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Contrary to the initial hypothesis, Flemish adolescents who reported consuming organic food at least 7.5 times per week did not exhibit reduced internal exposure to the tested recently used pesticides. After adjustment for gender, age, country of origin, socioeconomic status, body mass index, consumption of high-fat foods and foods linked to organic food consumption, and concerning organochlorine derivatives and lead, additional adjustment for the duration of breastfeeding expressed in weeks, they displayed slightly elevated internal exposure to organochlorine derivatives, lead, methyl arsenate, and toxic relevant arsenic. A comparison was also made between the correlation of internal exposure to pollutants with the frequency of organic food consumption on one hand and the total consumption of equivalent products from all sources on the other. Regarding potatoes, vegetables, and fruits, no clear trends were observed. Regarding eggs, there was a trend towards higher internal exposures with organic food consumption, significant for trans-nonachlor, PCB118, and 2,4-dichlorophenoxyacetic acid, and marginally significant for glyphosate. For dairy, there was a trend towards higher internal exposures with organic food consumption, significant for perfluorononanoic acid and marginally significant for PCB153. Regarding nuts and seeds, the higher internal exposure to dichlorophenoxyacetic acid and the lower exposure to 3-phenoxybenzoic acid were marginally significant, while there was also a trend towards higher internal exposure to other pollutants with organic food consumption, significant for PCB118, PCB153, and sum PCBs, and marginally significant for trans-nonachlor. Concerning breakfast cereals and muesli, no clear trends were observed.

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The present review aimed to evaluate the current situation of pesticide residues detected in shrimp (commercial species) on the Mexican coasts. The organochlorine pesticides (OC), α-endosulfan (210.01 ng g-1), endosulfan sulfate (127.5 ng g-1), heptachlor (126.04 ng g-1 and γ-HCH (121.04 ng g-1) are identified as the most common pesticides in shrimp tissues, with the Northwest area reporting the highest concentrations of these OC. Given that there is an under-evaluation of pesticide residue levels, there was a greater contribution of studies directed at the Northwest of the country considering that there are states that are among the main shrimp-producing and consumers entities. The concentrations and types of pesticides banned nationally and globally, due to their toxic effects on the population, were reported. Therefore, since the most current information is 19 years out of date, it is necessary to perform recent evaluations with sensible and precise methods.

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Steller sea lions (SSL) are sentinels for monitoring environmental contaminants in remote areas of the Aleutian Islands, Alaska. Therefore, concentrations of several organochlorines (OCs) were measured in blood from 123 SSL pups sampled from 3 regions; the western Aleutian Islands (WAI), central Aleutian Islands (CAI), and the central Gulf of Alaska. Blood, blubber, and milk from 12 adult female SSL from WAI, CAI and southeast Alaska also were analyzed. Findings included the following. SSL pups had higher concentrations of some OCs and mercury (Hg) on rookeries in the WAI than those more easterly. Pups had significantly higher blood concentrations of many OC classes than adult females sampled within the same region; some pups had PCB concentrations exceeding thresholds of concern (∑PCBs >8600 ng/g lw). ∑PCB concentration in pup whole blood was positively correlated with the trophic marker, δ15N within the regions sampled, along with two PCB congeners (PCB138 and PCB153). This suggests that the dams of pups with higher ∑PCBs, PCB138, and PCB153 concentrations were feeding on more predatory prey. Adult female blubber ∑DDT and hexachlorocyclohexane concentrations were also positively correlated with δ15N values. Several pups (mostly from WAI) had blood Hg concentrations and/or blood PCB concentrations (surrogate for overall OC exposures) of concern. The finding that WAI SSL pups have been exposed to multiple contaminants calls for future investigation of their cumulative exposure to a mixture of contaminants especially their transplacental and then transmammary exposure routes.

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Prenatal exposures are associated with childhood asthma, and risk may increase with simultaneous exposures. Pregnant women living in lower-income communities tend to have elevated exposures to a range of potential asthma risk factors, which may interact in complex ways. We examined the association between prenatal exposures and the risk of childhood acute-care clinical encounters for asthma (hospitalizations, emergency department visits, observational stays) using conditional logistic regression with a multivariable smoothing term to model the interaction between continuous variables, adjusted for maternal characteristics and stratified by sex. All births near the New Bedford Harbor (NBH) Superfund site (2000-2006) in New Bedford, Massachusetts, were followed through 2011 using the Massachusetts Pregnancy to Early Life Longitudinal (PELL) Data System to identify children aged 5-11 years with acute-care clinical asthma encounters (265 cases among 7787 children with follow-up). Hazard ratios (HRs) were higher for children living closer to the NBH site with higher umbilical cord blood lead levels than in children living further away from the NBH site with lower lead levels (P <.001). HRs were higher for girls (HR = 4.17; 95% CI, 3.60-4.82) than for boys (HR = 1.72; 95% CI, 1.46-2.02). Our results suggest that prenatal lead exposure in combination with residential proximity to the NBH Superfund site is associated with childhood asthma acute-care clinical encounters. This article is part of a Special Collection on Environmental Epidemiology.

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The Adriatic Sea plays a crucial role as both a significant fishing ground and a thriving trading market for small pelagic edible fish. Recognized for their nutritional value, these fish are esteemed for their high protein content and abundance of polyunsaturated omega-3 and omega-6 fatty acids, making them a sought-after and healthful food choice. Nevertheless, pelagic species can also serve as a reservoir for lipophilic organochlorine pollutants, posing potential risks to human health. In this study, we compared traditional classification methods traditional principal component analysis (PCA) and Ward's clustering with an advanced self-organizing map (SOM) algorithm in determining distribution patterns of 24 organochlorines and 19 fatty acids in sardine and anchovy samples taken from the eastern Adriatic. The outcomes reveal the strengths and weaknesses of the three approaches (PCA, Ward's clustering, and SOM). However, it is evident that SOM has proven to be the most effective in offering detailed information and data visualization. Although sardines and anchovies exhibit similar distribution patterns for p,p'-DDE, PCB-28, PCB-138, PCB-153, PCB-118, and PCB-170, they differ in the concentrations of fatty acids such as stearic, palmitic, myristic, oleic, docosapentaenoic, and docosahexaenoic acid. Our findings supply valuable insights for environmental authorities and fish consumers concerning the potential risks associated with organochlorines in these two types of fish.

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Ocean contamination, particularly from persistent organic pollutants (POPs), remains a significant threat to marine predators that occupy high trophic positions. Long-lived procellariform seabirds are apex predators in marine ecosystems and tend to accumulate contaminants. Prolonged exposure to pollutants negatively affects their fitness including reproductive success. Low breeding success may represent a hurdle for the restoration of small and endangered seabird populations, including several highly threatened gadfly petrels. Here we investigated the annual variation (2019 and 2022) in organochlorine pesticide (OCP), polychlorinated biphenyl ether (PCB), polybrominated diphenyl ether (PBDE), and polycyclic aromatic hydrocarbon (PAH) exposure in the endangered Bermuda petrel (Pterodroma cahow), and the relationship between female contaminant burden and breeding parameters. We found that petrels were exposed to a wide range of pollutants (33 out of 55 showed measurable levels) with PCBs dominating the blood contaminant profiles in both years. Only 9 compounds were detected in >50 % of the birds. Specifically, among OCPs, p, p'-DDE and hexaclorobenzene were the most frequently detected while fluorene and acenaphthene were the most common PAH. The concentrations of ∑5PCBs and ∑7POPs were higher in older birds. Furthermore, females with greater contaminant burdens laid eggs with a lower probability of hatching. However, female investment in egg production (size and volume) was unrelated to their blood contaminant load. Overall, this study highlights the presence of a wide range of contaminants in the petrel's food web, and it sheds light on the potential impact of chronic exposure to sub-lethal levels of PCBs on the breeding success of seabirds. We claim that toxicological testing should be a practice integrated in the management of seabirds, particularly of endangered species to monitor how past and present anthropogenic activities impact their conservation status.

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BACKGROUND: Studies on cognitive and neurodevelopmental outcomes have shown inconsistent results regarding the association with prenatal exposure to perfluoroalkyl substance (PFAS) and organochlorines. Assessment of mixture effects of correlated chemical exposures that persist in later life may contribute to the unbiased evaluation and understanding of dose-response associations in real-life exposures. METHODS: For a subset of the 4th Flemish Environment and Health Study (FLEHS), concentrations of four PFAS and six organochlorines were measured in respectively 99 and 153-160 cord plasma samples and 15 years later in adolescents' peripheral serum by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS). Sustained and selective attention were measured at 14-15 years with the Continuous Performance Test (CPT) and Stroop Test as indicators of potential neurodevelopmental deficits. Quantile g-computation was applied to assess the joint associations between prenatal exposure to separate and combined groups of PFAS and organochlorines and performance in the CPT and Stroop Test at adolescence. Subsequently, individual effects of each chemical compound were analyzed in mixed effects models with two sets of covariates. Analytical data at birth and at the time of cognitive assessment allowed for off-setting postnatal exposure. RESULTS: In mixtures analysis, a simultaneous one-quantile increase in the natural log-transformed values of PFAS and organochlorines combined was associated with a decrease in the mean reaction time (RT) and the reaction time variability (RTV) in the CPT (ß = -15.54, 95% CI:-29.64, -1.45, and ß = -7.82, 95% CI: -14.97, -0.67 respectively) and for the mixture of PFAS alone with RT (ß = -11.94, 95% CI: -23.29, -0.60). In the single pollutant models, these results were confirmed for the association between perfluorohexanesulfonate (PFHxS) with RT (ß = -17.95, 95% CI = -33.35, -2.69) and hexachlorobenzene with RTV in the CPT (ß = -5.78, 95% CI: -10.39, -0.76). Furthermore, the participants with prenatal exposure above the limit of quantification for perfluorononanoic acid (PFNA) had a significantly shorter RT and RTV in the CPT (ß = -23.38, 95% CI: -41.55, -5.94, and ß = -9.54, 95% CI: -19.75, -0.43, respectively). CONCLUSION: Higher prenatal exposure to a PFAS mixture and a mixture of PFAS and organochlorines combined was associated with better sustained and selective attention during adolescence. The associations seemed to be driven by PFHxS and were not linked to exposure levels at the time of assessment.

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BACKGROUND: Pesticide exposure has been linked to some autoimmune diseases and colorectal cancer, possibly via alteration of gut microbiota or other mechanisms. While pesticides have been linked to gut dysbiosis and inflammation in animal models, few epidemiologic studies have examined pesticides in relation to inflammatory bowel disease (IBD). OBJECTIVES: We evaluated use of pesticides and incident IBD in 68,480 eligible pesticide applicators and spouses enrolled in the Agricultural Health Study. METHODS: Self-reported IBD cases were identified from follow-up questionnaires between enrollment (1993-1997) and 2022. We evaluated IBD incidence in relation to self-reported ever use of 50 pesticides among applicators and spouses. We also explored associations with intensity-weighted lifetime days (IWLD) of pesticide use among male applicators. Covariate-adjusted hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox regression. RESULTS: We identified 454 IBD cases, including 227 among male applicators. In analyses with applicators and spouses combined, associations were positive (HR > 1.2) for ever vs. never use of five organochlorine insecticides, three organophosphate insecticides, one fungicide, and five herbicides. HRs were highest for dieldrin (HR = 1.59, 95%CI: 1.03, 2.44), toxaphene (HR = 1.61, 95%CI: 1.17, 2.21), parathion (HR = 1.42, 95%CI: 1.03, 1.95), and terbufos (HR = 1.53, 95%CI: 1.19, 1.96). We had limited power in many IWLD of pesticide use analyses and did not find clear evidence of exposure-response trends; however, we observed elevated HRs in all tertiles of IWLD use of terbufos compared to never use (T1 vs. never use HR = 1.52, 95%CI: 1.03, 2.24; T2 vs. never use HR = 1.53, 95%CI: 1.04, 2.26; T3 vs. never use HR = 1.51, 95%CI: 1.03, 2.23). CONCLUSIONS: Exposure to specific pesticides was associated with elevated hazards of IBD. These findings may have public health importance given the widespread use of pesticides and the limited number of known modifiable environmental risk factors for IBD.

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Populations of the critically endangered white-rumped vulture (WRV) Gyps bengalensis have declined drastically due to the use of diclofenac for veterinary purposes in Indian subcontinent. Thirty-two dead WRVs collected from three states, namely Gujarat, Assam and Tamil Nadu in India between 2011 and 2014 were investigated to understand the role of diclofenac in the death, and the results were published. Furthermore, since organochlorine pesticides have been linked to long-term impact on populations in many species of birds across the globe, available tissues of 21 WRVs were tested also for six organochlorine pesticides (DDT, HCH, endosulfan, heptachlor, dieldrin and dicofol) and chlorpyrifos. All vultures were found to have had one or more detectable levels of pesticides in their tissues except one. Similarly, all the pesticides included in the study were detected in at least one of the vultures analysed. DDT (95.2%) was the most frequently detected pesticide followed by HCH (90.5%), and DDT (73.6%) contributed the most to the total pesticide load. Total pesticide load ranged between below detection limit (BDL) and 8753.4 ng/g. High levels of total pesticide load recorded in gut contents showed recent exposure to these legacy pesticides even long after their ban. However, it is perceived that studied pesticides' exposure to birds and their presence in the environment is in decreasing trend in India. Although, varying levels of pesticides were detected, all of which were below the levels reported to be toxic, and also reported earlier in the same species in India. Recorded levels may not create a problem to vultures unlike diclofenac; nevertheless, as continued exposure to the pesticides studied may lead to sub lethal effects in birds, it is prudent to monitor these pesticides along with new generation pesticides and NSAIDs in the critically endangered white-rumped vulture in India, towards its conservation.

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BACKGROUND: Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCB), they have contributed to the exposure of women to persistent organic pollutants (POPs). These compounds can cross the placental barrier and interfere with the hormonal system of newborns. AIM: To determine concentrations of OCPs and PCBs and their xenoestrogenic activity in placentas of women from the PA-MAMI cohort of Panama. METHODS: Thirty-nine placenta samples from women in the Azuero peninsula (Panama) were analyzed. Five OCPs [p-p'-dichlorodiphenyldichloroethylene (p-p'-DDE), beta-hexachlorohexane (ß-HCH), γ-hexachlorohexane (lindane), hexachlorobenzene (HCB) and mirex] and three PCB congeners (PCB-138, PCB-153 and PCB-180) were quantified in placenta extracts. The xenoestrogenic activity of extracts was assessed with the E-Screen bioassay to estimate the total effective xenoestrogen burden (TEXB). RESULTS: All placental samples were positive for at least three POP residues and >70% for at least six. The frequencies of quantified OCPs ranged from 100% for p,p'-DDE and HCB to 30.8% for ß-HCH. The highest median concentration was for lindane (380.0 pg/g placenta), followed by p,p'-DDE (280.0 pg/g placenta), and HCB (90.0 pg/g placenta). Exposure to p,p'-DDE was associated with greater meat consumption, suggesting that animal fat is a major source of exposure to DDT metabolites. The frequency of detected PCBs ranged between 70 and 90%; the highest median concentration was for PCB 138 (17.0 pg/g placenta), followed by PCB 153 (16.0 pg/g placenta). All placentas were positive in the estrogenicity bioassay with a median TEXB-α of 0.91 pM Eeq/g of placenta. Exposure to lindane was positively associated with the xenoestrogenicity of TEXB- α, whereas this association was negative in the case of exposure to PCB 153. CONCLUSIONS: To our best knowledge, this study contributes the first evidence on the presence of POPs and xenoestrogenic burden in placentas from Latin-American women. Given concerns about the consequences of prenatal exposure to these compounds on children's health, preventive measures are highly recommended to eliminate or minimize the risk of OCP exposure during pregnancy.

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Since the 1970s, wildlife managers have prioritized the recovery of Great Lakes ecosystems from contamination by Persistent Organic Pollutants (POPs). Monitoring and quantifying the region's recovery is challenged by the diversity of legacy contaminants in the environment and the lack of benchmarks for their potential biological effects. We address this gap by introducing the Wildlife Environmental Quality Index (WEQI) based on prior water and sediment quality indices. The tool summarizes, in a single score, the exposure of wildlife to harmful levels of multiple contaminants - with harmful levels set by published guidelines for protecting piscivorous wildlife from biological impacts. We applied the new index to a combined Canadian and American dataset of Herring Gull (Larus argentatus) egg data to elucidate trends in wildlife for eight legacy industrial pollutants and insecticides in the Great Lakes. Environmental quality of the Great Lakes region (as indexed by WEQI) improved by 18% between 2002 and 2017. Improvement came from reductions in both the scope of contamination (the number of guideline-exceeding contaminants) and its amplitude (the average size of guideline exceedances) at bird colonies. But recovery was unequal among lakes, with Lake Erie showing no improvement at one extreme. Weakly- or non-recovering lakes (Erie, Ontario, Huron) were marked by inconsistent improvement in scope and amplitude, likely due to ongoing loading, sediment resuspension and other stressors reported elsewhere. Fast-recovering lakes (Superior and Michigan), meanwhile, improved in both scope and amplitude. Contrasting trends and contaminant profiles (e.g., exceedances of PCBs versus DDTs) highlight the importance of lake-specific management for equalizing recoveries. Lower environmental quality at American than Canadian colonies, particularly in Lake Huron, further suggest uneven success in - and opportunities for - the binational management of wildlife exposure to legacy contaminants.

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With the increasing application of nanoscale zero-valent iron (nZVI) for in situ soil remediation, its effects on soil functionality and ecosystem need to be thoroughly evaluated. Herein, we investigated the effects of nZVI on CO2 and CH4 emissions from uncontaminated and pentachlorophenol (PCP)-contaminated soils and the underlying microbial mechanisms by designing a 68-day anaerobic soil culture experiment; thereafter, the effects of above aged nZVI on soil CO2 and CH4 emissions in the following 20 days were further studied. In the uncontaminated soil, 1-10 g/kg nZVI treatments reduced soil CO2 emission by 17.4-82.6% and increased soil CH4 emission by 10.8%-119.7%, but these effects disappeared after the nZVI was aged. The emissions of soil CO2 and CH4 were significantly inhibited by the PCP contamination (100 mg/kg) mainly due to the toxicity to related soil microorganisms. The applications of 1-10 g/kg nZVI significantly reduced CO2 emissions from the PCP-contaminated soil by 24.0-86.7%, while 10 g/kg nZVI markedly increased soil CH4 emission by 1875.4% and restored the methanogenic activity to the control level after the nZVI was aged. The 10 g/kg nZVI treatment enriched hydrogenotrophic methanogen (Methanobacterium) and organics-degrading bacteria by releasing H2, increasing soil pH, and decreasing soil Eh; the abundance of genes encoding key enzymes (Mcr, Mtr, Hdr, Mta, and Mtb) in all methanogenic pathways significantly increased after the nZVI treatment, indicating that nZVI could have a broad promoting effects on soil methanogenic processes. The findings demonstrate that the addition of nZVI for in situ remediation of organochlorines-contaminated soils will affect soil greenhouse gas emissions and provide basic data for safe nZVI applications.

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Dichlorodiphenyltrichloroethane (DDT) is an insecticide, a member of dirty dozen persistent organic pollutants, used widely in the world until it was banned in the 1970s.The banning of DDT was strengthened by the Stockholm Convention in 2001. DDT is allowed only for malaria control in Ethiopia. However, farmers are misusing DDT and applying it to Khat (Catha edulis) farming. So, this review analyzes available data in the literature on the current trend, application, occurrence, fate and effects of DDT and its metabolites, dichlorodiphenyldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE), in the chewable parts of Khat. Generally, the concentration level of DDT, DDD, and DDE, designated as DDTs, is detected in different farmlands of Ethiopia. Some of the DDTs concentrations detected are very high (141.2-973 µg/kg (Gelemso), 194.4-999 µg/kg (Aseno) and 6253-8413.3 µg/kg (Gurage), and these concentrations may indicate increasing recent unmonitored application of DDT on Khat leaves. Some of the detected concentrations of DDT in the literature were above the maximum residue limit (MRL) set by FAO/WHO (100 µg/kg) and the European Commission 10 µg/kg in vegetables and 50 µg/kg in cereals. DDT exposure of Khat chewers linked to the concentration of DDT on Khat leaves and the amount of Khat consumed. DDT might pose health risks to chewers due to chronic toxicity, bioaccumulation, persistent and endocrine disruption properties.

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Alzheimer's disease (AD) is a progressive and neurodegenerative illness which results in alterations in cognitive development. It is characterized by loss/dysfunction of cholinergic neurons, and formation of amyloid plaques, and formation of neurofibrillary tangles, among other changes, due to hyperphosphorylation of tau-protein. Exposure to pesticides in humans occurs frequently due to contact with contaminated food, water, or particles. Organochlorines, organophosphates, carbamates, pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive impairment. The aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein, and its cognitive implications in the development of AD. It was found that exposure to pesticides increased the phosphorylation of tau protein at sites Ser198, Ser199, Ser202, Thr205, Ser396 and Ser404. Contact with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta, and protein phosphatase-2A. Moreover, it altered the expression of the microtubule associated protein tau gene, and changed levels of intracellular calcium. These changes affected tau protein phosphorylation and neuroinflammation, and also increased oxidative stress. In addition, the exposed subjects had poor level of performance in tests that involved evaluation of novelty, as test on verbal, non-verbal, spatial memory, attention, and problem-solving skills.

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Chemical oxidation technologies have been notably used for the mineralization of organic pollutants from aqueous effluents, been especially relevant for the degradation of pesticides. In this context, both tebuconazole (TEB) and 2,4-dichlorophenoxyacetic acid (2,4-D) pesticides were photodegraded by a combined catalyst of TiO2 and silver nanoparticles irradiated by UV-A light (λmax = 368 nm), and the experiments were tracked by surface-enhanced Raman scattering (SERS) spectroscopy. For 2,4-D, the degradation of about 70% was observed after almost 200 min, while for TEB, a decrease of 80% of the initial concentration was observed after approximately 100 min. The SERS monitoring allowed the proposal of some by-products, such as oxidized aliphatic chain and triazole from TEB besides glycolic, glyoxylic and dihydroxyacetic acids from 2,4-D. Their toxicities were predicted through ECOSAR software, verifying that most of them were not harmful to populations of fish, Daphnia and green algae. Thus, the performed oxidative process was efficient in the photodecomposition of TEB and 2,4-D pesticides, inclusive in terms of the decreasing of the toxicity of contaminated effluents.

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Pesticides are widely employed in rice crops since the ecosystem and surroundings of paddy promote insects, weeds, and fungal and bacterial pathogens. Each commonly utilised pesticide possesses different uses. For instance, fungicides control fungal issues, herbicides curb weed growth, and insecticides destroy and repel insects. Although several ways to categorise them exist, pesticides are typically classified according to their chemical compositions. Rice production remains one of the most dominant crops grown in most Southeast Asian countries as it is a staple food. Nonetheless, the crop is highly dependent on pesticides, leading to growing concerns over the potential adverse effects of pesticides on the environment and human health. Despite the availability of numerous studies on the subject, a comprehensive understanding of the specific effects of pesticides on paddy fields in Southeast Asia is still lacking. Consequently, reviewing existing knowledge is necessary for synthesising and identifying research gaps to better inform policymakers, farmers, and other stakeholders in the agricultural sector. The objectives of the present review paper were to review the interactions between pesticides and the environment by understanding the physical and chemical properties of the chemicals, compare pesticide transportation modes in air, water, and soil and how they affect the environment, and evaluate and discuss the effects of pesticides on non-targeted organisms. This study assessed pesticide innovation reported between 1945 and 2021 for a better understanding of the utilisation of the chemicals over time. The pesticides assessed in this study were classified based on their chemical compounds, such as organochlorines, organophosphates, carbamates, and pyrethroid. This review could provide a comprehensive understanding of the interactions between pesticides and the environment and their impacts on non-targeted organisms.

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Lindane production is very ineffective since, for each ton of lindane obtained, between 6 and 10 tons of hexachlorocyclohexane (HCH) isomers and other toxic compounds are produced. Due to the disposal of these residues, contaminated zones still exist, and many dumpsites are close to rivers and water reservoirs. The current study examines the consequences of irrigating pea, maize, and alfalfa, with water containing different HCH concentrations on the accumulation of HCH in plant material and soils. The experiments were conducted on pots under controlled conditions using drinking water (as reference) and water with several HCH concentrations: 0.5 µg L-1 (the maximum threshold allowed for human consumption), 2.5 µg L-1, 5 µg L-1, and 20 µg L-1. Results showed that both surface and overhead irrigation with these HCH concentrations did not cause any toxicity effects on the considered crops. However, under overhead irrigation with HCH concentrations higher than 5 µgL-1 HCH is absorbed by maize leaves and its concentration in plant biomass surpassed the EU maximum residue level of 10 µg kg-1. In the case of fodder maize, an HCH concentration of 0.84 µg L-1 in irrigation water produced an HCH concentration in plant above 20 µg kg-1 dry matter, the upper threshold established in the Spanish legislation, that limits the use for animal feeding. In the case of alfalfa, HCH was detected in treatments with the highest HCH concentration (13 µg L-1) under surface irrigation, but concentration was below the EU maximum residue level. In conclusion, in overhead irrigated systems, water with HCH concentrations below 5 µg L-1 does not produce HCH accumulation in pea and maize grain above the maximum residue levels; however, for fodder maize, the HCH concentration in irrigation water should be controlled to avoid HCH accumulation in plants above the limit for animal feeding.

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Non-genetic prenatal exposures have been associated with schizophrenia risk. However, the role of prenatal exposure to environmental neurotoxicants in offspring schizophrenia risk has been studied in only limited instances. Polychlorinated biphenyls (PCBs) and the pesticide metabolite p,p'-dichlorodiphenyl dichloroethylene (DDE) have been linked to neurodevelopmental outcomes, including impairments implicated in schizophrenia. To determine whether prenatal maternal levels of organochlorine pollutants including PCBs or DDE are associated with schizophrenia in the offspring, an investigation was conducted in the Finnish Prenatal Study of Schizophrenia (FIPS-S), a case-control study nested in a national birth cohort. Cases were born in 1987-1991 and had at least two diagnoses of schizophrenia (ICD-10 F20; ICD-9 295) or schizoaffective disorder (ICD-10 F25; ICD-9 295.7) recorded in the national Care Register for Health Care. Each case was individually matched to a control on sex, date of birth, and residence in Finland on the date of case diagnosis. In 500 case-control pairs, PCB congeners 74, 99, 118, 138, 153, 156, 170, 180, 183, 187, and some widespread organochlorine pesticides or their metabolites including DDE were measured in archived prenatal maternal sera using gas chromatography - high triple quadrupole mass spectrometry. Maternal total PCBs were quantified as the sum of concentrations of the measured congeners. Associations with schizophrenia were examined using conditional logistic regression. Maternal PCB or DDE levels greater than the 75th percentiles of the control distributions showed no evidence of association with offspring schizophrenia (PCBs: adjusted odds ratio (aOR) = 1.13, 95 % CI = 0.85-1.50), p = 0.41; DDE: aOR = 1.08, 95 % CI = 0.80-1.45; p = 0.63). Maternal levels of either pollutant dichotomized at the 90th percentile or considered as a continuous variable also did not show evidence for association with offspring schizophrenia. This study found a lack of evidence that prenatal maternal levels of the organochlorine pollutants DDE and PCBs are associated with offspring risk of schizophrenia.

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Insecticides play a critical role in controlling the spread of insect-borne diseases and preserving crop health. These chemical substances are specifically formulated to kill or manage insect populations. Over the years, various types of insecticides have been developed, including organophosphates, carbamates, pyrethroids, and neonicotinoids, each with unique modes of action, physiological targets, and efficacy. Despite the advantages that insecticides offer, it is imperative to recognize the potential consequences on non-target species, the environment, and human health. It is therefore crucial to follow recommended label instructions and employ integrated pest management practices for the judicious use of insecticides. This review article provides an in-depth examination of the various types of insecticides, including their modes of action, physiological targets, environmental and human health impacts, and alternatives. The aim is to furnish a comprehensive overview of insecticides and to emphasize the significance of responsible and sustainable utilization.

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Ethiopia is one the major exporter of cut flowers in East Africa. However, the sector is blamed for the intensive use of pesticides which leads to exposure of workers. This study aims to investigate the level of pesticides in blood serum of flower farm workers as a predictor to occupational exposure. A cross-sectional laboratory based study was conducted in central Ethiopia among 194 flower farm workers. Blood sample were collected from 100 study participants (50 from farm workers and 50 civil servants as control). Blood-serum separation, extraction, and clean-up was performed following standard analytical methods. Ten organochlorine pesticides (OCPs) (o,p'-DDT, p,p'-DDD, p,p'-DDE, p,p'-DDT, heptachlor, heptachlor epoxide, endosulfan, dieldrin, methoxychlor, dibutychloridate), and three pyrethroids (cypermethrin, permethrin and deltamethrin) were detected in the serum of the study participants. From the detected pesticides p,p'-DDT and p,p'-DDE were observed at high mean concentration (81.5 ± 83.5, and 12.5 ± 6.7 ng/mL),(38.0 ± 31.8 and 6.84 ± 7.4 ng/mL) in the flower farm and controls, respectively. From the Mann-Whitney U-test, there is a significant difference for total DDT (P < 0.02), p,p'-DDE (P < 0.001), cypermethrin (P < 0.001), heptachlor (P < 0.04), heptachlor-epoxide (P < 0.001) and dibutyl chlorendate (P < 0.01) among the flower farm workers and controls. Multinomial regression revealed, being flower farm worker is a significant predictor of moderate to high residues of p,p'-DDE, total DDT, heptachlor-epoxide and dibutyl chlorendate. The pesticides under study were detected more frequently in the flower farm workers than controls which is an indicative for occupational exposure to pesticides and strict regulation is important for the safety of workers.