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Food Additives & Contaminants. Part B,... Dec 2019The detection of pesticide residues in leafy vegetables has been a relevant concern in Chile over the last years. There is also a priority at the national level to...
The detection of pesticide residues in leafy vegetables has been a relevant concern in Chile over the last years. There is also a priority at the national level to propose a methodology to assess health risks. The aim of this study was to evaluate the presence of pesticide residues in ready-to-eat leafy vegetables in order to evaluate different models for health risk assessment. The models considered data of the World Health Organization (WHO) and the Ministry of Health of Chile (MINSAL). The Hazard Quotients and Hazard Indexes for the pesticides evaluated in all models decreased in the following order: methamidophos>lambda-cyhalothrin> chlorpyrifos. From a food safety perspective, the investigated samples suggest the presence of a greater health risk to consumers when compared using the official data of MINSAL, which needs appropriate attention.
Topics: Chile; Dietary Exposure; Humans; Pesticide Residues; Risk Assessment; Vegetables
PubMed: 31177966
DOI: 10.1080/19393210.2019.1625975 -
Environmental Science and Pollution... Jul 2019Farmland soil sprayed with organophosphorus pesticides (OPs) annually was investigated for the identification and characterization of OP-degrading microorganisms. Six...
Farmland soil sprayed with organophosphorus pesticides (OPs) annually was investigated for the identification and characterization of OP-degrading microorganisms. Six bacterial strains were identified, including Brevundimonas faecalis MA-B12 and Alcaligenes faecalis subsp. parafaecalis MA-B13 for methamidophos degradation, Citrobacter freundii TF-B21 and Ochrobactrum intermedium TF-B23 for trichlorfon degradation, Ochrobactrum intermedium DV-B31 for dichlorvos degradation, and Bacillus cereus for dimethoate degradation. The optimal biodegradation conditions for OPs were obtained at pH 7.0 and incubation temperature ranging from 28 to 37 °C. In an 8-day batch test, biodegradation of the four OPs all followed first-order kinetics, with biodegradation rates ranging from 58.08 to 96.42%. Functional genes responsible for OPs degradation were obtained, including ophB, ampA, opdE, opd, opdA, and mpd. As these strains were indigenous strains isolated from farmland soils, they can be potentially used as bacterial consortium for the bioremediation of mixed OP-contaminated soils. A time-course genotoxicity assessment of the degradation products was done by a bacterial whole-cell bioreporter, revealing that biodegradation of trichlorfon, dichlorvos, and dimethoate resulted a decreased genotoxicity within 5 days, which, however, significantly increased on day 8. The result demonstrated that more toxic products may be produced during the biodegradation processes of OPs, and more attention should be put not only on the pesticides themselves, but also on the toxic effects of their degradation products. To the best of our knowledge, this is for the first time that the genotoxicity of OP degradation products was evaluated by the bioreporter assay, broadening our understanding on the genotoxic risks of OPs during biodegradation process. Graphical Abstract.
Topics: Bacillus cereus; Biodegradation, Environmental; DNA Damage; Dichlorvos; Dimethoate; Kinetics; Organophosphorus Compounds; Pesticides; Soil
PubMed: 31129897
DOI: 10.1007/s11356-019-05135-9 -
Forensic Science International Jul 2019We herein report an intoxication case caused by the ingestion of the pesticide Ortoran, which consists of 50% acephate aqueous solution. A man in his 60 s was found...
We herein report an intoxication case caused by the ingestion of the pesticide Ortoran, which consists of 50% acephate aqueous solution. A man in his 60 s was found dead in his car with a 100-mL bottle containing approximately 50 mL of Ortoran. In a gas chromatography - mass spectrometry (GC-MS) screening test, acephate and its metabolite methamidophos were qualitatively detected in his stomach contents. The amounts of acephate and methamidophos (μg/g) in the extract of each body fluid or organ tissue were measured using GC-MS and were as follows: 35.8, 2.84 (heart blood); 44.0, 2.26 (peripheral blood); 2,240, 2.79 (urine); 53.1, 8.91 (brain occipital lobe); 43.7, 2.95 (liver); 102.3, 8.02 (right kidney); and 5450, 22.9 (stomach contents). Based on these results and autopsy findings, the cause of death was concluded to be acute fatal intoxication caused by the pesticide containing acephate and its active metabolite, methamidophos. Concentration ratios between acephate and methamidophos in each body fluid and organ tissue showed higher relative concentrations of brain methamidophos to acephate than those of other organ tissues. A high relative concentration of brain methamidophos may contribute to the intoxication of acephate in humans.
Topics: Brain Chemistry; Gas Chromatography-Mass Spectrometry; Gastrointestinal Contents; Humans; Insecticides; Kidney; Liver; Lung; Male; Middle Aged; Organothiophosphorus Compounds; Phosphoramides; Tissue Distribution
PubMed: 31000354
DOI: 10.1016/j.forsciint.2019.02.015 -
Industrial Health Feb 2020This study explored the potential association between chronic exposure to pesticide mixtures including paraquat and respiratory outcomes among Colombian farmers....
This study explored the potential association between chronic exposure to pesticide mixtures including paraquat and respiratory outcomes among Colombian farmers. Sociodemographic and occupational data, respiratory symptoms and spirometric data were collected. Paraquat in spot urine samples were quantified with solid-phase extraction high-performance liquid chromatography. Multiple Poisson regressions with robust variance were used to determine factors associated with respiratory outcomes. Profiles of pesticide mixtures used were identified among 217 farmworkers, but profenofos and methamidophos-based mixtures were more frequent. Chronic paraquat exposure was slightly associated with self-reported asthma (PR: 1.06; 95% CI 1.00 to 1.13). Different pesticide mixtures were associated with flu, thoracic pain, allergic rhinitis, and obstructive pattern in spirometry. Although acute exposure to paraquat is low among Colombian farmers participating in the study, associations between respiratory outcomes and chronic pesticide mixtures exposure including profenofos, methamidophos or glyphosate require further specific studies.
Topics: Adolescent; Adult; Aged; Chest Pain; Colombia; Farmers; Female; Humans; Male; Middle Aged; Occupational Exposure; Organothiophosphates; Organothiophosphorus Compounds; Paraquat; Pesticides; Respiratory Tract Diseases; Rhinitis, Allergic; Spirometry
PubMed: 30996154
DOI: 10.2486/indhealth.2018-0111 -
Journal of Hazardous Materials Jul 2019Transition metal oxides (TMOs) derived from metal - organic frameworks (MOF) combined with two-dimensional (2D) transition metal carbides possibly pave an innovative...
Transition metal oxides (TMOs) derived from metal - organic frameworks (MOF) combined with two-dimensional (2D) transition metal carbides possibly pave an innovative pathway for designing promising biosensors. Herein, a novel electrochemical sensing platform has been fabricated for ultra-sensitive determination of organophosphorus pesticides (OPs), based on MOF-derived MnO/MnO and TiC MXene/Au NPs composites. Remarkably, the three-dimensional (3D) MnO/MnO hierarchical microcuboids derived from Mn-MOF are composed of vertically aligned, highly ordered nanosheets, and further combined with MXene/Au NPs yields synergistic signal amplification effect, with outstanding electrochemical performance, large specific surface area, and good environmental biocompatibility. Under the optimum conditions, the reported sensing platform AChE-Chit/MXene/Au NPs/MnO/MnO/GCE can be utilized to detect methamidophos in a broad concentration range (10-10 M), together with a good linearity (R = 0.995). Besides that, the biosensor possesses a low limit of detection (1.34 × 10 M), which far exceeds the maximum residue limits (MRLs) for methamidophos (0.01 mg/kg) established by European Union. Additionally, the feasibility of the proposed biosensor for detecting methamidophos in real samples has been demonstrated with excellent recoveries (95.2%-101.3%). Interestingly, the unique structures and remarkable properties of these composites make them attractive materials for various electrochemical sensors for monitoring either pesticide residuals or other environmentally deleterious chemicals.
Topics: Electrochemical Techniques; Gold; Manganese Compounds; Nanostructures; Organothiophosphorus Compounds; Oxides; Pesticides; Titanium
PubMed: 30933859
DOI: 10.1016/j.jhazmat.2019.03.083 -
Journal of Exposure Science &... Jul 2020The use of pesticides has increased during the past decades, also increasing the risk of exposure to toxic pesticides that can cause detrimental health effects in the...
The use of pesticides has increased during the past decades, also increasing the risk of exposure to toxic pesticides that can cause detrimental health effects in the future. This is of special concern among farmers in low-to-middle-income countries that may lack proper training in the safe use of these chemicals. To assess the situation in Bolivia a cross-sectional study in three agricultural communities was performed (n = 297). Handling, use of personal protective equipment (PPE) and pesticide exposure were assessed by a questionnaire and measurements of urinary pesticide metabolites (UPMs). Results showed that methamidophos (65%) and paraquat (52%) were the most commonly used pesticides and that 75% of the farmers combined several pesticides while spraying. Notably, only 17% of the farmers used recommended PPEs while 84% reported to have experienced symptoms of acute pesticide poisoning after spraying. UPM measurements indicated high levels of exposure to chlorpyrifos, pyrethroids and 2,4D and that men generally were more highly exposed compared to women. Our study demonstrates that farmers who are better at following recommendations for pesticide handling and use of PPE had a significantly lower risk of having high UPM levels of most measured pesticides. Our results thus confirm the need of proper training of farmers in low-to-middle-income countries in proper protection and pesticide handling in order to reduce exposure levels and health problems.
Topics: Adult; Agriculture; Biomarkers; Bolivia; Cross-Sectional Studies; Farmers; Female; Health Knowledge, Attitudes, Practice; Hispanic or Latino; Humans; Male; Occupational Exposure; Pesticides; Surveys and Questionnaires
PubMed: 30787424
DOI: 10.1038/s41370-019-0128-3 -
Environmental Entomology Apr 2019Worldwide studies have used the technique of pollen trapping, collecting pollen loads from returning honey bee (Apis mellifera L.) (Hymenoptera: Apidae) foragers, to...
Worldwide studies have used the technique of pollen trapping, collecting pollen loads from returning honey bee (Apis mellifera L.) (Hymenoptera: Apidae) foragers, to evaluate the exposure of honey bees to pesticides through pollen and as a biomonitoring tool. Typically, these surveys have found frequent contamination of pollen with multiple pesticides, with most of the estimated risk of acute oral toxicity to honey bees coming from insecticides. In our survey of pesticides in trapped pollen from three commercial ornamental plant nurseries in Connecticut, we found most samples within the range of acute toxicity in a previous state pollen survey, but a few samples at one nursery with unusually high acute oral toxicity. Using visual sorting by color of the pollen pellets collected in two samples from this nursery, followed by pesticide analysis of the sorted pollen and palynology to identify the plant sources of the pollen with the greatest acute toxicity of pesticide residues, we were able to associate pollen from the plant genus Spiraea L. (Rosales: Rosaceae) with extraordinarily high concentrations of thiamethoxam and clothianidin, and also with high concentrations of acephate and its metabolite methamidophos. This study is the first to trace highly toxic pollen collected by honey bees to a single plant genus. This method of tracking high toxicity pollen samples back to potential source plants could identify additional high-risk combinations of pesticide application methods and timing, movement into pollen, and attractiveness to bees that would be difficult to identify through modeling each of the contributing factors.
Topics: Animals; Bees; Gardening; Guanidines; Insecticides; Neonicotinoids; Pesticide Residues; Pollen; Spiraea; Thiamethoxam; Thiazoles
PubMed: 30753426
DOI: 10.1093/ee/nvz007 -
Journal of Insect Science (Online) Nov 2018Propylaea japonica (Thunberg) was a dominant species among the predacious ladybirds in the fields and active from March to November during a year in Fuzhou, China....
Propylaea japonica (Thunberg) was a dominant species among the predacious ladybirds in the fields and active from March to November during a year in Fuzhou, China. Stability of insecticide resistance and vitality in adult P. japonica were investigated. The field ladybird P. japonica in Fuzhou, China, showed 9- to 16-fold resistance ratios to chlorpyrifos, 13- to 2,083-fold to methamidophos, 32- to 230-fold to fenvalerate, and 4- to 49-fold to avermectins, respectively, based on the field monitoring during 2004, 2009, and 2012, as compared with insecticide-susceptible F39 progenies. The resistance levels in the field P. japonica were high during May and November but low during summer. The population growth tendency index in field P. japonica was 0.8-fold as high as that in insecticide-susceptible P. japonica. The field P. japonica also showed high tolerance to the insecticide as compared with pest Lipaphis erysimi Kaltenbach and two parasitoids Diaeretiella rapae and Pachyneuron aphidis. Stable insecticide resistance levels and high vitality were found first in adult P. japonica with 1-, 30-, or 60-d-old adults, or among the adults developed form the eggs produced by newly emerged adults or by 60-d-old adults. Increased activity of glutathione S-transferases, carboxylesterases, and cytochrome P450 monooxygenases might be involved in the resistance of P. japonica. The results indicated that, in certain areas, inclusion of P. japonica for pest control in the integrated pest management would be highly recommended.
Topics: Animals; China; Coleoptera; Insecticide Resistance; Insecticides; Seasons
PubMed: 30535415
DOI: 10.1093/jisesa/iey109 -
Food Chemistry Feb 2019An efficient method for the rapid extraction and clean-up of 20 pesticide residues from polyphenol-rich agricultural samples (tea, apple, broccoli, and shallot) for...
An efficient method for the rapid extraction and clean-up of 20 pesticide residues from polyphenol-rich agricultural samples (tea, apple, broccoli, and shallot) for analysis by UPLC-MS/MS was developed. Following extraction, PVPP was used to precipitate polyphenols, supernatant was diluted to minimize matrix effects. Homogenized samples were vortexed in acetonitrile prior to cleanup with a combination of PVPP (150 mg), PSA (50 mg) and GCB (10 mg). Supernatant (1 mL) was filtered and diluted 10-fold before analysis. In 4 agricultural products that usually produce high interference, the matrix effects were overcome for all pesticides expect in green and oolong tea for acephate, omethoate, dinotefuran and nitenpyram. Mean recoveries ranged from 73% to 106%, and RSD ≦ 13%. Limits of quantification ranged from 0.01 to 0.02 mg kg. PVPP as one of excellent QuEChERS material combined with dilution was verified as a promising method for multiple pesticide residues analysis in complex matrices.
Topics: Agriculture; Chemical Fractionation; Chromatography, High Pressure Liquid; Costs and Cost Analysis; Food Contamination; Pesticide Residues; Polyphenols; Safety; Tandem Mass Spectrometry; Time Factors
PubMed: 30372964
DOI: 10.1016/j.foodchem.2018.08.134 -
Journal of Economic Entomology Feb 2019A piezoelectric quartz crystal impedance (PQCI) sensor was used to investigate influences of the insecticide methamidophos on proteinase activity in midguts of the wolf...
A piezoelectric quartz crystal impedance (PQCI) sensor was used to investigate influences of the insecticide methamidophos on proteinase activity in midguts of the wolf spider, Pardosa pseudoamulata (Araneae: Lycosidae). Results from PQCI indicated that low-concentration dose methamidophos (0.008%) can activate the proteinase but high-concentration dose methamidophos (0.016-0.032%) can inhibit the enzyme activity. The changes in subcellular structure of spider midgut cells were also observed. Electron micrographs of spider midgut epithelial cells showed that the low-dose methamidophos did not visibly impact the structure of these cells. Conversely, high-concentration dose methamidophos led to severe changes in the cell structure, including the karyotheca dissolved, the nucleolus, and the endoplasmic reticulum disappeared. These may contribute to changes in proteinase activity of spider. This work documents a feasible method for rapid and reliable detection of proteinase activity.
Topics: Animals; Female; Gastrointestinal Tract; Hydrolysis; Insect Proteins; Insecticides; Organothiophosphorus Compounds; Peptide Hydrolases; Spiders
PubMed: 30321348
DOI: 10.1093/jee/toy318