation of samples by magnetic forces. The proposed immunosensor yields a linear response over a broad OP-BChE concentrations range from 0.02 to 10 nM, with detection limit of 0.01 nM. Moreover, the disposable nanoparticle-based immunosensor has been validated with human plasma samples. It offers a new method for rapid, sensitive, selective and inexpensive screening/evaluating exposure to OP pesticides.

  9. Effective adsorption and enhanced removal of organophosphorus pesticides from aqueous solution by Zr-based MOFs of UiO-67.

    PubMed

    Zhu, Xiangyang; Li, Bing; Yang, Jian; Li, Yongsheng; Zhao, Wenru; Shi, Jianlin; Gu, Jinlou

    2015-01-14

    Though many efforts have been devoted to the adsorptive removal of hazardous materials of organophosphorus pesticides (OPs), it is still highly desirable to develop novel adsorbents with high adsorption capacities. In the current work, the removal of two representative OPs, glyphosate (GP) and glufosinate (GF), was investigated by the exceptionally stable Zr-based MOFs of UiO-67. The abundant Zr-OH groups, resulting from the missing-linker induced terminal hydroxyl groups and the inherent bridging ones in Zr-O clusters of UiO-67 particles, served as natural anchorages for efficient GP and GF capture in relation with their high affinity toward phosphoric groups in OPs. The correlation between the most significant parameters such as contact time, OPs concentration, adsorbent dose, pH, as well as ionic strength with the adsorption capacities was optimized, and the effects of these parameters on the removal efficiency of GP and GF from the polluted aqueous solution were investigated. The adsorption of GP on UiO-67 was faster than that of GF, and a pseudo-second-order rate equation effectively described the uptake kinetics. The Langmuir model exhibited a better fit to adsorption isotherm than the Freundlich model. Thanks to the strong affinity and adequate pore size, the adsorption capacities in UiO-67 approached as high as 3.18 mmol (537 mg) g(-1) for GP and 1.98 mmol (360 mg) g(-1) for GF, which were much higher than those of many other reported adsorbents. The excellent adsorption characteristics of the current adsorbents toward OPs were preserved in a wide pH window and high concentration of the background electrolytes. These prefigured the promising potentials of UiO-67 as novel adsorbent for the efficient removal of OPs from aqueous solution. PMID:25514633

  10. Pesticides Residue in Drinking Groundwater Resources of Rural Areas in the Northwest of Iran

    PubMed Central

    Shakerkhatibi, Mohammad; Mosaferi, Mohammad; Asghari Jafarabadi, Mohammad; Lotfi, Ehtesham; Belvasi, Mehdi

    2014-01-01

    Background:The majority of rural population in Iran depends on groundwater resources for drinking purposes. In recent years, pesticide contamination of limited water resources has become a serious challenge worldwide. This study quantified the pesticides residue in rural groundwater resources in the northwest of Iran. Methods: A total of 78 groundwater samples were collected in June and Sep-tember 2011 from all 39 drinking water wells. Liquid-liquid extraction (LLE) followed by Gas Chroma9tography/Mass Spectrometry (GC/MS) was used to determine the selected pesticides. Results: Detection frequencies of profenofos, malathion, diazinon, endosulfan, trifluralin, deltamethrin, methyl parathion, and fenitrothion were determined with the concentrations exceeded 0.1 μg/L in 2.6, 17.9, 15.4, 10.3, 2.6, 2.6, 7.7, and 44.9% of the samples, respectively. Total pesticides residue was also ob-served in 26.9% of the samples with concentrations exceeded 0.5 μg/L. Among them, profenofos, malathion and diazinon were detected as the most frequently observed pesticides with the maximum concentrations of 0.542, 0.456 and 0.614 μg/L, respectively. Conclusion: Higher pesticides residue than European Economic Commission (EEC) guidelines occurred in a number of monitored resources. PMID:25648583

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

    PubMed Central

    Mavrikou, Sophie; Flampouri, Kelly; Moschopoulou, Georgia; Mangana, Olga; Michaelides, Alexandros; Kintzios, Spiridon

    2008-01-01

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

  12. A comprehensive evaluation of the efficacy of leading oxime therapies in guinea pigs exposed to organophosphorus chemical warfare agents or pesticides

    SciTech Connect

    Wilhelm, Christina M.; Snider, Thomas H.; Babin, Michael C.; Jett, David A.

    2014-12-15

    The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection at the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl{sub 2}, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 h post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman's method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes. - Highlights: • First comprehensive evaluation of leading AChE oxime reactivators • All oximes are compared against current U.S. therapy 2-PAM Cl. • Relative therapeutic oxime efficacies against OP CWNA and pesticides • Contribution to more effective antidotes

  13. Measurement of pollution levels of organochlorine and organophosphorus pesticides in water, soil, sediment, and shrimp to identify possible impacts on shrimp production at Jiquilisco Bay.

    PubMed

    Nomen, Rosa; Sempere, Julià; Chávez, Francisco; de López, Nelly Amaya; Rovira, Ma Dolores

    2012-09-01

    This study aims to identify levels of several organochlorine and organophosphorus compounds in shrimp-raising areas of coastal El Salvador, to assess potential impacts on shrimp growth and survival that hamper the sustainability of aquaculture in the region. The paper reports the current levels of γ-HCH, 4,4'-DDT, 4,4'-DDE, 4,4'-DDD, endrin, dieldrin, heptachlor, parathion, methyl parathion, and etoprophos in soils (depth 20 cm), sediments (depth 5 cm), shrimp (Penaeus sp.), and water of three rearing ponds and also in the sediment (depth 5 cm) and water surrounding those ponds in Jiquilisco Bay. Sampling was carried out during the dry (January-March) and rainy (June-August) seasons of 2008. The presence of pesticides in the samples of water, shrimp, and sediment at shrimp ponds was not detected in either season; however, in soil samples (depth 20 cm) taken from these ponds, heptachlor, endrin, dieldrin, 4,4'-DDD, and 4,4'-DDT were identified at concentrations below the method limit of quantification (LOQ), and 4,4'-DDE was found in a concentration falling in the range from 3.85 to 19.61 ng/g. In samples of water taken at the bay water intakes to the rearing ponds, we observed dieldrin concentrations in the range between 0.085 ng/mL and 0.182 ng/mL during the dry season. In the samples of sediments taken in the surrounding areas of shrimp ponds, we found-for both seasons-that in 60 % of the samples, 4,4'-DDE was present in concentrations ranging from 3.75 ng/g to 30.97 ng/g. Additionally, in the rainy season, we observed heptachlor in sediment at concentrations below the method quantification limit. It was concluded that organochlorine compounds from pesticides are still present in Jiquilisco Bay, trapped in deep sediment, even though they have been banned since the 1980s. These were not detected in shrimp tissue, surface water, and shallow sediment in rearing ponds, and hence, we do not believe their presence has any major impact on shrimp production in sampled

  14. Chlorinated pesticide residues in sediments from the Arabian Sea along the central west coast of India

    SciTech Connect

    Sarkar, A.; Gupta, R.S.

    1987-12-01

    The problem of environmental contamination by persistent chlorinated pesticides still evokes major concern due to the presence of their residues in the environment and in human tissues. In developing countries like India organochlorine insecticides, especially DDT are extensively being used in agriculture and vector control programs. Few data are available on their levels of concentration from the seas around India. Persistent pesticides residues can be expected to accumulate in marine sediments. However, very little data on this are available along the Indian coast. An attempt has been made in the present communication to identify and quantify some of the chlorinated pesticides residues in the marine sediments collected from different region along the central west coast of India. This is a part of our ongoing project to monitor and map pollutants within the exclusive economic zone of India.

  15. Photoacoustic Spectroscopy as a Non-destructive Tool for Quantification of Pesticide Residue in Apple Cuticle

    NASA Astrophysics Data System (ADS)

    Liu, Lixian; Wang, Yafei; Gao, Chunming; Huan, Huiting; Zhao, Binxing; Yan, Laijun

    2015-06-01

    Photoacoustic spectroscopy (PAS), the non-destructive method to detect residue of dimethyl-dichloro-vinyl-phosphate (DDVP) pesticide in a cuticle of apple, is described. After constructing the PA experimental setup and identifying three characteristic peaks of DDVP in the near ultraviolet region, the PA spectra of an apple cuticle contaminated with DDVP were collected. The artificial neural network method was then applied to analyze data quantitatively. The results show a correlation coefficient exceeding 0.99 and a detection limit of 0.2 ppm, which is within the national food safety standard for maximum residue limits for pesticides in food (GB 2763-2012). This fact and the non-destructive character of PAS make the approach promising for detection of pesticide residue in fruits.

  16. Matrix-Matching as an Improvement Strategy for the Detection of Pesticide Residues.

    PubMed

    Giacinti, Géraldine; Raynaud, Christine; Capblancq, Sophie; Simon, Valérie

    2016-05-01

    More than 90% of the pesticides residues in apples are located in the peel. We developed a gas chromatography/ion trap tandem mass spectrometry method for investigating all detectable residues in the peel of 3 apple varieties. Sample preparation is based on the use of the Quick Easy Cheap Effective Rugged and Safe method on the whole fruit, the flesh, and the peel. Pesticide residues were quantified with solvent-matched and matrix-matched standards, by spiking apple sample extracts. Matrix effects dependent on the type of extract (fruit, flesh, or peel) and the apple variety were detected. The best data processing methods involved normalizing matrix effect rates by matrix-matched internal/external calibration. Boscalid, captan, chlorpyrifos, fludioxonil, and pyraclostrobin were the most frequently detected pesticides. However, their concentrations in the whole fruit were below European maximum residue levels. Despite negative matrix effects, the residues in peel were detected at concentrations up to 10 times higher than those in whole fruits. Consequently, other pesticide residues present at concentrations below the limit of quantification in the whole fruit were detected in the peel. PMID:27095394

  17. Determination of pesticide residues in IPM and non-IPM samples of mango (Mangifera indica).

    PubMed

    Singh, Shashi B; Mukherjee, Irani; Maisnam, Jaya; Kumar, Praveen; Gopal, Madhuban; Kulshrestha, Gita

    2008-05-01

    Studies were conducted to analyze the residue of commonly used pesticides viz. methyl parathion, chloropyrifos, endosulfan, cypermethrin, fenvalerate, carbendazim, imidacloprid and carbaryl in mango, Dashehari variety, integrated pest management (IPM) and non-IPM samples were collected from the IPM and non-IPM orchards, Lucknow, India. We also present a method for the simultaneous determination of these pesticides in mango samples. Residues of methyl parathion, chloropyriphos, endosulfan, cypermethrin, fenvalerate were extracted from the samples with acetone: cyclohexane: ethyl acetate in the ratio 2:1:1 followed by cleanup using neutral alumina. Analysis was performed by gas chromatography-electron capture detector (GC-ECD) with a megabore column (OV-1). Residues of carbendazim, imidacloprid and carbaryl were extracted with acetone and after cleanup, analysis was performed by high performance liquid chromatography (HPLC) using photo diode array (PDA) detector. Recoveries of all the pesticides ranged between 72.7-110.6%, at 0.1 and 1.0 microg g(-1) level of fortification. The residues detected in non-IPM samples of mango were found to be below the prescribed limits of maximum residue limit (MRL) while IPM samples were free from pesticide residues. PMID:18437617

  18. Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

    PubMed Central

    Letort, Sophie; Balieu, Sébastien; Erb, William; Gouhier, Géraldine

    2016-01-01

    Summary The aim of this review is to provide an update on the current use of cyclodextrins against organophosphorus compound intoxications. Organophosphorus pesticides and nerve agents play a determinant role in the inhibition of cholinesterases. The cyclic structure of cyclodextrins and their toroidal shape are perfectly suitable to design new chemical scavengers able to trap and hydrolyze the organophosphorus compounds before they reach their biological target. PMID:26977180

  19. Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds.

    PubMed

    Letort, Sophie; Balieu, Sébastien; Erb, William; Gouhier, Géraldine; Estour, François

    2016-01-01

    The aim of this review is to provide an update on the current use of cyclodextrins against organophosphorus compound intoxications. Organophosphorus pesticides and nerve agents play a determinant role in the inhibition of cholinesterases. The cyclic structure of cyclodextrins and their toroidal shape are perfectly suitable to design new chemical scavengers able to trap and hydrolyze the organophosphorus compounds before they reach their biological target. PMID:26977180

  20. Evaluation of pesticide residues in human blood samples from Punjab (India)

    PubMed Central

    Bedi, Jasbir Singh; Gill, J. P. S.; Kaur, P.; Sharma, A.; Aulakh, R. S.

    2015-01-01

    Aim: The present study was undertaken to estimate the current status of residues of organochlorine pesticides (OCPs), organophosphates (OPs) and synthetic pyrethroids (SPs) pesticides in human blood. Materials and Methods: Human blood samples were analyzed by gas chromatography and confirmed by gas chromatography-mass spectrometry in selective ion monitoring mode. Results: The gas chromatographic analysis of human blood samples collected from Punjab revealed the presence of p,p’-dichlorodiphenyl dichloroethylene (DDE), p,p’ dichlorodiphenyl dichloroethane (DDD), o,p’ DDE and β-endosulfan at mean levels of 15.26, 2.71, 5.62 and 4.02 ng/ml, respectively. p,p’ DDE residue was observed in 18.0% blood samples, and it contributes 55% of the total pesticide burden in human blood. The difference of total dichlorordiphenyl trichloroethane (DDT) between different age groups of humans was found to be statistically significant (p<0.05). The difference of DDT and endosulfan between dietary habits, gender and spraying of pesticides was found statistically non-significant, however endosulfan residues were observed only in pesticide sprayer’s population. Conclusion: Occurrence of p,p’ DDE, p,p’ DDD, o,p’ DDE in human blood indicated restricted use of DDT. However, presence of endosulfan residues in occupationally exposed population is a matter of public health concern. PMID:27046999

  1. Dietary exposure to pesticide residues in Yaoundé: the Cameroonian total diet study.

    PubMed

    Gimou, M-M; Charrondiere, U R; Leblanc, J-C; Pouillot, R

    2008-04-01

    Dietary exposure to pesticide residues was assessed in Yaoundé, Cameroon, using the total diet study (TDS) method. Sixty-three composite samples, representative of the foods as consumed in Yaoundé, were collected, prepared, and analysed for residues of pesticides including organochlorine, organophosphorous, and pyrethroids. A multi-residue method was used with a limit of detection (LOD) of 0.005 mg kg(-1). Additional analyses were performed for dithiocarbamates (LOD=0.050 mg kg(-1)), glyphosate (LOD=0.005 mg kg(-1)) and chlordecone (LOD=0.0008 mg kg(-1)) on certain composites samples. The overall contamination was low with 37 out of 46 pesticides below the LOD in all samples. The estimated upper bound (for values less than the LOD equal the LOD; and values less than the LOQ equal the LOQ) of the mean dietary exposures ranged from 0.24% (cypermethrin) to 3.03% (pirimiphos-methyl) of the acceptable daily intakes (ADIs) for pesticides for which at least one analysis was greater than the LOD. This study suggests a low dietary exposure to pesticide residues in Yaoundé. PMID:18348045

  2. Effect of household and industrial processing on the levels of pesticide residues and degradation products in melons.

    PubMed

    Bonnechère, A; Hanot, V; Bragard, C; Bedoret, T; van Loco, J

    2012-01-01

    Two varieties of melons (Cucumis melo) were treated with two fungicides (carbendazim and maneb) and four insecticides (acetamiprid, cyromazin, imazalil and thiamethoxam) to quantify the effect of household processing on the pesticide residues. To ensure sufficiently high levels of residues in flesh and peel, the most concentrated formulations were applied observing good agricultural practice. The peeling step decreased the concentration of pesticide residues for maneb, imazalil and acetamiprid by more than 90%. Cyromazin, carbendazim and thiamethoxam were reduced by approximately 50%. The reduction of the pesticides could not be fully explained by the systemic character of the pesticides. However, the agricultural practices (time of application), solubility and mode of action (systemic versus contact pesticide) of the pesticides could be used to explain the difference in processing factors for the studied pesticides. Degradation products (melamine and ethylenethiourea) were also investigated in this study, but were not detected. PMID:22489844

  3. Monitoring and risk assessment of 74 pesticide residues in Pu-erh tea produced in Yunnan, China.

    PubMed

    Chen, Hongping; Wang, Qinghua; Jiang, Ying; Wang, Chuanpi; Yin, Peng; Liu, Xin; Lu, Chengyin

    2015-01-01

    A number of 100 Pu-erh tea samples from the 2013 harvest in Yunnan Province (China) were analysed for 74 pesticides. A total of 11 pesticides were detected. At least one pesticide was detected in 56% of the samples. None of these samples contained the 74 monitored pesticides at concentrations above the Chinese maximum residual levels. Imidacloprid, bifenthrin and acetamiprid were most frequently found, with percentages of 53%, 46% and 31%, respectively. These were also the top three pesticides with maximum concentrations of 140, 246 and 672 μg kg⁻¹, respectively. Residual levels of the monitored pesticides showed no significant correlation with the production time or area of Pu-erh tea. Whereas a high incidence of pesticide residues was detected in Pu-erh tea, the contamination levels observed do not pose any serious health risks. PMID:25308103

  4. Effect of Household Coffee Processing on Pesticide Residues as a Means of Ensuring Consumers' Safety.

    PubMed

    Mekonen, Seblework; Ambelu, Argaw; Spanoghe, Pieter

    2015-09-30

    Coffee is a highly consumed and popular beverage all over the world; however, coffee beans used for daily consumption may contain pesticide residues that may cause adverse health effects to consumers. In this monitoring study, the effect of household coffee processing on pesticide residues in coffee beans was investigated. Twelve pesticides, including metabolites and isomers (endosulfan α, endosulfan β, cypermethrin, permethrin, deltamethrin, chlorpyrifos ethyl, heptachlor epoxide, hexachlorobenzene, p'p-DDE, p'p-DDD, o'p-DDT, and p'p-DDT) were spiked in coffee beans collected from a local market in southwestern Ethiopia. The subsequent household coffee processing conditions (washing, roasting, and brewing) were established as closely as possible to the traditional household coffee processing in Ethiopia. Washing of coffee beans showed 14.63-57.69 percent reduction, while the roasting process reduced up to 99.8 percent. Chlorpyrifos ethyl, permethrin, cypermethrin, endosulfan α and β in roasting and all of the 12 pesticides in the coffee brewing processes were not detected. Kruskal-Wallis analysis indicated that the reduction of pesticide residues by washing is significantly different from roasting and brewing (P < 0.0001). However, there was no significant difference between coffee roasting and brewing (P > 0.05). The processing factor (PF) was less than one (PF < 1), which indicates reduction of pesticides under study during processing of the coffee beans. The cumulative effect of the three processing methods has a paramount importance in evaluating the risks associated with ingestion of pesticide residues, particularly in coffee beans. PMID:26344013

  5. Biological and nonbiological modifications of organophosphorus compounds*

    PubMed Central

    Dauterman, W. C.

    1971-01-01

    The general types of biological reaction that are most prominent in the modification of organophosphorus compounds involve the mixed-function oxidases, hydrolases, or transferases. In certain cases, more than one of these reactions may be involved at the same site on the pesticide molecule. Examples of various organophosphorus pesticides that are altered by oxidation, hydrolysis, alkyl- or aryl-group transfer, reduction, and conjugation are discussed. The increase or decrease in toxicity of a pesticide that can result from biological modification is emphasized. Non-biological transformations of organophosphorus compounds involve the effect ou the compounds of such factors as light, air, temperature, and solvent. These factors are discussed with special emphasis on desulfuration, rearrangement, and oxidation. PMID:4938021

  6. Novel solvent-free microwave-assisted extraction coupled with low-density solvent-based in-tube ultrasound-assisted emulsification microextraction for the fast analysis of organophosphorus pesticides in soils.

    PubMed

    Su, Yi-Song; Yan, Cheing-Tong; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2013-07-01

    A novel and rapid solventless microwave-assisted extraction coupled with low-density solvent-based in-tube ultrasound-assisted emulsification microextraction has been developed for the efficient determination of nine organophosphorus pesticides in soils by GC analysis with microelectron capture detection. A specially designed, homemade glass tube inbuilt with a scaled capillary tube was used as an extraction device to collect and measure the separated extractant phase easily. Parameters affecting the efficiencies of the developed method were thoroughly investigated. From experimental results, the following conditions were selected for the extraction of organophosphorus pesticides from 1.0 g of soil sample to 5 mL of aqueous solution under 226 W of microwave irradiation for 2.5 min followed by ultrasound-assisted emulsification microextraction with 20 μL toluene for 30 s and then centrifugation at 3200 rpm for 3 min. Detections were linear in the range of 0.25-10 ng/g with detection limits between 0.04 and 0.13 ng/g for all target analytes. The applicability of the method to real samples was assessed on agricultural contaminated soils and the recoveries ranged between 91.4 and 101.3%. Compared to other methods, the present method was shown to be highly competitive in terms of sensitivity, cost, eco-friendly nature, and analysis speed. PMID:23681938

  7. Effect of Cooking Process on the Residues of Three Carbamate Pesticides in Rice

    PubMed Central

    Shoeibi, Shahram; Amirahmadi, Maryam; Yazdanpanah, Hassan; Pirali-Hamedani, Morteza; Pakzad, Saied Reza; Kobarfard, Farzad

    2011-01-01

    A gas chromatography mass spectrometry with spike calibration curve method was used to quantify three carbamate pesticides residue in cooked white rice and to estimate the reduction percentage of the cooking process duration. The selected pesticides are three carbamate pesticides including carbaryl and pirimicarb that their MRL is issued by “The Institute of Standards of Iran” and propoxur which is used as a widely consumed pesticide in rice. The analytical method entailed the following steps: 1- Blending 15 g cooked sample with 120 mL acetonitrile for 1 min in solvent proof blender, 2- Adding 6 g NaCl and blending for 1 min, 3- Filtering upper layer through 25 g anhydrous Na2SO4, 4- Cleaning up with PSA and MgSO4, 5- Centrifuging for 7 min, 6- Evaporating about 0.3 mL and reconstituting in toluene till 1 mL, 7- Injecting 2 μL extract into GC/MS and analyzing by single quadruple selected ion monitoring GC/MS-SQ-SIM. The concentration of pesticides and the percentage of pesticides amounts after the cooking were determined by gas chromatography mass-spectrometry (GC/MS) using with interpolation of the relative peak areas for each pesticide to internal standard peak area in the sample on the spiked calibration curve. Calibration curve was linear over the range of 25 to 1000 ng/g, and LOQ was 25 ng/g for all three pesticides. The percent of loss for the three pesticides were 78%, 55% and 35% for carbaryl, propoxur and pirimicarb respectively. Different parameters such as vapor pressure, boiling point, and suspect ability of the compound to hydrolysis, could be responsible for the losing of pesticides during the cooking process. PMID:24363690

  8. Determination of organochlorine pesticide residue in sediment and water from the Densu river basin, Ghana.

    PubMed

    Kuranchie-Mensah, Harriet; Atiemo, Sampson Manukure; Palm, Linda Maud Naa-Dedei; Blankson-Arthur, Sarah; Tutu, Anita Osei; Fosu, Paul

    2012-01-01

    The distribution of organochlorine pesticides in the aquatic ecosystem from the Densu river revealed varying levels of concentration in water and the sediment samples. Three locations were sampled along the river to evaluate the levels of organochlorine pesticide residue in the river. Sediment and surface water samples were extracted by soxhlet and liquid-liquid extraction respectively and analyzed using Gas Chromatograph coupled with electron capture detector. The detectable organochlorine pesticides were gamma-hexachlorocyclohexane (HCH), delta-hexachlorocyclohexane, heptachlor, aldrin and dieldrin. The other pesticides that were investigated are gamma-chlordane, alpha endosulfan, endosulfan sulfate, p,p'-DDT and its metabolite p,p'-DDE, methoxychlor, endrin and its metabolite endrin aldehyde and endrin ketone. The order of increasing frequency of detection of samples was higher in sediment than water. In sediment, the mean concentration ranged from 0.030 μg kg(-1) dry weight (endrin) to 10.98 μg kg(-1) dry weight (aldrin). The highest detected concentration of organochlorine in water was endosulfan sulfate with mean concentration of 0.185 μg L(-1). Analysis of variance indicated significant differences for most organochlorine pesticide residue in the sediment sampled from the various locations. Some of the levels of organochlorine pesticides detected in water were relatively high compared to guideline values set by World Health Organization and Australia and thus could be harmful if the trend is not checked. PMID:22123529

  9. Residue levels and risk assessment of pesticides in nuts of China.

    PubMed

    Liu, Yihua; Shen, Danyu; Li, Shiliang; Ni, Zhanglin; Ding, Ming; Ye, Caifen; Tang, Fubin

    2016-02-01

    The pesticide residue levels of three nuts (chestnut, walnut, pinenut) collected from seven main producing areas of China were investigated. Twenty-nine pesticides, including organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and two fungicides (triadimefon and buprofezin) were analyzed by gas chromatography (GC). Four OPs (acephate, dimethoate, chlorpyrifos and parathion-methyl) were found in 11.4% samples, with the concentrations of 19.0 µg kg(-1) to 74.0 µg kg(-1). Six OCs (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) were found in 18.2% samples, with the concentrations of 2.0 µg kg(-1) to 65.7 µg kg(-1). Among OCs, p,p-DDE and α-HCH were the dominant isomer for DDT and HCH. Five PYs (fenpropathrin, fenvalerate, cypermethrin, bifenthrin and cyhalothrin) were found in 15.9% samples, with the concentrations of 2.5 µg kg(-1) to 433.0 µg kg(-1). Fenpropathrin was the most frequently detected pesticide. In addition, triadimefon and buprofezin were detected only in two samples. For the tested nuts, 25.0% samples with multiple residues (containing more than two pesticides) were noted, even up to 9.1% samples with five pesticide residues. The residue of 15.9% samples was higher than the maximum residue limits (MRLs) of China. The short-term risks for the tested nuts were below 1.2%, and the highest long-term risk was 12.58%. The cumulative risk (cHI) for the tested pesticides were 8.43% (OPs), 0.42% (OCs), 12.82% (PYs) and 0.15% (fungicides), respectively. The total cHI was 21.82%. There was no significant health risk for consumers via nuts consumption. PMID:26408971

  10. Microwave-assisted extraction and high-throughput monolithic-polymer-based micro-solid-phase extraction of organophosphorus, triazole, and organochlorine residues in apple.

    PubMed

    Bagheri, Habib; Es'haghi, Ali; Es-Haghi, Ali; Basiripour, Fatemeh

    2016-02-01

    A high-throughput micro-solid-phase extraction device based on a 96-well plate was constructed and applied to the determination of pesticide residues in various apple samples. Butyl methacrylate and ethylene glycol dimethacrylate were copolymerized as a monolithic polymer and placed in the cylindrically shaped stainless-steel meshes of 96-micro-solid-phase extraction device and used as an extracting unit. Before the micro-solid-phase extraction, microwave-assisted extraction was employed to facilitate the transfer of the pesticide residues from the apple matrix to liquid media. Then, 1 mL of the aquatic samples was transferred into the 96-well plate and the 96-micro-solid-phase extraction device was applied for the extraction of the selected pesticides. Influential parameters, such as sorbent-to-sorbent reproducibility, microwave-assisted extraction time, ionic strength and micro-solid-phase extraction time, were optimized. The limits of quantitation were below 120 μg/kg, which are lower than the maximum residue limits. The developed method was successfully implemented for the extraction and determination of the selected pesticides from 20 different apple samples gathered from local markets. Phosalone was identified and quantified at the concentration level of 147 (±16.4) μg/kg in one of the samples. PMID:26614571

  11. Consumer exposure to pesticide residues in apples from the region of south-eastern Poland.

    PubMed

    Szpyrka, Ewa; Kurdziel, Anna; Słowik-Borowiec, Magdalena; Grzegorzak, Magdalena; Matyaszek, Aneta

    2013-11-01

    The production of apples in Poland is the largest among the countries of the European Union, and therefore, the consumption of these fruits is high in our country. The aim of this study was to determine the presence of pesticide residues in Polish apples and to assess if these residues pose a risk to the health of the consumer. Furthermore, compliance with legal regulations concerning the use of plant protection products in crop cultivation was ascertained. Pesticide residues were found in 192 samples (61.5% of tested samples). In six samples (1.9%), residues exceeded maximum residue limits. Violations concerned the insecticides: indoxacarb, diazinon and fenitrothion. The highest long-term consumer exposure was found in the case of consumption of apples with diazinon residue for both groups, adults and toddlers [4% acceptable daily intake (ADI), adults; 21% ADI, toddlers]. The highest values of short-term exposure were obtained in the case of consumption of apples with indoxacarb [5% acute reference dose (ARfD), adults; 27% ARfD, toddlers] and fenitrothion (4% ARfD, adults; 23% ARfD, toddlers). Although fungicides are the pesticides found most often in apples, the consumption of apples with insecticide residues constitutes the greatest hazard to human health. PMID:23666120

  12. Residual pesticide detection on food with particle-enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Ranjan, Bikas; Huang, LiChuan; Masui, Kyoko; Saito, Yuika; Verma, Prabhat

    2014-08-01

    Modern farming relies highly on pesticides to protect agricultural food items from insects for high yield and better quality. Increasing use of pesticide has raised concern about its harmful effects on human health and hence it has become very important to detect even small amount of pesticide residues. Raman spectroscopy is a suitable nondestructive method for pesticide detection, however, it is not very effective for low concentration of pesticide molecules. Here, we report an approach based on plasmonic enhancement, namely, particle enhanced Raman spectroscopy (PERS), which is rapid, nondestructive and sensitive. In this technique, Raman signals are enhanced via the resonance excitation of localized plasmons in metallic nanoparticles. Gold nanostructures are promising materials that have ability to tune surface plasmon resonance frequency in visible to near-IR, which depends on shape and size of nanostructures. We synthesized gold nanorods (GNRs) with desired shape and size by seed mediated growth method, and successfully detected very tiny amount of pesticide present on food items. We also conformed that the detection of pesticide was not possible by usual Raman spectroscopy.

  13. Pesticide residue transfer in Thai farmer families: using structural equation modeling to determine exposure pathways.

    PubMed

    Liu, Hanhua; Hanchenlaksh, Chalalai; Povey, Andrew C; de Vocht, Frank

    2015-01-01

    Use of pesticides in agriculture may lead to downstream exposure of farmers' families to pesticide residues inadvertently taken home. Identification of the independent contribution of different exposure pathways from the farmer to their children can provide clear targets to reduce exposure of farmers' children. Individual contributions of different pesticide transfer exposure pathways were investigated using structural equation modeling methods, and the benefits of these methods compared to standard multiple regression are described. A total of 72 Thai families, consisting of a farmer, a spouse, and a child, participated in this study. Family members completed a questionnaire and self-collected three spot morning urine samples in the spraying season. Urine samples were analyzed for diethyl phosphate, diethyl thiophosphate, diethyl dithiophosphate, dimethyl phosphate, dimethyl thiophosphate, and dimethyl dithiophosphate. A path model was developed based on an a priori hypothesized framework to examine the individual contributions of different exposure pathways that may directly or indirectly affect transfer of pesticide residues from farmers to their children. Transfer from the farmer to the child occurs indirectly, primarily through transfer to the spouse in the first instance, but also through contamination of the home environment. Clear targets for interventions are directly the reduction of farmers' take-home exposures and indirectly frequent cleaning of the home to avoid buildup of pesticide residues. PMID:25407029

  14. Decay of dinitroaniline herbicides and organophosphorus insecticides during brewing of lager beer.

    PubMed

    Navarro, Simón; Pérez, Gabriel; Navarro, Ginés; Mena, Luis; Vela, Nuria

    2006-07-01

    This article examines the fate of four pesticides that can be present during the brewing of lager beer. For this purpose, malted barley was spiked at 2 mg/kg with pendimethalin and trifluralin (dinitroaniline herbicides) and fenitrothion and malathion (organophosphorus insecticides). Analyses of pesticide residues were carried out by a gas chromatograph with an electron capture detector, and their identity was confirmed by gas chromatography-mass spectrometry. Cleanup was necessary for the malt and spent grain samples. Beginning with mashing and ending with the final product 4 months later, various samples (spent grain, sweet wort, brewer wort, and beer) were taken to determine the concentration of the targeted residual pesticides during the various beer making phases. In all cases, the residual levels recorded in sweet wort sampled after the mashing phase were below the respective maximum residue limits established by Spanish legislation for barley. Significant proportions of pesticide residues (17 to 40%) were retained on the spent grain. Applying the standard first-order kinetics equation (r > 0.91), the half-lives obtained for the four compounds during the storage of the spent grain (3.5 months) varied from 138 days (fenitrothion) to 192 days (malathion and pendimethalin). Herbicide residues practically disappeared (<0.3%) after wort boiling, whereas the percentages of the remaining insecticides, fenitrothion and malathion, ranged from 3.5 to 4.3%, respectively, at this time. No residues of dinitroaniline compounds were detected in young beer, whereas there was a significant reduction in fenitrothion (58%) and malathion (71%) residues during fermentation. Lagering and filtering processes also reduced the content of the organophosphorus insecticides (33 to 37%). Finally, after the storage period (3 months), the content of fenitrothion was reduced by 75%, with malathion residues being below its detection limit. PMID:16865906

  15. A Novel Acetylcholinesterase Biosensor: Core-Shell Magnetic Nanoparticles Incorporating a Conjugated Polymer for the Detection of Organophosphorus Pesticides.

    PubMed

    Dzudzevic Cancar, Hurija; Soylemez, Saniye; Akpinar, Yeliz; Kesik, Melis; Göker, Seza; Gunbas, Gorkem; Volkan, Murvet; Toppare, Levent

    2016-03-01

    To construct a sensing interface, in the present work, a conjugated polymer and core-shell magnetic nanoparticle containing biosensor was constructed for the pesticide analysis. The monomer 4,7-di(furan-2-yl)benzo[c][1,2,5]thiadiazole (FBThF) and core-shell magnetic nanoparticles were designed and synthesized for fabrication of the biosensing device. The magnetic nanoparticles were first treated with silica and then modified using carboxyl groups, which enabled binding of the biomolecules covalently. For the construction of the proposed sensor a two-step procedure was performed. First, the poly(FBThF) was electrochemically generated on the electrode surface. Then, carboxyl group modified magnetic nanoparticles (f-MNPs) and acetylcholinesterase (AChE), the model enzyme, were co-immobilized on the polymer-coated surface. Thereby, a robust and novel surface, conjugated polymer bearing magnetic nanoparticles with pendant carboxyl groups, was constructed, which was characterized using Fourier transform infrared spectrometer, cyclic voltammetry, scanning electron microscopy, and contact angle measurements. This novel architecture was then applied as an immobilization platform to detect pesticides. To the best of our knowledge, a sensor design that combines both conjugated polymer and magnetic nanoparticles was attempted for the first time, and this approach resulted in improved biosensor characteristics. Hence, this approach opens a new perspective in the field of enzyme immobilization and sensing applications. Paraoxon and trichlorfon were selected as the model toxicants. To obtain best biosensor performance, optimization studies were performed. Under optimized conditions, the biosensor in concern revealed a rapid response (5 s), a low detection limit (6.66 × 10(-3) mM), and high sensitivity (45.01 μA mM(-1) cm(-2)). The KM(app) value of poly(FBThF)/f-MNPs/AChE were determined as 0.73 mM. Furthermore, there was no considerable activity loss for 10 d for poly

  16. Optical instrument development for detection of pesticide residue in apple surface

    NASA Astrophysics Data System (ADS)

    Dhakal, Sagar; Li, Yongyu; Peng, Yankun; Chao, Kuanglin; Qin, Jianwei

    2013-05-01

    Apple is the world largest produced and consumed fruit item. At the same time, apple ranks number one among the fruit item contaminated with pesticide. This research focuses on development of laboratory based self-developed software and hardware for detection of commercially available organophosphorous pesticide (chlorpyrifos) in apple surface. A laser light source of 785nm was used to excite the sample, and Raman spectroscopy assembled with CCD camera was used for optical data acquisition. A hardware system was designed and fabricated to clamp and rotate apple sample of varying size maintaining constant working distance between optical probe and sample surface. Graphical Users Interface (GUI) based on LabView platform was developed to control the hardware system. The GUI was used to control the Raman system including CCD temperature, exposure time, track height and track centre, data acquisition, data processing and result prediction. Different concentrations of commercially available 48% chlorpyrifos pesticide solutions were prepared and gently placed in apple surface and dried. Raman spectral data at different points from same apple along the equatorial region were then acquired. The results show that prominent peaks at 341cm-1, 632cm-1 and 680 cm-1 represent the pesticide residue. The laboratory based experiment was able to detect pesticide solution of 20ppm within 3 seconds. A linear relation between Raman intensity and pesticide residue was developed with accuracy of 97.8%. The result of the research is promising and thus is a milestone for developing industrially desired real time, non-invasive pesticide residue detection technology in future.

  17. Monitoring of some organochlorine pesticide residues of butter in Konya, Turkey.

    PubMed

    Nizamlioglu, Ferhan; Aktumsek, Abdurrahman; Kara, Huseyin; Dinc, Iffet

    2005-06-01

    Some organochlorine pesticide residues were investigated in the samples of all local commercial butter brands sold in the supermarket in Konya (Turkey). Some of the samples were found to have the DDT complex (DDT, DDD, DDE and isomers), total HCH complex (alpha-HCH, beta-HCH, gamma-HCH), aldrin, dieldrin and endosulfan (I and II). Nearly 94% of the butter samples were found to be contaminated. Endrin and heptachlorine were detected in three and two samples, respectively, while 87% of samples were contaminated by one or more HCH isomers. 78% of the organochlorine pesticide was DDT and/or its metabolites. These results confirmed that butters sold in Konya presented organochlorine pesticide residues indicating a human exposure. PMID:16334269

  18. Sub-Lethal Effects of Pesticide Residues in Brood Comb on Worker Honey Bee (Apis mellifera) Development and Longevity

    PubMed Central

    Wu, Judy Y.; Anelli, Carol M.; Sheppard, Walter S.

    2011-01-01

    Background Numerous surveys reveal high levels of pesticide residue contamination in honey bee comb. We conducted studies to examine possible direct and indirect effects of pesticide exposure from contaminated brood comb on developing worker bees and adult worker lifespan. Methodology/Principal Findings Worker bees were reared in brood comb containing high levels of known pesticide residues (treatment) or in relatively uncontaminated brood comb (control). Delayed development was observed in bees reared in treatment combs containing high levels of pesticides particularly in the early stages (day 4 and 8) of worker bee development. Adult longevity was reduced by 4 days in bees exposed to pesticide residues in contaminated brood comb during development. Pesticide residue migration from comb containing high pesticide residues caused contamination of control comb after multiple brood cycles and provided insight on how quickly residues move through wax. Higher brood mortality and delayed adult emergence occurred after multiple brood cycles in contaminated control combs. In contrast, survivability increased in bees reared in treatment comb after multiple brood cycles when pesticide residues had been reduced in treatment combs due to residue migration into uncontaminated control combs, supporting comb replacement efforts. Chemical analysis after the experiment confirmed the migration of pesticide residues from treatment combs into previously uncontaminated control comb. Conclusions/Significance This study is the first to demonstrate sub-lethal effects on worker honey bees from pesticide residue exposure from contaminated brood comb. Sub-lethal effects, including delayed larval development and adult emergence or shortened adult longevity, can have indirect effects on the colony such as premature shifts in hive roles and foraging activity. In addition, longer development time for bees may provide a reproductive advantage for parasitic Varroa destructor mites. The impact of

  19. Organochlorine pesticide residues in woodcock, soils and earthworms in Louisiana, 1965

    USGS Publications Warehouse

    McLane, M.A.R.; Stickel, L.F.; Newsom, J.D.

    1971-01-01

    Woodcock (Philohela minor), earthworms, and soil samples were collected from January-March 1965, from fields in southeastern Louisiana approximately 3 years after discontinuance of areal treatments with heptachlor in this region. Heptachlor epoxide residues in woodcock averaged 0.42 ppm (dry weight), conspicuously lower than in 1961 and 1962. Residues of DDE in woodcock averaged 3.62 pprn, higher than in birds taken in the same area in 1961-62. Earthworms and soils contained traces of several organochlorine pesticides.

  20. Distribution and migration of pesticide residues in mosquito control impoundments St. Lucie County, Florida, USA

    NASA Astrophysics Data System (ADS)

    Parkinson, R. W.; Wang, T. C.; White, J. R.; David, J. R.; Hoffman, M. E.

    1993-09-01

    This project was designed to: (1) document the distribution and migration of organochlorine pesticide residues within marsh substrates of 18 St. Lucie County mosquito control impoundments located along the Indian River Lagoon estuary, and (2) evaluate the impact of water management techniques on residue mobility. Our results indicate that detectible concentrations of organochlorine compounds, applied between the late 1940s and early 1950s, are present in 16 of the 18 St. Lucie County mosquito control impoundments. These compounds are primarily restricted to the surficial, organic-rich wetland sediment, which, based upon geotechnical analysis, was exposed to the atmosphere at a time when the impoundments were subjected to pesticide treatment. Contaminated sediments are present below the surficial, organic-rich layer, suggesting that some vertical migration of pesticides has occurred. It is unlikely that leaching associated with the downward percolation of impounded water was responsible for this migration as pesticide residues were never detected within the in situ pore waters. An alternative explanation is that biological processes (e.g., rooting, burrowing) facilitated the downward flux of organochlorine compounds into sediment horizons not subjected to direct treatment. Eighty-eight surface water samples obtained from two impoundments subjected to contrasting water management techniques were analyzed for pesticide content. None of the surficial water samples collected in association with these impoundments contained detectible concentrations of organochlorine compounds. These samples were unfiltered and contained as much as 25 mg/1 of particulate organic matter. This suggests that the currently preferred management technique (RIM), which is designed to maintain water quality, limit mosquito production, and provide for ecological continuity, does not hydraulically mobilize pesticide residues into the Indian River Lagoon estuary.

  1. Sample treatment and determination of pesticide residues in fatty vegetable matrices: a review.

    PubMed

    Gilbert-López, Bienvenida; García-Reyes, Juan F; Molina-Díaz, Antonio

    2009-07-15

    A demanding task in pesticide residue analysis is yet the development of multi-residue methods for the determination of pesticides in vegetables with relatively high fat content (i.e. edible oils and fatty vegetables). The separation of pesticides and other chemical contaminants from high-fat food samples prior to subsequent steps in the analytical process is yet a challenging issue to which much effort in method development has being applied. This review addresses the main sample treatment methodologies for pesticide residue analysis in fatty vegetable matrices. Even with the advent of advanced hyphenated techniques based on mass spectrometry these complex fatty matrices usually require extensive sample extraction and purification. Current methods involve the use of one or the combination of some of the following techniques for both the sample extraction and clean-up steps: liquid-liquid partitioning, solid-phase extraction (SPE), gel-permeation chromatography (GPC), matrix solid-phase dispersion (MSPD), etc. An overview of methods developed for these contaminants in fatty vegetables matrices is presented. Sample extraction and purification techniques are discussed and their most recent applications are highlighted. This review emphasizes that sample preparation is a critical step, but also the determination method is, and cannot be treated separately from sample treatment. In recent years, the appearance and use of new, more polar pesticides has fostered the development of liquid chromatography/mass spectrometry (LC-MS) besides gas chromatography. The main features of LC-MS for the analysis of multi-class pesticides in fatty vegetable samples will be also underlined, with an emphasis on the multi-class, multi-residue strategy and the difficulties associated. PMID:19559852

  2. MACRO AND MICRO APPROACHES TO THE DETERMINATION OF PESTICIDE RESIDUES IN HUMAN AND ANIMAL TISSUES

    EPA Science Inventory

    Analytical approaches to the determination of pesticides and metabolites in human and animal tissues will take many forms. Several factors must be considered in choosing an analytical scheme if the results are to be meaningful. Whenever possible the residue chemist will use stand...

  3. QuEChERS sample preparation approach for mass spectrometric analysis of pesticide residues in foods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes an easy, rapid, and low-cost sample preparation approach for the determination of pesticide residues in foods using gas and/or liquid chromatographic (GC and/or LC) analytical separation and mass spectrometric (MS) detection. The approach is known as QuEChERS, which stands fo...

  4. Pesticide and PCB residues in the Neuse River waterdog, Necturus lewisi

    USGS Publications Warehouse

    Hall, R.J.; Prouty, R.M.; Ashton, R.E.

    1985-01-01

    Residues of 6 organochlorine contaminants were found in N. lewisi from 6 sites in the Tar and Neuse river systems. Concentrations of pesticides were low and apparently related to geographic patterns of use. Levels of PCB were higher and did not seem to vary geographically.

  5. Determination of Pesticide Residues in Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate: Collaborative Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A collaborative study was conducted to determine multiple pesticide residues in fruits and vegetables using a quick, simple, inexpensive, and effective sample preparation method followed by concurrent analysis with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass sp...

  6. Comparison of Wipe Materials and Wetting Agents for Pesticide Residue Collection from Hard Surfaces

    EPA Science Inventory

    Different wipe materials and wetting agents have been used to collect pesticide residues from surfaces, but little is known about their comparability. To inform the selection of a wipe for the National Children's Study, the analytical feasibility, collection efficiency, and preci...

  7. Effect of home processing on the distribution and reduction of pesticide residues in apples.

    PubMed

    Kong, Z; Shan, W; Dong, F; Liu, X; Xu, J; Li, M; Zheng, Y

    2012-08-01

    The effect of home processing (washing, peeling, coring and juicing) on residue levels of chlorpyrifos, β-cypermethrin, tebuconazole, acetamiprid and carbendazim in apple segments was investigated. The pesticide residues were determined by UPLC-MS/MS and GC with a flame photometric (FPD) and electron capture detection (ECD). The results indicated that the pesticide residue levels in the apple peel and core were higher compared with in the apple flesh. After peeled and cored apple was processed into apple juice and pomace, chlorpyrifos, β-cypermethrin and tebuconazole were concentrated in the apple pomace. However, residues of acetamiprid and carbendazim were exceptions. The apple pomace was free of acetamiprid, which was mainly present in the apple juice. After washing the mean loss of chlorpyrifos, β-cypermethrin, tebuconazole, acetamiprid and carbendazim from apples under recommended dosage and twofold higher dosage were 17-21%, 6.7-7.1%, 13-32%, 42-67% and 47-50%, respectively. The pesticide residues were significantly reduced in the edible part of the apple except for β-cypermethrin during peeling and coring process. The removal effect of apple juicing was found to be the most pronounced on β-cypermethrin residue, which was reduced in the range of 81-84%, and the reductions of chlorpyrifos, tebuconazole, acetamiprid and carbendazim upon apple juicing were in the range of 15-36%. PMID:22738391

  8. Solar photocatalytic activity of TiO2 modified with WO3 on the degradation of an organophosphorus pesticide.

    PubMed

    Ramos-Delgado, N A; Gracia-Pinilla, M A; Maya-Treviño, L; Hinojosa-Reyes, L; Guzman-Mar, J L; Hernández-Ramírez, A

    2013-12-15

    In this study, the solar photocatalytic activity (SPA) of WO3/TiO2 photocatalysts synthesized by the sol-gel method with two different percentages of WO3 (2 and 5%wt) was evaluated using malathion as a model contaminant. For comparative purpose bare TiO2 was also prepared by sol-gel process. The powders were characterized by X-ray diffraction (XRD), Raman spectroscopy, diffuse reflectance UV-vis spectroscopy (DRUV-vis), specific surface area by the BET method (SSABET), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy with a high annular angle dark field detector (STEM-HAADF). The XRD, Raman, HRTEM and STEM-HAADF analyses indicated that WO3 was present as a monoclinic crystalline phase with nanometric cluster sizes (1.1 ± 0.1 nm for 2% WO3/TiO2 and 1.35 ± 0.3 nm for 5% WO3/TiO2) and uniformly dispersed on the surface of TiO2. The particle size of the materials was 19.4 ± 3.3 nm and 25.6 ± 3 nm for 2% and 5% WO3/TiO2, respectively. The SPA was evaluated on the degradation of commercial malathion pesticide using natural solar light. The 2% WO3/TiO2 photocatalyst exhibited the best photocatalytic activity achieving 76% of total organic carbon (TOC) abatement after 300 min compared to the 5% WO3/TiO2 and bare TiO2 photocatalysts, which achieved 28 and 47% mineralization, respectively. Finally, experiments were performed to assess 2% WO3/TiO2 catalyst activity on repeated uses; after several successive cycles its photocatalytic activity was retained showing long-term stability. PMID:23993423

  9. Magnetic Electrochemical Sensing Platform for Biomonitoring of Exposure to Organophosphorus Pesticides and Nerve Agents Based on Simultaneous Measurement of Total Enzyme Amount and Enzyme Activity

    SciTech Connect

    Du, Dan; Wang, Jun; Wang, Limin; Lu, Donglai; Smith, Jordan N.; Timchalk, Charles; Lin, Yuehe

    2011-05-15

    We report a new approach for electrochemical quantification of enzymatic inhibition and phosphorylation for biomonitoring of exposure to organophosphorus (OP) pesticides and nerve agents based on a magnetic beads (MBs) immunosensing platform. The principle of this approach is based on the combination of MBs immuno-capture based enzyme activity assay and competitive immunoassay of total amount of enzyme for simultaneous detection of enzyme inhibition and phosphorylation in biological fluids. Butyrylcholinesterase (BChE) was chosen as a model enzyme. In competitive immunoassay, the target total BChE in a sample (mixture of OP-inhibited BChE and active BChE) competes with the BChE modified on the MBs to bind to the limited anti-BChE antibody labeled with quantum dots (QDs-anti-BChE), and followed by electrochemical stripping analysis of the bound QDs conjugate on the MBs. This assay shows a linear response over the total BChE concentration range of 0.1~20 nM. Simultaneously, real time BChE activity was measured on an electrochemical carbon nanotube-based sensor coupled with microflow injection system after immuno-capture by MBs-anti-BChE conjugate. Therefore, the formed phosphorylated adduct (OP-BChE) can be estimated by the difference values of the total amount BChE (including active and OP-inhibited) and active BChE from established calibration curves. This approach not only eliminates the difficulty in screening of low-dose OP exposure (less than 20% inhibition of BChE) because of individual variation of BChE values, but also avoids the drawback of the scarce availability of OP-BChE antibody. It is sensitive enough to detect 0.5 nM OP-BChE, which is less than 2% BChE inhibition. This method offers a new method for rapid, accurate, selective and inexpensive quantification of phosphorylated adducts and enzyme inhibition for biomonitoring of OP and nerve agent exposures.

  10. Polydimethylsiloxane/metal-organic frameworks coated stir bar sorptive extraction coupled to gas chromatography-flame photometric detection for the determination of organophosphorus pesticides in environmental water samples.

    PubMed

    Xiao, Zuowei; He, Man; Chen, Beibei; Hu, Bin

    2016-08-15

    In this work, the metal-organic frameworks (MOFs), MIL-101-Cr-NH2 was synthesized via a direct hydrothermal method, and a polydimethylsiloxane (PDMS)/MIL-101-Cr-NH2 coated stir bar was prepared by sol-gel technique. Good reproducibility was obtained for the preparation of PDMS/MIL-101-Cr-NH2 coated stir bar with the relative standard deviations (RSDs) ranging from 3.7 to 5.2% (n=7) in one batch, and from 5.4 to 9.2% (n=7) among different batches. With the high surface area and rich benzene ring structure of MIL-101-Cr-NH2, the prepared PDMS/MIL-101-Cr-NH2 coated stir bar presented higher extraction efficiency for target organophosphorus pesticides (OPPs, including phorate, diazinon, malathion, fenthion, quinalphos and ethion) over PDMS coated stir bar. Based on it, a new method of PDMS/MIL-101-Cr-NH2 coated stir bar sorptive extraction (SBSE) coupled to gas chromatography-flame photometric detection (GC-FPD) was proposed for the determination of six OPPs in environmental water samples. The operation parameters affecting the extraction efficiency of SBSE, including extraction time, stirring rate, desorption time and ionic strength, were investigated. Under the optimal conditions, the limits of detection (S/N=3) were found to be in the range of 0.043-0.085μgL(-1) for the six target OPPs, and the linear range was 0.5-100μgL(-1) for malathion and 0.2-100μgL(-1) for other five OPPs. The RSDs of the proposed method evaluated at 1µgL(-1) for each OPP were in the range of 5.9-8.7% (intra-day, n=7) and 6.1-10.7% (inter-day, n=5), respectively. The enrichment factors were varied from 110 to 151-fold (theoretical enrichment factor was 200-fold). The proposed method was applied to the analysis of OPPs in East Lake and pond water samples with recoveries in the range of 89.3-115% and 80.0-113% for the spiked East Lake and pond water samples, respectively. PMID:27260444

  11. Multi-residue detection of pesticides using a sensitive immunochip assay based on nanogold enhancement.

    PubMed

    Lan, Meijing; Guo, Yirong; Zhao, Ying; Liu, Yihua; Gui, Wenjun; Zhu, Guonian

    2016-09-28

    This paper describes the development of a new multiplex immunoassay for simultaneous detection of seven pesticides (triazophos, methyl-parathion, fenpropathrin, carbofuran, thiacloprid, chlorothalonil, and carbendazim). Sixteen pairs of pesticide antibodies and antigens were screened for reactivity and cross-reaction. A microarray chip consisting of seven antigens immobilized on a nitrocellulose membrane was then constructed. Nanogold was employed for labeling and signal amplification to obtain a sensitive colorimetric immunoassay. The direct and indirect detection formats were further compared using primary antibody-gold and secondary antibody-gold conjugates as tracers. An integrated 7-plex immunochip assay based on the indirect model was established and optimized. The detection limits for the pesticides were 0.02-6.45 ng mL(-1), which meets detection requirements for pesticide residues. Naked-eye assessment showed the visual detection limits of the assay ranged from 1 to 100 ng mL(-1). Spiked recovery results demonstrated that the immunochip assay had potential for multi-analysis of pesticide residues in vegetables and fruits. The proposed microarray methodology is a flexible and versatile tool, which can be applied to other competitive multiplex immunoassays for small molecular compounds. PMID:27619097

  12. Pesticide residues in drinking water and associated risk to consumers in Ethiopia.

    PubMed

    Mekonen, Seblework; Argaw, Roba; Simanesew, Aklilu; Houbraken, Michael; Senaeve, David; Ambelu, Argaw; Spanoghe, Pieter

    2016-11-01

    Access to safe and reliable drinking water is vital for a healthy population. However, surface water may be contaminated with pesticides because of the nearby agricultural areas as well as from household application. Water samples were collected from water sources in Jimma zone and Addis Ababa, Ethiopia. The extraction and clean up of the samples were undertaken using liquid-solid and liquid-liquid methods. Human exposure was assessed by calculating the estimated daily intake (EDI) of pesticides in water and compared with the acceptable daily intake (ADI) and the acute reference dose (ARfD). The mean concentrations of 2,4-D, malathion, diazinon and fenpropimorph were 1.59-13.90 μg/l and 0.11-138 µg/l in Jimma and Addis Ababa water sources, respectively. The residue level of some of the pesticides were above the European drinking water guide line values, which is an indication of an illegal use of pesticides in the study areas. Concerning human health risk estimation, there was no acute risk (EDI < ARfD). However, chronic risks to human health were observed from exposure to diazinon and fenpropimorph (EDI > ADI) for Jimma and Addis Ababa populations, respectively. A comprehensive monitoring is required to reduce the level of pesticide residues in the water and to minimize particularly the long term human health risks. PMID:27501312

  13. Residues levels of organochlorine pesticide in cow's milk from industrial farms in Hidalgo, Mexico.

    PubMed

    Gutierrez, Rey; Ortiz, Rutilio; Vega, Salvador; Schettino, Beatriz; Ramirez, Maria L; Perez, Jose J

    2013-01-01

    A survey was carried out from 2008 to 2010 to determine the concentrations of 16 organochlorine pesticide residues (OPRs) from Tizayuca, Hidalgo, Mexico. Organochlorine residue determinations were made from milk fat, using chromatographic cleanup and analysis by gas chromatography with an electron capture detector. The OPR concentrations found were from below the detection limit (DL) to 0.91 ng g(-1) in 2008, DL to 0.38 ng g(-1) in 2009 and DL to 0.59 ng g(-1) in 2010. In general concentrations of organochlorine pesticides were higher in the wet season (3.37 ng g(-1) and 4.79 ng g(-1)) than the dry season (1.92 ng g(-1) and 2.71 ng g(-1)) for 2009 and 2010, due to control of pests in the pasture and sheds. According to Codex Alimentarius regulations, individual pesticides did not exceed the permissible limits, which for example were 10 μg kg(-)1 for alpha hexachlorocyclohexane (HCH) and endosulfan I, 20 μg kg(-1) for p,p'-DDT, and 6 μg kg(-1) for dieldrin, endrin and heptachlor. A reduction of organochlorine pesticide concentrations in cow's milk was noted, indicating that the Mexican government has achieved reduction or elimination of some organochlorine pesticides in response to global agreements on persistent organic pollutants. PMID:23998305

  14. Assessment of organochlorine pesticide residues in soils and drinking water sources from cocoa farms in Ghana.

    PubMed

    Fosu-Mensah, Benedicta Y; Okoffo, Elvis D; Darko, Godfred; Gordon, Christopher

    2016-01-01

    Residues of organochlorine pesticides were determined in soils and drinking water sources in cocoa growing areas in Ghana. Soil samples analysed showed the presence of four organochlorine pesticide residues namely lindane (0.005-0.05 mg/kg), beta-HCH (<0.01-0.05 mg/kg), dieldrin (0.005-0.02 mg/kg), and p,p'-DDT (0.005-0.04 mg/kg), with dieldrin occurring most frequently. Similarly, organochlorine pesticide residues detected in the water samples were lindane (0.01-0.03 µg/l), alpha-endosulfan (0.01-0.03 µg/l), endosulfan-sulphate (0.01-0.04 µg/l), dieldrin (0.01-0.03 µg/l) and p,p'-DDT (0.01-0.04 µg/l), with heptachlor occurring most frequently. The concentrations of the detected organochlorine residues in the soil samples were below their respective US maximum residues limits (MRLs) for agricultural soils, except for lindane recorded at Kwakuanya (S4) and beta-HCH recorded at Krakrom (S3) and Kwakuanya (S4). Similarly, the organochlorine pesticide residues recorded in the water samples were below and within their respective WHO MRLs for drinking water except for alpha-endosulfan at Diabaa (S2) and Kwakuanya (S4) at distance 0-15 m and Kwakuanya (S4) at distance 16-30 m, endosulfan-sulfate at Nkrankwanta (S1) and Diabaa (S2) at distance 0-15 m and heptachlor at Krakrom (S3) at distance 16-30 m which were above their WHO MRLs. The presence of the banned organochlorine pesticide residues in soil and water samples from the study area indicates that these chemicals are still being used, illegally, on some cocoa farms. Routine monitoring of pesticide residues in the study area is necessary for the prevention, control and reduction of environmental pollution to minimize health risks. PMID:27386318

  15. Earthworm tolerance to residual agricultural pesticide contamination: field and experimental assessment of detoxification capabilities.

    PubMed

    Givaudan, Nicolas; Binet, Françoise; Le Bot, Barbara; Wiegand, Claudia

    2014-09-01

    This study investigates if acclimatization to residual pesticide contamination in agricultural soils is reflected in detoxification, antioxidant enzyme activities and energy budget of earthworms. Five fields within a joint agricultural area exhibited different chemical and farming histories from conventional cultivation to organic pasture. Soil multiresidual pesticide analysis revealed up to 9 molecules including atrazine up to 2.4 ng g(-1) dry soil. Exposure history of endogeic Aporrectodea caliginosa and Allolobophora chlorotica modified their responses to pesticides. In the field, activities of soluble glutathione-S-transferases (sGST) and catalase increased with soil pesticide contamination in A. caliginosa. Pesticide stress was reflected in depletion of energy reserves in A. chlorotica. Acute exposure of pre-adapted and naïve A. caliginosa to pesticides (fungicide Opus(®), 0.1 μg active ingredient epoxiconazole g(-1) dry soil, RoundUp Flash(®), 2.5 μg active ingredient glyphosate g(-1) dry soil, and their mixture), revealed that environmental pre-exposure accelerated activation of the detoxification enzyme sGST towards epoxiconazole. PMID:24874794

  16. Rapid detection of chlorpyrifos pesticide residue concentration in agro-product using Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Dhakal, Sagar; Peng, Yankun; Li, Yongyu; Chao, Kuanglin; Qin, Jianwei; Zhang, Leilei; Xu, Tianfeng

    2014-05-01

    Different chemicals are sprayed in fruits and vegetables before and after harvest for better yield and longer shelf-life of crops. Cases of pesticide poisoning to human health are regularly reported due to excessive application of such chemicals for greater economic benefit. Different analytical technologies exist to detect trace amount of pesticides in fruits and vegetables, but are expensive, sample destructive, and require longer processing time. This study explores the application of Raman spectroscopy for rapid and non-destructive detection of pesticide residue in agricultural products. Raman spectroscopy with laser module of 785 nm was used to collect Raman spectral information from the surface of Gala apples contaminated with different concentrations of commercially available organophosphorous (48% chlorpyrifos) pesticide. Apples within 15 days of harvest from same orchard were used in this study. The Raman spectral signal was processed by Savitzky-Golay (SG) filter for noise removal, Multiplicative Scatter Correction (MSC) for drift removal and finally polynomial fitting was used to eliminate the fluorescence background. The Raman spectral peak at 677 cm-1 was recognized as Raman fingerprint of chlorpyrifos. Presence of Raman peak at 677 cm-1 after fluorescence background removal was used to develop classification model (presence and absence of pesticide). The peak intensity was correlated with actual pesticide concentration obtained using Gas Chromatography and MLR prediction model was developed with correlation coefficient of calibration and validation of 0.86 and 0.81 respectively. Result shows that Raman spectroscopy is a promising tool for rapid, real-time and non-destructive detection of pesticide residue in agro-products.

  17. Dietary exposure to pesticide residues from foods of plant origin and drinks in Lebanon.

    PubMed

    Nasreddine, Lara; Rehaime, Maria; Kassaify, Zeina; Rechmany, Roula; Jaber, Farouk

    2016-08-01

    This study assesses the dietary exposure of Lebanese adults to 47 pesticide residues from both foods of plant origin and drinks. The study was conducted using the Total Diet Study protocol in two different areas of Lebanon: Greater Beirut (urban) and Keserwan (semi-rural). A total of 1860 individual foods were collected, prepared, and cooked prior to analysis. Composite samples of similar foods were analyzed, following the QuEChERS Multiresidue method. Eighteen residues were detected/quantified on at least one composite sample, with 66.7 % of the results being quantifiable and 33.3 % detectable. Quantifiable levels ranged between 10.3 and 208 μg/kg. For the composite samples where residues were detected, 55 % had one residue, while 45 % had 2-4 residues. The most frequently detected/quantified pesticide residues included Chlorpyrifos, Procymidone, Primiphos methyl, Dimethoate, and Dieldrin. The dietary exposure assessment was conducted using the deterministic approach with two scenarios: (1) the lower bound (LB) approach and (2) the upper bound (UB) approach. Using the LB approach, mean estimated daily exposures were far below the acceptable daily intakes (ADIs) for all investigated residues. Using the UB approach, which tends to overestimate exposure, mean estimated daily exposures were below the ADIs for all residues except for Dieldrin (semi-rural: 128.7 % ADI; urban: 100.7 % ADI). Estimates of mean exposure to Diazinon reached 50.3 % of ADI in the urban diet and 61.9 % in the semi-rural diet. Findings of this study identify specific pesticide residues as monitoring priorities for which more comprehensive and sensitive analyses are needed in order to refine exposure assessment. PMID:27461424

  18. Pesticide Residues in Bovine Milk in Punjab, India: Spatial Variation and Risk Assessment to Human Health.

    PubMed

    Bedi, J S; Gill, J P S; Aulakh, R S; Kaur, Prabhjit

    2015-08-01

    In the present study, gas chromatographic analysis of pesticide residues in bovine milk (n = 312) from Punjab, India, showed chlorpyrifos, DDT, and γ-HCH as the predominant contaminants. In addition, the presence of β-endosulfan, endosulfan suphate, cypermethrin, cyhalothrin, fenvalerate, deltamethrin, malathion, profenofos, and ethion was reported in milk samples. In this study, it was observed that 12 milk samples exceeded the maximum residue limits (MRLs) for γ-HCH (lindane), 18 for DDT and chlorpyrifos, and 1 sample each for endosulfan, cypermethrin, and profenophos. In India, DDT is still permitted for a malaria control program, which may be the plausible reason for its occurrence in milk samples. The spatial variation for presence of pesticide residues in milk indicated greater levels in cotton-growing areas of Punjab. At current levels of pesticide residues in bovine milk, the human health risk assessment in terms of noncancer and cancer hazard was calculated based on both lower-bound [LB (mean residue levels)] and upper-bound [UP (95th percentile level)] limits. It was noticed that cancer and noncancer risk were within United States Environmental Protection Agency prescribed limits for both adults and children at the LB, but children were being exposed to greater risk for DDT and HCH at the 95th-percentile UB level. PMID:26008642

  19. Pesticide residues in groundwater in The Netherlands: state of observations and future directions of research.

    PubMed

    Loch, J P; Verdam, B

    1989-01-01

    In the first stage of a programme of sampling and analysis for pesticide residues in groundwater in The Netherlands, the upper groundwater below four vulnerable soils was analysed for nearly 2,5 years in eight sampling rounds. Of 18 compounds analysed, including some metabolites, 1,3-dichloropropene, aldicarb, ethoprophos dinoseb, metamitron, atrazine, desethyl- and desisopropylatrazine, metolachlor and ethylenethioureum were repeatedly detected in the groundwater in concentrations above 0.1 micrograms.dm-3, the limit for pesticides in drinking water set by the EC. These observations were made below fields with potatoe-, maize- and bulb flower culture, all on low-humic to moderately humic sandy soils. No residues were found below a cracked light clay on a sandy subsoil. On the locations sampled evidence was found for complete in situ removal in the upper groundwater of 1,3-dichloropropene, high persistence of aldicarb residues and partial in situ degradation of dinoseb. PMID:2756375

  20. A perspective of pesticide residue variability and acute dietary risk assessment.

    PubMed

    Walsh, M

    2000-07-01

    The question of the variability of pesticide residues and acute risk assessment has arisen in the context of the work of the European Commission's Scientific Committee for Plants (SCP). A brief outline is presented of European Community legislation on pesticide residues and the authorization of plant protection products. It is stated that although chronic risk assessment is systematically carried out in connection with the fixing of Community MRLs, the same has not applied for acute risk assessment. The reasons for this situation have been the absence of an agreed methodology, acute reference dose (RfD) and adequate dietary and residue data. It is stated that in the opinion of the Scientific Committee for Plants an acute risk assessment should be considered on a routine basis and that steps should be taken to ensure the availability of the necessary data. Possible implications for risk communication and the authorization of plant protection products in the EC are also discussed. PMID:10983589

  1. A residue-free green synergistic antifungal nanotechnology for pesticide thiram by ZnO nanoparticles

    NASA Astrophysics Data System (ADS)

    Xue, Jingzhe; Luo, Zhihui; Li, Ping; Ding, Yaping; Cui, Yi; Wu, Qingsheng

    2014-07-01

    Here we reported a residue-free green nanotechnology which synergistically enhance the pesticides efficiency and successively eliminate its residue. We built up a composite antifungal system by a simple pre-treating and assembling procedure for investigating synergy. Investigations showed 0.25 g/L ZnO nanoparticles (NPs) with 0.01 g/L thiram could inhibit the fungal growth in a synergistic mode. More importantly, the 0.25 g/L ZnO NPs completely degraded 0.01 g/L thiram under simulated sunlight irradiation within 6 hours. It was demonstrated that the formation of ZnO-thiram antifungal system, electrostatic adsorption of ZnO NPs to fungi cells and the cellular internalization of ZnO-thiram composites played important roles in synergy. Oxidative stress test indicated ZnO-induced oxidative damage was enhanced by thiram that finally result in synergistic antifungal effect. By reducing the pesticides usage, this nanotechnology could control the plant disease economically, more significantly, the following photocatalytic degradation of pesticide greatly benefit the human social by avoiding negative influence of pesticide residue on public health and environment.

  2. A residue-free green synergistic antifungal nanotechnology for pesticide thiram by ZnO nanoparticles

    PubMed Central

    Xue, Jingzhe; Luo, Zhihui; Li, Ping; Ding, Yaping; Cui, Yi; Wu, Qingsheng

    2014-01-01

    Here we reported a residue-free green nanotechnology which synergistically enhance the pesticides efficiency and successively eliminate its residue. We built up a composite antifungal system by a simple pre-treating and assembling procedure for investigating synergy. Investigations showed 0.25 g/L ZnO nanoparticles (NPs) with 0.01 g/L thiram could inhibit the fungal growth in a synergistic mode. More importantly, the 0.25 g/L ZnO NPs completely degraded 0.01 g/L thiram under simulated sunlight irradiation within 6 hours. It was demonstrated that the formation of ZnO-thiram antifungal system, electrostatic adsorption of ZnO NPs to fungi cells and the cellular internalization of ZnO-thiram composites played important roles in synergy. Oxidative stress test indicated ZnO-induced oxidative damage was enhanced by thiram that finally result in synergistic antifungal effect. By reducing the pesticides usage, this nanotechnology could control the plant disease economically, more significantly, the following photocatalytic degradation of pesticide greatly benefit the human social by avoiding negative influence of pesticide residue on public health and environment. PMID:25023938

  3. Occurrence and estimation of pesticide residues in edible minor crops in southeastern Poland in 2013-2014.

    PubMed

    Podbielska, Magdalena; Szpyrka, Ewa; Matyaszek, Aneta; Słowik-Borowiec, Magdalena; Rupar, Julian; Kurdziel, Anna

    2016-07-01

    This paper presents the results of official control of pesticide residues in minor crops collected in southeastern Poland in 2013-2014. Compliance of used pesticides with applicable law was also verified, and determined residues were compared to maximum residue levels (MRLs) provided for in Regulation (EC) No. 395/2005. A total of 583 samples of 25 different types of fresh fruit and vegetables were analyzed for pesticide residues. Pesticide residues were detected in 158 samples (27.1 % of the analyzed samples). According to the European Commission Health & Consumer Protection Directorate-General (SANCO) guidelines document, MRL violations were understood as cases where a residue level exceeded the MRL after the uncertainty of the method (50 %) was considered. MRL violations were found in four samples. The usage of unauthorized pesticides was detected in 5.8 % of analyzed samples. Substances banned in Poland were found in two samples. Fungicides were the most frequently detected group of pesticides. Pesticide residues were most commonly found in fruit samples (19.4 % of all analyzed samples), mainly in gooseberry, redcurrant, and huckleberry. The majority of samples were compliant with MRLs, which means that they were suitable for trade. PMID:27251221

  4. Residues of organochlorine pesticides and polychlorinated biphenyls and autopsy data for bald eagles, 1973-74

    USGS Publications Warehouse

    Prouty, R.M.; Reichel, W.L.; Locke, L.N.; Belisle, A.A.; Cromartie, E.; Kaiser, T.E.; Lamont, T.G.; Mulhern, B.M.; Swineford, D.M.

    1977-01-01

    Thirty-nine bald eagles found sick or dead in 13 States during 1969 and 1970 were analyzed for pesticide residues. Residues of DDE, dieldrin, polychlorinated biphenyls (PCB's), and mercury were detected in all bald eagle carcasses; DDD residues were detected in 38; DDT, heptachlor epoxide, and dichlorobenzophenone (DCBP) were detected less frequently. Six eagles contained possible lethal levels of dieldrin in the brain, and one contained a lethal concentration of DDE (385 ppm) in the brain together with 235 ppm of PCB's. Autopsy revealed that 18 bald eagles were illegally shot; other causes of death were impact injuries, electrocution, emaciation, and infectious diseases.

  5. Nationwide residues of organochlorine pesticides in wings of mallards and black ducks

    USGS Publications Warehouse

    Heath, R.G.

    1969-01-01

    Nationwide monitoring of organochlorine pesticides in wings of more than 24,000 mallards and black ducks bagged during the1965 and 1966 hunting seasons showed DDE to be the predominant residue, followed in order by DDT, DDD, dieldrin, and heptachlor epoxide. Residues were generally highest in wings from the Atlantic and Pacific Flyways, and lowest in the Central Flyway. DDE was reported for every State and was notably high in wings from New Jersey, Massachusetts, Connecticut, Rhode Island, New York, Pennsylvania, Alabama, California, and Utah. Dieldrin residues were prevalent in wings from Arkansas, Texas, Utah, California, and several Stales in the Atlantic Flyway.

  6. Problems of positive list system revealed by survey of pesticide residue in food.

    PubMed

    Iwasaki, Mariko; Sato, Itaru; Jin, Yihe; Saito, Norimitsu; Tsuda, Shuji

    2007-05-01

    The positive list system became effective from May 29, 2006 to improve the regulation of residual agricultural chemicals (pesticides, feed additives and veterinary drugs) in foods. In accordance with the system, we investigated pesticide residues in 50 agricultural products purchased in Morioka city from March to November 2006. Analyses were performed according to the "Multiresidue Method for Agricultural Chemicals by GC/MS", the Notice of the Ministry of Health, Labour and Welfare. Five pesticides and two non-agricultural chemicals were detected from 16 samples. Ortho-phenylphenol (OPP) was detected from 8 samples: immature pea, snap bean, kiwi, plain-boiled bamboo shoot, mango, white asparagus, lemon and domestic shiitake mushroom. Maximum residue limits (MRLs) have not been established for these products, and they exceeded the uniform level of 0.01 ppm. DDT was detected from Philippines banana (0.30 ppm) and Korean paprika (0.45 ppm). The residual level in Philippines banana was lower than the MRL, but Korean paprika exceeded its MRL. Chlorpyrifos, Thiabendazole and Imazaril were detected from citrus imported from the U.S.A., but their residue levels were lower than the respective MRLs. Aniline and 2-pyrrolidone were detected from several imported products. These two may not be regulated by the positive list system because they are not agricultural chemicals, although their derivatives are used as pesticides or veterinary drugs. Three problems have been revealed from this survey: 1) application of the uniform level to minor agricultural products, 2) residues of non-agricultural chemicals whose toxicity is uncertain, 3) metabolites of agricultural chemicals, which are also regulated by the positive list system, have not been clearly defined. PMID:17538241

  7. Pesticides

    MedlinePlus

    ... or cause harm to crops, people, or animals. Pesticides can help get rid of them. Pesticides are not just insect killers. They also include ... mildew, germs, and more. Many household products contain pesticides. Pesticides can protect your health by killing germs, ...

  8. Organophosphorus Insecticide Pharmacokinetics

    SciTech Connect

    Timchalk, Charles

    2010-01-01

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

  9. Evaluating spray adjuvants to extend residual activity of microbiol pesticides`

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on requests to improve the residual efficacy of baculovirus applications, a commercial adjuvant (Nu-Film 17(R) and an experimental lignin adjuvant were evaluated for resistance to environmental degradation. Nu-Film is a commercial product derived from pine resin; and lignin is a by-product of...

  10. Extraction and clean-up procedure for analysis of organochlorine pesticide residues in ethoxylated lanolin.

    PubMed

    Polese, L; Sannomiya, M; de Olivera Sader, A P; Lúcia Ribeiro, M

    2000-01-01

    In the present study an evaluation was made of a method for the determination of organochlorine pesticide residues in ethoxylated lanolin. Samples were homogenized with Celite, transferred to chromatographic columns, prepacked with silica gel deactivated to 10%. The pesticide elution was processed with n-hexane-dichloromethane and the concentrated eluate was analyzed using gas-liquid chromatography (GC) with electron capture detection (ECD). The composition of the elution solvent was a significant factor for the recovery of the pesticides. Mean recoveries obtained for fortified samples ranged from 87 to 94% for p,p'-DDE, dieldrin, endrin, p,p'-DDD and p,p'-DDT. Optimization of the experimental conditions resulted in a small-scale method that combines extraction and cleanup in a single step. PMID:11152246

  11. Assessmet of temporal distribution of pesticide residues in vineyard soils of La Rioja (Spain)

    NASA Astrophysics Data System (ADS)

    Pose Juan, Eva; Herrero Hernandez, Eliseo; Soledad Andrades, Maria; Rodriguez Cruz, Maria Sonia; Sanchez Martin, Maria Jesus

    2013-04-01

    The use and application of pesticides in vineyard is a common practice, which is important to prevent pest and diseases and improve the crop health and production, but on the other hand it could involve a potential risk for humans and the environment. For this reason, it is important to develop and validate a simple and fast multiresidue method to determine the presence of these compounds in soils. La Rioja region (Spain) is one of the most important wine-growing regions in Spain, which also entails that could be an important area of pesticide pollution. The objective of this work is to assess the temporal distribution of the possible pesticide pollution in soils from different areas of La Rioja (Spain). The pesticides selected in this study included fungicides (metalaxyl, and its metabolite CGA62826, pyrimethanil, tebuconazole, myclobutanil, kresoxim-methyl, triadimenol and flutriafol); herbicides (fluometuron, terbuthylazine and its metabolites desethylterbuthylazine and hydroxyterbuthylazine, lenacil, ethofumesate and acetochlor) and insecticides (methoxyfenozide and pirimicarb). The pesticide residues were evaluated by two analytical techniques, gas chromatography and liquid chromatography (GC-MS and LC-MS). The extraction procedure of pesticides from soils was optimized using two soil samples (blank soils) with different texture and characteristics collected from areas without pesticide application. Recoveries were studied in soil samples fortified with all pesticides at two levels of concentrations (the agronomic dose, 0.1 mg kg-1, and ten times this dose, 1 mg kg-1). Different extraction solvents were tested. The best results were obtained with methanol:acetone (50:50) mixture or methanol:CaCl2 0.01 M (50:50) mixture for hydroxyterbuthylazine and CGA62826. The accuracy (average recovery) and precision (reproducibility and repeatability) of the method were assessed using six replicates and the limits of detection (LODs) and quantification (LOQs) were

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

    PubMed

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

    2016-04-01

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

  13. Comparison of the variability in the levels of pesticide residue observed in Japanese cabbage and grape units.

    PubMed

    Fujita, Masahiro; Yajima, Tomonari; Iijima, Kazuaki; Sato, Kiyoshi

    2012-02-15

    To estimate variations in pesticide residue levels in crops, the variability factors (VFs, the 97.5th percentile of the residue levels in the sample divided by the average residue levels in the lot) in residue levels of acetamiprid and cypermethrin applied to cabbage and grapes were investigated, respectively. The VFs in the residue levels of both pesticides in cabbage (2.00 and 2.39, respectively) were clearly higher than those in grapes (1.82 and 1.63, respectively). Although the residue levels of both pesticides in grapes showed a normal distribution, those values in cabbage were slightly skewed at lower residue levels. Individual residue levels in grapes had a good agreement between acetamiprid and cypermethrin. In contrast, the distribution of cypermethrin residue levels in cabbage was slightly skewed at higher residue levels as compared to that of acetamiprid. These results indicate that the difference in the relative distribution of the two pesticides between cabbage and grapes might be due to the influence of various factors such as differences in crop species, plant cultivation methods, and physicochemical properties of the pesticides. PMID:22263932

  14. Guidelines for the validation of qualitative multi-residue methods used to detect pesticides in food.

    PubMed

    Mol, H G J; Reynolds, S L; Fussell, R J; Stajnbaher, D

    2012-08-01

    There is a current trend for many laboratories to develop and use qualitative gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) based multi-residue methods (MRMs) in order to greatly increase the number of pesticides that they can target. Before these qualitative MRMs can be used for the monitoring of pesticide residues in food, their fitness-for-purpose needs to be established by initial method validation. This paper sets out to assess the performances of two such qualitative MRMs against a set of parameters and criteria that might be suitable for their effective validation. As expected, the ease of detection was often dependent on the particular pesticide/commodity combinations that were targeted, especially at the lowest concentrations tested (0.01 mg/kg). The two examples also clearly demonstrated that the percentage of pesticides detected was dependent on many factors, but particularly on the capabilities of the automated software/library packages and the parameters and threshold settings selected for operation. Another very important consideration was the condition of chromatographic system and detector at the time of analysis. If the system was relatively clean, then the detection rate was much higher than if it had become contaminated over time from previous injections of sample extracts. The parameters and criteria suggested for method validation of qualitative MRMs are aimed at achieving a 95% confidence level of pesticide detection. However, the presence of any pesticide that is 'detected' will need subsequent analysis for quantification and, depending on the qualitative method used, further evidence of identity. PMID:22851355

  15. Evaluation of two fast and easy methods for pesticide residue analysis in fatty food matrixes.

    PubMed

    Lehotay, Steven J; Mastovská, Katerina; Yun, Seon Jong

    2005-01-01

    Two rapid methods of sample preparation and analysis of fatty foods (e.g., milk, eggs, and avocado) were evaluated and compared for 32 pesticide residues representing a wide range of physicochemical properties. One method, dubbed the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for pesticide residue analysis, entailed extraction of 15 g sample with 15 mL acetonitrile (MeCN) containing 1% acetic acid followed by addition of 6 g anhydrous magnesium sulfate and 1.5 g sodium acetate. After centrifugation, 1 mL of the buffered MeCN extract underwent a cleanup step (in a technique known as dispersive solid-phase extraction) using 50 mg each of C18 and primary secondary amine sorbents plus 150 mg MgSO4. The second method incorporated a form of matrix solid-phase dispersion (MSPD), in which 0.5 g sample plus 2 g C18 and 2 g anhydrous sodium sulfate was mixed in a mortar and pestle and added above a 2 g Florisil column on a vacuum manifold. Then, 5 x 2 mL MeCN was used to elute the pesticide analytes from the sample into a collection tube, and the extract was concentrated to 0.5 mL by evaporation. Extracts in both methods were analyzed concurrently by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry. The recoveries of semi-polar and polar pesticides were typically 100% in both methods (except that basic pesticides, such as thiabendazole and imazalil, were not recovered in the MSPD method), but recovery of nonpolar pesticides decreased as fat content of the sample increased. This trend was more pronounced in the QuEChERS method, in which case the most lipophilic analyte tested, hexachlorobenzene, gave 27 +/- 1% recovery (n=6) in avocado (15% fat) with a<10 ng/g limit of quantitation. PMID:15859091

  16. High level expression of organophosphorus hydrolase in Pichia pastoris by multicopy ophcM assembly.

    PubMed

    Shen, Wei; Shu, Min; Ma, Lixin; Ni, Hong; Yan, Hong

    2016-03-01

    The residues of organophosphorus pesticides bring serious impact on the environmental safety and people's health. Biodegradation of organophosphorus pesticides is recognized as an ideal method. An organophosphorus hydrolase (OPHCM) from Pseudomonas pseudoalcaligenes was synthesized and expressed in Pichia pastoris. The yield reached approximately 470 mg/l after a 6-d induction in shake flasks. To improve the enzyme production, we describe a novel approach to express OPHCM efficiently with a biobrick assembly method in vitro. Four recombinant plasmids containing 1-4 copies of ophcM-expressing cassettes were constructed and transformed into P. pastoris. Increasing the copy number of ophcM gene enhanced the expression level of OPHCM. The maximum yield and specific activity in P. pastoris harboring two-copy tandem ophcM-expressing cassettes reached 610 mg/l after a 6-d induction in shake flasks and 7.8 g/l in high-density fermentation with specific activity of 13.7 U/mg. The optimum pH and temperature of the recombinant OPHCM activity were 11.0 and 50 °C, respectively. In addition, the enzyme activity of recombinant OPHCM enhanced 57.6% and 30.1% in the presence of 1 mM Cd(2+) and 5% glycerol, respectively. The high expression and good properties of recombinant OPHCM provide an effective solution to solve the pollution of organophosphorus pesticides in the environment. Moreover, the approach for generating multicopy gene expressing vectors here will benefit the study for enhancing the expression level of genes of interest. PMID:26611611

  17. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils.

    PubMed

    Centofanti, Tiziana; McConnell, Laura L; Chaney, Rufus L; Beyer, W Nelson; Andrade, Natasha A; Hapeman, Cathleen J; Torrents, Alba; Nguyen, Anh; Anderson, Marya O; Novak, Jeffrey M; Jackson, Dana

    2016-03-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18-39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations. PMID:26716732

  18. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    USGS Publications Warehouse

    Centofantia, Tiziana; McConnell, Laura L.; Chaney, Rufus L.; Beyer, W. Nelson; Andradea, Natasha A.; Hapeman, Cathleen J.; Torrents, Alba; Nguyen, Anh; Anderson, Marya O.; Novak, J. M.; Jackson, Dana

    2015-01-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18–39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.

  19. Development of methodology for determination of pesticides residue in water by SPE/HPLC/DAD.

    PubMed

    Cappelini, Luciana Teresa Dias; Cordeiro, Daniela; Brondi, Silvia Helena Govoni; Prieto, Kátia Roberta; Vieira, Eny Maria

    2012-01-01

    To boost crop yield, sugarcane growers are using increasing amounts of pesticides to combat insects and weeds. But residues of these compounds can pollute water resources, such as lakes, rivers and aquifers. The present paper reports the results of a study of water samples from the Feijão River, which is the source of drinking water for the city of São Carlos, São Paulo, Brazil. The samples were evaluated for the presence of four leading pesticides--ametryn, atrazine, diuron and fipronil--used on sugarcane, the dominant culture in the region. The samples were obtained from three points along the river: the headwaters, along the middle course of the river and just before the municipal water intake station. The pesticides were extracted from the water samples by solid-phase extraction (SPE) and then analyzed by liquid chromatography with diode array detection (LC-DAD). The analytical method was validated by traditional methods, obtaining recovery values between 90 and 95%, with precision deviations inferior to 2.56%, correlation coefficients above 0.99 and detection and quantification limits varying from 0.02 to 0.05 mg L(-1) and 0.07 to 0.17 mg L(-1), respectively. No presence of residues of the pesticides was detected in the samples, considering the detection limits of the method employed. PMID:23393971

  20. Effect of sampling size on the determination of accurate pesticide residue levels in Japanese agricultural commodities.

    PubMed

    Fujita, Masahiro; Yajima, Tomonari; Iijima, Kazuaki; Sato, Kiyoshi

    2012-05-01

    The uncertainty in pesticide residue levels (UPRL) associated with sampling size was estimated using individual acetamiprid and cypermethrin residue data from preharvested apple, broccoli, cabbage, grape, and sweet pepper samples. The relative standard deviation from the mean of each sampling size (n = 2(x), where x = 1-6) of randomly selected samples was defined as the UPRL for each sampling size. The estimated UPRLs, which were calculated on the basis of the regulatory sampling size recommended by the OECD Guidelines on Crop Field Trials (weights from 1 to 5 kg, and commodity unit numbers from 12 to 24), ranged from 2.1% for cypermethrin in sweet peppers to 14.6% for cypermethrin in cabbage samples. The percentages of commodity exceeding the maximum residue limits (MRLs) specified by the Japanese Food Sanitation Law may be predicted from the equation derived from this study, which was based on samples of various size ranges with mean residue levels below the MRL. The estimated UPRLs have confirmed that sufficient sampling weight and numbers are required for analysis and/or re-examination of subsamples to provide accurate values of pesticide residue levels for the enforcement of MRLs. The equation derived from the present study would aid the estimation of more accurate residue levels even from small sampling sizes. PMID:22475588

  1. Pesticide residue analysis in parsley, lettuce and spinach by LC-MS/MS.

    PubMed

    Esturk, Okan; Yakar, Yasin; Ayhan, Zehra

    2014-03-01

    In this study, pesticide residues in parsley, lettuce and spinach (120 samples) were analyzed by the application of liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples of spinach, parsley or lettuce contained residues of three or more active substances. In parsley, carbendazim (100.0%), dichlorvos (100.0%), fenarimol (40.0%), pendimethalin (95.0%), in lettuce, diazinon (30.0%), dichlorvos (100.0%), pendimethalin (92.5%) phenthoate (12.5%), and in spinach, carbendazim (45.0%), cymoxanil (85.0%), dichlorvos (100.0%) and fenarimol (85.0%) were the significant active compounds. The maximum residue limits were exceeded in 28, 20 and 40 samples of parsley, lettuce and spinach, respectively. The results showed that there was a high occurrence of pesticide residues in parsley, lettuce and spinach samples from Hatay province, in which most of them were prohibited from use in Turkey for these vegetables. The contamination levels of these residues may be considered a serious public health problem according to the maximum residue limits (MRLs) of Turkey and the European Union (EU). PMID:24587520

  2. LITERATURE REVIEW AND EVALUATION OF THE EPA FOOD-CHAIN (KENAGA) NOMOGRAM, AN INSTRUMENT FOR ESTIMATING PESTICIDE RESIDUES ON PLANTS

    EPA Science Inventory

    The Kenaga nomogram is a simple device developed by the U.S. Environmental Protection Agency (EPA) in the early 1980s and is currently used to predict the maximum potential pesticide residue levels in the food chain of wildlife before pesticide registration. o evaluate the accura...

  3. 75 FR 53690 - Notice of Receipt of Pesticide Petition Filed for Residues of Potassium Peroxymonosulfate in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... AGENCY Notice of Receipt of Pesticide Petition Filed for Residues of Potassium Peroxymonosulfate in or on... regulations for residues of potassium peroxymonosulfate in or on various commodities. DATES: Comments must be... the requirement of a tolerance for residues of the antimicrobial, potassium peroxymonosulfate, in...

  4. Nucleotide sequence of a gene encoding an organophosphorus nerve agent degrading enzyme from Alteromonas haloplanktis.

    PubMed

    Cheng, T; Liu, L; Wang, B; Wu, J; DeFrank, J J; Anderson, D M; Rastogi, V K; Hamilton, A B

    1997-01-01

    Organophosphorus acid anhydrolases (OPAA) catalyzing the hydrolysis of a variety of toxic organophosphorus cholinesterase inhibitors offer potential for decontamination of G-type nerve agents and pesticides. The gene (opa) encoding an OPAA was cloned from the chromosomal DNA of Alteromonas haloplanktis ATCC 23821. The nucleotide sequence of the 1.7 -kb DNA fragment contained the opa gene (1.3 kb) and its flanking region. We report structural and functional similarity of OPAAs from A. haloplanktis and Alteromonas sp JD6.5 with the enzyme prolidase that hydrolyzes dipeptides with a prolyl residue in the carboxyl-terminal position. These results corroborate the earlier conclusion that the OPAA is a type of X-Pro dipeptidase, and that X-Pro could be the native substrate for such an enzyme in Alteromonas cells. PMID:9079288

  5. Pesticide residues in tobacco leaves from the Kushtia district in Bangladesh.

    PubMed

    Rahman, Mohammad Abdur; Chowdhury, Alamgir Zaman; Moniruzzaman, Mohammed; Gan, Siew Hua; Islam, Mohammad Nazrul; Fardous, Zeenath; Alam, Mohammad Khorshed

    2012-09-01

    In this study, tobacco leaf samples (n = 26) were collected from different areas in Kushtia to determine the presence of residues of cypermethrin, diazinon, heptachlor, methoxychlor dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethan (DDD) and dichlorodiphenyldichloroethylene (DDE). The analysis was conducted by a High Performance Liquid Chromatography (HPLC) system that was equipped with a photodiode array detector. Both cypermethrin and diazinon were detected in tobacco samples from six districts, namely, Mirzapur, Shahebnagar, Kodalipara, Pragpur, Farakpur and Taragunia. The highest concentration of cypermethrin was found in Kodalipara (2.00 ppm) while the highest concentration of diazinon was detected in a sample from Pragpur (0.15 ppm). The pesticide DDT was only detected in the sample from Pragpur at 4.00 ppm. This is the first study in Bangladesh that reports pesticide residue concentrations in tobacco leaf samples. PMID:22782359

  6. 75 FR 1773 - Notice of Receipt of a Pesticide Petition Filed for Residues of Polymeric Polyhydroxy Acid in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ...This notice announces the Agency's receipt of an initial filing of a pesticide petition proposing the establishment of a regulation for residues of the plant growth regulator, polymeric polyhydroxy acid, in or on all food...

  7. Extraction and detection of pesticide residues from air filter inserts using supercritical carbon dioxide

    SciTech Connect

    Zemanian, T.S.; Robins, W.H.; Lee, R.N.; Wright, B.W.

    1994-10-01

    Trace quantities of airborne herbicide residues were collected on adsorbent bed cartridges and were subsequently extracted from the adsorbent using supercritical carbon dioxide. An apparatus was constructed to facilitate the extraction and recovery of the desired analytes. The resulting extracts were analyzed using gas chromatography/mass spectrometry (GC/MS) or high performance liquid chromatography (HPLC) techniques. Results are presented for a series of analytes representative of common commercial pesticides or herbicides.

  8. Persistent organochlorine pesticide residues in fish, sediments and water from Lake Bosomtwi, Ghana.

    PubMed

    Darko, Godfred; Akoto, Osei; Oppong, Caleb

    2008-05-01

    Some organochlorine pesticide residues in tilapia fish (Tilapiazilli), sediment and water samples from Lake Bosomtwi (the largest natural lake in Ghana) were determined to find out the extent of pesticide contamination and accumulation in the lake. The extracted residues were analyzed on a micro-capillary gas chromatograph equipped with electron capture detector. DDE (p,p'-1,1-dichloro-2,2-bis-(4-chlorophenyl)ethylene) was the predominant residue in all the samples analyzed; detected in 82% of water samples, 98% of sediment samples and 58% of fish samples at concentrations of 0.061+/-0.03 ng g(-1), 8.342+/-2.96 ng g(-1) and 5.232+/-1.30 ng g(-1), respectively. DDT (p,p'-1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane) was detected in 78% at a mean concentration 0.012+/-0.62 ng g(-1) of water samples analyzed. The mean concentrations of DDT in sediments and fish were 4.41+/-1.54 ng g(-1) and 3.645+/-1.81 ng g(-1), respectively. The detection of lower levels of DDT than its metabolite, DDE, in the samples implies that the presence of these contaminants in the lake is as result of past usage of the pesticides. PMID:18397799

  9. The effect of pesticide residue on caged mosquito bioassays.

    PubMed

    Barber, J A S; Greer, Mike; Coughlin, Jamie

    2006-09-01

    Wind tunnel experiments showed that secondary pickup of insecticide residue by mosquitoes in cage bioassays had a significant effect on mortality. Cage bioassays using adult Ochlerotatus taeniorhynchus (Wiedemann) investigated the effect of exposure time to a contaminated surface. Cages were dosed in a wind tunnel using the LC50 for naled (0.124 mg a.i./ml) and an LC25 (0.0772 mg a.i./ml) for naled. Half of the bioassay mosquitoes were moved directly into clean cages with the other half remaining in the sprayed, hence contaminated, cage. Treatment mortality was assessed at 8, 15, 30, 60, 120, 240, and 1,440 min postapplication. Cage contamination had a significant effect on mosquito mortality for both the LC25 and LC50 between 15 and 30 min postapplication. PMID:17067048

  10. Does further clean-up reduce the matrix enhancement effect in gas chromatographic analysis of pesticide residues in food?

    PubMed

    Schenck, F J; Lehotay, S J

    2000-01-28

    Sample extracts of apples, peas, green beans, oranges, raspberries, clementines, carrots, and wheat obtained using the Food and Drug Administration (acetone extraction) and Canadian Pest Management Regulatory Agency (acetonitrile extraction) multiresidue methods for pesticides were subjected to clean-up using different solid-phase extraction (SPE) cartridges in an attempt to reduce or eliminate the matrix enhancement effect. The matrix enhancement effect is related to the blocking of active sites on the injector liner by matrix components, thereby increasing signal in the presence of matrix versus standards in solvent in which the pesticides themselves interact with the active sites. Graphitized carbon black (GCB) was often used in combination with various anion-exchange SPE cartridges. The extracts were then spiked with organophosphorus insecticides. These process standards were then compared to standards in acetone of the same concentration using gas chromatography with flame photometric detection or ion trap mass spectrometric detection. Sample matrix enhancement varied from little to no effect for some pesticides (e.g. chlorpyrifos, malathion) to >200% in the case of certain susceptible pesticides. The GCB removed color components but showed little effect in reducing matrix enhancement by itself. The anion-exchange cartridges in combination with GCB or not, substantially reduced the matrix enhancement effect but did not eliminate it. PMID:10677079

  11. Safe apples for baby-food production: survey of pesticide treatment regimes leaving minimum residues.

    PubMed

    Ticha, Jana; Hajslova, Jana; Kovalczuk, Tomas; Jech, Martin; Honzicek, Jiri; Kocourek, Vladimir; Lansky, Miroslav; Kloutvorova, Jana; Falta, Vladan

    2007-06-01

    A total of 19 pesticide preparations were used according to agricultural practice in six trials in apple orchards. Using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), premature Golden Delicious apples collected 64, 50, 36 days before harvest and mature fruit were examined for residues of active ingredients. No residues of triflumuron, triazamate, chlorpyrifos, etofenprox, fenoxycarb, kresoxim-methyl, cyprodinyl, difenoconazole or thiram were detected in the first sampling. Also, the levels of chlorpyrifos-methyl, penconazole, tebuconazole and tolylfluanid dropped during the pre-harvest interval. Detectable residues of pyridaben, thiacloprid, trifloxystrobin and tetraconazole in harvested fruits were below 0.01 mg kg(-1), which is the maximum concentration of residues acceptable by baby-food producers in any raw material. The only residues exceeding this concentration were captan and teflubenzuron. Based on the data, farmers can choose pesticides for optimal treatment of plants, while enabling growth of a safe crop suitable for baby-food production. PMID:17487602

  12. Determination of pesticide residues in integrated pest management and nonintegrated pest management samples of apple (Malus pumila Mill.).

    PubMed

    Singh, Shashi Bala; Mukherjee, Irani; Maisnam, Jaya; Kumar, Praveen; Gopal, Madhuban; Kulshrestha, Gita

    2009-12-01

    Studies were undertaken to analyze the residues of commonly used pesticides viz. chlorpyrifos, endosulfan, dicofol, cypermethrin, fenvalerate, propargite, malathion, phorate, carbendazim, carbosulfan, thiamethoxam, and mancozeb in apple of integrated pest management (IPM) and non-IPM samples collected from the IPM and non-IPM fields of Shimla. We also present a method for the determination of these pesticides in apple samples. Residues of chlorpyrifos, endosulfan, dicofol, cypermethrin, fenvalerate, and propargite were analyzed by gas chromatography, while residues of carbendazim, carbosulfan, and thiamethoxam were analyzed by high-performance liquid chromatography. Residues of mancozeb were determined by a colorimetric method. Recoveries of all of the pesticides ranged from 61.30 to 95.46% at 0.1, 0.2, and 1.0 microg g(-1) levels of fortification with relative standard deviations ranging between 0.8 and 8.7. Apples from IPM and non-IPM orchards were analyzed for these pesticides using a developed method. Except for carbendazim and chlorpyrifos, the residues of all of the pesticides analyzed were below detectable limits. Although residues of carbendazim and chlorpyrifos were below the prescribed limits of maximum residue levels in both IPM and non-IPM orchards, residues were lower in apples from IPM orchards. PMID:19904932

  13. Residues of organochlorine pesticides and polycyclic aromatic hydrocarbons in drinking water of Ahmedabad City, India

    SciTech Connect

    Jani, J.P.; Mistry, J.S. ); Raiyani, C.V.; Patel, J.S.; Desai, N.M.; Kashyap, S.K. )

    1991-09-01

    The ubiquitous environmental pollutants organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) have been extensively studied for their toxicity. Monitoring of OCP and PAH residues has always been considered important for controlling human exposure. As compared to several other countries, the higher body burden of OCP in Indian general population is indicative of higher exposure to these chemicals. Recent studies have shown higher residues of OCP in food commodities including human mother's milk. The levels of OCP in drinking water is still a matter of concern and practically nothing is known about the residues of PAH in drinking water in India. This is the first report of its kind regarding the residues of OCP and PAH in drinking water of Ahmedabad City, the sixth largest city of India with a population of more than 2.5 million.

  14. Concentrations of pesticide residues in tissues of fish from Kolleru Lake in India.

    PubMed

    Amaraneni, S R; Pillala, R R

    2001-01-01

    Kolleru Lake is the largest natural freshwater lake of Andhra Pradesh in India. It is situated between latitudes 16 degrees 32' and 16 degrees 47'N and longitudes 81 degrees 05' and 81 degrees 27'E. The use of pesticides for agricultural purposes is widespread in the Kolleru Lake region. The biological indicators like fish help in the studies of aquatic pollution by pesticides. Fish species Channa striata and Catla catla and water samples were collected from Kolleru Lake in each of three seasons over a period of three years. Fish samples were analyzed according to a modified method which is proposed for the gas chromatographic determination for the pesticides viz., alpha-BHC, gamma-BHC, malathion, chloirpyrifos, isodrin, endosulfan, dieldrin, and p,p-DDT. Water samples were analyzed for selected physico-chemical parameters. The extraction efficiency for the selected pesticides is between 82.8% and 91.2%. The maximum concentrations of pesticide residues in Kolleru Lake fish on wet weight basis are 123.8 micrograms/g for alpha-BHC, 98.7 micrograms/g for gamma-BHC, 2.5 micrograms/g for malathion, 88.6 micrograms/g for chlorpyrifos, 0.91 microgram/g for isodrin, 76.5 micrograms/g for endosulfan, 1.98 micrograms/g for dieldrin, and 157.4 micrograms/g for p,p'-DDT. These analyses were used to evaluate the baseline data and the pesticide pollution in the lake's ecosystem. PMID:11769254

  15. Effect of Chinese traditional cooking on eight pesticides residue during cowpea processing.

    PubMed

    Huan, Zhibo; Xu, Zhi; Jiang, Wayne; Chen, Zhiqiang; Luo, Jinhui

    2015-03-01

    Thermal processing can concentrate residues or convert residues to more toxic metabolites in food. Chinese traditional cooking pays more attention to thermal processing and more vegetables were eaten after thermal processing. In this study, the effect of Chinese traditional cooking (washing, blanching, stir-frying, frying and combined operations) on eight pesticides residues (pyridaben, procymidone, chlorothalonil, difenoconazole, α-cypermethrin, bifenthrin, S-fenvalerate and λ-cyhalothrin) in cowpea which was one of the most important legume crops in China was examined. Result showed washing and blanching could reduce residues with low Kow while stir-frying and frying were more effective to residues with high Kow; stir-frying and frying could concentrate residues with low Kow; the residue levels in oil increased following increasing frying time and frequency especially the residues with high Kow; one metabolite studied in this paper was not detected. Blanching (5 min) followed by stir-frying (3 min) was the most effective combined operation. PMID:25306325

  16. Selective, solid-matrix dispersion extraction of organophosphate pesticide residues from milk.

    PubMed

    Di Muccio, A; Pelosi, P; Camoni, I; Attard Barbini, D; Dommarco, R; Generali, T; Ausili, A

    1996-11-22

    A rapid procedure has been developed that allows a single-step, selective extraction and cleanup of organophosphate (OP) pesticide residues from milk dispersed on solid-matrix diatomaceous material filled into disposable cartridges by means of light petroleum saturated with acetonitrile and ethanol. Recovery experiments were carried out on homogenized commercial milk (3.6% fat content) spiked with ethanolic solutions of 24 OP pesticides, viz., ethoprophos, diazinon, dimethoate, chlorpyrifos-methyl, parathion-methyl, chlorpyrifos-ethyl, malathion, isofenphos, quinalphos, ethion, pyrazophos, azinphosethyl, heptenophos, omethoate, fonofos, pirimiphos-methyl, fenitrothion, parathion, chlorfenvinphos, phenthoate, methidathion, triazophos, phosalone, azinphos-methyl, at levels ranging for the different OP pesticides from 0.02 mg/kg to 1.11 mg/kg. Average recoveries of four replicates were in the range 72-109% for the different OP pesticides, with relative standard deviations (R.S.D.) from ca. 1 to 19%, while dimethoate and omethoate were not recovered. Coextracted fatty material amounted to an average of about 4.0 mg/ml of milk. The extraction procedure requires about 30 min. The main advantages are that extraction and cleanup are carried out in a single step, emulsions do not occur, several samples can be run in parallel by a single operator, reusable glassware is not needed and simple operations are required. PMID:8997741

  17. Multiresidue determination of pesticides in lanolin using matrix solid-phase dispersion.

    PubMed

    Pérez, Andrés; González, Gabriel; González, Joaquín; Heinzen, Horacio

    2010-01-01

    An efficient, fast, and accurate matrix solid-phase dispersion sample cleanup procedure was developed specifically for the determination of pesticide residues in lanolin. The scope of the method for organophosphorus, organochlorine, and pyrethroid insecticides is the same as that of official methods from various pharmacopeias. After lanolin dispersion on C18 bonded silica, pesticides are eluted with acetonitrile saturated with n-hexane. Recoveries ranged from 83 to 118% with RSD values of < 20% for most pesticides listed, in compliance with the requirements of European and U.S. pharmacopeias. PMID:20480919

  18. De-contamination of pesticide residues in food by ionizing radiation

    NASA Astrophysics Data System (ADS)

    Basfar, Ahmed A.; Mohamed, Khaled A.; Al-Saqer, Omar A.

    2012-04-01

    The role of gamma irradiation on removal of pesticides in aqueous solutions or in vegetables and fruits was investigated. Radiation - induced decontamination of pesticides is generally greater in aqueous solutions than in selected vegetables and fruits. Residues of malathion (0.5 ppm in potatoes, 8 ppm in onions and dates), pirimiphos-methyl (1 ppm in onions and grapes) and cypermethrin (0.05 ppm in potatoes and 0.1 ppm in onions) were not reduced to below maximum residue limits (MRLs) for irradiation doses up to 1 kGy. The same trend was observed when irradiation was performed for grapes fortified with malathion (8 ppm) and cypermethrin (2 ppm) for absorbed doses up to 2 kGy. Ionizing radiation reduced the residues of pirimiphos-methyl (0.05 ppm in potatoes at1 kGy, 1 ppm in grapes at 2 kGy and 0.1 ppm in dates at1 kGy), malathion (8 ppm in grapes at 7 kGy) and cypermethrin (2 ppm in grapes at 7 kGy) to below maximum residue limits (MRLs).

  19. Pesticide residues in some herbs growing in agricultural areas in Poland.

    PubMed

    Malinowska, Elżbieta; Jankowski, Kazimierz

    2015-12-01

    The aim of this paper was to assess residue content of plant protection products in selected herbs: Achillea millefolium L., Cichorium intybus L., Equisetum arvense L., Polygonum persicaria L., Plantago lanceolata L., and Plantago major L. The study comprises herbs growing in their natural habitat, 1 and 10 m away from crop fields. The herbs, 30 plants of each species, were sampled during the flowering stage between 1 and 20 July 2014. Pesticide residue content was measured with the QuECHERS method in the dry matter of leaves, stalks, and inflorescence, all mixed together. Out of six herb species growing close to wheat and maize fields, pesticide residues were found in three species: A. millefolium L., E. arvense L., and P. lanceolata L. Most plants containing the residues grew 1 m away from the wheat field. Two active substances of fungicides were found: diphenylamine and tebuconazole, and one active substance of insecticides: chlorpyrifos-ethyl. Those substances are illegal to use on herbal plants. Samples of E. arvense L. and P. lanceolata L. contained two active substances each, which constituted 10% of all samples, while A. millefolium L. contained one substance, which is 6.6% of all samples. PMID:26612566

  20. Contributions of pesticide residue chemistry to improving food and environmental safety: past and present accomplishments and future challenges.

    PubMed

    Seiber, James N; Kleinschmidt, Loreen A

    2011-07-27

    The principles of modern pesticide residue chemistry were articulated in the 1950s. Early authors pointed out the advantages of systematizing and standardizing analytical methods for pesticides so that they could be widely practiced and the results could be reproduced from one laboratory to the next. The availability of improved methods has led to a much more complete understanding of pesticide behavior and fate in foods and the environment. Using methods based largely upon gas chromatography (GC) and high-performance liquid chromatography (HPLC) coupled increasingly with mass spectrometry (MS) and MS(n) as the detection tool, residues can be measured at parts per billion levels and below in a variety of food and environmental matrices. Development of efficient extraction and cleanup methods, techniques such as ELISA, efficient sample preparation techniques such as QuEChERS, and automated laboratory and field instrumentation has also contributed to the tools available for use in modern pesticide residue analysis. As a result, great strides have been made in improving food and worker safety and in understanding environmental behavior and fate of pesticides. There are many challenges remaining in the field of pesticide residue chemistry that will continue to stimulate analytical chemists. New chemistries are emerging, often patterned on complex natural products. Analyzing for the parent chemicals and potentially multiple breakdown products will require analytical ingenuity. The development of more sensitive bioassays and knowledge of unintended side effects will challenge residue chemistry as well, as in the case of following the fate of environmental endocrine disruptors associated with some pesticides as well as nonpesticide contaminants from packaging materials and other familiar articles. Continued funding and other resources to ensure better training, international cooperation, and accelerated research and development activities will be a constant need in

  1. High-Throughput Analytical Techniques for Determination of Residues of 653 Multiclass Pesticides and Chemical Pollutants in Tea, Part VI: Study of the Degradation of 271 Pesticide Residues in Aged Oolong Tea by Gas Chromatography-Tandem Mass Spectrometry and Its Application in Predicting the Residue Concentrations of Target Pesticides.

    PubMed

    Chang, Qiao-Ying; Pang, Guo-Fang; Fan, Chun-Lin; Chen, Hui; Wang, Zhi-Bin

    2016-07-01

    The degradation rate of 271 pesticide residues in aged Oolong tea at two spray concentrations, named a and b (a < b), were monitored for 120 days using GC-tandem MS (GC-MS/MS). To research the degradation trends and establish regression equations, determination days were plotted as horizontal ordinates and the residue concentrations of pesticide were plotted as vertical ordinates. Here, we consider the degradation equations of 271 pesticides over 40 and 120 days, summarize the degradation rates in six aspects (A-F), and discuss the degradation trends of the 271 pesticides in aged Oolong tea in detail. The results indicate that >70% of the determined pesticides coincide with the degradation regularity of trends A, B, and E, i.e., the concentration of pesticide will decrease within 4 months. Next, 20 representative pesticides were selected for further study at higher spray concentrations, named c and d (d > c > b > a), in aged Oolong tea over another 90 days. The determination days were plotted on the x-axis, and the differences between each determined result and first-time-determined value of target pesticides were plotted on the y-axis. The logarithmic function was obtained by fitting the 90-day determination results, allowing the degradation value of a target pesticide on a specific day to be calculated. These logarithmic functions at d concentration were applied to predict the residue concentrations of pesticides at c concentration. Results revealed that 70% of the 20 pesticides had the lower deviation ratios of predicted and measured results. PMID:27151741

  2. Vortex-assisted liquid-liquid microextraction using a low-toxicity solvent for the determination of five organophosphorus pesticides in water samples by high-performance liquid chromatography.

    PubMed

    Peng, Guilong; He, Qiang; Mmereki, Daniel; Zhou, Guangming; Pan, Weiliang; Gu, Li; Fan, Leilei; Tang, Xiaohui; Chen, Junhua; Mao, Yufeng

    2015-10-01

    Vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with UV detection was applied to determine Isocarbophos, Parathion-methyl, Triazophos, Phoxim and Chlorpyrifos-methyl in water samples. 1-Bromobutane was used as the extraction solvent, which has a higher density than water and low toxicity. Centrifugation and disperser solvent were not required in this microextraction procedure. The optimum extraction conditions for 15 mL water sample were: pH of the sample solution, 5; volume of the extraction solvent, 80 μL; vortex time, 2 min; salt addition, 0.5 g. Under the optimum conditions, enrichment factors ranging from 196 to 237 and limits of detection below 0.38 μg/L were obtained for the determination of target pesticides in water. Good linearities (r > 0.9992) were obtained within the range of 1-500 μg/L for all the compounds. The relative standard deviations were in the range of 1.62-2.86% and the recoveries of spiked samples ranged from 89.80 to 104.20%. The whole proposed methodology is simple, rapid, sensitive and environmentally friendly for determining traces of organophosphorus pesticides in the water samples. PMID:26257135

  3. Influence of the nature and age of cover crop residues on the sorption of three pesticides

    NASA Astrophysics Data System (ADS)

    Cassigneul, Ana; Alletto, Lionel; Chuette, Delphine; Le Gac, Anne-Laure; Hatier, Jules; Etievant, Veronique; Bergheaud, Valérie; Baumberger, Stéphanie; Méchin, Valérie; Justes, Eric; Benoit, Pierre

    2013-04-01

    In agricultural fields, soil and water quality preservation is strongly influenced by pesticides use and behavior. To limit the environmental impacts of agricultural activities, best management practices such as the use of cover crops are encouraged. Cover crops during the fallow period were found to be efficient in reducing nitrate leaching, controlling soil erosion, improving soil organic content and enhancing soil biological activity. This technique was also found to modify soil water dynamics in the following crop. According to these effects, modifications on pesticide behavior in soil, such as sorption, degradation and transport, are expected (Alletto et al., 2012 ; 2013). In this study, the impact of the nature and level of decomposition of cover crop was studied on the sorption characteristics of three pesticides. These pesticides differed in their physicochemical characteristics (hydrophobicity, solubility, persistence) and were two herbicides, S-metolachlor and glyphosate, which are largely used in maize production and predominantly found as pollutants in water; and one fungicide, epoxiconazole. Correlations between pesticide sorption and physicochemical characteristics of the cover crop residues were studied. Residues of oat, turnip rape, red clover and phacelia were collected in March 2011 and incubated at 28°C and at the water holding capacity during 0, 6, 28 or 56 days. For each date, adsorption of the three radiolabeled pesticides was measured in batch on the different cover crop residues, and their biochemical composition (Van Soest fractionation), hydrophobicity (contact angle measurement) and C/N ratio were determined. Results showed that the adsorption of the pesticides differed significantly according to (i) the pesticide, (ii) the nature of cover crop, (iii) the decomposition level of the cover crop and the interaction cover crop x decomposition time. Epoxiconazole was the most adsorbed molecule, with Kd values ranging from 161 ± 30 L/Kg (oat

  4. Residues of organochlorine pesticides in soils from the southern Sonora, Mexico.

    PubMed

    Cantu-Soto, E U; Meza-Montenegro, Maria Mercedes; Valenzuela-Quintanar, A I; Félix-Fuentes, A; Grajeda-Cota, P; Balderas-Cortes, J J; Osorio-Rosas, C L; Acuña-García, G; Aguilar-Apodaca, M G

    2011-11-01

    Although, the Yaqui and Mayo valleys are the most important agricultural areas in Sonora, there is only limited data of the pesticides residue in soils in these valleys. This study measured the organochlorine pesticides (OCPs) in 234 soil samples (residential and agricultural) from 24 communities. The global results (mean, range) indicated that benzene hexachloride (19.2, ND-938.5 μg g(-1)), endrin (6.6, ND-377.3 μg g(-1)) and DDTs (36.45, ND-679.7 μg g(-1)) were the dominant contaminants. Soil is one of the most important routes of exposure to OCPs in the population of southern Sonora and this study can be used to establish background levels of OCPs. PMID:21761173

  5. Organochlorine pesticide residues in blood samples of agriculture and sheep wool workers in Bangalore (rural), India.

    PubMed

    Dhananjayan, V; Ravichandran, B; Rajmohan, H R

    2012-04-01

    To describe exposure level of organochlorine pesticides (OCP) among workers occupationally engaged in agriculture and sheep wool associated jobs, the present study was carried out in rural neighborhood of Bangalore city, India. Thirty participants were interviewed and obtained informed consent before blood sample collection. The maximum concentrations of OCP were detected in blood samples of agriculture workers than sheep wool workers. Among the metabolites of HCH and DDT, lindane (γ-HCH) and p,p'-DDE were the most contributed to the total OCP. There were no differences in pesticide residues found between sex and work groups. It was observed that about 30% of samples exceeded the tolerance limits of 10 μg/L prescribed for HCH under the prevention of food adulteration act. Therefore, the present study recommends continuous monitoring with larger sample size. PMID:22323047

  6. ANALYSIS OF PESTICIDE RESIDUES IN HUMAN AND ENVIRONMENTAL SAMPLES: A COMPILATION OF METHODS SELECTED FOR USE IN PESTICIDE MONITORING PROGRAMS

    EPA Science Inventory

    This manual provides the pesticide chemist with methodology useful in determining human exposure to pesticides and related industrial chemicals. Methods are also presented for measuring the extent of environmental contamination with these compounds. This manual has been compiled ...

  7. Organochlorine pesticide residues in human fat in the United Kingdom 1976-7.

    PubMed Central

    Abbott, D C; Collins, G B; Goulding, R; Hoodless, R A

    1981-01-01

    Between May 1976 and August 1977 samples of human body fat were taken during routine necropsies in the United Kingdom on 236 subjects aged over 5 years and four infants aged under 4 months. Comparison with results from earlier studies showed a further decline in residues of pp'-dichlorodiphenyltrichloroethane (pp'-DDT) and dieldrin (HEOD) and increased amounts of hexachlorobenzene residues; concentrations of other compounds were similar to those observed in the studies carried out in 1963-4, 1965-7, and 1969-71. Comparison of the data with those from other countries, showed that the concentrations of organochlorine pesticide residues and polychlorobiphenyls in human fat samples from residents of the United Kingdom remain among the lowest in Europe and, indeed, the world. PMID:6797569

  8. A novel chemiluminescence assay of organophosphorous pesticide quinalphos residue in vegetable with luminol detection

    PubMed Central

    2010-01-01

    Background Organophosphorous pesticides are the most popular pesticides used in agriculture. As acetylcholinesterase inhibitors, organophosphorous pesticides are toxic organic chemicals. The control and detection of organophosphorous pesticide residue in food, water, and environment therefore plays a very important role in maintaining physical health. A sensitive, rapid, simple chemiluminescence(CL) method has been developed for the determination of quinalphos based on the reaction of quinalphos with luminol-H2O2 in an alkaline medium. The method has been applied to detection of quinalphos in vegetable samples with satisfactory results. Results The CL method for the determination of organophosphorous pesticide quinalphos is based on the phenomenon that quinalphos can apparently enhance the CL intensity of the luminol-H2O2 system. The optimal conditions were: luminol concentration 5.0 × 10-4 mol/L, H2O2 concentration 0.05 mol/L.pH value 13. In order to restrain the interference from metal ions, 1.0 × 10-3 mol/L of EDTA was added to the luminol solution. The possible mechanism was proposed. Conclusion Under the optimum reaction conditions, CL was linear with the concentration of quinalphos in the range of 0.02 μg/mL -1.0 μg/mL and the detection limit was 0.0055 μg/mL (3σ). This method has been successfully applied to the detection of quinalphos in vegetable samples. According to the experimental data, the average recoveries for quinalphos in cherry tomato and green pepper 97.20% and 90.13%. Meanwhile, the possible mechanism was proposed. PMID:20576096

  9. Realistic approach of pesticide residues and French consumer exposure within fruit & vegetable intake.

    PubMed

    Drouillet-Pinard, Peggy; Boisset, Michel; Periquet, Alain; Lecerf, Jean-Michel; Casse, Francine; Catteau, Michel; Barnat, Saida

    2011-01-01

    The increase of fruit and vegetable (F&V) intake contributes to the prevention of chronic diseases, but could also significantly increase pesticide exposure and may thus be of health concern. Following a previous pesticide exposure assessment study, the present study was carried out to determine actual levels of pesticides within 400 g of F&V intake and to evaluate consumer risk. Forty-three Active Substances (AS) exceeding 10 % of the Acceptable Daily Intake (ADI) in balanced menus established for our previous theoretical study were considered. Fifty-six pooled food samples were analyzed: 28 fruit samples and 28 vegetable samples. Pesticide values were compared to Maximum Residue Levels (MRL) and to the "toxicological credit" derived from ADI. It was observed that 23 out of the 43 retained AS were never detected, 5 were detected both in F&V samples, 12 only in fruits and 3 only in vegetables. The most frequently detected AS were carbendazim, iprodione and dithiocarbamates. When detected, AS were more frequently found in fruit samples (74 %) than in vegetable samples (26 %). A maximum of 3 AS were detected at once in a given sample. Overall, we observed 8 and 14 overruns of the MRL in 1204 measures in pooled vegetable and fruit samples, respectively (0.7 % and 1.2 % of cases, respectively). Chronic exposure for adults was the highest for dithiocarbamates but did not exceed 23.7 % of the ADI in F&V. It was concluded that raising both F&V consumption up to 400 g/day (~5 F&V/day) according to recommendations of the national health and nutrition plan, does not induce pesticide overexposure and should not represent a risk for the consumer. PMID:21191868

  10. Organochlorine pesticide residues: an extensive monitoring of Italian fishery and aquaculture.

    PubMed

    Masci, Maurizio; Orban, Elena; Nevigato, Teresina

    2014-01-01

    A sampling campaign from 21 sites in Italy was carried out to investigate the presence of organochlorine pesticide residues in different fish species. Samples came from marine fishery and either from sea- or freshwater aquaculture. Fish feed used in some fish farms were also analyzed. Pesticides studied belong to Persistent Organic Pollutants widely used in the past such as DDT, chlordane, heptachlor, and others. To ensure good quality results and proper data validation the main existing guidelines in the field were applied. The instrumental technique was a Dual column-Dual detector Gas Chromatography (GC-ECD and Ion Trap GC-MS) which allowed that complementary data on the same sample were acquired. Results for fishery showed a wide range of concentrations depending from the area and species examined. DDT, the major OC pesticide detected, varied from 0.02 to 130.03 ng g(-1) edible portion. As regards the products of aquaculture we observed slightly lower average levels of pollutants in a more narrow range of concentration: this is probably due to fish feed used as shown by some measures performed in the present study. Organochlorine pesticide residues were detected in all samples examined but they were generally well below the existing tolerance or action levels. Also the estimated daily intakes are well below than those recommended by WHO. This is a good indication about OCPs in the areas investigated but some further considerations on fish safety must be taken into account. An example on how fishes may act as bioindicators is reported. PMID:24184045

  11. Influence of the nature and age of cover crop residues on the sorption of three pesticides

    NASA Astrophysics Data System (ADS)

    Cassigneul, Ana; Alletto, Lionel; Chuette, Delphine; Le Gac, Anne-Laure; Hatier, Jules; Etievant, Veronique; Bergheaud, Valérie; Baumberger, Stéphanie; Méchin, Valérie; Justes, Eric; Benoit, Pierre

    2013-04-01

    In agricultural fields, soil and water quality preservation is strongly influenced by pesticides use and behavior. To limit the environmental impacts of agricultural activities, best management practices such as the use of cover crops are encouraged. Cover crops during the fallow period were found to be efficient in reducing nitrate leaching, controlling soil erosion, improving soil organic content and enhancing soil biological activity. This technique was also found to modify soil water dynamics in the following crop. According to these effects, modifications on pesticide behavior in soil, such as sorption, degradation and transport, are expected (Alletto et al., 2012 ; 2013). In this study, the impact of the nature and level of decomposition of cover crop was studied on the sorption characteristics of three pesticides. These pesticides differed in their physicochemical characteristics (hydrophobicity, solubility, persistence) and were two herbicides, S-metolachlor and glyphosate, which are largely used in maize production and predominantly found as pollutants in water; and one fungicide, epoxiconazole. Correlations between pesticide sorption and physicochemical characteristics of the cover crop residues were studied. Residues of oat, turnip rape, red clover and phacelia were collected in March 2011 and incubated at 28°C and at the water holding capacity during 0, 6, 28 or 56 days. For each date, adsorption of the three radiolabeled pesticides was measured in batch on the different cover crop residues, and their biochemical composition (Van Soest fractionation), hydrophobicity (contact angle measurement) and C/N ratio were determined. Results showed that the adsorption of the pesticides differed significantly according to (i) the pesticide, (ii) the nature of cover crop, (iii) the decomposition level of the cover crop and the interaction cover crop x decomposition time. Epoxiconazole was the most adsorbed molecule, with Kd values ranging from 161 ± 30 L/Kg (oat

  12. Removal of 16 pesticide residues from strawberries by washing with tap and ozone water, ultrasonic cleaning and boiling.

    PubMed

    Lozowicka, Bozena; Jankowska, Magdalena; Hrynko, Izabela; Kaczynski, Piotr

    2016-01-01

    The effects of washing with tap and ozone water, ultrasonic cleaning and boiling on 16 pesticide (ten fungicides and six insecticides) residue levels in raw strawberries were investigated at different processing times (1, 2 and 5 min). An analysis of these pesticides was conducted using gas chromatography with nitrogen-phosphorous and electron capture detection (GC-NPD/ECD). The processing factor (PF) for each pesticide in each processing technique was determined. Washing with ozonated water was demonstrated to be more effective (reduction from 36.1 to 75.1 %) than washing with tap water (reduction from 19.8 to 68.1 %). Boiling decreased the residues of the most compounds, with reductions ranging from 42.8 to 92.9 %. Ultrasonic cleaning lowered residues for all analysed pesticides with removal of up to 91.2 %. The data indicated that ultrasonic cleaning and boiling were the most effective treatments for the reduction of 16 pesticide residues in raw strawberries, resulting in a lower health risk exposure. Calculated PFs for alpha-cypermethrin were used to perform an acute risk assessment of dietary exposure. To investigate the relationship between the levels of 16 pesticides in strawberry samples and their physicochemical properties, a principal component analysis (PCA) was performed. Graphical abstract ᅟ. PMID:26694708

  13. Investigation into the validity of extrapolation in setting maximum residue levels for pesticides in crops of similar morphology.

    PubMed

    Reynolds, S L; Fussell, R J; MacArthur, R

    2005-01-01

    Field trials were initiated to investigate if extrapolation procedures, which were adopted to limit costs of pesticide registration for minor crops, are valid. Three pairs of crops of similar morphology; carrots/swedes, cauliflower/calabrese (broccoli) and French beans/edible-podded peas; were grown in parallel at four different geographical locations within the UK. The crops were treated with both systemic and non-systemic pesticides under maximum registered use conditions, i.e. the maximum permitted application rates and the minimum harvest intervals. Once mature, the crops were harvested and analysed for residues of the applied pesticides. The limits of quantification were in the range 0.005-0.02 mg kg(-1). Analysis of variance and bootstrap estimates showed that in general, the mean residue concentrations for the individual pesticides were significantly different between crop pairs grown on each site. Similarly, the mean residue concentrations of most of the pesticides in each crop across sites were significantly different. These findings demonstrate that the extrapolations of residue levels for most of the selected pesticide/crop combinations investigated; chlorfenvinphos and iprodione from carrots to swedes; carbendazim, chlorpyrifos, diflubenzuron and dimethoate from cauliflower to calabrese; and malathion, metalaxyl and pirimicarb from French beans to edible-podded peas; appear invalid. PMID:15895609

  14. Pesticide residues in human breast milk: risk assessment for infants from Punjab, India.

    PubMed

    Bedi, J S; Gill, J P S; Aulakh, R S; Kaur, P; Sharma, A; Pooni, P A

    2013-10-01

    Punjab state in India is an agrarian society, where agriculture is the lifeline of farming community. To keep pace with increasing demands of food for growing population the indiscriminate use of pesticides has led to the contamination of environment and food commodities in this region. Analysis of human breast milk samples (n=53) for pesticide residues revealed the presence of β-, γ-HCH, p,p' DDD, p,p' DDE, p,p' DDT and endrin with mean concentration of 97.9, 101.7, 239.8, 1574.1, 100.3 and 90.7 ng g(-1) lipid wt., respectively. In addition, occurrence of β-endosulfan, endosulfan sulphate, cypermethrin and chlorpyrifos in this study have also been reported for the first time in human breast milk in Punjab, India. With increase in parity, HCH and DDT residue burden in donor's milk decreased. Although levels of HCH and DDT residues in breast milk samples have decreased significantly, yet estimated daily intake values for DDT are higher than the FAO/WHO permissible tolerable daily intake values for few infants. PMID:23850662

  15. [Validation of ELISA Kits for Pesticide Residue Analysis in Vegetables and Fruits].

    PubMed

    Yamasaki, Tomomi; Inoue, Tomomi; Hirakawa, Yuki; Miyake, Shiro; Ueno, Eiji; Saito, Isao

    2015-01-01

    Five kinds of commercially available ELISA kits (acetamiprid, azoxystrobin, chlorothalonil, fenitrothion and imidacloprid) were validated for determination of pesticide residues in vegetables and fruits. The reaction characteristics were also examined to evaluate their influence on the determinations. The trueness value was 91-162%, the repeatability was 2.1-16.2%, and the reproducibility was 4.0-20.3%. The desired values were achieved for 18 among 30 combinations (60%) of the ELISA kits and the agricultural products examined. A standard curve was necessary for each of the ELISA examinations. The matrix of the agricultural products and pipetting skill of the lab technician both influenced the measurment results. PMID:26699271

  16. Reduction of hazardous organic solvent in sample preparation for hydrophilic pesticide residues in agricultural products with conventional liquid chromatography.

    PubMed

    Watanabe, Eiki; Kobara, Yuso; Baba, Koji; Eun, Heesoo

    2013-05-22

    An original extraction method using water as an extractant has been established for environmentally friendly sample preparation procedures for hydrophilic pesticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, methomyl, pymetrozine, thiacloprid, and thiamethoxam) in agricultural samples with conventional HPLC. Water-based extraction and cleanup with two solid-phase extraction cartridges can recover target hydrophilic pesticides quantitatively. The matrix effects of tested samples on the proposed method developed herein were negligibly small. Under the optimized conditions, the recoveries of almost all tested pesticides were 70-120% with satisfactory precision (%CV < 20%). The analytical data are in good accordance with Japanese or European Union guidelines for pesticide residue analysis. The reduction rate of hazardous organic solvents used for the proposed method and by reducing the sample size for extraction was about 70% compared with the Japanese authorized reference method used in this work. The results demonstrate the feasibility of the proposed sample preparation procedures for hydrophilic pesticides. PMID:23614723

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

    PubMed

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

    2015-04-01

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

  18. Pesticide residues in fruit samples: comparison of different QuEChERS methods using liquid chromatography-tandem mass spectrometry.

    PubMed

    Christia, C; Bizani, E; Christophoridis, C; Fytianos, K

    2015-09-01

    Acetate- and citrate-buffered quick, easy, cheap, effective, rugged, safe (QuEChERS) pretreatment methods were evaluated for the determination of various pesticides in peaches, grapes, apples, bananas, pears, and strawberries from various regions of Greece, using LC-MS/MS. The purposes of this study were (i) to evaluate which type of QuEChERS method was the most appropriate and effective for each matrix; (ii) to apply the selected QuEChERS method for each matrix, in order to detect and quantify pesticide residues in various fruit samples using UPLC-MS/MS; (iii) to examine the concentration distribution of pesticide classes among fruit originating from various areas; and (iv) to assess pesticide concentration distribution between peel and flesh of fruit in order to evaluate the penetration of pesticide residues in the fruit flesh. Acetate-buffered QuEChERS was found to be the most suitable technique for most of the fruit matrices. According to the recovery values at two different concentration levels, peaches should preferably be treated by the citrate-buffered type, whereas grapes, bananas, apples, pears, and strawberries are best treated by the acetate-buffered version, although the differences in efficiency were small. The addition of graphitized carbon black significantly decreases the recovery of specific pesticides in all matrices except for strawberries. The majority of values do not exceed the official maximum residue levels set by the European Commission. Organophosphates proved to be the most commonly detected category along with triazines-triazoles-conazoles group and by carbamates. Apples and pears seem to be the most contaminated fruit matrices among those tested. Distribution of pesticide classes shows variations between different regions, suggesting different pesticide application practices. In the case of peaches and pears, there is an equal distribution of detected pesticides between peel and flesh, indicating penetration of contaminants into the

  19. Assessment of Pesticide Residues in Flesh of Catla catla from Ravi River, Pakistan

    PubMed Central

    Akhtar, Mobeen; Mahboob, Shahid; Sultana, Salma; Sultana, Tayyaba; Alghanim, Khalid Abdullah; Ahmed, Zubair

    2014-01-01

    The levels of dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), endosulfan, endosulfan sulfate, carbofuran, and cartap which were estimated in the flesh of Catla catla sampled from ten sites of Ravi River between its stretches from Shahdara to Head Balloki were studied to know the level of contamination of the selected pesticides by GC-ECD method. All fish samples were found contaminated with different concentrations of DDT, DDE, endosulfan, and carbofuran; however, DDT and DDE concentrations were more than the maximum residue limits (MRLs) about food standards, while endosulfan sulfate and cartap were not detected. Pesticide concentrations in the fish flesh were ranged from 3.240 to 3.389 for DDT, 2.290 to 2.460 for DDE, 0.112 to 0.136 for endosulfan, and 0.260 to 0.370 μg g−1 for carbofuran. The findings revealed that the pesticide concentrations in the fish flesh decreased in the order: DDT > DDE > carbofuran > endosulfan. After Degh fall and After Hudiara nulla fall river sampling sites were found severely contaminated. It is proposed that a constant monitoring programs are needed to be initiated to overcome the present alarming situation. PMID:25003148

  20. Analysis of Bioenergy Residues (biochar and digestate) to Study the Fate of Pesticides for Biopurification Systems

    NASA Astrophysics Data System (ADS)

    Mukherjee, S.

    2015-12-01

    To overcome the problem of on farm point sources of pollution, environmental friendly and low cost technology filter systems are under development. Processes like sorption-desorption, dissipation behavior of three radiolabeled pesticides (Bentazone, Boscalid and Pyrimethanil) has been investigated at lab scale. Biochar and digestate mixtures with two types of soil (sandy and silt loam) had been used as a biofilter test material for a respiration study (over three month's time period) instead of conventional soil, peat and straw mixtures. The results show that digestate is an easily available C-source leading to highest release of CO2-C. It was found that with the addition of even a small amount (1 % W/W) of biochar there is a profound suppression in the CO2-C release.The driving mechanism for this suppression can be manifold like negative priming, chemisorption of CO2-C on biochar or combinations of all. Further, the fate of applied organic contaminants to biomixtures depends on factors like soil properties as well as biological degradation by soil microbes. To analyze the degradation potential of the different soil/amendment mixtures on pesticides a degradation study was performed. The results from the 14C labelled pesticides study indicated that a mixture of digestate (5%) and biochar (5%) well balanced the mineralization (~20% for bentazone, ~6% for boscalid and ~2% for pyrimethanil) and sorption process (>85% non-extractable residues for all pesticides) resulting in favorable dissipation process. To investigate the sorption-desorption potential of the above pesticides a batch equilibrium study was carried out with selected biomixtures. A higher Kd (>1500 L kg-1), kf (>400 μM1-1/nf L1/nfkg-1) and KL (>40 L kg-1) was obtained for all pesticides for the soil/digestate/biochar mixtures, which had a higher organic matter content. SUVA254 values justified the aromatic character of digestate (5%) and biochar (5%) mixture which showed highest Koc values among all

  1. Occurrence of organochlorine pesticide residues in eggs, chicken and meat in Jordan.

    PubMed

    Ahmad, Rafat; Salem, Nida' M; Estaitieh, Hussein

    2010-02-01

    Organochlorine pesticide (OCP) residues in 519 samples; comprising eggs, chicken and meat (lamb and beef), collected from Jordan were determined. All samples were analyzed for their residual contents of aldrin, dichlorodiphenyltrichloroethane and metabolites (DDTs), dieldrin, endosulfan isomers, endrin, hexachlorocyclohexane isomers (HCHs), heptachlor, heptachlor epoxide and hexachlorobenzene (HCB). The samples were Soxhlet extracted for 8h in 250mL petroleum ether. The cleanup of the samples was performed by Florisil column chromatography and analysis was done on a gas chromatography equipped with an electron capture detector (GC-ECD). The results indicated that 28% (38/134), 20% (23/115) and 49% (131/270) of the examined eggs, chicken and meat samples, respectively, were contaminated with OCP residues. HCHs and DDTs are the most prominently noticed compounds, as they were detected at a high incidence. On the other hand, heptachlor, heptachlor epoxide, HCB, aldrin and endrin compounds were only present in less than 7% of the analyzed samples. These residues are present despite complete ban on the use of OCPs for agricultural purposes in Jordan. No residues of op'-DDD, op'-DDT, dieldrin, alpha-endosulfan and beta-endosulfan were detected. PMID:20042222

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

    PubMed

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

    2016-05-01

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

  3. Pesticide residues in vineyard soils from Spain: Spatial and temporal distributions.

    PubMed

    Pose-Juan, Eva; Sánchez-Martín, María J; Andrades, M Soledad; Rodríguez-Cruz, M Sonia; Herrero-Hernández, Eliseo

    2015-05-01

    Spatial and temporal evaluations of seventeen pesticides and some of their degradation products were carried out in seventeen vineyard soils from La Rioja region (Spain). The soils were sampled in March, June and October 2012, and the pesticides were selected among those previously detected in surface and ground waters from the same area. All pesticides were detected in some of the soils in the three different areas of La Rioja at the different sampling times, with only the metalaxyl metabolite, CGA-62826, not being detected in any of the soils sampled in October. The highest concentrations were determined for the fungicides metalaxyl (11.5 μg kg(-1)) and triadimenol (26.1 μg kg(-1)), the herbicides fluometuron (174.6 μg kg(-1)) and terbuthylazine (403.3 μg kg(-1)), and the insecticide methoxyfenozide (4.61 μg kg(-1)). While the highest total concentration of pesticides was detected in March, the highest number of positive detections was recorded in June (46), as opposed to 26 and 19 in March and October, respectively. Significant differences were detected in the concentrations of herbicides in soils from the three areas in La Rioja, but this was not the case for the fungicides and the insecticides. The study revealed a more intensive use of herbicides in March, while the use of insecticides and fungicides probably depended on the specific needs of crops and/or the onset of diseases. The results are consistent with the residues found in waters in the region, and highlight the need to implement strategies for more efficient application of these compounds to avoid risk of water contamination. PMID:25679815

  4. Pesticide residues in eggs of wild birds: Adjustment for loss of moisture and lipid

    USGS Publications Warehouse

    Stickel, L.F.; Wiemeyer, Stanley N.; Blus, L.J.

    1973-01-01

    Eggs of wild birds collected for the purpose of measuring concentrations of pesticides or other pollutants vary from nearly fresh to nearly dry so that objective comparisons cannot be made on the basis of weight of the contents at the time of collection. Residue concentrations in the nearly dry eggs can be greatly exaggerated by this artifact. Valid interpretation of residue data depends upon compensation for these losses. A method is presented for making adjustments on the basis of volume of the egg, and formulas are derived for estimating the volume of eggs of eagles, ospreys, and pelicans from egg measurements. The possibility of adjustments on the basis of percentage of moisture, solids, or fat in fresh eggs is discussed also.

  5. Organochlorine pesticide residues in moths from the Baltimore, MD-Washington, DC area

    USGS Publications Warehouse

    Beyer, W.N.; Kaiser, T.E.

    1984-01-01

    Moths were collected with a light trap from 15 sites in the Baltimore, Maryland - Washington, D.C. area and analyzed for organochlorine pesticide residues. On the average, the species sampled contained 0.33 ppm heptachlor-chlordane compounds, 0.25 ppm DDE, and 0.11 ppm dieldrin. There were large differences in the concentrations detected in different species. Concentrations were especially high in moths whose larvae were cutworms, and were virtually absent from moths whose larvae fed on tree leaves. It was concluded that at least some species sampled could be an important source of insecticides to insectivorous wildlife. In some instances moths may be useful indicators of environmental contamination, especially when insectivorous wildlife species cannot be collected. However, the differences in residues observed among species means that only similar species should be compared, and this limits their potential for monitoring.

  6. Validation of QuEChERS method for the determination of 36 pesticide residues in fruits and vegetables from Ghana, using gas chromatography with electron capture and pulsed flame photometric detectors.

    PubMed

    Donkor, Augustine; Osei-Fosu, Paul; Nyarko, Stephen; Kingsford-Adaboh, Robert; Dubey, Brajesh; Asante, Isaac

    2015-01-01

    In this study, "Quick, Easy, Cheap, Effective, Rugged and Safe" 'QuEChERS' method was modified for the determination of 36 pesticides fortified at (0.01-1.0) mg kg(-1) in three vegetables and a fruit (lettuce, carrot, tomatoes and pineapples respectively) from Ghana. The method involved extraction with acetonitrile, phase separation with primary secondary amine and magnesium sulfate; the final injection solution was reconstituted in ethyl acetate. Organochlorine and synthetic pyrethroids residues were detected with electron capture detector whereas organophosphorus, pulsed flame photometric detector was used. The recoveries at different concentration levels (0.01, 0.1 and 1.0 mg kg(-1)) were in the range of 83% and 93% with relative standard deviation ranging from 2% to 10% (n = 5) and the coefficient of determination (R(2)) was greater than 0.99 for all the 36 pesticides. The method was successfully tested on 120 real samples from Accra markets and this proved to be useful for monitoring purposes particularly in laboratories that have no gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. PMID:26065516

  7. Analysis of pesticide multi-residues in leafy vegetables by ultrasonic solvent extraction and liquid chromatography-tandem mass spectrometry.

    PubMed

    Pan, Jian; Xia, Xiao-Xiao; Liang, Juan

    2008-01-01

    Ultrasonic solvent extraction (USE) of pesticide multi-residues including monocrotophos, dimethoate, imidacloprid, carbendazim, carbaryl and simazine from leafy vegetables is presented. The extraction procedure was optimized with regard to the solvent type and amount, sonication time and number of extraction steps. The extract did not need clean-up before injected into liquid chromatography-tandem mass spectrometry (LC-MS-MS) which was employed together with electron microscope to verify the effect of USE method. The proposed procedure allows the extraction of six pesticide residues in a single step with 40 ml of ethyl acetate for 35 min sonication, providing recovery over 83% and LOQ less than 1.4 microg/kg. The optimized USE method is a simple, low cost and an effective preparation method for determination of pesticide multi-residues at trace levels in leafy vegetables in comparison with homogenized extraction method. PMID:17664080

  8. Contribution of Sample Processing to Variability and Accuracy of the Results of Pesticide Residue Analysis in Plant Commodities.

    PubMed

    Ambrus, Árpád; Buczkó, Judit; Hamow, Kamirán Á; Juhász, Viktor; Solymosné Majzik, Etelka; Szemánné Dobrik, Henriett; Szitás, Róbert

    2016-08-10

    Significant reduction of concentration of some pesticide residues and substantial increase of the uncertainty of the results derived from the homogenization of sample materials have been reported in scientific papers long ago. Nevertheless, performance of methods is frequently evaluated on the basis of only recovery tests, which exclude sample processing. We studied the effect of sample processing on accuracy and uncertainty of the measured residue values with lettuce, tomato, and maize grain samples applying mixtures of selected pesticides. The results indicate that the method is simple and robust and applicable in any pesticide residue laboratory. The analytes remaining in the final extract are influenced by their physical-chemical properties, the nature of the sample material, the temperature of comminution of sample, and the mass of test portion extracted. Consequently, validation protocols should include testing the effect of sample processing, and the performance of the complete method should be regularly checked within internal quality control. PMID:26755282

  9. Flexible and Adhesive Surface Enhance Raman Scattering Active Tape for Rapid Detection of Pesticide Residues in Fruits and Vegetables.

    PubMed

    Chen, Jiaming; Huang, Youju; Kannan, Palanisamy; Zhang, Lei; Lin, Zhenyu; Zhang, Jiawei; Chen, Tao; Guo, Longhua

    2016-02-16

    The efficient extraction of targets from complex surfaces is vital for technological applications ranging from environmental pollutant monitoring to analysis of explosive traces and pesticide residues. In our present study, we proposed a proof-of-concept surface enhance Raman scattering (SERS) active substrate serving directly to the rapid extraction and detection of target molecules. The novel substrate was constructed by decorating the commercial tape with colloidal gold nanoparticles (Au NPs), which simultaneously provides SERS activity and "sticky" of adhesive. The utility of SERS tape was demonstrated by directly extracting pesticide residues in fruits and vegetables via a simple and viable "paste and peel off" approach. The obtained strong and easily distinguishable SERS signals allow us to detect various pesticide residues such as parathion-methyl, thiram, and chlorpyrifos in the real samples with complex surfaces including green vegetable, cucumber, orange, and apple. PMID:26810698

  10. Pesticide residues in river Yamuna and its canals in Haryana and Delhi, India.

    PubMed

    Kaushik, C P; Sharma, H R; Jain, S; Dawra, J; Kaushik, A

    2008-09-01

    Yamuna, a prominent river of India covers an extensive area of 345,843 km(2) from Yamunotri glacier through six Indian states. Residues of organochlorine pesticides (OCPs) namely, isomers of HCH and endosulfan, DDT and its metabolites, aldrin, dieldrin, were analysed in water of river Yamuna along its 346 km stretch passing through Haryana-Delhi-Haryana and the canals originating from it. beta-HCH, p.p'-DDT, p.p'-DDE and p.p'-DDD had maximum traceability in test samples (95-100%) followed by gamma-HCH, alpha-HCH and o.p'-DDD (60-84%) and o.p'-DDT, delta-HCH and o.p'-DDE (7-30%) while aldrin, dieldrin, alpha and beta endosulfan remained below detection limits (BDL). The concentration of SigmaHCH and SigmaDDT at different sites of the river ranged between 12.76-593.49 ng/l (with a mean of 310.25 ng/l) and 66.17-722.94 ng/l (with a mean of 387.9 ng/l), respectively. In canals the values were found between 12.38-571.98 ng/l and 109.12-1572.22 ng/l for SigmaHCH and SigmaDDT, respectively. Water of Gurgaon canal and Western Yamuna canal contained maximum and minimum concentration, respectively both of SigmaHCH and SigmaDDT residues. Sources of these pesticides and suggested measures to check pesticide pollution of this major Indian river, keeping in view its vital link with life, are discussed in this paper. PMID:18044005

  11. Pesticide adsorptivity of aged particulate matter arising from crop residue burns.

    PubMed

    Yang, Yaning; Sheng, Guangyao

    2003-08-13

    Particulates (ashes) arising from the burning of crop residues are potentially effective adsorbents for pesticides in agricultural soils. To determine the long-term adsorptive sustainability of ashes, a wheat (Triticum aestivum L.) ash was aged under environmentally relevant conditions (in CaCl(2) solution at room temperature and pH 7) in soil extract for 1 month and in a soil (1% ash) for a period of up to 12 months. The aged ash and ash-amended soil were used to sorb diuron from water. The diuron sorption was also measured in the presence of atrazine as a competing pesticide. There was no observed microbial impact on the stability of the wheat ash in soil. All isotherms with the ash were nonlinear type-I curves, suggestive of the surface adsorption. On a unit mass basis, the ash in soil extract was 600-10000 times more effective than the soil in sorbing diuron. Adsorption of dissolved soil organic matter (DOM) during aging on the ash surfaces reduced the diuron adsorption by 50-60%. Surface competition from the atrazine adsorption also reduced the ash adsorption of diuron by 10-30%. A total of 55-67% reduction in diuron sorption by the ash-amended soil was observed. Due to its high initial adsorptivity, the ash fraction of the aged ash-amended soil contributed >50% to the total diuron sorption. Thus, the wheat ash aged in the soil remained highly effective in adsorbing diuron. As crop residues are frequently burned in the field, pesticides in agricultural soils may be highly immobilized due to the presence of ashes. PMID:12903968

  12. Highly sensitive terahertz spectroscopy of residual pesticide using nano-antenna

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Kyu; Kim, Giyoung; Son, Joo-Hiuk; Seo, Minah

    2016-02-01

    In this report, a novel type of highly sensitive small molecule sensing tool has been employed to detect residual pesticide molecules including e. g. methomyl using terahertz (THz) time-domain spectroscopy (TDS) system with nano-slotantenna array. Enhance THz wave by the nano-slot-antenna array induces strong THz field enhancement around nano antenna and thus increases an absorption cross section leading to the detection sensitivity upto ppm level even in solution state. Measured spectrums in transmission and reflection show an excellent performance in both sensitivity and selectivity. We also tested the performance of our nano-antenna array in reflection imaging geometry to simply detect the contained residual pesticide at the real fruit surface as it is, without any extraction or sampling preprocess. The clear difference in the obtained THz reflection image distinguishes the stained area with methomyl from the bare area. Our observation can offer the possibility for further application as a prompt and an accurate small molecule monitoring tool in real time. A quantitative analysis tool for such small molecule can be also developed by this method.

  13. Simultaneous determination of pyrethroids from pesticide residues in porcine muscle and pasteurized milk using GC.

    PubMed

    Khay, Sathya; Abd El-Aty, A M; Choi, Jeong-Heui; Shin, Eun-Ho; Shin, Ho-Chul; Kim, Jin-Suk; Chang, Byung-Joon; Lee, Chi-Ho; Shin, Sung-Chul; Jeong, Ji Yoon; Shim, Jae-Han

    2009-01-01

    The principal goal of this work was to develop an efficient method for the simultaneous determination of four pyrethroid (PYR) insecticides, cyfluthrin, cyhalothrin, cypermethrin, and deltamethrin, in porcine muscle and pasteurized milk using liquid-liquid extraction (LLE). Sample extraction was carried out with and without additional column cleanup procedures, and the final determination was made using GC with electron-capture detector (ECD). The pesticide identity was confirmed using GC-MS in the SIM mode. Since there were minor differences between the extraction procedures, extraction without the additional cleanup procedure was used throughout the work. The method was validated by fortifying blank samples with half, two, and four times the maximum residue limit (MRL) of each PYR. The average recoveries (n = 6) ranged from 83.5 to 99.2% and 82.9 to 109% in porcine muscle and pasteurized milk, respectively. The repeatability of measurements expressed as RSDs, was in the range of 1.7-11.9 and 1.5-10.3% in porcine muscle and pasteurized milk, respectively. The LODs ranged from 3.3 to 9 and 3 to 8.1 ppm, whereas the LOQs ranged from 10 to 27.4 and 9 to 24.6 ppm, in porcine muscle and pasteurized milk, respectively. The applicability of the method was demonstrated by analyzing real samples collected from major cities in the Republic of Korea. No residues of the selected pesticides were detected in any of the samples. PMID:19107766

  14. 75 FR 11171 - Notice of Filing of Several Pesticide Petitions for Residues of Pesticide Chemicals in or on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... limited to: Crop production (NAICS code 111). Animal production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code 32532). This listing is not intended to...

  15. Occurrence and distribution study of residues from pesticides applied under controlled conditions in the field during rice processing.

    PubMed

    Pareja, Lucía; Colazzo, Marcos; Pérez-Parada, Andrés; Besil, Natalia; Heinzen, Horacio; Böcking, Bernardo; Cesio, Verónica; Fernández-Alba, Amadeo R

    2012-05-01

    The results of an experiment to study the occurrence and distribution of pesticide residues during rice cropping and processing are reported. Four herbicides, nine fungicides, and two insecticides (azoxystrobin, byspiribac-sodium, carbendazim, clomazone, difenoconazole, epoxiconazole, isoprothiolane, kresoxim-methyl, propanil, quinclorac, tebuconazole, thiamethoxam, tricyclazole, trifloxystrobin, λ-cyhalotrin) were applied to an isolated rice-crop plot under controlled conditions, during the 2009-2010 cropping season in Uruguay. Paddy rice was harvested and industrially processed to brown rice, white rice, and rice bran, which were analyzed for pesticide residues using the original QuEChERS methodology and its citrate variation by LC-MS/MS and GC-MS. The distribution of pesticide residues was uneven among the different matrices. Ten different pesticide residues were found in paddy rice, seven in brown rice, and eight in rice bran. The highest concentrations were detected in paddy rice. These results provide information regarding the fate of pesticides in the rice food chain and its safety for consumers. PMID:22497619

  16. Overview of pesticide residues in stored pollen and their potential effect on bee colony (Apis mellifera) losses in Spain.

    PubMed

    Bernal, J; Garrido-Bailón, E; Del Nozal, M J; González-Porto, A V; Martín-Hernández, R; Diego, J C; Jiménez, J J; Bernal, J L; Higes, M

    2010-12-01

    In the last decade, an increase in honey bee (Apis mellifera L.) colony losses has been reported in several countries. The causes of this decline are still not clear. This study was set out to evaluate the pesticide residues in stored pollen from honey bee colonies and their possible impact on honey bee losses in Spain. In total, 1,021 professional apiaries were randomly selected. All pollen samples were subjected to multiresidue analysis by gas chromatography-mass spectrometry (MS) and liquid chromatography-MS; moreover, specific methods were applied for neonicotinoids and fipronil. A palynological analysis also was carried out to confirm the type of foraging crop. Pesticide residues were detected in 42% of samples collected in spring, and only in 31% of samples collected in autumn. Fluvalinate and chlorfenvinphos were the most frequently detected pesticides in the analyzed samples. Fipronil was detected in 3.7% of all the spring samples but never in autumn samples, and neonicotinoid residues were not detected. More than 47.8% of stored pollen samples belonged to wild vegetation, and sunflower (Heliantus spp.) pollen was only detected in 10.4% of the samples. A direct relation between pesticide residues found in stored pollen samples and colony losses was not evident accordingly to the obtained results. Further studies are necessary to determine the possible role of the most frequent and abundant pesticides (such as acaricides) and the synergism among them and with other pathogens more prevalent in Spain. PMID:21309214

  17. Pesticides in persimmons, jujubes and soil from China: Residue levels, risk assessment and relationship between fruits and soils.

    PubMed

    Liu, Yihua; Li, Shiliang; Ni, Zhanglin; Qu, Minghua; Zhong, Donglian; Ye, Caifen; Tang, Fubin

    2016-01-15

    Extreme and uncontrolled usage of pesticides produces a number of problems for vegetation and human health. In this study, the existence of organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and fungicides (FUs) were investigated in persimmons/jujubes and their planted soils, which were collected from China. One OP (dimethoate), three OCs (DDT, quintozene and aldrin), six PYs (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) and two FUs (triadimefon and buprofezin) were found in 36.4% of persimmons and 70.8% of jujubes, with concentrations from 1.0 μg/kg to 2945.0 μg/kg. The most frequently detected pesticides in the two fruits were fenpropathrin in persimmons and cypermethrin in jujubes, with the detection frequencies of 30.0% and 22.7%, respectively. The residues of 4.5% (persimmon) and 25.0% (jujube) of samples were higher than the maximum residue limits (MRLs) of China. Compared with the fruits, more types of pesticides and higher residues were observed in their planted soils. The most frequently detected pesticides were HCH in persimmon soil and DDT in jujube soil, with the detection frequencies of 10.9% and 12.7%, respectively. For the tested samples, 39.1% of fruit samples and 63.0% of soil samples with multiple residues (containing more than two pesticides) were noted, even up to 8 residues in fruits and 14 residues in soils. Except for cyhalothrin, the other short-term risks for the tested pesticides in the fruits were below 10%, and the highest long-term risk was 14.13% for aldrin and dieldrin. There was no significant health risk for consumers via consumption of the two fruits. PMID:26544891

  18. Comprehensive multi-residue method for the target analysis of pesticides in crops using liquid chromatography-tandem mass spectrometry.

    PubMed

    Hiemstra, Maurice; de Kok, André

    2007-06-22

    A liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) multi-residue method for the simultaneous target analysis of a wide range of pesticides and metabolites in fruit, vegetables and cereals has been developed. Gradient elution has been used in conjunction with positive mode electrospray ionization tandem mass spectrometry to detect up to 171 pesticides and/or metabolites in different crop matrices using a single chromatographic run. Pesticide residues were extracted/partitioned from the samples with acetone/dichloromethane/light petroleum. The analytical performance was demonstrated by the analysis of extracts from lettuce, orange, apple, cabbage, grape and wheat flour, spiked at three concentration levels ranging from 0.01 to 0.10 mg/kg for each pesticide and/or metabolite. In general, recoveries ranging from 70 to 110%, with relative standard deviations better than 15%, were obtained. The recovery and repeatability data are in good accordance with EU guidelines for pesticide residue analysis. The limit of quantification for all targeted pesticides and metabolites tested was 0.01 mg/kg. The selectivity and robustness of the LC-MS/MS method was demonstrated by a 1-year comparison of its analytical results with those obtained from our validated GC and LC multi-residue methods applied to more than 3500 routine samples. The validated LC-MS/MS method has been implemented in our analytical scheme since 2004, replacing four of the conventional detection methods, i.e. GC-flame-photometric detection (acephate, methamidophos, etc.), GC-nitrogen-phosphorus detection, LC-UV detection (carbendazim, thiabendazole, imazalil and prochloraz) and LC-fluorescence detection (N-methylcarbamate pesticides). During a 3-year period, the LC-MS/MS method has been applied to the analyses of more than 12,000 samples. PMID:17442324

  19. 75 FR 60452 - Notice of Filing of Several Pesticide Petitions for Residues of Pesticide Chemicals in or on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... identification (ID) number and the pesticide petition number (PP) of interest as shown in the body of this... pesticide petition number of interest as shown in the body of this document. EPA's policy is that all... not know your identity or contact information unless you provide it in the body of your comment....

  20. 75 FR 28009 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    ... the use of special characters, any form of encryption, and be free of any defects or viruses. Docket..., papaya, star apple, black sapote, mango, sapodilla, canistel, and mamey sapote at 0.20 ppm; and tea at 15...) under 40 CFR 180.920 when used as a pesticide inert ingredient in pesticide formulations. A...