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Sample records for organophosphorus pesticide residues

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

    NASA Astrophysics Data System (ADS)

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

    2007-08-01

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

  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.

  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. Gas chromatography with flame photometric detection of 31 organophosphorus pesticide residues in Alpinia oxyphylla dried fruits.

    PubMed

    Zhao, Xiangsheng; Kong, Weijun; Wei, Jianhe; Yang, Meihua

    2014-11-01

    A simple, rapid and effective gas chromatography-flame photometric detection method was established for simultaneous multi-component determination of 31 organophosphorus pesticides (OPPs) residues in Alpinia oxyphylla, which is widely consumed as a traditional medicine and food in China. Sample preparation was completed in a single step without any clean-up procedure. All pesticides expressed good linear relationships between 0.004 and 1.0 μg/mL with correlation coefficients higher than 0.9973. The method gave satisfactory recoveries for most pesticides. The limits of detection varied from 1 to 10 ng/mL, and the limits of quantification (LOQs) were between 4 and 30 ng/mL. The proposed method was successfully applied to 55 commercial samples purchased from five different areas. Five pesticide residues were detected in four (7.27%) samples. The positive samples were confirmed by gas chromatography with tandem mass spectrometry (GC-MS/MS).

  5. 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.

  6. [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.

  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. 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.

  11. 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.

  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

    2016-01-01

    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.

  14. 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

  15. Analysis of six organophosphorus pesticide residues in apples and pears using cloud-point extraction coupled with HPLC-UV.

    PubMed

    Zhang, Lijin; Chen, Fang; Zhang, Wenhuan; Pan, Canping

    2014-01-01

    A cloud-point extraction (CPE) method with Triton X-114 has been developed for analysis of six organophosphorus pesticides (OPPs) in apples and pears. In this CPE procedure, the effects of the surfactant volume, mass of sodium chloride, equilibrium temperature, equilibrium time, and pH on the extraction procedure were investigated. Under the optimal CPE conditions, the analytes were enriched 20-fold and the LODs dropped to 0.44-5.20 microg/kg. Furthermore, the proposed extraction method was validated by the correlation coefficient (R2) of the calibration curve, repeatability (RSD, n = 6), and fortified recoveries, which were 0.9967-0.9993, 2.7-6.5, and 74.7-104.5%, respectively. Based on these results, it could be concluded that the proposed CPE method with Triton X-114 was suitable for the effective extraction and enrichment of OPP residues in the apple and pear samples.

  16. A method for the analysis of organophosphorus pesticide residues in Mexican axolotl.

    PubMed

    García de Llasera, Martha P; Cruz-Reyes, Leopoldo; Vera-Avila, Luz E

    2010-01-01

    A method based on matrix solid-phase dispersion (MSPD) was developed for quantitative extraction of three organophosphorus pesticides (OPPs) from the Mexican axolotl, Ambystoma mexicanum. The determination was carried out using high- performance liquid chromatography (HPLC) with diode array spectrophotometric UV detection (DAD). The MSPD extraction with octadecylsilyl (C18) sorbent combined with a silica gel clean-up and acetonitrile elution was optimised for chlorpyrifos, fenthion and methyl parathion. The method was validated, yielding recovery values higher than 90%. The precision, expressed as the relative standard deviation (RSD), was less than or equal to 6% in muscle samples at spiking levels of 10 and 5 ppm. Linearity was studied from 15 to 60 ppm for chlorpyrifos and fenthion, and from 7.5 to 30 ppm for methyl parathion. The limits of detection (LODs) were found to be less than or equal to 0.5 ppm. This method was applied to the analysis of samples from a chlorpyrifos-exposed axolotl, demonstrating its use as an analytical tool for toxicological studies. PMID:20390927

  17. Monitoring of organochlorine and organophosphorus pesticide residues in water during different seasons of Tighra reservoir Gwalior, Madhya Pradesh, India.

    PubMed

    Mamta; Rao, R J; Wani, Khursheed Ahmad

    2015-11-01

    Analysis of pesticides during different seasons for pesticidal contamination in water samples of Tighra reservoir was carried out on gas chromatograph-electron capture detector with capillary columns following multiresidual analytical technique. Organochlorine pesticides, viz., hexachlorobenzene (HCB), alpha-benzene hexachloride (BHC), beta-BHC, γ-BHC, heptachlor, aldrin, alpha-endosulfan, beta-endosulfan, p,p-DDE, dieldrin, o,p-dichlorodiphenyldichloroethane (DDD), p,p-DDD, p,p-dichlorodiphenyltrichloroethane (DDT), and endrin, and organophosphorus pesticides, viz., choloropyrifos, methyl parathion, diazion, dicholorovos, ethion, malathion, and parathion, were detected in water samples during different seasons. However, the pesticide concentration varied during different seasons at different sites. The prominent reason of contamination is the use of pesticides (both organochlorine and organophosphorus) in the agricultural fields near Tighra reservoir. On the basis of our observations, more extensive monitoring studies need to be carried out, covering all wetlands of Madhya Pradesh to enforce the policies for the restricted application of pesticides in agricultural fields adjacent to wetlands.

  18. 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

  19. [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

  20. 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.

  1. Selection of DNA aptamers that bind to four organophosphorus pesticides.

    PubMed

    Wang, Li; Liu, Xianjin; Zhang, Qiang; Zhang, Cunzheng; Liu, Yuan; Tu, Kang; Tu, Jian

    2012-05-01

    Single-stranded DNA (ssDNA) aptamers against four organophosphorus pesticides (phorate, profenofos, isocarbophos and omethoate) were simultaneously isolated from an immobilized random ssDNA library by systematic evolution of ligands by exponential enrichment (SELEX) technique. After 12 rounds of in vitro selection, five ssDNA aptamer candidates were selected and their binding affinities were identified by a novel method using a molecular beacon. Two of the five ssDNA sequences, SS2-55 and SS4-54, demonstrated higher affinities and specificities to the four organophosphorus pesticides. They were defined as broad-spectrum aptamers binding to four different targets and their simulated secondary structures showed highly distinct features with typical stem and loop structures. The dissociation constant of SS2-55 and SS4-54 binding to the four organophosphorus pesticides ranged from 0.8 to 2.5 μM. These aptamers offered application potential in the analysis and/or neutralization of the residues of the four organophosphorus pesticides.

  2. Selection of DNA aptamers that bind to four organophosphorus pesticides.

    PubMed

    Wang, Li; Liu, Xianjin; Zhang, Qiang; Zhang, Cunzheng; Liu, Yuan; Tu, Kang; Tu, Jian

    2012-05-01

    Single-stranded DNA (ssDNA) aptamers against four organophosphorus pesticides (phorate, profenofos, isocarbophos and omethoate) were simultaneously isolated from an immobilized random ssDNA library by systematic evolution of ligands by exponential enrichment (SELEX) technique. After 12 rounds of in vitro selection, five ssDNA aptamer candidates were selected and their binding affinities were identified by a novel method using a molecular beacon. Two of the five ssDNA sequences, SS2-55 and SS4-54, demonstrated higher affinities and specificities to the four organophosphorus pesticides. They were defined as broad-spectrum aptamers binding to four different targets and their simulated secondary structures showed highly distinct features with typical stem and loop structures. The dissociation constant of SS2-55 and SS4-54 binding to the four organophosphorus pesticides ranged from 0.8 to 2.5 μM. These aptamers offered application potential in the analysis and/or neutralization of the residues of the four organophosphorus pesticides. PMID:22261866

  3. 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)

  4. 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

  5. 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...

  6. 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

  7. Management of acute organophosphorus pesticide poisoning

    PubMed Central

    Eddleston, Michael; Buckley, Nick A; Eyer, Peter; Dawson, Andrew H

    2008-01-01

    Summary Organophosphorus pesticide self-poisoning is an important clinical problem in rural regions of the developing world, and kills an estimated 200 000 people every year. Unintentional poisoning kills far fewer people but is a problem in places where highly toxic organophosphorus pesticides are available. Medical management is difficult, with case fatality generally more than 15%. We describe the limited evidence that can guide therapy and the factors that should be considered when designing further clinical studies. 50 years after first use, we still do not know how the core treatments—atropine, oximes, and diazepam—should best be given. Important constraints in the collection of useful data have included the late recognition of great variability in activity and action of the individual pesticides, and the care needed cholinesterase assays for results to be comparable between studies. However, consensus suggests that early resuscitation with atropine, oxygen, respiratory support, and fluids is needed to improve oxygen delivery to tissues. The role of oximes is not completely clear; they might benefit only patients poisoned by specific pesticides or patients with moderate poisoning. Small studies suggest benefit from new treatments such as magnesium sulphate, but much larger trials are needed. Gastric lavage could have a role but should only be undertaken once the patient is stable. Randomised controlled trials are underway in rural Asia to assess the effectiveness of these therapies. However, some organophosphorus pesticides might prove very difficult to treat with current therapies, such that bans on particular pesticides could be the only method to substantially reduce the case fatality after poisoning. Improved medical management of organophosphorus poisoning should result in a reduction in worldwide deaths from suicide. PMID:17706760

  8. Determination of organophosphorus pesticide residues in vegetables by an enzyme inhibition method using α-naphthyl acetate esterase extracted from wheat flour*

    PubMed Central

    Wang, Jun-liang; Xia, Qing; Zhang, An-ping; Hu, Xiao-yan; Lin, Chun-mian

    2012-01-01

    The widespread use of organophosphorus pesticides (OPs) poses a great threat to human health and has made the detection of OP residues in food an important task, especially in view of the fact that easy and rapid detection methods are needed. Because OPs have inhibitory effects on the activity of α-naphthyl acetate esterase (ANAE) in plants, in this work we evaluated the possibility of detecting OPs in vegetables with ANAE extracted from commercial flour. The limits of detection (LODs) obtained for methamidophos, dichlorvos, phoxim, dimethoate, and malathion in lettuce samples with crude ANAE were 0.17, 0.11, 0.11, 0.96, and 1.70 mg/kg, respectively. Based on the maximum residue limits (MRLs) for OPs in food stipulated by Chinese laws which are 0.05, 0.20, 0.05, 1.00, and 8.00 mg/kg for methamidophos, dichlorvos, phoxim, dimethoate, and malathion, respectively, the esterase inhibition method with crude ANAE had sufficient sensitivity to detect the residues of dichlorvos, dimethoate, and malathion in lettuce, but it could not be used to guarantee the safety of the same samples if methamidophos or phoxim residue was present. The sensitivity of the method was improved by the use of esterase purified by ammonium sulfate salting-out. The LODs obtained for methamidophos and phoxim with purified esterase were lower than the MRLs for these OPs in food. This is a very promising method for the detection of OP residues in vegetables using crude or purified esterase because of its cheapness, sensitivity, and convenience. PMID:22467368

  9. 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.

  10. 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

  11. Compound specific isotope analysis of organophosphorus pesticides.

    PubMed

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

    2014-09-01

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

  12. 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

  13. 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...

  14. [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.

  15. [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

  16. 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.

  17. 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

  18. 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...

  19. Determination of organophosphorus pesticides and their major degradation product residues in food samples by HPLC-UV.

    PubMed

    Peng, Guilong; He, Qiang; Lu, Ying; Mmereki, Daniel; Zhong, Zhihui

    2016-10-01

    A simple method based on dispersive solid-phase extraction (DSPE) and dispersive liquid-liquid microextraction method based on solidification of floating organic droplets (DLLME-SFO) was developed for the extraction of chlorpyrifos (CP), chlorpyrifos-methyl (CPM), and their main degradation product 3,5,6-trichloro-2-pyridinol (TCP) in tomato and cucumber samples. The determination was carried out by high performance liquid chromatography with ultraviolet detection (HPLC-UV). In the DSPE-DLLME-SFO, the analytes were first extracted with acetone. The clean-up of the extract by DSPE was carried out by directly adding activated carbon sorbent into the extract solution, followed by shaking and filtration. Under the optimum conditions, the proposed method was sensitive and showed a good linearity within a range of 2-500 ng/g, with the correlation coefficients (r) varying from 0.9991 to 0.9996. The enrichment factors ranged from 127 to 138. The limit of detections (LODs) were in the range of 0.12-0.68 ng/g, and the relative standard deviations (RSDs) for 50 ng/g of each analytes in tomato samples were in the range of 3.25-6.26 % (n = 5). The proposed method was successfully applied for the extraction and determination of the mentioned analytes residues in tomato and cucumber samples, and satisfactory results were obtained. PMID:27378220

  20. 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

  1. Wildlife mortality attributed to organophosphorus and carbamate pesticides

    USGS Publications Warehouse

    Glaser, L.C.; LaRoe, E.T.; Farris, G.S.; Puckett, C.E.; Doran, P.D.; Mac, M.J.

    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.

  2. 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.

  3. 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....

  4. 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.

  5. 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%).

  6. 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

  7. Pesticide residues in eagles

    USGS Publications Warehouse

    Reichel, W.L.; Cromartie, E.; Lamont, T.G.; Mulhern, B.M.; Prouty, R.M.

    1969-01-01

    Bald and golden eagles found sick or dead in 18 States and Canada during 1964-1965 were analyzed for pesticide residues. Residues in bald eagles were considerably higher than in golden eagles. Residues of DDE, DDD, and dieldrin were detected in all samples of bald eagle carcasses; other compounds found, less frequently were heptachlor epoxide, endrin, and DCBP, a metabolite of DDT. DDE was detected in all samples of golden eagle carcasses; DDD, DDT, dieldrin, and heptachlor epoxide were detected less frequently.

  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.

  9. 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

  10. HPLC SEPARATION OF CHIRAL ORGANOPHOSPHORUS PESTICIDES ON POLYSACCHARIDE CHIRAL STATIONARY PHASES

    EPA Science Inventory

    High-performance liquid chromatographic separation of the individual enantiomers of 12 organophosphorus pesticides (OPs) were obtained on polysaccharide chiral HPLC columns using an alkane-alcohol mobile phase. The OP pesticides were crotoxyphos, dialifor, dyfonate, fenamiphos, ...

  11. HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION OF THE ENANTIOMERS OF ORGANOPHOSPHORUS PESTICIDES ON POLYSACCHARIDE CHIRAL STATIONARY PHASES

    EPA Science Inventory

    High-performance liquid chromatographic separation of the individual enantiomers of 12 organophosphorus pesticides (OPs) was obtained on polysaccharide enantioselective HPLC columns using alkane-alcohol mobile phase. The OP pesticides were crotoxyphos, dialifor, fonofos, fenamiph...

  12. 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

  13. 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.

  14. 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

  15. [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

  16. 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...

  17. 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

  18. 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

  19. Determination of carbamate and organophosphorus pesticides in vegetable samples and the efficiency of gamma-radiation in their removal.

    PubMed

    Chowdhury, Muhammed Alamgir Zaman; Jahan, Iffat; Karim, Nurul; Alam, Mohammad Khorshed; Abdur Rahman, Mohammad; 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.

  20. 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

  1. 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...

  2. 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...

  3. 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

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. Separation of organophosphorus pesticides by using nano-liquid chromatography.

    PubMed

    Buonasera, Katia; D'Orazio, Giovanni; Fanali, Salvatore; Dugo, Paola; Mondello, Luigi

    2009-05-01

    In the present research, the separation of a series of organophosphorus pesticides (fensulfothion, fenamiphos, profenofos, fonofos, isofenphos, dialifos, sulprofos and prothiofos), by using nano-liquid chromatography (nano-LC) with UV detection is described. Three 100 microm ID capillary columns, packed with different silica-based stationary phases (CN, C(18), and phenyl), were investigated. Among these, the phenyl column offered the best results in terms of chromatographic performance, and was selected for pesticide analyses. Parameters, such as sample dilution solvent, injection volume, mobile phase composition and flow rate, were optimized in order to define the ideal experimental conditions. With the aim of improving sensitivity, on-column focusing of large injection volumes was applied: a sensitivity increase of circa 100-fold was attained, with limits of detection (LODs) and quantification (LOQs) within the 4.4-37.5 and 14.5-125.0 ng/mL ranges, respectively. The method was validated, with satisfactory results, through the measurement of the following parameters: limits of detection and quantification, precision, linearity and recovery. Finally, five different baby foods, previously fortified with a solution of the eight aforementioned pesticides, and then subjected to liquid-liquid extraction and solid-phase extraction clean-up, were analyzed. PMID:19321170

  10. 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

  11. 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

  12. 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

  13. 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).

  14. 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

  15. 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

  16. 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...

  17. Development of an Enzyme Linked Immunosorbent Assay and an Immunochromatographic Assay for Detection of Organophosphorus Pesticides in Different Agricultural Products

    PubMed Central

    Hua, Xiude; Yang, Jifei; Wang, Limin; Fang, Qingkui; Zhang, Gaiping; Liu, Fengquan

    2012-01-01

    Objective Organophosphorus (OP) pesticides are considered hazardous substances because of their high toxicity to nontarget species and their persistence in the environment and agricultural products. Therefore, it is important to develop a rapid, sensitive, and economical method for detecting OP pesticides and their residues in food and the environment. Methods A broad, selective monoclonal antibody (MAb) for organophosphorus pesticides was produced. Based on the MAb, an enzyme linked immunosorbent assay (ELISA) and an immunochromatography assay (ICA) for detecting OP pesticides in different agricultural products were developed using a binding inhibition format on microtiter plates and a membrane strip, respectively. Results Under the optimized conditions, the IC50 values of the ELISA ranged from 3.7 to 162.2 ng mL–1 for the 8 OP pesticides. The matrix interferences of Apple, Chinese cabbage, and greengrocery were removed by 40-fold dilution, the recoveries from spiked samples ranged from 79.1% to 118.1%. The IC50 values of ICA for the 8 OP pesticides ranged from 11.8 to 470.4 ng mL−1. The matrix interference was removed from the Chinese cabbage and Apple samples with 5-fold dilution, and the interference was removed from the greengrocery samples with 20-fold dilution. The recoveries from the spiked samples ranged between 70.6 and 131.9%. The established ELISA and ICA were specific selectivity for the 8 OP pesticides. Conclusions The established ELISA is a sensitive screening method for the detection of OP pesticides, but the ELISA detection method depends on a laboratory platform and requires a relative long assay time and several steps operation. The established ICA is very useful as a screening method for the quantitative, semi-quantitative or qualitative detection of OP pesticides in agricultural products, and it has advantages over ELISA methods with regard to factors such as the testing procedure, testing time, and matrix interferences, among others. PMID

  18. 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

  19. Respiratory Failure in Acute Organophosphorus Pesticide Self-Poisoning

    PubMed Central

    Eddleston, Michael; Mohamed, Fahim; Davies, James OJ; Eyer, Peter; Worek, Franz; Sheriff, MH Rezvi; Buckley, Nick A

    2006-01-01

    Background: Acute organophosphorus (OP) pesticide poisoning is a major clinical problem in the developing world. Textbooks ascribe most deaths to respiratory failure occurring in one of two distinct clinical syndromes - acute cholinergic respiratory failure or the intermediate syndrome. The delayed failure appears to be due to respiratory muscle weakness, but its pathophysiology is not yet clear. Aim: To describe the clinical patterns of OP-induced respiratory failure and to determine whether the two syndromes are clinically distinct. Design: Prospective cohort study of 376 patients with confirmed OP poisoning. Methods: Patients were observed throughout their admission to three Sri Lankan hospitals. Exposure was confirmed by butyrylcholinesterase and blood OP assays. Results: Ninety of 376 patients (24%) required intubation, 52 (58%) within 2 hrs of admission while unconscious with cholinergic features. Twenty-nine (32%) were well on admission but then required intubation after 24 hrs while conscious and without cholinergic features. These two syndromes were not clinically distinct and had much overlap. In particular, some patients who required intubation on arrival subsequently recovered conscious but could not be extubated, requiring ventilation for up to 6 days. Discussion: Respiratory failure did not occur as two discrete clinical syndromes within distinct time frames. Instead, the pattern of failure was variable and overlapped in some patients. There seemed to be two underlying mechanisms - an early acute mixed central and peripheral respiratory failure, and a late peripheral respiratory failure - rather than two defined clinical syndromes. PMID:16861715

  20. 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
    ...

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Health risk assessment of pesticides residue in maize and cowpea from Ejura, Ghana.

    PubMed

    Akoto, O; Andoh, H; Darko, G; Eshun, K; Osei-Fosu, P

    2013-06-01

    Low productivity in agriculture due to damage cause by pests has led to the application of pesticides to control pest infestation. Residues of pesticides applied on crops are often found in the food which can cause chronic effect on the health of humans who consume such products. The aim of this study is to measure pesticides residues in maize and cowpea and compare the values with stablished safety limits. A total of 37 pesticides comprising 15 organochlorines, 13 organophosphorus and 9 pyrethroids pesticides were identified in maize and cowpea samples obtained from farms in Ejura. Analytical methods included solvent extraction of the pesticide residues and their subsequent quantification using gas chromatograph equipped with Electron Capture Detector and Pulse Flame Photometric Detector after clean-up on alumina/activated charcoal column. The results showed that the mean concentration of pesticides in maize ranged from 0.001 to 0.103 mg kg(-1) for organochlorine pesticides, 0.002-0.019 mg kg(-1) for organophosphorus pesticides and 0.002-0.028 mg kg(-1) for pyrethroids pesticides. In cowpea the mean concentration ranged from 0.001 to 0.108 mg kg(-1) for organochlorine pesticides, 0.002-0.015 mg kg(-1) for organophosphorus pesticides and 0.001-0.039 mg kg(-1) for pyrethroids pesticides. Maximum Residue Limits for β-HCH, β-endosulfan, p,p'-DDE and p,p'-DDD were exceeded in both maize and cowpea samples. Health risk estimation revealed that residues of heptachlor, dieldrin, endrin, β-endosulfna, γ-chlordane and chlorfenvinphos found in maize exceeded the Acceptable Daily Intake. Similarly the levels of heptachlor and p,p'-DDD found in cowpea also exceeded the Acceptable Daily Intake. This suggests a great potential for chronic toxicity to consumers of these food items.

  7. Pesticidal residues in animal tissues

    USGS Publications Warehouse

    DeWitt, J.B.; Menzie, C.M.; Adomaitis, V.A.; Reichel, W.L.

    1960-01-01

    Tests with penned starlings, rats, pheasants, and ducks indicated that each species differs in sensitivity to the various pesticides. Residues in tissues are proportional to the degree of exposure during area treatment and they are also found in animals shot six or more months after treatment. The presence of more than 20-30 ppm of DDT, 20 ppm of chlordan, and 6-20 ppm of heptachlor epoxide in quail tissues indicated that the birds had ingested lethal dosages of the pesticides.

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

    PubMed

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

    2014-05-30

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

  9. Evaluation of pressurized liquid extraction for determination of organophosphorus and pyrethroid pesticides in soybean.

    PubMed

    Yarita, Takashi; Aoyagi, Yoshie; Otake, Takamitsu

    2012-01-01

    The purpose of this study was to develop an analytical method for the determination of organophosphorus and pyrethroid pesticides in soybean by pressurized liquid extraction (PLE). Two organic solvents, acetone and acetonitrile, were evaluated as extraction solvents. In both cases, the amount of extract was enhanced with increasing extraction temperature. The extracts obtained using acetonitrile were measured by gas chromatography/mass spectrometry after a cleanup process based on the analytical method for the Japanese Positive List System for Agricultural Chemicals Remaining in Foods. The effect of extraction temperature (range: 40- 130°C) on extraction efficiency was evaluated by a recovery study using 21 organophosphorus pesticides and 10 pyrethroid pesticides as target analytes and acetonitrile as the solvent. The results indicated that at 130°C, some organophosphorus pesticides might be degraded, whereas extraction temperatures between 70°C and 100°C were optimal. Next, a prepared sample containing fenitrothion and permethrin was analyzed. Although the sample was not soaked in water prior to analysis, PLE provided analytical results comparable to those obtained by solvent extraction with homogenization. Therefore, PLE is considered a simple and alternative technique for the extraction of organophosphorus and pyrethroid pesticides in soybean.

  10. 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...

  11. 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...

  12. 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

  13. 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

  14. 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.

  15. Movement and deposition of two organophosphorus pesticides within a residence after interior and exterior applications.

    PubMed

    Lewis, R G; Fortune, C R; Blanchard, F T; Camann, D E

    2001-03-01

    Post-application temporal and spatial distributions of two organophosphorus pesticides, diazinon (O,O-diethyl O-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] phosphorothioate, CAS No. 333-41-5) and chlorpyrifos [O,O-diethyl-O-(2-isopropyl-6-methyl-4-pyrimidinyl) phosphorothioate, CAS No. 2921-88-2], were monitored after homeowner applications for indoor and outdoor insect control. Samples of indoor air, vacuumable carpet dust, carpet dislodgeable residues, deposits on bare floors, table tops and dinnerware, surrogate food, and residues on children's hands and toys were taken before and up to 12 days after treatments in the family room, kitchen, and child's bedroom. Results from the study demonstrate the nature and magnitude of translocation of pesticides from the areas of application to surfaces accessible for human contact and permit comparisons of potential exposures via respiration and dermal contact/oral ingestion. Potential indoor inhalation exposures were estimated to be as high as 0.5 microg/kg/day for diazinon applied indoors and 0.05 microg/kg/day for chlorpyrifos applied to the outside perimeter of the house. While ingestion of carpet dust at the rate of 100 microg/day would have added a maximum of only approximately 0.01 microg/kg/day to the daily dose, residues found on the children's hands suggest that repeated mouthing could have contributed as much as 1-1.5 microg/kg/day. These estimates are below the U.S. Environmental Protection Agency (EPA) reference dose for chlorpyrifos, but exceed those for diazinon. PMID:11266098

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

    PubMed

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

    2012-01-01

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

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

    PubMed

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

    2015-06-15

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

  18. Behaviour of some organophosphorus and organochlorine pesticides in potatoes during soaking in different solutions.

    PubMed

    Zohair, A

    2001-07-01

    The efficiencies of acidic solutions (radish, citric acid, ascorbic acid, acetic acid and hydrogen peroxide), neutral solutions (sodium chloride) and alkaline solution (sodium carbonate) as well as tap water in the elimination of organochlorine and organophosphorus pesticides from naturally contaminated potatoes were examined. The results indicated that acidic solutions were more effective than neutral and alkaline solutions in the elimination of the organochlorine compounds under investigation, Radish solutions eliminated pesticides completely, except o,p'-DDE (73.1% loss), followed by citric and ascorbic acid solutions. On the other hand, organophosphorus pesticides (pirimphos methyl, malathion and profenofos) were eliminated more by acidic, neutral and alkaline solutions than by organochlorines. The percentage of removal ranged from 98.5 to 100% for pirimphos methyl, 87.9 to 100% for malathion and 100% for profenofos. PMID:11397522

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

    USGS Publications Warehouse

    Smith, M.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.

  20. 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), ...

  1. 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.

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

    PubMed

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

    2015-06-15

    In order to quantitatively examine the lipophilicity of the widely used organophosphorus pesticides (OPs) chlorfenvinphos (CFVP), chlorpyrifos-methyl (CPFM), diazinon (DZN), fenitrothion (FNT), fenthion (FT), isofenphos (IFP), profenofos (PFF) and pyraclofos (PCF), their partition coefficient (Kp) values between phosphatidylcholine (PC) small unilamellar vesicles (SUVs) and water (liposome-water system) were determined by second-derivative spectrophotometry. The second-derivative spectra of these OPs in the presence of PC SUV showed a bathochromic shift according to the increase in PC concentration and distinct derivative isosbestic points, demonstrating the complete elimination of the residual background signal effects that were observed in the absorption spectra. The Kp values were calculated from the second-derivative intensity change induced by addition of PC SUV and obtained with a good precision of R.S.D. below 10%. The Kp values were in the order of CPFM>FT>PFF>PCF>IFP>CFVP>FNT⩾DZN and did not show a linear correlation relationship with the reported partition coefficients obtained using an n-octanol-water system (R(2)=0.530). Also, the results quantitatively clarified the effect of chemical-group substitution in OPs on their lipophilicity. Since the partition coefficient for the liposome-water system is more effective for modeling the quantitative structure-activity relationship than that for the n-octanol-water system, the obtained results are toxicologically important for estimating the accumulation of these OPs in human cell membranes.

  3. 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).

  4. 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

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

    PubMed

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

    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.

  6. 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

  7. 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

  8. Visual detection of organophosphorus pesticides represented by mathamidophos using Au nanoparticles as colorimetric probe.

    PubMed

    Li, Hongkun; Guo, Jiajia; Ping, Hong; Liu, Lurui; Zhang, Minwei; Guan, Fengrui; Sun, Chunyan; Zhang, Qian

    2011-12-15

    With citrate-coated Au nanoparticles as colorimetric probe, a novel visual method for rapid assay of organophosphorus pesticides has been developed. The assay principle is based on catalytic hydrolysis of acetylthiocholine into thiocholine by acetylcholinesterase, which induces the aggregation of Au nanoparticles and the color change from claret-red to purple or even grey. The original plasmon absorption of Au nanoparticles at 522 nm decreases, and simultaneously, a new absorption band appears at 675 nm. The irreversible inhibition of organophosphorus pesticides on acetylcholinesterase prevents aggregation of Au nanoparticles. Under optimum conditions, the absorbance at 522 nm of Au nanoparticles is related linearly to the concentration of mathamidophos in the range of 0.02-1.42 μg/mL with a detection limit of 1.40 ng/mL. This colorimetric method has been successfully utilized to detect mathamidophos in vegetables with satisfactory results. The proposed colorimetric assay exhibits good reproducibility and accuracy, providing a simple and rapid method for the analysis of organophosphorus pesticides.

  9. Concentration of Organochlorine and Organophosphorus Pesticides in Different Molluscs from Tighra Reservoir, Gwalior, India.

    PubMed

    Mamta; Rao, R J; Wani, Khursheed Ahmad

    2015-09-01

    Concentration of organochlorine and organophosphorus pesticides and their metabolites were determined in whole body homogenate of L. acuminata, I. exustus, V. dissimilis, V. bengalensis, from Tighra Reservoir during summer and post monsoon season using GC-MS technique. The different types of pesticides viz., HCB, heptachlor, aldrin, endosulfan, dieldrin, p,p-DDT, choloropyrifos, methyl parathion, dicholorovos, ethion, malathion, parathion were found in resident molluscs studied. Concentration of these pesticides varied independently during the summer and the post monsoon season at monitored sites. The study concluded that presence of pesticides in Tighra Reservoir is a major concern on public and ecosystem health and use of biopesticides in the adjacent area of Reservoir is highly recommended.

  10. 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 ...

  11. 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.

  12. 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.

  13. 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

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

    PubMed

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

    2013-01-01

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

  15. 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.

  16. Pesticides residues in okra (non-target crop) grown close to a watermelon farm in Ghana.

    PubMed

    Essumang, D K; Asare, E A; Dodoo, D K

    2013-09-01

    The study looked at the levels of pesticides in okra grown close to a watermelon farm herein referred to as a non-target crop. The watermelon received some pesticide application in the course of its cultivation, and the okra which was not meant to be sprayed was also affected by the pesticide. About 500 okra samples were collected for a period of 6 weeks and pesticides extracted with 1:1 n-hexane and dichloromethane which was analysed with Agilent 2222 GC/MS coupled with 389 auto-sampler. The results confirmed accumulation of significant levels of pesticides in the non-target crop (okra grown close to watermelon farm). Levels of organochlorine pesticides ranged from 3.10 to 7.60 μg/kg whilst the organophosphorus pesticides had levels ranging from 2.80 to 2016.80 μg/kg. The synthetic pyrethroid pesticide mean levels also ranged from 0.10 to 4.10 μg/kg and were below World Health Organization/Food and Agriculture Organization-recommended residue levels, and though not appearing to constitute a grave threat to life, their occurrence is a concern, and pre-emptive techniques must be developed to thwart the contaminations. Though the non- target crop was not treated directly with the pesticides, some level of contamination with organochlorine and organophosphorus pesticides persisted in the crops. It can be inferred that application of pesticides affected the adjoining crops, meaning that inter-cropping and mix-cropping might not be acceptable when one of the crops requires pesticide application. It is important for the farmers to be trained to ensure proper application of pesticide to minimise its impact on the health of consumers.

  17. 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

  18. Determination of carbamates and organophosphorus pesticides by SDME-GC in natural water.

    PubMed

    López-Blanco, Carmen; Gómez-Alvarez, Sonia; Rey-Garrote, María; Cancho-Grande, Beatriz; Simal-Gándara, Jesús

    2005-10-01

    Water contamination due to the wide variety of pesticides used in agriculture practices is a global environmental pollution problem. Analytical methods with low quantification limits are necessary. The application of a new extraction technique, solvent drop microextraction (SDME), followed by gas chromatography with a nitrogen-phosphorus detector, was assessed for determining carbamates and organophosphorus pesticides in natural water. Experimental parameters which control the performance of SDME such as selection of microextraction solvent, optimization of organic drop volume, effects of sample stirring, salt addition, and, finally, sorption time profiles were studied. Once SDME was optimized, analytical parameters such as linearity (r 2>0.99), precision (<13%), and detection limits (0.2 to 5 microg/L), plus matrix effects were evaluated (no matrix effects were found). SDME is a dynamic technique able to extract pesticides from water in 14 min; the use of organic solvents and water samples for SDME is negligible compared to other extraction techniques. PMID:16132142

  19. The presence of dialkylphosphates in fresh fruit juices: implication for organophosphorus pesticide exposure and risk assessments.

    PubMed

    Lu, C; Bravo, R; Caltabiano, L M; Irish, R M; Weerasekera, G; Barr, D B

    2005-02-13

    This study was designed to determine whether dialkylphosphates (DAPs) are present in fresh fruit juices, as a result of organophosphorus (OP) pesticides degradation. Fresh conventional and organic fruit (apple and orange) juices were purchased from local grocery stores. DAPs were found in both conventional and organic juices, and the original levels were higher, for both apple and orange juices, in conventional than in organic juices. Additional DAPs were found in OP pesticide fortified juices after 72 h of storage at 4 degrees C, suggesting a degradation of OP pesticides in juices. Overall, 12% and 36.2% of fortified azinphosmethyl, a dimethyl OP pesticide, and the combination of fortified diazinon and chlorpyrifos, both diethyl OP pesticides, were degraded to dimethyl and diethyl DAPs, respectively. Although the exact mechanism of the degradation is unknown, hydrolysis is likely the cause of OP pesticide degradation in juice. The presence of DAPs in fresh fruit juices clouds the validity of using urinary DAP measurements for estimating OP pesticide exposures in humans, particularly in children. The overestimated OP pesticide exposures based on urinary DAPs reported in other studies is likely due to the coexistence of preformed DAPs and DAPs resulting from OP pesticide exposures. Thus, before urinary DAP concentrations can be reliably used in exposure and risk assessment, the proportion of the concentration attributable to environmental DAP exposure, particularly through the diet, must be ascertained. In conclusion, urinary DAPs have many limitations when being used as biomarkers for OP pesticides in exposure and risk assessment, and caution should be exercised when interpreting DAPs results.

  20. 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

  1. 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.

  2. 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

  3. [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.

  4. Prophylaxis and post-exposure treatment of intoxications caused by nerve agents and organophosphorus pesticides.

    PubMed

    Kuca, Kamil; Jun, Daniel; Musilek, Kamil; Pohanka, Miroslav; Karasova, Jana Zdarova; Soukup, Ondrej

    2013-12-01

    Treatment of intoxications caused by nerve agents and organophosphorus pesticides consists of different approaches. The first approach is called prophylaxis or pre-exposure administration of antidotes such as cholinesterase reactivators or bioscavengers. The second, post-exposure treatment consists of anticholinergic drugs, acetylcholinesterase reactivators and anticonvulsants. This article is aimed at both mentioned approaches, especially focused on cholinesterase reactivators, which are a broad group of structurally different compounds that can be used in prophylaxis (separately or in combination with butyrylcholinesterase) and also as post-exposure treatment.

  5. Application of a cholinesterase biosensor to screen for organophosphorus pesticides extracted from soil.

    PubMed

    Kumaran, S; Morita, M

    1995-04-01

    Based on the principle of enzyme inactivation, a butyrylcholinesterase (EC 3.1.1.8.) biosensor, to determine some organophosphorus (ORP) pesticides (Fenitrothion, Diazinon, Parathion ethyl, Mevinphos and Heptenophos) in soil extracts, is presented. The enzyme was immobilized on pre-activated Pall Biodyne(TM) transfer membranes, which were physically attached to the sensitive ends of glass pH electrodes. Contact of the enzyme with pesticide samples results in specific inhibition of enzyme activity. Sensor calibration was possible by correlating the inhibition of enzyme activity (monitored by observing reduction in electrode potential changes with substrate additions) with varying concentrations of pesticide compounds in a buffer solution. A simple procedure was designed to extract ORP pesticides from spiked soil samples using a mixture of dichloromethane and acetone as the extraction solvent mixture. The sensor was successfully used to determine pesticide concentrations ranging from a low of 35 ppb (Diazinon) to 21 ppm (Fenitrothion) in soil, with resultant relative standard deviations of percentage enzyme inactivation less than 12%. The complete extraction and analytical procedure is simple, inexpensive and rapid. Mass production of the enzyme membranes and their easy attachment to the electrodes, render them disposable after a single use. The biosensor is seen as a potential analytical instrument for early warning against pesticide contaminations in soil. PMID:18966276

  6. Monitoring of pesticide residues in human milk, soil, water, and food samples collected from Kafr El-Zayat Governorate.

    PubMed

    Dogheim, S M; Mohamed el-Z; Gad Alla, S A; el-Saied, S; Emel, S Y; Mohsen, A M; Fahmy, S M

    1996-01-01

    Pesticide residues in human milk and environmental samples from Kafr El-Zayat Governorate in Egypt were analyzed. This governorate is located near one of the biggest pesticide factories in Egypt. Organochlorine and organophosphorus pesticides were monitored, including those that have been prohibited from use in Egypt. Human milk samples (31 samples) from Kafr El-Zayat were compared with 11 samples collected from Cairo. Data were compared with results from studies performed in 1987 and 1990. The present study showed that aldrin and dieldrin, heptachlor and heptachlor epoxide, and endrin residues have been eliminated from human milk. Estimated daily intakes (EDIs) of DDT complex and gamma-HCH by breast-fed infants in Kafr El-Zayat were 85.96 and 3.1% of the respective acceptable daily intakes (ADIs). beta-HCH residues showed an increasing pattern, especially in human milk samples from Cairo. DDT complex and HCH isomers in orange, spinach, lettuce, potatoes, and clover samples ranged from undetectable to very low concentrations. Higher levels of DDT and HCH were detected, but aldrin, dieldrin, endrin, and the heptachlors were not detected in food of animal origin. Residues in fish samples were below maximum residue limits established by some developed countries. Those in animal milk samples approached the extraneous residue limits of the Codex Committee on Pesticide Residues. HCH residues in soil were negligible, but DDT residues in soil were somewhat higher. Among water samples, groundwater samples had the highest residues of HCHs and DDTs, followed by Nile River water and then tap water. However, the organochlorine pesticide residues were found at concentrations below the maximum allowable limits set by the World Health Organization for drinking water. Among 12 organophosphorus pesticides monitored as parent compounds, dimethoate, malathion, methamidophos, and chlorpyrifos residues were detected in low concentrations in soil samples from a pesticide factory. No

  7. Monitoring of pesticide residues in Egyptian fruits and vegetables during 1996.

    PubMed

    Dogheim, S M; Gad Alla, S A; El-Marsafy, A M

    2001-01-01

    Samples of the most common fruits and vegetables were collected from 8 local markets in 6 governorates. These 1,579 samples were analyzed for residues of 53 pesticides, which included organophosphorus and organonitrogen compounds and some synthetic pyrethroids. Samples were also analyzed for residues of organochlorine pesticides, although they had been prohibited from use several years ago. Only 510 of the 1,579 samples were analyzed for dithiocarbamate pesticide residues, which were determined as CS2. Overall, 76.1 % of the total analyzed samples had no detectable residues, 23.9% contained detectable residues, and 2.59% contained residues that exceeded maximum residue limits. For individual crops, contaminated samples ranged from 0 to 96% of the number of samples analyzed. However, the highest violative percentage for samples of individual crops was 12.5. Chlorpyrifos, carbaryl, dimethoate, bromopropylate, and profenofos were the violative pesticides determined in fruit and vegetable samples. The results of the current study demonstrated that no restricted or banned pesticides such as DDT, HCH, and their isomers were found in any of the samples analyzed. Dithiocarbamate residues were detected in 9.4% of the 510 samples analyzed, with a violative percentage of 0.39, representing one grape sample and one peach sample. PMID:11324620

  8. Early management after self-poisoning with an organophosphorus or carbamate pesticide – a treatment protocol for junior doctors

    PubMed Central

    Eddleston, Michael; Dawson, Andrew; Karalliedde, Lakshman; Dissanayake, Wasantha; Hittarage, Ariyasena; Azher, Shifa; Buckley, Nick A

    2004-01-01

    Severe organophosphorus or carbamate pesticide poisoning is an important clinical problem in many countries of the world. Unfortunately, little clinical research has been performed and little evidence exists with which to determine best therapy. A cohort study of acute pesticide poisoned patients was established in Sri Lanka during 2002; so far, more than 2000 pesticide poisoned patients have been treated. A protocol for the early management of severely ill, unconscious organophosphorus/carbamate-poisoned patients was developed for use by newly qualified doctors. It concentrates on the early stabilisation of patients and the individualised administration of atropine. We present it here as a guide for junior doctors in rural parts of the developing world who see the majority of such patients and as a working model around which to base research to improve patient outcome. Improved management of pesticide poisoning will result in a reduced number of suicides globally. PMID:15566582

  9. 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

  10. 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.

  11. A gold-based nanobeacon probe for fluorescence sensing of organophosphorus pesticides.

    PubMed

    Dou, Xiaowen; Chu, Xianfeng; Kong, Weijun; Luo, Jiaoyang; Yang, Meihua

    2015-09-01

    A nanomaterials-based novel molecular beacon has attracted growing attentions in fluorescent assays as many nanomaterials possess excellent quenching efficiency. In this work, a gold-based nanobeacon probe was established to detect organophosphorus pesticides for the first time. The constructed gold-based nanobeacon acted as a signal indicator and could display the decreasing of the intensity in the presence of targets, which competitively bound to single strand DNA. To achieve a high sensitive probe, some parameters including solution pH, temperature and reaction time were investigated and optimized. The gold-based nanobeacon probe assay was proved to be rapid and sensitive to achieve a detection limit of 0.035 μM for isocarbophos, 0.134 μM for profenofos, 0.384 μM for phorate and 2.35 μM for omethoate, respectively. The prepared nanobeacon effectively reduced the background and improved the detection sensitivity and selectivity. The probe is stable, easy to operate and does not need sophisticated instruments. These features makes the probe feasible for screening trace organophosphorus pesticides in real samples.

  12. A gold-based nanobeacon probe for fluorescence sensing of organophosphorus pesticides.

    PubMed

    Dou, Xiaowen; Chu, Xianfeng; Kong, Weijun; Luo, Jiaoyang; Yang, Meihua

    2015-09-01

    A nanomaterials-based novel molecular beacon has attracted growing attentions in fluorescent assays as many nanomaterials possess excellent quenching efficiency. In this work, a gold-based nanobeacon probe was established to detect organophosphorus pesticides for the first time. The constructed gold-based nanobeacon acted as a signal indicator and could display the decreasing of the intensity in the presence of targets, which competitively bound to single strand DNA. To achieve a high sensitive probe, some parameters including solution pH, temperature and reaction time were investigated and optimized. The gold-based nanobeacon probe assay was proved to be rapid and sensitive to achieve a detection limit of 0.035 μM for isocarbophos, 0.134 μM for profenofos, 0.384 μM for phorate and 2.35 μM for omethoate, respectively. The prepared nanobeacon effectively reduced the background and improved the detection sensitivity and selectivity. The probe is stable, easy to operate and does not need sophisticated instruments. These features makes the probe feasible for screening trace organophosphorus pesticides in real samples. PMID:26388389

  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. [Cumulative exposure to pesticide residues in food].

    PubMed

    Kostka, Grazyna; Urbanek-Olejnik, Katarzyna; Liszewska, Monika

    2011-01-01

    The results of food monitoring studies indicate that humans are constantly exposed to residues ofplant protection products (pesticides) in marketed food products. Hence, assessment of the risk to consumers associated with the consumption of products containing residues of the active substances of pesticides is a key stage in both the registration of pesticides and official control of foodstuffs. However there are frequent cases of exposure not only to individual active substances but also to mixtures of pesticide residues. These levels are usually low, below of effective action, and interaction such as synergism orpotentiation is not expected to occur At the same time, literature data indicate that for mixtures sharing a common MOA (Mode of Action/Mechanism of Action), the probability of additive effects is high, even after adjusting for the low levels of the mixed pesticide residues present. Accordingly, health risk assessment for consumers exposed to such mixtures (cumulative/aggregate risk) has become an issue of topical importance. EU-level initiatives regarding the development of appropriate methodology for the estimation of cumulative/aggregate risk have brought about considerable progress in this area. The article discusses various aspects of estimation of cumulative risk for consumers associated with exposure to mixtures of pesticide residues in food.

  15. 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 ...

  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. [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.

  18. [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

  19. 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

  20. Dialkyl phosphate metabolites of organophosphorus in applicators of agricultural pesticides in Majes – Arequipa (Peru)

    PubMed Central

    Yucra, Sandra; Steenland, Kyle; Chung, Arturo; Choque, Fredy; Gonzales, Gustavo F

    2006-01-01

    Background Organophosphorus (OPs) pesticides are the most commonly used pesticides in Peruvian agriculture. The population at risk for OPs exposure includes formulators, applicators and farmers. Majes Valley is the most important agricultural center of the Southern region of Peru. The present study was aimed to determine the knowledge about using OPs, safety practice and urinary dialkylphosphate metabolites on OP applicators in the Majes Valley, Peru. Methods This study was based on a questionnaire which included socio-demographic characteristics, knowledge of safety practices to handling OPs, characteristics of pesticide application and use of protective measures to avoid pesticide contamination. Exposure was assessed by measuring six urinary OP metabolites (DMP, DMTP, DMDTP, DEP, DETP, and DEDTP) by gas chromatography using a single flame photometric detector. The sample consisted of 31 men and 2 women aged 20 – 65 years old. Results 76% of applicators had at least one urinary dialkylphosphate metabolite above the limit of detection. The geometric mean (GM) and the geometric standard deviation (GSD) of DMP and DEP were 5.73 ug/g cr. (GSD 2.51), and 6.08 ug/g cr. (GSD 3.63), respectively. The percentage of applicators with detectable DMP, DMDTP, and DMTP in urine was 72.72%, 3.03%, and 15.15%, respectively, while the corresponding figures for DEP, DETP, and DEDTP were 48.48%, 36.36% and 15.15%, respectively. There was no significant association between the use of protection practices and the absence of urine OPs metabolites suggesting inadequate protection practices. Conclusion The pesticide applicators in Majes Valley have significant exposure to OP pesticides, probably due to inappropriate protective practices. Future work should evaluate possible health effects. PMID:17177990

  1. Effects of a provincial ban of two toxic organophosphorus insecticides on pesticide poisoning hospital admissions

    PubMed Central

    2012-01-01

    Background. Pesticide self-poisoning causes one third of global suicides. Sri Lanka halved its suicide rate by banning WHO Class I organophosphorus (OP) insecticides and then endosulfan. However, poisoning with Class II toxicity OPs, particularly dimethoate and fenthion, remains a problem. We aimed to determine the effect and feasibility of a ban of the two insecticides in one Sri Lankan district. Methods. Sale was banned in June 2003 in most of Polonnaruwa District, but not Anuradhapura District. Admissions with pesticide poisoning to the district general hospitals was prospectively recorded from 2002. Results. Hospital admissions for dimethoate and fenthion poisoning fell by 43% after the ban in Polonnaruwa, while increasing by 23% in Anuradhapura. The pesticide case fatality fell from 14.4% to 9.0% in Polonnaruwa (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.41–0.84) and 11.3% to 10.6% in Anuradhapura (OR 0.93, 95%CI 0.70–1.25; p = 0.051). This reduction was not sustained, with case fatality in Polonnaruwa rising to 12.1% in 2006–2007. Further data analysis indicated that the fall in case fatality had actually been due to a coincidental reduction in case fatality for pesticide poisoning overall, in particular for paraquat poisoning. Conclusions. We found that the insecticides could be effectively banned from agricultural practice, as shown by the fall in hospital admissions, with few negative consequences. However, the ban had only a minor effect on pesticide poisoning deaths because it was too narrow. A study assessing the agricultural and health effects of a more comprehensive ban of highly toxic pesticides is necessary to determine the balance between increased costs of agriculture and reduced health care costs and fewer deaths. PMID:22372788

  2. Organophosphorus pesticide exposure of urban and suburban preschool children with organic and conventional diets.

    PubMed Central

    Curl, Cynthia L; Fenske, Richard A; Elgethun, Kai

    2003-01-01

    We assessed organophosphorus (OP) pesticide exposure from diet by biological monitoring among Seattle, Washington, preschool children. Parents kept food diaries for 3 days before urine collection, and they distinguished organic and conventional foods based on label information. Children were then classified as having consumed either organic or conventional diets based on analysis of the diary data. Residential pesticide use was also recorded for each home. We collected 24-hr urine samples from 18 children with organic diets and 21 children with conventional diets and analyzed them for five OP pesticide metabolites. We found significantly higher median concentrations of total dimethyl alkylphosphate metabolites than total diethyl alkylphosphate metabolites (0.06 and 0.02 micro mol/L, respectively; p = 0.0001). The median total dimethyl metabolite concentration was approximately six times higher for children with conventional diets than for children with organic diets (0.17 and 0.03 micro mol/L; p = 0.0003); mean concentrations differed by a factor of nine (0.34 and 0.04 micro mol/L). We calculated dose estimates from urinary dimethyl metabolites and from agricultural pesticide use data, assuming that all exposure came from a single pesticide. The dose estimates suggest that consumption of organic fruits, vegetables, and juice can reduce children's exposure levels from above to below the U.S. Environmental Protection Agency's current guidelines, thereby shifting exposures from a range of uncertain risk to a range of negligible risk. Consumption of organic produce appears to provide a relatively simple way for parents to reduce their children's exposure to OP pesticides. PMID:12611667

  3. Bioremediation of organophosphorus pesticides by surface-expressed carboxylesterase from mosquito on Escherichia coli.

    PubMed

    Zhang, Jianliang; Lan, Wensheng; Qiao, Chuanling; Jiang, Hong; Mulchandani, Ashok; Chen, Wilfred

    2004-01-01

    The insecticide resistance-associated esterase, carboxylesterase B1 (CaE B1), from mosquito was used to degrade the organophosphorus compounds. To eradicate the need for enzyme purification and minimize the resistance to mass transport of the substrate and product across the cell membranes, the CaE B1 was displayed on the cell surface of Escherichia coli fused to the C-terminus of the ice nucleation protein (INP). The presence of CaE B1 on the bacterial cell surface was verified by SDS-PAGE, Western blotting analysis, and immunofluorescence microscopy. More than 50% of active CaE B1 is exported across the membrane and anchored onto the cell surface as determined by proteinase accessibility and cell fractionation experiments. In contrast, only a 6% drop in activity for proteinase K-treated cells was detected from E.coli cells containing pET-B1. From the degradation experiment, more than 80% of the malathion was degraded by whole cells containing plasmid pUC-NC-B1. Constitutive expression of CaE B1 on the surface using INPNC resulted in no cell lysis, and the suspended cultures also exhibited good stability. Because of their high biodegradation activity and superior stability, these "live biocatalysts" are promising for detoxification of organophosphorus pesticides. PMID:15458345

  4. Potential Uses of Biomonitoring Data: A Case Study Using the Organophosphorus Pesticides Chlorpyrifos and Malathion

    PubMed Central

    Barr, Dana B.; Angerer, Jürgen

    2006-01-01

    Background Organophosphorus pesticides such as chlorpyrifos and malathion are widely used insecticides. They do not bioaccumulate appreciably in humans and are rapidly metabolized and excreted in the urine. In nonoccupational settings, exposures to these pesticides are typically sporadic and short-lived because the pesticides tend to degrade in the environment over time; however, dietary exposures may be more chronic. Biologic monitoring has been widely used to assess exposures, susceptibility, and effects of chlorpyrifos and malathion; thus, the information base on these compounds is data rich. For biomonitoring of exposure, chlorpyrifos and malathion have been measured in blood, but most typically their urinary metabolites have been measured. For assessing early effects and susceptibility, cholinesterase and microsomal esterase activities, respectively, have been measured. Objectives Although many biologic monitoring data have been generated and published on these chemicals, their interpretation is not straightforward. For example, exposure to environmental degradates of chlorpyrifos and malathion may potentially increase f urinary metabolite levels, thus leading to overestimation of exposure. Also, the temporal nature of the exposures makes the evaluation of both exposure and effects difficult. We present an overview of the current biomonitoring and other relevant data available on exposure to chlorpyrifos and malathion and the use of these data in various environmental public health applications. PMID:17107865

  5. 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

  6. 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

  7. 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

  8. Method validation of resistive heating--gas chromatography with flame photometric detection for the rapid screening of organophosphorus pesticides in fruit and vegetables.

    PubMed

    Patel, Katan; Fussell, Richard J; Macarthur, Roy; Goodall, David M; Keely, Brendan J

    2004-08-13

    A rapid method for the screening of organophosphorus (OP) pesticides in fruit and vegetables is reported. Sample extracts were analysed using resistive heating-gas chromatography (RH-GC) with flame photometric detection (FPD). A CarboFrit insert in the GC liner allowed injection of crude extracts onto the GC system. Separation of up to 20 pesticides was achieved in 4.3 min with excellent retention time stability. Signal-to-noise ratios of 5:1 or better were obtained for the majority of the pesticides at the lowest calibrated level (LCL), 0.01 microg ml(-1), with excellent linearity over the range 0.01-0.5 microg ml(-1) (0.004-0.2 mg kg(-1) equivalent). Average recoveries between 70 and 116% were obtained for pesticides spiked at 0.01 and 0.1 mg kg(-1) with associated R.S.D. values < or =20% in the majority of cases. Estimates of relative reproducibility standard deviation (R.S.D.(R)), made by combining observed R.S.D. values with estimates of uncertainty associated with mean recovery allowed the determination of HORRAT values which confirmed that the method is capable of producing results which are fit for purpose. The validated method was then used to screen peaches, grapes and sweet peppers for a total of 37 pesticides. Incurred residue results obtained using RH-GC-FPD were in good agreement with the results from analysis of the same samples using MS confirmation.

  9. 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.

  10. Chronic dietary risk for pesticide residues in food in Brazil: an update.

    PubMed

    Caldas, E D; Souza, L C K R

    2004-11-01

    The objective was to conduct a dietary risk assessment of pesticides registered in Brazil up to 14 January 2004. The theoretical maximum daily intake (TMDI) was calculated for 275 compounds using the Brazilian maximum residue limits (MRL) and food consumption. The chronic dietary risk assessment was conducted by comparing the TMDI with the Brazilian acceptable daily intake (ADI) or, when not available, with the ADI from other sources. The TMDI was higher than the ADI (%ADI>100) in at least one Brazilian region for eight pesticides, including five organophosphorus insecticides. For these compounds, the higher TMDI (expressed as %ADI) ranged from 140 (metam sodium) to 14,000 (methyl bromide). Rice, beans, citrus and tomato were the commodities that contributed most to ingestion. Change in pesticide use patterns and the establishment of ADIs by the Brazilian government have reduced the number of compounds for which the TMDI exceeded the ADI in the last 4 years. Risk assessment methodology based on TMDI calculation, however, is conservative as it assumes that the food supply is always treated with all the registered pesticides for that crop and that one always consumes food containing residues at the tolerance level. Furthermore, for six compounds with TMDI exceeding the ADI, a more realistic estimation of the pesticide daily intake was conducted using monitoring residue data from the Brazilian National Pesticide Residue Program. For these compounds, the higher refined intakes ranged from 2% (dimethoate) to 180% (fenitrothion) of the ADIs. The implementation of a national pesticide residue monitoring programme by the government was important to allow the refinement of the risk assessment. However, adequate daily food consumption data are still needed to assess better the public health risk to Brazilian consumers from food produced from crops treated with pesticides.

  11. 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...

  12. 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...

  13. Decay study of pesticide residues in apple samples.

    PubMed

    Pérez Clavijo, M; Plaza Medina, M; Sanz Asensio, J; Galbán Bernal, J

    1996-07-26

    A method for monitoring pesticides in apple samples, including Soxhlet extraction, an evaporation step and capillary gas chromatography with nitrogen-phosphorus detection, is applied to a decay study of the carbamate pesticide ethiofencarb. The evaporation step is carried out by a surface nitrogen flow and the recoveries of ethiofencarb measured in standard solutions of ethyl acetate and apple extracts. The results of the decay studies show that ethiofencarb is degraded in the apple peel faster than in the interior of the fruit. The methodology is then applied to decay studies in the laboratory of the organophosphorus pesticides, diclofluanid, fenitrothion and malathion.

  14. Pesticide residues survey in citrus fruits.

    PubMed

    Ortelli, Didier; Edder, Patrick; Corvi, Claude

    2005-05-01

    The use of pesticides is widespread in citrus fruits production for pre- and post-harvest protection and many chemical substances may be applied in order to control undesirable moulds or insects. A survey was carried out to evaluate levels of pesticide residues in citrus fruits. Two multiresidue analytical methods were used to screen samples for more than 200 different fungicides, insecticides and acaricides. A total of 240 samples of citrus fruits including lemon, orange, mandarin, grapefruit, lime, pomelo and kumquat were taken in various markets in the Geneva area during the year 2003. Ninety-five percent of the 164 samples issued from classical agriculture contained pesticides and 38 different compounds have been identified. This high percentage of positive samples was mainly due to the presence of two post-harvest fungicides, imazalil and thiabendazole, detected in 70% and 36% of samples respectively. Only three samples exceeded the Swiss maximum residue limits (MRLs). Fifty-three samples sold with the written indication "without post-harvest treatment" were also controlled. Among theses samples, three exceeded the Swiss MRLs for penconazole or chlorpyrifos and 18 (34%) did not respect the written indication since we found large amounts of post-harvest fungicides. Finally, 23 samples coming from certified organic production were analysed. Among theses samples, three contained small amounts of pesticides and the others were pesticides free.

  15. Pesticide residues in oranges from Valencia (Spain).

    PubMed

    Fernández, M; Picó, Y; Mañes, J

    2001-07-01

    One hundred and fifty citrus samples from an agricultural co-operative of the Valencian Community (Spain) were analysed for pre- and post-harvest pesticide residues using high performance liquid chromatography and gas chromatography. Among the residues from post-harvest treatments, imazalil was detected in 112 (74.7%) samples at a mean level of 1.2 mg/kg, thiabendazole in 21 (14.0%) samples at a mean level of 0.47 mg/kg and carbendazim in 5 (3.3%) samples at a mean level of 1.05 mg/kg. Among the residues from pre-harvest treatment, dicofol was detected in 28 (18.7%) samples at a mean level of .28 mg/kg chlorpyriphos in 19 (12.7% samples at a mean level of 0.16 mg/kg and endosulfan in 11 (7.3%) at a mean level of 0.27 mg/kg. Most of the samples contained residues of various pesticides and six samples (4.0%) exceeded the European Union Maximum Residue Limit (MRL). The pesticides that surpassed the MRLs were chlorpyriphos in five samples and dicofol in one.

  16. Monitoring of seasonal vegetables for pesticide residues.

    PubMed

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

    2002-03-01

    Market samples (60) of six seasonal vegetables were monitored during 1996-1997 to determine the magnitude of pesticidal contamination. The estimation of insecticide residues representing four major chemical groups i.e. organochlorine, organophosphorous, synthetic pyrethroid and carbamate, was done by adopting a multiresidue analytical technique employing GC-ECD and GC-NPD systems with capillary columns. The tested samples showed 100% contamination with low but measurable amounts of residues. Among the four chemical groups, the organophosphates were dominant followed by organochlorines, synthetic pyrethroids and carbamates. About 23% of the samples showed contamination with organophosphorous compounds above their respective MRL values. More extensive studies covering different regions of Haryana state are suggested to get a clear idea of the magnitude of vegetable contamination with pesticide residues.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. Survey of pesticide residues in table grapes: determination of processing factors, intake and risk assessment.

    PubMed

    Poulsen, M E; Hansen, H K; Sloth, J J; Christensen, H B; Andersen, J H

    2007-08-01

    The differences in residue pattern between Italy and South Africa, the main exporters of table grapes to the Danish market, were investigated. The results showed no major differences with respect to the number of samples with residues, with residues being found in 54-78% of the samples. Exceedances of the European Union maximum residue limit (MRL) were found in five samples from Italy. A number of samples were rinsed to study the possible reduction of residues. For copper, iprodione, procymidone and dithiocarbamates a significant effect of rinsing was found (20-49% reduction of residues). However, no significant effect was found for organophosphorus pesticides and pyrethroids, whereas the number of samples with residues of benzilates, phenylamids and triazoles was insufficient to demonstrate any significant effects. An intake calculation showed that the average intake from Italian grapes was 3.9 microg day(-1) for pesticides and 21 microg day(-1) for copper. Correspondingly, the intakes from South African grapes were 2.6 and 5.7 microg day(-1), respectively. When the total exposure of pesticides from grapes were related to acceptable daily intake, expressed as the sum of Hazard Quotients, the exposure were approximately 0.5% for Italian samples and 1% for South African samples. PMID:17613076

  2. 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

  3. 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

  4. Binary combinations of organophosphorus pesticides exhibit differential toxicity under oxidised and un-oxidised conditions.

    PubMed

    Arora, Sumitra; Kumar, Anu

    2015-05-01

    Acetylcholinesterase (AChE) inhibition has been demonstrated to be useful as a biomarker for exposure to organophosphorus (OP) insecticides in many environments. The objective of this study was to investigate the response of housefly (Musca domestica) head AChE (HF-AChE) exposed to five OPs as individual compounds and their binary mixtures under in vitro conditions. To examine the effects of oxidation on OP potency in the HF-AChE system, bromine water was used as an oxidisng agent. With oxidation, the sensitivity of HF-AChE to chlorpyrifos (CPF), malathion (MLT) and triazophos (TRZ) increased significantly. Monocrotophos (MCP) and profenofos (PRF) did not exhibit any significant differences in toxicity under oxidised and un-oxidised conditions. The toxicological interaction of five organophosphorus pesticides was evaluated using the concentration addition model, the combination index-isobologram equation and the toxic unit approach. All three models provided similar predictions for the 10 binary combinations of OPs under oxidised and un-oxidised conditions. In the present study, the antagonistic effects of the binary combination of OPs (CPF+PRF, CPF+MLT, MCP+MLT, PRF+MLT, MLT+TRZ and PRF+TRZ) were observed under oxidised conditions. This may be due to dispositional and/or receptor antagonism. Most of the binary combinations assayed under un-oxidised conditions exhibited synergistic responses. Triazophos showed very strong synergism in binary combinations with CPF, MCP and PRF un-oxidised conditions. In contrast, under oxidised conditions, only CPF+TRZ exhibited synergism. The results obtained indicate differential toxicity of binary combinations of OPs under oxidised and un-oxidised conditions. This information could be a valuable tool in understanding the mechanisms of OPs interactions and the interpretation of future in vivo studies with mixtures of OP insecticides.

  5. 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.

  6. Microwave-assisted extraction at atmospheric pressure coupled to different clean-up methods for the determination of organophosphorus pesticides in olive and avocado oil.

    PubMed

    Fuentes, Edwar; Báez, María E; Díaz, Juan

    2009-12-18

    An effective extraction method was devised for the determination of organophosphorus pesticides (OPPs) in olive and avocado oil samples, using atmospheric pressure microwave-assisted liquid-liquid extraction (APMAE) and solid-phase extraction or low-temperature precipitation as clean-up step. A simple glass system equipped with an air-cooled condenser was designed as an extraction vessel. The pesticides were partitioned between acetonitrile and oil solution in hexane. Analytical determinations were carried out by gas chromatography-flame photometric detection and gas chromatography-tandem mass spectrometry, using a triple quadrupole mass analyzer, for confirmation purposes. Several factors influencing the extraction efficiency were investigated and optimized through fractional factorial design and Doehlert design. Under optimal conditions the recovery of pesticides from oil at 0.025 microg g(-1) ranged from 71% to 103%, except for fenthion in avocado oil, with RSDs < or = 13% (n=5). The LOQ for the entire method ranged from 0.004 to 0.015 microg g(-1). Finally, the proposed method was successfully applied to the extraction and determination of the selected pesticides in 20 commercially packed extra virgin olive oils and four commercially packed avocado oils produced in Chile. Detectable residues of different OPPs were observed in 85% of samples. PMID:19926091

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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.

  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. 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

  14. 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.

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

    PubMed

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

    2012-04-11

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

  16. 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

  17. Nonaqueous and aqueous-organic media for the enantiomeric separations of neutral organophosphorus pesticides by CE.

    PubMed

    Huang, Lu; Lin, Jinming; Xu, Liangjun; Chen, Guonan

    2007-08-01

    The enantiomeric separation of some poorly water-soluble organophosphorus pesticides (OPs) has been investigated using nonaqueous solvent and aqueous-organic solvent systems. In this work, sodium cholate (SC) either with SDS or gamma-CD was used to achieve enantiomeric separations of four neutral and poorly water-soluble OPs, i.e., profenofos, prothiofos, sulprofos, and pyraclofos. Electrophoretic medium consisted of a mixture of methanol (MeOH) with ACN (4:1 v/v) or a mixture of MeOH with H(2)O and ACN (5:4:1 v/v/v). On one hand, NACE was applied for enantiomeric separation of pyraclofos using a large amount of chiral and achiral surfactants (SC and SDS). On the other hand, H(2)O was added to act as a solvent additive to increase the solubility of gamma-CD in the organic solvents such as MeOH and ACN, in which the solubility of gamma-CD was very low. The presence of H(2)O was found to be particularly useful for the enantiomeric separation of profenofos, prothiofos, and sulprofos. In this way, the range of application of the neutral CDs in CE has been extended. In addition, SC was used as the only electrolyte. The proposed method has been applied for the analysis of soil samples. PMID:17592615

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

    PubMed

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

    2012-08-01

    We demonstrate a facile procedure to efficiently prepare Prussian blue nanocubes/reduced graphene oxide (PBNCs/rGO) nanocomposite by directly mixing Fe(3+) 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 over-potential decreases ∼460 mV compared to that on a bare electrode, suggesting that PBNCs/rGO has a high electrocatalytic activity towards the oxidation of thiocholine. The AChE biosensor shows rapid response and high sensitivity for detection of monocrotophos with a linear range from 1.0 to 600 ng mL(-1) and a detection limit of 0.1 ng mL(-1). 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.

  19. Pesticide residues in birds and mammals

    USGS Publications Warehouse

    Stickel, L.F.; Edwards, C.A.

    1973-01-01

    SUMMARY: Residues of organochlorine pesticides and their breakdown products are present in the tissues of essentially all wild birds throughout the world. These chemicals accumulate in fat from a relatively small environmental exposure. DDE and dieldrin are most prevalent. Others, such as heptachlor epoxide, chlordane, endrin, and benzene hexachloride also occur, the quantities and kinds generally reflecting local or regional use. Accumulation may be sufficient to kill animals following applications for pest control. This has occurred in several large-scale programmes in the United States. Mortality has also resulted from unintentional leakage of chemical from commercial establishments. Residues may persist in the environment for many years, exposing successive generations of animals. In general, birds that eat other birds, or fish, have higher residues than those that eat seeds and vegetation. The kinetic processes of absorption, metabolism, storage, and output differ according to both kind of chemical and species of animal. When exposure is low and continuous, a balance between intake and excretion may be achieved. Residues reach a balance at an approximate animal body equilibrium or plateau; the storage is generally proportional to dose. Experiments with chickens show that dieldrin and heptachlor epoxide have the greatest propensity for storage, endrin next, then DDT, then lindane. The storage of DDT was complicated by its metabolism to DDE and DDD, but other studies show that DDE has a much greater propensity for storage than either DDD or DDT. Methoxychlor has little cumulative capacity in birds. Residues in eggs reflect and parallel those in the parent bird during accumulation, equilibrium, and decline when dosage is discontinued. Residues with the greatest propensity for storage are also lost most slowly. Rate of loss of residues can be modified by dietary components and is speeded by weight loss of the animal. Under sublethal conditions of continuous

  20. 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.

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

    PubMed

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

    2013-01-01

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

  2. 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.

  3. Is oxygen required before atropine administration in organophosphorus or carbamate pesticide poisoning? – A cohort study

    PubMed Central

    Konickx, L. A.; Bingham, K.

    2014-01-01

    Background Early and adequate atropine administration in organophosphorus (OP) or carbamate insecticide poisoning improves outcome. However, some authors advise that oxygen must be given before atropine due to the risk of inducing ventricular dysrhythmias in hypoxic patients. Because oxygen is frequently unavailable in district hospitals of rural Asia, where the majority of patients with insecticide poisoning present, this guidance has significant implications for patient care. The published evidence for this advice is weak. We therefore performed a patient cohort analysis to look for early cardiac deaths in patients poisoned by anticholinesterase pesticides. Methods We analysed a prospective Sri Lankan cohort of OP or carbamate-poisoned patients treated with early atropine without the benefit of oxygen for evidence of early deaths. The incidence of fatal primary cardiac arrests within 3 h of admission was used as a sensitive (but non-specific) marker of possible ventricular dysrhythmias. Results The cohort consisted of 1957 patients. The incidence of a primary cardiac death within 3 h of atropine administration was 4 (0.2%) of 1957 patients. The majority of deaths occurred at a later time point from respiratory complications of poisoning. Conclusion We found no evidence of a high number of early deaths in an observational study of 1957 patients routinely given atropine before oxygen that might support guidance that oxygen must be given before atropine. The published literature indicates that early and rapid administration of atropine during resuscitation is life-saving. Therefore, whether oxygen is available or not, early atropinisation of OP- and carbamate-poisoned patients should be performed. PMID:24810796

  4. Organophosphorus Pesticides Decrease M2 Muscarinic Receptor Function in Guinea Pig Airway Nerves via Indirect Mechanisms

    PubMed Central

    Proskocil, Becky J.; Bruun, Donald A.; Thompson, Charles M.; Fryer, Allison D.; Lein, Pamela J.

    2010-01-01

    Background Epidemiological studies link organophosphorus pesticide (OP) exposures to asthma, and we have shown that the OPs chlorpyrifos, diazinon and parathion cause airway hyperreactivity in guinea pigs 24 hr after a single subcutaneous injection. OP-induced airway hyperreactivity involves M2 muscarinic receptor dysfunction on airway nerves independent of acetylcholinesterase (AChE) inhibition, but how OPs inhibit neuronal M2 receptors in airways is not known. In the central nervous system, OPs interact directly with neurons to alter muscarinic receptor function or expression; therefore, in this study we tested whether the OP parathion or its oxon metabolite, paraoxon, might decrease M2 receptor function on peripheral neurons via similar direct mechanisms. Methodology/Principal Findings Intravenous administration of paraoxon, but not parathion, caused acute frequency-dependent potentiation of vagally-induced bronchoconstriction and increased electrical field stimulation (EFS)-induced contractions in isolated trachea independent of AChE inhibition. However, paraoxon had no effect on vagally-induced bradycardia in intact guinea pigs or EFS-induced contractions in isolated ileum, suggesting mechanisms other than pharmacologic antagonism of M2 receptors. Paraoxon did not alter M2 receptor expression in cultured cells at the mRNA or protein level as determined by quantitative RT-PCR and radio-ligand binding assays, respectively. Additionally, a biotin-labeled fluorophosphonate, which was used as a probe to identify molecular targets phosphorylated by OPs, did not phosphorylate proteins in guinea pig cardiac membranes that were recognized by M2 receptor antibodies. Conclusions/Significance These data indicate that neither direct pharmacologic antagonism nor downregulated expression of M2 receptors contributes to OP inhibition of M2 function in airway nerves, adding to the growing evidence of non-cholinergic mechanisms of OP neurotoxicity. PMID:20479945

  5. 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

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

    PubMed Central

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

    2012-01-01

    Organophosphorus (OP) insecticide self-poisoning is responsible for about one-quarter of global suicides. Treatment focuses on the fact that OP compounds inhibit acetylcholinesterase (AChE); however, AChE-reactivating drugs do not benefit poisoned humans. We therefore studied the role of solvent coformulants in OP toxicity in a novel minipig model of agricultural OP poisoning. Gottingen minipigs were orally poisoned with clinically relevant doses of agricultural emulsifiable concentrate (EC) dimethoate, dimethoate active ingredient (AI) alone, or solvents. Cardiorespiratory physiology and neuromuscular (NMJ) function, blood AChE activity, and arterial lactate concentration were monitored for 12 h to assess poisoning severity. Poisoning with agricultural dimethoate EC40, but not saline, caused respiratory arrest within 30 min, severe distributive shock and NMJ dysfunction, that was similar to human poisoning. Mean arterial lactate rose to 15.6 [SD 2.8] mM in poisoned pigs compared to 1.4 [0.4] in controls. Moderate toxicity resulted from poisoning with dimethoate AI alone, or the major solvent cyclohexanone. Combining dimethoate with cyclohexanone reproduced severe poisoning characteristic of agricultural dimethoate EC poisoning. A formulation without cyclohexanone showed less mammalian toxicity. These results indicate that solvents play a crucial role in dimethoate toxicity. Regulatory assessment of pesticide toxicity should include solvents as well as the AIs which currently dominate the assessment. Reformulation of OP insecticides to ensure that the agricultural product has lower mammalian toxicity could result in fewer deaths after suicidal ingestion and rapidly reduce global suicide rates. PMID:22365945

  7. 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.

  8. [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.

  9. 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...

  10. 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.

  11. 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

  12. 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.

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

    PubMed

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

    2014-11-01

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

  14. 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...

  15. 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...

  16. 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...

  17. 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

  18. [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

  19. Predicting Outcome using Butyrylcholinesterase Activity in Organophosphorus Pesticide Self-Poisoning

    PubMed Central

    Eddleston, Michael; Eyer, Peter; Worek, Franz; Rezvi Sheriff, MH; Buckley, Nick A

    2008-01-01

    Background The usefulness of a low butyrylcholinesterase activity on admission for predicting severity in acute organophosphorus insecticide poisoning has long been debated. Previous studies have been confounded by the inclusion of multiple insecticides with differing inhibitory kinetics. Aim We aimed to assess the usefulness of admission butyrylcholinesterase activity, together with plasma organophosphorus concentration, for predicting death with identified organophosphorus insecticides. Design A prospective cohort of self-poisoned patients Methods We prospectively studied 91 and 208 patients with proven dimethoate or chlorpyrifos self-poisoning treated using a standard protocol. Plasma butyrylcholinesterase activity and organophosphorus concentration were measured on admission and clinical outcomes recorded. Results The usefulness of a plasma butyrylcholinesterase activity <600mU/ml on admission varied markedly - while highly sensitive in chlorpyrifos poisoning (sensitivity 11/11 deaths; 100%, 95%CI 71.5-100), its specificity was only 17.7% (95%CI 12.6-23.7). In contrast, while poorly sensitive for deaths in dimethoate poisoning (12/25 patients; 48%, 95%CI 27.9-68.7) it was reasonably specific (86.4%, 95%CI 75.7-93.6). A high organophosphorus concentration on admission was associated with worse outcome; however, a clear threshold concentration was only present for dimethoate poisoning. Conclusions Plasma butyrylcholinesterase activity on admission can provide useful information; however, it must be interpreted carefully. It can only be used to predict need for critical care and death when the insecticide ingested is known and its sensitivity and specificity for that insecticide has been studied. Plasma concentration of some organophosphorus insecticides predicts outcome. The development of rapid bedside tests for organophosphorus detection may aid early assessment of severity. PMID:18375477

  20. 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

  1. Regulatory approaches for controlling pesticide residues in food animals.

    PubMed

    Landy, R B; Kim, I S; Lee, Y; Hoffman, M K

    1999-03-01

    Pesticide use is vital to the production of an economical, high-quality food supply throughout the world. The regulatory system in the United States is designed to prevent the entry of unacceptable residues into the food supply. To address the complexities associated with pesticide use, the regulatory apparatus is composed of several federal and numerous state agencies. Based on monitoring results, it appears that most pesticides are being used in the appropriate manner and that thresholds for pesticides, deemed to be adequate to protect human health, are seldom exceeded. With our increasing knowledge of the public health and ecologic threats posed by pesticide residues, our approach to regulating pesticides will continue to evolve.

  2. [Transfer of pesticide residues to crops via cardboard boxes].

    PubMed

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

    2009-10-01

    Cardboard boxes used to transport crops are often reused in the distribution process, and therefore transfer of pesticides between crops might occur. So, we designed model experiments to investigate whether or not transfer of pesticide residues from crops to other crops via cardboard boxes occurs. Under severe experimental conditions, 6.2% of the pesticide residues of grapefruit was found to be transferred to spinach via cardboard boxes. In the case of the mandarin orange, 0.57% was transferred. The actual amount of transferred pesticides in the market may be less than that in these model experiments, but it is clear that transfer of pesticide residues to other crops via cardboard boxes can occur. Therefore more attention must be given to reuse of cardboard boxes in the distribution process. PMID:19897948

  3. 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

  4. Recovery evaluation of organophosphorus pesticides from bee pollen by matrix solid-phase dispersion extraction using sorbents based on silica and titania

    NASA Astrophysics Data System (ADS)

    Torres-Perea, C.; Muñoz-Rodríguez, D.; Medina-Peralta, S.; Carrera-Figueiras, C.; Moguel-Ordóñez, Y. B.

    2013-06-01

    This work focused on the evaluation of the recovery of organophosphorus pesticides from bee pollen after matrix solid phase-dispersion extraction (MSPD). Materials based on silica, titania and titania modified with polivylnylimidazole or polyestirene were used as adsorbents for the extraction of pesticides. Small amounts of fortified pollen (0.1 g, at 1 micro-g/g of pesticides), adsorbent (0.4 g) and solvent elution (1 mL de acetonitrile - ACN) were used in the extractions. For recovery evaluation, pollen extracts were analyzed by gas chromatography coupled with mass spectrometry.

  5. Determination of pesticide residues in fruit and vegetables.

    PubMed

    Torres, C M; Picó, Y; Mañes, J

    1996-11-22

    A review concerning the determination of pesticide residues in fruit and vegetables is presented. The basic principles and recent developments in the extraction and quantitation of pesticides are discussed. Consideration is given to solid phase and supercritical extraction techniques, automation and robotic systems, and immunoassay procedures.

  6. 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.

  7. 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

  8. 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

  9. Colorimetric and Phosphorimetric Dual-Signaling Strategy Mediated by Inner Filter Effect for Highly Sensitive Assay of Organophosphorus Pesticides.

    PubMed

    Zhang, Rong; Li, Na; Sun, Junyong; Gao, Feng

    2015-10-14

    We describe here a colorimetric and phosphorimetric dual-signaling strategy for sensitive assay of organophosphorus pesticides (OPPs). The principle for assay depends on the phenomenon that the phosphorescence of Mn-ZnS quantum dots (QDs) can be dramatically quenched by Au nanoparticles (AuNPs) through the inner filter effect (IFE) and the activity of acetylcholinesterase (AChE), an enzyme that catalytically hydrolyzes acetylthiocholine to thiocholine that can be inhibited by OPPs. By virtue of the variations of absorbance and phosphorescence of the analytical system, a dual-readout assay for OPPs has been proposed. The limits of detection for different OPPs including paraoxon, parathion, omethoate, and dimethyl dichlorovinyl phosphate (DDVP) are found to be 0.29, 0.59, 0.67, and 0.44 ng/L, respectively. The proposed assay was allowed to detect pesticides in real spiked samples and authentic contaminated apples with satisfactory results, suggesting its potential applications to detect pesticides in complicated samples.

  10. High-performance liquid chromatographic separation of the enantiomers of organophosphorus pesticides on polysaccharide chiral stationary phases.

    PubMed

    Ellington, J J; Evans, J J; Prickett, K B; Champion, W L

    2001-09-14

    High-performance liquid chromatographic separation of the individual enantiomers of 12 organophosphorus pesticides (OPs) was obtained on polysaccharide enantioselective HPLC columns using alkane-alcohol mobile phase. The OP pesticides were crotoxyphos, dialifor, fonofos, fenamiphos, fensulfothion, isofenphos, malathion, methamidophos, profenofos, crufomate, prothiophos and trichloronate. The enantiomers of fenamiphos, fensulfothion, profenofos and crufomate were separated on CHIRALPAK AD; the enantiomers of fenamiphos were also separated on CHIRALPAK AS; the enantiomers of methamidophos, crufomate and trichloronate were separated on CHIRALCEL OD; the enantiomers of crotoxyphos, dialifor, fonofos, malathion, prothiophos and trichloronate were separated on CHIRALCEL OJ; and the enantiomers of isofenphos were separated on CHIRALCEL OG. Baseline or partial separation of the enantiomers of six of these OP pesticides was obtained on CHIRALCEL OJ. In continued method development, the separation of the enantiomers of the 12 OPs was investigated more extensively on CHIRALCEL OJ to determine whether the mobile phase composition, flow-rate and column temperature could be optimized to yield at least partial separation of the enantiomers. Chromatographic conditions were found that gave either baseline or near baseline separations of the enantiomers of the 12 OPs on the CHIRALCEL OJ column. PMID:11587332

  11. Applied clinical pharmacology and public health in rural Asia – preventing deaths from organophosphorus pesticide and yellow oleander poisoning

    PubMed Central

    Eddleston, Michael

    2013-01-01

    Self-poisoning with pesticides or plants is a major clinical problem in rural Asia, killing several hundred thousand people every year. Over the last 17 years, our clinical toxicology and pharmacology group has carried out clinical studies in the North Central Province of Sri Lanka to improve treatment and reduce deaths. Studies have looked at the effectiveness of anti-digoxin Fab in cardiac glycoside plant poisoning, multiple dose activated charcoal in all poisoning, and pralidoxime in moderate toxicity organophosphorus insecticide poisoning. More recently, using a Haddon matrix as a guide, we have started conducting public health and animal studies to find strategies that may work outside of the hospital. Based on the 2009 GSK Research in Clinical Pharmacology prize lecture, this review shows the evolution of the group's research from a clinical pharmacology approach to one that studies possible interventions at multiple levels, including the patient, the community and government legislation. PMID:22943579

  12. 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....

  13. Biologic Monitoring to Characterize Organophosphorus Pesticide Exposure among Children and Workers: An Analysis of Recent Studies in Washington State

    PubMed Central

    Fenske, Richard A.; Lu, Chensheng; Curl, Cynthia L.; Shirai, Jeffry H.; Kissel, John C.

    2005-01-01

    We examined findings from five organophosphorus pesticide biomonitoring studies conducted in Washington State between 1994 and 1999. We compared urinary dimethylthiophosphate (DMTP) concentrations for all study groups and composite dimethyl alkylphosphate (DMAP) concentrations for selected groups. Children of pesticide applicators had substantially higher metabolite levels than did Seattle children and farmworker children (median DMTP, 25 μg/L; p < 0.0001). Metabolite levels of children living in agricultural communities were elevated during periods of crop spraying. Median DMTP concentrations for Seattle children and farmworker children did not differ significantly (6.1 and 5.8 μg/L DMTP, respectively; p = 0.73); however, the DMAP concentrations were higher for Seattle children than for farmworker children (117 and 87 nmol/L DMAP, respectively; p = 0.007). DMTP concentrations of U.S. children 6–11 years of age (1999–2000 National Health and Nutrition Examination Survey population) were higher than those of Seattle children and farmworker children at the 75th, 90th, and 95th percentiles. DMTP concentrations for workers actively engaged in apple thinning were 50 times higher than DMTP concentrations for farmworkers sampled outside of peak exposure periods. We conclude that workers who have direct contact with pesticides should continue to be the focus of public health interventions and that elevated child exposures in agricultural communities may occur during active crop-spraying periods and from living with a pesticide applicator. Timing of sample collection is critical for the proper interpretation of pesticide biomarkers excreted relatively soon after exposure. We surmise that differences in dietary exposure can explain the similar exposures observed among farmworker children, children living in the Seattle metropolitan area, and children sampled nationally. PMID:16263526

  14. 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

  15. Pesticide residues in grain from Kazakhstan and potential health risks associated with exposure to detected pesticides.

    PubMed

    Lozowicka, B; Kaczynski, P; Paritova, Capital A Cyrillic Е; Kuzembekova, G B; Abzhalieva, A B; Sarsembayeva, N B; Alihan, K

    2014-02-01

    This paper presents the first study of pesticide residue results in grain from Kazakhstan. A total of 80 samples: barley, oat, rye, and wheat were collected and tested in the accredited laboratory. Among 180 pesticides, 10 active substances were detected. Banned pesticides, such as DDTs, γ-HCH, aldrin and diazinon were found in cereal grain. Chlorpyrifos methyl and pirimiphos methyl were the most frequently detected residues. No residues were found in 77.5% of the samples, 13.75% contained pesticide residues at or below MRLs, and 8.75% above MRLs. The greatest percentage of samples with residues (29%) was noted for wheat, and the lowest for rye (20%). Obtained data were used to estimate potential health risks associated with exposure to these pesticides. The highest estimated daily intakes (EDIs) were as follows: 789% of the ADI for aldrin (wheat) and 49.8% of the ADI for pirimiphos methyl (wheat and rye). The acute risk from aldrin and tebuconazole in wheat was 315.9% and 98.7% ARfD, respectively. The results show that despite the highest EDIs of pesticide residues in cereals, the current situation could not be considered a serious public health problem. Nevertheless, an investigation into continuous monitoring of pesticide residues in grain is recommended.

  16. Dynamic microwave-assisted extraction online coupled with single drop microextraction of organophosphorus pesticides in tea samples.

    PubMed

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

    2015-08-14

    A new method for the determination of seven organophosphorus pesticides was developed using dynamic microwave-assisted extraction online coupled with single drop microextraction prior to gas chromatographic mass spectrometry (GC-MS). The method combines the advantages of dynamic microwave-assisted extraction and single-drop microextraction, which could greatly simplify the operation and reduce the whole pretreatment time. In the developed method, tea samples were extracted with 25% ethanol aqueous solution and purified with acidic alumina at the same time, and then the analytes were concentrated into microextraction solvent. When the extraction was completed, the solvent microdrop containing the enriched analytes was retracted into the microsyringe and directly analyzed by GC-MS without any filtration or cleanup step. The method makes extraction, cleanup, separation, and enrichment to be carried out in one step. Several experimental parameters, including type of extraction solvent, type and amount of dispersant, type and volume of microextraction solvent, microwave power, extraction time, and flow rate of extraction solvent were investigated and optimized. Under optimal experimental conditions, good linearity was observed in the range of 2.00-500.00 μg kg(-1). The limits of detection and quantification were in the range of 0.4-1.7 μg kg(-1) and 1.1-5.6 μg kg(-1), respectively. The present method was applied to the analysis of tea samples, and the recoveries of analytes were in the range of 84.9-106.4% with the relative standard deviations ranging from 1.0 to 6.1%. The results showed that the present method was a rapid and feasible method for the determination of organophosphorus pesticides in tea samples.

  17. Application of continual injection liquid-phase microextraction method coupled with liquid chromatography to the analysis of organophosphorus pesticides.

    PubMed

    Raharjo, Yanuardi; Sanagi, Mohd Marsin; Ibrahim, Wan Aini Wan; Naim, Ahmedy Abu; Aboul-Enein, Hassan Y

    2009-02-01

    A liquid-phase microextraction coupled with LC method has been developed for the determination of organophosphorus pesticides (methidation, quinalphos and profenofos) in drinking water samples. In this method, a small amount (3 microL) of isooctane as the acceptor phase was introduced continually to fill-up the channel of a 1.5 cm polypropylene hollow fiber using a microsyringe while the hollow fiber was immersed in an aqueous donor solution. A portion of the acceptor phase (ca. 0.4 microL) was first introduced into the hollow fiber and additional amounts (ca. 0.2 microL) of the acceptor phase were introduced to replenish at intervals of 3 min until set end of extraction (40 min). After extraction, the acceptor phase was withdrawn and transferred into a 2 mL vial for a drying step prior to injection into a LC system. Parameters that affect the extraction efficiency were studied including the organic solvent, length of fiber, volume of acceptor and donor phase, stirring rate, extraction time, and effect of salting out. The proposed method provided good enrichment factors of up to 189.50, with RSD ranging from 0.10 to 0.29%, analyte recoveries of over 79.80% and good linearity ranging from 10.0 to 1.25 mg/L. The LOD ranged from 2.86 to 82.66 microg/L. This method was applied successfully to the determination of organophosphorus pesticides in selected drinking water samples. PMID:19165835

  18. Pesticide residues in foods imported into the United States.

    PubMed

    Wessel, J R; Yess, N J

    1991-01-01

    Interest in pesticide residues in foods has increased, and the issue of residues in imported foods has been raised as a potential public health problem. Three U.S. government agencies, EPA, FDA, and USDA, are responsible for regulating pesticides. EPA sets tolerances, and FDA and USDA enforce those tolerances. As part of its regulatory activities, FDA conducts a regulatory monitoring program that samples and analyzes each year approximately 20,000 food shipments, about 60% of which are imports. Samples of imported foods are collected at ports of entry, and are chosen on the basis of several factors rather than on a completely random basis. Raw agricultural products are emphasized. Most analyses are performed using MRMs, to make best use of FDA's resources. Using five MRMs, about half of the 300 pesticides with U.S. tolerances can be determined. Results from monitoring over the past several years have shown that nearly 60% of the imported foods sampled had no pesticide residues detected. Of those samples that were violative, 5% contained residues for which there was no U.S. tolerance, and less than 1% had over-tolerance residues. Examples are given of the various pesticide/commodity combinations that have been found to be violative. FDA is often criticized for the scope of its pesticide coverage, particularly with regard to imported foods. Some critics have promoted the idea of a 'circle of poison,' which is based on the premise that pesticides banned in the U.S. are exported and used on foods in foreign countries; then the food containing these residues is imported into the U.S. and consumed. However, FDA's testing of imported foods has shown that residues of EPA-banned pesticides are not occurring from currently purposeful uses. The violation rates for imports also have not been significantly different from those for domestic foods. This indicates that foreign producers, as well as domestic growers, generally use pesticides in a manner consistent with EPA

  19. Development of a one-step microwave-assisted extraction method for simultaneous determination of organophosphorus pesticides and fungicides in soils by gas chromatography-mass spectrometry.

    PubMed

    Merdassa, Yared; Liu, Jing-fu; Megersa, Negussie

    2013-09-30

    A one-step microwave-assisted extraction (MAE) procedure was developed for the simultaneous extraction of organophosphorus pesticide and fungicide residues in soil which have been greatly used in agriculture. Parameters that could influence the MAE efficiency such as irradiation power, temperature, time and solvent were investigated, and extraction efficiencies in the range of 92.6-103.7% were obtained using 400 W (100% output) at 160 °C for 10 min with only 12 mL of acetone-hexane (2:1, v/v). The analytes in extracts were analyzed directly by gas chromatography-mass spectrometry (GC-MS) without any further cleanup. At 5 and 50 ng g(-1) fortification levels for each analyte, the average recoveries obtained were ranged from 70.0% to 120.0% with relative standard deviation (RSD) between 0.2% and 14%. The method was linear over 1-250 ng g(-1) with a correlation coefficient (r(2)) between 0.9916 and 0.9966. The detection limits (S/N=3) were between 0.10 and 0.12 ng g(-1). The applicability of the method was demonstrated by analyzing field soil samples collected from six intensive horticultural sites in Ethiopia.

  20. Pesticide residues in cereal crop grains in Poland in 2013.

    PubMed

    Malinowska, Elżbieta; Jankowski, Kazimierz; Sosnowski, Jacek; Wiśniewska-Kadżajan, Beata

    2015-06-01

    This paper presents the results of the audit on pesticide residues in cereal grains throughout Poland in 2013. The number of all samples of cereal grains was 380. Altogether 292 active substances of plant protection products were checked in the audit. Qualitative and quantative analyses were done according to Polish Standard PN-EN 15562:2008, using the LC-MS/MS technique. The methods (QuEChERS) is based on extraction of residues of plant protection products from a sample using acetonitrile. In the samples analyzed, 62 % of them did not contain any pesticide residues, 34 % of samples of cereal grains contained such residues but below the maximum residue limit, 3 % contained residues over the maximum limit, whereas 1 % of the samples contained illegal substances. The lowest amounts of pesticide residues were found in cereal grains coming from fields with cereal mixtures and in Avena grains, while the highest amounts were in Hordeum and Triticum grains. The substances found most often were fungicide residues. In northern and southern regions of Poland (Silesian, Pomeranian, and Kuyavian-Pomeranian voivodeships), cereal grains with pesticide residues were much more common than in other regions of Poland.

  1. 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...

  2. 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)...

  3. 40 CFR 158.2082 - Experimental use permit biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... pesticides residue data requirements table. 158.2082 Section 158.2082 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2082 Experimental use permit biochemical pesticides residue data requirements table. (a)...

  4. 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...

  5. 40 CFR 158.2040 - Biochemical 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 Biochemical pesticides residue data... (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2040 Biochemical pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to...

  6. 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)...

  7. 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

  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. Application of dispersive liquid-liquid microextraction for the analysis of organophosphorus pesticides in watermelon and cucumber.

    PubMed

    Zhao, Ercheng; Zhao, Wenting; Han, Lijun; Jiang, Shuren; Zhou, Zhiqiang

    2007-12-14

    In this article, a new method for the determination of organophosphorus pesticides (OPPs) in cucumber and watermelon was developed by using dispersive liquid-liquid microextraction (DLLME) and gas chromatography-flame photometric detection (GC-FPD). Acetonitrile (MeCN) was used as extraction solvent for the extraction of OPPs from plant samples. When the extraction process was finished, the target analytes in the extraction solvent were rapidly transferred from the MeCN extract to another small volume of organic solvent, chlorobenzene, using DLLME. Recovery tests were performed for concentrations between 0.5 and 20 microg/kg; recoveries for each target analyte were in the range between 67 and 111%. The repeatability of the proposed method, expressed as relative standard deviation, varied between 2 and 9% (n=3). Limits of detection of the method for watermelon and cucumber were found ranging from 0.010 to 0.190 microg/kg for all the target pesticides. Compared with the conventional sample preparation method, the proposed method has the advantage of being quick and easy to operate, and having high-enrichment factors and low consumption of organic solvent. PMID:18001747

  10. 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.

  11. An optical instrument to test pesticide residues in agricultural products

    NASA Astrophysics Data System (ADS)

    Qiu, Zhengjun; Zheng, Wenzhong; Fang, Hui; He, Yong

    2005-10-01

    Pesticide is one of the indispensability materials in modern agricultural management, however the excessive use of pesticides has threatened the ecological environment and people's health. This paper introduced an optical instrument to test the pesticide residues in agricultural products based on the inhibition rate of organophosphates against acrtyl-cholinesterase (AchE). The instrument consists mainly of a solid light source with 410nm wavelength, a sampling container, an optical sensor, a temperature sensor, and a MCU based data acquisition board. The light illuminated through the liquid in the sampling container, and the absorptivity was determined by the amount of the pesticide residues in the liquid. This paper involves the design of optical testing system, the data acquisition and calibration of the optical sensor, the design of microcontroller-based electrical board. Tests were done to reveal the affection of temperature and reacting time on AchE, to establish the relationship between the amount of methamidophos and dichlorvos with AchE. The results showed that the absorption rate was related to the pesticide residues and it could be concluded that the pesticide residues exceeded the normal level when the inhibition rate was over 50 percent. The instrument has potential application in vegetable markets.

  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. 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.,...

  14. 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...

  15. 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 ...

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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...

  1. 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.

  2. 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

  3. 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

  4. Ionic liquid-based vortex-assisted dispersive liquid-liquid microextraction of organophosphorus pesticides in apple and pear.

    PubMed

    Zhang, Lijin; Chen, Fang; Liu, Shaowen; Chen, Biyu; Pan, Canping

    2012-09-01

    An ionic liquid-based vortex-assisted dispersive liquid-liquid microextraction (DLLME) was developed for the analysis of trace amounts of six organophosphorus pesticides (OPPs) in apple and pear coupled with high-performance liquid chromatography. During the DLLME, the effect of some experimental factors including extraction solvent and its volume, dispersion solvent and its volume, vortex time, salt addition, and pH on the extraction procedure were investigated. Under the chosen extraction conditions, the analytes were enriched more than 300-fold and the limits of detections were greatly dropped to 0.061-0.73 μg/kg. The linearity relationship was observed in the range of 2-100 μg/kg with the correlation coefficients (R(2)) ranging from 0.9967 to 0.9983. The relative standard deviations varied from 2.3 to 5.7% (n = 6). Mean recovery values of the OPPs were in the range of 69.8-109.1% with a relative standard deviation lower than 7.0%. Based on these above, it could be concluded that 1-octyl-3-methylimidazolium hexafluorophosphate ([C(8)MIM][PF(6)]) was a good extraction solvent and the proposed [C(8)MIM][PF(6)]-based vortex-assisted DLLME method was suitable for the effective extraction of the OPPs in apple and pear.

  5. 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).

  6. Removal of residual pesticides in vegetables using ozone microbubbles.

    PubMed

    Ikeura, H; Kobayashi, F; Tamaki, M

    2011-02-15

    The removal of fenitrothion (FT) pesticide residues from vegetables by immersion in ozone-microbubbled solution was demonstrated. FT-treated lettuce, cherry tomatoes, and strawberries were immersed in ozone-microbubbled, ozone-millibubbled, and dechlorinated water. After that the percentage of residual FT in the vegetables was determined. Residual FT was efficiently removed from lettuce by immersing it in ozone-microbubbled solution containing more than 1.0 ppm dissolved ozone, or continuously generated ozone-microbubbled solution containing 2.0 ppm dissolved ozone. Similarly, for cherry tomatoes and strawberries, the continuously generated ozone-microbubbled solution containing 2.0 ppm dissolved ozone was highly effective. These results showed that ozone microbubbles effectively removed residual pesticides not only from leafy vegetables but also from fruity vegetables. PMID:21168959

  7. 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.

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

    USGS Publications Warehouse

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

    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.

  9. 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...

  10. 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...

  11. 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...

  12. Study on the effect of chain-length compatibility of mixed anionic-cationic surfactants on the cloud-point extraction of selected organophosphorus pesticides.

    PubMed

    Seebunrueng, Ketsarin; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

    2012-09-01

    The chain-length compatibility of mixed anionic-cationic surfactants was investigated for the extraction of organophosphorus pesticides (OPPs). Cationic surfactants with different chain lengths (n = 12 and 16) were mixed with sodium dodecyl sulfate (SDS; n = 12) for the mixed anionic-cationic surfactants-based extraction. Six OPPs were studied including azinphos-methyl, parathion-methyl, fenitrothion, diazinon, chlorpyrifos, and prothiophos. Reversed-phase high-performance liquid chromatography was used for the determination of the studied OPPs. The extraction was performed using mixtures of SDS and cationic surfactants including dodecyltrimethyl ammonium bromide or dodecyltrimethylammonium bromide (DTAB; n = 12) and cetyltrimethyl ammonium bromide or cetyltrimethyl ammonium bromide (CTAB; n = 16). The parameters affecting the extraction efficiencies of two extraction systems were studied and discussed. The optimum condition for SDS-DTAB was 15 mmol L(-1) SDS and 1 mmol L(-1) DTAB in the presence of 15% (w/v) sodium chloride (NaCl). Meanwhile, the condition for SDS-CTAB was 10 mmol L(-1) SDS and 1.0 mmol L(-1) CTAB with 10% (w/v) NaCl. Under the optimum conditions, the extraction efficiency of SDS-DTAB (66-85%) was slightly higher than that of SDS-CTAB (61-82%). In addition, the SDS-DTAB system also gave greater enrichment factor than SDS-CTAB for all the studied OPPs. This result may be due to the compatibility of chain length between SDS and DTAB. The extraction using SDS-DTAB was successfully applied to determine OPPs in fruit samples (i.e., pomelo, apple, and pineapple). No contamination by the studied OPPs in samples was observed. Good accuracy with recoveries ranging from 77 to 105% was obtained. Low limits of detection were in the range of 0.003-0.01 mg kg(-1) which are below the MRLs established by EU-MRLs for the OPPs residues in fruit samples.

  13. 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.,...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. Monitoring of some pesticides residues in different samples of meat and some organs of cattle.

    PubMed

    el-Aziz, T A

    1996-01-01

    Intensive use of pesticides for controlling pests in Egypt resulted in presence of minute amount of their residue in animal feeds and consequently in animal tissues. The present study aimed to monitor the residue of some commonly used pesticides in different samples of animal tissues obtained from rural areas. The results revealed high concentration of pesticides residue in liver and kidney. PMID:17217017

  20. 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

  1. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2011-06-01

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

  3. Integrating biotinylated polyalkylthiophene thin films with biological macromolecules: biosensing organophosphorus pesticides and metal ions with surface immobilized alkaline phosphatase utilizing chemiluminescence measurements

    NASA Astrophysics Data System (ADS)

    Pande, Rajiv; Kamtekar, S.; Ayyagari, Madhu S. R.; Marx, Kenneth A.; Kumar, Jayant; Tripathy, Sukant K.; Kaplan, David L.

    1995-05-01

    We describe a methodology for immobilizing the enzyme alkaline phosphatase onto a glass surface using a novel biotinylated copolymer poly (3-undecylthiophene-co-3- thiophenecarboxaldehyde) 6-biotinamido hexanohydrazide attached hydrophobically to silanized glass. The biotin-streptavidin protein interaction is used to carry out this immobilization. Alkaline phosphatase catalyzes the dephosphorylation of a class of macrocyclic compounds: including CSPD {chloro 3-[4-methoxy spiro(1,2 dioxetane-3-2-trichloro-(3.3.1.1)-decan]-4 yl}phenyl phosphate to a product species which emits energy by chemiluminescence. We can detect this chemiluminescence signal with a photomultiplier tube for both enzymatic catalysis in solution and the surface immobilized enzyme (streptavidin conjugate). This enzyme is inhibited by the organophosphorus class of pesticides as well as nerve agents. The enzyme is also inhibited by Be(II), Bi(III) as well as excess Zn(II), while the apoenzyme is reactivated by Zn(II). We demonstrate in this study that two representative organophosphorus pesticides inhibit the enzymatic production of chemiluminescent products. This is true for the enzyme conjugate both free in solution and immobilized. We can detect pesticides down to about 50 ppb for the enzyme in solution and 500 ppb for surface immobilized enzyme in a 100 (mu) l capillary. Detection of Zn(II) by apoenzyme reactivation occurs down to 3 ppb. Be(II) and Bi(III) are detected by inhibition down to 1 ppm.

  4. Ultrapreconcentration and determination of organophosphorus pesticides in water by solid-phase extraction combined with dispersive liquid-liquid microextraction and high-performance liquid chromatography.

    PubMed

    Chen, Junhua; Zhou, Guangming; Deng, Yongli; Cheng, Hongmei; Shen, Jie; Gao, Yi; Peng, Guilong

    2016-01-01

    Solid-phase extraction coupled with dispersive liquid-liquid microextraction was developed as an ultra-preconcentration method for the determination of four organophosphorus pesticides (isocarbophos, parathion-methyl, triazophos and fenitrothion) in water samples. The analytes considered in this study were rapidly extracted and concentrated from large volumes of aqueous solutions (100 mL) by solid-phase extraction coupled with dispersive liquid-liquid microextraction and then analyzed using high performance liquid chromatography. Experimental variables including type and volume of elution solvent, volume and flow rate of sample solution, salt concentration, type and volume of extraction solvent and sample solution pH were investigated for the solid-phase extraction coupled with dispersive liquid-liquid microextraction with these analytes, and the best results were obtained using methanol as eluent and ethylene chloride as extraction solvent. Under the optimal conditions, an exhaustive extraction for four analytes (recoveries >86.9%) and high enrichment factors were attained. The limits of detection were between 0.021 and 0.15 μg/L. The relative standard deviations for 0.5 μg/L of the pesticides in water were in the range of 1.9-6.8% (n = 5). The proposed strategy offered the advantages of simple operation, high enrichment factor and sensitivity and was successfully applied to the determination of four organophosphorus pesticides in water samples.

  5. Interrelation of Glycemic Status and Neuropsychiatric Disturbances in Farmers with Organophosphorus Pesticide Toxicity

    PubMed Central

    Jamal, Farrukh; Haque, Quazi S.; Singh, Sangram

    2016-01-01

    Background: Diverse group of agro-chemicals are indiscriminately sprayed by the farmers for pest control to enhance crop yield. About 25 million agricultural workers in the developing world suffer from at least one episode of poisoning each year, mainly by anticholinesterase- like organophosphates (OPs). Objective: The present study was aimed to establish the OP toxicity in 187 occupationally exposed pesticide sprayers of mango plantation in rural Malihabad, Lucknow, in terms of neuro-cognitive impairment, mental health status, clinical symptoms, diabetes, and hematological factors. Method: The exposed group was compared to 187 pesticides-unexposed normal healthy persons engaged in normal usual agricultural work (age, sex and education corresponding to age group of selected subject group) from Rural Malihabad, Lucknow (India). Neuro-cognitive impairment was measured using the Subjective Neurocognition Inventory and mental health status using the General Health questionnaire-28. The subjects were also tested for biochemical and enzymatic parameters. Results: The exposed farmers showed alterations in enzymatic and clinical parameters. While the rates of anxiety / insomnia and severe depression were also significantly higher in the pesticide sprayers, disorders affecting psychomotor speed, selective attention, divided attention, verbal memory, nonverbal memory, prospective memory, spatial functioning, and initiative/energy were all lower in the sprayers. Pesticide sprayers showed a number of clinical symptoms like eczema, saliva secretion, fatigue, headache, sweating, abdominal pain, nausea, superior distal muscle weakness, inferior distal muscle weakness, hand tingling and etc. which all significantly correlated with the number of working years. Conclusion: These findings suggested that farmers who work with OPs are prone to neuro-psychological disorders and diabetes. PMID:27688820

  6. Interrelation of Glycemic Status and Neuropsychiatric Disturbances in Farmers with Organophosphorus Pesticide Toxicity

    PubMed Central

    Jamal, Farrukh; Haque, Quazi S.; Singh, Sangram

    2016-01-01

    Background: Diverse group of agro-chemicals are indiscriminately sprayed by the farmers for pest control to enhance crop yield. About 25 million agricultural workers in the developing world suffer from at least one episode of poisoning each year, mainly by anticholinesterase- like organophosphates (OPs). Objective: The present study was aimed to establish the OP toxicity in 187 occupationally exposed pesticide sprayers of mango plantation in rural Malihabad, Lucknow, in terms of neuro-cognitive impairment, mental health status, clinical symptoms, diabetes, and hematological factors. Method: The exposed group was compared to 187 pesticides-unexposed normal healthy persons engaged in normal usual agricultural work (age, sex and education corresponding to age group of selected subject group) from Rural Malihabad, Lucknow (India). Neuro-cognitive impairment was measured using the Subjective Neurocognition Inventory and mental health status using the General Health questionnaire-28. The subjects were also tested for biochemical and enzymatic parameters. Results: The exposed farmers showed alterations in enzymatic and clinical parameters. While the rates of anxiety / insomnia and severe depression were also significantly higher in the pesticide sprayers, disorders affecting psychomotor speed, selective attention, divided attention, verbal memory, nonverbal memory, prospective memory, spatial functioning, and initiative/energy were all lower in the sprayers. Pesticide sprayers showed a number of clinical symptoms like eczema, saliva secretion, fatigue, headache, sweating, abdominal pain, nausea, superior distal muscle weakness, inferior distal muscle weakness, hand tingling and etc. which all significantly correlated with the number of working years. Conclusion: These findings suggested that farmers who work with OPs are prone to neuro-psychological disorders and diabetes.

  7. 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

  8. Enantiomeric separation of organophosphorus pesticides by high-performance liquid chromatography, gas chromatography and capillary electrophoresis and their applications to environmental fate and toxicity assays.

    PubMed

    Li, Ling; Zhou, Shanshan; Jin, Lixia; Zhang, Cheng; Liu, Weiping

    2010-05-15

    In recent years, the continuous evolution of the field of stereochemistry has produced a heightened awareness of the applications of pure enantiomers of agrochemicals. This review describes reports of the enantiomeric separation of commercial organophosphorus pesticides (OPs) and the applications of these methods to research on the enantioselectivity of the toxicity and environmental fate of these compounds. Chiral OPs can be analysed by high-performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrophoresis (CE). These different separation techniques for OP enantiomers are briefly discussed, and their applications are presented.

  9. Organochlorine pesticides residue in lakes of Khorezm, Uzbekistan

    USGS Publications Warehouse

    Rosen, Michael R.; Nishonov, Bakhriddin; Fayzieva, Dilorom; Saito, L.; Lamers, J.

    2009-01-01

    The Khorezm province in northwest Uzbekistan is a productive agricultural area within the Aral Sea Basin that produces cotton, rice and wheat. Various organochlorine pesticides were widely used for cotton production before Uzbekistan's independence in 1991. In Khorezm, small lakes have formed in natural depressions that receive inputs mostly from agricultural runoff. Samples from lake waters and sediments, as well as water from the Amu Darya River (which is the source of most of the lake water) have been analyzed to study variations in the concentrations of organochlorine pesticides residues during the year. Low concentrations of DDT, DDD, DDE, a-HCH and y-HCH compounds were found in water and sediment samples. The concentration of persistent organochlorine pesticides (DDT and HCH) in water and sediment is much lower than the maximum permissible concentrations that exist for water and soil. According to these preliminary results, the investigated lakes in Khorezm appear to be suitable for recreation or for aquaculture.

  10. 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.

  11. 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

  12. 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.

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

    PubMed

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

    2013-03-15

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

  14. 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

  15. 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

  16. 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

  17. The Organochlorine Pesticides Residue Levels in Karun River Water

    PubMed Central

    Behfar, Abdolazim; Nazari, Zahra; Rabiee, Mohammad Hassan; Raeesi, Gholamreza; Oveisi, Mohammad Reza; Sadeghi, Nafiseh; Jannat, Behrooz

    2013-01-01

    Background The organochlorine pesticides (OCPs) are among the most commonly used in water streams around the world. Most of these contaminants are highly hydrophobic and persist in sediments of rivers and lakes. Studies have suggested that OCPs may affect the normal function of the human and wildlife endocrine systems. Objectives The aim of this study is to determine the concentrations of selected organochlorine pesticides residues [OP'DDT, PP'DDT, alderin, dieldrin, heptachlor, (α,ß,γ,δ) HCH, (α, ß) endosulfan and metoxychlor] in samples from Karun River water at Khuzestan province in Iran , by GC-µ-ECD. Materials and Methods Water was extracted with n-hexane and then purified by passing through a glass column packed with Florisil and Na2SO4, which was then eluted with ether: hexane solution v/v. Results In general, all of 12 investigated organochlorine pesticides (OCPs) were detected. Regardless of the kind of OCPs, the highest OCP pollution level in Karun River were seen from August to November 2009 ranging 71.43 – 89.34 µg/L, and the lowest were seen from Dec 2010 to March 2011 at levels of 22.25 - 22.64 µg/L. The highest and lowest mean concentrations of 12 investigated pesticides were ß-Endosulfan and pp' DDT with 28.51and 0.01 µg/L respectively. Conclusions Comparison of total organochlorine pesticides residues concentration with WHO guidelines revealed that the Karun River had total OCPs residues above the probable effect level (0.2-20 µg/L, P < 0.05), which could pose a risk to aquatic life. PMID:24624185

  18. 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.

  19. Pesticide residues in fruits and vegetables in Ghana: a review.

    PubMed

    Donkor, Augustine; Osei-Fosu, Paul; Dubey, Brajesh; Kingsford-Adaboh, Robert; Ziwu, Cephas; Asante, Isaac

    2016-10-01

    Pesticides are known to improve agriculture yield considerably leading to an increase in its application over the years. The use of pesticides has shown varying detrimental effects in humans as well as the environment. Presently, enough evidence is available to suggest their misuse and overuse in the last few decades in most developing nations primarily due to lack of education, endangering the lives of farmers as well as the entire population and environment. However, there is paucity of data especially over long durations in Ghana resulting in the absence of effective monitoring programs regarding pesticide application and subsequent contamination in fruits and vegetables. Therefore, this review discusses comprehensively pesticide type and use, importation, presence in fruits and vegetables, human exposure, and poisoning in Ghana. This is to alert the scientific community in Ghana of the need to further research into the potential implications of pesticide residues in food commodities in order to generate a comprehensive and reliable database which is key in drafting policies simultaneous with food regulation, suitable monitoring initiatives, assessment, and education to minimize their effects thereon. PMID:27530198

  20. Pesticide residues in fruits and vegetables in Ghana: a review.

    PubMed

    Donkor, Augustine; Osei-Fosu, Paul; Dubey, Brajesh; Kingsford-Adaboh, Robert; Ziwu, Cephas; Asante, Isaac

    2016-10-01

    Pesticides are known to improve agriculture yield considerably leading to an increase in its application over the years. The use of pesticides has shown varying detrimental effects in humans as well as the environment. Presently, enough evidence is available to suggest their misuse and overuse in the last few decades in most developing nations primarily due to lack of education, endangering the lives of farmers as well as the entire population and environment. However, there is paucity of data especially over long durations in Ghana resulting in the absence of effective monitoring programs regarding pesticide application and subsequent contamination in fruits and vegetables. Therefore, this review discusses comprehensively pesticide type and use, importation, presence in fruits and vegetables, human exposure, and poisoning in Ghana. This is to alert the scientific community in Ghana of the need to further research into the potential implications of pesticide residues in food commodities in order to generate a comprehensive and reliable database which is key in drafting policies simultaneous with food regulation, suitable monitoring initiatives, assessment, and education to minimize their effects thereon.

  1. 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.

  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. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... HEXACHLOROBENZENE (HCB) 0.1 METHOXYCHLOR 0.1 TOXAPHENE 0.3 2,4-D (Temporary) 5.0 2,4,5-T 0.1 Sum of ALDRIN and DIELDRIN 0.1 Sum of CYPERMETHRIN and PERMETHRIN (Temporary) 3.0 Sum of DDT, TDE (DDD), and DDE 0.4 Sum of... 7 Agriculture 2 2012-01-01 2012-01-01 false Pesticide residue standards. 29.427 Section...

  4. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... HEXACHLOROBENZENE (HCB) 0.1 METHOXYCHLOR 0.1 TOXAPHENE 0.3 2,4-D (Temporary) 5.0 2,4,5-T 0.1 Sum of ALDRIN and DIELDRIN 0.1 Sum of CYPERMETHRIN and PERMETHRIN (Temporary) 3.0 Sum of DDT, TDE (DDD), and DDE 0.4 Sum of... 7 Agriculture 2 2013-01-01 2013-01-01 false Pesticide residue standards. 29.427 Section...

  5. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... HEXACHLOROBENZENE (HCB) 0.1 METHOXYCHLOR 0.1 TOXAPHENE 0.3 2,4-D (Temporary) 5.0 2,4,5-T 0.1 Sum of ALDRIN and DIELDRIN 0.1 Sum of CYPERMETHRIN and PERMETHRIN (Temporary) 3.0 Sum of DDT, TDE (DDD), and DDE 0.4 Sum of... 7 Agriculture 2 2014-01-01 2014-01-01 false Pesticide residue standards. 29.427 Section...

  6. 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.

  7. 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

  8. Design of a novel noninvasive spectrometer for pesticide residues monitor

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2014-11-01

    Although the gas or liquid chromatography had been widely used into pesticide residues monitoring, some drawbacks such as time-consuming, complicated operation and especially the destructivity for samples were existed. To overcome the limits of destructive detection methods, the noninvasive detection method based on spectroscopy was used to detect the pesticide residues in this paper. To overcome low resolution and light-efficiency due to the drawbacks of the classical plane and holography concave gratings, a novel noninvasive spectrometer for pesticide residues monitor (PRM) based on volume holography transmission (VHT) grating was designed. Meanwhile, a custom-built splitting light system for PRM based on the VHT grating was developed. In addition, the linear charge coupled device (CCD) with combined data acquisition (DAQ) card and the virtual-PRM based on LabVIEW were respectively used as the spectral acquisition hardware and software-platform. Experimental results showed that the spectral resolution of this spectrometer reached 2nm, and the VHT grating's diffraction efficiency was gotten via the simulation experiment.

  9. Use of Combined Uncertainty of Pesticide Residue Results for Testing Compliance with Maximum Residue Limits (MRLs).

    PubMed

    Farkas, Zsuzsa; Slate, Andrew; Whitaker, Thomas B; Suszter, Gabriella; Ambrus, Árpád

    2015-05-13

    The uncertainty of pesticide residue levels in crops due to sampling, estimated for 106 individual crops and 24 crop groups from residue data obtained from supervised trials, was adjusted with a factor of 1.3 to accommodate the larger variability of residues under normal field conditions. Further adjustment may be necessary in the case of mixed lots. The combined uncertainty of residue data including the contribution of sampling is used for calculation of an action limit, which should not be exceeded when compliance with maximum residue limits is certified as part of premarketing self-control programs. On the contrary, for testing compliance of marketed commodities the residues measured in composite samples should be greater than or equal to the decision limit calculated only from the combined uncertainty of the laboratory phase of the residue determination. The options of minimizing the combined uncertainty of measured residues are discussed. The principles described are also applicable to other chemical contaminants. PMID:25658668

  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. 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

  12. 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.

  13. Multiresidue determination of carbamate, organochlorine, organophosphorus, and dicarboximide pesticides in lettuce by GC/MS.

    PubMed

    Da Silva, Rogério Luiz; Da Silva, Claudia Pereira; Navickiene, Sandro

    2010-08-01

    An extraction method based on matrix solid-phase dispersion was developed to determine pirimicarb, methyl parathion, malathion, procymidone, alpha-endosulfan and beta-endosulfan in lettuce using gas chromatography-mass spectrometry. The best results were obtained using 4.0 g of lettuce, 2.0 g of silica as dispersant sorbent, 0.1 g of activated carbon as clean up sorbent and acetonitrile as eluting solvent. The method was validated using lettuce samples fortified with pesticides at six different concentration levels (0.1 to 2.0 mg/kg). Average recoveries (7 replicates) ranged from 50 to 120%, with relative standard deviations between 0.6 and 8.0%. Detection and quantification limits for lettuce ranged from 0.01 to 0.02 mg/kg and 0.04 to 0.10 mg/kg, respectively.

  14. 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.

  15. 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

  16. 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

  17. 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...

  18. 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.

  19. 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

  20. Determination of pesticide residues in animal origin baby foods by gas chromatography coupled with triple quadrupole mass spectrometry.

    PubMed

    Amendola, Graziella; Pelosi, Patrizia; Attard Barbini, Danilo

    2015-01-01

    A simple, fast and multiresidue method for the determination of pesticide residues in baby foods of animal origin has been developed in order to check the compliance with the Maximum Residue Levels (MRLs) set at a general value of 0.01 mg/kg by Commission Directive 2006/125/EC for infant foods. The main classes of organochlorine, organophosphorus and pyrethroid compounds have been considered, which are mainly fat soluble pesticides. The analytical procedure consists in the extraction of baby food samples by acetonitrile (ACN) followed by a clean up using C18 solid-phase extraction column eluted with ACN. The compounds were determined by gas chromatography-triple quadrupole mass spectrometry equipped with a Programmed Temperature Vaporizer (PTV) injection and a backflush system. In order to compensate for matrix effects PTV and matrix matched standard calibrations have been used. The method has been fully validated for 57 pesticides according to the Document SANCO/12571/2013. Accuracy and precision (repeatability) have been studied by recoveries at two spiking levels, the Limit of Quantitation (LOQ) (0.003-0.008 mg/kg) and 10 time greater (0.03-0.08 mg/kg), and the results were in the acceptable range of 70-120% with Relative Standards Deviations (RSD) ≤20%. Selectivity, linearity, LOQ and uncertainty of measurement were also determined for all the compounds. The method has been also applied for the analysis of 18 baby food animal origin samples, bought form the local market in Rome (Italy), and no pesticide in the scope of the method has been found above the MRL or the LOQ.

  1. 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

  2. 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.

  3. 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

  4. Spatio-temporal patterns of pesticide residues in the Turia and Júcar Rivers (Spain).

    PubMed

    Ccanccapa, Alexander; Masiá, Ana; Andreu, Vicente; Picó, Yolanda

    2016-01-01

    A study was conducted on the occurrence of 50 pesticides in water and sediments of Turia and Júcar Rivers (Valencian Community, Eastern Spain) for a period of two consecutive years each, 2010/2011 and 2012/2013, respectively to assess the contribution of agriculture and urban activities on pesticide pollution. The results showed that mean concentrations of pesticides ranged from pesticide whereas imazalil, thiabendazole, tolclofos methyl, ethion and carbofuran were those found at higher concentrations. Ubiquitous pesticides are those with long half-lives. The most polluted parts of the rivers were the headwaters and the mouth, which could be related to the agricultural practices and rainfall. Contrarily, in the abrupt part of the rivers of difficult access the contamination is low. Other quality parameters monitored in this study also corroborate the worst water quality in the alluvial plains that coincides with higher anthropic pressure. The temporal variations also indicated a strong relation of pesticide concentrations with hydrology, the higher the river flow, the higher number and frequency of pesticides but at lower concentrations. On the contrary, at lower river flows higher pesticide concentrations were detected. The risk assessment for aquatic biota pointed out that organophosphorus and fungicides are a threat to fish and daphnia and herbicides and fungicides are hazards for algae. Thus, the strict control of pesticide concentrations is important to preserve the aquatic ecosystems health.

  5. Spatio-temporal patterns of pesticide residues in the Turia and Júcar Rivers (Spain).

    PubMed

    Ccanccapa, Alexander; Masiá, Ana; Andreu, Vicente; Picó, Yolanda

    2016-01-01

    A study was conducted on the occurrence of 50 pesticides in water and sediments of Turia and Júcar Rivers (Valencian Community, Eastern Spain) for a period of two consecutive years each, 2010/2011 and 2012/2013, respectively to assess the contribution of agriculture and urban activities on pesticide pollution. The results showed that mean concentrations of pesticides ranged from pesticide whereas imazalil, thiabendazole, tolclofos methyl, ethion and carbofuran were those found at higher concentrations. Ubiquitous pesticides are those with long half-lives. The most polluted parts of the rivers were the headwaters and the mouth, which could be related to the agricultural practices and rainfall. Contrarily, in the abrupt part of the rivers of difficult access the contamination is low. Other quality parameters monitored in this study also corroborate the worst water quality in the alluvial plains that coincides with higher anthropic pressure. The temporal variations also indicated a strong relation of pesticide concentrations with hydrology, the higher the river flow, the higher number and frequency of pesticides but at lower concentrations. On the contrary, at lower river flows higher pesticide concentrations were detected. The risk assessment for aquatic biota pointed out that organophosphorus and fungicides are a threat to fish and daphnia and herbicides and fungicides are hazards for algae. Thus, the strict control of pesticide concentrations is important to preserve the aquatic ecosystems health. PMID:26118860

  6. Effects of stress pretreatment on the dynamics of blood cholinesterase activity after exposure to an organophosphorus pesticide in the rat.

    PubMed

    Gralewicz, Slawomir; Swiercz, Radoslaw; Lutz, Piotr; Wiaderna, Dorota; Wasowicz, Wojciech

    2010-01-01

    A single i.p. administration of 1.0 mg/kg of chlorphenvinphos (CVP), an organophosphorus pesticide, results in an acute stress response, evidenced by a marked (6-7 fold) rise in plasma corticosterone (CORT) concentration, and a diminished behavioural sensitivity to amphetamine (AMPH) three weeks postexposure. Surprisingly, in rats subjected to a single series of inescapable electric footshocks (60 10 msec triplets of 3.0 mA, 2 msec, square pulses during 20 min - IF ) two weeks prior to the CVP exposure, these effects are not observed. It has been assumed that the reduced effectiveness of CVP might be related to some persisting alterations in the functional state of the cholinergic system. The aim of the present work was to discover whether and in what way the IF pretreatment affects i) the cholinesterase activity in blood, and ii) the dynamics of the alterations in the cholinesterase (ChE) activity following the CVP exposure. The experiments were performed on 3 mo. old, male Wistar rats. In the first experiment, the blood samples were taken from the tail vein 15, 60 and 180 min after the IF. In the second experiment, the rats were pretreated with IF and 14 days later given 1.0 mg/kg of CVP i.p. Blood samples were taken 15 min, 60 min, 180 min, 24 h, 7 days, and 14 days after the CVP exposure. In the first experiment no differences in the ChE activity in plasma (pChE) and erythrocytes (rbcChE) were found between the shocked and control rats. In the second experiment, however, in rats pretreated with IF the rbcChE activity of was reduced by CVP less and pChE activity returned to normal faster than in rats not pretreated with IF. The results confirm that exposure to IF, a nonchemical stressor, induces some long-lasting adaptive changes which render the cholinergic system less susceptible to the harmful action of ChE inhibitors. It has been hypothesized that the changes consist in an increase of the antioxidant potential in blood and possibly other tissues. PMID

  7. 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

  8. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry data requirements and the substance to be tested for a... table shows the data requirements for microbial pesticides residue. The test notes are shown...

  9. 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....2172 Experimental use permit microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry...

  10. 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....2172 Experimental use permit microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry...

  11. 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....2172 Experimental use permit microbial pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry...

  12. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry data requirements and the substance to be tested for a... table shows the data requirements for microbial pesticides residue. The test notes are shown...

  13. 40 CFR 158.2130 - Microbial pesticides residue data requirements table.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... pesticides residue data requirements table. (a) General. Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry data requirements and the substance to be tested for a... table shows the data requirements for microbial pesticides residue. The test notes are shown...

  14. 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

    2016-03-01

    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.

  15. Acute organophosphorus poisoning.

    PubMed

    Chowdhary, Sheemona; Bhattacharyya, Rajasri; Banerjee, Dibyajyoti

    2014-04-20

    Acute organophosphorus poisoning continues to be a detrimental problem and a potential cause of mortality especially in developing countries. Inhibition of acetylcholinesterase enzyme is the main mechanism of toxicity of such pesticides and measurement of acetylcholinesterase activity is the commonly used laboratory diagnosis approved for the purpose. It is now proved beyond any doubt that early intervention is beneficial for cases of acute organophosphorus poisoning and, therefore, considerable current interest has been generated for development of point of care testing tool for screening of the same. However, to the best of our knowledge so far the matter is not reviewed from the view of point of care testing tool development. In this paper, this subject is reviewed highlighting the methodological aspects and point of care testing tool development in the context of organophosphorus poisoning.

  16. Quantitative 31P NMR for Simultaneous Trace Analysis of Organophosphorus Pesticides in Aqueous Media Using the Stir Bar Sorptive Extraction Method

    NASA Astrophysics Data System (ADS)

    Ansari, S.; Talebpour, Z.; Molaabasi, F.; Bijanzadeh, H. R.; Khazaeli, S.

    2016-09-01

    The analysis of pesticides in water samples is of primary concern for quality control laboratories due to the toxicity of these compounds and their associated public health risk. A novel analytical method based on stir bar sorptive extraction (SBSE), followed by 31P quantitative nuclear magnetic resonance (31P QNMR), has been developed for simultaneously monitoring and determining four organophosphorus pesticides (OPPs) in aqueous media. The effects of factors on the extraction efficiency of OPPs were investigated using a Draper-Lin small composite design. An optimal sample volume of 4.2 mL, extraction time of 96 min, extraction temperature of 42°C, and desorption time of 11 min were obtained. The results showed reasonable linearity ranges for all pesticides with correlation coefficients greater than 0.9920. The limit of quantification (LOQ) ranged from 0.1 to 2.60 mg/L, and the recoveries of spiked river water samples were from 82 to 94% with relative standard deviation (RSD) values less than 4%. The results show that this method is simple, selective, rapid, and can be applied to other sample matrices.

  17. 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

  18. 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.

  19. Development of an improved single-drop microextraction method and its application for the analysis of carbamate and organophosphorus pesticides in water samples.

    PubMed

    Wang, Xiuhong; Cheng, Jing; Wang, Xiangfang; Wu, Min; Cheng, Min

    2012-11-21

    An improved single-drop microextraction (SDME) method combined with high performance liquid chromatography has been developed for the detection of trace carbamate and organophosphorus pesticides in water samples. The most fascinating feature of the proposed method is the use of an oval-shaped polychloroprene rubber (PCR) tube to load the extraction solvent, which efficiently loads more solvent and improves the stability of extraction microdrop. Furthermore, this device provides a larger contact surface between the extraction solvent and the inner surface of the oval-shaped PCR tube than that between the extraction solvent and the tip of a microsyringe needle in the conventional SDME. It thereby avoids the problem of the drop floating upwards or dislodging from the tip of the microsyringe needle as observed in the traditional SDME. This method is significant for the great improvement it can offer in extraction efficiency. A series of extraction parameters were investigated systematically using carbamate and organophosphorus as the model analytes. Under the optimal conditions, the enrichment factors for analysis were between 117 and 177, and the limits of detection were ≦0.63 μg L(-1) (S/N = 3). The repeatability study was carried out by extracting the spiked water samples. Here the relative standard deviations varied between 4.0 and 5.8% (n = 5). Additionally, the proposed method was successfully applied to the determination of pesticides in real water samples, and good recoveries were obtained from 79% to 112%. The proposed method was demonstrated to hold advantages of low cost, simplicity of operation, and successful application to in real water samples.

  20. 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

  1. 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

  2. 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...

  3. 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.

  4. 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

  5. Solid phase microextraction of pesticide residues from strawberries.

    PubMed

    Hu, R; Hennion, B; Urruty, L; Montury, M

    1999-03-01

    A new solid phase microextraction method for the determination of pesticide residues in strawberries for 16 commonly used compounds was described. The strawberries were crushed and centrifuged. An aliquot of the well agitated aqueous supernatant (4 ml) was extracted with a fibre coated with polydimethylsiloxane (PDMS, 100 microns) for 45 min at room temperature. Identification and quantification were achieved using a gas chromatography-mass spectrometry (GC-MS) system and selective ion monitoring (SIM). The method was tested for the following pesticides: carbofuran, diethofencarb, penconazole, hexaconazole, metalaxyl, folpet, bromopropylate, dichlofluanid, alpha-endosulfan, beta-endosulfan, parathion ethyl, procymidone, iprodione, vinclozolin, myclobutanil and chlorothalonil. Limits of detection, repeatability and linearity for standard calibration in strawberries were obtained. Positive and negative effects of the matrix between the extracting solution of strawberries and water were observed. Stabilities of these compounds in the extracting solution of strawberries were determined. The solvent-free SPME procedure was found to be quicker and more cost effective than the solvent extraction methods commonly used.

  6. 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.

  7. Application of statistical design of experiment with desirability function for the removal of organophosphorus pesticide from aqueous solution by low-cost material.

    PubMed

    Islam, M Azharul; Sakkas, Vasilios; Albanis, Triantafyllos A

    2009-10-15

    This paper deals with the multiple response optimization for the removal of organophosphorus pesticide quinalphos [QP: O,O-diethyl O-2-quinoxalinyl phosphorothioate] from the aqueous solution onto low-cost material and tried to overcome the drawbacks of univariate optimization. Used tea leaves were used as low-cost adsorbent and batch equilibration method was followed for this study. A Box-Behnken design was used to develop response model and desirability function was then used for simultaneous optimization of all affecting parameters in order to achieve the highest removal% of quinalphos. The optimum conditions of factors predicted for quinalphos removal% were found to be: pH 8.83, concentration 7 mg L(-1) and dose 0.40 g. Under these conditions, maximum removal% of quinalphos was obtained 96.31%. Considering the above optimum conditions, the adsorption isotherms were developed and provided adsorption capacity of 196.07 microg g(-1) by using Langmuir equation, indicating that used tea leaves may be applied as a low-cost material for pesticides removal from aqueous matrices.

  8. 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

  9. 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.

  10. Review of analytical methods for the determination of pesticide residues in grapes.

    PubMed

    Grimalt, Susana; Dehouck, Pieter

    2016-02-12

    This review presents an overview of analytical methods for the analysis of pesticide residues in grapes and by-products in the last decade. The most widely used detection technique for the determination of pesticides in grapes is mass spectrometry combined with gas and/or liquid chromatography. In general, multi-residue methods with selective sample treatment methodologies have been developed for this purpose. However, this review focuses not only on these common multi-residue methods but also on specific methodologies as single-residue methods for the analysis of pesticides in grapes and by-products. Finally, the limitations of multi-residue methods, the future perspectives and the trends for pesticide residue analysis in grapes are reviewed.

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Cumulative risk assessment of pesticide residues in food.

    PubMed

    Boobis, Alan R; Ossendorp, Bernadette C; Banasiak, Ursula; Hamey, Paul Y; Sebestyen, Istvan; Moretto, Angelo

    2008-08-15

    There is increasing need to address the potential risks of combined exposures to multiple residues from pesticides in the diet. The available evidence suggests that the main concern is from dose addition of those compounds that act by the same mode of action. The possibility of synergy needs to be addressed on a case-by-case basis, where there is a biologically plausible hypothesis that it may occur at the levels of residues occurring in the diet. Cumulative risk assessment is a resource-intense activity and hence a tiered approach to both toxicological evaluation and intake estimation is recommended, and the European Food Safety Authority (EFSA) has recently published such a proposal. Where assessments have already been undertaken by some other authority, full advantage should be taken of these, subject of course to considerations of quality and relevance. Inclusion of compounds in a cumulative assessment group (CAG) should be based on defined criteria, which allow for refinement in a tiered approach. These criteria should include chemical structure, mechanism of pesticidal action, target organ and toxic mode of action. A number of methods are available for cumulating toxicity. These are all inter-related, but some are mathematically more complex than others. The most useful methods, in increasing levels of complexity and refinement, are the hazard index, the reference point index, the Relative Potency Factor method and physiologically based toxicokinetic modelling, although this last method would only be considered should a highly refined assessment be necessary. Four possible exposure scenarios are of relevance for cumulative risk assessment, acute and chronic exposure in the context of maximum residue level (MRL)-setting, and in relation to exposures from the actual use patterns, respectively. Each can be addressed either deterministically or probabilistically. Strategies for dealing with residues below the limit of detection, limit of quantification or limit

  17. 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 ...

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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...

  3. Occurrence of pesticide residues and transformation products in different types of dietary supplements.

    PubMed

    Páleníková, Agneša; Martínez-Domínguez, Gerardo; Arrebola, Francisco Javier; Romero-González, Roberto; Hrouzková, Svetlana; Garrido Frenich, Antonia

    2015-01-01

    The purpose of this study was to evaluate the presence of pesticide residues and transformation products in dietary supplement products. Thirty-two samples were analysed to determine 177 pesticides by gas chromatography-tandem mass spectrometry (GC-MS/MS) and 333 pesticides by liquid chromatography-high-resolution mass spectrometry (LC-HRMS). Pesticides were extracted from different kinds of dietary supplements by the use of a modified QuEChERS extraction method. Six samples contained pesticide residues at concentration up to 92.7 µg kg(-1), but only butralin exceeded the maximum residue limits set for raw material. In addition to target compounds, LC-HRMS enables the simultaneous detection of non-target pesticides. In this case, transformation products of pesticides were detected in the analysed samples using HRMS analyser (Exactive-Orbitrap). These compounds were not included in the original method, and they were monitored as post-target compounds, knowing their molecular formula and exact mass. Mass accuracy was always < 2 ppm, corresponding to a maximum mass error. The positive findings endorse the idea that a deeper and continuous investigation of pesticide residues and transformation products in dietary supplement products is necessary in order to guaranty consumer's safety.

  4. 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... COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.429 Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of...

  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... COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.429 Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of...

  6. 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... COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.429 Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of...

  7. 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... COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.429 Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of...

  8. 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... COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Regulations Miscellaneous § 29.429 Disposition of imported tobacco exceeding pesticide residue standards. Within 10 days of the receipt of...

  9. 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...

  10. 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

  11. 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...

  12. Status and effect of pesticide residues in soils under different land uses of Andaman Islands, India.

    PubMed

    Murugan, A V; Swarnam, T P; Gnanasambandan, S

    2013-10-01

    Pesticides are shown to have a great effect on soil organisms, but the effect varies with pesticide group and concentration, and is modified by soil organic carbon content and soil texture. In the humid tropical islands of Andaman, India, no systematic study was carried out on pesticide residues in soils of different land uses. The present study used the modified QuEChERS method for multiresidue extraction from soils and detection with a gas chromatograph. DDT and its various metabolites, α-endosulfan, β-endosulfan, endosulfan sulfate, aldrin, and fenvalerate, were detected from the study area. Among the different pesticide groups detected, endosulfan and DDT accounted for 41.7 % each followed by aldrin (16.7 %) and synthetic pyrethroid (8.3 %). A significantly higher concentration of pesticide residues was detected in rice-vegetable grown in the valley followed by rice-fallow and vegetable-fallow in the coastal plains. Soil microbial biomass carbon is negatively correlated with the total pesticide residues in soils, and it varied from 181.2 to 350.6 mg kg(-1). Pesticide residues have adversely affected the soil microbial populations, more significantly the bacterial population. The Azotobacter population has decreased to the extent of 51.8 % while actinomycetes were the least affected though accounted for 32 % when compared to the soils with no residue.

  13. [Quantitative Analysis of Dimethoate Pesticide Residues in Honey by Surface-Enhanced Raman Spectroscopy].

    PubMed

    Sun, Xu-dong; Dong, Xiao-ling

    2015-06-01

    The feasibility of a combination method of surface-enhanced Raman spectroscopy (SERS) technology and linear regression algorithm was investigated for rapid quantitative analysis of pesticide residues in honey. The total of 30 samples was applied in the experiment with dimethoate pesticide residues range from 1 ppm to 10 ppm. The samples were divided into calibration set (20) and prediction set (10). The substrate of Klarite with an inverted pyramidal structure was adopted for improvement of the relative intensity of the majority of Raman shift peaks. The comparative analysis was carried out between SERS spectra of dimethoate pesticide residues in honey samples and conventional Raman spectra of dimethoate standard sample. And four characteristic Raman shift peaks at the wavenumbers of 867, 1 065, 1 317 and 1 453 cm(-1) were found, which were related with the vibrational information of dimethoate molecule. The relationship was developed by linear regression algorithm between the intensity of Raman shift and the concentration of dimethoate pesticide residues. The 10 new samples in the prediction set were applied to evaluate the performance of the models. By comparison, the optimal model was obtained with the characteristic Raman shift peak of 867 cm(-1). The higher correlation coefficient of prediction of 0.984 and lower root mean square error of prediction of 0.663 ppm were obtained. The detection limit of this method was 2 ppm, which was close to the maximum levels of pesticide residue detection limits. Experimental results showed that it was feasible to rapidly analyze quantitative of pesticide residues in honey with the combination method of SERS technology and linear regression algorithm. Compared with the conventional method coupled with the suitable pretreatment, the combination method of SERS technology and linear regression method could analyze the dimethoate pesticide residues in honey, and it also provided an optional method for rapid quantitative analysis

  14. 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...

  15. 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...

  16. 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...

  17. Occurrence of pesticide residues in Lebanon's water resources.

    PubMed

    Kouzayha, Abir; Al Ashi, Aisha; Al Akoum, Rami; Al Iskandarani, Mohamad; Budzinski, Hélène; Jaber, Farouk

    2013-11-01

    Contamination of water sources by pesticides is one of the most critical environmental problems. The present work is designed to address the occurrence of 67 pesticides in the Lebanese waters. Chemical analysis was performed by a solid-phase extraction followed by a gas chromatography-mass spectrometry using programmed temperature vaporization injection. In drinking water and groundwater samples, organochlorine and organophosphate pesticides were frequently detected with a maximal sum concentration of up to 31.8 ng L(-1). High pesticide ecotoxicological risk was noticed in many surface waters, while this risk was driven mainly by diazinon, chlorpyrifos, fenpropathrin and bifenthrin insecticides.

  18. Acetylcholinesterase biosensor based on a gold nanoparticle-polypyrrole-reduced graphene oxide nanocomposite modified electrode for the amperometric detection of organophosphorus pesticides.

    PubMed

    Yang, Yuqi; Asiri, Abdullah Mohamed; Du, Dan; Lin, Yuehe

    2014-06-21

    A nanohybrid of gold nanoparticles, polypyrrole, and reduced graphene oxide sheets (named as Au-PPy-rGO) was achieved by electrochemical deposition of reduced graphene oxide with pyrrole and the introduction of gold nanoparticles. Acetylcholinesterase (AChE) was further encapsulated in a silica matrix and immobilized on the Au-PPy-rGO nanocomposite by co-deposition with (NH4)2SiF6. The presence of PPy helped to avoid the aggregation of rGO caused by van der Waals interactions between individual sheets and significantly increased the surface area of the modified electrode. The obtained Au-PPy-rGO nanocomposite not only showed excellent conductivity but also exhibited a high electrocatalytic activity and specific affinity for thiocholine, the hydrolysis product of the enzyme, and thus an improved detection sensitivity. Since AChE molecules were protected by the circumambient silica matrix, which provided a biocompatible environment and facilitated mass transport, the fabricated AChE biosensor displayed high stability and excellent activity together with a fast response to organophosphorus pesticides. Under optimum conditions, the biosensor led to the rapid and sensitive detection of paraoxon-ethyl from 1.0 nM to 5 μM with a detection limit of 0.5 nM.

  19. Fenthion, an organophosphorus pesticide, induces alterations in oxidant/antioxidant status and histopathological disorders in cerebrum and cerebellum of suckling rats.

    PubMed

    Ben Amara, Ibtissem; Sefi, Mediha; Troudi, Afef; Soudani, Nejla; Boudawara, Tahia; Zeghal, Najiba

    2014-08-01

    Fenthion (FEN) is an organophosphorus pesticide known for its wide toxic manifestations. In this study, the effects of FEN were evaluated on the cerebrum and cerebellum oxidant/antioxidant status and histopathological disorders in the suckling rats. Pregnant rats were divided into two groups: control group received pure water, while FEN group received daily by their drinking water 551 ppm of FEN from the 14th day of pregnancy until day 14 after delivery. Acetylcholine esterase (AChE) activity was inhibited in both the cerebrum and cerebellum of suckling rats whose mothers were treated with FEN. The cerebrum and cerebellum oxidative damage was demonstrated by a significant increase of malondialdehyde (MDA), advanced oxidation protein product and glutathione (GSH) levels and disturbance in the antioxidant enzyme activities. A significant decline of non-protein thiol and vitamin C levels was also observed. These changes were confirmed by histopathological observations which were marked by pyknotic neurons in the cerebrum and apoptotic cells in the cerebellum of FEN-treated rats. In the cerebellum of FEN-treated rats, the most conspicuous damage was the absence of external granular layer, indicating growth retardation. These data suggested that exposure of pregnant and lactating rats to FEN induced oxidative stress and histopathological disorders in the cerebrum and cerebellum of their pups. Thus, the use of FEN must be under strict control, especially for pregnant and lactating mothers.

  20. 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.

  1. Chemometric assisted ultrasound leaching-solid phase extraction followed by dispersive-solidification liquid-liquid microextraction for determination of organophosphorus pesticides in soil samples.

    PubMed

    Ahmadi, Kamyar; Abdollahzadeh, Yaser; Asadollahzadeh, Mehdi; Hemmati, Alireza; Tavakoli, Hamed; Torkaman, Rezvan

    2015-05-01

    Ultrasound leaching-solid phase extraction (USL-SPE) followed by dispersive-solidification liquid-liquid microextraction (DSLLME) was developed for preconcentration and determination of organophosphorus pesticides (OPPs) in soil samples prior gas chromatography-mass spectrometry analysis. At first, OPPs were ultrasonically leached from soil samples by using methanol. After centrifugation, the separated methanol was diluted to 50 mL with double-distillated water and passed through the C18 SPE cartridge. OPPs were eluted with 1 mL acetonitrile. Thus, 1 mL acetonitrile extract (disperser solvent) and 10 µL 1-undecanol (extraction solvent) were added to 5 mL double-distilled water and a DSLLME technique was applied. The variables of interest in the USL-SPE-DSLLME method were optimized with the aid of chemometric approaches. First, in screening experiments, fractional factorial design (FFD) was used for selecting the variables which significantly affected the extraction procedure. Afterwards, the significant variables were optimized using response surface methodology (RSM) based on central composite design (CCD). Under the optimum conditions, the enrichment factors were 6890-8830. The linear range was 0.025-625 ng g(-1) and limits of detection (LODs) were between 0.012 and 0.2 ng g(-1). The relative standard deviations (RSDs) were in the range of 4.06-8.9% (n=6). The relative recoveries of OPPs from different soil samples were 85-98%.

  2. 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

  3. 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.

  4. 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

  5. Ascorbic acid surface modified TiO₂-thin layers as a fully integrated analysis system for visual simultaneous detection of organophosphorus pesticides.

    PubMed

    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 PO₄(3-) in 25.0 min. Based on the chromogenic reaction between PO₄(3-) 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. PMID:25319460

  6. Sol-gel polydimethylsiloxane/poly(vinylalcohol)-coated stir bar sorptive extraction of organophosphorus pesticides in honey and their determination by large volume injection GC.

    PubMed

    Yu, Chunhe; Hu, Bin

    2009-01-01

    A PDMS/poly(vinylalcohol) (PDMS/PVA) film prepared through a sol-gel process was coated on stir bars for sorptive extraction, followed by liquid desorption and large volume injection-GC-flame photometric detector (LVI-GC-FPD) for the determination of five organophosphorus pesticides (OPPs) (phorate, fenitrothion, malathion, parathion, and quinalphos) in honey. The preparation reproducibility of PDMS/PVA-coated stir bar ranged from 4.3 to 13.4% (n = 4) in one batch, and from 6.0 to 12.6% (n = 4) in batch to batch. And one prepared stir bar can be used for more than 50 times without apparent coating loss. The significant parameters affecting stir bar sorptive extraction (SBSE) were investigated and optimized. The LODs for five OPPs ranged from 0.013 (parathion) to 0.081 microg/L (phorate) with the RSDs ranging from 5.3 to 14.2% (c = 1 microg/L, n = 6). The proposed method was successfully applied to the analysis of five OPPs in honey. PMID:19035384

  7. Ascorbic acid surface modified TiO₂-thin layers as a fully integrated analysis system for visual simultaneous detection of organophosphorus pesticides.

    PubMed

    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 PO₄(3-) in 25.0 min. Based on the chromogenic reaction between PO₄(3-) 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.

  8. 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%.

  9. Fluorescence Resonance Energy Transfer-based Biosensor Composed of Nitrogen-doped Carbon Dots and Gold Nanoparticles for the Highly Sensitive Detection of Organophosphorus Pesticides.

    PubMed

    Gong, Nian Chun; Li, Yan Le; Jiang, Xi; Zheng, Xiao Fang; Wang, Ya Ya; Huan, Shuang Yan

    2016-01-01

    The present article reports a novel biosensor for organophosphorus pesticides based on fluorescence resonance energy transfer (FRET) between nitrogen-doped carbon dots (NC-dots) and gold nanoparticles (AuNPs). The effective NC-dots/AuNPs assembly through the Au-N interaction results in good fluorescence quenching. Active acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylthiocholine into -SH containing thiocholine to replace the NC-dots and trigger the aggregation of AuNPs. In the presence of paraoxon, the activity of AChE is inhibited, and thus preventing the generation of thiocholine, causing fewer NC-dots to be replaced. As a consequence, the fluorescence intensity gradually decreases with increasing amount of paraoxon. This biosensor does not require any complex synthesis or modification, and the results show a wide detection range of from 10(-4) to 10(-9) g/L with a detection limit of 1.0 × 10(-9) g/L (3.6 × 10(-12) mol/L). Two linear response regions have been reported with a turning point at about 10(-6) g/L and three different factors that would influence the response behavior. These phenomena discussed in detail so as to explain the special response mechanism. PMID:27682399

  10. On-line trace-level enrichment gas chromatography of triazine herbicides, organophosphorus pesticides, and organosulfur compounds from drinking and surface waters.

    PubMed

    Pico, Y; Louter, A J; Vreuls, J J; Brinkman, U A

    1994-09-01

    A simple, selective and precise procedure for the analysis of water samples by on-line solid phase extraction gas chromatography (SPE-GC) is presented. The determination of several triazines, organophosphorus pesticides, sulfur containing compounds in tap water was performed by SPE-GC using polymer-packed precolumns and flame ionization (FID), nitrogen-phosphorus (NPD) or flame photometric (FPD) detection. A cartridge packed with silica was inserted between the precolumn and the gas chromatograph in order to eliminate trace amounts of water present in the ethyl acetate used as desorption solvent. Incorporation of a drying step allowed the retention gap to be used for the analysis of ca. 100 samples without significant deterioration of the chromatographic peaks. Analyte recovery was at least 72% when 10 ml of tap-water sample were analysed. The detection limits for all analytes in tap water were lower than 0.1 microgram l-1, with all detectors used. Although with NPD and FPD, selectivity and sensitivity were markedly better. The SPE-GC-NPD system has also been used for the analysis of surface-water samples from different European rivers. PMID:7978329

  11. Physicochemical and biological data for the development of predictive organophosphorus pesticide QSARs and PBPK/PD models for human risk assessment.

    PubMed

    Knaak, James B; Dary, Curt C; Power, Fred; Thompson, Carol B; Blancato, Jerry N

    2004-01-01

    A search of the scientific literature was carried out for physiochemical and biological data [i.e., IC50, LD50, Kp (cm/h) for percutaneous absorption, skin/water and tissue/blood partition coefficients, inhibition ki values, and metabolic parameters such as Vmax and Km] on 31 organophosphorus pesticides (OPs) to support the development of predictive quantitative structure-activity relationship (QSAR) and physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) models for human risk assessment. Except for work on parathion, chlorpyrifos, and isofenphos, very few modeling data were found on the 31 OPs of interest. The available percutaneous absorption, partition coefficients and metabolic parameters were insufficient in number to develop predictive QSAR models. Metabolic kinetic parameters (Vmax, Km) varied according to enzyme source and the manner in which the enzymes were characterized. The metabolic activity of microsomes should be based on the kinetic activity of purified or cDNA-expressed cytochrome P450s (CYPs) and the specific content of each active CYP in tissue microsomes. Similar requirements are needed to assess the activity of tissue A- and B-esterases metabolizing OPs. A limited amount of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CaE) inhibition and recovery data were found in the literature on the 31 OPs. A program is needed to require the development of physicochemical and biological data to support risk assessment methodologies involving QSAR and PBPK/PD models.

  12. Vortex-assisted low density solvent based demulsified dispersive liquid-liquid microextraction and high-performance liquid chromatography for the determination of organophosphorus pesticides in water samples.

    PubMed

    Seebunrueng, Ketsarin; Santaladchaiyakit, Yanawath; Srijaranai, Supalax

    2014-05-01

    A simple, rapid, effective and eco-friendly preconcentration method, vortex-assisted low density solvent based solvent demulsified dispersive liquid-liquid microextraction (VLDS-SD-DLLME), followed by high performance liquid chromatography-diode array detector (HPLC-DAD) analysis, has been developed for the first time for the determination of four organophosphorus pesticides (OPPs) (e.g., azinphos-methyl, parathion-methyl, fenitrothion and diazinon) in environmental water samples. In this preconcentration procedure, an emulsion was obtained after the mixture of extraction solvent (1-dodecanol) and dispersive solvent (acetonitrile, ACN) was injected rapidly into 10 mL of the sample solution. The vortex agitator aided the dispersion of the extraction solvent into the sample solution. After the formation of an emulsion, the demulsifier (ACN) was added, resulting in the rapid separation of the mixture into two phases without centrifugation. Under optimal conditions, the proposed method provided high extraction efficiency (90-99%), good linearity range (0.5-500 ng mL(-1)), low limits of detection (0.25-1 ng mL(-1)) and good repeatability and recoveries were obtained.

  13. 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

  14. 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

  15. 77 FR 63782 - Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on a Commodity

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-17

    ... chemicals in or on the food commodity, wheat, grain. DATES: Comments must be received on or before November... chemicals in or on the food commodity, wheat, grain. The Agency is taking public comment on the request... modification of regulations for residues of pesticides in or on the food commodity, wheat, grain....

  16. Aqueous acetonitrile extraction for pesticide residue analysis in agricultural products with HPLC-DAD.

    PubMed

    Watanabe, Eiki; Kobara, Yuso; Baba, Koji; Eun, Heesoo

    2014-07-01

    To reduce hazardous organic solvent consumption during sample preparation procedures as much as possible, an extraction method of smallest feasible sample volume (5g) using aqueous acetonitrile (MeCN) was developed to extract pesticide residues from agricultural samples prior to HPLC-DAD determination. Extraction with MeCN/water (1:1, v/v), and adjustment of the MeCN concentration by diluting with water after extraction recovered successfully most pesticides showing various physicochemical properties. The matrix effects of tested samples on the proposed method developed herein were generally negligibly-small. The average recoveries were in the range 70-120% for all pesticides with the coefficient of variation values below 20%. The reduction rate of organic solvents used for the proposed sample preparation method was up to approximately 60% compared with the Japanese authorised official method for pesticide residue analyses. These results demonstrate the feasibility of the proposed method for pesticides with diverse properties.

  17. Impact assessment of pesticide residues in fish of Ganga river around Kolkata in West Bengal.

    PubMed

    Aktar, Md Wasim; Paramasivam, M; Sengupta, Daipayan; Purkait, Swarnali; Ganguly, Madhumita; Banerjee, S

    2009-10-01

    An investigation was conducted from 2001 to 2005 for determining the residual concentration of five pesticides, viz., total-HCH, total-DDT, total-Endosulfan, Dimethoate and Malathion in fish samples collected from various points of the river Ganga. Fish samples were analyzed for pesticide residues using standard laboratory procedures by GC method. It was found that total-HCH concentration remains above the MRL values for maximum number of times in comparison to four other pesticides. The pesticide contamination to fish may be due to indiscriminate discharge of polluted and untreated sewage-sludge to the river. The pesticide contents in some places are alarming. Thus proper care, maintenance, treatment and disposal of sewage water and sludge are most vital and should be the prime thrust for the nation.

  18. Impact assessment of pesticide residues in fish of Ganga river around Kolkata in West Bengal.

    PubMed

    Aktar, Md Wasim; Paramasivam, M; Sengupta, Daipayan; Purkait, Swarnali; Ganguly, Madhumita; Banerjee, S

    2009-10-01

    An investigation was conducted from 2001 to 2005 for determining the residual concentration of five pesticides, viz., total-HCH, total-DDT, total-Endosulfan, Dimethoate and Malathion in fish samples collected from various points of the river Ganga. Fish samples were analyzed for pesticide residues using standard laboratory procedures by GC method. It was found that total-HCH concentration remains above the MRL values for maximum number of times in comparison to four other pesticides. The pesticide contamination to fish may be due to indiscriminate discharge of polluted and untreated sewage-sludge to the river. The pesticide contents in some places are alarming. Thus proper care, maintenance, treatment and disposal of sewage water and sludge are most vital and should be the prime thrust for the nation. PMID:18758975

  19. [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

  20. A novel device based on a fluorescent cross-responsive sensor array for detecting pesticide residue

    NASA Astrophysics Data System (ADS)

    Huang, Jing; Hou, Changjun; Lei, Jincan; Huo, Danqun; Luo, Xiaogang; Dong, Liang

    2016-11-01

    In this paper, a novel, simple, rapid, and low-cost detection device for pesticide residue was constructed. A sensor array based on a cross-responsive mechanism was designed. The data collection and processing system was used to detect fluorescent signal of the sensor arrays, and to extract unique patterns of the tested pesticide residue. Four selected pesticides, carbendazim, diazine, fenvalerate, and pentachloronitrobenzene, were detected by the proposed device. Unsupervised pattern recognition methods, hierarchical cluster analysis and principal component analysis, were used to analyze the data. The results showed that the methods could 100% discriminate the four pesticide residues. According to the standard regression linear curve of the fluorescence intensity and the concentration of pesticide, the quantitative value of the pesticide was detected, and the device obtained responses at concentrations below 8 ppb, and it has a good linear relationship in the range of 0.01-1 ppm. According to the results, the proposed detection device showed excellent selectivity and discrimination ability for the pesticide residues. However, our preliminary study demonstrated that the proposed detection device has excellent potential application for the safety inspection of food.

  1. 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.

  2. 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.

  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.

  4. 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

  5. Residue analysis of multi-class pesticides in watermelon by LC-MS/MS.

    PubMed

    Park, Semin; Lee, Sung Joong; Kim, Hae Gyeong; Jeong, Won Young; Shim, Jae-Han; Abd El-Aty, A M; Jeong, Sung Woo; Lee, Won Sup; Kim, Soo Taek; Shin, Sung Chul

    2010-03-01

    As watermelon is farmed primarily by protected and successive cultivation techniques, a number of pesticides are required for the control of pests and diseases. To evaluate the harmful effects of pesticides in watermelon and to guarantee consumers' safety, a rapid screening process for pesticides is required. A LC-MS/MS method was applied for the direct quantitation of 44 pesticide residues in watermelon. A Zorbax XDB-C(18) column was selected for analysis, with a mobile phase consisting of a gradient system of water and 5 mM methanolic ammonium formate. MS/MS experiments were performed in ESI positive ion and multiple reaction monitoring modes. The LOQs were in the range of 1-26 microg/kg, thereby indicating good sensitivity. Most of the recoveries ranged between 70-131% with RSDs < or = 20%. We suggested that the amount of pesticide residues such as pyroquilon (pyn), boscalid (bd), and dimethomorph (di) in amides (AM) and cinosulfuron (ci) in ureas (UR) may have been overestimated for the pesticides owing to increased alpha-error risk, whereas the amounts of pesticide residues, such as imibenconazole (ie) in the triazoles (TR) and fenpyroximate (fee) in the imidazoles (IM), may have been underestimated as the result of increased beta-error risk. The current method allowed for the rapid quantitation and identification of low pesticide levels in the watermelon samples. No pesticide residues were detected in any of the surveyed watermelons obtained from eight local markets in the Republic of Korea. Statistical analysis of the recoveries classified the 44 pesticides into nine groups and three overall categories. PMID:20175086

  6. Determination of organophosphorus pesticides and metabolites in cereal-based baby foods and wheat flour by means of ultrasound-assisted extraction and hollow-fiber liquid-phase microextraction prior to gas chromatography with nitrogen phosphorus detection.

    PubMed

    González-Curbelo, Miguel Ángel; Hernández-Borges, Javier; Borges-Miquel, Teresa María; Rodríguez-Delgado, Miguel Ángel

    2013-10-25

    A new method based on hollow-fiber liquid-phase microextraction (HF-LPME) has been developed for the determination of a group of organophosphorus pesticides, including some of their metabolites, in two commercial cereal-based baby foods and one wheat flour prior to gas chromatography-nitrogen phosphorus detection. Samples were first extracted by ultrasound-assisted extraction with acetonitrile (ACN) containing 1.25% (v/v) of formic acid. After evaporation and reconstitution in Milli-Q water, the HF-LPME procedure, using 1-octanol as extraction solvent, was applied followed by a desorption step in ACN, which clearly improved the performance of the technique. The effects of sample pH, ionic strength, stirring rate, extraction temperature and time as well as the desorption procedure were investigated. Under the optimum conditions that involved the extraction of the analytes from 10 mL of the water reconstituted extract at pH 7.0 containing 5% (w/v) of NaCl for 45 min at 960 rpm, the method was validated in terms of linearity, precision and accuracy. The limits of detection (LODs) were between 0.29 and 3.20 μg/kg. The extraction of Milli-Q water, as an example of the applicability of the procedure to aqueous samples, allowed achieving LODs in the range 0.01-0.04 μg/L. Such values, together with the ones achieved for the rest of the samples, are below or equal to the maximum residue limits specified by the European Union. PMID:23809845

  7. 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.

  8. Pesticide residues in ground water of the San Joaquin Valley, California

    USGS Publications Warehouse

    Domagalski, J.L.; Dubrovsky, N.M.

    1992-01-01

    A regional assessment of non-point-source contamination of pesticide residues in ground water was made of the San Joaquin Valley, an intensively farmed and irrigated structural trough in central California. About 10% of the total pesticide use in the USA is in the San Joaquin Valley. Pesticides detected include atrazine, bromacil, 2.4-DP, diazinon, dibromochloropropane, 1,2-dibromoethane, dicamba, 1,2-dichloropropane, diuron, prometon, prometryn, propazine and simazine. All are soil applied except diazinon. Pesticide leaching is dependent on use patterns, soil texture, total organic carbon in soil, pesticide half-life and depth to water table. Leaching is enhanced by flood-irrigation methods except where the pesticide is foliar applied such as diazinon. Soils in the western San Joaquin Valley are fine grained and are derived primarily from marine shales of the Coast Ranges. Although shallow ground water is present, the fewest number of pesticides were detected in this region. The fine-grained soil inhibits pesticide leaching because of either low vertical permeability or high surface area; both enhance adsorption on to solid phases. Soils of the valley floor tend to be fine grained and have low vertical permeability. Soils in the eastern part of the valley are coarse grained with low total organic carbon and are derived from Sierra Nevada granites. Most pesticide leaching is in these alluvial soils, particularly in areas where depth to ground water is less than 30m. The areas currently most susceptible to pesticide leaching are eastern Fresno and Tulare Counties. Tritium in water molecules is an indicator of aquifer recharge with water of recent origin. Pesticide residues transported as dissolved species were not detected in non-tritiated water. Although pesticides were not detected in all samples containing high tritium, these samples are indicative of the presence of recharge water that interacted with agricultural soils. ?? 1992.

  9. 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.

  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. 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

  13. 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

  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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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

  20. Paper-based fluorescent sensor for rapid naked-eye detection of acetylcholinesterase activity and organophosphorus pesticides with high sensitivity and selectivity.

    PubMed

    Chang, Jiafu; Li, Haiyin; Hou, Ting; Li, Feng

    2016-12-15

    Various strategies have been proposed for the sensing of acetylcholinesterase (AChE) activity and organophosphorus pesticides (OPs). However, the practical application of most methods is restricted by their intrinsic drawbacks such as complexity, long analysis time, and high cost. Thus, it is highly desirable to develop simple, fast and sensitive approaches for AChE activity and OPs detection. Herein, we reported a simple paper-based fluorescent sensor (PFS) based on the aggregation induced emission (AIE) effect of tetraphenylethylene (TPE) and the addition reaction capability of maleimide, which has been used as a powerful tool for rapid naked-eye detection of AChE activity and OPs. The introduction of TPE provides the probe with unique fluorescence property in solid state and is of great importance for improving the sensitivity of PFS. The hydrolysis product of acetylthiocholine catalyzed by AChE induced the maleimide ring destruction and activated the fluorescence performance of TPE. Given that AChE activity can be specifically inhibited by OPs, the as-proposed PFS can also be utilized for sensitive detection of OPs. Meanwhile, the variation of fluorescence signal can be readily detected by naked eyes, and low detection limits of 2.5mUmL(-1) and 0.5ngmL(-1) for AChE activity and OPs are obtained, respectively. Moreover, it has been successfully applied for AChE activity and OPs detection in diluted human serum samples, showing its great potential to be applied in real samples. Thus, this strategy possesses considerable advantages of simplicity, rapid detection, portability, cost efficiency and visualization. PMID:27498323

  1. 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.

  2. 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.

    PubMed

    Chen, Aiqiong; Du, Dan; Lin, Yuehe

    2012-02-01

    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 (MWCNTs-Au) nanocomposites modified screen printed carbon electrode (SPCE), which is used for the immobilization of AChE specific antibody. 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 concentrations of paraoxon were used to validate the new AChE assay method. AChE inhibition in OP dosed solutions was proportional to OP 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 exposure to OPs.

  3. Paper-based fluorescent sensor for rapid naked-eye detection of acetylcholinesterase activity and organophosphorus pesticides with high sensitivity and selectivity.

    PubMed

    Chang, Jiafu; Li, Haiyin; Hou, Ting; Li, Feng

    2016-12-15

    Various strategies have been proposed for the sensing of acetylcholinesterase (AChE) activity and organophosphorus pesticides (OPs). However, the practical application of most methods is restricted by their intrinsic drawbacks such as complexity, long analysis time, and high cost. Thus, it is highly desirable to develop simple, fast and sensitive approaches for AChE activity and OPs detection. Herein, we reported a simple paper-based fluorescent sensor (PFS) based on the aggregation induced emission (AIE) effect of tetraphenylethylene (TPE) and the addition reaction capability of maleimide, which has been used as a powerful tool for rapid naked-eye detection of AChE activity and OPs. The introduction of TPE provides the probe with unique fluorescence property in solid state and is of great importance for improving the sensitivity of PFS. The hydrolysis product of acetylthiocholine catalyzed by AChE induced the maleimide ring destruction and activated the fluorescence performance of TPE. Given that AChE activity can be specifically inhibited by OPs, the as-proposed PFS can also be utilized for sensitive detection of OPs. Meanwhile, the variation of fluorescence signal can be readily detected by naked eyes, and low detection limits of 2.5mUmL(-1) and 0.5ngmL(-1) for AChE activity and OPs are obtained, respectively. Moreover, it has been successfully applied for AChE activity and OPs detection in diluted human serum samples, showing its great potential to be applied in real samples. Thus, this strategy possesses considerable advantages of simplicity, rapid detection, portability, cost efficiency and visualization.

  4. 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

  5. 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

  6. A comprehensive evaluation of the efficacy of leading oxime therapies in guinea pigs exposed to organophosphorus chemical warfare agents or pesticides.

    PubMed

    Wilhelm, Christina M; Snider, Thomas H; Babin, Michael C; Jett, David A; Platoff, Gennady E; Yeung, David T

    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 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 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.

  7. A simple solvothermal process for fabrication of a metal-organic framework with an iron oxide enclosure for the determination of organophosphorus pesticides in biological samples.

    PubMed

    Zhang, Suling; Jiao, Zhe; Yao, Weixuan

    2014-12-01

    An active magnetic metal-organic framework (MOF) hybrid material was prepared using a novel in situ solvothermal method in the presence of magnetite (Fe3O4) particles, that holds much promise for large-scale synthesis. MIL-101(Fe), an iron terephthalate with pore structure and high resistance to water and common solvents, was functionalized as a model with superparamagnetic qualities, using Fe3O4. The electrostatic interaction between Fe3O4 and metal ions was thereby used to chemically stabilize magnetic nanoparticles, and thus MOF crystals were uniformly enclosed by Fe3O4 to form a homogeneous magnetic product identified as a Fe3O4/MIL-101 composite. This hybrid material with magnetic susceptibility but with the lowest possible loading amount of Fe3O4 was examined, and its potential application for magnetic solid-phase extraction of six organophosphorus pesticides (OPPs) from human hair and urine samples, followed by gas chromatography analysis, was assessed. The main effect parameters including solution ionic strength, desorption solvent, extraction time and desorption time were investigated in sequence. Under optimized conditions, this method showed low detection limits (0.21-2.28 ng/mL), wide linearity, and good precision (1.8-8.7% for intra-day, 2.9-9.4% for inter-day). The matrix interference produced by hair or urine could be effectively eliminated using this method, and satisfactory recoveries of the spiked samples were 76.8-94.5% and 74.9-92.1%, respectively, indicating that the Fe3O4/MIL-101 sorbents are feasible for the analysis of trace analytes from biological samples.

  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. 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.

  10. 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

  11. 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.

  12. 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

  13. Organochlorine pesticides residues in bottled drinking water from Mexico City.

    PubMed

    Díaz, Gilberto; Ortiz, Rutilio; Schettino, Beatriz; Vega, Salvador; Gutiérrez, Rey

    2009-06-01

    This work describes concentrations of organochlorine pesticides in bottled drinking water (BDW) in Mexico City. The results of 36 samples (1.5 and 19 L presentations, 18 samples, respectively) showed the presence of seven pesticides (HCH isomers, heptachlor, aldrin, and p,p'-DDE) in bottled water compared with the drinking water standards set by NOM-127-SSA1-1994, EPA, and World Health Organization. The concentrations of the majority of organochlorine pesticides were within drinking water standards (0.01 ng/mL) except for beta-HCH of BW 3, 5, and 6 samples with values of 0.121, 0.136, and 0.192 ng/mL, respectively. It is important monitoring drinking bottled water for protecting human health.

  14. 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

  15. 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.

  16. "Keep a low profile": pesticide residue, additives, and freon use in Australian tobacco manufacturing

    PubMed Central

    Chapman, S

    2003-01-01

    Objectives: To review the Australian tobacco industry's knowledge of pesticide residue on Australian tobacco and its policies and practices on resisting calls by tobacco control advocates that consumers should be informed about pesticide residue as well as additives. Methods: Review of previously internal industry documents relevant to pesticides and additives in Australian tobacco located from the Master Settlement Agreement websites. Results: Between 1972 and 1994 Philip Morris Australia was aware that its leaf samples were often contaminated with pesticide residue, sometimes including organochlorine levels described by PM's European laboratories as being "extremely high". Consumers were not advised of the contamination nor products withdrawn. From 1981, the industry also resisted calls to declare fully the extent of use and long term safety data on all additives used in their products. They developed standard public responses that were evasive and misleading and, in 2000, implemented voluntary additive disclosure which allowed the companies to continue to avoid disclosure of any ingredient they deemed to be a trade secret. There was extensive use of ozone depleting freon in Australian tobacco manufacturing. Again, the industry kept this information away from consumers. Conclusions: Australian smokers are unable to make informed decisions about smoking because pesticide and additive disclosure remains voluntary. The Australian government should regulate tobacco to require full disclosure including information on the likely health consequences of inhaling pesticide and additive pyrolysis products. PMID:14645948

  17. 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

  18. 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

  19. 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

  20. Assessment of pesticide residues in strawberries grown under various treatment regimes.

    PubMed

    Kovacova, Jana; Hrbek, Vojtech; Kloutvorova, Jana; Kocourek, Vladimir; Drabova, Lucie; Hajslova, Jana

    2013-01-01

    The dynamics of pesticide residues in strawberries that involved quantification of pesticide residues in ripe fruits after model treatment was evaluated in repeated field trials conducted over 3 years. Sixteen commercial pesticide formulations in various combinations were employed in applications from 7 to 44 days before harvest. Altogether 21 active ingredients and some of their metabolites were determined in treated strawberries using LC-MS and GC-MS methods. Except for propargite, the concentrations of all active ingredients declined below the respective MRLs (Regulation (EC) No. 396/2005); nevertheless, most of the tested fungicides often persisted above the 0.01 mg kg⁻¹ limit required by baby food producers to avoid the risk of exceeding the 'baby food limit' established in Commission Directive 2006/141/EC. On the other hand, residues of the majority of tested insecticides, namely spinosad, pymetrozine, deltamethrin, lambda-cyhalothrin and azadirachtin, declined below this limit. PMID:24303788

  1. 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.

  2. 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.

  3. 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

  4. Effects of food processing on pesticide residues in fruits and vegetables: a meta-analysis approach.

    PubMed

    Keikotlhaile, B M; Spanoghe, P; Steurbaut, W

    2010-01-01

    Pesticides are widely used in food production to increase food security despite the fact that they can have negative health effects on consumers. Pesticide residues have been found in various fruits and vegetables; both raw and processed. One of the most common routes of pesticide exposure in consumers is via food consumption. Most foods are consumed after passing through various culinary and processing treatments. A few literature reviews have indicated the general trend of reduction or concentration of pesticide residues by certain methods of food processing for a particular active ingredient. However, no review has focused on combining the obtained results from different studies on different active ingredients with differences in experimental designs, analysts and analysis equipment. In this paper, we present a meta-analysis of response ratios as a possible method of combining and quantifying effects of food processing on pesticide residue levels. Reduction of residue levels was indicated by blanching, boiling, canning, frying, juicing, peeling and washing of fruits and vegetables with an average response ratio ranging from 0.10 to 0.82. Baking, boiling, canning and juicing indicated both reduction and increases for the 95% and 99.5% confidence intervals.

  5. 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

  6. Meta-analysis of food processing on pesticide residues in fruits.

    PubMed

    Liang, Y; Liu, Y; Ding, Y; Liu, X J

    2014-01-01

    The combining and quantifying effects of food processing on pesticide residues in fruits were analysed by a meta-analysis approach. Data were collected from many publications and used to calculate response ratios, confidence intervals and intra-assay coefficients of variation. The response ratios for washing by tap water, boiling and sun drying were 0.59, 0.71 and 0.65, respectively, indicating that they could reduce the pesticide residues effectively. Peeling and juicing, where response ratios were 0.11 and 0.14, respectively, showed they could reduce the pesticide residues to a very small extent. An increase of pesticide residues was indicated by oven drying with a response ratio of more than 1. Oven drying and sun drying indicated both a reduction and an increase at the 99.5% confidence interval. The response ratios given by a meta-analysis approach could be used as processing factors in food safety risk assessment and as a guide for consumers on how to reduce pesticides effectively in fruit.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. Residues of five pesticides in field-treated alfalfa seeds and alfalfa sprouts.

    PubMed

    Archer, T E; Gauer, W O

    1985-08-01

    Residues of five different pesticides applied to alfalfa seed crops were determined in the harvested seeds and in sprouts grown from these seeds. Although seeds are usually used for future production of alfalfa plants, some of these seeds may be sprouted for human food consumption. The pesticides studied--aldicarb (Temik), chlorothalonil (Bravo), chlorpyrifos (Lorsban), methamidophos (Monitor) and propargite (Comite)--were applied at a normal usage rate and at two to three times that rate. Residues on the seeds and sprouts, if any, were insignificant at rates of application.

  12. 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

  13. 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

  14. 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.

  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.

  16. 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.

  17. 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

  18. Efficiency of wipe sampling on hard surfaces for pesticides and PCB residues in dust.

    PubMed

    Cettier, Joane; Bayle, Marie-Laure; Béranger, Rémi; Billoir, Elise; Nuckols, John R; Combourieu, Bruno; Fervers, Béatrice

    2015-02-01

    Pesticides and polychlorinated biphenyls (PCBs) are commonly found in house dust and have been described as a valuable matrix to assess indoor pesticide and PCB contamination. The aim of this study was to assess the efficiency and precision of cellulose wipe for collecting 48 pesticides, eight PCBs, and one synergist at environmental concentrations. First, the efficiency and repeatability of wipe collection were determined for pesticide and PCB residues that were directly spiked onto three types of household floors (tile, laminate, and hardwood). Second, synthetic dust was used to assess the capacity of the wipe to collect dust. Third, we assessed the efficiency and repeatability of wipe collection of pesticides and PCB residues that was spiked onto synthetic dust and then applied to tile. In the first experiment, the overall collection efficiency was highest on tile (38%) and laminate (40%) compared to hardwood (34%), p<0.001. The second experiment confirmed that cellulose wipes can efficiently collect dust (82% collection efficiency). The third experiment showed that the overall collection efficiency was higher in the presence of dust (72% vs. 38% without dust, p<0.001). Furthermore, the mean repeatability also improved when compounds were spiked onto dust (<30% for the majority of compounds). To our knowledge, this is the first study to assess the efficiency of wipes as a sampling method using a large number of compounds at environmental concentrations and synthetic dust. Cellulose wipes appear to be efficient to sample the pesticides and PCBs that adsorb onto dust on smooth and hard surfaces.

  19. Monitoring survey of the use patterns and pesticide residues on vegetables in the Niayes zone, Senegal.

    PubMed

    Diop, Amadou; Diop, Yérim M; Thiaré, Diène D; Cazier, Fabrice; Sarr, Serigne O; Kasprowiak, Amaury; Landy, David; Delattre, François

    2016-02-01

    The main objective of this work was to determine the impact of pesticide use practices on vegetables contamination in the Niayes zone of Dakar. A preliminary survey involving 200 farmers, showed the application of pesticides belonging to different groups on vegetable crops. Use practices in terms of application intervals and methods, measuring tools and dosage were not in compliance with good agricultural practices. In view of survey results, investigations on vegetable contamination were conducted. Therefore, 175 vegetable samples including cabbage (31 samples), lettuce (88 samples), tomato (57 samples) collected from four sites of the Niayes zone during four campaigns, were analyzed for residues of 21 pesticides, eighteen of which (18) were cited to be used by farmers. The results indicated that 65% of tomato samples, 71% of lettuce and 93% of cabbage contained one or more detectable residues. Among the monitored pesticides dicofol, chlorpyrifos, DDTs, dimethoate, and λ-cyhalothrin were the most predominant, found in at least 35% of samples for each vegetable. The frequencies of pesticide detection were, generally in agreement with the citation frequencies. The results provided important information on vegetable contamination status and pointed an urgent need to control pesticide use.

  20. Monitoring survey of the use patterns and pesticide residues on vegetables in the Niayes zone, Senegal.

    PubMed

    Diop, Amadou; Diop, Yérim M; Thiaré, Diène D; Cazier, Fabrice; Sarr, Serigne O; Kasprowiak, Amaury; Landy, David; Delattre, François

    2016-02-01

    The main objective of this work was to determine the impact of pesticide use practices on vegetables contamination in the Niayes zone of Dakar. A preliminary survey involving 200 farmers, showed the application of pesticides belonging to different groups on vegetable crops. Use practices in terms of application intervals and methods, measuring tools and dosage were not in compliance with good agricultural practices. In view of survey results, investigations on vegetable contamination were conducted. Therefore, 175 vegetable samples including cabbage (31 samples), lettuce (88 samples), tomato (57 samples) collected from four sites of the Niayes zone during four campaigns, were analyzed for residues of 21 pesticides, eighteen of which (18) were cited to be used by farmers. The results indicated that 65% of tomato samples, 71% of lettuce and 93% of cabbage contained one or more detectable residues. Among the monitored pesticides dicofol, chlorpyrifos, DDTs, dimethoate, and λ-cyhalothrin were the most predominant, found in at least 35% of samples for each vegetable. The frequencies of pesticide detection were, generally in agreement with the citation frequencies. The results provided important information on vegetable contamination status and pointed an urgent need to control pesticide use. PMID:26519803

  1. 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... TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7 Petitions... foods. (a) Petitions to be filed with the Agency under the provisions of FFDCA section 408(d) shall...

  2. 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... petition relates to a tolerance for a processed food, reports of investigations conducted using the... TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Procedural Regulations § 180.7...

  3. 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.

  4. 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

  5. [Determination of 132 pesticide residues in tobacco by gas chromatography-tandem mass spectrometry].

    PubMed

    Chen, Xiaoshui; Bian, Zhaoyang; Tang, Gangling; Hu, Qingyuan

    2012-10-01

    A simple method for the determination of 132 pesticide residues in tobacco by gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS) was established. The influences of different extraction solvents, different buffer systems and different purifying agents on the recoveries of pesticides were investigated. The tobacco sample was extracted with acetonitrile, then cleaned up by the mixed sorbents of primary secondary amine (PSA) and octadecylsilane (C18E). After dried by nitrogen, the extract residue was reconstituted with n-hexane-acetone (9:1, v/v). GC-MS/MS in multi-reaction monitoring (MRM) mode was used as the detection method and triphenyl phosphate (TPP) as the internal standard. All of the 132 pesticides had good linear relationships (r2 > 0.99) between 20 microg/kg and 2 000 microg/kg. At the three spiked levels of 50, 200 and 500 microg/kg in the tobacco extract, the average recoveries of all the pesticides were in the range of 68.10% to 123.15% except for mirex and hexachlorobenzene; moreover, the relative standard deviations (RSDs) of them were between 1.79% and 19.88%. We participated in the CORESTA (Cooperation Centre for Scientific Research Relative to Tobacco) 2012's co-experiment. The results of our method and the existed standard methods had good consistency. The accurate, reliable and sensitive method can be applied to the determination of the 132 pesticide residues in tobacco for rapid screening and quantitative analysis.

  6. [Occurrence of some pesticides residues in peppermint Mentha piperita L. in 2003-2005].

    PubMed

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

    2006-01-01

    The aim of this paper was to present occurrence of pesticides residues in peppermint Mentha Piperita in 2003-2005 and to estimate of their intakes by consumer. Gas chromatographic and spectroscopy methods were used. The most frequently found were chlorpyrifos residues (16% analysed samples) followed by terbacil (11%), dithiocarbamates (10%) and diazinon (5%). Residues in 14% analysed samples exceeded the European Union Maximum Residue Levels established for tea. Assuming consumption of peppermint on the level of 4.5 g (three bags) per day, short-term intake by adult and child consumer was a few times lower then Acceptable Daily Intake.

  7. 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.

  8. Organochlorine pesticide residues in a farming area, Nova Scotia--1972-73.

    PubMed

    Burns, B G; Peach, M E; Stiles, D A

    1975-06-01

    Soil, silt, and water samples from the Habitant Creek water-shed, Nova Scotia, a tobacco-growing area, have been monitored for organochlorine insecticides. Most samples contain measurable quantities of many persistent pesticides used in farming during the past decade. Sediment levels indicate that residues settle in sluggish parts of the stream. Drainage ditches show highest residual content caused in part by mass transport of soil in runoff. Residue content of water samples is normally one-tenth to one-hundredth that of silt, but is much higher during periods of heavy runoff. Levels vary with the seasons and are highest in the fall, decrease through the spring and summer, and are lowest in the winter. Although samples of well water taken fairly close to the stream showed virtually no residual content, a natural drainage reservior had a pesticide content similar to that in the stream.

  9. 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.

  10. Pesticides and trace metals residue in grape and home made wine in Jordan.

    PubMed

    Al Nasir, F; Jiries, A G; Batarseh, M I; Beese, F

    2001-02-01

    Sixty home made wine and sixty-four grape samples were collected from five territories in Jordan, where grapes and wine are mostly producted. The collected samples were analyzed for the most used organochlorine pesticides (OCP) and organophosphorous pesticides (OPP) in Jordan, as well as for four heavy metals (Ni, Cu, Zn and Pb). The results showed that OCPs residues were detected in 73% of the wine samples but no OPPs residue were detected which is due to generally shorter half life of the later pesticide. Grapes showed higher incident of contamination than wine, however, OCPs and OPPs with both short and long half-lives were detected. The OPPs were detected in only 8.3% of the analyzed grape samples. Heavy metals showed higher values in grapes than in the wine samples and it was attributed to removal of solids during wine preparation processes or through contamination of wine during storage. Most of the samples were below toxic limit.

  11. 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.

  12. 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

  13. 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.

  14. 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...

  15. 40 CFR 158.2040 - Biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... pesticide may be applied directly to water, unless it can be demonstrated that the treated water would not... aquatic nonfood use if there is direct application to water that could subsequently result in exposure to... the Residue 860.1400 Potable water NR CR NR NR TGAI 1, 12 860.1400 Fish NR CR NR NR TGAI 1, 13...

  16. 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

  17. Uncertainty of the sample size reduction step in pesticide residue analysis of large-sized crops.

    PubMed

    Omeroglu, P Yolci; Ambrus, Á; Boyacioglu, D; Majzik, E Solymosne

    2013-01-01

    To estimate the uncertainty of the sample size reduction step, each unit in laboratory samples of papaya and cucumber was cut into four segments in longitudinal directions and two opposite segments were selected for further homogenisation while the other two were discarded. Jackfruit was cut into six segments in longitudinal directions, and all segments were kept for further analysis. To determine the pesticide residue concentrations in each segment, they were individually homogenised and analysed by chromatographic methods. One segment from each unit of the laboratory sample was drawn randomly to obtain 50 theoretical sub-samples with an MS Office Excel macro. The residue concentrations in a sub-sample were calculated from the weight of segments and the corresponding residue concentration. The coefficient of variation calculated from the residue concentrations of 50 sub-samples gave the relative uncertainty resulting from the sample size reduction step. The sample size reduction step, which is performed by selecting one longitudinal segment from each unit of the laboratory sample, resulted in relative uncertainties of 17% and 21% for field-treated jackfruits and cucumber, respectively, and 7% for post-harvest treated papaya. The results demonstrated that sample size reduction is an inevitable source of uncertainty in pesticide residue analysis of large-sized crops. The post-harvest treatment resulted in a lower variability because the dipping process leads to a more uniform residue concentration on the surface of the crops than does the foliar application of pesticides.

  18. 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

  19. 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.

  20. Gas chromatographic determination of pesticide residues in white mustard.

    PubMed

    Słowik-Borowiec, Magdalena; Szpyrka, Ewa; Walorczyk, Stanisław

    2015-04-15

    A new analytical method employing gas chromatography coupled to electron capture and nitrogen phosphorus detection (GC-ECD/NPD) has been developed and validated for the screening and quantification of 51 pesticides in a matrix of high chlorophyll content - white mustard (Sinapis alba L.). For preparation of the sample extract, the citrate buffered QuEChERS procedure was followed. However certain changes were made to adapt the method to our needs and available laboratory resources. The sample size was reduced to 5 g, 10 mL water was added and exchange of solvent before GC analysis was done. The samples spiked with the target pesticides at the concentration level 0.01 mg/kg and a higher level (depending on the compound) yielded average recoveries in the range of 70-120% with relative standard deviations (RSDs) 0-19% except for HCB, S-metolachlor and teflubenzuron, and displayed very good linearity (R(2)>0.99) for nearly all the analytes. Limit of quantification was 0.01 mg/kg for the majority of the analytes. The expanded measurement uncertainties were estimated employing a "top-down" empirical model as being between 6% and 32% and yielding an average value of 18% (coverage factor k=2, confidence level 95%). PMID:25466117

  1. Pesticide residue analysis of soil, water, and grain of IPM basmati rice.

    PubMed

    Arora, Sumitra; Mukherji, Irani; Kumar, Aman; Tanwar, R K

    2014-12-01

    The main aim of the present investigations was to compare the pesticide load in integrated pest management (IPM) with non-IPM crops of rice fields. The harvest samples of Basmati rice grain, soil, and irrigation water, from IPM and non-IPM field trials, at villages in northern India, were analyzed using multi-pesticide residue method. The field experiments were conducted for three consecutive years (2008-2011) for the successful validation of the modules, synthesized for Basmati rice, at these locations. Residues of tricyclazole, propiconazole, hexconazole, lambda cyhalothrin, pretilachlor chlorpyrifos, DDVP, carbendazim, and imidacloprid were analyzed from two locations, Dudhli village of Dehradun, Uttrakhand and Saboli and Aterna village of Sonepat, Haryana. The pesticide residues were observed below detectable limit (BDL) (<0.001-0.05 μg/g) in all 24 samples of rice grains and soil under IPM and non-IPM trials. Residues were below detection level (<0.001-0.05 μg/L) in irrigation water samples (2008-09). Residues of tricyclazole and carbendazim, analyzed from same locations, revealed pesticide residues as BDL (<0.001-0.05 μg/g) in all 40 samples of Basmati rice grains and soil. It was also observed as BDL (<0.001-0.05 μg/L) for 12 water samples (2009-2010). The residues of tricyclazole, propioconazole, chlorpyrifos, hexaconazole, pretilachlor, and λ-cyhalothrin were also found as BDL (<0.001-0.05 μg/g) in 40 samples of Basmati rice grains and soil and 12 water samples (<0.001-0.05 μg/L) (2010-2011).

  2. 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

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. Assessment of uncertainty in a probabilistic model of consumer exposure to pesticide residues in food.

    PubMed

    Ferrier, Helen; Shaw, George; Nieuwenhuijsen, Mark; Boobis, Alan; Elliott, Paul

    2006-06-01

    The assessment of consumer exposure to pesticides is an important part of pesticide regulation. Probabilistic modelling allows analysis of uncertainty and variability in risk assessments. The output of any assessment will be influenced by the characteristics and uncertainty of the inputs, model structure and assumptions. While the use of probabilistic models is well established in the United States, in Europe problems of low acceptance, sparse data and lack of guidelines are slowing the development. The analyses in the current paper focused on the dietary pathway and the exposure of UK toddlers. Three single food, single pesticide case studies were used to parameterize a simple probabilistic model built in Crystal Ball. Data on dietary consumption patterns were extracted from National Diet and Nutrition Surveys, and levels of pesticide active ingredients in foods were collected from Pesticide Residues Committee monitoring. The effect of uncertainty on the exposure estimate was analysed using scenarios, reflecting different assumptions related to sources of uncertainty. The most influential uncertainty issue was the distribution type used to represent input variables. Other sources that most affected model output were non-detects, unit-to-unit variability and processing. Specifying correlation between variables was found to have little effect on exposure estimates. The findings have important implications for how probabilistic modelling should be conducted, communicated and used by policy and decision makers as part of consumer risk assessment of pesticides.

  11. 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

  12. 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

  13. 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.

  14. Assessment of pesticide residues in Karaboğaz Lake from Kızılırmak Delta, Turkey.

    PubMed

    Yurtkuran, Zeynep; Saygı, Yasemin

    2013-08-01

    Monitoring of pesticide residues in water and sediments was conducted for the coastal shallow Karaboğaz Lake, northern Turkey. During a one-year study period, eight pesticides (malathion, etofenprox, molinate, oxamyl, propamocarb hydrochloride, tebufenozide, linuron, piperonyl butoxide) were detected in water and in sediments, all at μg/L and μg/kg concentrations, respectively. Temporal variation in pesticide concentrations was observed. Highest pesticide concentrations in water and sediment were from tebufenozide and etofenprox, respectively. Aquatic risk assessments revealed that out of eight pesticides detected, three showed unaccaptable risk: malathion, oxamyl and etofenprox.

  15. Effects of ozone microbubble treatment on removal of residual pesticides and quality of persimmon leaves.

    PubMed

    Ikeura, Hiromi; Hamasaki, Sadahiro; Tamaki, Masahiko

    2013-05-01

    This study investigated the effects of ozone microbubble (OMCB) treatment on the removal of residual fenitrothion (FT) and benomyl pesticides from red and green persimmon leaves, and also the treatment effect on the leaf colours, physical properties and flavour. The continuous bubbling OMCB treatment was more effective than the non-bubbling OMCB treatments at reducing the FT and benomyl agricultural pesticide residues from both the red and green persimmon leaves. Moreover, the bubbling OMCB treatment had no effect on the colour and pulling strength of the leaves. These results indicate that the treatment by bubbling OMCB is an extremely effective method for removing the residues of FT and benomyl in persimmon leaves and has relatively little effect on leaf quality characteristics.

  16. Determination of pesticide residue transfer rates (percent) from dried tea leaves to brewed tea.

    PubMed

    Wang, Jian; Cheung, Wendy; Leung, Daniel

    2014-01-29

    This paper presents a study on pesticide residue transfer rates (%) from dried tea leaves to brewed tea. In the study, a brewing procedure simulated the preparation of a hot tea drink as in routine. After brewing, pesticide residues were extracted from brewed tea using a method known as QuEChERS (quick, easy, cheap, effective, rugged, and safe). An UHPLC/ESI-MS/MS method was developed and validated to identify and quantify up to 172 pesticides in both tea leaves and brewed tea samples. Quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or a chemical analogue as internal standards, and the calibration curves consisted of six points (0.4, 2.0, 8.0, 16.0, 24.0, and 40.0 μg/L equivalent in sample). The method was validated at four concentration levels (4.0, 12, 20.0, and 32.0 μg/L equivalent in sample) using five different brewed tea matrices on two separate days per matrix. Method performance parameters included overall recovery, intermediate precision, and measurement uncertainty, which were evaluated according to a nested experimental design. Approximately, 95% of the pesticides studied had recoveries between 81 and 110%, intermediate precision ≤20%, and measurement uncertainty ≤40%. From a pilot study of 44 incurred tea samples, pesticide residues were examined for their ability to transfer from dried tea leaves to brewed tea. Each sample, both tea leaves and brewed tea, was analyzed in duplicate. Pesticides were found to have different transfer rates (%). For example, imidacloprid, methomyl, and carbendazim had transfer rates of 84.9, 83.4, and 92.4%, respectively.

  17. Evaluation of pesticide residues of organochlorine in vegetables and fruits in Qatar: statistical analysis.

    PubMed

    Al-Shamary, Noora M; Al-Ghouti, Mohammad A; Al-Shaikh, Ismail; Al-Meer, Saeed H; Ahmad, Talaat A

    2016-03-01

    The study aimed to examine the residues of organochlorines pesticides (OCPs) in vegetables and fruits in Qatar. A total of 127 samples was studied. Ninety percent of the imported samples recorded residues above the maximum residue levels (MRLs). The most frequently detected OCP in the samples was heptachlor (found in 75 samples). In the comparisons between the washed and unwashed samples, no significant differences were observed (P > 0.05). However, the effect of washing process with tap water depended on the type of vegetables and fruits.

  18. 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.

  19. A residue-free green synergistic antifungal nanotechnology for pesticide thiram by ZnO nanoparticles.

    PubMed

    Xue, Jingzhe; Luo, Zhihui; Li, Ping; Ding, Yaping; Cui, Yi; Wu, Qingsheng

    2014-07-14

    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.

  20. 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.

  1. 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

  2. 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

  3. 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...

  4. Modelling non-systemic pesticide residues in fruits with initial deposit variability and weather effects.

    PubMed

    Huo, R; Salazar, J D; Hyder, K; Xu, X-M

    2007-11-01

    A flexible and generic model was developed to predict the decline of residues of a non-systemic pesticide for both single and multi-spray situations as well as for different tree canopy zones. The model predicts not only the average residue levels, but also the confidence interval of the residues through either a deterministic or a stochastic approach. This generic model includes several key aspects of residue fates in the environment: initial deposit, physical loss and growth dilution. The model considers a tree canopy in three distinct zones for which initial deposition of pesticides may differ. In addition to predicting the average residue within each zone, it also estimates the 95 and 99% confidence intervals of residues on individual fruit within each zone. For the purpose of evaluation, this model was parameterized specifically for captan, one of the most important non-systemic fungicides used to control disease in horticultural crops. The observed average initial deposit for each zone was used in the evaluation. The overall correlation between predicted average residues and those observed on apple fruit in two applications was 0.93. Confidence intervals were also predicted accurately.

  5. Estimation of measurement uncertainty associated to the determination of pesticide residues: a case study.

    PubMed

    Stefanelli, Patrizia; Barbini, Danilo Attard; Girolimetti, Silvana; Dommarco, Roberto

    2012-09-01

    In the analytical analysis the measurement uncertainty is a quantitative indicator of the confidence describing the range around a reported or experimental result within which the true value can be expected. Several approaches can be used to estimate the measurement uncertainty associated to the analysis of pesticide residues: a) the top-down, the estimation can be referred to default values; b) the bottom-up the estimation is related to the uncertainty sources. Concerning the bottom-up approach, the following contributions have been investigated: weight of sample, calibration solutions, final volume of sample and intermediate repeatability studies. The commodity/residue combination selected in this study was celery/tau-fluvalinate pesticide. Tau-fluvalinate is a broad-spectrum insecticide in the pyrethroid class of pesticides. The Maximum Residue Limit (MRL) of tau-fluvalinate in celery has been set at 0.01 mg/kg. The tau- Fluvalinate showed two chromatographic peaks. Since the individual standards are not available, the two peaks were integrated separately and the instrumental responses were added. The total residue was calculated on the basis of resulted peaks. The present work aims to compare the uncertainty estimated by experimental data using repeated analysis (n = 12) of a real sample and a spiked sample. The relative expanded uncertainty for two data set, incurred and spiked, was 22 % and 20 %, respectively. No differences were observed from repeated determinations of real samples and spiked samples.

  6. Organochlorine pesticide residues in bed sediments of the San Joaquin River, California

    USGS Publications Warehouse

    Gilliom, Robert J.; Clifton, Daphne G.

    1990-01-01

    Bed sediments of the San Joaquin River and its tributaries were sampled during October 7–11, 1985, and analyzed for organochiorine pesticide residues in order to determine their areal distribution and to evaluate and prioritize needs for further study. Residues of DDD, DDE, DDT, and dieldrin are widespread in the fine-grained bed sediments of the San Joaquin River and its tributaries despite little or no use of these pesticides for more than 15 years. The San Joaquin River has among the highest bed-sediment concentrations of DDD, DDE, DDT, and dieldrin residues of major rivers in the United States. Concentrations of all four pesticides were correlated with each other and with the amount of organic carbon and fine-grained particles in the bed sediments. The highest concentrations occurred in bed sediments of westside tributary streams. Potential tributary loads of DDD, DDE, DDT, and dieldrin to the San Joaquin River were computed from bed-sediment concentrations and data on streamfiow and suspended-sediment concentration in order to identify the general magnitude of differences between streams and to determine study priorities. The estimated loads indicate that the most important sources of residues during the study period were Salt Slough because of a high load of fine sediment, and Newman Wasteway, Orestimba Creek, and Hospital Creek because of high bed-sediment concentrations. Generally, the highest estimated loads of DDD, DDE, DDT, and dieldrin were in Orestimba and Hospital Creeks.

  7. [Study on experiment of absorption spectroscopy detection of pesticide residues of carbendazim in orange juice].

    PubMed

    Ji, Ren-Dong; Chen, Meng-Lan; Zhao, Zhi-Min; Zhu, Xing-Yue; Wang, Le-Xin; Liu, Quan-Jin

    2014-03-01

    Absorption spectra were studied for the carbendazim, in the mixed solution of orange juice and carbendazim using spectrophotometer. The most intensive characteristic peak (285 nm) was found in the spectrum of carbendazim standard solution. Compared with the carbendazim drug solution, the peak position of absorption spectrum has the blue shift (285-280 nm) when carbendazim (0.28 mg x mL(-1))was added in the orange juice. So that we can conclude that interaction happened between the orange juice and carbendazim. Through the method of least squares fitting, the prediction models between the absorbance of orange juice and carbendazim content was obtained with a good linear relationship. The linear function model was: I = 2.41 + 9.26x, the correlation coefficient was 0.996, and the recovery was: 81%-102%. According to the regression model, we can obtain the amount of carbendazim pesticide residues in orange juice. It was verified that the method of using ultraviolet-visible absorption spectra was feasible to detect the carbendazim residues in orange juice. The result proved that it is possible to detect pesticide residues of carbendazim in orange juice, and it can meet the needs of rapid analysis. This study provides a new way for the detection of pesticide residues.

  8. Pesticide residue screening using a novel artificial neural network combined with a bioelectric cellular biosensor.

    PubMed

    Ferentinos, Konstantinos P; Yialouris, Costas P; Blouchos, Petros; Moschopoulou, Georgia; Kintzios, Spyridon

    2013-01-01

    We developed a novel artificial neural network (ANN) system able to detect and classify pesticide residues. The novel ANN is coupled, in a customized way, to a cellular biosensor operation based on the bioelectric recognition assay (BERA) and able to simultaneously assay eight samples in three minutes. The novel system was developed using the data (time series) of the electrophysiological responses of three different cultured cell lines against three different pesticide groups (carbamates, pyrethroids, and organophosphates). Using the novel system, we were able to classify correctly the presence of the investigated pesticide groups with an overall success rate of 83.6%. Considering that only 70,000-80,000 samples are annually tested in Europe with current conventional technologies (an extremely minor fraction of the actual screening needs), the system reported in the present study could contribute to a screening system milestone for the future landscape in food safety control.

  9. 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

  10. 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

  11. 76 FR 2110 - Notice of Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-12

    ... Environmental protection, Agricultural commodities, Feed additives, Food additives, Pesticides and pests... affected by this action if you are an agricultural producer, food manufacturer, or pesticide manufacturer... production (NAICS code 112). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code...

  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.

  13. 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

  14. 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, ...

  15. Pesticide residues in air from coastal environment, south India.

    PubMed

    Rajendran, R B; Venugopalan, V K; Ramesh, R

    1999-10-01

    Chlorinated pollutants are transported through atmosphere. India is one of the point source countries for these pollutants [1]. In this study the concentration of DDT and HCH were evaluated in air from a tropical coastal environmental (at Parangipettai--southeast coast of India). DDT and HCH ranged in concentrations from 0.16 to 5.93 ng m-3 and 1.45 to 35.6 ng m-3 respectively. The ban on DDT in agriculture is reflected from the low residue levels recorded, predominantly by metabolites other than the parent compounds. PMID:10520487

  16. 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 define