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Journal of Exposure Science &... Nov 2017Exposure of handlers'/operators' hands is a main route of agricultural pesticides entry into their body. Non-occupational handlers still lack information about... (Comparative Study)
Comparative Study
Exposure of handlers'/operators' hands is a main route of agricultural pesticides entry into their body. Non-occupational handlers still lack information about appropriate selection of protective gloves to minimize exposure and reduce adverse effects of these chemicals. According to the results of our previous survey, six commercially available, water-resistant gloves commonly used by non-professional gardeners were evaluated for permeation of Acetamiprid, Pirimicarb, and Chlorpyrifos-methyl (Chlorp-m) pesticides by means of in vitro testing. In-use conditions were mimicked as close as possible. Chlorp-m through latex was observed inside the glove from >10 to ⩽15 min; however, Acetamiprid and Pirimicarb through neoprene/latex and all the three pesticides through butyl were not observed inside gloves for the duration of the experiments (the Breakthrough time (BT)>8 h). The 1-h exposure proved the interior glove contamination with Chlorp-m through disposable latex, vinyl, and nitrile gloves (51, 33, and 41% of applied dose (AD), respectively) just as with Acetamiprid and Pirimicarb through latex glove (11 and 14%AD, respectively). However, when storing the used gloves for 4 days after the exposure, no release of the three pesticides from the butyl and Acetamiprid from neoprene/latex gloves was detected. In all other cases, pesticides were found in the interior glove (36-79, 31-63, and 51-81%AD for Acetamiprid, Pirimicarb, and Chlorp-m, respectively). If used repeatedly, gloves contaminated in this way lose their protective function but give the user a false sense of security. The results suggest that (i) water-resistant gloves are not necessarily pesticide resistant; (ii) disposable latex gloves commonly worn by non-professional gardeners provide inadequate protection even for a short-time contact with pesticides; (iii) to assess the efficiency of reusable gloves, not only BT value but also the reservoir/release effect of parent pesticide and its degradation products should be evaluated; and (iv) awareness-raising activities for non-occupational handlers of pesticides should be enhanced.
Topics: Agriculture; Environmental Exposure; Environmental Monitoring; Gloves, Protective; Humans; Latex; Neoprene; Permeability; Pesticides; Polyvinyl Chloride
PubMed: 27578185
DOI: 10.1038/jes.2016.47 -
Journal of Environmental Quality Jul 2016Pesticides stored at or close to the soil surface after field application can be mobilized and transported off the field when surface runoff occurs. The objective of our...
Pesticides stored at or close to the soil surface after field application can be mobilized and transported off the field when surface runoff occurs. The objective of our study was to quantify the potential pesticide losses in surface runoff from a conventionally managed agricultural field in a Swedish climate. This was achieved by measuring surface runoff volumes and concentrations in runoff of six spring-applied pesticides and autumn-applied glyphosate and its metabolite aminomethylphosphonic acid (AMPA). Measurements were performed for 3 yr both during the growing seasons and during intervening winter snowmelt periods on a clay loam field close to Uppsala. During growing seasons, surface runoff was generated on only five occasions during one 25-d period in 2012 when the infiltration capacity of the soil may have been reduced by structural degradation due to large cumulative rainfall amounts after harrowing. Concentrations in surface runoff exceeded Swedish water quality standards in all samples during this growing season for diflufenican and pirimicarb. Surface runoff was generated during three snowmelt periods during the winter of 2012-2013. All of the applied pesticides were found in snowmelt samples despite incorporation of residues by autumn plowing, degradation, and leaching into the soil profile during the period between spraying and sampling. Concentrations of glyphosate ranged from 0.12 to 7.4 μg L, and concentrations of AMPA ranged from 0 to 2.7 μg L. Our results indicate that temporal changes in hydraulic properties during the growing season and when the soil freezes during winter affect pesticide losses through surface runoff.
Topics: Aluminum Silicates; Clay; Pesticides; Soil; Sweden; Water Movements; Water Pollutants, Chemical
PubMed: 27380086
DOI: 10.2134/jeq2015.10.0528 -
Environmental Science & Technology Apr 2016Many chemicals in use end up in the aquatic environment. The toxicity of water samples can be tested with bioassays, but a metabolomic approach has the advantage that...
Many chemicals in use end up in the aquatic environment. The toxicity of water samples can be tested with bioassays, but a metabolomic approach has the advantage that multiple end points can be measured simultaneously and the affected metabolic pathways can be revealed. A current challenge in metabolomics is the study of mixture effects. This study aims at investigating the toxicity of an environmental extract and its most abundant chemicals identified by target chemical analysis of >100 organic micropollutants and effect-directed analysis (EDA) using the acetylcholinesterase (AChE) bioassay and metabolomics. Surface water from an agricultural area was sampled with a large volume solid phase extraction (LVSPE) device using three cartridges containing neutral, anionic, and cationic sorbents able to trap several pollutants classes like pharmaceuticals, pesticides, PAHs, PCBs, and perfluorinated surfactants. Targeted chemical analysis and AChE bioassay were performed on the cartridge extracts. The extract of the neutral sorbent cartridge contained most of the targeted chemicals, mainly imidacloprid, thiacloprid, and pirimicarb, and was the most potent AChE inhibitor. Using an EDA approach, other AChE inhibiting candidates were identified in the neutral extract, such as carbendazim and esprocarb. Additionally, a metabolomics experiment on the central nervous system (CNS) of the freshwater snail Lymnaea stagnalis was conducted. The snails were exposed to the extract, the three most abundant chemicals individually, and a mixture of these. The extract disturbed more metabolic pathways than the three most abundant chemicals individually, indicating the contribution of other chemicals. Most pathways perturbed by the extract exposure overlapped with those related to exposure to neonicotinoids, like the polyamine metabolism involved in CNS injuries. Metabolomics for the straightforward comparison between a complex mixture and single compound toxicity is still challenging but, compared to traditional biotesting, is a promising tool due to its increased sensitivity.
Topics: Acetylcholinesterase; Animals; Biological Assay; Cholinesterase Inhibitors; Enzyme Assays; Lymnaea; Metabolic Networks and Pathways; Metabolomics; Pesticides; Polyamines; Toxicity Tests; Water Pollutants, Chemical
PubMed: 26900769
DOI: 10.1021/acs.est.5b04577 -
Environmental Science and Pollution... May 2016Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the...
Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the adsorption of non-polar (tebuconazole, triadimenol) and polar (cymoxanil, pirimicarb) pesticides by soils after applying the biosorbent spent mushroom substrate (SMS) at different rates. The adsorption isotherms of pesticides by three soils and SMS-amended soils were obtained and the adsorption constants were calculated. The distribution coefficients (K d) increased 1.40-23.1 times (tebuconazole), 1.08-23.7 times (triadimenol), 1.31-42.1 times (cymoxanil), and 0.55-23.8 times (pirimicarb) for soils amended with biosorbent at rates between 2 and 75 %. Increasing the SMS rates led to a constant increase in adsorption efficiency for non-polar pesticides but not for polar pesticides, due to the increase in the organic carbon (OC) content of soils as indicated by K OC values. The OC content of SMS-amended soils accounted for more than 90 % of the adsorption variability of non-polar pesticides, but it accounted for only 56.3 % for polar pesticides. The estimated adsorption of SMS-amended soils determined from the individual adsorption of soils and SMS was more consistent with real experimental values for non-polar pesticides than for polar pesticides. The results revealed the use of SMS as a tool to optimize pesticide adsorption by soils in dealing with specific contamination problems involving these compounds.
Topics: Adsorption; Agaricales; Agriculture; Pesticides; Soil; Soil Pollutants; Triazoles; Water Pollution
PubMed: 26832876
DOI: 10.1007/s11356-016-6132-4 -
Journal of Economic Entomology Apr 2016The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is an important cosmopolitan and extremely polyphagous species capable of causing direct and indirect...
The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is an important cosmopolitan and extremely polyphagous species capable of causing direct and indirect damage to various crops. Insecticide resistance in melon aphids is of particular concern. To determine the basis of resistance, organophosphate (OP)-resistant strains of A. gossypii were obtained by continuous selection with dimethoate in the laboratory, and resistance mechanisms were investigated along with susceptible strains. Three resistant strains LKR-1, LKR-2, and LKR-3 exhibiting 270-, 243-, and 210-fold resistance obtained after 30 generations of selection with dimethoate, respectively, were utilized in this study. The role of acetylcholinesterase (AChE), a target enzyme for OPs and carbamates (CMs), was investigated. AChE enzyme assay revealed that there was no significant change in the activities of AChE in resistant and susceptible strains. However, AChE inhibitory assay showed that 50% of the enzyme activity in resistant strains was inhibited at significantly higher concentration of dimethoate (131.87, 158.65, and 99.29 µmolL(−1)) as compared with susceptible strains (1.75 and 2.01 µmolL(−1)), indicating AChE insensitivity owing to altered AChE. Molecular diagnostic tool polymerase chain reaction-restriction fragment length polymorphism revealed the existence of two consistent non-synonymous point mutations, single-nucleotide polymorphism, viz., A302S (equivalent to A201 in Torpedo californica Ayres) and S431F (equivalent to F331 in T. californica), in the AChE gene Ace2 of resistant strains. Further, cloning and sequencing of a partial fragment of Ace2 (897 bp) gene from susceptible and resistant strains revealed an additional novel mutation G221A in resistant strains, LKR-1 and LKR-2. Susceptible Ace2 genes shared 99.6 and 98.9% identity at the nucleic acid and amino acid levels with resistant ones, respectively. Functional analysis of these point mutations was assessed by in silico docking studies using the modeled wild-type and naturally mutated AChE2. Computational analysis showed that the conformational changes in AChE2 active site due to structural gene substitutions (A302S, S431F, and G221A) significantly reduced the level of ligand (OP-dimethoate, omethoate, and CM-pirimicarb) binding, suggesting that they are potentially associated with resistance development. These results unambiguously suggested that multiple mutations located in the enzyme active site are responsible for AChE insensitivity to dimethoate and are likely the molecular basis for dimethoate resistance in these selected field populations of A. gossypii.
Topics: Acetylcholinesterase; Animals; Aphids; Dimethoate; Insecticide Resistance; Insecticides; Molecular Docking Simulation; Point Mutation; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Sequence Analysis, DNA; Sequence Homology, Amino Acid
PubMed: 26797869
DOI: 10.1093/jee/tov403 -
Bulletin of Environmental Contamination... Apr 2016Surface water sampling in 2007-2010 measured the occurrence of carbamates and metalaxyl during base flow conditions and wet weather events in southern Ontario surface...
Surface water sampling in 2007-2010 measured the occurrence of carbamates and metalaxyl during base flow conditions and wet weather events in southern Ontario surface waters. Carbaryl, metalaxyl and pirimicarb were the most frequently detected compounds. In 2008 these three compounds were detected in over 50 % of the samples. Overall mean concentrations of carbaryl and metalaxyl over the course of the study (2007-2010) were 15 and 18 ng/L, respectively. Elevated concentrations of carbaryl (~100 to ~950 ng/L) appeared associated with wet weather (high flow) events, while highest concentrations of metalaxyl (~20-1330 ng/L) were correlated with base flow conditions. We attributed these observations as the result of runoff of carbaryl from the watershed during rain events, while metalaxyl contamination may have resulted primarily from spray drift.
Topics: Alanine; Carbamates; Carbaryl; Environmental Monitoring; Fresh Water; Ontario; Pesticides; Pyrimidines; Rain; Water Pollutants, Chemical
PubMed: 26754544
DOI: 10.1007/s00128-015-1719-x -
Analytical and Bioanalytical Chemistry Dec 2015As the consumption of aquatic products increased, the need for regulation of pesticide residues in aquatic products also emerged. Thus, in this study, a scheduled...
As the consumption of aquatic products increased, the need for regulation of pesticide residues in aquatic products also emerged. Thus, in this study, a scheduled multiple reaction monitoring (sMRM) method employing a novel extraction and purification step based on QuEChERS with EDTA was developed for the simultaneous quantitation of 20 pesticides (alachlor, aldicarb, carbofuran, diazinon, dimethoate, dimethomorph, ethoprophos, ferimzone, fluridone, hexaconazole, iprobenfos, malathion, methidathion, methiocarb, phenthoate, phosalone, phosmet, phosphamidon, pirimicarb, and simazine) in aquatic products. Additionally, the present method was validated in the aspects of specificity, linearity (r ≥ 0.980), sensitivity (the limit of quantitation (LOQ) ≤ 5 ng/g), relative standard deviation, RSD (1.0% ≤ RSD ≤ 19.4%), and recovery (60.1% ≤ recovery ≤ 117.9%). Finally, the validated method was applied for the determination of the 20 pesticide residues in eel and shrimp purchased from local food markets. In the present study, QuEChERS with EDTA was successfully expanded to residual pesticide analysis for the first time. The present method could contribute to the rapid and successful establishment of the positive list system in South Korea.
Topics: Animals; Eels; Food Contamination; Fruit; Mass Spectrometry; Palaemonidae; Pesticide Residues; Seafood; Solid Phase Extraction; Vegetables; Water Pollutants, Chemical
PubMed: 26466578
DOI: 10.1007/s00216-015-9071-x -
EXCLI Journal 2015A dramatic increase in pesticide usage in agriculture highlights the need for on-site monitoring for public health and safety. Here, a paper-based sensor combined with a...
A dramatic increase in pesticide usage in agriculture highlights the need for on-site monitoring for public health and safety. Here, a paper-based sensor combined with a wet system was developed for the simple and rapid screening of organophosphate (OP) and carbamate (CM) pesticides based on the inhibition of acetylcholinesterase (AChE). The paper-based sensor was designed as a foldable device consisting of a cover and detection sheets pre-prepared with indoxyl acetate and AChE, respectively. The paper-based sensor requires only the incubation of a sample on the test zone for 10 minutes, followed by closing of the foldable sheet to initiate the enzymatic reaction. Importantly, the buffer loading hole was additionally designed on the cover sheet to facilitate the interaction of the coated substrate and the immobilized enzyme. This subsequently facilitates the mixing of indoxyl acetate with AChE, resulting in the improved analytical performance of the sensor. The absence or decrease in blue color produced by the AChE hydrolysis of indoxyl acetate can be observed in the presence of OPs and CMs. Under optimized conditions and using image analysis, the limit of detection (LOD) of carbofuran, dichlorvos, carbaryl, paraoxon, and pirimicarb are 0.003, 0.3, 0.5, 0.6, and 0.6 ppm, respectively. The assay could be applied to determine OP and CM residues in spiked food samples. Visual interpretation of the color signal was clearly observed at the concentration of 5 mg/kg. Furthermore, a self-contained sample pre-concentration approach greatly enhanced the detection sensitivity. The paper-based device developed here is low-cost, requires minimal reagents and is easy to handle. As such, it would be practically useful for pesticide screening by non-professional end-users.
PubMed: 26417364
DOI: 10.17179/excli2014-684 -
Roczniki Panstwowego Zakladu Higieny 2015Peaches, sour cherries, nectarines, apricots, plums and cherries are fruit commonly known as "stone fruit". Their nutritional properties namely, vitamins, minerals,...
BACKGROUND
Peaches, sour cherries, nectarines, apricots, plums and cherries are fruit commonly known as "stone fruit". Their nutritional properties namely, vitamins, minerals, fiber and numerous microelements, make them a very important component of human diet. As fruit trees can be attacked by numerous diseases and pests, chemical protection of these crops is used. Therefore, it is important that the relevant governmental agencies or institutions ensure correct application of pesticides.
OBJECTIVE
The aim of the study was to evaluate the occurrence of pesticide residues in stone fruits south-eastern region of Poland in 2012-2014 in order to provide data to estimate health risk to consumers.
MATERIAL AND METHODS
Validated analytical methods based on liquid / liquid extraction coupled with gas chromatography with electron capture and nitrogen phosphorus detection (GC-ECD/NPD) and spectrophotometry (dithiocarbamates residues) were used for the analysis. 92 samples of stone fruits were tested for the presence of pesticide residues.
RESULTS
13 of all samples (14%) contained pesticide residues. 7 active substances were detected, including 5 fungicides: boscalide, bupirimate, difenoconazole, dithiocarbamates and captan, and 2 insecticides: cypermethrin and pirimicarb. In the analysed samples, the use of not recommended plant protection products in orchard crops were found. However, neither maximum residue levels (MRLs) recommended by the Regulation (EC) No 396/2005 were exceeded nor pesticides being unapproved by the Regulation (EC) No 1107/2009 detected in the analysed samples.
CONCLUSIONS
Lack of plant protection products for control specific diseases or pests in crops results in the use of formulations not recommended for use in certain orchard crops. On a basis of results reported in previous years it can be concluded that occurrence of pesticide residues in stone fruit samples dropped significantly.
Topics: Bridged Bicyclo Compounds; Dioxolanes; Endosulfan; Food Contamination; Fruit; Humans; Insecticides; Maximum Allowable Concentration; Pesticide Residues; Pesticides; Poland; Pyrimidines; Thiocarbamates; Triazoles
PubMed: 26400116
DOI: No ID Found -
Environmental Science and Pollution... Nov 2015Tomato (Lycopersicon esculentum Mill.) becomes one of the world's foremost vegetables, and its world production and consumption have increased fairly quickly. The...
Tomato (Lycopersicon esculentum Mill.) becomes one of the world's foremost vegetables, and its world production and consumption have increased fairly quickly. The capacity to induce oxidative stress in tomato plant, exposed to three xenobiotics such as alpha-cypermethrin, chlorpyriphos, and pirimicarb, was investigated by the evaluation of lipid peroxidation by measuring malondialdehyde (MDA) rate; also, we studied the response of tomato to this stress by assessing the response of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), glutathione-s-transferase (GST), and glutathione reductase (GR). The effect of the insecticides was observed using four concentrations (25, 50, 75, and 100%) for germinating seeds and only the recommended concentration in agriculture (100%) for growing plants. Our results show an important accumulation of MDA, demonstrating the increase of lipid peroxidation in consequence of the excessive reactive oxygen species (ROS) production due to insecticide treatment. In response to this oxidative stress in tomato seedlings and plants, the activities of antioxidant-enzyme system were generally enhanced. The electrophoretic analysis showed also the apparition of new isoenzymes as the case for CAT and POD.
Topics: Carbamates; Insecticides; Lipid Peroxidation; Solanum lycopersicum; Malondialdehyde; Oxidative Stress; Oxidoreductases; Pyrethrins; Pyrimidines
PubMed: 26178835
DOI: 10.1007/s11356-015-5024-3