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Sample records for organophosphorus pesticide residues

  1. 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.

  2. Organochlorine and organophosphorus pesticide residues in food from Egyptian local markets.

    PubMed

    Dogheim, S M; Gad Alla, S A; el-Syes, S M; Almaz, M M; Salama, E Y

    1996-01-01

    A market basket survey was conducted to monitor organochlorine and organophosphorus pesticide residues in potatoes, citrus fruits, and fish collected from local Egyptian markets. Maximum Residue Limits (MRLs) of the Codex Committee on Pesticide Residues for gamma-hexachlorocyclohexane (HCH) in potatoes were exceeded in 8 samples and for DDT in 2 samples. The aging of HCH and DDT indicated a recent use of both pesticides during the potato storage period between cultivation seasons. However, such use is illegal because HCH mixture isomers (gammaxane) and DDT have been officially prohibited from agricultural use in Egypt since 1980. The highest residue levels of fenitrothion (3.8 ppm) in potatoes may be due to its repeated use before and after harvest. No organochlorine pesticide residues were found in citrus fruits. None of the detected organophosphorus pesticides exceeded their MRLs. HCH and DDT residue limits were exceeded in 5 and 7 fish samples, respectively, collected from 12 markets throughout the country. The heptachlor MRL was violated in only one fish sample (3.9 ppm).

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

    PubMed

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

    2008-10-01

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

  4. 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

  5. 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).

  6. Organophosphorus pesticide residues in milled rice (Oryza sativa) on the Chinese market and dietary risk assessment.

    PubMed

    Chen, Chen; Li, Yun; Chen, Mingxue; Chen, Zhijun; Qian, Yongzhong

    2009-03-01

    The present study investigates the occurrence of acetylcholinesterase (AChE)-inhibiting organophosphorus (OP) pesticide residues in milled rice samples obtained form local markets in China during the period 2004-2006 and estimates their cumulative exposure. Concentrations of OP pesticides were determined by gas chromatography with flame photometric detection (GC-FPD). The results showed that 9.3% of the samples contained detectable residues of at least one of the seven target OP pesticides (chlorpyrifos, dichlorvos, omethoate, methamidophos, parathion-methyl, parathion and triazophos) mainly used for agriculture in China, with concentrations ranging 0.011-1.756 mg kg(-1). Rice consumption data was obtained from an individual food consumption survey. Relative potency factors (RPFs) for each pesticide were calculated with methamidophos as the index compound (IC), using 1- or 2-year chronic non-observed adverse effect levels (NOAEL) for AChE inhibition, mostly in rat brain, obtained from international evaluations of pesticides. Exposure to AChE-inhibiting pesticides for the population above 7 years old at P99.9 represented 52-94.5% of the acceptable daily intake (ADI) expressed as methamidophos. Estimated exposure for children aged 2-4 and 4-7 years at P99.9 were 119 and 104.3% of the ADI level, respectively. This study suggests that a yearly monitoring program for OP pesticide residues and strict implementation of the national safety standard for milled rice is necessary.

  7. 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.

  8. Construction of genetically engineered bacteria that degrades organophosphorus pesticide residues and can be easily detected by the fluorescence.

    PubMed

    Li, Qin; Wang, Pan; Chen, Rui; Li, Wei; Wu, Yi-Jun

    2014-01-01

    Organophosphorus compounds (OPs) are widely used in agriculture and industry and there is increased concern about their toxicological effects in the environment. Bioremediation can offer an efficient and cost-effective option for the removal of OPs. Herein, we describe the construction of a genetically engineered microorganism (GEM) that can degrade OPs and be directly detected and monitored in the environment using an enhanced green fluorescent protein (EGFP) fusion strategy. The coding regions of EGFP, a reporter protein that can fluoresce by itself, and organophosphorus hydrolase (OPH), which has a broad substrate specificity and is able to hydrolyse a number of organophosphorus pesticides, were cloned into the expression vector pET-28b. The fusion protein of EGFP-OPH was expressed in E. coli BL21 (DE3) and the protein expression reached the highest level at 11 h after isopropyl beta-D-thiogalactopyranoside induction. The fluorescence of the GEM was detected by fluorescence spectrophotometry and microscopy, and its ability to degrade OPs was determined by OPH activity assay. Those GEM that express the fusion protein (EGFP and OPH) exhibited strong fluorescence intensity and also potent hydrolase activity, which could be used to degrade organophosphorus pesticide residues in the environment and can also be directly monitored by fluorescence.

  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.

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

    PubMed

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

    2016-03-01

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

  11. 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.

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

    PubMed Central

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

    2012-01-01

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

  13. CUMULATIVE RISK ANALYSIS FOR ORGANOPHOSPHORUS PESTICIDES

    EPA Science Inventory

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

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

  14. Determination of 15 organophosphorus pesticides in Italian raw milk.

    PubMed

    Gazzotti, Teresa; Sticca, Patrizia; Zironi, Elisa; Lugoboni, Barbara; Serraino, Andrea; Pagliuca, Giampiero

    2009-02-01

    A study was conducted on raw cow's milk to measure the residues of 15 organophosphorus pesticides used as dairy cattle ectoparasiticides or as insecticides in crops used for animal feed. For this purpose a previously devised method was improved and validated. The samples were collected directly from tank trucks during delivery of 3,974 tonnes of raw milk at nine Italian dairy plants. Approximately 4.4% of the 298 samples analyzed contained residues only in traces. The main pollutant was chlorpyriphos.

  15. 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)

  16. 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...

  17. 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

  18. 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.

  19. 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

  20. [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.

  1. 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...

  2. 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.

  3. Photodegradation of organophosphorus pesticides in honey medium.

    PubMed

    Yuan, Zhimin; Yao, Jun; Liu, Haijun; Han, Jun; Trebše, Polonca

    2014-10-01

    Honey can be polluted due to environmental pollution and misuse of beekeeping practices. In the present study, photodegradation experiments of organophosphorus pesticides (coumaphos, methyl parathion and fenitrothion) in honey medium were conducted using Atlas Suntest simulator CPS+ as a sunlight producer. Photodegradation experiments were conducted under three different intensities as 250W/m(2), 500W/m(2) and 750W/m(2) to evaluate the impact of sunlight intensity on removal of OPs in honey medium. Significant decreases of three OPs' concentrations were observed. Coumaphos showed the highest degradability, reaching a degradation percentage of 90 percent within 15min. After 1h irradiation, residual percentages of coumaphos were 6.62 percent for 250W/m(2), 3.48 percent for 500W/m(2) and 2.98 percent for 750W/m(2), respectively. Methyl parathion and fenitrothion also could be removed through photodegradation efficiently. After 1h irradiation, the residual percentages of methyl parathion and fenitrothion under 750W/m(2) sunlight irradiation were 26.89 percent and 16.70 percent, respectively. Intensity of sunlight showed a positive impact on removal of OPs in honey medium. The higher intensity, the lower residual percentage. Photodegradation of three OPs fitted well with pseudo-first order kinetics. Half-lives calculated from pseudo-first order kinetics were 17.61min (250W/m(2)), 16.67min (500W/m(2)) and 17.58min (750W/m(2)) for coumaphos, 57.62min (250W/m(2)), 34.13min (500W/m(2)) and 31.69min (750W/m(2)) for methyl parathion and 144.70min (250W/m(2)), 95.47min (500W/m(2)) and 22.57min (750W/m(2)) for fenitrothion, respectively. Most of the three OPs could dissipate in a short time under sunlight irradiation. Photodegradation could be accepted as an appropriate method for the removal of OPs in honey medium.

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

    PubMed

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

    2010-01-01

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

  5. 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

  6. 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...

  7. 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.

  8. Maternal exposure to the mixture of organophosphorus pesticides induces reproductive dysfunction in the offspring.

    PubMed

    Yu, Yan; Yang, Aimin; Zhang, Jinghua; Hu, Senke

    2013-09-01

    Organophosphorus pesticide residues are found in many food samples due to increasing use of multiple organophosphorus pesticides (OPs) in agriculture. Toxicity of individual organophosphorus has been well-studied in previous epidemiological and laboratory investigations. This study focused on reproductive toxicity of perinatal exposure to the mixture of organophosphorus pesticides (MOPs). The MOPs consists of three most commonly used pesticides, i.e., Dichlorovos, Dimethoate, and Malathion which individually does not cause significant effects on the reproductive system at the similar concentration levels based on previous studies. Using the Sprague-Dawley rats, we established a perinatal exposure model by oral gavage and observed significant endometrial hyperplasia and thickened uterine walls in the F0 rats after administration of high doses of the MOPs. We further monitored several key developmental and behavioral indices in the F1 generation after maternal exposure to the MOPs, and observed significantly delayed physical development and weakened mental development. Moreover, we found increased weights of the reproductive organs (the uterus and the testis) and abnormal levels of key sex hormones (progestin and testosterone) in the MOPs groups. It is more important that we observed a significantly lower pregnancy rate and live birth rate in the high-dose MOPs group. These results indicate that the MOPs may be more detrimental to the maternal endometria and the reproductive functions in the offspring than individual organophosphorus.

  9. 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.

  10. 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.

  11. Determination of Levels of Organochlorine, Organophosphorus, and Pyrethroid Pesticide Residues in Vegetables from Markets in Dar es Salaam by GC-MS

    PubMed Central

    Khamis, Farhat A.; Lugwisha, Esther H. J.

    2017-01-01

    This study investigated the levels of pesticides and metabolites in vegetables from major markets in Dar es Salaam city, Tanzania. Samples of fresh cabbage, spinach, and onions from the markets were analysed for pesticide residues. Extraction was performed using acetone followed by dichloromethane : cyclohexane mixture and the extracts were cleaned up using Florisil. The compounds were determined by gas chromatography-mass spectrometry (GC-MS). Pesticides and metabolites were detected in 72.2% of the samples. The detected pesticide residues and their highest mean concentrations were p,p′-DDT 4.00 × 10−3 mg/kg, p,p′-DDD 6.40 × 10−1 mg/kg, o,p′-DDD 1.00 × 10−2 mg/kg, α-endosulfan 6.00 × 10−1 mg/kg, β-endosulfan 2.10 × 10−1 mg/kg, chlorpyrifos 3.00 mg/kg, and cypermethrin 4.00 × 10−2 mg/kg. The most frequently detected compounds were p,p′-DDD and chlorpyrifos. The order of contamination was spinach > cabbage > onions. Generally, there were no significant variations in concentrations of pesticide residues among samples and sampling sites, which indicated similarities in contamination patterns. The concentrations of contaminants were above the maximum residue limits (MRLs) in 33.3–50% of the samples. The findings indicated risks and concerns for public health. PMID:28280510

  12. Catanionic surfactant ambient cloud point extraction and high-performance liquid chromatography for simultaneous analysis of organophosphorus pesticide residues in water and fruit juice samples.

    PubMed

    Seebunrueng, Ketsarin; Santaladchaiyakit, Yanawath; Soisungnoen, Phimpha; Srijaranai, Supalax

    2011-09-01

    A mixed anionic-cationic surfactant cloud point extraction (CPE) has been developed using sodium dodecyl sulfate (SDS) and tetrabutylammonium bromide (TBABr) for the extraction and preconcentration of organophosphorus pesticides (OPPs) at ambient temperature before analysis by high-performance liquid chromatography. The studied OPPs were azinphos-methyl, parathion-methyl, fenitrothion, diazinon, chlorpyrifos, and prothiophos. The optimum conditions of the mixed anionic-cationic CPE were 50 mmol L(-1) SDS, 100 mmol L(-1) TBABr, and 10% (w/v) NaCl. The extracted OPPs were successfully separated within 11 min using the conditions of a Waters Symmetry C8 column, a flow rate of 0.8 mL min(-1), a gradient elution of methanol and water, and detection at 210 nm. Linearity was found over the range 0.05-5 μg mL(-1), with the correlation coefficients higher than 0.996. The enrichment factor of the target analytes was in the range 6-11, which corresponds to their limits of detection from 1 to 30 ng mL(-1). High precisions (intra-day and inter-day) were obtained with relative standard deviation <1.5% (t(R)) and 10% (peak area). Accuracies (% recovery) of the different spiked OPP concentrations were 82.7-109.1% (water samples) and 80.3-113.3% (fruit juice samples). No contamination by the OPPs was observed in any studied samples.

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

    PubMed

    Chung, Stephen W C; Chan, Benny T P

    2010-07-16

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

  14. 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....

  15. New insights on molecular interactions of organophosphorus pesticides with esterases.

    PubMed

    Mangas, Iris; Estevez, Jorge; Vilanova, Eugenio; França, Tanos Celmar Costa

    2017-02-01

    Organophosphorus compounds (OPs) are a large and diverse class of chemicals mainly used as pesticides and chemical weapons. People may be exposed to OPs in several occasions, which can produce several distinct neurotoxic effects depending on the dose, frequency of exposure, type of OP, and the host factors that influence susceptibility and sensitivity. These neurotoxic effects are mainly due to the interaction with enzyme targets involved in toxicological or detoxication pathways. In this work, the toxicological relevance of known OPs targets is reviewed. The main enzyme targets of OPs have been identified among the serine hydrolase protein family, some of them decades ago (e.g. AChE, BuChE, NTE and carboxylesterases), others more recently (e.g. lysophospholipase, arylformidase and KIA1363) and others which are not molecularly identified yet (e.g. phenylvalerate esterases). Members of this family are characterized by displaying serine hydrolase activity, containing a conserved serine hydrolase motif and having an alpha-beta hydrolase fold. Improvement in Xray-crystallography and in silico methods have generated new data of the interactions between OPs and esterases and have established new methods to study new inhibitors and reactivators of cholinesterases. Mass spectrometry for AChE, BChE and APH have characterized the active site serine adducts with OPs being useful to detect biomarkers of OPs exposure and inhibitory and postinhibitory reactions of esterases and OPs. The purpose of this review is focus specifically on the interaction of OP with esterases, mainly with type B-esterases, which are able to hydrolyze carboxylesters but inhibited by OPs by covalent phosphorylation on the serine or tyrosine residue in the active sites. Other related esterases in some cases with no-irreversible effect are also discussed. The understanding of the multiple molecular interactions is the basis we are proposing for a multi-target approach for understanding the

  16. 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.

  17. 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%).

  18. 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

  19. 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.

  20. 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

  1. 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, ...

  2. 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...

  3. Organophosphorus hydrolase (OpdB) of Lactobacillus brevis WCP902 from kimchi is able to degrade organophosphorus pesticides.

    PubMed

    Islam, Shah Md Asraful; Math, Renukaradhya K; Cho, Kye Man; Lim, Woo Jin; Hong, Su Young; Kim, Jong Min; Yun, Myoung Geun; Cho, Ji Joong; Yun, Han Dae

    2010-05-12

    Lactobacillus brevis WCP902 that is capable of biodegrading chlorpyrifos was isolated from kimchi. The opdB gene cloned from this strain revealed 825 bp, encoding 274 aa, and an enzyme molecular weight of about 27 kDa. OpdB contains the same Gly-X-Ser-X-Gly motif found in most bacterial and eukaryotic esterase, lipase, and serine hydrolases, yet it is a novel member of the GDSVG family of esterolytic enzymes. Its conserved serine residue, Ser82, is significantly involved with enzyme activity that may have application for removing some pesticides. Optimum organophosphorus hydrolase (OpdB) activity appeared at pH 6.0 and 35 degrees C and during degradation of chlorpyrifos, coumaphos, diazinon, methylparathion, and parathion.

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

    PubMed

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

    2016-09-01

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

  5. 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.

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

    PubMed

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

    2010-02-01

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

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

    PubMed

    Uchimiya, Minori; Wartelle, Lynda H; Boddu, Veera M

    2012-03-28

    Sorption and degradation are the primary processes controlling the efficacy and runoff contamination risk of agrochemicals. Considering the longevity of biochar in agroecosystems, biochar soil amendment must be carefully evaluated on the basis of the target agrochemical and soil types to achieve agricultural (minimum impact on efficacy) and environmental (minimum runoff contamination) benefits. In this study, sorption-desorption isotherms and kinetics of triazine (deisopropylatrazine) and organophosphorus (malathion, parathion, and diazinon) pesticides were first investigated on various soil types ranging from clayey, acidic Puerto Rican forest soil (PR) to heavy metal contaminated small arms range (SAR) soils of sandy and peaty nature. On PR, malathion sorption did not reach equilibrium during the 3 week study. Comparison of solution-phase molar phosphorus and agrochemical concentrations suggested that degradation products of organophosphorus pesticides were bound on soil surfaces. The degree of sorption on different soils showed the following increasing trend: deisopropylatrazine < malathion < diazinon < parathion. While sorption of deisopropylatrazine on SAR soils was not affected by diazinon or malathion, deisopropylatrazine suppressed the sorption of diazinon and malathion. Deisopropylatrazine irreversibly sorbed on biochars, and greater sorption was observed with higher Brunauer-Emmett-Teller surface area of biochar (4.7-2061 mg g(-1)). The results suggested the utility of biochar for remediation of sites where concentrations of highly stable and mobile agrochemicals exceed the water-quality benchmarks.

  8. A thin film electro-acoustic enzyme biosensor allowing the detection of trace organophosphorus pesticides.

    PubMed

    Chen, Da; Wang, Jingjing; Xu, Yan; Zhang, Luyin

    2012-10-01

    We report an analytical method using a thin film electro-acoustic resonator for the detection of organophosphorus pesticides. The acetylcholinesterase (AChE) enzyme was immobilized on the surface of the resonator. In the presence of organophosphorus compounds, the degree of inhibitory effect of organophosphorus compounds on the AChE activity and the concentration of pesticides were detected in real time by measuring the frequency shift of the resonator. The proposed device has a remarkably low detection limit of 1.8×10(-11)M and obvious advantages such as small size, simple operation, and integrated circuit compatibility, providing a promising tool for pesticide analysis.

  9. 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.

  10. Highly sensitive detection of organophosphorus pesticides by acetylcholinesterase-coated thin film bulk acoustic resonator mass-loading sensor.

    PubMed

    Chen, Da; Wang, Jingjing; Xu, Yan; Li, Dehua; Zhang, Luyin; Li, Zhaoxin

    2013-03-15

    An acetylcholinesterase-coated thin film bulk acoustic resonator has been developed for the detection of organophosphorus pesticides. The thin film bulk acoustic resonator acts as a robust mass-sensitive transducer for bio-sensing. This device works in thickness shear mode with a resonance at 1.97 GHz. The detection is based on the inhibitory effects of organophosphorus compounds on the enzymatic activity of the acetylcholinesterase immobilized on one of the faces of the acoustic resonator. The enzyme reaction in the substrate solution and the inhibitory effect is observed are real time by measuring the frequency shift. The presence of organophosphorus pesticides can be detected from the diminution of the frequency shift compared with the levels found in their absence. The device exhibits linear responses, good reproducibility, simple operation, portability and a low detection limit of 5.3×10(-11) M for paraoxon. The detection results of organophosphorus pesticide residues in practical samples show that the proposed sensor has the feasibility and sensing accuracy comparable to gas chromatography.

  11. 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.

  12. 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

  13. 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...

  14. 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...

  15. 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

  16. 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

  17. Modulation of immune response by organophosphorus pesticides: fishes as a potential model in immunotoxicology.

    PubMed

    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.

  18. 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.

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

    PubMed

    Jokanović, Milan

    2009-10-28

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

  20. The Fate of Organophosphorus Pesticides during Camellia Oil Production.

    PubMed

    Liu, Yihua; Mo, Runhong; Zhong, Donglian; Shen, Danyu; Ni, Zhanglin; Tang, Fubin

    2015-08-01

    The purpose of this study was to investigate the fate of organophosphorus pesticides (OPs) during camellia oil production process, from camellia fruit to the final oil product. The results showed that the OPs were mainly distributed in the peel of camellia fruit, basically above 40% after the pesticide application of 7 d (P < 0.05). A small amount of OPs could enter into the seed and convert to crude camellia oil, with the concentration of 19.5 to 548.2 mg/L. In addition, metabolites of OPs (25.7 to 768.9 mg/L) could be detected in the crude camellia oil. Moreover, the refining process (degumming, deacidfying, bleaching) had a significant effect on the removal of OPs from the crude camellia oil (P < 0.05), and the effect was related to the octanol-water partition constant (LogP) of pesticide. The larger the LogP, the more stable the OPs were during refining process. The final refined camellia oil was found to have no detectable levels of OPs metabolite.

  1. 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

  2. [Terahertz spectroscopic investigation of organophosphorus pesticide parathion-methyl].

    PubMed

    Yan, Zhi-Gang; Zheng, Song; Xie, Qiang-Jun; Zhou, Ze-Kui

    2009-10-01

    The present paper reports the theoretical and experimental vibrational spectra of organophosphorus pesticide parathion-methyl in the frequency range from 0.2 to 2.0 THz respectively. Under the room temperature and nitrogen conditions, the absorption peaks were found at 0.65, 1.33, 1.81 and 1.91 THz, and the average refractive index was 1.39 based on the terahertz time-domain spectroscopy (THz-TDS). In parallel with the experimental study, density functional theory (DFT) was applied to obtain the structure and vibrational frequencies of parathion-methyl in the terahertz region. The calculated results are in reasonable agreement with the experimental data. The absorption features are caused by the collective vibrational and torsional modes, and the different absorption peaks correspond to different vibrational modes.

  3. Presence of organophosphorus pesticide oxygen analogs in air samples

    NASA Astrophysics Data System (ADS)

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

    2013-02-01

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

  4. New experimental Oximes in the management of organophosphorus pesticides poisoning.

    PubMed

    Barelli, A; Soave, P M; Del Vicario, M; Barelli, R

    2011-12-01

    Organophosphorus compounds (OPCs) are widely used in agriculture as pesticides and occasionally in industrial settings. They have also been developed as warfare nerve agents. OPCs poisoning from intentional, accidental, and occupational exposure is a major public health problem, especially across the rural developing world. The main toxic mechanism of OPCs is the inhibition of the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), resulting in accumulation of acetylcholine (ACh) at the synapse with cholinergic crisis and possible death. Exposure to even small amounts of an OPC can be fatal and death is usually caused by respiratory failure. Standard treatment involves the administration of intravenous atropine and an oxime to counteract acetylcholinesterase inhibition at the synapse, but the usefulness of oximes is still debated. During more than five decades, pyridinium oximes have been developed as therapeutic agents used in the medical treatment of poisoning with OPCs. They act by reactivation of AChE inhibited by OPCs. However, their activity in poisonings with pesticides and warfare nerve agents is different, and there is still no universal oxime sufficiently effective against all known OPCs. The aim of this article was to review the most recent findings in this field and compare the protection conferred by the new K-oximes and sugar oximes with the effect of the four recommended pyridinium oximes (pralidoxime, obidoxime, trimedoxime, and HI-6), in the search for a broad-spectrum AChE reactivator.

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

    USGS Publications Warehouse

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

    1981-01-01

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

  6. 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...

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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
    ...

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

    PubMed

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

    2014-01-01

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

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

    PubMed

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

    2015-03-04

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

  15. The occurrence and risk assessment of five organophosphorus pesticides in river water from Shangyu, China.

    PubMed

    Chen, Hao; Zhu, Jianqiang; Li, Zhe; Chen, An; Zhang, Quan

    2016-11-01

    Organophosphorus pesticides (OPs), which are some of the most extensively used pesticides, have drawn much attention in recent years owing to their ubiquity as well as the potential ecological and health risks they pose to aquatic organisms and even to humans. In this study, we investigated the residue of five OPs in 49 river cross sections in Shangyu, Zhejiang province, China, a rainy region with relatively developed agriculture. Correlations analysis, principal component analysis, and cluster analysis were conducted. The results showed that dichlorvos exhibited the highest concentrations (0.01 to 5.63 μg/L) among the OPs in most monitoring sites. Weak positive correlations were found between methyl parathion and dichlorvos as well as malathion and dimethoate. The principal component analysis and cluster analysis indicated a correlation among these river cross sections. We then calculated the hazard index (HI) to estimate the potential adverse health effects. The mean HI presented no risk to adults but showed potential health risks to children, with values of 0.285, 0.228, and 0.166 for dichlorvos, methyl parathion, and dimethoate, respectively. Our study will help elucidate the potential risks of OPs and their residues in the rivers of Shangyu in the Zhejiang province in China and will be beneficial for managing water quality and will provide valuable suggestions to local policy makers. Graphical abstract Comparison of the ∑5OPs concentrations among 49 river cross sections.

  16. Pesticide residues in olive oil.

    PubMed

    Lentza-Rizos, C; Avramides, E J

    1995-01-01

    The attacks of pests and diseases and the presence of weeds make it necessary to apply pesticides to olive trees to ensure crop protection. Residues of these compounds may remain and contaminate the oil produced. For the analysis of pesticide residues in olive oil, the most common methods are multiresidue methods for fatty substrates, based on partitioning between hexane or light petroleum and acetonitrile. Recently, other methods have been applied, such as ready-to-use, disposable minicolumns or direct injection of oil into a capillary gas chromatograph equipped with a precolumn with an oil recovery tank. Although several pesticides are registered in oil-producing countries for use on olive trees, available literature on the level and fate of residues is very limited. However, it is clear that fat-soluble pesticides tend to concentrate in the oil, both after full coverage and bait spraying, and their use close to harvest should therefore be avoided. Because it is sometimes necessary to use such pesticides late in autumn because of their effectiveness in cases of severe attack, residue trials should be carried out to determine the residue concentration in oil and to set a reasonable preharvest safety interval. Data produced by such trials would permit the establishment of MRLs (tolerances) in olive oil to cover cases where the residues, although relatively high, are not of toxicological significance for consumers (risk assessment). Such is the case with corn oil and the fat-soluble insecticide methyl pirimiphos, registered in the U.S. for use on corn. The U.S. EPA tolerance for methyl pirimiphos in corn is 8 mg/kg, whereas it is 11 times higher (88 mg/kg) for corn oil because it is known to concentrate in the oil. Similar provisions for olive oil, based on data from residue trials according to Good Agricultural Practice, the long-term toxicity of each pesticide as expressed by its ADI for man, and olive oil consumption patterns, would facilitate international trade

  17. Organic Diets Significantly Lower Children’s Dietary Exposure to Organophosphorus Pesticides

    PubMed Central

    Lu, Chensheng; Toepel, Kathryn; Irish, Rene; Fenske, Richard A.; Barr, Dana B.; Bravo, Roberto

    2006-01-01

    We used a novel study design to measure dietary organophosphorus pesticide exposure in a group of 23 elementary school-age children through urinary biomonitoring. We substituted most of children’s conventional diets with organic food items for 5 consecutive days and collected two spot daily urine samples, first-morning and before-bedtime voids, throughout the 15-day study period. We found that the median urinary concentrations of the specific metabolites for malathion and chlorpyrifos decreased to the nondetect levels immediately after the introduction of organic diets and remained nondetectable until the conventional diets were reintroduced. The median concentrations for other organophosphorus pesticide metabolites were also lower in the organic diet consumption days; however, the detection of those metabolites was not frequent enough to show any statistical significance. In conclusion, we were able to demonstrate that an organic diet provides a dramatic and immediate protective effect against exposures to organophosphorus pesticides that are commonly used in agricultural production. We also concluded that these children were most likely exposed to these organophosphorus pesticides exclusively through their diet. To our knowledge, this is the first study to employ a longitudinal design with a dietary intervention to assess children’s exposure to pesticides. It provides new and persuasive evidence of the effectiveness of this intervention. PMID:16451864

  18. 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.

  19. 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...

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

    EPA Science Inventory

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

  1. 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...

  2. Airborne concentrations of organophosphorus pesticides in Korean pesticide manufacturing/formulation workplaces.

    PubMed

    Han, Don-Hee

    2011-01-01

    Pesticide manufacturing/formulation workers rather than farmers or applicators or people living with them are primarily exposed to organophosphorus pesticides (OPs). However, airborne concentrations in the workplace have rarely been determined. A total of 121 air samples (personal or area sampling) were collected at 4 factories where chlorpyrifos, EPN, parathion, and phorate, were manufactured/formulated from March through July, 2007-2008. Samples were collected by the National Institute for Occupational Safety and Health (NIOSH) method and were analyzed by GC-MS. The geometric mean (GM) level of airborne chlorpyrifos was 0.17 mg/m(3), 85% Korean Occupational Exposure Limit (KOEL) of 0.2 mg/m(3), and at 95% confidence, airborne concentrations exceeded the KOEL 58.8% of the time or less, indicating that this concentration level was unacceptable according to exposure assessment using a LogNorm2(®). However, compared with levels of TLV and/or PEL and/or WEL, the GM concentration levels of other OPs were remarkably low (range, 0.1-15.0%) and that these levels of concentrations to the other OPs were acceptable. The levels of airborne concentrations of OPs depended on isolation of the process; in other words, the levels depended on the extent to which the process was automated. The reason that the airborne concentration levels, except for those of chlorpyrifos, were very much lower than expected may be attributable to the fact that there was not exposed to 100% toxic active ingredients in pesticide formulation workplaces because of the use of supplemental agents or additives to produce complete pesticides. This study is limited since there were seldom or neither any data of previous studies to be compared with the study results nor dermal exposure data. The results were used to revise KOELs for OPs in 2010.

  3. Screening organophosphorus nerve agent degradation products in pesticide mixtures by GC-ICPMS.

    PubMed

    Richardson, Douglas D; Caruso, Joseph A

    2007-10-01

    Gas chromatography inductively coupled plasma mass spectrometry (GC-ICPMS) was utilized for the analysis of four organophosphorus nerve agent degradation products in the presence of mixtures of common organophosphorus pesticides. The first degradation products of sarin (isopropyl methylphosphonic acid, GB acid), cyclosarin (cyclohexyl methylphosphonic acid, GF acid), and soman (pinacolyl methylphosphonic acid) as well as their common final hydrolysis product methyl phosphonic acid were utilized throughout these experiments. Due to the non-volatile nature of these alkyl phosphonic acid degradation products, derivatization was performed to generate the volatile tert-butyl dimethylsilyl species. Degraded organophosphorus pesticide standards were obtained for acephate, chlorpyrifos, dichlorvos, ethion, and parathion ethyl. Mixtures consisting of three pesticides in the presence of a single nerve agent degradation product were prepared. GC-ICPMS allowed for the separation and detection of all four degradation products in the presence of pesticide mixtures in just over 12 minutes. This is the first study analyzing pesticides as interfering species for analysis of nerve agent degradation products by GC-ICPMS.

  4. Computational interaction analysis of organophosphorus pesticides with different metabolic proteins in humans

    PubMed Central

    Sharma, Amit Kumar; Gaur, Karuna; Tiwari, Rajeev Kumar; Gaur, Mulayam Singh

    2011-01-01

    Pesticides have the potential to leave harmful effects on humans, animals, other living organisms, and the environment. Several human metabolic proteins inhibited after exposure to organophosphorus pesticides absorbed through the skin, inhalation, eyes and oral mucosa, are most important targets for this interaction study. The crystal structure of five different proteins, PDBIDs: 3LII, 3NXU, 4GTU, 2XJ1 and 1YXA in Homo sapiens (H. sapiens), interact with organophosphorus pesticides at the molecular level. The 3-D structures were found to be of good quality and validated through PROCHECK, ERRAT and ProSA servers. The results show that the binding energy is maximum -45.21 relative units of cytochrome P450 protein with phosmet pesticide. In terms of H-bonding, methyl parathion and parathion with acetylcholinesterase protein, parathion, methylparathion and phosmet with protein kinase C show the highest interaction. We conclude that these organophosphorus pesticides are more toxic and inhibit enzymatic activity by interrupting the metabolic pathways in H. sapiens. PMID:23554709

  5. 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.

  6. 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.

  7. 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), ...

  8. 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.

  9. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

  11. 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).

  12. 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.

  13. 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

  14. Pesticide Residues in Food: Your Daily Dose.

    ERIC Educational Resources Information Center

    Mott, Lawrie

    1985-01-01

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

  15. 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.

  16. 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 ...

  17. 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.

  18. [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.

  19. Detection of toxic heavy metals and pesticide residue in herbal plants which are commonly used in the herbal formulations.

    PubMed

    Rao, Mruthyumjaya Meda; Kumarmeena, Ajay; Galib

    2011-10-01

    Herbal formulations are getting popular throughout the world and commercialized extensively for various medicinal properties. WHO has emphasized the need for quality assurance of herbal products, including testing of heavy metals and pesticides residues. In view of WHO guidelines, single herbal drugs used in herbal formulations were collected from local market, for testing heavy metals and persistent pesticides residue. Therefore, in the present case, we have examined few local samples of certain herbs viz. Emblica officinalis, Terminalia chebula, Terminalia belerica, and Withania somnifera. The present studies were selected for estimation of four heavy metals namely Arsenic, Cadmium, Lead, and Mercury. Apart from these, pesticide residue Viz. Organochlorine pesticides, Organophosphorus pesticides, and Pyrethroids were analyzed in the four samples of single crude drugs. Heavy metals and pesticide residue were found below detection limits in all the samples.

  20. 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.

  1. 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.

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

    PubMed

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

    2016-08-01

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

  3. Analysis of organophosphorus pesticides in whole blood by GC-MS-μECD with forensic purposes.

    PubMed

    Valente, Nuno I P; Tarelho, Sónia; Castro, André L; Silvestre, Armando; Teixeira, Helena M

    2015-07-01

    In the present work, two multi-residue methods for the determination of ten organophosphorus pesticides (OPs), namely chlorfenvinphos, chlorpyrifos, diazinon, dimethoate, fenthion, malathion, parathion, phosalone, pirimiphos-methyl and quinalphos, in post-mortem whole blood samples are presented. The adopted procedure uses GC-MS for screening and quantitation, and GC-μECD (electron capture detector) for compound confirmation. Three different Solid Phase Extraction (SPE) procedures for OPs with Oasis(®) hydrophilic lipophilic balanced (HLB) and Sep-Pak(®) C18 cartridges were tested, and followed by GC-μECD and GC-MS analysis. The Sep-Pak(®) C18 cartridges extraction procedure was selected since it generated analytical signals 5 times higher than those obtained with the two different Oasis(®) HLB cartridges extraction procedures. The method has shown to be selective for the isolation of selected OPs as well as to the chosen internal standard (ethion) in postmortem blood samples. Calibration curves between 50 and 5000 ng/mL were prepared using weighted linear regression models (1/x(2)). It was not possible to establish a working range for fenthion by GC-μECD due to the lower sensitivity of the detector to this compound, whereas for pirimiphos-methyl it was set between 500 and 5000 ng/mL. The limit of quantitation was established at 50 ng/mL for all analytes, except for pirimiphos-methyl by GC-μECD analysis (500 ng/mL). The average extraction efficiency ranged from 72 to 102%. The developed methods were considered robust and fit for the purpose, and had already been adopted in the laboratory routine analysis.

  4. Identification and quantification of pesticide residues in water samples of Dhamrai Upazila, Bangladesh

    NASA Astrophysics Data System (ADS)

    Hasanuzzaman, M.; Rahman, M. A.; Salam, M. A.

    2016-10-01

    Being agricultural country, different types of pesticides are widely used in Bangladesh to prevent the crop losses due to pest attack which are ultimately drain to the water bodies. The present study was conducted to identify and quantify the organochlorine (DDT, DDE and DDD), organophosphorus (malathion, diazinon and chloropyrifos) and carbamate (carbaryl) residues in water samples of different sources from Dhamrai upazila of Bangladesh using high performance liquid chromatography (HPLC) equipped with ultra violate (UV) detector. Thirty water samples from fish pond, cultivated land and tube-well were collected in winter season to analyze the pesticide residues. Among the organophosphorus pesticides, malathion was present in seven water samples ranging from 42.58 to 922.8 μg/L, whereas diazinon was detected in water sample-8 (WS-8) and the concentration was 31.5 μg/L. None of the tested water samples was found to be contaminated with chlorpyrifos, carbaryl or DDT and its metabolites (DDE and DDD). Except for a tube-well water sample, concentrations of the detected residues are above the acceptable limit for human body as assigned by different organizations. To avoid the possible health hazards, the indiscriminate application of pesticides should be restricted and various substitute products like bio-pesticide should be introduced in a broad scale as soon as possible.

  5. 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.

  6. Clinical analysis of penehyclidine hydrochloride combined with hemoperfusion in the treatment of acute severe organophosphorus pesticide poisoning.

    PubMed

    Liang, M J; Zhang, Y

    2015-05-11

    This study aimed to observe the clinical curative effect of penehyclidine hydrochloride (PHC) combined with hemoperfusion in treating acute severe organophosphorus pesticide poisoning. We randomly divided 61 patients with severe organophosphorus pesticide poisoning into an experimental group (N = 31) and a control group (N = 30), and we compared the coma-recovery time, mechanical ventilation time, healing time, hospital expenses, and mortality between the two groups. The coma-recovery time, mechanical ventilation time, and healing time were lower in the experimental group than in the control group (P < 0.05), while the hospitalization expenses were higher in the experimental group than in the control group (P < 0.01); moreover, no significant difference was observed in the mortality rate between the two groups. Thus, PHC combined with hemoperfusion exerts a better therapeutic effect in acute severe organophosphorus pesticide poisoning than PHC alone.

  7. [Preparation of samples for proficiency testing of pesticide residue analysis in processed foods].

    PubMed

    Okihashi, Masahiro; Osakada, Masakazu; Uchida, Kotaro; Nagayoshi, Haruna; Yamaguchi, Takahiro; Kakimoto, Kensaku; Nakayama, Yukiko; Obana, Hirotaka

    2010-01-01

    To conduct proficiency testing for the analysis of pesticide residues in processed foods, fortified samples of retort curry and pancake were examined. In the case of retort curry, heating and mixing were necessary at the time of preparation to provide a homogenous analytical sample. A mixture of 4 carbamates and 11 organophosphorus pesticides was spiked and 14 of them showed consistent results in the samples. In the case of pancake, 10 kinds of pesticides were added to the pastry. The prepared pastry was them cooked. The relative concentrations of most of the pesticides in the pancake were not affected and all the pesticides showed consistent results in the samples. These results showed that the two tested samples were suitable for proficiency testing.

  8. Probabilistic acute risk assessment of cumulative exposure to organophosphorus and carbamate pesticides from dietary vegetables and fruits in Shanghai populations.

    PubMed

    Li, Fan; Yuan, Yaqun; Meng, Pai; Wu, Min; Li, Shuguang; Chen, Bo

    2017-02-03

    Organophosphorus pesticides (OPs) and carbamate pesticides (CPs) are among the most widely used pesticides in China, playing a major role in protecting agricultural commodities. In this study, we determined the cumulative acute exposure to OPs and CPs of Shanghai residents from vegetables and fruits (VFs). The food consumption data were obtained from the Shanghai Food Consumption Survey (SHFCS) of 2012-14 including a total of 1973 participants aged 2-90 years. The pesticide residue data were obtained from the Shanghai monitoring programme during 2008-11 with 34 organophosphates and 11 carbamates analysed in a total of 5335 samples of VFs. A probabilistic approach was performed as recommended by the EFSA, using the optimistic model with non-detects set as zero and with processing factors (PFs) being used and the pessimistic model with non-detects replaced by limit of detection (LOD) and without PFs. We used the relative potency factor (RPF) method to normalise the various pesticides to the index compound (IC) of methamidophos and chlorpyrifos separately. Only in the pessimistic model using methamidophos as the IC was there was small risk of exposure exceeding the ARfD (3 µg kg(-)(1) bw day(-)(1)) in the populations of preschool children (0.029%), school-age children (0.022%) and adults (0.002%). There were no risk of exposure exceeding the ARfD of methamidophos in the optimistic model and of chlorpyrifos (100 µg kg(-)(1) bw day(-)(1)) in both optimistic and pessimistic models in all three populations. Considering the Chinese habits of overwhelmingly eating processed food (vegetables being cooked, and fruits being washed or peeled), we conclude that little acute risk was found for the exposure to VF-sourced OPs and CPs in Shanghai.

  9. 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.

  10. Albumin binding as a potential biomarker of exposure to moderately low levels of organophosphorus pesticides.

    PubMed

    Tarhoni, Mabruka H; Lister, Timothy; Ray, David E; Carter, Wayne G

    2008-06-01

    We have evaluated the potential of plasma albumin to provide a sensitive biomarker of exposure to commonly used organophosphorus pesticides in order to complement the widely used measure of acetylcholinesterase (AChE) inhibition. Rat or human plasma albumin binding by tritiated-diisopropylfluorophosphate ((3)H-DFP) was quantified by retention of albumin on glass microfibre filters. Preincubation with unlabelled pesticide in vitro or dosing of F344 rats with pesticide in vivo resulted in a reduction in subsequent albumin radiolabelling with (3)H-DFP, the decrease in which was used to quantify pesticide binding. At pesticide exposures producing approximately 30% inhibition of AChE, rat plasma albumin binding in vitro by azamethiphos (oxon), chlorfenvinphos (oxon), chlorpyrifos-oxon, diazinon-oxon and malaoxon was reduced from controls by 9+/-1%, 67+/-2%, 56+/-2%, 54+/-2% and 8+/-1%, respectively. After 1 h of incubation with 19 microM (3)H-DFP alone, the level of binding to rat or human plasma albumins reached 0.011 or 0.039 moles of DFP per mole of albumin, respectively. This level of binding could be further increased by raising the concentration of (3)H-DFP, increasing the (3)H-DFP incubation time, or by substitution of commercial albumins for native albumin. Pesticide binding to albumin was presumed covalent since it survived 24 h dialysis. After dosing rats with pirimiphos-methyl (dimethoxy) or chlorfenvinphos (oxon) (diethoxy) pesticides, the resultant albumin binding were still significant 7 days after dosing. As in vitro, dosing of rats with malathion did not result in significant albumin binding in vivo. Our results suggest albumin may be a useful additional biomonitor for moderately low-level exposures to several widely used pesticides, and that this binding differs markedly between pesticides.

  11. Determination of Pesticide Residues in Cannabis Smoke

    PubMed Central

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

    2013-01-01

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

  12. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

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

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

    PubMed

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

    2015-09-03

    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.

  15. 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

    2002-09-05

    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.

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

    EPA Science Inventory

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

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

    EPA Science Inventory

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

  18. 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 ...

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

    PubMed

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

    2016-02-01

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

  20. 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

  1. Adsorption of organophosphorus pesticides in tropical soils: The case of karst landscape of northwestern Yucatan.

    PubMed

    Alfonso, Lorenzo-Flores; Germán, Giácoman Vallejos; María Del Carmen, Ponce Caballero; Hossein, Ghoveisi

    2017-01-01

    This article discusses the adsorption of four organophosphorus pesticides-diazinon, dimethoate, methyl parathion, and sulfotep-in soil samples from four sites-Komchén, Xcanatún, Chablekal and Mocochá- in the northwest of Yucatan, Mexico. These pesticides have been detected in groundwater at concentrations greater than 5 (μg/L) during recent monitoring campaigns in the study area. In this region, groundwater contamination is exacerbated by its karst aquifer, which is susceptible to contamination and is considered very vulnerable. The experimental work was carried out using the batch equilibrium technique. Pesticide analyses by solid-phase extraction and gas chromatography were performed. The equilibrium adsorption data were analyzed by Henry, Langmuir and Freundlich models. The results indicate that the Freundlich model provides the best correlation of the experimental data. Freundlich adsorption coefficients Kf were in the range of 1.62-2.35 for sulfotep, 2.43 to 3.25 for dimethoate, from 5.54 to 9.27 for methyl parathion, and 3.22 to 5.17 for diazinon. Freundlich adsorption coefficients were normalized to the content of organic carbon in the soil to estimate the sorption coefficient of organic carbon (KOC). KOC values were in the range of 9.45-71.80, indicated that four pesticides have low adsorption on the four studied soils, which represents a high risk of contamination to the aquifer.

  2. Development of a solid-phase extraction coupling chemiluminescent enzyme immunoassay for determination of organophosphorus pesticides in environmental water samples.

    PubMed

    Xu, Zhen-Lin; Sun, Wen-Jia; Yang, Jin-Yi; Jiang, Yue-Ming; Campbell, Katrina; Shen, Yu-Dong; Lei, Hong-Tao; Zeng, Dao-Ping; Wang, Hong; Sun, Yuan-Ming

    2012-03-07

    Solid-phase extraction (SPE) and direct competitive chemiluminescence enzyme immunoassay (dcCL-EIA) were combined for the detection of organophosphorus pesticides (OPs) in environmental water samples. dcCL-EIA based on horseradish peroxidase labeled with a broad-specificity monoclonal antibody against OPs was developed, and the effects of several physicochemical parameters on dcCL-EIA performance were studied. SPE was used for the pretreatment of water samples to remove interfering substances and to concentrate the OP analytes. The coupling of SPE and dcCL-EIA can detect seven OPs (parathion, coumaphos, phoxim, quinalphos, triazophos, dichlofenthion, and azinphos-ethyl) with the limit of quantitation below 0.1 ng/mL. The recoveries of OPs from spiked water samples ranged from 62.5% to 131.7% by SPE-dcCL-EIA and 69.5% to 112.3% by SPE-HPLC-MS/MS. The screening of OP residues in real-world environmental water samples by the developed SPE-dcCL-EIA and their confirmatory analysis using SPE-HPLC-MS/MS demonstrated that the assay is ideally suited as a monitoring method for OP residues prior to chromatographic analysis.

  3. Multiwalled carbon nanotubes as solid-phase extraction materials for the gas chromatographic determination of organophosphorus pesticides in waters.

    PubMed

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

    2008-10-01

    In the present work, a GC method with nitrogen-phosphorus detection (NPD) was developed for the simultaneous determination of eight organophosphorus pesticide (OPP) residues (i.e., ethoprofos, diazinon, chlorpyrifos-methyl, fenitrothion, malathion, chlorpyrifos, fenamiphos, and buprofezin) in water samples. Preconcentration of the water samples was carried out using an SPE procedure with multiwalled carbon nanotubes (MWCNTs) of 10-15 nm od, 2-6 nm id, and 0.1-10 microm length as stationary phase. Extraction parameters, such as the amount of MWCNTs, sample volume, pH, and type and amount of the eluent were optimized. The most favorable conditions were as follows: 40 mg MWCNTs, 800 mL water, pH 6.0, and 20 mL dichloromethane, respectively. The MWCNTs-SPE-GC-NPD method was applied to the determination of these pesticides in real water samples: mineral and ground water as well as run-off water from an agricultural area collected shortly before opening out onto the sea. A recovery study was developed with five consecutive extractions of the three types of water spiked at three concentration levels (n = 15). Mean recovery values were in the range of 75-116% for mineral water (RSD < 6.3%), 67-119% for ground water (RSD < 5.8%), and 57-81% for run-off waters (RSDs < 6.9%), except for fenamiphos (mean recovery values between 40 and 84% for the three types of waters, RSDs < 8.9%). LODs were in the low ng/L level (i.e., levels below the maximum residue limits (MRLs) established by the European Union (EU) legislation for these compounds in waters). The proposed method was also applied to the analysis of six water samples (two of each type: mineral, ground, and run-off waters) in which no residues of the selected pesticides were found. Results show that the MWCNTs used in this work have a high adsorbability of the pesticides under study. The main advantage of the use of these MWCNTs is their low cost when compared with those MWCNTs previously used in the literature and with

  4. 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

  5. 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.

  6. Ecological risk of pesticide residues in the British Columbia environment: 1973-2012.

    PubMed

    Wan, Michael T

    2013-01-01

    An updated ecological risk assessment was conducted to re-evaluate and review the overall risk of pesticide residues to certain aquatic life. The focus was the impact on offsite non-target, freshwater organisms of pesticide operational sprays in British Columbia from 1973 until 2012. The values of risk quotients for pesticides of selected indicator organisms were determined to measure the effect. When compared with organophosphorus, carbamate, and other miscellaneous pesticides, this risk assessment analysis suggests that the historical use of persistent and highly toxic organochlorine pesticides posed, and continue to pose, a deleterious ecological risk. The risk is both short-term acute and long-term sub-acute, chronic toxicity to offsite, non-target aquatic invertebrates and juvenile salmonid fish. Data indicated that these organisms were, and remain, subjected to harmful effects of pesticide residues to varying degrees. Most vulnerable were, and also are, benthic organisms inhabiting bottom sediments. This substrate is the natural sink for persistent pesticide residues, predominantly organochlorine pesticides from historical use, as well as dioxins, furans, and polycyclic aromatic hydrocarbons from wood preservatives, and other sources. Environment Canada's main aquatic protection strategy was a 10 metre no-treatment buffer zone, augmented with an additional appropriate setback along shorelines of fishery and wildlife resource-sensitive water bodies. This study discusses why this guideline was necessary, useful and effective, but was only partially successful. The physical-chemical properties of pesticide residues, from either an individual compound or different compounds in combination, also influence the nature of biological impacts on non-target, aquatic organisms. Few studies have been conducted in British Columbia aquatic environments to investigate the significance of this aspect.

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

    PubMed Central

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

    1997-01-01

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

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

    PubMed

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

    2014-08-01

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

  9. Concentrations of dialkyl phosphate metabolites of organophosphorus pesticides in the U.S. population.

    PubMed Central

    Barr, Dana B; Bravo, Roberto; Weerasekera, Gayanga; Caltabiano, Lisa M; Whitehead, Ralph D; Olsson, Anders O; Caudill, Samuel P; Schober, Susan E; Pirkle, James L; Sampson, Eric J; Jackson, Richard J; Needham, Larry L

    2004-01-01

    We report population-based concentrations, stratified by age, sex, and racial/ethnic groups, of dialkyl phosphate (DAP) metabolites of multiple organophosphorus pesticides. We measured dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP), and diethyldithiophosphate (DEDTP) concentrations in 1,949 urine samples collected in U.S. residents 6-59 years of age during 1999 and 2000 as a part of the ongoing National Health and Nutrition Examination Survey (NHANES). We detected each DAP metabolite in more than 50% of the samples, with DEP being detected most frequently (71%) at a limit of detection of 0.2 microg/L. The geometric means for the metabolites detected in more than 60% of the samples were 1.85 microg/L for DMTP and 1.04 microg/L for DEP. The 95th percentiles for each metabolite were DMP, 13 microg/L; DMTP, 46 microg/L; DMDTP, 19 micro g/L; DEP, 13 microg/L; DETP, 2.2 microg/L; and DEDTP, 0.87 microg/L. We determined the molar sums of the dimethyl-containing and diethyl-containing metabolites; their geometric mean concentrations were 49.4 and 10.5 nmol/L, respectively, and their 95th percentiles were 583 and 108 nmol/L, respectively. These data are also presented as creatinine-adjusted concentrations. Multivariate analyses showed concentrations of DAPs in children 6-11 years of age that were consistently significantly higher than in adults and often higher than in adolescents. Although the concentrations between sexes and among racial/ethnic groups varied, no significant differences were observed. These data will be important in evaluating the impact of organophosphorus pesticide exposure in the U.S. population and the effectiveness of regulatory actions. PMID:14754573

  10. Impact of prechlorination on organophosphorus pesticides during drinking water treatment: Removal and transformation to toxic oxon byproducts.

    PubMed

    Li, Wei; Wu, Ruiqing; Duan, Jinming; Saint, Christopher P; van Leeuwen, John

    2016-11-15

    Prechlorination is commonly used to minimize operational problems associated with biological growth as well as taste and odor control during drinking water treatment. However, prechlorination can also oxidise micropollutants into intermediate byproducts. This could impose profound effects on the safety of the finished water if the transformed byproducts are more toxic and less removable. This study investigated the effect of prechlorination on decomposition and subsequent removal of the four organophosphorus pesticides (OPPs): chlorpyrifos, diazinon, malathion and tolclofos-methyl using a simulated conventional water treatment process of powdered activated carbon assisted coagulation-sedimentation-filtration (PAC-CSF) and postchlorination. It was found that, following prechlorination, not only did the percentage of OPPs oxidation vary significantly, but also the concentration of transformed oxons, which are more toxic than their parent compounds, increased as the major identified oxidation byproducts in water. Removal of these oxons proved to be more difficult by the PAC-CSF than their parent OPPs, because they are more water soluble and more hydrophilic. Both the OPP oxidation and oxon formation increased with chlorine dose during prechlorination. Meanwhile, the continuing chlorination of OPPs by residual free chlorine during PAC-CSF further complicated the pesticide removal processes, generally resulting in a gradually increased formation of oxons. Moreover, in the final treatment stage of postchlorination, the more chlorine-reactive pesticides, malathion and diazinon, were completely oxidised and the formation of corresponding oxons was increased with the prechlorine dose. In contrast, a certain amount of the less chlorine-reactive pesticide tolclofos-methyl still remained in solution after postchlorination, accompanied by an increased formation of tolclofos-methyl oxon with prechlorine dose. Since the oxons are resistant to further oxidation and less adsorbable

  11. Detection of pesticides residues in water samples from organic and conventional paddy fields of Ledang, Johor, Malaysia

    NASA Astrophysics Data System (ADS)

    Abdullah, Md Pauzi; Othman, Mohamed Rozali; Ishak, Anizan; Nabhan, Khitam Jaber

    2016-11-01

    Pesticides have been used extensively by the farmers in Malaysia during the last few decades. Sixteen water samples, collected from paddy fields both organic and conventional, from Ledang, Johor, were analyzed to determine the occurrence and distribution of organochlorine (OCPs) and organophosphorus (OPPs) pesticide residues. GC-ECD instrument was used to identify and determine the concentrations of these pesticide residues. Pesticide residues were detected in conventional fields in the range about 0.036-0.508 µg/L higher than detected in organic fields about 0.015-0.428 µg/L. However the level of concentration of pesticide residues in water sample from both paddy fields are in the exceed limit for human consumption, according to European Economic Commission (EEC) (Directive 98/83/EC) at 0.1 µg/L for any pesticide or 0.5 µg/L for total pesticides. The results that the organic plot is still contaminated with pesticides although pesticides were not use at all in plot possibly from historical used as well as from airborne contamination.

  12. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  13. 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...

  14. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  15. 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...

  16. 7 CFR 29.427 - Pesticide residue standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  17. Optimisation of octadecyl (C18) sorbent amount in QuEChERS analytical method for the accurate organophosphorus pesticide residues determination in low-fatty baby foods with response surface methodology.

    PubMed

    Georgakopoulos, Panagiotis; Zachari, Rodanthi; Mataragas, Marios; Athanasopoulos, Panagiotis; Drosinos, Eleftherios H; Skandamis, Panagiotis N

    2011-09-15

    Three low-fatty baby food matrices were fortified with 0.01-0.2mg/kg of phorate, diazinon, chlorpyrifos and methidathion. A "quick, easy, cheap, effective, rugged and safe" - like method (QuEChERS) was used. Quantities of octadecyl (C18) sorbent differed with fortification level and matrix fat, based on central composite experimental design. Quantification was performed by Nitrogen-Phosphorus Detector gas chromatography, using matrix-matched standards. The highest (p<0.05) recoveries were observed for methidathion, the lowest fortification levels for a specific C18 amount and the lowest C18 amounts. In meals containing vegetables (1.9% fat) and lamb (3.0% fat), 180-210mg C18 gave recoveries from 67.0% to 105.0% and absence of co-extracts. Yogurt dessert (4.5% fat) required 200-230mg C18 for similar results. Recoveries could also be predicted with <20% error by a polynomial model. The results suggest that modified QuEChERS could be effectively used in the low-fatty baby meals residue analysis.

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

    PubMed

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

    2016-06-01

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

  19. Gas chromatographic evaluation of pesticide residue contents in nectarines after non-toxic washing treatments.

    PubMed

    Pugliese, P; Moltó, J C; Damiani, P; Marín, R; Cossignani, L; Mañes, J

    2004-10-01

    Washing with aqueous solutions of citric acid, ethanol, glycerol, hydrogen peroxide, potassium permanganate, sodium metabisulfite, sodium laurylsulfate (SLS), sodium hypochlorite, and urea is evaluated for pesticide residue reduction in nectarines and compared with simple tap water washing. Residues of pesticides commonly utilized in nectarines (chlorpyrifos, fenarimol, iprodione, malathion, methidathion, myclobutanil, parathion and pirimicarb) are extracted with ethyl acetate and anhydrous sodium sulfate, extract is concentred and analyzed by GC with nitrogen-phosphorus detection. The formation of possible toxic by-products (chlorpyrifos oxon, malaoxon, methidaoxon and paraoxon methyl) is studied by GC-MS. No toxic by-products are identified in the extracts of the washed samples for the washing-time and concentrations studied, but high levels of sodium hypochlorite, hydrogen peroxide and potassium permanganate form oxons from the organophosphorus pesticides. Ethanol, glycerol and SLS solutions removed near the 50% of the pesticide residues. The other solutions were not more effective than tap water washing. The amount of pesticide removed by washings is related to its water solubility and octanol-water partition coefficient.

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

    SciTech Connect

    Porte, R.E.

    1995-12-01

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

  1. 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.

  2. 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.

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

    PubMed

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

    2009-02-01

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

  4. Biosensors and their applications in detection of organophosphorus pesticides in the environment.

    PubMed

    Hassani, Shokoufeh; Momtaz, Saeideh; Vakhshiteh, Faezeh; Maghsoudi, Armin Salek; Ganjali, Mohammad Reza; Norouzi, Parviz; Abdollahi, Mohammad

    2017-01-01

    This review discusses the past and recent advancements of biosensors focusing on detection of organophosphorus pesticides (OPs) due to their exceptional use during the last decades. Apart from agricultural benefits, OPs also impose adverse toxicological effects on animal and human population. Conventional approaches such as chromatographic techniques used for pesticide detection are associated with several limitations. A biosensor technology is unique due to the detection sensitivity, selectivity, remarkable performance capabilities, simplicity and on-site operation, fabrication and incorporation with nanomaterials. This study also provided specifications of the most OPs biosensors reported until today based on their transducer system. In addition, we highlighted the application of advanced complementary materials and analysis techniques in OPs detection systems. The availability of these new materials associated with new sensing techniques has led to introduction of easy-to-use analytical tools of high sensitivity and specificity in the design and construction of OPs biosensors. In this review, we elaborated the achievements in sensing systems concerning innovative nanomaterials and analytical techniques with emphasis on OPs.

  5. Development of dispersive liquid-liquid microextraction method for the analysis of organophosphorus pesticides in tea.

    PubMed

    Moinfar, Soleyman; Hosseini, Mohammad-Reza Milani

    2009-09-30

    In this article, a new method for the determination of organophosphorus pesticides (OPPs) in tea was developed by using dispersive liquid-liquid microextraction (DLLME) and gas chromatography-flame photometric detection (GC-FPD). A mixture of acetonitrile and n-hexane was used as an extraction solvent for the extraction of OPPs from tea samples. When the extraction process was finished, the mixture of solvents was rapidly dispersed in water; target analyte was extracted to a small volume of n-hexane, using DLLME. Recovery tests were performed for concentration 5.0 microg/kg. The recovery for each target analyte was in the range between 83.3 and 117.4%. The repeatability of the proposed method, expressed as relative standard deviation, varied between 3 and 7.8% (n=3). The detection limit of the method for tea was found ranging from 0.030 to 1 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 has high-enrichment factors and low consumption of organic solvent.

  6. 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.

  7. Determination of organophosphorus pesticides by gas chromatography with mass spectrometry using a large-volume injection technique after magnetic extraction.

    PubMed

    Nedaei, Maryam; Salehpour, Ali-Reza; Mozaffari, Shahla; Yousefi, Seyedeh Mahboobeh; Yousefi, Seyed Reza

    2014-09-01

    A fast and efficient method was developed for the extraction and determination of organophosphorus pesticides in water samples. Organophosphorus pesticides were extracted by solid-phase extraction using magnetic multi-walled carbon nanotubes and determined by gas chromatography with ion-trap mass spectrometry. Parameters affecting the extraction were investigated. Under optimum conditions of the method, 10 mg magnetic multi-walled carbon nanotubes were added into 10 mL sample. After 2 min, adsorbent particles settled at the bottom of test tube with a magnet. After removing aqueous supernatant, the analytes were desorbed with acetonitrile. Then, 70 μL of acetonitrile phase was injected into the gas chromatography and mass spectrometry system that had an ion-trap analyzer. To achieve high sensitivity, the large-volume-injection technique was used with a programmed temperature vaporization inlet, and the ion-trap mass spectrometer was operated in single ion storage mode. Under the best conditions, the enrichment factors and extraction recoveries were in the range of 113-124 and 74-103%, respectively. The limits of detection were between 3 and 15 ng/L, and the relative standard deviations were < 10%. This method was successfully used for the determination of organophosphorus pesticides in dam water, lagoon water, and river water samples with good reproducibility and recovery.

  8. 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

  9. 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

    2016-02-03

    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.

  10. Pesticide residue levels in Argentinian pasteurised milk.

    PubMed

    Maitre, M I; de la Sierra, P; Lenardon, A; Enrique, S; Marino, F

    1994-10-14

    Pasteurised milk--120 samples--was analysed (in Santa Fe City, Argentina) to determine organochlorinated pesticides. Almost all samples showed the presence of such residues; the compounds more frequently detected being: heptachlor and its epoxide (98%) and hexachlorocyclohexane .HCH. alpha and gamma isomers. Residues of aldrin and dieldrin; chlordane (alpha and gamma); endosulfan (I and II); DDT (o,p-DDT, p,p'-DDE, o,p-DDD, p,p'-DDD) as well as hexachlorocyclobenzene (HCB) were also found. Despite their presence high concentrations are sporadic, the mean values being less than FAO/OMS tolerance limits. Relations between maxima concentrations and seasons were not found.

  11. Dissipation kinetics of organophosphorus pesticides in milled toasted maize and wheat flour (gofio) during storage.

    PubMed

    González-Curbelo, Miguel Ángel; Socas-Rodríguez, Bárbara; Herrero, Miguel; Herrera-Herrera, Antonio V; Hernández-Borges, Javier

    2017-08-15

    The dissipation/degradation of the pesticides dimethoate, terbufos, disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (disulfoton sulfoxide, terbufos sulfone and disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (disulfoton) for maize gofio and between 69% (terbufos) and 92% (disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.

  12. 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

  13. In vitro kinetic interactions of DEET, pyridostigmine and organophosphorus pesticides with human cholinesterases.

    PubMed

    Wille, Timo; Thiermann, Horst; Worek, Franz

    2011-04-25

    The simultaneous use of the repellent DEET, pyridostigmine, and organophosphorus pesticides has been assumed as a potential cause for the Gulf War Illness and combinations have been tested in different animal models. However, human in vitro data on interactions of DEET with other compounds are scarce and provoked the present in vitro study scrutinizing the interactions of DEET, pyridostigmine and pesticides with human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE). DEET showed to be a weak and reversible inhibitor of hAChE and hBChE. The IC(50) of DEET was calculated to be 21.7mM DEET for hAChE and 3.2mM DEET for hBChE. The determination of the inhibition kinetics of pyridostigmine, malaoxon and chlorpyrifos oxon with hAChE in the presence of 5mM DEET resulted in a moderate reduction of the inhibition rate constant k(i). The decarbamoylation velocity of pyridostigmine-inhibited hAChE was not affected by DEET. In conclusion, the in vitro investigation of interactions between human cholinesterases, DEET, pyridostigmine, malaoxon and chlorpyrifos oxon showed a weak inhibition of hAChE and hBChE by DEET. The inhibitory potency of the tested cholinesterase inhibitors was not enhanced by DEET and it did not affect the regeneration velocity of pyridostigmine-inhibited AChE. Hence, this in vitro study does not give any evidence of a synergistic effect of the tested compounds on human cholinesterases.

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

    PubMed Central

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

    2003-01-01

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

  15. 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.

  16. Enzyme-linked immunosorbent assay for the determination of five organophosphorus pesticides in camellia oil.

    PubMed

    Liu, Yihua; Guo, Yirong; Zhu, Guonian; Tang, Fubin

    2014-07-01

    A matrix solid-phase dispersion and direct competitive enzyme-linked immunosorbent assay (MSPD-ELISA) was developed for five organophosphorus pesticides (OPs) in camellia oil. Seven haptens with different substituents in the aromatic ring were used to prepare different competitors; the ELISA showed highest sensitivity and specificity to OPs when the competitor had moderate heterology to the immunizing hapten. Several assay conditions were optimized to increase the ELISA sensitivity. The optimized ELISA for five OPs had 50% inhibitory concentrations of 6.3 ng/ml (parathion), 18.9 ng/ml (methyl parathion), 120.7 ng/ml (fenitrothion), 110.4 ng/ml (fenthion), and 20.7 ng/ml (phoxim). The average recoveries of five OPs in camellia oil ranged from 75.7 to 105.3%, with the interassay coefficient of variations ranging from 6.0 to 13.4%. Compared with the results previously reported, the ELISA that was developed in the present study showed a much higher sensitivity. Additionally, MSPD was used in the sample preparation to minimize the matrix effect. Recoveries from the method developed here were in agreement with those obtained by gas chromatography, which indicated that the detection performance of the MSPD-ELISA could meet the regulatory requirements of different governments and international organizations.

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

    PubMed

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

    2013-01-02

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

  18. 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

  19. Evaluation of pesticide residues in fruits and vegetables from Algeria.

    PubMed

    Mebdoua, Samira; Lazali, Mohamed; Ounane, Sidi Mohamed; Tellah, Sihem; Nabi, Fahima; Ounane, Ghania

    2017-06-01

    A total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and import were analysed to detect the presence of pesticide residues. Analysis was performed by multi-residual extraction followed by gas chromatography-mass spectrometry. In 42.5% of the tested samples, no residues were found and 12.5% of samples contained pesticide residues above maximum residue limits. Risk assessment for long-term exposure was done for all pesticides detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment revealed that in seven pesticide/commodity combinations, including three pesticides (chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded.

  20. Distribution, fate and effects of pesticide residues in tropical coastal lagoons of northwestern Mexico.

    PubMed

    Carvalho, F P; Gonzalez-Farias, F; Villeneuve, J P; Cattini, C; Hernandez-Garza, M; Mee, L D; Fowler, S W

    2002-11-01

    Analyses of pesticide residues in sediments, water and biota of the Altata-Ensenada del Pabellon coastal lagoon system in Sinaloa, Mexico, showed the presence of organochlorine and organophosphorus compounds. For all the compounds analysed, concentrations in sediments were higher near the points of water discharge from ponds and drainage from the agricultural area. Among the organochlorines, total DDTs displayed the largest sedimentary reservoir, followed by total endosulfans and chlorpyrifos. In sediments, as well as in biota, pp'-DDT concentrations were lower than those of DDT metabolites, which confirms the reduction in the previous massive use of this compound in agriculture. Endosulfan is currently used in the region and endosulfan residues in lagoon sediments attained levels considered to be toxic to meiofauna, therefore constituting an ecological risk to lagoon ecosystems. There was a large sedimentary reservoir of chlorpyrifos but its ecotoxicological risk is difficult to assess due to lack of adequate comparative data. Nevertheless, concentrations of chlorpyrifos which approach acute toxic levels for shrimp were recorded in lagoon water. This suggests that drainage from agricultural fields during high runoff may, on occasion, cause mass mortality of shrimp and fish Organophosphorus pesticides are widely regarded to degrade very rapidly in aquatic systems. Experimental research performed with 14C-labelled chlorpyrifos and parathion has shown that they may be stabilised for relatively long periods of time through sediment-water partitioning. This extension of their environmental half-lives increases their potential for impacting on coastal ecosystems. Since organophosphorus pesticides are highly toxic for aquatic organisms at concentrations generally lower than organochlorines, their presence in the lagoon water and sediment is a matter for much concern. The increased use of tropical coastal lagoons for shrimp and fish farming requires the implementation of

  1. 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

    2012-07-03

    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.

  2. A natural matrix (pureed tomato) candidate reference material containing residue concentrations of pesticide chemicals.

    PubMed

    Armishaw, P; Millar, R

    2001-06-01

    NARL (the Australian National Analytical Reference Laboratory) is preparing a pureed tomato reference material spiked with residue concentrations of a range of pesticide chemicals relevant to the Australian horticultural industry. Traceable certified pesticide concentration values will be established using both isotope dilution mass spectrometry primary methods (developed within NARL) and measurements carried out by a number of experienced laboratories. As far as we are aware, there is no other similar CRM available anywhere in the world. The need for such a material is evident from the results of interlaboratory proficiency studies conducted by NARL among Australian and Asia-Pacific residue testing laboratories. Many participants are experiencing difficulties with the analysis of pesticide residues in fruit and vegetables at concentrations of regulatory significance. Chemicals such as methamidophos (an organophosphorus pesticide widely used on tomato crops) are causing particular problems. In a pilot study, a number of units of control (unspiked tomato) and the candidate reference material were prepared and packaged into lacquered steel cans which were sealed and sterilised by immersion in boiling water. Accelerated stability testing of the packaged material was conducted using isochronous measurement. All of the pesticides showed some degree of degradation after 4 weeks of storage at 50 degrees C, and after 168 days of storage at room temperature. However, all appeared to be stable after 168 days of freezer storage. Homogeneity testing involved duplicate test portions taken from every 50th unit of reference material. An experimental protocol was devised with the aim of minimising the analytical variability and assuring the quality of the data generated. There is some degree of inhomogeneity in the prepared material and a small fill trend is also indicated. Potential improvements to the spiking and preparation procedure have been identified and it is planned to

  3. Extraction and preconcentration of organophosphorus pesticides in water by using a polymethacrylate-based sorbent modified with magnetic nanoparticles.

    PubMed

    Meseguer-Lloret, Susana; Torres-Cartas, Sagrario; Catalá-Icardo, Mónica; Simó-Alfonso, Ernesto F; Herrero-Martínez, José M

    2017-03-14

    A polymethacrylate-based sorbent modified with magnetic nanoparticles (MNPs) has been synthesized and used as sorbent for solid-phase extraction (SPE) and magnetic solid-phase extraction (MSPE) of three organophosphorus pesticides (phosmet, pirimiphos-methyl, and chlorpyrifos) in water samples followed by high-performance liquid chromatography-diode array detection. The sorbent was prepared from a glycidyl methacrylate-based polymer, modified with a silanizing agent, followed by immobilization of MNPs on the surface of the material. The sorbent was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Comparative studies of this support were done both in conventional SPE cartridge and MSPE approach. Several extraction parameters (loading pH, elution solvent, eluting volume, and loading flow rate) were investigated in detail. Under optimal conditions, the proposed sorbent gave an excellent enrichment efficiency of analytes and detection limits between 0.01 and 0.25 μg L(-1). The recoveries of organophosphorus pesticides in spiked water samples were in the range of 71-98%, and the developed sorbent showed a high reusability (up to 50 uses without losses in recovery). The proposed method was satisfactorily applied to the analysis of these pesticides in water samples from different sources.

  4. 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.

  5. Pesticide and plasticizer residues in bergamot essential oils from Calabria (Italy).

    PubMed

    Di Bella, Giuseppa; Saitta, Marcello; La Pera, Lara; Alfa, Maria; Dugo, Giacomo

    2004-08-01

    Organophosphorus and organochlorine pesticides, phosphorated plasticizers, chloroparaffins and phthalate esters contamination in bergamot essential oils produced in Calabria in the crop years 1999-2000 was studied by HRGC in connection with detectors FPD, ECD, MS. Residues of dicofol and tetradifon were found in oils from both crop years. The mean dicofol concentration was 0.26 mg/l in samples from 1999 and 0.20 mg/l in those from 2000; the mean tetradifon content was 0.06 mg/l for both the crop years. Among plasticizers, residues of diisobutyl phthalate, di-n-butyl phthalate, and bis(2-ethylhexyl) phthalate were found in samples from crop years 1999 and 2000, the mean content were 1.22 and 1.23 mg/l, 1.51 and 1.65 mg/l, 1.38 and 1.42 mg/l respectively.

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

    PubMed

    Costa, M J; Ribeiro, L R; Salla, R F; Gamero, F U; Alves, L M L M; Silva-Zacarin, E C M

    2015-11-01

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

  7. [Rapid Detection of Trace Dimethoate Pesticide Residues Based on Colorimetric Spectroscopy].

    PubMed

    Li, Wen; Sun, Ming; Li, Min-zan; Sun, Hong

    2015-07-01

    In order to detect dimethoate pesticide residues rapidly and safely, a feasible method based on colorimetric spectroscopy was developed. Because dimethoate is one of organophosphorus pesticides containing sulfur, its sulfenyl can react with Pd2+ to produce a yellow complex named palladium sulfide. PdCl2 was used as the color agent, which was dissolved in acetic acid instead of the common concentrated hydrochloric acid. The dimethoate solution was prepared by dissolving the commercial pesticides into distilled water at different concentrations. The pesticide samples were reacted with the same amount of PdC2 solution respectively. The absorbance spectra of the samples after coloring reaction were measured in the region of 300-900 nm by a spectrophotometer. The result showed that the effect of using acetic acid instead of concentrated hydrochloric acid was not only safe but also preferable, and 0.5 mg x kg(-1) was the minimum concentration of the pesticide that could be distinguished in the spectra. The result met the pesticide residue detecting requirements of part fruits and vegetables in the national standard GB2763-2012 regulations. Further studies on random 40 dimethoate samples from 0.5 to 88 mg x kg(-1) were carried out. Thirty samples were randomly selected to establish the training model and remaining 10 samples were used to test the model. The preprocessing methods were carried on the spectrum data such as normalization and smoothing to get a better effect through comparison their prediction results with the correlation coefficient (r) and the root mean square error of cross-validation (RMSEP). The principal component analysis (PCA) method and partial least squares (PLS) method were used to establish prediction models respectively in the different wave ranges. By calculating the correlation coefficient of dimethoate samples in 350-900 nm the maximum of 0.9572 was obtained at wavelength 458 nm, so 453-463 and 400-600 nm were selected as feather regions

  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. 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

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

    PubMed Central

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

    2012-01-01

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

  11. 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.

  12. Biologic monitoring of exposure to organophosphorus pesticides in 195 Italian children.

    PubMed

    Aprea, C; Strambi, M; Novelli, M T; Lunghini, L; Bozzi, N

    2000-06-01

    One hundred ninety-five 6- to 7-year-old children who lived in the municipality of Siena (Tuscany, Italy), underwent biologic monitoring to evaluate urinary excretion of several alkylphosphates that are metabolites of organophosphorus pesticides. We evaluated dimethylphosphate (DMP), dimethylthiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP), and diethyldithiophosphate (DEDTP). We obtained urine samples taken in the children's schools, and each sample was accompanied by a questionnaire about lifestyle and dietary habits. We found DMP and DMTP in detectable concentrations in the greatest number of samples (96 and 94%, respectively). The DMP values were geometric mean (GM) 116.7, [geometric standard deviation (GSD) 2.5], and a range of 7.4-1,471.5 nmol/g creatinine. The corresponding DMTP values were GM 104.3 (GSD 2.8) and a range of 4.0-1,526.0 nmol/g creatinine. DMDTP, DEP, DETP, and DEDTP concentrations were GM 14.1, (GSD 3.0), and a range of 3.3-754.6 nmol/g creatinine in 34% of the children; GM 33.2, (GSD 2.4), and a range of 5.1-360.1 nmol/g creatinine in 75% of the children; GM 16.0, (GSD 2.9), and a range of 3.1-284.7 in 48% of the children; and GM 7.7, (GSD 2.1), and a range of 2.3-140.1 in 12% of the children, respectively. The significant variable for urinary excretion of these metabolites in children was pest control operations performed inside or outside the house in the preceding month; however, the presence of a vegetable garden near the house rarely emerged. The urinary excretion of alkylphosphates in children was significantly higher than in a group of the adult population resident in the same province.

  13. Novel sol-gel hybrid methyltrimethoxysilane-tetraethoxysilane as solid phase extraction sorbent for organophosphorus pesticides.

    PubMed

    Wan Ibrahim, Wan Aini; Veloo, Krishna Veni; Sanagi, Mohd Marsin

    2012-03-16

    A novel sol-gel hybrid methyltrimethoxysilane-tetraethoxysilane (MTMOS-TEOS) was produced and applied as sorbent for solid phase extraction (SPE). Five selected organophosphorus pesticides (OPPs) were employed as model compounds to evaluate the extraction performance of the synthesized sol-gel organic-inorganic hybrid MTMOS-TEOS. Analysis was performed using gas chromatography-mass spectrometry. Several important SPE parameters were optimized. Under the optimum extraction conditions, the method using the sol-gel organic-inorganic hybrid MTMOS-TEOS as SPE sorbent showed good linearity in the range of 0.001-1 μg L(-1), good repeatability (RSD 2.1-3.1%, n=5), low limits of detection at S/N=3 (0.5-0.9 pg mL(-1)) and limit of quantification (1-3 pg mL(-1), S/N=10). The performance of the MTMOS-TEOS SPE was compared to commercial C18 Supelclean SPE since C18 SPE is widely used for OPPs. The MTMOS-TEOS SPE method LOD was 500-600 × lower than the LOD of commercial C18 SPE. The LOD achieved with the sol-gel organic-inorganic hybrid MTMOS-TEOS SPE sorbent allowed the detection of these OPPs in drinking water well below the level set by European Union (EU) at 0.1 μg L(-1) of each pesticides. The developed MTMOS-TEOS SPE method was successfully applied to real sample analysis of the selected OPPs from several water samples and its application extended to the analysis of several fruits samples. Excellent recoveries and RSDs of the OPPs were obtained from the various water samples (recoveries: 97-111%, RSDs 0.4-2.8%, n=3) and fruit samples (recoveries: 96-111%), RSDs 1-4%, n=5) using the sol-gel organic-inorganic hybrid MTMOS-TEOS SPE sorbent. Recoveries and RSDs of OPPs from river water samples and fruit samples using C18 Supelclean SPE sorbent were 91-97%, RSD 0.9-2.6, n=3 and 86-96%, RSD 3-8%, n=5, respectively). The novel sol-gel hybrid MTMOS-TEOS SPE sorbent demonstrate the potential as an alternative inexpensive extraction sorbent for OPPs with higher sensitivity for

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

    PubMed

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

    2008-11-21

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

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

    PubMed Central

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

    2011-01-01

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

  16. 76 FR 69692 - Withdrawal of a Pesticide Petition for Residues of Pesticide Chemicals in or on Various Commodities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... AGENCY 40 CFR Part 180 Withdrawal of a Pesticide Petition for Residues of Pesticide Chemicals in or on... establishment or modification of regulations for residues of pesticide chemicals in or on various commodities... regulations in 40 CFR part 174 or part 180 for residues of pesticide chemicals in or on various...

  17. Development and comparative study of chemosynthesized antigen and mimotope-based immunoassays for class-specific analysis of O,O-dimethyl organophosphorus pesticides

    PubMed Central

    Zhao, Fengchun; Wang, Huimin; Han, Xiao; Yang, Zhengyou

    2016-01-01

    The multi-residue determination of organophosphorus pesticides (OPs) is an important task due to the wide application and high toxicity of OPs. However, there is no promising immunoassay to monitor the multi-residue of O,O-dimethyl OPs. In this study, a monoclonal antibody (mAb) against a generic hapten of O,O-dimethyl OPs (O,O-dimethyl O-(3-carboxyphenyl)phosphorothioate) was prepared. To develop an effective class-specific immunoassay, two strategies were performed to select the appropriate coating antigen or competing antigen. On the one hand, a total of 20 haptens were chemosynthesized, attached to ovalbumin for use as coating antigen candidates, and selected by direct competitive ELISA (dcELISA). As a second strategy, mimotopes of the mAb were selected from a random phage-display peptide library by panning, and the optimum mimotope was expressed as a fusion protein and biotinylated in vitro. Based on the selected chemosynthesized coating antigen and the biotinylated mimotope fusion protein, two sensitive broad-specificity dcELISAs were developed. The sensitivity, selectivity and practicability of the two immunoassays were compared. The results demonstrated that both methods showed similar selectivity and sensitivity and were reliable for O,O-dimethyl OP residues screening. However, the screening operation of mimotopes was much simpler and safer compared to the preparation of chemosynthesized coating antigens. PMID:27874102

  18. Combination of dispersive solid-phase extraction and salting-out homogeneous liquid-liquid extraction for the determination of organophosphorus pesticides in cereal grains.

    PubMed

    Jia, Chunhong; Zhu, Xiaodan; Wang, Jihua; Zhao, Ercheng; He, Min; Chen, Li; Yu, Pingzhong

    2014-07-01

    A new analytical method for the determination of organophosphorus pesticides in cereal samples was developed by combining dispersive SPE (d-SPE) and salting-out homogeneous liquid-liquid extraction (SHLLE). The pesticides were first extracted from cereal grains with acetonitrile, followed by d-SPE cleanup. A 2 mL aliquot of the extract was then added to a centrifuge tube containing 9.2 mL water and 3.3 g NaCl for SHLLE. Analysis of the extract was carried out by gas chromatography coupled with flame photometric detection. The d-SPE procedure effectively provides the necessary cleanup of the extract while SHLLE is used as an efficient concentration technique. Experimental parameters influencing the extraction efficiency including amounts of added water and salt were investigated. Recovery studies were carried out at three fortification levels, yielding recoveries in the range of 57.7-98.1% with the RSD from 3.7 to 10.9%. The reported limits of determination obtained from this study were 1 μg/kg, which is better than the conventional methods. In the analysis of 40 wheat and corn samples taken from Beijing suburbs, only two wheat samples have chlorpyrifos residue over the limits of determination.

  19. 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...

  20. 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.

  1. 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.

  2. 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

    2014-09-05

    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.

  3. Detectable organophosphorus pesticide exposure in the blood of Nebraska and Iowa residents measured by mass spectrometry of butyrylcholinesterase adducts.

    PubMed

    Jiang, Wei; Lockridge, Oksana

    2013-03-25

    The Centers for Disease Control and Prevention detected organophosphorus pesticide (OP) metabolites in the urine of 96% of Americans, for urine collected before the ban on nonagricultural use of OP in December 2001. It was not known whether exposure was to OP degradation products or to live OP. Our goal was to determine whether exposure was to live OP in the years 2001, 2003, and 2005. Our test for exposure was the presence of OP adducts on plasma butyrylcholinesterase (BChE) detected by mass spectrometry. We purified three lots of BChE from the pooled plasma of 600-800 individuals each, in the years 2001, 2003, and 2005. Blood donors were healthy adults living in Nebraska and Iowa, two agricultural states that grow corn and soybeans. The purified BChE was tested for the presence of OP adducts on serine 198 using MALDI-TOF/TOF mass spectrometry. Low levels of methoxyphosphate-labeled BChE were found. The amount of adducted BChE was highest (1%) in blood collected in the year 2001 and lowest (0.2%) in blood collected in the year 2005. A negative control sample of BChE purified from cord blood collected in the year 2012 had no detectable adducts. It was concluded that Nebraska and Iowa residents were exposed to very low levels of live, intact organophosphorus pesticides, and that exposure levels in the pooled samples declined after the year 2001.

  4. 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...

  5. 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...

  6. 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...

  7. Extraction and determination of organophosphorus pesticides in water samples by a new liquid phase microextraction-gas chromatography-flame photometric detection.

    PubMed

    Khalili-Zanjani, Mohammad Reza; Yamini, Yadollah; Yazdanfar, Najmeh; Shariati, Shahab

    2008-01-14

    A rapid, sensitive and efficient liquid phase microextraction (LPME) method was developed to determine trace concentrations of some organophosphorus pesticides in water samples. This method combines liquid phase microextraction with gas chromatographic (GC) analysis in a simple and inexpensive apparatus involving very little organic solvent consumption. It involves exposing a floated drop of an organic solvent on the surface of aqueous solution in a sealed vial. Experimental parameters which control the performance of LPME such as type of organic solvent, organic solvent and sample volumes, sample stirring rate, sample solution temperature, salt addition and exposure time were investigated and optimized. Finally, the enrichment factor, dynamic linear range (DLR), limit of detection (LOD) and precision of the method were evaluated by the water samples spiked with organophosphorus pesticides. Using optimum extraction conditions, very low detection limits (0.01-0.04mugL(-1)) and good linearities (0.9983organophosphorus pesticides in different types of natural water samples and acceptable recoveries (96-104%) and precisions (3.5organophosphorus pesticides in water samples.

  8. Assessment of the residual toxicity to Anopheles gambiae of the organophosphorus insecticides malathion and Baytex

    PubMed Central

    Smith, A.; Hocking, K. S.

    1962-01-01

    As part of a WHO programme to evaluate possible substitutes for the chlorinated hydrocarbons to which anopheline mosquitos in many countries have become resistant, two organophosphorus insecticides, malathion and Baytex, were tested as residual sprays on various types of surface against Anopheles gambiae adults in experimental huts at Magugu in Tanganyika. The long-lasting toxicity of both insecticides on relatively impervious surfaces was confirmed, but—as is the case with the chlorinated hydrocarbons—shorter persistence was obtained on sorptive surfaces. As most of the mosquitos rested on the roof, its surface was of much greater importance than the wall surface in determining kill; trials with naturally entering mosquitos indicated that where the roof was of grass malathion was to be preferred to Baytex. Observations confirmed that control huts attracted far more mosquitos than the treated huts and that the insecticide vapour apparently masked the human odour. PMID:13993107

  9. Simultaneous determination of nine trace organophosphorous pesticide residues in fruit samples using molecularly imprinted matrix solid-phase dispersion followed by gas chromatography.

    PubMed

    Wang, Xilong; Qiao, Xuguang; Ma, Yue; Zhao, Tao; Xu, Zhixiang

    2013-04-24

    How to determine trace multipesticide residues in fruits is an important problem. This paper reports a molecularly imprinted polymer (MIP) that was prepared using 4-(dimethoxyphosphorothioylamino)butanoic acid as the template, acrylamide as the functional monomer, and ethylene glycol dimethacrylate (EGDMA) as the cross-linker. The novel imprinted polymer was characterized by static and kinetic adsorption experiments, and it exhibited good recognition ability and fast adsorption-desorption dynamicd toward trichlorfon, malathion, acephate, methamidophos, omethoate, dimethoate, phosphamidon, monocrotophos, and methyl parathion. Using this imprinted polymer as sorbent, matrix solid-phase dispersion coupled to gas chromatography for simultaneous determination of nine trace organophosphorus pesticide residues was first presented. Under the optimized conditions, the LOD (S/N = 3) of this method for the nine organophosphorus was 0.3-1.6 μg kg(-1); the RSD for three replicate extractions ranged from 1.2 to 4.8%. The apple and pear samples spiked with nine organophosphate pesticides at levels of 20 and 100 μg kg(-1) were determined according to this method with good recoveries ranging from 81 to 105%. Moreover, this developed method was successfully applied to the quantitative detection of the nine organophosphorus pesticide residues in orange samples.

  10. Human hepatic cytochrome P450-specific metabolism of the organophosphorus pesticides methyl parathion and diazinon.

    PubMed

    Ellison, Corie A; Tian, Yuan; Knaak, James B; Kostyniak, Paul J; Olson, James R

    2012-01-01

    Organophosphorus pesticides (OPs) are a public health concern due to their worldwide use and documented human exposures. Phosphorothioate OPs are metabolized by cytochrome P450s (P450s) through either a dearylation reaction to form an inactive metabolite, or through a desulfuration reaction to form an active oxon metabolite, which is a potent cholinesterase inhibitor. This study investigated the rate of desulfuration (activation) and dearylation (detoxification) of methyl parathion and diazinon in human liver microsomes. In addition, recombinant human P450s were used to determine the P450-specific kinetic parameters (K(m) and V(max)) for each compound for future use in refining human physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models of OP exposure. The primary enzymes involved in bioactivation of methyl parathion were CYP2B6 (K(m) = 1.25 μM; V(max) = 9.78 nmol · min(-1) · nmol P450(-1)), CYP2C19 (K(m) = 1.03 μM; V(max) = 4.67 nmol · min(-1) · nmol P450(-1)), and CYP1A2 (K(m) = 1.96 μM; V(max) = 5.14 nmol · min(-1) · nmol P450(-1)), and the bioactivation of diazinon was mediated primarily by CYP1A1 (K(m) = 3.05 μM; V(max) = 2.35 nmol · min(-1) · nmol P450(-1)), CYP2C19 (K(m) = 7.74 μM; V(max) = 4.14 nmol · min(-1) · nmol P450(-1)), and CYP2B6 (K(m) = 14.83 μM; V(max) = 5.44 nmol · min(-1) · nmol P450(-1)). P450-mediated detoxification of methyl parathion only occurred to a limited extent with CYP1A2 (K(m) = 16.8 μM; V(max) = 1.38 nmol · min(-1) · nmol P450(-1)) and 3A4 (K(m) = 104 μM; V(max) = 5.15 nmol · min(-1) · nmol P450(-1)), whereas the major enzyme involved in diazinon detoxification was CYP2C19 (K(m) = 5.04 μM; V(max) = 5.58 nmol · min(-1) · nmol P450(-1)). The OP- and P450-specific kinetic values will be helpful for future use in refining human PBPK/PD models of OP exposure.

  11. Human Hepatic Cytochrome P450-Specific Metabolism of the Organophosphorus Pesticides Methyl Parathion and Diazinon

    PubMed Central

    Tian, Yuan; Knaak, James B.; Kostyniak, Paul J.; Olson, James R.

    2012-01-01

    Organophosphorus pesticides (OPs) are a public health concern due to their worldwide use and documented human exposures. Phosphorothioate OPs are metabolized by cytochrome P450s (P450s) through either a dearylation reaction to form an inactive metabolite, or through a desulfuration reaction to form an active oxon metabolite, which is a potent cholinesterase inhibitor. This study investigated the rate of desulfuration (activation) and dearylation (detoxification) of methyl parathion and diazinon in human liver microsomes. In addition, recombinant human P450s were used to determine the P450-specific kinetic parameters (Km and Vmax) for each compound for future use in refining human physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models of OP exposure. The primary enzymes involved in bioactivation of methyl parathion were CYP2B6 (Km = 1.25 μM; Vmax = 9.78 nmol · min−1 · nmol P450−1), CYP2C19 (Km = 1.03 μM; Vmax = 4.67 nmol · min−1 · nmol P450−1), and CYP1A2 (Km = 1.96 μM; Vmax = 5.14 nmol · min−1 · nmol P450−1), and the bioactivation of diazinon was mediated primarily by CYP1A1 (Km = 3.05 μM; Vmax = 2.35 nmol · min−1 · nmol P450−1), CYP2C19 (Km = 7.74 μM; Vmax = 4.14 nmol · min−1 · nmol P450−1), and CYP2B6 (Km = 14.83 μM; Vmax = 5.44 nmol · min−1 · nmol P450−1). P450-mediated detoxification of methyl parathion only occurred to a limited extent with CYP1A2 (Km = 16.8 μM; Vmax = 1.38 nmol · min−1 · nmol P450−1) and 3A4 (Km = 104 μM; Vmax = 5.15 nmol · min−1 · nmol P450−1), whereas the major enzyme involved in diazinon detoxification was CYP2C19 (Km = 5.04 μM; Vmax = 5.58 nmol · min−1 · nmol P450−1). The OP- and P450-specific kinetic values will be helpful for future use in refining human PBPK/PD models of OP exposure. PMID:21969518

  12. [Determination of organophosphorous pesticide residues in red wine by solid phase microextraction-gas chromatography].

    PubMed

    Hu, Yuan; Liu, Wenmin; Zhou, Yanming; Guan, Yafeng

    2006-05-01

    A method for the determination of 12 organophosphorus pesticide residues (OPs) in red wine by fiber solid phase microextraction (SPME) coupled with gas chromatography (GC) was developed and validated. The SPME phase was prepared by sol-gel technology of physical incorporation. The extraction conditions were optimized with the results of stirring rate of 1,250 r/min, NaCl mass concentration of 150 g/L, and extraction time of 30 min. With the sample volume of 25 mL, the relative standard deviations (RSD) of peak areas for most of OPs were below 5%, and the detection limits of OPs were in the range of 5 ng/L-0.38 microg/L. It can be seen from the results that this method has the potential to analyze OPs in other beverages and soft drinking materials.

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

    PubMed

    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

    2012-08-01

    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.

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

    PubMed

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

    2012-02-15

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

  15. Determination of organophosphorus insecticides (malathion and diazinon) residue in the drinking water.

    PubMed

    Shayeghi, Mansoreh; Khoobdel, Mehdi; Vatandoost, Hassan

    2007-09-01

    In this study, the amount and origin of the pollution of Karaj river and Amir-Kabir dam, which is the most important supply of Tehrans (capital of Iran) drinking water with malathion and diazinon, have been assessed by High Performance Thin Layer Chromatography (HPTLC) technique. This is a descriptive and cross-sectional study. After initial assessments, four stations were selected for water sampling. In all stations, sampling was done in one day, one week, two weeks, one month, two months and three months after insecticide spraying. Extraction and separating of organophosphorus insecticides from water samples was done by acetone and methylen chloride solvents, using decanter. Then, the residue of malathion and diazinon insecticides was determined using HPTLC technique. The residue of malathion and diazinon in water decreases with increasing the distance and time of spraying. The residues of malathion and diazinon insecticides at station 1 and 2, which were close to spraying places, 1-2 months after spraying was more than allowed limits. But at the ending stations (3 and 4), malathion and diazinon were detectable just in the 1 day and 1 month after spraying, respectively. It is unlikely that Tehran's drinking water be polluted with these two insecticides and the most adverse effect can be seen in the area of spraying. Therefore not only the environment, but also the people in area of Karaj river are at risk of chronic toxicity with malathion and diazinon through consuming polluted water and agriculture products.

  16. 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.

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

    PubMed

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

    2008-11-01

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

  18. 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....

  19. 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

  20. 76 FR 20667 - Notice of Withdrawal of Pesticide Petitions for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-13

    ... AGENCY Notice of Withdrawal of Pesticide Petitions for Residues of Pesticide Chemicals in or on Various... withdrawal of pesticide petitions (0G7716, 8F7489, 9E7635, and 9F7587) proposing the establishment or modification of regulations for residues of pesticide chemicals in or on various commodities. The...

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

    PubMed

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

    1992-07-01

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

  2. 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.

  3. Residues of organochlorine pesticides in surface soil and raw ...

    EPA Pesticide Factsheets

    The central Asian Republic of Tajikistan has been an area of extensive historical agricultural pesticide use as well as large scale burials of obsolete banned chlorinated insecticides. The current investigation was a four year study of legacy organochlorine pesticides in surface soil and raw foods in four rural areas of Tajikistan. The four study areas included the pesticide burial sites of Konibodom and Vakhsh, and family farms of Garm and Chimbuloq villages. These areas were selected to represent a diversity of pesticide disposal histories and to allow assessment of local pesticide contamination in Tajikistan. Each site was visited multiple times and over 500 samples of surface soil and raw foods were collected and analyzed for twenty legacy organochlorine pesticides. Various local food products were sampled to represent the range of raw foods potentially containing residues of banned pesticides, including dairy products, meat, edible plant and cotton seed products. The pesticide analytes included DDTs (DDT, DDD, DDE), lindane isomers (α, β, γ, δ BHC), endosulfan isomers (endosulfan I, II, sulfate), other cyclodienes (aldrin, α and γ chlordanes, dieldrin, endrin, endrin aldehyde and ketone, heptachlor, heptachlor epoxide), and methoxychlor. Pesticide analytes were selected based on availability of commercial standards and known or suspected historical pesticide use and burial. Pesticide contamination was highest in soil at each of the four sites, and ge

  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. A new method for analysis of the toxicity of organophosphorus pesticide, dimethoate on rotifer based on response surface methodology.

    PubMed

    Guo, Ruixin; Ren, Xinkun; Ren, Hongqiang

    2012-10-30

    This study analyzed the toxicity of organophosphorus pesticide, dimethoate on freshwater rotifer Brachionus calyciflorus, using swimming angular and linear speed alteration as the sub-lethal endpoints. Response surface methodology (RSM) was applied in experimental design and data analysis to consider two related factors: toxic concentration, exposure time and their interaction. In general, inhibition effect of the pesticide on rotifer swimming was observed clearly at any given toxicant concentration. The highest inhibition rates in angular and linear speed were obtained in the shortest exposure time (11.36 min) and the highest dimethoate concentration (1.85 mg L(-1)). The RSM used for the analysis of treatment combinations showed that a cubic polynomial regression model was in good agreement with experimental results, with R(2)=0.992 and 0.9997, for swimming angular speed inhibition rate and linear speed inhibition rate (p<0.01, F-test, respectively). 3D reference surface plots and contour plots showed that the toxic effect was influenced not only by dimethoate concentration, but also by the exposure time. A time-step effect was observed clearly. Thus, the pesticide dimethoate had toxic stress on the swimming behavior of rotifers.

  6. Simultaneous degradation of organophosphate and organochlorine pesticides by Sphingobium japonicum UT26 with surface-displayed organophosphorus hydrolase.

    PubMed

    Cao, Xiangyu; Yang, Chao; Liu, Ruihua; Li, Qiang; Zhang, Wei; Liu, Jianli; Song, Cunjiang; Qiao, Chuanling; Mulchandani, Ashok

    2013-04-01

    A genetically engineered microorganism (GEM) capable of simultaneously degrading organophosphate and organochlorine pesticides was constructed for the first time by display of organophosphorus hydrolase (OPH) on the cell surface of a hexachlorocyclohexane (HCH)-degrading Sphingobium japonicum UT26. The GEM could potentially be used for removing the two classes of pesticides that may be present in mixtures at contaminated sites. A surface anchor system derived from the truncated ice nucleation protein (INPNC) from Pseudomonas syringae was used to target OPH onto the cell surface of UT26, reducing the potential substrate uptake limitation. The surface localization of INPNC-OPH fusion was verified by cell fractionation, western blot, proteinase accessibility, and immunofluorescence microscopy. Furthermore, the functionality of the surface-exposed OPH was demonstrated by OPH activity assays. Surface display of INPNC-OPH fusion (82 kDa) neither inhibited cell growth nor affected cell viability. The engineered UT26 could degrade parathion as well as γ-HCH rapidly in minimal salt medium. The removal of parathion and γ-HCH by engineered UT26 in sterile and non-sterile soil was also studied. In both soil samples, a mixture of parathion (100 mg kg(-1)) and γ-HCH (10 mg kg(-1)) could be degraded completely within 15 days. Soil treatment results indicated that the engineered UT26 is a promising multifunctional bacterium that could be used for the bioremediation of multiple pesticide-contaminated environments.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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. 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

  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. Setting Tolerances for Pesticide Residues in Foods

    EPA Pesticide Factsheets

    Pesticides are widely used in producing food and may remain in small amounts in or on fruits, vegetables, grains, and other foods. EPA ensures the safety of the food supply regulating the amount of pesticide that may remain on food. Learn how we do this.

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

    PubMed

    Viñuela, Ana; Snoek, L Basten; Riksen, Joost A G; Kammenga, Jan E

    2010-08-16

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

  12. Exposure to the mixture of organophosphorus pesticides is embryotoxic and teratogenic on gestational rats during the sensitive period.

    PubMed

    Yu, Yan; Yang, Yuxuan; Zhao, Xiaodan; Liu, Xiaofei; Xue, Jianjun; Zhang, Jinghua; Yang, Aimin

    2017-01-01

    Mixture of organophosphorus pesticides (MOPs) has been used worldwide to increase food production. The MOPs are harmful, and the exposure to them is both agricultural and nonagricultural through contaminated food. The neurotoxicity of MOPs has received more consideration recently due to the increased cases of malformed fetuses suspected to be caused by the MOPs exposure during gestation; however, relevant studies in animal model are rare. In this study, we performed a comprehensive analysis and demonstrated potential perinatal embryotoxicity and teratogenicity of MOPs exposure. As results, we found that MOPs decreased in utero fetal growth and alter the ratio of organs to whole body weight of the pregnant rats. MOPs also had been shown to disturb the balance of sex hormones and affect the reproduction of rats. Furthermore, we found various significantly elevated deformities in MOPs exposed embryos, confirming the embryotoxic and teratogenic effects of maternal exposure to MOPs. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 139-146, 2017.

  13. 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.

  14. 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.

  15. 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)...

  16. 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...

  17. 40 CFR 158.2082 - Experimental use permit biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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)...

  18. 40 CFR 158.2040 - Biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false 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...

  19. 40 CFR 158.2040 - Biochemical 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 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...

  20. 40 CFR 158.2082 - Experimental use permit biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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)...

  1. 40 CFR 158.2082 - Experimental use permit biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 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)...

  2. 40 CFR 158.2040 - Biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false 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...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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 158.2040 - Biochemical pesticides residue data requirements table.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false 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...

  5. Selective solid-phase extraction using molecularly imprinted polymer for the analysis of polar organophosphorus pesticides in water and soil samples.

    PubMed

    Zhu, Xiaolan; Yang, Jun; Su, Qingde; Cai, Jibao; Gao, Yun

    2005-10-28

    An analytical methodology for the analysis of four polar organophophorus pesticides (monocrotophos, mevinphos, phosphamidon, omethoate) in water and soil samples incorporating a molecularly imprinted solid-phase extraction (MISPE) process using a monocrotophos-imprinted polymer was developed. Binding study demonstrated that the polymer showed excellent affinity and high selectivity to monocrotophos. The MISPE procedure including the clean-up step to remove any interferences was optimized. The accuracy and selectivity of the MISPE process developed were verified using a non-imprinted (blank) polymer and a classical ENVI-18 cartridge as the SPE matrix during control experiments. The use of MISPE improved the accuracy and precision of the GC method and lowered the limit of detection. The recoveries of four polar organophosphorus pesticides (OPPs) extracted from 1 L of river water at a 100 ng/L spike level were in the range of 77.5-99.1%. The recoveries of organophosphorus pesticides extracted from a 5-g soil sample at the 100 microg/kg level were in the range of 79.3-93.5%. The limit of detection varied from 10 to 32 ng/L in water and from 12 to 34 microg/kg in soil samples. The molecularly imprinted polymer (MIP) enabled the selective extraction of four organophosphorus pesticides successfully from water and soil samples, demonstrating the potential of molecularly imprinted solid-phase extraction for rapid, selective, and cost-effective sample pretreatment.

  6. 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

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

    PubMed

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

    2005-10-01

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

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

    PubMed

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

    2015-06-01

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

  9. An estimation of the exposure to organophosphorus pesticides through the simultaneous determination of their main metabolites in urine by liquid chromatography-tandem mass spectrometry.

    PubMed

    Hernández, F; Sancho, J V; Pozo, O J

    2004-09-05

    A rapid method has been developed for the determination of 4-nitrophenol (PNP) (parathion and methyl-parathion metabolite) and 3-methyl-4-nitrophenol (3-Me-PNP) (fenitrothion metabolite) in human urine by coupled-column liquid chromatography combined with tandem mass spectrometry (LC-LC-MS/MS). The LC-LC-MS/MS approach allows the determination at sub-ppb level of free metabolites by injecting the urine directly into the system and the total metabolites after a simple enzymatic hydrolysis. The method has been validated, obtaining limits of detection of 0.1 and 0.2 microg/L for 4-nitrophenol and 3-methyl-4-nitrophenol, respectively. Additionally, a multi-residue LC-MS/MS method is proposed in order to evaluate the levels of other parathion and methyl parathion metabolites. This approach allows the simultaneous determination of dimethyl phosphate (DMP), dimethyl thiophosphate (DMTP), 4-nitrophenolsulphate and 4-nitrophenolglucuronide without tedious sample treatments. The applicability of both methods is demonstrated by applying them to various urine samples from an unexposed population and a grower who applied methyl parathion. The combination of both methods allows a general overview on the presence of different metabolites (free and conjugated) and the concentration ratios between them, giving useful information on organophosphorus pesticides metabolism and excretion.

  10. Organochlorine Pesticide Residues in Plankton, Rangsit Agricultural Area, Central Thailand

    PubMed Central

    Siriwong, W.; Thirakhupt, K.; Sitticharoenchai, D.; Borjan, M.; Robson, M.

    2014-01-01

    Few studies have investigated organochlorine pesticide residue content in freshwater plankton communities in Thailand. As a result, this study looks to examine the concentration of organochlorine pesticide residues in plankton collected from Khlong 7 (canal) at Rangsit agricultural area, central Thailand from June 2006 to February 2007. The results from this study show that plankton communities were composed of microphytoplankton, microzooplankton, and mesozooplankton. The average method recoveries varied from 84% to 103% with a relative standard deviation between 0.20% and 3.72%. The concentrations of organochlorine pesticide residues during a one-year-period were in the range of 0.10–3.65 ng/g wet wt and contained DDT and derivatives > Σ endosulfan > Σ HCH > Σ heptachlor > aldrin and dieldrin > endrin and endrin aldehyde > methoxychlor, respectively. Moreover, the residues of Σ HCH, DDT and derivatives, and methoxychlor were higher during wet season than dry season (t-test, p ≤ 0.05). PMID:18777151

  11. Organochlorine pesticide residues in plankton, Rangsit agricultural area, central Thailand.

    PubMed

    Siriwong, W; Thirakhupt, K; Sitticharoenchai, D; Borjan, M; Robson, M

    2008-12-01

    Few studies have investigated organochlorine pesticide residue content in freshwater plankton communities in Thailand. As a result, this study looks to examine the concentration of organochlorine pesticide residues in plankton collected from Khlong 7 (canal) at Rangsit agricultural area, central Thailand from June 2006 to February 2007. The results from this study show that plankton communities were composed of microphytoplankton, microzooplankton, and mesozooplankton. The average method recoveries varied from 84% to 103% with a relative standard deviation between 0.20% and 3.72%. The concentrations of organochlorine pesticide residues during a one-year-period were in the range of 0.10-3.65 ng/g wet wt and contained DDT and derivatives > Sigma endosulfan > Sigma HCH > Sigma heptachlor > aldrin and dieldrin > endrin and endrin aldehyde > methoxychlor, respectively. Moreover, the residues of Sigma HCH, DDT and derivatives, and methoxychlor were higher during wet season than dry season (t-test, p

  12. Pesticide residues in essential oils: evaluation of a database.

    PubMed

    Klier, B; Knödler, M; Peschke, J; Riegert, U; Steinhoff, B

    2015-01-01

    In the context of a revision of the European Pharmacopoeia (Ph. Eur.) general monograph Essential oils (2098), the need to include a test for pesticides is being discussed. According to published literature, some oils, mainly those produced by cold pressing (e.g. citrus oils), can contain relevant amounts of pesticide residues, whereas distilled oils showed positive findings in only a few cases. Recent evaluation of a database containing 127 517 sets of data compiled over 8 years, showed positive results in 1 150 cases (0.90 per cent), and the limits of Ph. Eur. general chapter 2.8.13 Pesticide residues or Regulation (EC) 396/2005, both applicable to herbal drugs, were exceeded in 392 cases (0.31 per cent, equivalent to 34.1 per cent of the positive results), particularly in cases of oils produced by cold pressing. From these results, it can be concluded that a general test on pesticides in the Ph. Eur. general monograph on essential oils is not required for most oils used in medicinal products. Therefore, it is proposed to limit the testing of essential oils for pesticide residues to those cases where potential residues are more of a concern, either due to the type of production process or to those processes where pesticides are actively used during cultivation of the plant (e.g. as documented according to Good Agricultural and Collection Practice (GACP)). Furthermore, in order to assess any potential risk, an approach using the Acceptable Daily Intake (ADI) can be made.

  13. Characterization of P-S bond hydrolysis in organophosphorothioate pesticides by organophosphorus hydrolase.

    PubMed

    Lai, K; Stolowich, N J; Wild, J R

    1995-04-01

    The extensive use of organophosphorothioate insecticides in agriculture has resulted in the risk of environmental contamination with a variety of broadly based neurotoxins that inhibit the acetylcholinesterases of many different animal species. Organophosphorus hydrolase (OPH, EC 3.1.8.1) is a broad-spectrum phosphotriesterase that is capable of detoxifying a variety of organophosphorus neurotoxins by hydrolyzing various phosphorus-ester bonds (P-O, P-F, P-CN, and P-S) between the phosphorus center and an electrophilic leaving group. OPH is capable of hydrolyzing the P-X bond of various organophosphorus compounds at quite different catalytic rates: P-O bonds (kcat = 67-5000 s-1), P-F bonds (kcat = 0.01-500 s-1), and P-S bonds (kcat = 0.0067 to 167 s-1). P-S bond cleavage was readily demonstrated and characterized in these studies by quantifying the released free thiol groups using 5,5'-dithio-bis-2-nitrobenzoic acid or by monitoring an upfield shift of approximately 31 ppm by 31P NMR. A decrease in the toxicity of hydrolyzed products was demonstrated by directly quantifying the loss of inhibition of acetylcholinesterase activity. Phosphorothiolate esters, such as demeton-S, provided noncompetitive inhibition for paraoxon (a P-O triester) hydrolysis, suggesting that the binding of these two different classes of substrates was not identical.

  14. Efficient immobilization of acetylcholinesterase onto amino functionalized carbon nanotubes for the fabrication of high sensitive organophosphorus pesticides biosensors.

    PubMed

    Yu, Guangxia; Wu, Weixiang; Zhao, Qiang; Wei, Xiaoyun; Lu, Qing

    2015-06-15

    This work introduced an efficient immobilization of acetylcholinesterase (AChE) onto amino functionalized carbon nanotubes (CNT-NH2), in order to fabricate high sensitive and practical organophosphorus pesticide (OPs) biosensors. Compared with the pristine, -COOH and -OH decorated CNTs, there were larger amount of enzymes adsorbed on the surface of CNT-NH2 with a favorable orientation and the best amperometric response was obtained on the AChE/CNT-NH2/GC electrode. Furthermore, the biosensor modified with CNT-NH2 showed a high affinity to acetylthiocholine chloride (ATCh) and could catalyze the hydrolysis of ATCh with an apparent Michaelis-Menten constant (Km) value of 67.4 µM. Using paraoxon as a model compound, wide linear ranges from 0.2 nM to 1 nM and 1 nM to 30 nM, and a low detection limit of 0.08 nM were obtained with satisfactory reproducibility and stability. Moreover, the biosensor had also been successfully employed for the determination of low concentrations of pesticides in real vegetable samples. This method could be extended to other functionalized nano-materials for their application in constructing biosensors.

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

    PubMed

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

    2014-09-01

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

  16. Impaired antioxidant gene expression by pesticide residues and its relation with other cellular biomarkers in Nile Tilapia (Oreochromis niloticus) from Lake Burullus.

    PubMed

    El Nahas, Abeer F; Abdel-Razek, Mohamed A S; Helmy, Nashwa M; Mahmoud, Shawky; Ghazy, Haneen A

    2017-03-01

    Organochlorines and Organophosphorus are the most commonly used pesticides. These pesticides constitute a considerable contaminating threat due to their excessive agricultural usage which in turn contaminates the aquatic system through agricultural drainage. The aim of this study was to evaluate water and tissue residues of both pesticides in O. niloticus obtained from three different sections in Lake Burullus, Egypt. Assessment of relative change in mRNA levels of GST and Vtg (oxidative stress indicator) was done and its relation with other cellular biomarkers including apoptosis, which is assessed by Cellular apoptosis susceptibility transcript level (CAS), comet assay and micronucleus assays (genotoxicity indicator). Pesticide residue levels in water are fluctuating. In fish tissues, most residues were higher than those found in water and were associated with down regulation of hepatic GST gene and Vtg expression. CAS gene involved in apoptosis, its transcript is down regulated in middle and western sections of the lake with higher pesticide residues. Different degrees of DNA damages in O. niloticus' liver cells were demonstrated by comet assay. Significant increase in the micronucleated cells in the three sections of the lake was observed; the western section fish showed the highest number. Persistent exposures of fish to pesticide caused impairment of antioxidant gene expression. This negatively affects apoptosis associated with damaging DNA and chromosome fragments.

  17. Poly(phthalazine ether sulfone ketone) as novel stationary phase for stir bar sorptive extraction of organochlorine compounds and organophosphorus pesticides.

    PubMed

    Guan, Wenna; Wang, Yanjuan; Xu, Feng; Guan, Yafeng

    2008-01-04

    A novel poly(phthalazine ether sulfone ketone) (PPESK) film prepared by immersion precipitation technique was coated on stir bars for sorptive extraction. Scanning electron micrographs showed that the coating has a denser porous surface (about 1 microm in thickness) with a sponge-like sublayer, and the thickness of the coating was 250 microm. The PPESK coated stir bar has high thermostability (290 degrees C) and long lifetime (50 times). The extraction properties of this stir bar were evaluated for the extraction of both polar and semi-polar analytes, including organochlorine compounds and organophosphorus pesticides. The PPESK stir bar was proved to show higher affinity towards polar compounds than that of PDMS coated stir bar and higher sample load compared with corresponding PPESK fiber. It was applied to the determination of organochlorine compounds in seawater samples and organophosphorus pesticides in juices by gas chromatographic analysis. The effect of sample matrix was evaluated at optimized condition of extraction temperature, extraction time and salt concentration. Limits of detection were in the range of 0.05-2.53 ng L(-1) for organochlorine compounds in seawater samples using electron capture detector (ECD), with precisions of less than 11% RSD. Limits of detection for organophosphorus pesticides were in the range of 0.17-2.25 ng L(-1) and 2.47-10.3 ng L(-1) in grape and peach juice, respectively, using thermionic specified detector (TSD), with precisions of less than 12% RSD and 20% RSD, respectively.

  18. Screening and evaluation of fruit samples for four pesticide residues.

    PubMed

    Blasco, Cristina; Font, Guillermina; Mañes, Jordi; Picó, Yolanda

    2005-01-01

    The occurrence of 4 pesticide residues, imidacloprid, carbendazim, methiocarb, and hexythiazox, was assessed in several fruits (oranges, tangerines, watermelons, and date plums) from the Valencian Community (Spain). A total of 227 samples--56 oranges, 134 tangerines, 13 watermelons, and 24 date plums--were taken from an agricultural cooperative representative of the area studied during 2001. The pesticides were determined by liquid chromatography/mass spectrometry after sample extraction with ethyl acetate and anhydrous sodium sulfate. Recoveries of 4 pesticides at 2 fortification levels (0.02 and 0.2 mg/kg), the lower of which was the quantification limit, ranged from 60 to 108%. Concentrations of imidacloprid, carbendazim, methiocarb, and hexythiazox ranged from 0.02 to 0.75 mg/kg in 184 samples (54 oranges, 119 tangerines, 3 watermelons, and 8 date plums). Nineteen samples contained methiocarb or hexythiazox residues that exceeded the maximum residue limits. Calculation of the estimated daily intakes of the 4 pesticides studied and their comparison with the Acceptable Daily Intakes established by the Food and Agriculture Organization of the World Health Organization demonstrated the safety of fruit consumption and showed the importance of monitoring for pesticide residues.

  19. 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.

  20. A novel layer-by-layer assembled multi-enzyme/CNT biosensor for discriminative detection between organophosphorus and non-organophosphrus pesticides.

    PubMed

    Zhang, Yuanyuan; Arugula, Mary A; Wales, Melinda; Wild, James; Simonian, Aleksandr L

    2015-05-15

    Organophosphate compounds are heavily used in agriculture and military activities, while non-organophosphate pesticides are mostly used in agriculture and home defense. Discriminative detection of such toxic compounds is very challenging and requires sophisticated and bulky instrumentation. Meanwhile, multi-enzyme biosensors may offer an effective solution to the problem and may become a versatile analytical tool for discriminative detection of different neurotoxins. In this study, we report for the first time a novel bi-enzyme biosensing system incorporating electrostatically interacted enzyme-armored MWCNT-OPH and MWCNT-AChE along with a set of cushioning bilayers consisting of MWCNT-polyethyleneimine and MWCNT-DNA on glassy carbon electrode for discriminative detection of organophosphorus (OP) and non-organophosphorus (non-OP) pesticides. LbL interfaces were characterized by surface plasmon resonance and electrochemical impedance spectroscopy, demonstrating stepwise assembly and electron conductivity studies. The detection limit was found to be ~0.5 for OP pesticide paraoxon and 1 μM for non-OP pesticide carbaryl, in a wide linear range. The biosensor performance was also validated using apple samples. Remarkable discriminative and straightforward detection between OP and non-OP neurotoxins was successfully achieved with cyclic voltammetry (CV) and UV-vis methods on the MWCNT-(PEI/DNA)2/OPH/AChE biosensor, showing great potential in large screening of OP and non-OP pesticides in practical applications.

  1. 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.,...

  2. 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...

  3. 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.

  4. 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).

  5. 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.

  6. Determination of pesticide residues in sewage sludge: a review.

    PubMed

    Tadeo, José L; Sánchez-Brunete, Consuelo; Albero, Beatriz; García-Valcárcel, Ana I

    2010-01-01

    Pesticides are widely applied to protect plants from diseases, weeds, and insect damage, and they usually come into contact with soil where they may undergo a variety of transformations and provide a complex pattern of metabolites. Spreading sewage sludge on agricultural lands has been actively promoted by national authorities as an economic way of recycling. However, as a byproduct of wastewater treatment, sewage sludge may contain pesticides and other toxic substances that could be incorporated into agricultural products or be distributed in the environment. This article reviews the determination of pesticides in sewage sludge samples. Sample preparation including pretreatment, extraction, and cleanup, as well as the subsequent instrumental determination of pesticide residues, are discussed. Extraction techniques such as Soxhlet extraction, ultrasound-assisted extraction, pressurized liquid extraction, supercritical fluid extraction, and matrix solid-phase dispersion and their most recent applications to the determination of pesticides in sewage sludge samples are reviewed. Determination of pesticides, generally carried out by GC and HPLC coupled with different detectors, especially MS for the identification and quantification of residues, is summarized and discussed.

  7. Reduction of pesticide residues in tomatoes and other produce.

    PubMed

    Al-Taher, Fadwa; Chen, Yang; Wylie, Philip; Cappozzo, Jack

    2013-03-01

    There is interest in reducing pesticide residues in fruits and vegetables in order to minimize human exposure. The objectives of this study were to (i) determine the effect of various washing treatments with and without sonication on pesticide removal from tomatoes and (ii) assess the effectiveness of a water wash on select samples using a produce-washing flume. In the first set of experiments, tomatoes were contaminated with acephate, malathion, carbaryl, bifenthrin, cypermethrin, permethrin, cyhalothrin, chlorothalonil, and imidacloprid and were dried overnight. Subsets of the tomatoes were then washed (10°C, 1 min) with one of the following: water, sodium hypochlorite (80 μg/ml, pH 7), peroxyacetic acid (80 μg/ml), or Tween 20 (0.1%) with and without sonication. In general, the effect of sonication depended on the washing treatment and on the pesticide. A separate experiment measured pesticide residues in contaminated samples before and after being washed in a flume (22°C, 1 min). Pesticide residues in contaminated produce were reduced from about 40 to 90% when washed for 1 min in the flume.

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

    USGS Publications Warehouse

    Eccles, Lawrence A.

    1979-01-01

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

  9. 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...

  10. EPA Method 614: The Determination of Organophosphorus Pesticides in Municipal and Industrial Wastewater

    EPA Pesticide Factsheets

    Method 614 describes procedures for preparation and analysis of samples for determination of organophosphate pesticides in industrial and municipal discharges using a GC with a phosphorus-specific flame photometric detector (FPD).

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

    PubMed

    Ambrus, Árpád

    2016-01-13

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

  12. 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...

  13. 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...

  14. 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...

  15. Sampling and sample processing in pesticide residue analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. The status of pesticide residues in the drinking water sources in Meiliangwan Bay, Taihu Lake of China.

    PubMed

    Na, Ta; Fang, Zhou; Zhanqi, Gao; Ming, Zhong; Cheng, Sun

    2006-12-01

    The study was carried out to assess the levels of pesticide residues in the water of Meiliangwan Bay, Taihu Lake of China. The most commonly employed organochlorine pesticides (OCPs), organophosphorus pesticides (OPPs) and herbicide atrazine were analyzed. The water samples were collected seasonally from Meiliangwan Bay within a period of one year. The pesticides were analyzed by gas chromatography (GC) with microECD or NPD after solid-phase extraction (SPE), which was confirmed by GC with an ion trap mass spectrometry (MS). The mean concentrations were 1.98 ng/l for lindane, 0.378 ng/l for heptachlor epoxide, 0.367 ng/l for p,p'-DDE, 0.496 ng/l for p,p'-DDD, 1.06 ng/l for p,p'-DDT and 51.6 ng/l for dichlorvos, 39.0 ng/l for demeton, 346 ng/l for dimethoate, 4.12 ng/l for methyl parathion, 11.6 ng/l for malathion, 2.17 ng/l for parathion and 217 ng/l for atrazine. Generally, low concentrations of OCP were found, whereas the concentrations of the OPPs and atrazine in the water of Taihu Lake were relatively high. Heptachlor epoxide and lindane were the two most commonly encountered OCPs while dichlorvos, demeton and dimethoate were found to have much higher concentrations and occurrences than other OPPs.

  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, 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...

  19. 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...

  20. 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...

  1. 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...

  2. Pesticide residue analysis of a dietary ingredient by gas chromatography/selected-ion monitoring mass spectrometry using neutral alumina solid-phase extraction cleanup.

    PubMed

    Jeong, Mijeong Lee; Zahn, Michael; Trinh, Thao; Brooke, Fay A; Ma, Wenwen

    2008-01-01

    A sample cleanup procedure has been developed to remove coextractives that interfere with pesticide residue analysis of a dietary ingredient (Product B), an extract consisting of Scutellaria baicalensis and Acacia catechu. Samples were extracted using 1% acetic acid in acetonitrile, followed by solid-phase extraction and analysis by capillary gas chromatography with mass spectrometry in the selective-ion monitoring mode. Neutral alumina (alumina N) was found to be the most effective sorbent to remove coextractives from Product B; other materials that were tested but failed to remove interference were graphitized carbon black/primary-secondary amine (PSA), octadecylsilane (C18), Florisil, Oasis MCX, and strong anion exchange-PSA. The method was specifically developed for Product B, which was spiked with 41 organochlorine and organophosphorus pesticides, and resulted in the recovery of 80 to 120% at U.S. Pharmacopeia limits (0.06 to 4 microg/g) for the majority of the pesticides.

  3. Application of solid-phase microextraction for the determination of organophosphorus pesticides in textiles by gas chromatography with mass spectrometry.

    PubMed

    Zhu, Fang; Ruan, Wenhong; He, Minheng; Zeng, Feng; Luan, Tiangang; Tong, Yexiang; Lu, Tongbu; Ouyang, Gangfeng

    2009-09-21

    A method based on solid-phase microextraction (SPME) and gas chromatography with mass spectrometry (GC/MS) for the determination of 18 organophosphorus pesticides (OPPs) in textiles is described. Commercially available SPME fibers, 100 microm PDMS and 85 microm PA, were compared and 85 microm PA exhibited better performance to the OPPs. Various parameters affecting SPME, including extraction and desorption time, extraction temperature, salinity and pH, were studied. The optimized conditions were: 35 min extraction at 25 degrees C, 5% NaSO4 content, pH 7.0, and 3.5 min desorption in GC injector port at 250 degrees C. The linear ranges of the SPME-GC/MS method were 0.1-500 microg L(-1) for most of the OPPs. The limits of detection (LODs) ranged from 0.01 microg L(-1) (for bromophos-ethyl) to 55 microg L(-1) (for azinphos-methyl) and the RSDs were between 0.66% and 9.22%. The optimized method was then used to analyze 18 OPPs in textile sample, and the determined recoveries were ranged from 76.7% to 126.8%. Moreover, the distribution coefficients of the OPPs between 85 microm PA fiber and simulative sweat solution (K(pa/s)) were determined. The determined K(pa/s) of the OPPs correlated well with their octanol-water partition coefficients (r=0.764 and 0.678) and water solubility (r=-0.892 and -0.863).

  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. Innovative approach for the electrochemical detection of non-electroactive organophosphorus pesticides using oxime as electroactive probe.

    PubMed

    Dong, Jing; Hou, Juying; Jiang, Jianxia; Ai, Shiyun

    2015-07-23

    An innovative approach for sensitive and simple electrochemical detection of non-electroactive organophosphorus pesticides (OPs) was described in this report. The novel strategy emphasized the fabrication of an oxime-based sensor via attaching pralidoxime (PAM) on graphene quantum dots (GQDs) modified glassy carbon electrode. The introduction of GQDs significantly increased the effective electrode area, and then enlarged the immobilization quantity of PAM. Thus, the oxidation current of PAM was obviously increased. Relying on the nucleophilic substitution reaction between oxime and OPs, fenthion was detected using PAM as the electroactive probe. Under optimum conditions, the difference of oxidation current of PAM was proportional to fenthion concentration over the range from 1.0×10(-11)M to 5.0×10(-7)M with a detection limit of 6.8×10(-12)M (S/N=3). Moreover, the favorable detection performance in water and soil samples heralded the promising applications in on-site OPs detection.

  6. 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.

  7. 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).

  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. An improved dispersive solid-phase extraction clean-up method for the gas chromatography-negative chemical ionisation tandem mass spectrometric determination of multiclass pesticide residues in edible oils.

    PubMed

    Deme, Pragney; Azmeera, Tirupathi; Prabhavathi Devi, B L A; Jonnalagadda, Padmaja R; Prasad, R B N; Vijaya Sarathi, U V R

    2014-01-01

    An improved sample preparation using dispersive solid-phase extraction clean-up was proposed for the trace level determination of 35 multiclass pesticide residues (organochlorine, organophosphorus and synthetic pyrethroids) in edible oils. Quantification of the analytes was carried out by gas chromatography-mass spectrometry in negative chemical ionisation mode (GC-NCI-MS/MS). The limit of detection and limit of quantification of residues were in the range of 0.01-1ng/g and 0.05-2ng/g, respectively. The analytes showed recoveries between 62% and 110%, and the matrix effect was observed to be less than 25% for most of the pesticides. Crude edible oil samples showed endosulfan isomers, p,p'-DDD, α-cypermethrin, chlorpyrifos, and diazinon residues in the range of 0.56-2.14ng/g. However, no pesticide residues in the detection range of the method were observed in refined oils.

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

    EPA Science Inventory

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

  11. 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

  12. 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.

  13. 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

    1997-12-03

    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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  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.

  20. Parameters affecting the decay of some organophosphorus pesticides: a study by high-performance liquid chromatography.

    PubMed

    Kaur, I; Mathur, R P; Tandon, S N

    1997-01-01

    An HPLC procedure has been developed to follow the decay of malathion and methylparathion under control conditions using an mu-Bondapak C18 column with a mixture of acetonitrile and water to mobile phase and an ultraviolet detector for detection. Studies have been conducted to monitor their degradation in water and soil at different temperatures, pH and organic content. The results show that the persistence of the pesticides decreases with increase in temperature, pH and organic content.

  1. 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

  2. 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.

  3. Pesticide Residues and Bees – A Risk Assessment

    PubMed Central

    Sanchez-Bayo, Francisco; Goka, Koichi

    2014-01-01

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

  4. 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.

  5. 77 FR 3229 - Codex Alimentarius Commission: Codex Committee on Pesticide Residues (CCPR)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-23

    ... No. FSIS-2011-0035] Codex Alimentarius Commission: Codex Committee on Pesticide Residues (CCPR....) positions that will be discussed at the 44th Session of the Codex Committee on Pesticide Residues (CCPR) of... SESSION OF THE CCPR CONTACT: Lois Rossi, Director of Registration Division, Office of Pesticide...

  6. 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.

  7. 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.

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

    PubMed

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

    2013-12-15

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

  9. An integrated probabilistic framework for cumulative risk assessment of common mechanism chemicals in food: an example with organophosphorus pesticides.

    PubMed

    Bosgra, Sieto; van der Voet, Hilko; Boon, Polly E; Slob, Wout

    2009-07-01

    This paper presents a framework for integrated probabilistic risk assessment of chemicals in the diet which accounts for the possibility of cumulative exposure to chemicals with a common mechanism of action. Variability between individuals in the population with respect to food consumption, concentrations of chemicals in the consumed foods, food processing habits and sensitivity towards the chemicals is addressed by Monte Carlo simulations. A large number of individuals are simulated, for which the individual exposure (iEXP), the individual critical effect dose (iCED) and the ratio between these values (the individual margin of exposure, iMoE) are calculated by drawing random values for all variable parameters from databases or specified distributions. This results in a population distribution of the iMoE, and the fraction of this distribution below 1 indicates the fraction of the population that may be at risk. Uncertainty in the assessment is treated as a separate dimension by repeating the Monte Carlo simulations many times, each time drawing random values for all uncertain parameters. In this framework, the cumulative exposure to common mechanism chemicals is addressed by incorporation of the relative potency factor (RPF) approach. The framework is demonstrated by the cumulative risk assessment of organophosphorus pesticides (OPs). By going through this example, the various choices and assumptions underlying the cumulative risk assessment are made explicit. The problems faced and the solutions chosen may be more generic than the present example with OPs. This demonstration may help to familiarize risk assessors and risk managers with the somewhat more complex output of probabilistic risk assessment.

  10. 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.

  11. 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.

  12. Contamination of liquid milk and butter with pesticide residues in the Ludhiana district of Punjab state, India.

    PubMed

    Battu, R S; Singh, Balwinder; Kang, B K

    2004-11-01

    An analysis of 92 samples of liquid milk from Ludhiana, India, during 1999-2001 revealed the presence of DDT in 6 (7.4%) samples and of these 2 samples were found to exceed the maximum residue limit (MRL) of DDT fixed at 0.05 mg kg(-1) (on a whole milk basis). HCH residues were detected in 49 (53.3%) samples and constituted only gamma-HCH (lindane). The MRL of lindane is fixed at 0.01 mg kg(-1) (whole milk basis), and all 49 liquid milk samples exceeded this value. These results are indicative of contamination of bovine milk with pesticide residues as a result of the ban on the use of DDT and HCH in agriculture and public health programs. Similarly, analysis of 40 samples of butter showed the presence of DDT and HCH in 28 and 8 samples, respectively. However, none of the samples exceeded the MRL value of either DDT or any isomer of HCH. DDT residues comprised mainly p,p-DDE and p,p-TDE, whereas HCH residues were present as lindane in 6 samples, and 2 samples revealed the presence of beta-HCH. The estimated daily intake of lindane through the consumption of contaminated liquid milk exceeded its acceptable daily intake value for children. Interestingly, none of the liquid milk or butter samples revealed the presence of any commonly used organophosphorus or synthetic pyrethroid insecticides at their detection limit of 0.01 mg kg(-1).

  13. Simultaneous determination of urinary dialkylphosphate metabolites of organophosphorus pesticides using gas chromatography-mass spectrometry.

    PubMed

    Ueyama, Jun; Saito, Isao; Kamijima, Michihiro; Nakajima, Tamie; Gotoh, Masahiro; Suzuki, Takayoshi; Shibata, Eiji; Kondo, Takaaki; Takagi, Kenji; Miyamoto, Ken-ichi; Takamatsu, Junki; Hasegawa, Takaaki; Takagi, Kenzo

    2006-02-17

    In this study, we developed a safe and sensitive method for the simultaneous determination of urinary dialkylphosphates (DAPs), metabolites of organophosphorus insecticides (OPs), including dimethylphosphate (DMP), diethylphosphate (DEP), dimethylthiophosphate (DMTP), and diethylthiophosphate (DETP), using a pentafluorobenzylbromide (PFBBr) derivatization and gas chromatography-mass spectrometry (GC-MS). Several parameters were investigated: pH on evaporation, reaction temperature and time for the derivatization, the use of an antioxidant for preventing oxidation, and a clean-up step. The pH was set at 6, adjusted with K2CO3, and the reaction temperature and time of derivatization were 80 degrees C and 30 min, respectively. Sodium disulfite was chosen as an antioxidant. The clean-up step was performed with a Florisil/PSE mini-column to remove the unreacted PFBBr and sample matrix. This established procedure markedly shortened the sample preparation time to only about 3 h, and completely inhibited the unwanted oxidization of dialkylthiophosphates. The limits of determination (LOD) were approximately 0.3 microg/L for DMP, and 0.1 microg/L for DEP, DMTP, and DETP in 5 mL of human urine. Within-series and between-day imprecision for the present method using pooled urine spiked with DAPs was less than 20.6% in the calibration range of 1-300 microg/L, and the mean recovery was 56.7-60.5% for DMP, 78.5-82.7% for DEP, 88.3-103.9% for DMTP, and 84.2-92.4% for DETP. This method detected geometric mean values of the urinary DAPs in Japanese with and without occupational exposure to OPs, 16.6 or 27.4 for DMP, 1.0 or 0.7 for DEP, 1.3 or 2.3 for DMTP, and 1.0 or 1.1 microg/L for DETP, respectively. The present method, which does not require special equipment except for GC-MS, is quick, safe, and sensitive enough to be adopted in routine biological monitoring of non-occupational as well as occupational exposure to OPs.

  14. 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.

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

    PubMed

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

    2008-12-01

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

  17. New magnetic graphene-based inorganic-organic sol-gel hybrid nanocomposite for simultaneous analysis of polar and non-polar organophosphorus pesticides from water samples using solid-phase extraction.

    PubMed

    Rashidi Nodeh, Hamid; Wan Ibrahim, Wan Aini; Kamboh, Muhammad Afzal; Sanagi, Mohd Marsin

    2017-01-01

    A new graphene-based tetraethoxysilane-methyltrimethoxysilane sol-gel hybrid magnetic nanocomposite (Fe3O4@G-TEOS-MTMOS) was synthesised, characterized and successfully applied in magnetic solid-phase extraction (MSPE) for simultaneous analysis of polar and non-polar organophosphorus pesticides from several water samples. The Fe3O4@G-TEOS-MTMOS nanocomposite was characterized using Fourier transform-infrared spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy and X-ray diffraction. Separation, determination and quantification were achieved using gas chromatography coupled with micro electron capture detector. Adsorption capacity of the sorbent was calculated using Langmuir equation. MSPE was linear in the range 100-1000 pg mL(-1) for phosphamidon and dimethoate, and 10-100 pg mL(-1) for chlorpyrifos and diazinon, with limit of detection (S/N = 3) of 19.8, 23.7, 1.4 and 2.9 pg mL(-1) for phosphamidon, dimethoate, diazinon and chlorpyrifos, respectively. The LODs obtained is well below the maximum residual level (100 pg mL(-1)) as set by European Union for pesticides in drinking water. Acceptable precision (%RSD) was achieved for intra-day (1.3-8.7%, n = 3) and inter-day (7.6-17.8%, n = 15) analyses. Fe3O4@G-TEOS-MTMOS showed high adsorption capacity (54.4-76.3 mg g(-1)) for the selected OPPs. No pesticide residues were detected in the water samples analysed. Excellent extraction recoveries (83-105%) were obtained for the spiked OPPs from tap, river, lake and sea water samples. The newly synthesised Fe3O4@G-TEOS-MTMOS showed high potential as adsorbent for OPPs analysis.

  18. Determination of trace organophosphorus pesticides in water samples with TiO2 nanotubes cartridge prior to GC-flame photometric detection.

    PubMed

    Huang, Yunrui; Zhou, Qingxiang; Xiao, Junping; Xie, Guohong

    2010-07-01

    This article described a new method for the sensitive determination of organophosphorus pesticides in water samples using SPE in combination with GC-flame photometric detection. In the procedure of method development, TiO(2) nanotubes were used as SPE adsorbents for the enrichment of organophosphorus pesticides from water samples. Several factors, such as eluent and its volume, sample pH, sample volume, sample flow rate, and concentration of humic acid, were optimized. Under the optimal conditions, the proposed method had good linear ranges as 0.1-40 microg/L for each of them, LOD of 0.11, 0.014, and 0.0025 microg/L, and LOQs of 0.37, 0.047, and 0.0083 microg/L for chlorpyrifos, phorate, and methyl parathion, respectively. The proposed method was validated with real environmental water samples and the spiked recoveries were over the range of 86.5-115.1%. All these results indicated that TiO(2) nanotubes, as a new SPE adsorbent, would be used widespread for the preconcentration and determination of environmental pollutants in the future.

  19. Temperature-controlled ultrasound- and vortex-assisted liquid-liquid microextraction combined with GC for the determination of the concentrations of organophosphorus pesticides in beverage samples.

    PubMed

    Wu, Tong; Zhao, Wenting; Yang, Zhonghua; Gao, Haixiang; Zhou, Zhiqiang

    2013-12-01

    The aim of this work was to develop temperature-controlled ultrasound- and vortex-assisted liquid-liquid microextraction as a fast and efficient approach for the extraction of nine organophosphorus pesticides in beverage samples followed by GC with flame photometric detection analysis. The combination of ultrasonication and vortexing were used to assist the microextraction, and the use of a dispersion solvent was avoided. Several variables that could potentially affect the extraction efficiency, namely, the type and volume of extraction solvent, sequence, and time of ultrasonication and vortexing, ultrasonication bath temperature and ionic strength were optimized. Under optimum conditions, the calibration graphs were linear over the range of 0.5-200 μg/L. The LOD (S/N = 3) was between 0.01 and 0.05. The optimized method exhibited a good precision level with RSD values between 4.5 and 9.8%. The enrichment factors for the nine organophosphorus pesticides were between 224 and 339. Four beverage samples were successfully analyzed using the proposed method.

  20. Isolation of the opdE gene that encodes for a new hydrolase of Enterobacter sp. capable of degrading organophosphorus pesticides.

    PubMed

    Chino-Flores, Concepción; Dantán-González, Edgar; Vázquez-Ramos, Alejandra; Tinoco-Valencia, Raunel; Díaz-Méndez, Rafael; Sánchez-Salinas, Enrique; Castrejón-Godínez, Maria Luisa; Ramos-Quintana, Fernando; Ortiz-Hernández, Maria Laura

    2012-06-01

    Microbial enzymes that can hydrolyze organophosphorus compounds have been isolated, identified and characterized from different microbial species in order to use them in biodegradation of organophosphorus compounds. We isolated a bacterial strain Cons002 from an agricultural soil bacterial consortium, which can hydrolyze methyl-parathion (MP) and other organophosphate pesticides. HPLC analysis showed that strain Cons002 is capable of degrading pesticides MP, parathion and phorate. Pulsed-field gel electrophoresis and 16S rRNA amplification were performed for strain characterization and identification, respectively, showing that the strain Cons002 is related to the genus Enterobacter sp. which has a single chromosome of 4.6 Mb and has no plasmids. Genomic library was constructed from DNA of Enterobacter sp. Cons002. A gene called opdE (Organophosphate Degradation from Enterobacter) consists of 753 bp and encodes a protein of 25 kDa, which was isolated using activity methods. This gene opdE had no similarity to any genes reported to degrade organophosphates. When kanamycin-resistance cassette was placed in the gene opdE, hydrolase activity was suppressed and Enterobacter sp. Cons002 had no growth with MP as a nutrients source.

  1. 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.

  2. 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...

  3. Determination of Pesticides Residues in Cucumbers Grown in Greenhouse and the Effect of Some Procedures on Their Residues

    PubMed Central

    LEILI, Mostafa; PIRMOGHANI, Amin; SAMADI, Mohammad Taghi; SHOKOOHI, Reza; ROSHANAEI, Ghodratollah; POORMOHAMMADI, Ali

    2016-01-01

    Background: The objective of this study was to determine the residual concentrations of ethion and imidacloprid in cucumbers grown in greenhouse. The effect of some simple processing procedures on both ethion and imidacloprid residues were also studied. Methods: Ten active greenhouses that produce cucumber were randomly selected. Ethion and imidacloprid as the most widely used pesticides were measured in cucumber samples of studied greenhouses. Moreover, the effect of storing, washing, and peeling as simple processing procedures on both ethion and imidacloprid residues were investigated. Results: One hour after pesticide application; the maximum residue levels (MRLs) of ethion and imidacloprid were higher than that of Codex standard level. One day after pesticide application, the levels of pesticides were decreased about 35 and 31% for ethion and imidacloprid, respectively, which still were higher than the MRL. Washing procedure led to about 51 and 42.5% loss in ethion and imidacloprid residues, respectively. Peeling procedure also led to highest loss of 93.4 and 63.7% in ethion and imidacloprid residues, respectively. The recovery for both target analytes was in the range between 88 and 102%. Conclusion: The residue values in collected samples one hour after pesticides application were higher than standard value. The storing, washing, and peeling procedures lead to the decrease of pesticide residues in greenhouse cucumbers. Among them, the peeling procedure has the greatest impact on residual reduction. Therefore, these procedures can be used as simple and effective processing techniques for reducing and removing pesticides from greenhouse products before their consumption. PMID:28032066

  4. Toxicological assessment of isomeric pesticides: a strategy for testing of chiral organophosphorus (OP) compounds for delayed polyneuropathy in a regulatory setting.

    PubMed

    Battershill, Jon M; Edwards, Philippa M; Johnson, Martin K

    2004-08-01

    Many compounds, including some pesticides, contain structural centres of asymmetry, which convey the property of a type of stereoisomerism known as chirality. Such compounds can exist in two or more forms, depending on the number of chiral atoms and are termed stereoisomers or enantiomers. Stereoisomers of a particular compound can have different biological properties; one such of particular importance for toxicological evaluation, is the potential for differences in metabolic disposal of and binding of stereoisomers to molecular targets in the cell. The combination of differential metabolism of chiral organophosphorus (OP) pesticides and opposing stereoselectivity of inhibition of neuropathy target esterase (NTE) and acetylcholinesterase (AChE) can affect the value of the hen test, performed to OECD guidelines, in predicting the potential to cause organophosphate-induced delayed polyneuropathy (OPIDP) in humans. This is a mixed central and sensory and motor neuropathy. The experimental data on structural analogues of the pesticide methamidophos and the evidence for stereoselective OPIDP are reviewed and a model is given demonstrating how the properties of a chiral OP can result in the neuropathic potential not being detected by the standard hen test. A strategy for the assessment of a racemic mixture comprised of two OP enantiomers for the potential to induce OPIDP is outlined. The strategy uses information from structure activity relationships (SAR), in vitro tests and in vivo tests to allow risk assessment decisions to be made. It is suggested that the potential for stereoselective toxicity of pesticides should be routinely considered in regulatory assessments.

  5. LC-MS/MS determination of pesticide residues in fruits and vegetables.

    PubMed

    Stachniuk, Anna; Szmagara, Agnieszka; Czeczko, Renata; Fornal, Emilia

    2017-03-29

    The aim of the research is to evaluate pesticide residue contamination of fresh and frozen fruits and vegetables, agricultural raw material, purchased from Polish farmers for production of frozen fruits and vegetables, and the estimation of the multiresidue method effectiveness expressed as the proportion of pesticides detected in food samples to the total number of pesticides analyzed by multiresidue methods. A total of 144 samples (of black currants, red currants, raspberries, cherries, strawberries, blackberries, cauliflowers and broccoli) were analyzed using LC-MS/MS method for the determination of 60 pesticides. QuEChERS extraction, matrix-matched calibration and dynamic multiple reaction monitoring method were used. Residues of 15 compounds, mainly fungicides and insecticides, were detected in 46 samples. The percentage of samples with residues above the maximum residue levels (MRL) was 15%, whereas samples with residues below MRL were 17%. A total of 13 samples contained more than one pesticide residue. Pesticide residues were detected most often in samples of black currants (50%), broccoli (36.4%), raspberries (29%) and red currants (21.8%). The most frequently detected pesticides were carbendazim and acetamiprid. The proportion of pesticides detected during our study to the total number of analyzed pesticides amounted to 25%. It was compared to literature findings. For three fourth of multiresidue methods, the proportion was below 50% for methods developed for the analysis of less than 100 pesticides, and below 30% for methods developed for the analysis of more than 100 pesticides. It appears that a lot of efforts and means is lost on pesticides never or rarely detected in examined samples. The workload and cost effectiveness of the development and application of multiresidue methods along with the range of pesticides covered by the method should be carefully and thoroughly considered anytime when a new method or workflow is developed. Including non

  6. 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

  7. 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

    2016-03-07

    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.

  8. 78 FR 76589 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ... 25, 2012, and January 16, 2013, concerning a new active ingredient (AI) and several pesticide petitions (PP) filed for residues of pesticide chemicals. The name of an AI was changed during the registration assessment process. This document corrects the name of an AI and also corrects a PP...

  9. A Multi Residue GC-MS Method for Determination of 12 Pesticides in Cucumber

    PubMed Central

    Nasiri, Azadeh; Amirahmadi, Maryam; Mousavi, Zahra; Shoeibi, Shahram; Khajeamiri, Alireza; Kobarfard, Farzad

    2016-01-01

    Cucumber is one of the main vegetables in Iranian food basket. A wide range of pesticides are used for crops protection during the cultivation of vegetables such as cucumber due to heavy pest infestation. Analysis of pesticide residues in food and other environmental commodities have become essential requirement for consumers, producers, and food quality control authorities. This study was aimed at determination of pesticides residues in cucumber as a main vegetable in Iranian food basket. A reliable, rapid and accurate method based on spiked calibration curves and modified QuEChERS sample preparation was developed for determination of 12 pesticide residues in cucumber by gas chromatography-mass spectrometry (GC/MS). The use of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects. The recovery of pesticides at 5 concentration levels (n = 3) was in the range of 80.6-112.3. The method was proved to be repeatable with RSD lower than 20%. The limits of detection and quantification for all pesticides were <10 ng/g and <25 ng/g, respectively. The developed method was used for simultaneous determination of the selected pesticides in 60 greenhouse and garden cucumber samples. Among the 60 analyzed samples, 41.7% of them were contaminated with pesticide residues which 31.7% of samples had pesticide residues lower than maximum residue limit and 10% of samples had residue higher than maximum residue limit. PMID:28243277

  10. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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

  11. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

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

  12. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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

  13. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

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

  14. 7 CFR 29.429 - Disposition of imported tobacco exceeding pesticide residue standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

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

  15. Pesticide residues in Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) from Southern Lake Victoria, Tanzania.

    PubMed

    Henry, L; Kishimba, M A

    2006-03-01

    Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) samples were collected from fish landing stations in nine riparian districts on the Tanzanian side of Lake Victoria and screened for residues of 64 organochlorine, organophosphorus, carbamate, and pyrethroid pesticides. The residue levels in the fish fillet were up to 0.003, 0.03 and 0.2 mg/kg fresh weight (0.7, 3.8 and 42 mg/kg lipid weight) of fenitrothion, DDT and endosulfan, respectively. Mean levels within sites were up to 0.002, 0.02 and 0.1 mg/kg fresh weight (0.5, 0.5 and 16 mg/kg lipid weight), respectively. The detection of higher levels of p,p'-DDT than the degradation products (p,p'-DDD and p,p'-DDE), and higher levels of endosulfan isomers (alpha and beta) than the sulphate, in fish samples, implied recent exposure of fish to DDT and endosulfan, respectively. Generally, most of the fish samples had residue levels above the average method detection limits (MDLs), but were within the calculated ADI.

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

    PubMed

    Centner, Terence; Eberhart, Nicholas

    2014-05-08

    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.

  17. T-REX Version 1.5 User's Guide for Calculating Pesticide Residues on Avian and Mammalian Food Items - Appendix B - Initial Pesticide Residues on Arthropods

    EPA Pesticide Factsheets

    Obtain empirical data from the scientific literature and registrant-submitted studies to refine the initial residue assumptions of pesticides on arthropods that are simulated with TIM, T-REX, and T-HERPS

  18. 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

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

    PubMed

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

    2009-06-01

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

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

    PubMed

    Angioni, Alberto; Dedola, Fabrizio

    2013-05-01

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

  1. 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.

  2. 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.

  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. Removal of chloropyrifos ethyl, tetradifon and chlorothalonil pesticide residues from citrus by using ozone.

    PubMed

    Kusvuran, Erdal; Yildirim, Deniz; Mavruk, Funda; Ceyhan, Mehmet

    2012-11-30

    The removal of chloropyrifos ethyl, tetradifon and chlorothalonil pesticide residues from the lemon, orange and grapefruit matrices were achieved by ozonation. All of chlorothalonil residues adsorbed onto the orange matrix were completely removed after 5 min ozonation. The highest removal percentages of tetradifon and chloropyrifos ethyl were achieved as 98.6 and 94.2%, respectively for the lemon and grapefruit matrices. All of diffused chlorothalonil and chloropyrifos ethyl residues were completely removed from both orange and grapefruit matrices after 5 min ozonation. Increasing of applied ozone dosage was not significantly effect on the removal percentages of pesticides whereas increasing of ozonation temperature caused a negative effect on the removal percentages of pesticides. The washing of the matrices with tap water was not as effective as ozonation in the removal of residual pesticides. Our results show that ozone treatment has a great potential for removing of residual pesticides from lemon, orange and grapefruit matrices.

  5. 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.

  6. Streamlined pretreatment and GC-FPD analysis of multi-pesticide residues in perennial Morinda roots: a tropical or subtropical plant.

    PubMed

    Liu, Hongmei; Kong, Weijun; Qi, Yun; Gong, Bao; Miao, Qing; Wei, Jianhe; Yang, Meihua

    2014-01-01

    In this study, a simple and rapid multi-pesticide residues analytical method has been developed and evaluated for simultaneous identification and quantification of 30 organophosphorus pesticides (OPPs) present at trace levels in perennial Morinda roots. Samples were firstly extracted and cleaned up with a streamlined method (modified QuEChERS), and then detected by gas chromatography with flame photometric detector (GC-FPD). For accurate quantification, representative matrix-matched calibration curves were applied to compensate matrix effects. Reasonable linearity was found in the concentration ranges of 0.04 and 1.28 μg mL(-1), with correlation coefficients r better than 0.9921 (0.9921-0.9998). The limits of detection (LODs) were between 0.005 and 0.02 μg mL(-1) for all investigated pesticides, while the limits of quantification (LOQs) were in the range of 0.01-0.04 μg mL(-1), below the regulatory maximum residue limits (MRL) suggested. Acceptable quantitative recoveries of 75.01-118.89% (96.0% on average) were achieved with relative standard deviations (RSD) varying from 0.89% to 9.80% (5.39% on average) at three different concentration levels of 0.05, 0.1 and 1.0 mg kg(-1). Out of all 40 batches of real samples, only fenitrothion was found in two samples, which was successfully confirmed by GC-MS. Based on these results, this analytical method has been proven to be fast, robust, accurate, selective, sensitive and easy to operate in the analysis of multiple pesticide residues in Morinda roots. Meanwhile, it also draws attention to the need of pesticide monitoring programs in local soils.

  7. 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...

  8. [Simultaneous determination of pesticide residues in agricultural products by LC-MS/MS].

    PubMed

    Watanabe, Minae; Ueno, Eiji; Inoue, Tomomi; Ohno, Haruka; Ikai, Yoshitomo; Morishita, Toshio; Oshima, Harumi; Hayashi, Rumiko

    2013-01-01

    A method for the simultaneous determination of multiple pesticide residues in agricultural products was developed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The sample was extracted with acetonitrile. Co-extractives were removed by GPC/graphitized carbon column SPE, and silica gel/PSA cartridge column SPE. Pesticides in the test solution were determined by LC-MS/MS using scheduled MRM. Recoveries of 124 pesticides from spinach, brown rice, soybean, orange and tomato were tested at the level of 0.1 µg/g, and those of 121 pesticides ranged from 70 to 120% (RSD≤15%). Pesticide residues in 239 agricultural products were investigated by this method, and residues of 49 pesticides were detected in 98 agricultural products.

  9. 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...

  10. 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...

  11. 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...

  12. Automated determination of pesticide residues in olive oil by on-line reversed-phase liquid chromatography-gas chromatography using the through oven transfer adsorption desorption interface with electron-capture and nitrogen-phosphorus detectors operating simultaneously.

    PubMed

    Díaz-Plaza, Eva M; Cortés, Jose M; Vázquez, Ana; Villén, Jesús

    2007-12-07

    A rapid method for the multiresidue analysis of pesticides in olive oil is presented. Pesticides are analyzed by on-line coupling reversed-phase liquid chromatography-gas chromatography using the through oven transfer adsorption desorption (TOTAD) interface with subsequent simultaneous electron-capture and nitrogen-phosphorus detection by post-column splitter. An autosampler is employed and the olive oil is simply filtered before the chromatographic analysis. Organophosphorus, organochlorine and triazine pesticides are determined in one run. The limits of detection are below the required maximum residue levels and calibration curves are linear in the range tested. Repeatabilities (intra-day and inter-days) are good. The method was satisfactory applied to the routine analysis of numerous olive oil samples.

  13. Cloning and expression of ophB gene encoding organophosphorus hydrolase from endophytic Pseudomonas sp. BF1-3 degrades organophosphorus pesticide chlorpyrifos.

    PubMed

    Barman, Dhirendra Nath; Haque, Md Azizul; Islam, Shah Md Asraful; Yun, Han Dae; Kim, Min Keun

    2014-10-01

    Chlorpyrifos is an organophosphate pesticide that has adverse effect on animals and plants. We isolated endophytic bacterial strain, Pseudomonas sp. BF1-3, from balloon flower root which can hydrolyze chlorpyrifos. A gene (ophB) encoding a protein involved in chlorpyrifos degradation from this strain was cloned into Escherichia coli DH5α for confirming enzyme activity. After sequencing, total 1024bp nucleotide sequences were found in the open reading frame of ophB. The chlorpyrifos degradation patterns by E. coli DH5α (ophB) were observed. During incubation in minimal salt (M9) medium supplemented with chlorpyrifos (100mgL(-1)), the E. coli DH5α harboring ophB degraded about 97% initial chlorpyrifos (100mgL(-1)) and accumulated 86mgL(-1) 3,5,6-trichloro-2-pyridinol (TCP) within 9 days. In addition, optical density (OD) of E. coli DH5α (ophB) culture at 600nm was increased from 0.172 to 1.118 within 2 days of inoculation in the chlorpyrifos supplemented M9 medium. The estimated molecular weight of purified OphB protein was determined to be 31.4kDa by SDS-PAGE. The OphB enzyme was most active at pH 8 and an optimal temperature around 35°C. These results indicate that endophytic bacteria are supposed to be useful for biological control of environments contaminated with pesticides.

  14. Effect of ultraviolet-absorbing vinyl film on organophosphorus insecticides dichlorvos and fenitrothion residues in spinach.

    PubMed

    Amano, Shoko; Katami, Takeo; Shibamoto, Takayuki

    2002-07-01

    Dichlorvos and fenitrothion residues found in spinach grown in greenhouse covered either by regular vinyl film or UV-absorbing vinyl film (UV-A) were analyzed by gas chromatography. After one day, dichlorvos residues in spinach covered with regular vinyl film and UV-A degraded by 97% and 80%, respectively, and degraded 100% after three days covered with regular vinyl film and six days covered with UV-A. After three days, fenitrothion residue in spinach covered with regular vinyl film degraded by 72% and then by 97% after six days; residue in spinach covered with UV-A degraded by 50% after three days and by 95% after six days. These results indicate that UV-A used to prevent the occurrence of insects and fungi in greenhouses reduced the degradation rates of dichlorvos and fenitrothion.

  15. Limitations in the determination of maximum residue limits and highest residues of pesticides: Part I.

    PubMed

    Horváth, Zsuzsanna; Sali, Judit; Zentai, Andrea; Dorogházi, Enikő; Farkas, Zsuzsa; Kerekes, Kata; Ambrus, Árpád

    2014-01-01

    The pesticide usages are controlled by comparing residue concentrations in treated commodities to legally permitted maximum levels (MRLs) determined based on supervised trials designed to reflect likely maximum residues occurring in practice following authorised use. The number of trials available may significantly affect the accuracy of estimated maximum residues. We conducted a study with synthetic lognormal distributions with mean of 1 and standard deviations of 0.8 and 1.0, which reflect the residue distributions observed in practice. The likely residues in samples were modelled by drawing random samples of size 3, 5, 10 and 25 from the synthetic populations. The results indicate that the estimations of highest residues (HR), used for calculation of short-term intake, and the MRLs, serving as legal limits, are very uncertain based on 3-5 trials indicated by the calculated HR0.975/HR0.025 and MRL0.975/MRL0.025 ratios of 12 and 9, and 13 and 10, respectively, which question the suitability of such trials for the intended purpose. As the 95% range of HR and MRL rapidly decreases with number of trials, ideally ≥15 but minimum 6-8 trials should be used for estimation of HR and MRL according to the current typical practice of Codex Alimentarius.

  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. Determination of dialkyl phosphate metabolites of organophosphorus pesticides in human urine by automated solid-phase extraction, derivatization, and gas chromatography-mass spectrometry.

    PubMed

    Hemakanthi De Alwis, G K; Needham, Larry L; Barr, Dana B

    2008-01-01

    Organophosphorus (OP) pesticides are highly toxic but used commonly worldwide, nevertheless. Their urinary dialkylphosphate (DAP) metabolites are widely used for exposure assessment of OP pesticides in humans. We previously developed an analytical method to measure urinary DAPs utilizing solid-phase extraction (SPE)-derivatization-gas chromatography-tandem mass spectrometry (GC-MS-MS) with quantification using isotope-dilution technique. We now present a more cost-effective yet highly accurate method that can be easily adaptable to many laboratories for routine OP exposure assessment. This method is simple and fast and involves automated SPE of the metabolites followed by derivatization with pentafluorobenzyl bromide and quantification by GC-MS. Dibutyl phosphate (DBP) serves as the internal standard. The detection limits for the six metabolites ranged from 0.1 to 0.15 ng/mL. Depending on the metabolite the relative standard deviation of the analytical procedure was 2-15% for the metabolites. We compared performance of DBP as an internal standard with that of isotope-labeled compounds and found that DBP gives reliable results for the analytical procedure. We also optimized reaction parameters of pentafluorobenzylation.

  18. Plant uptake of pesticides and human health: dynamic modeling of residues in wheat and ingestion intake.

    PubMed

    Fantke, Peter; Charles, Raphaël; de Alencastro, Luiz Felippe; Friedrich, Rainer; Jolliet, Olivier

    2011-11-01

    Human intake of pesticide residues from consumption of processed food plays an important role for evaluating current agricultural practice. We take advantage of latest developments in crop-specific plant uptake modeling and propose an innovative dynamic model to estimate pesticide residues in the wheat-environment system, dynamiCROP. We used this model to analyze uptake and translocation of pesticides in wheat after foliar spray application and subsequent intake fractions by humans. Based on the evolution of residues in edible parts of harvested wheat we predict that between 22 mg and 2.1 g per kg applied pesticide are taken in by humans via consumption of processed wheat products. Model results were compared with experimentally derived concentrations in wheat ears and with estimated intake via inhalation and ingestion caused by indirect emissions, i.e. the amount lost to the environment during pesticide application. Modeled and measured concentrations in wheat fitted very well and deviate from less than a factor 1.5 for chlorothalonil to a maximum factor 3 for tebuconazole. Main aspects influencing pesticide fate behavior are degradation half-life in plant and time between pesticide application and crop harvest, leading to variations in harvest fraction of at least three orders of magnitude. Food processing may further reduce residues by approximately 63%. Intake fractions from residues in sprayed wheat were up to four orders of magnitude higher than intake fractions estimated from indirect emissions, thereby demonstrating the importance of exposure from consumption of food crops after direct pesticide treatment.

  19. Pesticide residues in orange fruit from citrus orchards in Nuevo Leon State, Mexico.

    PubMed

    Suárez-Jacobo, A; Alcantar-Rosales, V M; Alonso, D; Heras-Ramírez, M E; Elizarragaz-De La Rosa, D; Lugo-Melchor, O Y; Gaspar-Ramirez, O

    2017-04-04

    Some international organizations established Maximum Residue Limits (MRLs) in food to protect human health. Mexico lacks regulations in this matter, affecting national and international trade from agroindustry. The aim of this study was to diagnose pesticide residues in oranges from Nuevo Leon, México, in citrus orchards. In May 2014, 100 orange fruit samples were taken randomly from orchards and subjected to analysis for 93 pesticides at residual level by GC/QQQ-MS and LCQ-TOF-MS. Results showed presence of 15 pesticide residues in the samples. The comparison of the residual levels of pesticides found in orange samples among the MRLs allowed by USA, EU and Japanese regulations demonstrated that all samples were below MRLs issued by USA and Japan. Some orange samples were above MRLs issued by the EU. This provides a basis to establish strategies in order to satisfy International Standards to protect human health and encourage Food Safety in Mexico.

  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. 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.

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

    PubMed Central

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

    2008-01-01

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

  3. Multiple pesticide residues in live and poisoned honeybees - Preliminary exposure assessment.

    PubMed

    Kiljanek, Tomasz; Niewiadowska, Alicja; Gaweł, Marta; Semeniuk, Stanisław; Borzęcka, Milena; Posyniak, Andrzej; Pohorecka, Krystyna

    2017-02-08

    Study combines data about the exposure of honeybees to pesticides from plant protection products and veterinary medicinal products. Residues of 200 pesticide and pesticide metabolites in 343 live and 74 poisoned honeybee samples, obtained during the years of 2014-2015, were determined by LC-MS/MS and GC-MS/MS. In 44% of live honeybee 48 different pesticide residues were found, mainly amitraz metabolites (DMF, DMPF) and chlorpyrifos. In 98% of poisoned honeybee 57 pesticides and metabolites were detected, mainly chlorpyrifos, dimethoate and clothianidin. In total 84 different pesticides were detected both in live and poisoned honeybees, they indicate 30 various modes of action. Differences between mean number of pesticide residues detected in live and poisoned honeybees clearly indicate the impact of multiple pesticides on honeybee health. Possible impact of systemic fungicides on the health of honeybees was studied. Applicability of hazard quotient counted as ratio between concentration of pesticides in honeybees and lethal dose in the interpretation whether detected concentration indicates acute toxic effects was shown.

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

    NASA Astrophysics Data System (ADS)

    Andreou, Kostas; Semple, Kirk; Jones, Kevin

    2010-05-01

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

  5. 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...

  6. 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...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

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

    Code of Federal Regulations, 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...

  12. [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

  13. Pesticide residue dynamics in passion fruits: comparing field trial and modelling results.

    PubMed

    Juraske, Ronnie; Fantke, Peter; Ramírez, Ana Cecilia Romero; González, Alonso

    2012-10-01

    We evaluated the exposure to pesticides from the consumption of passion fruits and subsequent human health risks by combining several methods: (i) experimental field studies including the determination of pesticide residues in/on passion fruits, (ii) dynamic plant uptake modelling, and (iii) human health risk assessment concepts. Eight commonly used pesticides were applied onto passion fruits cultivated in Colombia. Pesticide concentrations were measured periodically (between application and harvest) in whole fruits and fruit pulp. Measured concentrations were compared with predicted residues calculated with a dynamic and crop-specific pesticide uptake model, namely dynamiCROP. The model accounts for the time between pesticide application and harvest, the time between harvest and consumption, the amount of spray deposition on plant surfaces, uptake processes, dilution due to crop growth, degradation in plant components, and reduction due to food processing (peeling). Measured and modelled residues correspond well (r(2)=0.88-0.99), with all predictions falling within the 90% confidence interval of the measured values. A mean error of 43% over all studied pesticides was observed between model estimates and measurements. The fraction of pesticide applied during cultivation that is eventually ingested by humans is on average 10(-4)-10(-6), depending on the time period between application and ingestion and the processing step considered. Model calculations and intake fractions via fruit consumption based on experimental data corresponded well for all pesticides with a deviation of less than a factor of 2. Pesticide residues in fruits measured at recommended harvest dates were all below European Maximum Residue Limits (MRLs) and therefore do not indicate any violation of international regulatory thresholds.

  14. 78 FR 1798 - Receipt of a Pesticide Petition Filed for Residues of Pesticide Chemicals in or on Various...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-09

    ... from the requirement of a tolerance in 40 CFR 180.1299 for residues of the plant growth regulator...: Gina Burnett, Biopesticides and Pollution Prevention Division (7511P), Office of Pesticide Programs... K. Reilly, Acting Director, Biopesticides and Pollution Prevention Division, Office of...

  15. Occurrence of pesticide non extractable residues in physical and chemical fractions from two natural soils.

    NASA Astrophysics Data System (ADS)

    Andreou, K.; Jones, K.; Semple, K.

    2009-04-01

    Distribution of pesticide non extractable residues resulted from the incubation of two natural soils with each of the isoproturon, diazinon and cypermethrin pesticide was assessed in this study. Pesticide non extractable residues distribution in soil physical and chemical fractions is known to ultimately affect their fate. This study aimed to address the fate and behaviour of the non extractable residues in the context of their association with soil physical and chemical fractions with varying properties and characteristics. Non extractable residues were formed from incubation of each pesticide in the two natural soils over a period of 24 months. Soils containing the non extractable residues were fractionated into three solid phase fractions using a physical fractionation procedure as follows: Sediment (SED, >20 μm), (II) Microaggregate (MA, 20-2 μm) and (III) Colloid phase (COL, 2-0.05 μm). Each soil fraction was then fractionated into organic carbon chemical fractionations as follows: Fulvic acid (FA), Humic acid (HA) and Humin (HM). Significant amount of the pesticides was lost during the incubation period. Enrichment factors for the organic carbon and the 14C-pesticide residues were higher in the MA and COL fraction rather than the SED fraction. Greater association and enrichment of the fulvic acid fraction of the organic carbon in the soil was observed. Non extractable residues at the FA fraction showed to diminish while in the HA fraction were increased with decreasing the fraction size. An appreciable amount of non extractable residues were located in the HM fraction but this was less than the amount recovered in the humic substances. Long term fate of pesticide non extractable residues in the soil structural components is important in order to assess any risk associated with them.

  16. Identification of the main pesticide residue mixtures to which the French population is exposed.

    PubMed

    Crépet, A; Tressou, J; Graillot, V; Béchaux, C; Pierlot, S; Héraud, F; Leblanc, J Ch

    2013-10-01

    Owing to the intensive use of pesticides and their potential persistence in the environment, various pesticide residues can be found in the diet. Consumers are therefore exposed to complex pesticide mixtures which may have combined adverse effects on human health. By modelling food exposure to multiple pesticides, this paper aims to determine the main mixtures to which the general population is exposed in France. Dietary exposure of 3337 individuals from the INCA2 French national consumption survey was assessed for 79 pesticide residues, based on results of the 2006 French food monitoring programmes. Individuals were divided into groups with similar patterns of co-exposure using the clustering ability of a Bayesian nonparametric model. In the 5 groups of individuals with the highest exposure, mixtures are formed by pairs of pesticides with correlations above 0.7. Seven mixtures of 2-6 pesticides each were characterised. We identified the commodities that contributed the most to exposure. Pesticide mixtures can either be components of a single plant protection product applied together on the same crop or be from separate products that are consumed together during a meal. Of the 25 pesticides forming the mixtures, two--DDT and Dieldrin--are known persistent organic pollutants. The approach developed is generic and can be applied to all types of substances found in the diet in order to characterise the mixtures that should be studied first because of their adverse effects on health.

  17. [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.

  18. 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.

  19. 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.

  20. [Investigation on the detection of pesticide residue in vegetable based on infrared spectroscopy].

    PubMed

    Li, Wen-xiu; Xu, Ke-xin; Wang, Yan; Lei, Zhen-lin; Zhang, Zhen-hou

    2004-10-01

    In this paper, the mid-infrared Attenuated Total Reflection (ATR) spectra of two slathered pesticides dichlorvos and trichlorfon in vegetable juice solution have been investigated. It can be concluded that within characteristic absorption region of the two pesticides in the mid-infrared range, the pigments inside the vegetable have no effect on the pesticide' s absorbance; pesticides in standard solution and vegetable juice solution share almost the same absorbance characteristics. These results indicate that: the authors can use the model built by the absorbance data of pesticides in water solution to simulate their absorbance in vegetable solution, then based upon infrared spectroscopy, the direct detection of pesticide residue on the vegetable can be achieved; it also provides a possible way of rapid detection on vegetable in the future.

  1. 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.

  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. Characteristics and alteration of pesticide residues in surface soils of agricultural fields and public parks

    NASA Astrophysics Data System (ADS)

    Al-Mutlaq, Khalid F.

    2006-12-01

    Organic contents of agricultural soils are major sources of organic compounds and pesticides into atmosphere. Therefore, surface soil samples from different locations in the city of Corvallis, USA were collected over a course of 1 year (2004/2005). The samples were subject to chemical extraction and analysis by gas chromatography-mass spectrometry (GC-MS). The results of the chemical analysis showed pesticide residues were present in soils and varied seasonally. For example, the highest total relative concentration of pesticide residues in Canola field was 0.16% in January 2005, and was 0.56% in Wheat Field in August 2005, and was 0.14% in the River Front Park in December 2004 and was 0.33 in Rose Garden. Sometimes in the year, these pesticide residues were not detected in the same sites.

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

    NASA Astrophysics Data System (ADS)

    Domagalski, Joseph L.; Dubrovsky, Neil 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.

  5. 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.

  6. Production of apple-based baby food: changes in pesticide residues.

    PubMed

    Kovacova, Jana; Kocourek, Vladimir; Kohoutkova, Jana; Lansky, Miroslav; Hajslova, Jana

    2014-01-01

    Apples represent the main component of most fruit-based baby food products. Since not only fruit from organic farming, but also conventionally grown fruit is used for baby food production, the occurrence of pesticide residues in the final product is of high concern. To learn more about the fate of these hazardous compounds during processing of contaminated raw material, apples containing altogether 21 pesticide residues were used for preparation of a baby food purée both in the household and at industrial scale (in the baby food production facility). Within both studies, pesticide residues were determined in raw apples as well as in final products. Intermediate product and by-product were also analysed during the industrial process. Determination of residues was performed by a sensitive multi-detection analytical method based on liquid or gas chromatography coupled with mass spectrometry. The household procedure involved mainly the cooking of unpeeled apples, and the decrease of residues was not extensive enough for most of the studied pesticides; only residues of captan, dithianon and thiram dropped significantly (processing factors less than 0.04). On the other hand, changes in pesticide levels were substantial for all tested pesticides during apple processing in the industrial baby food production facility. The most important operation affecting the reduction of residues was removal of the by-products after pulping (rest of the peel, stem, pips etc.), while subsequent sterilisation has an insignificant effect. Also in this case, captan, dithianon and thiram were identified as pesticides with the most evident decrease of residues.

  7. 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.

  8. Cloning of the organophosphorus pesticide hydrolase gene clusters of seven degradative bacteria isolated from a methyl parathion contaminated site and evidence of their horizontal gene transfer.

    PubMed

    Zhang, Ruifu; Cui, Zhongli; Zhang, Xiaozhou; Jiang, Jiandong; Gu, Ji-Dong; Li, Shunpeng

    2006-10-01

    Seven organophosphorus pesticide-degrading bacteria harboring the methyl parathion degrading (mpd) gene were isolated from a methyl parathion contaminated site. In this study, the 4.7 kb mpd gene cluster, conserved in all seven bacteria capable of degrading methyl parathion, was cloned and further analysis revealed that this cluster contained five ORFs and the mpd gene was associated with a mobile element, IS6100. In addition to mpd gene ORF and tnpA ORF, three other ORFs showed high homology to the permease component of ABC-type transport system, the general secretion pathway protein B, and the RNA polymerase sigma 70 factor, respectively. The mpd genes of these 7 strains were subcloned and expressed in E. coli, SDS-PAGE and zymogram analysis showed that two expression products of mpd genes in E. coli were found, but the one without signal peptide showed the hydrolytic activities. Our evidences collectively suggest that mpd gene cluster may be disseminated through horizontal gene transfer based on phylogenetic analysis of the cluster and their host bacterial strains, and comparisons of GC content of the cluster and respective host's chromosome.

  9. 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%.

  10. CODEX-compliant eleven organophosphorus pesticides screening in multiple commodities using headspace-solid phase microextraction-gas chromatography-mass spectrometry.

    PubMed

    Sang, Zi-Ye; Wang, Yu-Ting; Tsoi, Yeuk-Ki; Leung, Kelvin Sze-Yin

    2013-01-15

    A headspace-solid phase microextraction-gas chromatography-mass spectrometric (HS-SPME-GC-MS, hereafter abbreviated as "SPME") method was developed for dedicated organophosphorus (OP) pesticides assessment in multiple vegetable and fruit commodities. Specific extraction variables were optimised to achieve harmonised extraction performance of eleven OPs in a great span of seven characteristic commodities cataloged in Codex Alimentarius Commission. Comprehensive validation study confirmed analytical robustness of the SPME treatment in turnip, green cabbage, French beans, eggplant, apple, nectarine and grapes. Based on range-specific evaluation, extraction of individual OPs was characterised by sub-ppb level sensitivity and a wide 0.01-2.5 mg L(-1) dynamic range. Effective sample clean-up afforded precise quantification (0.5-10.9% R.S.D.) within a 70-120% recovery range at the MRL levels specified for individual commodities. Compared to conventional methods currently used, the SPME treatment developed here is quick, accurate, and relatively environmental friendly; it represents an attractive, practical way to deliver international standards in OP screening routines.

  11. Determination of organophosphorus pesticides in ecological textiles by solid-phase microextraction with a siloxane-modified polyurethane acrylic resin fiber.

    PubMed

    Hu, Xianlei; Zhang, Mingqiu; Ruan, Wenhong; Zhu, Fang; Ouyang, Gangfeng

    2012-07-29

    A novel solid-phase microextraction (SPME) fiber coating was prepared with siloxane-modified polyurethane acrylic resin by photo-cured technology. The ratio of two monomers was investigated to obtain good microphase separation structure and better extraction performance. The self-made fiber was then applied to organophosphorus pesticides (OPPs) analysis and several factors, such as extraction/desorption time, extraction temperature, salinity, and pH, were studied. The optimized conditions were: 15 min extraction at 25 °C, 5% Na(2)SO(4) content, pH 7.0 and 4 min desorption in GC inlet. The self-made fiber coating exhibited better extraction efficiency for OPPs, compared with three commercial fiber coatings. Under the optimized conditions, the detection limits of 11 OPPs were from 0.03 μg L(-1) to 0.5 μg L(-1). Good recoveries and repeatabilities were obtained when the method was used to determine OPPs in ecological textile.

  12. Polypyrrole/sol-gel composite as a solid-phase microextraction fiber coating for the determination of organophosphorus pesticides in water and vegetable samples.

    PubMed

    Saraji, Mohammad; Rezaei, Behzad; Boroujeni, Malihe Khalili; Bidgoli, Ali Akbar Hajialiakbari

    2013-03-01

    A novel solid-phase microextraction (SPME) fiber coated with polypyrrole/sol-gel composite was prepared through electrochemical deposition. The composite polymer coating was prepared using a three-electrode electrochemical system and directly deposited on a stainless steel wire by applying a constant potential (1.2V for 1000 s). The coating has porous surface structure, stable performance in high temperature, and good coating preparation reproducibility. The SPME composite coating was evaluated by analyzing some organophosphorus pesticides (OPPs) in water and vegetable samples followed by gas chromatography and nitrogen phosphorus detection. Different SPME parameters influencing the extraction efficiency such as coating thickness, salt concentration, stirring rate, extraction time and temperature, desorption time and desorption temperature were investigated. Under the optimized conditions, the coating showed better extraction efficiency than polypyrrole and commercial SPME fibers. The detection limits were 1.5-10 ng L(-1). Relative standard deviations for intra- and inter-day precision for a single fiber were in the range of 1.1-2.9% and 2.2-4.2%, respectively. Fiber to fiber reproducibility was in the range of 6.0-10.1% (n=3). The calibration curves were linear in the concentration range from 5 to 2000 ng L(-1) (r(2)>0.9953). Finally, the developed method was applied for the analysis of cucumber, lettuce, tap and well water samples and the relative recovery was found to be in the range of 80-109%, at the optimum conditions.

  13. 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

    2014-11-06

    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.

  14. Assessment of the efficacy of Artemia sp (Crustacea) cysts chorion as barrier to chlorpyrifos (organophosphorus pesticide) exposure. Effect on hatching and survival.

    PubMed

    Varó, I; Amat, F; Navarro, J C; Barreda, M; Pitarch, E; Serrano, R

    2006-07-31

    In order to reveal the efficacy of the Artemia cysts chorion as barrier to the organophosphorus pesticide chlorpyrifos, whole and decapsulated cysts have been exposed to 10 mg L(-1) chlorpyrifos in sea water during hydration and hatching phase, separately. The concentration of chlorpyrifos in capsulated and decapsulated cysts after exposure has been determined in order to elucidate the efficacy of chorion as protection to the embryo. The results obtained demonstrate the ability of the cysts chorion to obstruct the pass of chlorpyrifos molecules through this protection structure. Thus, the concentration of chlorpyrifos in exposed decapsulated cysts is higher than in exposed whole cysts. Moreover, after removing the chorion of exposed cysts, the concentration of chlorpyrifos in the embryo was lower than that of cysts exposed, what would demonstrate the retention of chlorpyrifos molecules by the shell. Hatching was not severely affected by exposure to the insecticide whereas survival at 44 h of the nauplii exposed to chlorpyrifos was significantly different from the controls. Survival of nauplii hatched from exposed decapsulated cysts was higher than that from those hatched from exposed whole cysts, probably because of the lower vitality of the latter, due to depletion of energy reserves during hatching.

  15. 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.

  16. 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.

  17. 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%.

  18. 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.

  19. Coprecipitation-assisted coacervative extraction coupled to high-performance liquid chromatography: An approach for determining organophosphorus pesticides in water samples.

    PubMed

    Mammana, Sabrina B; Berton, Paula; Camargo, Alejandra B; Lascalea, Gustavo E; Altamirano, Jorgelina C

    2017-02-08

    An analytical methodology based on coprecipitation-assisted coacervative extraction coupled to HPLC-UV was developed for determination of five organophosphorus pesticides (OPPs), including fenitrothion, guthion, parathion, methidathion, and chlorpyrifos, in water samples. It involves a green technique leading to an efficient and simple analytical methodology suitable for high-throughput analysis. Relevant physicochemical variables were studied and optimized on the analytical response of each OPP. Under optimized conditions, the resulting methodology was as follows: an aliquot of 9 mL of water sample was placed into a centrifuge tube and 0.5 mL sodium citrate 0.1 M, pH 4; 0.08 mL Al2 (SO4 )3 0.1 M; and 0.7 mL SDS 0.1 M were added and homogenized. After centrifugation the supernatant was discarded. A 700 μL aliquot of the coacervate-rich phase obtained was dissolved with 300 μL of methanol and 20 μL of the resulting solution was analyzed by HPLC-UV. The resulting LODs ranged within 0.7-2.5 ng/mL and the achieved RSD and recovery values were <8% (n = 3) and >81%, respectively. The proposed analytical methodology was successfully applied for the analysis of five OPPs in water samples for human consumption of different locations of Mendoza.

  20. Determination of organophosphorus pesticides using dispersive liquid-liquid microextraction combined with reversed electrode polarity stacking mode-micellar electrokinetic chromatography.

    PubMed

    Soisungnoen, Phimpha; Burakham, Rodjana; Srijaranai, Supalax

    2012-08-30

    A rapid and sensitive method using two preconcentration techniques, dispersive liquid-liquid microextraction (DLLME) followed by reversed electrode polarity stacking mode (REPSM) was developed for the analysis of five organophosphorus pesticides (OPPs) by micellar electrokinetic chromatography (MEKC). Parameters that affect the efficiency of the extraction in DLLME and preconcentration by REPSM, such as the kind and volume of the extraction and disperser solvents, salt addition, sample matrix and injection time were investigated and optimized. Under the optimum conditions, the enrichment factors were obtained in the range from 477 to 635. The linearity of the method for parathion, azinphos and fenitrithion was in the range of 20-1000 ng mL(-1), and for malathion and diazinon in the range of 50-1000 ng mL(-1), with correlation coefficients (r(2)) ranging from 0.9931 to 0.9992. The limits of detecton (LODs) at a signal-to-noice ratio of 3 ranged from 3 to 15 ng mL(-1). The relative recoveries of five OPPs from water samples at spiking levels of 20 and 200 ng mL(-1) for parathion, azinphos and fenitrithion, and 50 and 500 ng mL(-1) for malathion and diazinon, were 69.5-103%. The proposed method provided high enrichment factors, good precision and accuracy with a short analysis time.

  1. 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.

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

    PubMed

    Barata, Carlos; Solayan, Arun; Porte, Cinta

    2004-02-10

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

  3. 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.

  4. 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.

  5. 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

  6. 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 requirements table. 158.2130 Section 158.2130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... this table to determine the residue chemistry data requirements and the substance to be tested for...

  7. 40 CFR 158.2172 - Experimental use permit 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 Experimental use permit microbial pesticides residue data requirements table. 158.2172 Section 158.2172 Protection of Environment ENVIRONMENTAL.... Sections 158.100 through 158.130 describe how to use this table to determine the residue chemistry...

  8. 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...

  9. Monitoring and Risk Assessment of Pesticide Residues in Commercially Dried Vegetables

    PubMed Central

    Seo, Young-Ho; Cho, Tae-Hee; Hong, Chae-Kyu; Kim, Mi-Sun; Cho, Sung-Ja; Park, Won-Hee; Hwang, In-Sook; Kim, Moo-Sang

    2013-01-01

    We tested for residual pesticide levels in dried vegetables in Seoul, Korea. A total of 100 samples of 13 different types of agricultural products were analyzed by a gas chromatography-nitrogen phosphate detector (GC-NPD), an electron capture detector (GC-μECD), a mass spectrometry detector (GC-MSD), and a high performance liquid chromatography-ultraviolet detector (HPLC-UV). We used multi-analysis methods to analyze for 253 different pesticide types. Among the selected agricultural products, residual pesticides were detected in 11 samples, of which 2 samples (2.0%) exceeded the Korea Maximum Residue limits (MRLs). We detected pesticide residue in 6 of 9 analyzed dried pepper leaves and 1 sample exceeded the Korea MRLs. Data obtained were then used for estimating the potential health risks associated with the exposures to these pesticides. The estimated daily intakes (EDIs) range from 0.1% of the acceptable daily intake (ADI) for bifenthrin to 8.4% of the ADI for cadusafos. The most critical commodity is cadusafos in chwinamul, contributing 8.4% to the hazard index (HI). This results show that the detected pesticides could not be considered a serious public health problem. Nevertheless, an investigation into continuous monitoring is recommended. PMID:24471124

  10. Studies on organochlorine pesticide residue in fishes from the Densu river basin, Ghana.

    PubMed

    Kuranchie-Mensah, Harriet; Yeboah, Philip O; Nyarko, Elvis; Golow, Abledze A

    2013-04-01

    The study was carried out to determine the levels of organochlorine pesticide residue in five fish species Chrysichthys nigrodigitatus, Hepsetus odoe, Tilapia zilli, Heterotis niloticus and Oreochromis niloticus from the Densu river basin (Weija) in Ghana. The fishes sampled from the Weija fish landing site were selected on the basis of their importance to local human fish consumption. The detectable organochlorine pesticides were γ-Hexachlorocyclohexane (HCH), δ-Hexachlorocyclohexane, aldrin and dieldrin. Others investigated were alpha endosulfan, endosulfan sulfate, p,p'-DDT and its metabolite p,p'-DDE, endrin and its metabolite endrin aldehyde and endrin ketone. The total contamination levels of the individual fishes varied in the decreasing order of 9.19 ng g(-1) (O. niloticus), 4.16 ng g(-1) (T. zilli), 3.69 ng g(-1) (C. nigrodigitatus), 3.68 ng g(-1) (H. odoe) and 3.09 ng g(-1) (H. niloticus). The highest organochlorine pesticide residue recorded in the study was alpha-endosulfan while dieldrin was the least pesticide observed. Analysis of variance indicated significant statistical differences for most organochlorine pesticide residues in the samples. The levels of organochlorine pesticides found in fish samples in the study were below maximum residue limit for food safety stipulated by EU, US FDA, FAO, Italy and Australia and thus safe for human consumption.

  11. Reduction of pesticide residues on fresh vegetables with electrolyzed water treatment.

    PubMed

    Hao, Jianxiong; Wuyundalai; Liu, Haijie; Chen, Tianpeng; Zhou, Yanxin; Su, Yi-Cheng; Li, Lite

    2011-05-01

    Degradation of the 3 pesticides (acephate, omethoate, and dimethyl dichloroviny phosphate [DDVP]) by electrolyzed water was investigated. These pesticides were commonly used as broad-spectrum insecticides in pest control and high-residual levels had been detected in vegetables. Our research showed that the electrolyzed oxidizing (EO) water (pH 2.3, available chlorine concentration:70 ppm, oxidation-reduction potential [ORP]: 1170 mV) and the electrolyzed reducing (ER) water (pH 11.6, ORP: -860 mV) can reduce the pesticide residues effectively. Pesticide residues on fresh spinach after 30 min of immersion in electrolyzed water reduced acephate by 74% (EO) and 86% (ER), omethoate by 62% (EO) and 75% (ER), DDVP by 59% (EO) and 46% (ER), respectively. The efficacy of using EO water or ER water was found to be better than that of using tap water or detergent (both were reduced by more than 25%). Besides spinach, the cabbage and leek polluted by DDVP were also investigated and the degradation efficacies were similar to the spinach. Moreover, we found that the residual level of pesticide residue decreased with prolonged immersion time. Using EO or ER water to wash the vegetables did not affect the contents of Vitamin C, which inferred that the applications of EO or ER water to wash the vegetables would not result in loss of nutrition.

  12. [Study of pesticide residues in agricultural products for the "Positive List" system].

    PubMed

    Akiyama, Yumi; Yoshioka, Naoki; Ichihashi, Keiko

    2005-12-01

    During a 3-year monitoring survey (April 2002-March 2005) of pesticide residues in agricultural products, 592 samples (324 domestic; 268 imported) collected in Hyogo prefecture, Japan were analyzed. The number of pesticides tested increased from 232 in FY 2002 to 323 in FY 2004. The purpose of the study was to clarify the residue status by accumulating information about pesticides detected frequently, to allow effective and efficient regulation under the new "Positive List" legislation to be implemented in FY 2006. Overall, 47% of domestic and 61% of imported samples contained detectable residues and ca. 60% of positive samples contained multiple residues. The limit of quantitation was set at 0.01 microg/g and the limit of detection was 0.001-0.003 microg/ g. Most of the residues were present at low concentrations: 80% of the detections in samples excluding imported citrus fruits were < 0.05 microg/g. More than 5 different pesticides (> 0.01 microg/g) were detected simultaneously in 13 samples. The sum of the ratios of residues to MRLs was calculated as one of the indexes to represent the risk of multiple residues, and they exceeded 100% in 3 imported frozen vegetables; baby kidney bean, spinach, Welsh onion. Samples in violation of the Food Sanitation Law were not found in our survey, but 1.9% of the samples might be in conflict with the new "Positive List" legislation.

  13. Risk assessment of oncogenic potency of pesticide residues in fruits and vegetables.

    PubMed

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

    2011-01-01

    Pesticides are used in agriculture to improve food security by assuring good harvest, however, they can have harmful effects in human beings and animals. One of the harmful effects of pesticides is their carcinogenicity. Exposure to oncogenic compounds may result in cancer to the exposed animal or person. In this paper, exposure assessment of oncogenic potency of pesticides was performed from raw and processed fruits and vegetables. The oncogenic risk was calculated by multiplying the estimated daily intake (EDI) of the pesticide residue with the oncogenic potency factor (Q*) of the concerned pesticide. The total potential oncogenic risk was calculated to be 2.76 x 10(-3) before processing and 8.97 x 10(-4) after processing. The risk was higher than the EPA acceptable limit of 1 x10(-6). Despite the calculated levels exceeding the EPA acceptable limit, food processing activities reduced the dietary oncogenic risk to an average 33.8%.

  14. 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.

  15. Organochlorine pesticide residues in fish from southern Italian rivers

    SciTech Connect

    Amodio-Cocchieri, R.; Arnese, A.

    1988-02-01

    Extensive use of pesticides in agricultural and municipal fields contributed all over the world to an effective increase of production and to a limitation of the vector injuries to health. However the large quantities of synthetic chemical products employed to achieve these purposes have resulted in an extended environmental pollution, especially worrying about the organochlorine insecticides that are very persistent and suspected of carcinogenicity. For these reasons, this group of pesticides has been banned or strongly restricted in many countries including Italy, where just Lindane and Endosulfan are now allowed in agriculture, representing only 7% of the annual use of synthetic pesticides. In order to control the amount of contamination of surface water from organochlorine pesticides, some surveys were carried out in northern and central Italy, but information regarding situation in southern Italy is not available. The purpose of this study was to evaluate the occurrence and the magnitude of chlorinated pesticide aquatic pollution in southern Italy by the analysis of some permanent freshwater fish species.

  16. Rapid Multi-Residue Analysis of Pesticides in Pulses by LC-MS/MS.

    PubMed

    Iwakoshi, Keiko; Otsuka, Kenji; Tamura, Yasuhiro; Tomizawa, Sanae; Masubuchi, Tamako; Yamaki, Yumiko; Nakagawa, Yukiko; Masuda, Ryoko; Suto, Shota; Kokaji, Yoshie; Shindo, Tetsuya; Takano, Ichiro

    2016-01-01

    Rapid multi-residue analysis of pesticides in pulses was developed using LC-MS/MS. Pesticide residues in 5 g of homogenized pulses were extracted with 30 mL of acetonitrile and salted out with 4 g of anhydrous magnesium sulfate and 2 g of sodium chloride in the presence of citrate buffer in a disposable tube. The resulting residues were extracted with 30 mL of acetonitrile, and co-extractives were removed on a handmade four-layer column, consisting of a layer of Z-Sep/C18 (20 mg/50 mg) dry particles on top of a three-layer, custom-made (pre-packed) column (lower bed: 60 mg of PSA, middle bed: 30 mg of GC, and top bed: 60 mg of C18) packed in a 10 mm internal diameter polypropylene column (3 mL). The developed method showed good recoveries of pesticides in soybean, lentil, white kidney bean and garbanzo. According to the method validation guideline of the Ministry of Health, Labour and Welfare of Japan, recovery tests were conducted in soybeans fortified with 107 kinds of pesticides at the levels of 0.01 and 0.1 μg/g, respectively. At each concentration 2 samples were extracted on 5 separate days. Pesticides in the test solution were determined by LC-MS/MS using scheduled MRM. As regards the trueness of this method for 107 pesticides in soybeans, 97 pesticides were in the range of 70-120% with satisfactory repeatability and within-run reproducibility. This new method is expected to be applicable for routine examination of pesticide residues in soybeans.

  17. 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

  18. Neonicotinoids transference from the field to the hive by honey bees: Towards a pesticide residues biomonitor.

    PubMed

    Silvina, Niell; Florencia, Jesús; Nicolás, Pérez; Cecilia, Pérez; Lucía, Pareja; Abbate, Silvana; Leonidas, Carrasco-Letelier; Sebastián, Díaz; Yamandú, Mendoza; Verónica, Cesio; Horacio, Heinzen

    2017-03-01

    The beehive as a quantitative monitor of pesticide residues applied over a soybean crop was studied through a semi field experiment of controlled exposure of honey bees to pesticides in macro tunnels. The distribution within exposed beehives of pesticides commonly used in soybean plantation, was assessed. Residue levels of insecticides in soybean leaves, honey bees, wax, honey and pollen were analyzed. The transference from pesticides present in the environment into the beehive was evidenced. The obtained results allow relating pesticide concentrations present in the environment with traces found in foraging bees. Therefore, pesticide transference ratios could be calculated for each detected compound (acetamiprid, imidacloprid and thiamethoxam) which showed a linear inverse trend with their 1-octanol/water partition coefficient (Kow). The least transferred pesticide to the hive (acetamiprid) has the highest vapor pressure (Vp). This study gives new insights on the usefulness of monitoring the environment through beehives aiming to evaluate if agroecosystems remain sustainable. It also contributes to generate valuable information for model building aiming to predict environmental quality through beehive's analysis.

  19. 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.

  20. 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.

  1. 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

  2. "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

  3. Pesticide residue analysis of vegetables by gas chromatography with electron-capture detection.

    PubMed

    Fenoll, José; Hellín, Pilar; Martínez, Carmen M; Flores, Pilar

    2007-01-01

    A new and original analytical method was developed for the routine analysis of 28 multiclass pesticide residues in vegetables (green pepper, red pepper, and tomato). The extraction was performed with acetone, and the pesticides were partitioned into ethyl acetate-cyclohexane (1 + 1, v/v). Residue levels in vegetables were determined by gas chromatography (GC) with electron-capture detection. Residue identities were confirmed by GC coupled with mass spectrometry in the selected ion monitoring mode. The average recoveries in pepper and tomato obtained for all analytes studied were 67.3 and 123.1%, respectively, with relative standard deviation between 1.8 and 7.0%. The detection limit for the pesticides studied varied from 0.1 to 2.6 microg/kg. The proposed method was applied to the analysis of these compounds in vegetables grown in experimental greenhouses.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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

  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.

  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.

  11. [Simultaneous analysis of residual pesticides in fruit, vegetables, brown rice, and oolong tea by LC-MS/MS].

    PubMed

    Namikawa, Mikio; Shibata, Sayo; Shiomi, Tetsuo; Nakagawa, Tomoyuki; Ban, Soichiro; Tomita, Yoko; Semura, Shunsuke; Nakao, Yoshie; Banno, Yukinori; Kawakami, Masahiro

    2014-01-01

    According to "The validity evaluation guideline of the testing methodology on the residual pesticides in food" of the Ministry of Health, Labour and Welfare of Japan, we carried out validity evaluation of a simultaneous analysis method for residual pesticides in various products with the QuEChERS method using a C18 mini column and/or an EnviCarb/PSA mini column for purification. Multi-ingredient simultaneous analysis with high sensitivity in a short time was achieved with LC-MS/MS. Validation was achieved for 269 pesticides among 302 pesticides in eight kinds of fruit, vegetables, and brown rice and 204 pesticides among 233 pesticides in oolong tea. Finally, 151 pesticides in oolong tea and from 234 to 259 pesticides in fruit, vegetables, and brown rice met the values specified in the guideline.

  12. 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

  13. 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.

  14. Effective adsorption and enhanced removal of organophosphorus pesticides from aqueous solution by Zr-based MOFs of UiO-67.

    PubMed

    Zhu, Xiangyang; Li, Bing; Yang, Jian; Li, Yongsheng; Zhao, Wenru; Shi, Jianlin; Gu, Jinlou

    2015-01-14

    Though many efforts have been devoted to the adsorptive removal of hazardous materials of organophosphorus pesticides (OPs), it is still highly desirable to develop novel adsorbents with high adsorption capacities. In the current work, the removal of two representative OPs, glyphosate (GP) and glufosinate (GF), was investigated by the exceptionally stable Zr-based MOFs of UiO-67. The abundant Zr-OH groups, resulting from the missing-linker induced terminal hydroxyl groups and the inherent bridging ones in Zr-O clusters of UiO-67 particles, served as natural anchorages for efficient GP and GF capture in relation with their high affinity toward phosphoric groups in OPs. The correlation between the most significant parameters such as contact time, OPs concentration, adsorbent dose, pH, as well as ionic strength with the adsorption capacities was optimized, and the effects of these parameters on the removal efficiency of GP and GF from the polluted aqueous solution were investigated. The adsorption of GP on UiO-67 was faster than that of GF, and a pseudo-second-order rate equation effectively described the uptake kinetics. The Langmuir model exhibited a better fit to adsorption isotherm than the Freundlich model. Thanks to the strong affinity and adequate pore size, the adsorption capacities in UiO-67 approached as high as 3.18 mmol (537 mg) g(-1) for GP and 1.98 mmol (360 mg) g(-1) for GF, which were much higher than those of many other reported adsorbents. The excellent adsorption characteristics of the current adsorbents toward OPs were preserved in a wide pH window and high concentration of the background electrolytes. These prefigured the promising potentials of UiO-67 as novel adsorbent for the efficient removal of OPs from aqueous solution.

  15. 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

    2014-12-05

    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.

  16. An ultra-sensitive acetylcholinesterase biosensor based on reduced graphene oxide-Au nanoparticles-β-cyclodextrin/Prussian blue-chitosan nanocomposites for organophosphorus pesticides detection.

    PubMed

    Zhao, Haiyan; Ji, Xueping; Wang, Beibei; Wang, Na; Li, Xianrui; Ni, Ruixing; Ren, Jujie

    2015-03-15

    This work reports a novel, ultrasensitive, and selective sensing platform based on a direct electrodeposition of electrochemical reduced graphene oxide (ERGO)-Au nanoparticles (AuNPs)-β-cyclodextrin (β-CD) and Prussian blue-chitosan (PB-CS) on glass carbon electrode (GCE) for efficiently fixed acetylcholinesterase (AChE) to fabricate organophosphorus pesticides (OPs) biosensor. The PB-CS not only effectively catalyzed the oxidation of thiocholine (TCh), but also shifted its oxidation potential from 0.68 to 0.2V, and accordingly the sensitivity of the biosensor was obviously improved. The synergistic effect between ERGO and AuNPs significantly promoted the electron transfer between PB and GCE, and remarkably enhanced the electrochemical oxidation of TCh. Besides, β-CD could interact with substrate by reversible bonding, which is contribute to increase the enrichment of the substrate and improve the selectivity and sensitivity of the biosensor. The integration of ERGO-AuNPs-β-CD with PB-CS provided an advantageous and high-performance platform for sensing applications. Based on the inhibition of OPs on AChE activity, the sensor showed wide linear ranges of 7.98-2.00×10(3)pgmL(-1) and 4.3-1.00×10(3)pgmL(-1) with low detection limits of 4.14pgmL(-1) and 1.15pgmL(-1) for malathion and carbaryl, respectively. The proposed biosensor exhibited short response time, good stability and high sensitivity, which can be used for direct analysis of practical samples.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Ionic liquid-based dispersive liquid-liquid microextraction followed high-performance liquid chromatography for the determination of organophosphorus pesticides in water sample.

    PubMed

    He, Lijun; Luo, Xianli; Xie, Hongxue; Wang, Chunjian; Jiang, Xiuming; Lu, Kui

    2009-11-23

    Using 1-octyl-3-methylimidazolium hexafluorophosphate ([C(8)MIM][PF(6)]) ionic liquid as extraction solvent, organophosphorus pesticides (OPPs) (parathion, phoxim, phorate and chlorpyifos) in water were determined by dispersive liquid-liquid microextraction (DLLME) combined with high-performance liquid chromatography (HPLC). The extraction procedure was induced by the formation of cloudy solution, which was composed of fine drops of [C(8)MIM][PF(6)] dispersed entirely into sample solution with the help of disperser solvent (methanol). Parameters including extraction solvent and its volume, disperser solvent and its volume, extraction time, centrifugal time, salt addition, extraction temperature and sample pH were investigated and optimized. Under the optimized conditions, up to 200-fold enrichment factor of analytes and acceptable extraction recovery (>70%) were obtained. The calibration curves were linear in the concentration range of 10.5-1045.0 microg L(-1) for parathion, 10.2-1020.0 microg L(-1) for phoxim, 54.5-1089.0 microg L(-1) for phorate and 27.2-1089.0 microg L(-1) for chlorpyifos, respectively. The limits of detection calculated at a signal-to-noise ratio of 3 were in the range of 0.1-5.0 microg L(-1). The relative standard deviations for seven replicate experiments at 200 microg L(-1) concentration level were less than 4.7%. The proposed method was applied to the analysis of four different sources water samples (tap, well, rain and Yellow River water) and the relative recoveries of spiked water samples are 99.9-115.4%, 101.8-113.7% and 87.3-117.6% at three different concentration levels of 75, 200 and 1000 microg L(-1), respectively.

  2. Determination of pesticide residues in fruits and vegetables in Islamabad market.

    PubMed

    Tahir, S; Anwar, T; Ahmad, I; Aziz, S; Mohammad, A; Ahad, K

    2001-01-01

    Pesticide residues in fruits and vegetable from Islamabad market, Pakistan were determined by GLC using Perkin Elmer Autosystem equipped with 63NECD and capillary column. Dimethoate was determined in the quantity of 0.032 mg kg-1 in apple, 0.110 mg kg-1 in banana, 0.004 mg kg-1 in brinjal, 1.80 mg kg-1 in cauliflower and 0.13 mg kg-1 in arvi, fenvalerate 0.010 mg kg-1 in apple and chlorpyrifos 0.004 mg kg-1 in brinjal. The importance of these pesticide residues with reference to human health is also briefly discussed.

  3. 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

  4. Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds.

    PubMed

    Letort, Sophie; Balieu, Sébastien; Erb, William; Gouhier, Géraldine; Estour, François

    2016-01-01

    The aim of this review is to provide an update on the current use of cyclodextrins against organophosphorus compound intoxications. Organophosphorus pesticides and nerve agents play a determinant role in the inhibition of cholinesterases. The cyclic structure of cyclodextrins and their toroidal shape are perfectly suitable to design new chemical scavengers able to trap and hydrolyze the organophosphorus compounds before they reach their biological target.

  5. 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

  6. In vitro skin decontamination of the organophosphorus pesticide Paraoxon with nanometric cerium oxide CeO2.

    PubMed

    Salerno, Alicia; Devers, Thierry; Bolzinger, Marie-Alexandrine; Pelletier, Jocelyne; Josse, Denis; Briançon, Stéphanie

    2017-04-01

    Organophosphorus compounds (OP), which mainly penetrate via the percutaneous pathway, represent a threat for both military and civilians. Body surface decontamination is vital to prevent victims poisoning. The development of a cost-effective formulation, which could be efficient and easy to handle in case of mass contamination, is therefore crucial. Metal oxides nanoparticles, due their large surface areas and the large amount of highly reactive sites, present high reactivity towards OP. First, this study aimed at evaluating the reaction of CeO2 nanoparticles, synthetized by microwave path and calcined at 500 or 600 °C, with Paraoxon (POX) in aqueous solution. Results showed that both nanoparticles degraded 60%-70% of POX. CeO2 calcined at 500 °C, owing to its larger specific area, was the most effective. Moreover, the degradation was significantly increased under Ultra-Violet irradiation (initial degradation rate doubled). Then, skin decontamination was studied in vitro using the Franz cell method with pig-ear skin samples. CeO2 powder and an aqueous suspension of CeO2 (CeO2-W) were applied 1 h after POX exposure. The efficiency of decontamination, including removal and/or degradation of POX, was compared to Fuller's earth (FE) and RSDL lotion which are, currently, the most efficient systems for skin decontamination. CeO2-W and RSDL were the most efficient to remove POX from the skin surface and decrease skin absorption by 6.4 compared to the control not decontaminated. FE reduced significantly (twice) the absorbed fraction of POX, contrarily to CeO2 powder. Considering only the degradation rate of POX, the products ranged in the order CeO2 > RSDL > CeO2-W > FE (no degradation). This study showed that CeO2 nanoparticles are a promising material for skin decontamination of OP if formulated as a dispersion able to remove POX like CeO2-W and to degrade it as CeO2 powder.

  7. Effect of Cooking Process on the Residues of Three Carbamate Pesticides in Rice

    PubMed Central

    Shoeibi, Shahram; Amirahmadi, Maryam; Yazdanpanah, Hassan; Pirali-Hamedani, Morteza; Pakzad, Saied Reza; Kobarfard, Farzad

    2011-01-01

    A gas chromatography mass spectrometry with spike calibration curve method was used to quantify three carbamate pesticides residue in cooked white rice and to estimate the reduction percentage of the cooking process duration. The selected pesticides are three carbamate pesticides including carbaryl and pirimicarb that their MRL is issued by “The Institute of Standards of Iran” and propoxur which is used as a widely consumed pesticide in rice. The analytical method entailed the following steps: 1- Blending 15 g cooked sample with 120 mL acetonitrile for 1 min in solvent proof blender, 2- Adding 6 g NaCl and blending for 1 min, 3- Filtering upper layer through 25 g anhydrous Na2SO4, 4- Cleaning up with PSA and MgSO4, 5- Centrifuging for 7 min, 6- Evaporating about 0.3 mL and reconstituting in toluene till 1 mL, 7- Injecting 2 μL extract into GC/MS and analyzing by single quadruple selected ion monitoring GC/MS-SQ-SIM. The concentration of pesticides and the percentage of pesticides amounts after the cooking were determined by gas chromatography mass-spectrometry (GC/MS) using with interpolation of the relative peak areas for each pesticide to internal standard peak area in the sample on the spiked calibration curve. Calibration curve was linear over the range of 25 to 1000 ng/g, and LOQ was 25 ng/g for all three pesticides. The percent of loss for the three pesticides were 78%, 55% and 35% for carbaryl, propoxur and pirimicarb respectively. Different parameters such as vapor pressure, boiling point, and suspect ability of the compound to hydrolysis, could be responsible for the losing of pesticides during the cooking process. PMID:24363690

  8. 75 FR 1773 - Notice of Receipt of a Pesticide Petition Filed for Residues of Polymeric Polyhydroxy Acid in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... AGENCY Notice of Receipt of a Pesticide Petition Filed for Residues of Polymeric Polyhydroxy Acid in or... establishment of a regulation for residues of the plant growth regulator, polymeric polyhydroxy acid, in or on... polymeric polyhydroxy acid in or on all food commodities. EPA has determined that the pesticide...

  9. Residue levels and risk assessment of pesticides in nuts of China.

    PubMed

    Liu, Yihua; Shen, Danyu; Li, Shiliang; Ni, Zhanglin; Ding, Ming; Ye, Caifen; Tang, Fubin

    2016-02-01

    The pesticide residue levels of three nuts (chestnut, walnut, pinenut) collected from seven main producing areas of China were investigated. Twenty-nine pesticides, including organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and two fungicides (triadimefon and buprofezin) were analyzed by gas chromatography (GC). Four OPs (acephate, dimethoate, chlorpyrifos and parathion-methyl) were found in 11.4% samples, with the concentrations of 19.0 µg kg(-1) to 74.0 µg kg(-1). Six OCs (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) were found in 18.2% samples, with the concentrations of 2.0 µg kg(-1) to 65.7 µg kg(-1). Among OCs, p,p-DDE and α-HCH were the dominant isomer for DDT and HCH. Five PYs (fenpropathrin, fenvalerate, cypermethrin, bifenthrin and cyhalothrin) were found in 15.9% samples, with the concentrations of 2.5 µg kg(-1) to 433.0 µg kg(-1). Fenpropathrin was the most frequently detected pesticide. In addition, triadimefon and buprofezin were detected only in two samples. For the tested nuts, 25.0% samples with multiple residues (containing more than two pesticides) were noted, even up to 9.1% samples with five pesticide residues. The residue of 15.9% samples was higher than the maximum residue limits (MRLs) of China. The short-term risks for the tested nuts were below 1.2%, and the highest long-term risk was 12.58%. The cumulative risk (cHI) for the tested pesticides were 8.43% (OPs), 0.42% (OCs), 12.82% (PYs) and 0.15% (fungicides), respectively. The total cHI was 21.82%. There was no significant health risk for consumers via nuts consumption.

  10. Use of semipermeable membrane devices (SPMDS) to determine bioavailable organochlorine pesticide residues in streams receiving irrigation drainwater

    USGS Publications Warehouse

    Petty, Jimmie D.; Huckins, James N.; Martin, D.B.; Adornato, T.G.

    1995-01-01

    The semipermeable membrane device (SPMD), consisting of a neutral lipid (triolein) enclosed in polyethylene layflat tubing, is very effective in sequestering bioavailable organochlorine (OC) pesticides in the environment. We used SPMDs to sequester OC pesticide residues in streams receiving irrigation drainwater and found toxaphene, the DDT complex, dieldrin, and endrin. Ambient water concentrations of the OC pesticides were calculated using an algorithm developed previously. Toxaphene residues were estimated to range from 300 to 7,000 ng/L.

  11. Determination of organochlorine pesticide residue in sediment and water from the Densu river basin, Ghana.

    PubMed

    Kuranchie-Mensah, Harriet; Atiemo, Sampson Manukure; Palm, Linda Maud Naa-Dedei; Blankson-Arthur, Sarah; Tutu, Anita Osei; Fosu, Paul

    2012-01-01

    The distribution of organochlorine pesticides in the aquatic ecosystem from the Densu river revealed varying levels of concentration in water and the sediment samples. Three locations were sampled along the river to evaluate the levels of organochlorine pesticide residue in the river. Sediment and surface water samples were extracted by soxhlet and liquid-liquid extraction respectively and analyzed using Gas Chromatograph coupled with electron capture detector. The detectable organochlorine pesticides were gamma-hexachlorocyclohexane (HCH), delta-hexachlorocyclohexane, heptachlor, aldrin and dieldrin. The other pesticides that were investigated are gamma-chlordane, alpha endosulfan, endosulfan sulfate, p,p'-DDT and its metabolite p,p'-DDE, methoxychlor, endrin and its metabolite endrin aldehyde and endrin ketone. The order of increasing frequency of detection of samples was higher in sediment than water. In sediment, the mean concentration ranged from 0.030 μg kg(-1) dry weight (endrin) to 10.98 μg kg(-1) dry weight (aldrin). The highest detected concentration of organochlorine in water was endosulfan sulfate with mean concentration of 0.185 μg L(-1). Analysis of variance indicated significant differences for most organochlorine pesticide residue in the sediment sampled from the various locations. Some of the levels of organochlorine pesticides detected in water were relatively high compared to guideline values set by World Health Organization and Australia and thus could be harmful if the trend is not checked.

  12. 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.

  13. [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.

  14. 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.

  15. Allergic reaction induced by dermal and/or respiratory exposure to low-dose phenoxyacetic acid, organophosphorus, and carbamate pesticides.

    PubMed

    Fukuyama, Tomoki; Tajima, Yukari; Ueda, Hideo; Hayashi, Koichi; Shutoh, Yasufumi; Harada, Takanori; Kosaka, Tadashi

    2009-07-10

    Several types of pesticides, such as organophosphates, phenoxyacetic acid, and carbamate have a high risk of affecting human health, causing allergic rhinitis and bronchial asthma-like diseases. We used our long-term sensitization method and a local lymph node assay to examine the allergic reactions caused by several types of pesticides. BALB/c mice were topically sensitized (9 times in 3 weeks), then challenged dermally or intratracheally with 2,4-D, BRP, or furathiocarb. One day post-challenge, the mice were processed to obtain biologic materials for use in assays of total IgE levels in serum and bronchoalveolar lavage fluid (BALF); differential cell counts and chemokine levels in BALF; lymphocyte counts and surface antigen expression on B-cells within regional lymph nodes (LNs); and, ex situ cytokine production by cells from these LNs. 2,4-D-induced immune responses characteristic of immediate-type respiratory reactions, as evidenced by increased total IgE levels in both serum and BALF; an influx of eosinophils, neutrophils, and chemokines (MCP-1, eotaxin, and MIP-1beta) in BALF; increased surface antigen expression on B-cells IgE and MHC class II production) in both auricular and the lung-associated LNs; and increased Th2 cytokine production (IL-4, IL-5, IL-10, and IL-13) in both auricular and the lung-associated LN cells. In contrast, BRP and furathiocarb treatment yielded, at most, non-significant increases in all respiratory allergic parameters. BRP and furathiocarb induced marked proliferation of MHC Class II-positive B-cells and Th1 cytokines (IL-2, TNF-alpha, and IFN-gamma) in only auricular LN cells. These results suggest that 2,4-D is a respiratory allergen and BRP and furathiocarb are contact allergens. As our protocol detected classified allergic responses to low-molecular-weight chemicals, it thus may be useful for detecting environmental chemical-related allergy.

  16. Optical instrument development for detection of pesticide residue in apple surface

    NASA Astrophysics Data System (ADS)

    Dhakal, Sagar; Li, Yongyu; Peng, Yankun; Chao, Kuanglin; Qin, Jianwei

    2013-05-01

    Apple is the world largest produced and consumed fruit item. At the same time, apple ranks number one among the fruit item contaminated with pesticide. This research focuses on development of laboratory based self-developed software and hardware for detection of commercially available organophosphorous pesticide (chlorpyrifos) in apple surface. A laser light source of 785nm was used to excite the sample, and Raman spectroscopy assembled with CCD camera was used for optical data acquisition. A hardware system was designed and fabricated to clamp and rotate apple sample of varying size maintaining constant working distance between optical probe and sample surface. Graphical Users Interface (GUI) based on LabView platform was developed to control the hardware system. The GUI was used to control the Raman system including CCD temperature, exposure time, track height and track centre, data acquisition, data processing and result prediction. Different concentrations of commercially available 48% chlorpyrifos pesticide solutions were prepared and gently placed in apple surface and dried. Raman spectral data at different points from same apple along the equatorial region were then acquired. The results show that prominent peaks at 341cm-1, 632cm-1 and 680 cm-1 represent the pesticide residue. The laboratory based experiment was able to detect pesticide solution of 20ppm within 3 seconds. A linear relation between Raman intensity and pesticide residue was developed with accuracy of 97.8%. The result of the research is promising and thus is a milestone for developing industrially desired real time, non-invasive pesticide residue detection technology in future.

  17. Decay of dinitroaniline herbicides and organophosphorus insecticides during brewing of lager beer.

    PubMed

    Navarro, Simón; Pérez, Gabriel; Navarro, Ginés; Mena, Luis; Vela, Nuria

    2006-07-01

    This article examines the fate of four pesticides that can be present during the brewing of lager beer. For this purpose, malted barley was spiked at 2 mg/kg with pendimethalin and trifluralin (dinitroaniline herbicides) and fenitrothion and malathion (organophosphorus insecticides). Analyses of pesticide residues were carried out by a gas chromatograph with an electron capture detector, and their identity was confirmed by gas chromatography-mass spectrometry. Cleanup was necessary for the malt and spent grain samples. Beginning with mashing and ending with the final product 4 months later, various samples (spent grain, sweet wort, brewer wort, and beer) were taken to determine the concentration of the targeted residual pesticides during the various beer making phases. In all cases, the residual levels recorded in sweet wort sampled after the mashing phase were below the respective maximum residue limits established by Spanish legislation for barley. Significant proportions of pesticide residues (17 to 40%) were retained on the spent grain. Applying the standard first-order kinetics equation (r > 0.91), the half-lives obtained for the four compounds during the storage of the spent grain (3.5 months) varied from 138 days (fenitrothion) to 192 days (malathion and pendimethalin). Herbicide residues practically disappeared (<0.3%) after wort boiling, whereas the percentages of the remaining insecticides, fenitrothion and malathion, ranged from 3.5 to 4.3%, respectively, at this time. No residues of dinitroaniline compounds were detected in young beer, whereas there was a significant reduction in fenitrothion (58%) and malathion (71%) residues during fermentation. Lagering and filtering processes also reduced the content of the organophosphorus insecticides (33 to 37%). Finally, after the storage period (3 months), the content of fenitrothion was reduced by 75%, with malathion residues being below its detection limit.

  18. 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.

  19. Organochlorine pesticide residues in woodcock, soils and earthworms in Louisiana, 1965

    USGS Publications Warehouse

    McLane, M.A.R.; Stickel, L.F.; Newsom, J.D.

    1971-01-01

    Woodcock (Philohela minor), earthworms, and soil samples were collected from January-March 1965, from fields in southeastern Louisiana approximately 3 years after discontinuance of areal treatments with heptachlor in this region. Heptachlor epoxide residues in woodcock averaged 0.42 ppm (dry weight), conspicuously lower than in 1961 and 1962. Residues of DDE in woodcock averaged 3.62 pprn, higher than in birds taken in the same area in 1961-62. Earthworms and soils contained traces of several organochlorine pesticides.

  20. 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...

  1. Distribution and migration of pesticide residues in mosquito control impoundments St. Lucie County, Florida, USA

    NASA Astrophysics Data System (ADS)

    Parkinson, R. W.; Wang, T. C.; White, J. R.; David, J. R.; Hoffman, M. E.

    1993-09-01

    This project was designed to: (1) document the distribution and migration of organochlorine pesticide residues within marsh substrates of 18 St. Lucie County mosquito control impoundments located along the Indian River Lagoon estuary, and (2) evaluate the impact of water management techniques on residue mobility. Our results indicate that detectible concentrations of organochlorine compounds, applied between the late 1940s and early 1950s, are present in 16 of the 18 St. Lucie County mosquito control impoundments. These compounds are primarily restricted to the surficial, organic-rich wetland sediment, which, based upon geotechnical analysis, was exposed to the atmosphere at a time when the impoundments were subjected to pesticide treatment. Contaminated sediments are present below the surficial, organic-rich layer, suggesting that some vertical migration of pesticides has occurred. It is unlikely that leaching associated with the downward percolation of impounded water was responsible for this migration as pesticide residues were never detected within the in situ pore waters. An alternative explanation is that biological processes (e.g., rooting, burrowing) facilitated the downward flux of organochlorine compounds into sediment horizons not subjected to direct treatment. Eighty-eight surface water samples obtained from two impoundments subjected to contrasting water management techniques were analyzed for pesticide content. None of the surficial water samples collected in association with these impoundments contained detectible concentrations of organochlorine compounds. These samples were unfiltered and contained as much as 25 mg/1 of particulate organic matter. This suggests that the currently preferred management technique (RIM), which is designed to maintain water quality, limit mosquito production, and provide for ecological continuity, does not hydraulically mobilize pesticide residues into the Indian River Lagoon estuary.

  2. 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%.

  3. Analysis of pesticide residues in hops and their extraction by liquid CO2 during the production of hop extracts.

    PubMed

    Williams, C S; Eastoe, B V; Slaiding, I R; Walker, M D

    1994-01-01

    A method has been developed for analysing pesticide residues in whole hops, hop pellets and hop extracts by GC-MS. Five batches of hop pellets containing nine different pesticides (triadimefon, dicofol, mephosfolan, bupirimate, cyhalothrin, tetradifon, endosulfan, pyrazophos and total bisdithiocarbamates) were extracted with liquid CO2. Pesticide concentrations in the original hop pellets and the extracts were determined. The pesticides were concentrated by the extraction process (concentration factor 1.3-8.3), except for the bisdithiocarbamates, which were not extracted. When the same amount of bitterness was added into the brewing process using liquid CO2 extract as opposed to hop pellets, for most of the pesticides proportionately less pesticide was added. However, for two pesticides (dicofol and triadimefon) corrected residue levels were similar to, or in some cases slightly higher than, those in hop pellets.

  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. Assessment of organochlorine pesticide residues in Indian flue-cured tobacco with gas chromatography-single quadrupole mass spectrometer.

    PubMed

    Ghosh, Rakesh Kumar; Khan, Zareen S; Rao, C V N; Banerjee, Kaushik; Reddy, D Damodar; Murthy, T G K; Johnson, Nalli; Ray, Deb Prasad

    2014-08-01

    Presence of pesticide residues in tobacco increases health risk of both active and passive smokers, apart from the imminent potential health problems associated with it. Thus, monitoring of pesticide residue is an important issue in terms of formulating stringent policies, enabling global trade and safeguarding the consumer's safety. In this study, a gas chromatography-single quadrupole mass spectrometry (GC-MS) method based upon quantifier-qualifier ions (m/z) ratio was employed for detecting and assessing ten organochlorine pesticide residues (α-HCH, β-HCH, γ-HCH, δ-HCH, 2,4-DDT, 4,4-DDT, endrin, α-endosulfan, β-endosulfan and endosulfan sulphate) in 152 flue-cured (FC) tobacco leave samples from two major tobacco growing states, Karnataka and Andhra Pradesh, of India. In the majority of samples, pesticide residue levels were below the limit of quantification (LOQ). In few samples, pesticide residues were detected and they found to comply with the guidance residue levels (GRL) specifications of the Cooperation Center for Scientific Research Relative to Tobacco (CORESTA). Detection of the phase out pesticides like DDT/HCH might be due to transfer of persistent residues from the environmental components to the plant. This is the first report on these ten organochlorine pesticide residues in Indian FC tobacco.

  6. 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).

  7. 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%).

  8. Stability of pesticides' residues under ultraviolet germicidal irradiation.

    PubMed

    Zabar, Romina; Sarakha, Mohamed; Chung, Pascal Wong Wah; Trebše, Polonca

    2011-06-01

    Legislation for food safety is limited mostly to pesticides monitoring and no attention is paid to the presence and toxicity of by-products formed after pesticide application. Stability studies of three selected transformation products: IMP - 2-isopropyl-6-methyl-4-pyrimidinol (diazinon hydrolysis product), TCP - 3,5,6-trichloro-2-pyridinol (chlorpyrifos transformation product), and 6CNA - 6-chloronicotinic acid (imidacloprid and acetamiprid transformation product) were performed under exposure to sunlight at room temperature (22 °C) and in the dark at 4 °C over 90 days. The results showed slight change in concentration with samples under refrigeration in darkness.Alternatively, an aqueous solution of TCP exposed to sunlight resulted in a high decrease of initial concentration within time. The toxicity assessment was performed using luminescent bacteria Vibrio fischeri and the results expressed low toxicity in the case of IMP and 6CNA. However, for TCP the calculated EC50 value after 30 minutes of exposure equated to roughly 15.1 mg L-1. Stability of the selected transformation products upon 245 nm irradiation indicated little decrease in concentration for IMP and 6CNA in deoxygenated and oxygenated aqueous solutions. In the case of TCP, the photochemical behaviour appeared to depend on oxygen concentration in the medium. For more detailed comparison, the degradation quantum yields were calculated.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Multi-residue determination of pesticides in vegetables by gas chromatography/ion trap mass spectrometry.

    PubMed

    Tao, C-J; Hu, J-Y; Li, J-Z; Zheng, S-S; Liu, W; Li, C-J

    2009-01-01

    To monitor possible contamination of edible vegetables by common pesticides, an analytical method using gas chromatography combined with ion trap spectrometry (GC-IT/MS) was developed to measure simultaneously up to 39 pesticide residues, belonging to organophosphors, organochlorines, pyrethroids or carbamates classes, left on four kinds of popular vegetables. The procedure entails addition of acetone, dichloromethane, and sodium chloride to a small amount of vegetable, then the mixture was shaken intensively and centrifuged for phase separation. An aliquot of the organic layer was cleanup using solid-phase extraction (SPE) cartridges filled with graphitized carbon black (GCB) in combination with acidic aluminum oxide. Gas chromatography with ion trap mass spectrometer was then used for qualitative and quantitative determination of the pesticides. The GCB combination with acidic aluminum oxide was found more suitable than florisil, aluminum oxide and silicon dioxide for sample cleanup with recoveries above 70% for most pesticides in removing the majority of co-extracted matrices. Variation coefficients of the repeatability typically smaller than 20% have been achieved for a wide range of the investigated pesticides. A set of critical instrument parameters for the GC-IT/MS Varian system in the MS mode was established. Based on optimization work conducted in this study, the 39 pesticides were separated successively with the limits of detection between 0.02 and 0.1 mg/kg.

  14. Solar photocatalytic activity of TiO2 modified with WO3 on the degradation of an organophosphorus pesticide.

    PubMed

    Ramos-Delgado, N A; Gracia-Pinilla, M A; Maya-Treviño, L; Hinojosa-Reyes, L; Guzman-Mar, J L; Hernández-Ramírez, A

    2013-12-15

    In this study, the solar photocatalytic activity (SPA) of WO3/TiO2 photocatalysts synthesized by the sol-gel method with two different percentages of WO3 (2 and 5%wt) was evaluated using malathion as a model contaminant. For comparative purpose bare TiO2 was also prepared by sol-gel process. The powders were characterized by X-ray diffraction (XRD), Raman spectroscopy, diffuse reflectance UV-vis spectroscopy (DRUV-vis), specific surface area by the BET method (SSABET), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy with a high annular angle dark field detector (STEM-HAADF). The XRD, Raman, HRTEM and STEM-HAADF analyses indicated that WO3 was present as a monoclinic crystalline phase with nanometric cluster sizes (1.1 ± 0.1 nm for 2% WO3/TiO2 and 1.35 ± 0.3 nm for 5% WO3/TiO2) and uniformly dispersed on the surface of TiO2. The particle size of the materials was 19.4 ± 3.3 nm and 25.6 ± 3 nm for 2% and 5% WO3/TiO2, respectively. The SPA was evaluated on the degradation of commercial malathion pesticide using natural solar light. The 2% WO3/TiO2 photocatalyst exhibited the best photocatalytic activity achieving 76% of total organic carbon (TOC) abatement after 300 min compared to the 5% WO3/TiO2 and bare TiO2 photocatalysts, which achieved 28 and 47% mineralization, respectively. Finally, experiments were performed to assess 2% WO3/TiO2 catalyst activity on repeated uses; after several successive cycles its photocatalytic activity was retained showing long-term stability.

  15. 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.

  16. 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.

  17. An isofenphos-methyl hydrolase (Imh) capable of hydrolyzing the P-O-Z moiety of organophosphorus pesticides containing an aryl or heterocyclic group.

    PubMed

    Li, Rong; Liu, Yuan; Zhang, Jian; Chen, Kai; Li, Shunpeng; Jiang, Jiandong

    2012-06-01

    Organophosphorus pesticide (OP) hydrolases play key roles in the degradation and decontamination of agricultural and household OPs and in the detoxification of chemical warfare agents. In this study, an isofenphos-methyl hydrolase gene (imh) was cloned from the isocarbophos-degrading strain of Arthrobacter sp. scl-2 using the polymerase chain reaction method. Isofenphos-methyl hydrolase (Imh) showed 98% sequence identity with the isofenphos hydrolase from Arthrobacter sp. strain B-5. Imh was highly expressed in Escherichia coli BL21 (DE3), and the His(6)-tagged Imh was purified (1.7 mg/ml) with a specific activity of 14.35 U/mg for the substrate isofenphos-methyl. The molecular mass of the denatured Imh is about 44 kDa, and the isoelectric point (pI) value was estimated to be 3.4. The optimal pH and temperature for hydrolysis of isofenphos-methyl were pH 8.0 and 35 °C, respectively. The secondary structure of Imh shows that Imh is a metallo-dependent hydrolase, and it was found that Imh was completely inhibited by the metalloprotease inhibitor 1,10-phenanthroline (0.5 mM), and the catalytic activity was restored by the subsequent addition of Zn(2+). Interestingly, Imh had a relatively broader substrate specificity and was capable of hydrolyzing 12 of the tested oxon and thion OPs with the P-O-Z moiety instead of the P-S(C)-Z moiety. Furthermore, it was found that the existence of an aryl or heterocyclic group in the leaving group (Z) is also important in determining the substrate specificity. Among all the substrates hydrolyzed by Imh, it was assumed that Imh preferred P-O-Z substrates still with a phosphamide bond (P-N), such as isofenphos-methyl, isofenphos, isocarbophos, and butamifos. The newly characterized Imh has a great potential for use in the decontamination and detoxification of agricultural and household OPs and is a good candidate for the study of the catalytic mechanism and substrate specificity of OP hydrolases.

  18. 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.

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

    PubMed

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

    2010-05-15

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

  20. 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

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

    Here we reported a residue-free green nanotechnology which synergistically enhance the pesticides efficiency and successively eliminate its residue. We built up a composite antifungal system by a simple pre-treating and assembling procedure for investigating synergy. Investigations showed 0.25 g/L ZnO nanoparticles (NPs) with 0.01 g/L thiram could inhibit the fungal growth in a synergistic mode. More importantly, the 0.25 g/L ZnO NPs completely degraded 0.01 g/L thiram under simulated sunlight irradiation within 6 hours. It was demonstrated that the formation of ZnO-thiram antifungal system, electrostatic adsorption of ZnO NPs to fungi cells and the cellular internalization of ZnO-thiram composites played important roles in synergy. Oxidative stress test indicated ZnO-induced oxidative damage was enhanced by thiram that finally result in synergistic antifungal effect. By reducing the pesticides usage, this nanotechnology could control the plant disease economically, more significantly, the following photocatalytic degradation of pesticide greatly benefit the human social by avoiding negative influence of pesticide residue on public health and environment.

  2. 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.

  3. Occurrence and estimation of pesticide residues in edible minor crops in southeastern Poland in 2013-2014.

    PubMed

    Podbielska, Magdalena; Szpyrka, Ewa; Matyaszek, Aneta; Słowik-Borowiec, Magdalena; Rupar, Julian; Kurdziel, Anna

    2016-07-01

    This paper presents the results of official control of pesticide residues in minor crops collected in southeastern Poland in 2013-2014. Compliance of used pesticides with applicable law was also verified, and determined residues were compared to maximum residue levels (MRLs) provided for in Regulation (EC) No. 395/2005. A total of 583 samples of 25 different types of fresh fruit and vegetables were analyzed for pesticide residues. Pesticide residues were detected in 158 samples (27.1 % of the analyzed samples). According to the European Commission Health & Consumer Protection Directorate-General (SANCO) guidelines document, MRL violations were understood as cases where a residue level exceeded the MRL after the uncertainty of the method (50 %) was considered. MRL violations were found in four samples. The usage of unauthorized pesticides was detected in 5.8 % of analyzed samples. Substances banned in Poland were found in two samples. Fungicides were the most frequently detected group of pesticides. Pesticide residues were most commonly found in fruit samples (19.4 % of all analyzed samples), mainly in gooseberry, redcurrant, and huckleberry. The majority of samples were compliant with MRLs, which means that they were suitable for trade.

  4. Effectiveness of cleaning practices in removing pesticides from home environments.

    PubMed

    McCauley, Linda A; Travers, Rachelle; Lasarev, Michael; Muniz, Juan; Nailon, Regina

    2006-01-01

    The deposition of agricultural pesticides in the homes of agricultural workers and residents of agricultural communities is a major environmental health concern. The effectiveness of home cleaning activities in removing pesticides from home surfaces has not been tested. An intervention study was conducted to assess the effectiveness of cleaning windowsills, floors and carpets in a sample of 10 farmworker homes. Baseline measures of organophosphorus (OP) pesticide residues were obtained, a standardized cleaning intervention was applied and follow-up measures of pesticide residues were obtained within 24-48 hours after the cleaning and 12 months later. House dust was analyzed for six OP pesticides. All homes had detectable baseline levels of OP pesticides on floors and windowsills. Cleaning of linoleum floors was ineffective in removing total pesticide residues and cleaning effectiveness varied among the pesticides. The cleaning of total OP pesticides on the windowsills was effective (median decrease was 0.0029 microg/cm(2), 1-sided p-value = 0.01). Steam cleaning carpets essentially reduced the amounts to non-detectable levels. In 12 months the levels in carpets had accumulated to one-third of the baseline levels. These results provide evidence that cleaning practices can reduce the amount of pesticides in agricultural homes; however the type of surface being cleaned and the pesticides present in the home may influence results.

  5. Unit-to-unit variability of pesticide residues in fruit and vegetables.

    PubMed

    Hill, Alan R C; Reynolds, Stewart L

    2002-08-01

    Pesticide residue levels (36 pesticides and some of their metabolites) were determined in the individual units taken from large samples of apples, bananas, celery, kiwi fruit, oranges, peaches and nectarines, pears, plums, potatoes, and tomatoes. The 65 large samples (generally about 100-110 units, but only 45 units of celery) were purchased at retail or wholesale outlets in the UK. The lots from which the samples were drawn originated from 17 different countries. Average concentrations in the samples were in the approximate range 0.002-2 mg kg(-1). Unit-to-unit variability factors (97.5th percentile mg kg(-1)/average mg kg(-1)), for the pesticide/product combination data sets in which >10% of samples contained measurable residues (n = 106), were in the range 1.4-9.6 (11.1 based on a value of zero for data below reporting limits). Analytical variance contributed only a small proportion (up to 11%) to the overall variance of the 106 data sets. There was no evidence of a relationship between the variability factor and the commodity, country of origin, residue concentration or the physicochemical characteristics of the pesticide. The extent of variability appears to be determined at or about the time of pesticide application. Taking non-detectable residues as half the reporting limits, the frequency distribution of variability factors was approximately log-normal, with a geometric mean of 3.4. The corresponding 95% probability limits of the variability factors were calculated to be 1.6 and 7.6.

  6. Relationship between the adsorption capacity of pesticides by wood residues and the properties of woods and pesticides.

    PubMed

    Rodriguez-Cruz, Sonia; Andrades, Maria S; Sanchez-Camazano, Maria; Sanchez-Martin, Maria J

    2007-05-15

    With the aim to explore the potential use of wood residues in technologies aimed at preventing the pollution of soil and water, we studied the adsorption of four non-ionic pesticides (linuron, alachlor, metalaxyl, and chlorpyrifos) and two ionic pesticides (dicamba and paraquat) with a Kow range of -4.5 to 4.7 by nine types of wood with lignin content in the 18.2-26.9% range. The Freundlich Kf values were considered as indicators of the adsorption capacity. A statistical study was carried out using simple and multiple correlations to establish the degree to which the different parameters of the woods and of the pesticides were involved in adsorption. In the case of the non-ionic pesticides, positive and negative significant correlations were observed between Kf and the lignin (r = 0.73-0.83, p < 0.05-0.01), and soluble C contents of the woods (r = 0.66-0.84), p < 0.1-0.01). For dicamba, a correlation between Kf and pH (r = -0.66, p < 0.1) of the woods was found, while for paraquat, this was seen between Kf and the cation exchange capacity (r = 0.71, p < 0.1) of the woods. No significant correlation was observed between Kf and the total C content of the woods. A highly significant correlation between Kf and Kow values (r > or = 0.93, p < 0.01) was found in the adsorption of the pesticides by the woods (with the exception of paraquat) showing that this parameter is very important in this adsorption process. The determination coefficient of the multiple correlation between Kf and the parameters Kow, soluble C, and lignin contents accounts for nearly 100% of the variability in adsorption for non-ionic pesticides. Based on the results of our study and of those of the literature related to the adsorption of aromatic hydrocarbons, we used the Kow values to define a predictive model of adsorption of hydrophobic organic compounds in general by the woods.

  7. Pesticides

    MedlinePlus

    ... and pets. Proper disposal of pesticides is also important - it can help protect the environment. Biologically-based pesticides are becoming more popular. They often are safer than traditional pesticides. Environmental Protection Agency

  8. Organochlorine pesticide residues in animals of Tasmania, Australia-1975-77.

    PubMed

    Bloom, H; Taylor, W; Bloom, W R; Ayling, G M

    1979-12-01

    Animals taken in Tasmania including duck (Anas superciliosa), eel (Anguilla australis), English perch (Perca fluviatilis), white-faced heron (Ardea pacifica), brown trout (Salmo trutta), European starling (Strunus vulgaris), cat (Felis cattus), cormorant (Phalacrocorax sp.), mutton bird (Puffinus tenuirostris), Tasmanian devil (Sarcophilus harrisii), rainbow trout (Salmo gairdnerii), Tasmanian raven (Corvus mellori), tench (Tinca tinca), and quail (Coturnix sp.) were sampled for p,p'-DDE, pp,p'-TDE, p,p'-DDT, lindane, dieldrin, and hexachlorobenzene. Pesticide residue levels exceeded 0.1 ppm in at least one animal from each area and in the majority of animals sampled from all areas. Pesticide sources could not be determined, partly because migratory species such as ducks, mutton birds, cormorants, and eels may have ingested pesticides outside of Tasmania.

  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. Pesticides residues and metals in plant products from agricultural area of Belgrade, Serbia.

    PubMed

    Ethorđević, Tijana; Ethurović, Rada

    2012-03-01

    The objective of study was to assess the levels of selected metals and pesticides in plant products from agricultural area of Belgrade, Serbia in order to indicate their possible sources and risks of contamination and to evaluate their sanitary probity and safety. The concentrations of cadmium, copper, iron, manganese, nickel, lead and zinc were below limits established by national and international regulations (maximum found concentrations were 0.028, 1.91, 11.16, 1.77, 0.605, 0.073 and 1.76 mg kg(-1) respectively). Only residue of one of examined pesticides was found in amount below MRL (bifenthrin 2.46 μg kg(-1)) in only one of analysed samples, while others were below detection limits. Obtained results indicate that crops from examined agricultural areas are unpolluted by contaminants used for plant protection and nutrition, indicating good agricultural practice regarding pesticides and fertilizer usage as well as moderate industrial production within examined areas.

  11. Pesticide residues in Portuguese strawberries grown in 2009-2010 using integrated pest management and organic farming.

    PubMed

    Fernandes, Virgínia C; Domingues, Valentina F; Mateus, Nuno; Delerue-Matos, Cristina

    2012-11-01

    Pesticides are among the most widely used chemicals in the world. Because of the widespread use of agricultural chemicals in food production, people are exposed to low levels of pesticide residues through their diets. Scientists do not yet have a total understanding of the health effects of these pesticide residues. This work aims to determine differences in terms of pesticide residue content in Portuguese strawberries grown using different agriculture practices. The Quick, Easy, Cheap, Effective, Rugged, and Safe sample preparation method was conducted and shown to have good performance for multiclass pesticides extraction in strawberries. The screening of 25 pesticides residue was performed by gas chromatography-tandem mass spectrometry. In quantitative validation, acceptable performances were achieved with recoveries of 70-120 and <12 % residual standard deviation for 25 pesticides. Good linearity was obtained for all the target compounds, with highly satisfactory repeatability. The limits of detection were in the range of 0.1-28 μg/kg. The method was applied to analyze strawberry samples from organic and integrated pest management (IPM) practices harvested in 2009-2010. The results showed the presence of fludioxonil, bifenthrin, mepanipyrim, tolylfluanid, cyprodinil, tetraconazole, and malathion when using IPM below the maximum residue levels.

  12. 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.

  13. Evaluation of two fast and easy methods for pesticide residue analysis in fatty food matrixes.

    PubMed

    Lehotay, Steven J; Mastovská, Katerina; Yun, Seon Jong

    2005-01-01

    Two rapid methods of sample preparation and analysis of fatty foods (e.g., milk, eggs, and avocado) were evaluated and compared for 32 pesticide residues representing a wide range of physicochemical properties. One method, dubbed the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for pesticide residue analysis, entailed extraction of 15 g sample with 15 mL acetonitrile (MeCN) containing 1% acetic acid followed by addition of 6 g anhydrous magnesium sulfate and 1.5 g sodium acetate. After centrifugation, 1 mL of the buffered MeCN extract underwent a cleanup step (in a technique known as dispersive solid-phase extraction) using 50 mg each of C18 and primary secondary amine sorbents plus 150 mg MgSO4. The second method incorporated a form of matrix solid-phase dispersion (MSPD), in which 0.5 g sample plus 2 g C18 and 2 g anhydrous sodium sulfate was mixed in a mortar and pestle and added above a 2 g Florisil column on a vacuum manifold. Then, 5 x 2 mL MeCN was used to elute the pesticide analytes from the sample into a collection tube, and the extract was concentrated to 0.5 mL by evaporation. Extracts in both methods were analyzed concurrently by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry. The recoveries of semi-polar and polar pesticides were typically 100% in both methods (except that basic pesticides, such as thiabendazole and imazalil, were not recovered in the MSPD method), but recovery of nonpolar pesticides decreased as fat content of the sample increased. This trend was more pronounced in the QuEChERS method, in which case the most lipophilic analyte tested, hexachlorobenzene, gave 27 +/- 1% recovery (n=6) in avocado (15% fat) with a<10 ng/g limit of quantitation.

  14. Organochlorine pesticide residues in bed sediments of the San Joaquin River and its tributary streams, California

    USGS Publications Warehouse

    Gilliom, R.J.; Clifton, D.G.

    1987-01-01

    The distribution and concentrations of organochlorine pesticide residues in bed sediments were assessed from samples collected at 24 sites in the San Joaquin River and its tributaries in the San Joaquin Valley, California. Sampling was designed to collect the finest grained bed sediments present in the vicinity of each site. One or more of the 14 pesticides analyzed were detected at every site. Pesticides detected at one or more sites were chlordane, DDD, DDE, DDT, dieldrin, endosulfan, mirex, and toxaphene. Pesticides not detected were endrin, heptachlor, heptachlor epoxide, lindane, methoxychlor, and perthane. The most frequently detected pesticides were DDD (83% of sites), DDE (all sites), DDT (33% of sites), and dieldrin (58% of sites). Maximum concentrations of these pesticides, which were correlated with each other and with the amount of organic carbon in the sample, were DDD, 260 micrograms/kg; DDE, 430 micrograms/kg; DDT, 420 micrograms/kg; and dieldrin, 8.9 micrograms/kg. Six small tributary streams that drain agricultural areas west of the San Joaquin River had the highest concentrations. Water concentrations and loads were estimated for each pesticide from its concentration in bed sediments, the concentration of suspended sediment, and streamflow. Estimated loadings of DDD, DDE, DDT, and dieldrin from tributaries to the San Joaquin River indicate that most of the loading to the river at the time of the study was probably from the westside tributaries. Estimated water concentrations exceeded the aquatic life criterion for the sum of DDD, DDE, and DDt of 0.001 microgram/L at nine of the 24 sites sampled. Five of the nine sites are westside tributaries and one is the San Joaquin River near Vernalis. (Author 's abstract)

  15. Residues of organochlorine pesticides in surface soil and raw foods from rural areas of the Republic of Tajikistan.

    PubMed

    Barron, Mace G; Ashurova, Zebunisso J; Kukaniev, Mukhamadcho A; Avloev, Hakbarqul K; Khaidarov, Karim K; Jamshedov, Jamshed N; Rahmatullova, Oygul S; Atolikshoeva, Sunbula S; Mamadshova, Sakina S; Manzenyuk, Oksana

    2017-05-01

    The central Asian Republic of Tajikistan has been an area of extensive historical agricultural pesticide use as well as large scale burials of banned chlorinated insecticides. The current investigation was a four year study of legacy organochlorine pesticides in surface soil and raw foods in four rural areas of Tajikistan. Study areas included the pesticide burial sites of Konibodom and Vakhsh, and family farms of Garm and Chimbuloq villages. These areas were selected to represent a diversity of pesticide disposal histories and to allow assessment of local pesticide contamination in Tajikistan. Each site was visited multiple times and over 500 samples of surface soil and raw foods were collected and analyzed for twenty legacy organochlorine pesticides. Various local food products were sampled to represent the range of raw foods potentially containing residues of banned pesticides, including dairy products, meat, edible plant and cotton seed products. The pesticide analytes included DDTs (DDT, DDD, DDE), lindane isomers (α, β, γ, δ BHC), endosulfan isomers (endosulfan I, II, sulfate), other cyclodienes (aldrin, α and γ chlordanes, dieldrin, endrin, endrin aldehyde and ketone, heptachlor, heptachlor epoxide), and methoxychlor. Pesticide analytes were selected based on availability of commercial standards and known or suspected historical pesticide use and burial. Pesticide contamination was highest in soil and generally low in meat, dairy, and plant products. DDT was consistently the highest measured individual pesticide at each of the four sampling areas, along with BHC isomers and endosulfan II. Soil concentrations of pesticides were extremely heterogeneous at the Vakhsh and Konibodam disposal sites with many soil samples greater than 10 ppm. In contrast, samples from farms in Chimbuloq and Garm had low concentrations of pesticides. Pesticide contamination in raw foods was generally low, indicating minimal transfer from the pesticide sites into local food

  16. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils.

    PubMed

    Centofanti, Tiziana; McConnell, Laura L; Chaney, Rufus L; Beyer, W Nelson; Andrade, Natasha A; Hapeman, Cathleen J; Torrents, Alba; Nguyen, Anh; Anderson, Marya O; Novak, Jeffrey M; Jackson, Dana

    2016-03-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18-39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.

  17. Organic amendments for risk mitigation of organochlorine pesticide residues in old orchard soils

    USGS Publications Warehouse

    Centofantia, Tiziana; McConnell, Laura L.; Chaney, Rufus L.; Beyer, W. Nelson; Andradea, Natasha A.; Hapeman, Cathleen J.; Torrents, Alba; Nguyen, Anh; Anderson, Marya O.; Novak, J. M.; Jackson, Dana

    2015-01-01

    Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day experiment. The use of aged dairy manure compost and biosolids compost was found to be effective, especially in the planted treatments, at lowering the bioavailability factor (BAF) by 18–39%; however, BAF results for DDT in the unplanted soil treatments were unaffected or increased. The pine chip biochar utilized in this experiment was ineffective at lower the BAF of pesticides in the soil. The US EPA Soil Screening Level approach was used with our measured values. Addition of 10% of the aged dairy manure compost reduced the average hazard quotient values to below 1.0 for DDT + DDE and dieldrin. Results indicate this sustainable approach is appropriate to minimize risks to wildlife in areas of marginal organochlorine pesticide contamination. Application of this remediation approach has potential for use internationally in areas where historical pesticide contamination of soils remains a threat to wildlife populations.

  18. Levels of organochlorine pesticides residues in human adipose tissue, data from Tabasco, Mexico.

    PubMed

    Waliszewski, Stefan M; Caba, M; Rodríguez Díaz, S S; Saldarriaga-Noreña, H; Meza, E; Zepeda, R; Infanzón, R

    2012-11-01

    The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, p,p'-DDE, o,p'-DDT and p,p'-DDT in 150 adipose tissue of inhabitants of Tabasco, Mexico. The following pesticides were detected: p,p'-DDE in 100% of samples at mean 1.034 mg/kg; p,p'-DDT in 96.7% at mean 0.116 mg/kg; o,p'-DDT in 78.7% at mean 0.022 mg/kg and β-HCH in 58.0% at mean 0.049 mg/kg. The pooled sample was divided according to sex of donors (75 female and 75 male). Significantly higher levels of all organochlorine pesticides in females were found. The sample was divided into three age's ranges (15-28, 29-45 and 46-84 years). The mean and median levels of β-HCH, p,p'-DDE and Σ-DDT increase significantly (p < 0.05) from the first to the second and third group. The presence of organochlorine pe