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Salud Publica de Mexico Jun 2021Objective. Evaluate compliance with the maximum permissible limits for pesticide residues in food in the state of Veracruz, as well as the risk to human health due to...
Objective. Evaluate compliance with the maximum permissible limits for pesticide residues in food in the state of Veracruz, as well as the risk to human health due to its consumption. Materials and methods. The concentration of pesticide residues in plant products were measured for comparison with the values established as safety limits and the regulatory framework for the use of pesticides. The hazard quotient and its possible effect on health were calculated. Results. 14.8% of the samples exceeded the allowed concentration. We found banned pesticides (methamidophos, monochotophos, triazophos and chlorpyrifos) that exceeded the established references dose, which increase the risk of possible neurological, hepatotoxic and endocrine alterations in health. Conclusions. There is the presence of highly hazardous pesticides, which are prohibited by international environmental conventions due to their impact on health and the environment, which is why their elimination is necessary. The regulatory framework in Mexico must be updated and dynamic as the knowledge of the adverse health effects of pesticides advances.
Topics: Food Contamination; Humans; Mexico; Pesticide Residues; Pesticides; Risk Assessment
PubMed: 35077103
DOI: 10.21149/12297 -
Biosensors & Bioelectronics Mar 2022Large-area surface-enhanced Raman spectroscopy (SERS) sensing platforms displaying ultrahigh sensitivity and signal uniformity have potentially enormous sensing...
Large-area surface-enhanced Raman spectroscopy (SERS) sensing platforms displaying ultrahigh sensitivity and signal uniformity have potentially enormous sensing applicability, but they are still challenging to prepare in a scalable manner. In this study, silver nanopaste (AgNPA) was employed to prepare a wafer-scale, ultrasensitive SERS substrate. The self-generated, high-density Ag nanocracks (NCKs) with small gaps could be created on Si wafers via a spin-coating process, and provided extremely abundant hotspots for SERS analyses with ultrahigh sensitivity-down to the level of single molecules (enhancement factor: ca. 10; detection limit: ca. 10 M)-and great signal reproducibility (variation: ca. 3.6%). Moreover, the Ag NCK arrays demonstrated broad applicability and practicability for on-site detection when combined with a portable 785 Raman spectrometer. This method allowed the highly sensitive detection of a diverse range of analytes (benzo[a]pyrene, di-2-ethylhexyl phthalate, aflatoxins B1, zearalenone, ractopamine, salbutamol, sildenafil, thiram, dimethoate, and methamidophos). In particular, pesticides are used extensively in agricultural production. Unfortunately, they can affect the environment and human health as a result of acute toxicity. Therefore, the simultaneous label-free detection of three different pesticides was demonstrated. Finally, the SERS substrates are fabricated through a simple, efficient, and scalable process that offers new opportunities for mass production.
Topics: Biosensing Techniques; Humans; Metal Nanoparticles; Reproducibility of Results; Silver; Spectrum Analysis, Raman; Thiram
PubMed: 34973566
DOI: 10.1016/j.bios.2021.113920 -
Environmental and Molecular Mutagenesis Jan 2022We previously showed that farmers in Bolivia are exposed to many pesticides, some at elevated levels, and that this was associated with increased risk of genetic damage....
We previously showed that farmers in Bolivia are exposed to many pesticides, some at elevated levels, and that this was associated with increased risk of genetic damage. To improve the understanding of possible mixture effects, the cytotoxicity and genotoxicity of pesticides were studied in vitro using human liver HepG2 cells. The studied pesticides were 2,4-D, chlorpyrifos, cypermethrin, glyphosate, methamidophos, paraquat, profenofos, and tebuconazole. Three mixtures (U1, U2, and U3) were based on profiles of urinary pesticide metabolites and one mixture on the most frequently used pesticides (S1). The results showed that paraquat and methamidophos were the most cytotoxic pesticides (EC ≤0.3 mM). Paraquat, chlorpyrifos, tebuconazole, and the U1, U2, and U3 mixtures, which contained a large proportion of either chlorpyrifos or tebuconazole, significantly increased intracellular ROS levels. Most pesticides activated DNA damage signaling through proteins Chk1 and H2AX. Strongest responses were elicited by paraquat, profenofos, chlorpyrifos, cypermethrin, and the S1 mixture, which contained 25% paraquat. Comet assay revealed significant increases of DNA damage in response to paraquat, cypermethrin, and U2 and S1 mixtures, which contained high levels of cypermethrin and paraquat, respectively. In summary, we showed that the tested pesticides, alone or in mixtures, in general induced oxidative stress and that most pesticides, and especially paraquat and cypermethrin, were genotoxic in HepG2 cells. We could also show that mixtures dominated by these two pesticides displayed a marked genotoxic potency, which agreed with our previous population studies.
Topics: Bolivia; Chlorpyrifos; DNA Damage; Farmers; Humans; Paraquat; Pesticides
PubMed: 34881454
DOI: 10.1002/em.22468 -
Integrated Environmental Assessment and... Sep 2022Intact soil food webs are pivotal to maintaining essential soil functions, such as carbon recycling, sequestering, and biomass production. Although the functional role...
Intact soil food webs are pivotal to maintaining essential soil functions, such as carbon recycling, sequestering, and biomass production. Although the functional role of micro- (e.g., bacteria and fungi) and macrofauna (e.g., earthworms) is comparatively well established, the importance of the mesofauna community (e.g., abundance and diversity of Acari and Collembola) in maintaining soil functionality is less clear. We investigated this question in a six-month field experiment in arable soil by actively manipulating mesofauna abundance and biodiversity through the application of two legacy insecticides (lindane and methamidophos) at sufficiently high doses to reduce mesofauna abundance (well above previously registered application rates; 2.5 and 7.5 kg a.s./ha for lindane, and 0.6 and 3 kg a.s./ha for methamidophos) and measure the impact on organic matter degradation. Our results demonstrate that both insecticides had reduced Collembola and Acari abundances by up to 80% over the study's six-month duration. In addition, we observed less pronounced and more complex changes in mesofauna biodiversity over time. These included insecticide-dependent temporal fluctuations (both reduction and increase) for different estimates (indices) of local (alpha)-diversity over time and no lasting impact for most estimates after six months. Even at these exceptionally high field rates, Collembola and Acari diversity was observed to generally recover by six months. In contrast, considering organic matter breakdown, we found no evidence of a treatment-related effect. These results suggest that organic matter breakdown in arable soils is likely driven by other trophic levels (e.g., microorganisms or earthworms) with only a limited influence of the mesofauna community. We discuss these findings with regard to their implications for our current understanding of soil food web function and future European soil risk assessments. Integr Environ Assess Manag 2022;18:1423-1433. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
Topics: Animals; Arthropods; Biodiversity; Food Chain; Hexachlorocyclohexane; Insecticides; Oligochaeta; Soil
PubMed: 34878731
DOI: 10.1002/ieam.4563 -
Journal of Hazardous Materials Mar 2022The microbial degradation of acephate in pure cultures has been thoroughly explored, but synergistic metabolism at the community level has rarely been investigated....
The microbial degradation of acephate in pure cultures has been thoroughly explored, but synergistic metabolism at the community level has rarely been investigated. Here, we report a novel microbial consortium, ZQ01, capable of effectively degrading acephate and its toxic product methamidophos, which can use acephate as a source of carbon, phosphorus and nitrogen. The degradation conditions with consortium ZQ01 were optimized using response surface methodology at a temperature of 34.1 °C, a pH of 8.9, and an inoculum size of 2.4 × 10 CFU·mL, with 89.5% of 200 mg L acephate degradation observed within 32 h. According to the main products methamidophos, acetamide and acetic acid, a novel degradation pathway for acephate was proposed to include hydrolysis and oxidation as the main pathways of acephate degradation. Moreover, the bioaugmentation of acephate-contaminated soils with consortium ZQ01 significantly enhanced the removal rate of acephate. The results of the present work demonstrate the potential of microbial consortium ZQ01 to degrade acephate in water and soil environments, with a different and complementary acephate degradation pathway.
Topics: Biodegradation, Environmental; Microbial Consortia; Organothiophosphorus Compounds; Phosphoramides; Soil; Soil Microbiology
PubMed: 34844804
DOI: 10.1016/j.jhazmat.2021.127841 -
Food Chemistry May 2022A method for the determination of 80 pesticides (including five metabolites) in passion fruit using ethyl acetate extraction and dispersive solid-phase extraction...
A method for the determination of 80 pesticides (including five metabolites) in passion fruit using ethyl acetate extraction and dispersive solid-phase extraction followed by LC-MS/MS and GC-MS/MS was validated at LOQ of 0.005 or 0.010 mg kg (70 to 120% recovery; RSD ≤ 20%). Fifty-five passion fruit samples were obtained from producers, and 30 samples of frozen pulp and 12 samples of flour purchased. About 27% of the pesticides were detected; at least one in 60% of the peel samples, mainly imidacloprid and carbendazim (max. of 0.274 mg kg). Median processing factor was 0.5 for washed peel and 6.5 for dried peel (flour). About 63% of frozen pulp samples were positive, and 4 flour samples contained residues, mainly methamidophos. About 70% of the detected pesticides are not authorized in passion fruit in Brazil. Chronic and acute exposure from the consumption of passion fruit products did not indicate a health concern.
Topics: Chromatography, Liquid; Fruit; Gas Chromatography-Mass Spectrometry; Passiflora; Pesticide Residues; Risk Assessment; Tandem Mass Spectrometry
PubMed: 34836670
DOI: 10.1016/j.foodchem.2021.131643 -
Scientific Reports Nov 2021Toxicity of organophosphorus compounds (OPs) remains a major public health concern due to their widespread use as pesticides and the existence of nerve agents. Their...
Toxicity of organophosphorus compounds (OPs) remains a major public health concern due to their widespread use as pesticides and the existence of nerve agents. Their common mechanism of action involves inhibition of enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) which are crucial for neurotransmission. Both chronic and acute poisoning by OPs can leave long-lasting health effects even when the patients are treated with standard medical therapy. Therefore, an increasing urgency exists to find more effective oxime reactivators for compounds which are resistant to reactivation, especially phosphoramidates. Here, we investigated in silico and in vitro interactions and kinetics of inhibition for human cholinesterases with four organophosphate pesticides-ethoprophos, fenamiphos, methamidophos and phosalone. Overall, ethoprophos and fenamiphos displayed higher potency as inhibitors for tested cholinesterases. Our results show that methamidophos-inhibited hAChE was more susceptible to reactivation than hAChE inhibited by fenamiphos by selected oximes. Molecular modelling enabled an evaluation of interactions important for specificity and selectivity of both inhibition and reactivation of cholinesterases. Two newly developed reactivators-bispyridinium triazole oxime 14A and zwitterionic oxime RS194B possess remarkable potential for further development of antidotes directed against pesticides and related phosphoramidate exposures, such as nerve agents tabun or Novichoks.
Topics: Acetylcholinesterase; Butyrylcholinesterase; Cholinesterase Inhibitors; GPI-Linked Proteins; Humans; Kinetics; Organophosphorus Compounds; Pesticides
PubMed: 34728713
DOI: 10.1038/s41598-021-00953-9 -
Toxics Oct 2021In recent years, the official authorities in Chile have reported transgressions in the maximum residue levels of pesticides in fresh vegetables. There is no official...
In recent years, the official authorities in Chile have reported transgressions in the maximum residue levels of pesticides in fresh vegetables. There is no official information about traceability, pesticide levels, and potential health risks. The aim of this study was to analyse pesticide residues and their corresponding dietary risk assessments in tomatoes from supermarkets in the Metropolitan Region. Pesticides were extracted using the Quick, Easy, Cheap, Effective, Rugged and Safe, QuEChERS method, and their concentrations were determined by using chromatography with HPLC-FL/UV and GC-MS/ECD/NPD, following the Analytical Quality Control and Method Validation Procedures for Pesticides Residues Analysis in Food and Feed, SANTE guide and ISO 17025:2017 standard. In addition, a dietary risk assessment was carried out by comparing Chilean data to international references. The results reported that 9% of the samples had pesticide residue levels above the maximum residue levels permitted in Chile. All the scenarios evaluated revealed the highest estimated daily intake and hazard quotients for methamidophos and chlorpyrifos. Both the active substances used were acetylcholinesterase inhibitors and were neurotoxic under chronic risk assessment. The results showed the highest chronic hazard index in the Chilean scenario for all age groups and genders. The evidence obtained revealed that methamidophos, methomyl, and chlorpyrifos should be restricted for their use in Chilean agriculture.
PubMed: 34678945
DOI: 10.3390/toxics9100249 -
The Science of the Total Environment Feb 2022Enantioselective metabolism of chiral pesticide in plants is very important. In vitro system has become an effective means to study the metabolism of pesticides in...
Enantiomer metabolism of acephate and its metabolite methamidophos in in vitro tea (Camellia sinensis L.) systems: Comparison between cell suspensions and excised tissues.
Enantioselective metabolism of chiral pesticide in plants is very important. In vitro system has become an effective means to study the metabolism of pesticides in plants, but the study on the metabolism of chiral pesticides has not been reported. This work compared the enantiomer metabolic behavior of acephate and its metabolite methamidophos between tea cell suspensions and excised tea stem with leaves. (±)-Acephate could be absorbed and transferred well to top leaves by the cut end of excised stem after 24 h. (±)-Methamidophos was derived from the metabolism of (±)-acephate in tea plants at 3-5% in leaves and 2-3% in stems at 216 h. The content of (+)-methamidophos was 1.5 times higher than that of (-)-methamidophos in excised leaves. Though both (±)-acephate and (±)-methamidophos could be metabolized well by cell suspension, (±)-acephate and (±)-methamidophos was non-enantioselectively metabolized in cell suspension. It was shown that using the excised tea stem with leaves for chiral pesticide metabolism studies was much closer to intact plant than cell suspensions. This result also established an effective and easily available in vitro metabolic model for the study of enantioselective metabolism of chiral contaminants from environment.
Topics: Camellia sinensis; Insecticides; Organothiophosphorus Compounds; Phosphoramides; Plant Leaves; Stereoisomerism; Suspensions; Tea
PubMed: 34626633
DOI: 10.1016/j.scitotenv.2021.150863 -
F1000Research 2020: Developmental delay among children under 5 years of age is a serious global public health problem and much research has been carried out to find potential causes....
: Developmental delay among children under 5 years of age is a serious global public health problem and much research has been carried out to find potential causes. Pesticides - especially organophosphates - are suspected to be one of the main causes of the problem. This study aimed to investigate the association between pesticide use by the mother during pregnancy and preschool children development using a case-control study. : Data on prenatal and postnatal pesticide exposure of 442 children with suspected developmental delay, and 413 controls with normal development were included for analysis. The children were matched for gender, age, and residency. Data on pesticide exposure were collected via interview with the mother, and data on pregnancy outcomes abstracted from hospital records. : Chlorpyrifos exposure significantly increased the risk of developmental delay with an odds ratio (OR) of 3.71 (95% CI 1.03-13.36) for ever use of the pesticide, and an OR of 5.92 (95% CI 1.01-34.68) for postnatal exposure (p <0.05). Some other pesticides also had a positive association with developmental delay but none were statistically significant (p <0.05). Those pesticides were insecticide, fungicide, herbicide, and molluscicide. Individual pesticides with a positive association were glyphosate, paraquat, butachlor, methyl parathion (pholidon), savin, methomyl, endosulfan, carbosulfan, methamidophos, monochrotofos, mancozeb, and bordeaumixture. : This case-control study found that chlorpyrifos and some other pesticides exposure during pregnancy were positively associated with developmental delay in children aged under 5 years. Further research should be conducted to better understand this potential effects of pesticides on child neurodevelopment, and the public - especially those who plan to have families - should be informed.
Topics: Case-Control Studies; Child, Preschool; Chlorpyrifos; Female; Humans; Pesticides; Pregnancy; Pregnancy Outcome; Thailand
PubMed: 34557296
DOI: 10.12688/f1000research.27874.5