Pesticide Compounds Research Articles

Novel in silico screening system for plant defense activators using deep learning-based prediction of reactive oxygen species accumulation

BackgroundPlant defense activators offer advantages over pesticides by avoiding the emergence of drug-resistant pathogens. However, only a limited number of compounds have been reported. Reactive oxygen species (ROS) act as not only antimicrobial agents but also signaling molecules that trigger immune responses. They also affect various cellular processes, highlighting the potential ROS modulators as plant defense activators. Establishing a high-throughput screening system for ROS modulators holds great promise for identifying lead chemical compounds with novel modes of action (MoAs).ResultsWe established a novel in silico screening system for plant defense activators using deep learning-based predictions of ROS accumulation combined with the chemical properties of the compounds as explanatory variables. Our screening strategy comprised four phases: (1) development of a ROS inference system based on a deep neural network that combines ROS production data in plant cells and multidimensional chemical features of chemical compounds; (2) in silico extensive-scale screening of seven million commercially available compounds using the ROS inference model; (3) secondary screening by visualization of the chemical space of compounds using the generative topographic mapping; and (4) confirmation and validation of the identified compounds as potential ROS modulators within plant cells. We further characterized the effects of selected chemical compounds on plant cells using molecular biology methods, including pathogenic signal-triggered enzymatic ROS induction and programmed cell death as immune responses. Our results indicate that deep learning-based screening systems can rapidly and effectively identify potential immune signal-inducible ROS modulators with distinct chemical characteristics compared with the actual ROS measurement system in plant cells.ConclusionsWe developed a model system capable of inferring a diverse range of ROS activity control agents that activate immune responses through the assimilation of chemical features of candidate pesticide compounds. By employing this system in the prescreening phase of actual ROS measurement in plant cells, we anticipate enhanced efficiency and reduced pesticide discovery costs. The in-silico screening methods for identifying plant ROS modulators hold the potential to facilitate the development of diverse plant defense activators with novel MoAs.

Bioremediation of Pesticide-Contaminated Soils through Composting: Mechanisms, Factors, and Prospects

Pesticide contamination of soils poses a significant environmental and agricultural challenge on a global scale, with escalating pesticide consumption in various regions. Composting has emerged as a cost-effective and sustainable bioremediation method for pesticide-contaminated soils. This review article delves into the mechanisms, factors influencing efficiency, and the pros and cons of composting as a strategy to address pesticide pollution in soils. Pesticides enter soil environments through both point sources, such as spillage from storage or disposal areas, and non-point sources, including intensive agricultural use and household applications. The physical and chemical characteristics of pesticides, coupled with soil factors like permeability and particle size, influence their fate and behavior in soils. Composting, as a bioremediation method, offers several advantages, including complete destruction of pesticide compounds through microbial degradation, transforming them into less hazardous products. Key factors affecting composting efficiency include nutrient availability, particle size, temperature, pH, oxygen, and moisture content, all crucial for microorganism growth and pesticide degradation. This article underscores the importance of maintaining optimal conditions for these factors to ensure the high performance and efficiency of pesticide degradation during composting. It also discusses the potential drawbacks of this method. Composting proves to be a promising and eco-friendly approach for remediating pesticide-contaminated soils, addressing both environmental concerns and the need for sustainable agricultural practices.

Honey bee Apis mellifera L. responses to oxidative stress induced by pharmacological and pesticidal compounds

The western honey bee, Apis mellifera L., is a eusocial insect that plays a significant role in ecosystem balances and the pollination of plants and food crops. Honey bees face multiple biotic and abiotic stressors, such as pathogens, diseases, chemical pesticides, and climate change, which all contribute to honey bee colony loss. This study investigated the impacts of multiple pharmacological and pesticidal molecules on honey bee survival and gene regulation responses. In an 11-day cage experiment, sublethal doses of tunicamycin, thapsigargin, metformin, paraquat, hydrogen peroxide, and imidacloprid were administered to newly emerged sister bees. Daily treatment consumption and mortality were recorded, as well as the transcription expression of 12 major genes (AChE-2, Apisimin, Apidaecin, mrjp1, Sodq, cp450, SelT, SelK, Ire1, Xbp1, Derl-1, and Hsc70), some of which are markers of oxidative and endoplasmic reticulum (ER) stresses in honey bees. At day 9 of the treatments, protein damage was quantified in caged bees. A Kaplan–Meier model indicated significant (p < 0.001) toxicological effects of paraquat, H2O2, and tunicamycin on bee survivorship compared with controls with better survival for other molecules. Post-ingestive aversion responses were recorded only for tunicamycin, hydrogen peroxide, and imidacloprid. Nonetheless, significantly higher protein damage on day 9 was identified only in bees exposed to paraquat and imidacloprid. Some antioxidant genes were significantly regulated vis-à-vis specific treatments. Our results reveal age-related regulation of other major genes with significant inter-gene positive correlations.

Large monitoring datasets reveal high probabilities for intermittent occurrences of pesticides in European running waters

Many studies have investigated short-term peak concentrations of pesticides in surface waters resulting from agricultural uses. However, we lack information to what extent pesticides reoccur over medium (> 4 days) and longer time periods (> 10 days). We use here large-scale pesticide monitoring data from across Europe (~ 15 mil. measurements, i.e., quantified concentrations in water at > 17,000 sites for 474 pesticide compounds) to evaluate the degree to which pesticides were not only detected once, but in sequences of a compound repeatedly quantified in the same area (0.015 km2) within 4–30 days. Reoccurrence was observed at ~ 18% of sites for > 76% of compounds, ~ 40% of which not a priori considered to chronically expose aquatic ecosystems. We calculated a probability of reoccurrence (POR) over medium-term (4–7 days) and long-term (8–30 days) time periods for ~ 360 pesticides. Relative PORs (ratio between long-term and medium-term POR) revealed three occurrence patterns: ephemeral, intermittent and permanent. While fungicides dominated intermittently occurring substances, aligning with application strategies and physico-chemical properties, neonicotinoids and legacy pesticides were among substances permanently occurring. The results of this study shed new light on previously underestimated longer-term occurrence of many pesticides in aquatic environments (35% of investigated substances occurring intermittently or permanently were previously not considered to pollute the aquatic environment chronically), entailing new challenges for chronic risk assessments and the evaluation of pesticide effects on aquatic biodiversity.

Occupational exposure to pesticides and endometrial cancer in the Screenwide case-control study

BackgroundEndometrial cancer is the most common gynaecological tumour in developed countries and disease burden is expected to increase over the years. Identifying modifiable risk factors may help developing strategies to reduce the expected increasing incidence of these neoplasms.ObjectiveThis study evaluates the association between occupational exposure to pesticides and endometrial cancer using data from a recent case-control study in Spain.MethodsThe analyses included data from 174 consecutive incident endometrial cancer cases and 216 hospital controls frequency-matched by age. Data were collected through structured epidemiological questionnaires and exposure to pesticides was assessed using a Spanish job-exposure matrix (MatEmESp).ResultsOverall, 12% of controls and 18% of cases were occupationally exposed to pesticides. We observed a positive association between occupational exposure to pesticides and endometrial cancer (OR = 2.08; 95% CI = 1.13–3.88 compared to non-exposed). In general, exposures that occurred farther in the past were significantly associated with endometrial cancer. Exposure to insecticides, fungicides and herbicides were positively associated with endometrial cancer (OR = 2.08; 95% CI = 1.13–3.88, OR = 4.40; 95% CI = 1.65–13.33, and OR = 5.25; 95% CI = 1.84–17.67, respectively). The agricultural, poultry and livestock activities scenario was associated with endometrial cancer (OR = 4.16; 95% CI = 1.59–12.32), while the cleaning exposure scenario was not (OR = 1.22; 95% CI = 0.55–2.67).ConclusionsAssessment of occupational exposure to pesticides assessed using a Spanish job-exposure matrix revealed a positive association with endometrial cancer. The elucidation of the role of pesticide compounds on endometrial cancer should shed a light on the aetiology of this tumour.

Airborne Pesticides-Deep Diving into Sampling and Analysis.

The escalating utilization of pesticides has led to pronounced environmental contamination, posing a significant threat to agroecosystems. The extensive and persistent global application of these chemicals has been linked to a spectrum of acute and chronic human health concerns. This review paper focuses on the concentrations of airborne pesticides in both indoor and outdoor environments. The collection of diverse pesticide compounds from the atmosphere is examined, with a particular emphasis on active and passive air sampling techniques. Furthermore, a critical evaluation is conducted on the methodologies employed for the extraction and subsequent quantification of airborne pesticides. This analysis takes into consideration the complexities involved in ensuring accurate measurements, highlighting the advancements and limitations of current practices. By synthesizing these aspects, this review aims to foster a more comprehensive and informed comprehension of the intricate dynamics related to the presence and measurement of airborne pesticides. This, in turn, is poised to significantly contribute to the refinement of environmental monitoring strategies and the augmentation of precise risk assessments.

The Behavior of Terbuthylazine, Tebuconazole, and Alachlor during Denitrification Process.

Pesticide compounds can influence denitrification processes in groundwater in many ways. This study observed behavior of three selected pesticides under denitrifying conditions. Alachlor, terbuthylazine, and tebuconazole, in a concentration of 0.1 mL L-1, were examined using two laboratory denitrifications assays: a "short" 7-day and a "long" 28-day test. During these tests, removal of pesticides via adsorption and biotic decomposition, as well as the efficiency of nitrate removal in the presence of the pesticides, were measured. No considerable inhibition of the denitrification process was observed for any of the pesticides. On the contrary, significant stimulation was observed after 21 days for alachlor (49%) and after seven days for terbuthylazine (40%) and tebuconazole (36%). Adsorption was in progress only during the first seven days in the case of all tested pesticides and increased only negligibly afterwards. Immediate adsorption of terbuthylazine was probably influenced by the mercuric chloride inhibitor. A biotic loss of 4% was measured only in the case of alachlor.

Fermented biochar has a markedly different effect on fate of pesticides in soil than compost, straw, and a mixed biochar-product

Current knowledge about how biochars affect the fate of pesticides in soil is based on studies that used pure biochars. After finding that an additional biological post-pyrolysis treatment, such as co-composting or lactic fermentation, is required for biochars for superior performance in temperate arable soils, a knowledge gap formed of how such further processed biochar products would affect the fate of pesticides in soil. This study compared the effects of a novel fermented biochar alone or mixed with biogas residues on the fate of two pesticides, 4-chloro-2-methylphenoxyacetic acid (MCPA) and metalaxyl-M, in a temperate arable soil to the traditional organic amendments wheat straw and compost. The fate of 14C-labeled MCPA was markedly affected in different ways. Fermented biochar effectively reduced the water-extractability and mineralization due to adsorption that was comparable to adsorption strengths reported for pure biochars. However, this effect was weak for the biochar mixed with biogas residues. Straw reduced water-extractable amounts due to increased biodegradation and formation of likely biogenic non-extractable residues of MCPA. In contrast, compost decelerated mineralization and increased the water solubility of the MCPA residues due to released dissolved organic matter. The amendments' effects were minor regarding 14C-metalaxyl-M, except for the fermented biochar which again reduced water-extractability and delayed degradation due to adsorption. Thus, the effects of the organic amendments differed for the two pesticide compounds with only the fermented biochar's effect being similar for both. However, this effect was no longer present in the mixed product containing 20% biochar. Our findings clearly show that biologically treated biochar-containing products can affect the fate of pesticides in soil very differently, also when compared to traditional organic amendments. Such impacts and their desirable and undesirable ecotoxicological implications need to be considered before the large-scale application of biochars to temperate arable soils.

A Green Bridge: Enhancing a Multi-Pesticide Test for Food by Phase-Transfer Sample Treatment Coupled with LC/MS.

The preparation and treatment of the sample has become an important part of the determination process, which directly affects the accuracy of detection. The preparation of the sample for final detection is actually a process of separation and transfer of the target to be tested from the sample matrix. The phase-transfer process of analysis and detection is the process of transferring the target substance to be measured from a complex multiphase system to a simple homogeneous system. This study shows a new phase-transfer process for food sample pretreatment in the determination of carbamate pesticides. Edible gum, xanthan gum, carrageenan, and gelatin were selected for purification testing from the perspective of eco-friendliness and safety. Phase-transfer purification process research was carried out on spinach and other foods. Compared with the commonly used QuEChERS method, the LC/MS results indicate that the straightforward carrageenan treatment process can significantly diminish the detection matrix effect and yield similarly superior detection parameters. The phase-transfer purification method with carrageenan has similar sensitivity and systematic error. The limits of detection and limits of quantitation of each pesticide compound in six plant sample substrates were 0.02-0.36 μg/kg and 0.06-1.9 μg/kg, respectively, which were lower than the residue limits here and abroad. Supplemental recoveries in six blank samples at 5, 20, and 100 μg/kg with the phase-transfer process method were better than those for the QuEChERS method. Positive determination results of actual samples using carrageenan phase-transfer purification proved that this method can be used for related detection from a practical point of view.

Pesticide effect on earthworm lethality via interpretable machine learning

Earthworms are among the most important animals (invertebrates) for soil health. Many chemical substances released into nature for agricultural development, such as pesticides, may have unwanted effects on those organisms. However, it is essential to understand the extent of the impact of chemicals on soil health first and then make the proper decisions for regulatory or commercial purposes. We hypothesize that there is an expressible quantitative structure-activity relationship (QSAR) between the structure of pesticide compounds and the acute toxicity effect of earthworm species Eisenia fetida. The description of this relationship allows for a better assessment of the impact of chemicals on the said earthworm. To describe this relationship, a dataset of chemicals was collected from open-access sources to develop a mathematical model. A novel approach, combining genetic algorithm and Bayesian optimization, was used to select structural features into the model and to optimize model parameters. The final QSAR classification model was created with the Random Forest algorithm and exhibited good prediction Accuracy of 0.78 on training set and 0.80 on test set. The model representation follows FAIR principles and is available on QsarDB.org.

Honey bees and bumble bees may be exposed to pesticides differently when foraging on agricultural areas

In an agricultural environment, where crops are treated with pesticides, bees are likely to be exposed to a range of chemical compounds in a variety of ways. The extent to which different bee species are affected by these chemicals, largely depends on the concentrations and type of exposure. We quantified the presence of selected pesticide compounds in the pollen of two different entomophilous crops; oilseed rape (Brassica napus) and broad bean (Vicia faba). Sampling was performed in 12 sites in Ireland and our results were compared with the pollen loads of honey bees and bumble bees actively foraging on those crops in those same sites. Detections were compound specific, and the timing of pesticide application in relation to sampling likely influenced the final residue contamination levels. Most detections originated from compounds that were not recently applied on the fields, and samples from B. napus fields were more contaminated compared to those from V. faba fields. Crop pollen was contaminated only with fungicides, honey bee pollen loads contained mainly fungicides, while more insecticides were detected in bumble bee pollen loads. The highest number of compounds and most detections were observed in bumble bee pollen loads, where notably, all five neonicotinoids assessed (acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam) were detected despite the no recent application of these compounds on the fields where samples were collected. The concentrations of neonicotinoid insecticides were positively correlated with the number of wild plant species present in the bumble bee-collected pollen samples, but this relationship could not be verified for honey bees. The compounds azoxystrobin, boscalid and thiamethoxam formed the most common pesticide combination in pollen. Our results raise concerns about potential long-term bee exposure to multiple residues and question whether honey bees are suitable surrogates for pesticide risk assessments for all bee species.

Long-Chain Molecules with Agro-Bioactivities and Their Applications.

Long-chain molecules play a vital role in agricultural production and find extensive use as fungicides, insecticides, acaricides, herbicides, and plant growth regulators. This review article specifically addresses the agricultural biological activities and applications of long-chain molecules. The utilization of long-chain molecules in the development of pesticides is an appealing avenue for designing novel pesticide compounds. By offering valuable insights, this article serves as a useful reference for the design of new long-chain molecules for pesticide applications.

Organophosphate pesticide residues in surface water and bilih fish (Mystacoleucus padangensis Blkr.) in Lake Singkarak, West Sumatra

Organophosphate pesticide is a pesticide derivate that is used widely by farmers because it has a high killing power against insects and easily disappears from plants. Organophosphate pesticide residues can accumulate in the environment and also cause acute and chronic poisoning in humans. Singkarak Lake in West Sumatra Province is surrounded by many agricultural and farming areas. One of fisheries resources that can be affected by activities at those areas is Bilih fish (Mystacoleucus padangensis). The study aims to determine the levels of organophosphate pesticide residues in Singkarak Lake’s water and Bilih fish. Seven organophosphate pesticide compounds: Diazinon, Fenitrothion, Methidathion, Malathion, Chlorpyrifos, Parathion, and Profenofos were analyzed. In June 2021, surface water and Bilih fish samples were collected from 10 sampling locations in Singkarak Lake. The organophosphate pesticide in the samples was determined using gas chromatography. The results showed that residues were detected in water samples of four locations (Ombilin, Tikalak, Sumani, and Paninggahan), but not in the other six locations (Batu Taba, Sumpur, Guguak Malalo, Saniang Baka, Muaro Pingai, and Tanjung Mutuih) as well as below 1 ppb. Methidathion, Malathion, Chlorpyrifos, and Parathion were detected in lake water at range 2 to 8 ppb. Except for the Bilih fish sample from Ombilin, the majority of the samples contained organophosphate residues. Diazinon, Fenitrothion, Methidathion, Chlorpyrifos, Parathion, and Profenofos were the organophosphate derivate found in the fish samples. Malathion compound was not found. The organophosphate residue concentration in Bilih fish ranged from 2 to 70 ppb.

Effect of pH on the optimization of cysteine‐functionalized gold core‐silver shell nanoparticles for surface‐enhanced Raman scattering‐based pesticide detection on apple peels

AbstractBackgroundThe rapid detection and efficient properties of surface‐enhanced Raman scattering (SERS) have been widely exploited in food safety.PurposeIn this study, the SERS impact of cysteine‐functionalized gold core‐silver shell bimetallic nanoparticle (Au@Ag@CysNPs) substrates with different pH treatments on pesticide compounds was examined.ResultsThe pH‐dependent SERS impact of Au@Ag@CysNPs on detecting pesticide compounds exhibited different enhancements over the pH range of 2–11 and exited the highest enhancement at a pH of 5 for thiabendazole and thiram pesticides. The prepared Au@Ag@CysNPs were further utilized in SERS‐based rapid detection of pesticides on apple peels by directly dropping Au@Ag@CysNPs on the surface of the samples, where the target molecules could be identified without elution or extraction. These findings revealed that this Au@Ag@CysNPs substrate exhibited excellent SERS performances for pesticide compounds and good stability. With additional optimization, detection limits of 0.1 ng/cm2 for thiabendazole and thiram on apple peels were obtained.

O-091 The impact of endocrine disruptors on early pregnancy and clinical outcomes in IVF

Abstract The impact of endocrine disruptors on early pregnancy and clinical outcomes in IVF Moncef Benkhalifa (1,2,3), Debbie Montjean (2), Hafida Corsi-Cauet (3), Henri Copin (1,3), Véronique Bach (3), Pierre Miron (2), Rosalie Cabry (1,3) (1) Reproductive Medicine and Reproductive Genetics, University Hospital & School of Medicine. Picardie University Jules Verne. Amiens France (2) ART Centers. Laval and Brossard. Fertilys International Inc. Laval. Québec. Canada (3) PERITOX Laboratory. Picardie University Jules Verne. Amiens. France Since more than 40 years, there are annual increasing of studies, meta-analysis reporting and discussing the potential associations between endocrine disrupting chemicals (EDCs) and human fertility potential declining. Today it’s accepted that a substantial number of environmental and exposition factors affect the fertility and fecundity capacity of couples during the peri and post conception period. It’s accepted that most of EDCs interfere with or mimic steroid hormone action; predominantly by affecting estrogen, androgen and thyroid hormones signaling pathways and disturbing specific molecular process on relation with single or multiple biological functions. Some of EDCs can interact with the male and female reproductive system and lead to endocrine disruption in the testis and ovary. they exert their effects mainly via binding transcription factor receptors, EDCs can alter endocrine function through a variety of mechanisms. At fertility age EDCs may alter the expression and/or activity of enzymes required for synthesis and/or catabolism of testicular and ovarian sex steroids and the expression of hormone receptors and/or their ability to bind their and endogenous ligands. For example, in male, the literature reported a negative correlation between disrupted spermatogenesis and lifestyle factors (environmental-professional expositions) such as alcohol consumption, cigarette smoking, drug use, and obesity caused by high-energy diet. In female infertility diseases, the negative impact of chemicals ED has been studied in animals. Many disorders have been described, such as low ovarian weight, impaired folliculogenesis, a high aneuploidy rate and the acceleration of follicular atresia. Indeed, women exposed to some endocrine-disrupting pesticides (such as atrazine, lindane) have an elevated risk of long menstrual cycles or anovulation but the most serious consequence is POF and endometriosis pathophysiology’s. In our IVF experience in Picardie region (France), we observed that various pesticides with an endocrine-disrupting action are associated with poor oocyte quality (maturation and competency), embryonic defects and poor IVF outcomes, and some pesticide compounds are linked to specific causes of female infertility, such as premature ovarian insufficiency, polycystic ovarian syndrome, and endometriosis. It was reported that EDCs can reduce embryo implantation chances and increase miscarriage, placenta and post-natal abnormalities. for endometrium receptivity and implantation failure EDCs can play by modifying keys elements of the immune response relevant to pregnancy, and disrupt immune tolerance required for robust placentation, optimal fetal development and be a as contributing risk factors in recurrent miscarriage, preeclampsia, preterm birth and related pathologic gestation Environmental insults, including endocrine disrupting chemicals during critical periods of fetal development, can alter DNA methylation patterns, leading to inappropriate developmental gene expression and disease risks. Similar to environmental factors, endocrine-disrupting chemicals can influence gene expression without modifying the DNA sequence. It is commonly accepted that the transgenerational inheritance of parentally acquired traits is conveyed by epigenetic alterations risks also known as “epimutations”. In Conclusion, the negative impact of exposure to various endocrine-disrupting is becoming now a worldwide public health. Indeed, the community should be informed about the fertility decline, low ongoing pregnancy rates, and elevated risk of miscarriage associated with exposure to high doses of pesticides for example. We must keep in mind that humans are exposed to EDCs mixtures composed of hundreds of chemicals every day and not a single chemical in isolation.

Selenium alleviates biological toxicity of thiamethoxam (TMX): Bioaccumulation of TMX, organ damage, and antioxidant response of red swamp crayfish (Procambarus clarkii)

Pesticides are important for agricultural development; however, animals involved in rice-fish farming absorb the pesticides used during the farming process. Thiamethoxam (TMX) is extensively used in agriculture and is gradually occupying the market for traditional pesticides. Therefore, this study aimed to investigate whether selenomethionine (SeMet) could affect the survival rate, bioaccumulation of TMX, serum biochemical parameters, lipid peroxidation, antioxidants in the hepatopancreas, and expression of stress genes after exposure of red swamp crayfish to 10 ppt TMX for 7 days. The results showed that the survival rate significantly increased and the bioaccumulation of TMX significantly decreased with SeMet administration (P < 0.05). Furthermore, severe histological damage to the hepatopancreas of red crayfish was observed after exposure to TMX; however, this damage was alleviated after SeMet administration. SeMet also significantly reduced the TMX-induced changes in serum biochemical parameters, malondialdehyde content, and antioxidant enzyme activity in crayfish hepatopancreas (P < 0.05). Notably, analysis of the expression of 10 stress response genes showed that 0.5 mg/kg SeMet might decrease cell damage in the hepatopancreas. Consequently, our findings suggest that higher levels of TMX in crayfish may cause hepatopancreatic cell toxicity, which can be harmful to human health; however, SeMet could mitigate these effects, providing an understanding of pesticide compounds and food safety.

Assessment of environmental and human health risk from pesticide residues in river Gomti, Northern India.

Rivers get polluted with diverse types of hazardous and toxic substances, pesticides being one of them. The water and sediment of rivers get contaminated with pesticide residues coming through the run-off of vast agricultural fields along the catchment area and also from domestic sewage water. The residues get bio-concentrated and bio-accumulated in different aquatic organisms and animals including fishes along the food chain. Fish, one of the important and chief sources of proteins, are consumed by humans. The presence of toxic substances like pesticides in any food item is undesirable for the fear of health hazards. We have monitored the status of pesticide residue in river Gomti, a tributary of River Ganga that passes through the Uttar Pradesh state of India. Water, sediment, and fish samples collected from the different locations along the river stretch were analyzed for 34 targeted pesticide compounds belonging to organochlorines (OC), organophosphates (OP), and synthetic pyrethroids (SP) groups. In 52% of water, 30% of sediment, and 43% of fish samples residues of OCs were detected while the OPs were present in 33%, 25%, and 39% of samples respectively. However, none of the SPs could be recorded in any sample. The concentrations of the pesticides in water indicate stress conditions to some extent to aquatic life, but based on the human health risk assessment it can be concluded that consumption of fishes from the river contaminated with different OC or OP residues would not pose any direct risk to the consumers.

Maternal pesticide exposure and risk of preterm birth: A systematic review and meta-analysis

BackgroundMaternal pesticide exposure might be associated with adverse pregnancy outcomes through triggering inflammation and oxidative stress and disrupting endocrine functions. Yet the association between prenatal pesticide exposure and risk of preterm birth remains inconclusive. ObjectivesTo conduct a systematic review and meta-analysis of human observational studies using the Office of Health Assessment and Translation (OHAT) framework to explore the association of per ten-fold increase of pesticide concentrations in maternal biological samples during pregnancy with risk of preterm birth and length of gestational age at birth. Data sourceFive English (PubMed, Embase, Cochrane Library, Web of Science and Scopus) and 3 Chinese databases (China national knowledge infrastructure (CNKI), Wanfang Data, and Chinese Biomedical Literature Database (CBM)) were searched till Jan 18th, 2023. Study eligibility criteria, participants, and interventionsTo be included, pesticide exposure should be measured in maternal biological samples during pregnancy and in log-transformed forms. The primary outcome was preterm birth and the secondary outcome was gestational age at birth. Study appraisal, synthesis methods and confidence assessmentQuality of studies was evaluated using OHAT Risk of Bias Tool. Evidence was quantitatively synthesized with Correlated and Hierarchical Effects (CHE) model. The confidence rating in the body of evidence was done using OHAT. ResultsA total of 21 studies reported by 18 papers were included, with 7 studies for preterm birth and 19 for gestational age at birth. The meta-analysis found a ten-fold increase of pesticide concentrations was potentially associated with risk of preterm birth (pooled OR = 1.28; 95%CI: 0.93, 1.78) and shortened gestational age at birth (β = −0.10; 95%CI: −0.21, 0.01). Sampling biospecimens in different trimesters was identified as a potential modifier in the association between pesticide exposure and length of gestational age (F = 2.77, P < 0.05). For studies that collected samples at any time during pregnancy, pesticide exposure was found to be associated with shortened length of gestational age (β = −0.43; 95%CI: −0.81, −0.06). The confidence rating in the body of evidence was “moderate” and “very low” for preterm birth and gestational age at birth, respectively. ConclusionOur result suggested moderate evidence of an association between pesticide exposure and higher risk of preterm birth. Yet more studies are still needed with larger sample size and careful considerations of confounders and accuracy of outcome measurements. Attention is also required on other pesticide compounds in addition to organochlorine and organophosphorus pesticides, and on windows of susceptibility.

Predictive Quantitative Read-Across Structure-Property Relationship Modeling of the Retention Time (Log tR) of Pesticide Residues Present in Foods and Vegetables.

The retention time (log tR) of pesticidal compounds in a reverse-phase high-performance liquid chromatography (HPLC) analysis has a direct relationship with lipophilicity, which could be related to the ecotoxicity potential of the compounds. The novel quantitative read-across structure-property relationship (q-RASPR) modeling approach uses similarity-based descriptors for predictive model generation. These models have been shown to enhance external predictivity in previous studies for several end points. The current study describes the development of a q-RASPR model using experimental retention time data (log tR) in the HPLC experiments of 823 environmentally significant pesticide residues collected from a large compound database. To model the retention time (log tR) end point, 0D-2D descriptors have been used along with the read-across-derived similarity descriptors. The developed partial least squares (PLS) model was rigorously validated by various internal and external validation metrics as recommended by the Organization for Economic Co-operation and Development (OECD). The final q-RASPR model is proven to be a good fit, robust, and externally predictive (ntrain = 618, R2 = 0.82, Q2LOO = 0.81, ntest = 205, and Q2F1 = 0.84) that literally outperforms the external predictivity of the previously reported quantitative structure-property relationship (QSPR) model. From the insights of modeled descriptors, lipophilicity is found to be the most important chemical property, which positively correlates with the retention time (log tR). Various other characteristics, such as the number of multiple bonds (nBM), graph density (GD), etc., have a substantial and inversely proportionate relationship with the retention time end point. The software tools utilized in this study are user-friendly, and most of them are free, which makes our methodology quite cost-effective when compared to experimentation. In a nutshell, to obtain better external predictivity, interpretability, and transferability, q-RASPR is an efficient technique that has the potential to be employed as a good alternative approach for retention time prediction and ecotoxicity potential identification.

Phenotypic and Biomechanical Characteristics of Human Fetal Neural Progenitor Cells Exposed to Pesticide Compounds

Various forms of pesticides have been reported to be among the environmental toxicants, which are detrimental to human health. The active ingredients of these formulations can enter the human body through air, food, or water. Epidemiological studies suggest that these compounds strongly affect the developing brain in fetal and infant stages due to their ability to breach the underdeveloped blood–brain barrier. Since neural progenitor stem cells (NPCs) in the developing brain are the most vulnerable to these compounds, the mechanisms by which NPCs experience toxicity upon exposure to these chemicals must be investigated. Here, we assessed the viability of human fetal NPCs in 2D cultures in the presence of the active ingredients of six widely used pesticides using Live/Dead® and Hoechst staining. The IC50 values ranged from 4.1–201 μM. A significant drop in cell viability with increasing toxicant concentration (p &lt; 0.01) was noted, with the order of toxicity being malathion &lt; 4-aminopyridine &lt; methoprene &lt; prallethrin &lt; temephos &lt; pyriproxyfen. Changes in cellular biomechanical characteristics (Young’s modulus, tether force, membrane tension, and tether radius) were quantified using atomic force microscopy, whereas cell migration was elucidated over 48 h using a customized wound-healing assay. The Young’s modulus of fetal NPCs exposed to IC50/2 doses of these compounds was reduced by 38–70% and that of those exposed to IC50 doses was reduced by 71–80% (p &lt; 0.001 vs. controls for both; p &lt; 0.01 for IC50 vs. IC50/2 for each compound). Similar patterns were noted for tether forces and membrane tension in fetal NPCs. NPC migration was found to be compound type- and dose-dependent. These results attest to the significant detrimental effects of these compounds on various aspects of the human fetal NPC phenotype, and the utility of cell mechanics as a marker to assess developmental neurotoxicity.