Agricultural Pesticide Exposure Research Articles

The landscape of etiological patterns of hepatocellular carcinoma and intrahepatic cholangiocarcinoma in Thailand.

Thailand is among countries with the highest global incidence and mortality rates of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). While viral hepatitis and liver fluke infections have been associated with HCC and iCCA, respectively, other environmental risk factors, overall risk factor commonality and combinatorial roles, and effects on survival have not been systematically examined. We conducted a TIGER-LC consortium-based population study covering all high-incidence areas of both malignancies across Thailand: 837 HCC, 1474 iCCA, and 1112 controls (2011-2019) were comprehensively queried on lifelong environmental exposures, lifestyle, and medical history. Multivariate logistic regression and Cox proportional hazards analyses were used to evaluate risk factors and associated survival patterns. Our models identified shared risk factors between HCC and iCCA, such as viral hepatitis infection, liver fluke infection, and diabetes, including novel and shared associations of agricultural pesticide exposure (OR range of 1.50; 95% CI: 1.06-2.11 to 2.91; 95% CI: 1.82-4.63) along with vulnerable sources of drinking water. Most patients had multiple risk factors, magnifying their risk considerably. Patients with lower risk levels had better survival in both HCC (HR 0.78; 95% CI: 0.64-0.96) and iCCA (HR 0.84; 95% CI: 0.70-0.99). Risk factor co-exposures and their common associations with HCC and iCCA in Thailand emphasize the importance for future prevention and control measures, especially in its large agricultural sector. The observed mortality patterns suggest ways to stratify patients for anticipated survivorship and develop plans to support medical care of longer-term survivors, including behavioral changes to reduce exposures.

Risk assessment of airborne agricultural pesticide exposure in humans in rural China.

Continuous exposure to airborne pesticides causes their gradual accumulation in the human body, eventually posing a threat to human health. To the best of our knowledge, risk assessment study of pesticide non-occupational exposure to residents in agricultural areas has not been conducted in China. In this study, air samples (gas and dust) were collected from inside and outside residences of seven households and an area near the field in a grain-growing area (wheat and maize rotation) for eight months, and the pesticides present were examined both qualitatively and quantitatively. Using a 95% confidence interval, 9 out of 16 pesticides were detected, namely acetamiprid, acetochlor, atrazine, flucarbazone-sodium, imidacloprid, methyldisulfuron-methyl, nicosulfuron-methyl, pendimethalin, and beta-cyhalothrin, and their safety was subsequently evaluated. The results showed that the inhalation exposure of households to beta-cyhalothrin exceeded the acceptable range in the first residential, and the excess lifetime cancer risk of acetochlor inhalation exposure in six households and area around the field exceeds 1E-6, which highlights the need to strengthen preventive screening for cancer risk.

Conserved grasslands support similar pollinator diversity as pollinator-specific practice regardless of proximal cropland and pesticide exposure.

Pollinator diversity and abundance are declining globally. Cropland agriculture and the corresponding use of agricultural pesticides may contribute to these declines, while increased pollinator habitat (flowering plants) can help mitigate them. Here we tested whether the relative effect of wildflower plantings on pollinator diversity and counts were modified by proportion of nearby agricultural land cover and pesticide exposure in 24 conserved grasslands in Iowa, USA. Compared with general grassland conservation practices, wildflower plantings led to only a 5% increase in pollinator diversity and no change in counts regardless of the proportion of cropland agriculture within a 1 km radius. Pollinator diversity increased earlier in the growing season and with per cent flower cover. Unexpectedly, neither insecticide nor total pesticide concentrations on above-ground passive samplers were related to pollinator diversity. However, pollinator community composition was most strongly related to date of sampling, total pesticide concentration, and forb or flower cover. Our results indicate very little difference in pollinator diversity between grassland conservation practices with and without wildflower plantings. Given the relatively high economic costs of wildflower plantings, our research provides initial evidence that investment in general grassland conservation may efficiently conserve pollinator diversity in temperate regions of intensive cropland agriculture.

Genotoxicity of Occupational Pesticide Exposures among Agricultural Workers in Arab Countries: A Systematic Review and Meta-Analysis.

Exposure to pesticides in Arab countries is a significant public health concern due to extensive agricultural activity and pesticide use. This systematic review aimed to evaluate the genotoxic effects of agricultural pesticide exposure in the region, identify research gaps, and assess methodological limitations. Following the PRISMA guidelines, a comprehensive search yielded five relevant studies conducted in Egypt, Syria, and Jordan. Various genotoxicity assays were employed, revealing a higher level of DNA damage in exposed compared to non-exposed individuals. Farmers exposed to pesticides exhibited a significantly higher occurrence of chromosomal translocation (t(14;18)), micronuclei, and chromosomal aberrations. However, only two studies assessed cytotoxicity indirectly. The studies predominantly focused on male participants, with variations in sample size and pesticide types. The lack of detailed exposure data necessitates cautious interpretation. This review underscores the need for further research on the genotoxicity of occupational pesticide exposure in the Middle East. Future studies should adopt robust study designs, collect biological and environmental samples, conduct repeated sampling, analyze seasonal variations, and encompass diverse study sites associated with specific crop groups.

Agricultural pesticide exposure related to metabolic changes in Parkinson’s disease patients

Background: There are currently 13,543 pesticide products with 1059 active ingredients registered in California, potentially exposing residents of agricultural regions through drift and contamination. In order to comprehensively study agricultural pesticide exposure in a population-based study of Parkinson’s (PD), we determined networks of pesticide co-exposures due to living near agricultural applications (Central Valley, California). We estimated the risk of PD with patterns of co-exposure and assessed how PD-implicated co-exposures were related to the metabolome of patients in order to help understand biologic mechanisms and responses to exposure. Methods: We used lifetime participant address histories (n=1653), land-use maps, and the pesticide use reports database to estimate residential proximity-based exposure to 722 pesticides over a 40-year period. We applied an unsupervised, weighted pesticide co-exposure model based on WGCNA and exposure correlations to determine co-exposure modules, assessed influence on PD risk, and performed an exposure-related untargeted metabolome wide association study using LCMS data (5072 metabolites). Results: Our co-exposure model identified seven co-exposure modules based on 288 pesticides applied near the home of >25 participants. Of these, two were related to an increased risk of PD. Most strongly, one module representing co-exposures to 35 pesticides (OR=1.21 per SD, 95% CI=1.09, 1.38). Among the PD patients, this pesticide co-exposure module was related to differential intensity of 442 metabolites at p<0.05 (73 FDR<0.10, 10 FDR<0.05). This metabolite set was most strongly enriched for glycosphingolipid (p=0.002) and glycerophospholipid (p=0.003) metabolism pathways. Conclusions: Agriculturally, pesticides are rarely applied in isolation. We identified co-exposure modules related to PD risk. Among patients, the exposure mixture was strongly related to disturbances in biologic pathways relevant to PD pathogenesis (e.g., glycosphingolipids linked to inflammation and mitochondrial function in PD) and also known to be targeted by a number of pesticides (e.g., glycerophospholipids and choline/cholinergic pathways). Keywords: Pesticides; Metabolomics; Co-exposures; Parkinson’s disease

Potential Effects on Mental Health Status Associated with Occupational Exposure to Pesticides among Thai Farmers

Pesticide-related mental health issues in Thailand, an upper-middle-income country, are not well known. This study aimed to investigate the association between the history of occupational exposure to pesticides and the mental health of Thai farmers. A cross-sectional study was carried out in the areas around Chiang Mai, a large city in Northern Thailand, between June 2020 and January 2021. A total of 6974 farmers from six districts were interviewed to determine whether they regularly experienced symptoms related to mental health by the Self-Reporting Questionnaire (SRQ-20) as well as their lifetime history of agricultural pesticide exposure from 31 active ingredients and five functional categories: insecticides, herbicides, fungicides, rodenticides, and molluscicides. The cut-off of 6 was used to evaluate probable mental disorder. Most of the farmers under investigation were men (53.8%), with a mean age of 55.2 (11.7) years, and were involved mainly in the planting of rice, fruit, and vegetables. About 86.7% reported having used pesticides on their crops at some point in their lives—mostly glyphosate, paraquat, 2,4-D, methomyl, and carbofuran. All functional groups, as well as pesticide classes like organochlorines, organophosphates, and carbamates, were significantly associated with a higher risk of probable mental disorder based on exposure duration, frequency, personal protective equipment usage, and hygienic behavior. In a model with multiple pesticides, there was an association between mental disorder and exposure to endosulfan (AOR = 2.27, 95%CI = 1.26–4.08) and methyl parathion (AOR = 2.26, 95%CI = 1.26–4.06). Having previously reported pesticide poisoning symptoms was related to mental disorder (AOR = 7.97, 95%CI = 5.16–12.31), the findings provided evidence of pesticide exposure posing a risk to farmers’ mental health, particularly long-term and high-intensity exposure.

Potential propagation of agricultural pesticide exposure and effects to upstream sections in a biosphere reserve.

In the last decades, several studies have shown that pesticides frequently occur above water quality thresholds in small streams draining arable land and are associated with changes in invertebrate communities. However, we know little about the potential propagation of pesticide effects from agricultural stream sections to least impacted stream sections that can serve as refuge areas. We sampled invertebrates and pesticides along six small streams in south-west Germany. In each stream, the sampling was conducted at an agricultural site, at an upstream forest site (later considered as "refuge"), and at a transition zone between forest and agriculture (later considered as "edge"). Pesticide exposure was higher and the proportion of pesticide-sensitive species (SPEARpesticides) was lower in agricultural sites compared to edge and refuge sites. Notwithstanding, at some edge and refuge sites, which were considered as being least impacted, we estimated unexpected pesticide toxicity (sum toxic units) exceeding thresholds at which field studies suggested adverse effects on freshwater invertebrates. We conclude that organisms in forest sections within a few kilometres upstream of agricultural areas can be exposed to ecologically relevant pesticide levels. In addition, although not statistically significant, the abundance of pesticide-sensitive taxa was slightly lower in edge compared to refuge sites, indicating a potential influence of adjacent agriculture. Future studies should further investigate the influence of spatial relationships, such as the distance between refuge and agriculture, for the propagation of pesticide effects and focus on the underlying mechanisms.

Environmental pesticide exposure and non-Hodgkin lymphoma survival: a population-based study

BackgroundThere is evidence indicating that pesticide exposure is a risk factor for non-Hodgkin lymphoma (NHL) development. However, the association between pesticide exposure and NHL survival is not well-established.MethodsUsing the California Cancer Registry, we identified patients with a first primary diagnosis of NHL from 2010 to 2016 and linked these patients with CalEnviroScreen 3.0 to obtain production agriculture pesticide exposure to 70 chemicals from the state-mandated Pesticide Use Reporting (PUR) by census tract from 2012 to 2014. In addition, data from PUR was integrated into a geographic information system that employs land-use data to estimate cumulative exposure to specific pesticides previously associated with NHL (glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4-dimethylamine salt) between 10 years prior up to 1 year after NHL diagnosis. Multivariable Cox proportional hazards regression models were used to evaluate the association between total pesticide exposure from CalEnviroScreen 3.0 and individual pesticide exposure from geographic land use data and lymphoma-specific and overall survival.ResultsAmong 35,808 NHL patients identified, 44.2% were exposed to pesticide in their census tract of residence. Glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4-dimethylamine salt exposure was observed in 34.1%, 26.0%, 10.6%, 14.0%, and 12.8% of NHL patients, respectively. Total pesticide exposure at the time of diagnosis was not associated with lymphoma-specific or overall survival. In addition, no association was consistently found between glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4 dimethylamine salt exposure and lymphoma-specific or overall survival.ConclusionsAlthough we found no consistent associations between agricultural pesticide exposure at the neighborhood level and worse survival, these results provide a platform for designing future studies to determine the association between pesticide and NHL.

Effect of Pesticide Exposure on Non-Hodgkin Lymphoma Incidence and Survival in California

Introduction:While previous studies propose pesticide exposure to be a risk factor for non-Hodgkin lymphoma (NHL) development, results are inconclusive. In addition, the impact of pesticide exposure on NHL survival is not well-established. Therefore, we identified NHL patients from the California Cancer Registry and linked these patients with the statewide pesticide use reporting database to determine the impact of pesticide exposure on NHL-related incidence and outcomes.Methods:Using the California Cancer Registry, we identified patients with a first primary diagnosis of NHL from 2010-2016 and linked these patients with CalEnviroScreen 3.0 to obtain production agriculture pesticide exposure to 70 chemicals from the state mandated Pesticide Use Reporting (PUR) by census tract from 2012-2014. In addition, data from PUR was integrated into a geographic information system that employs land use data to estimate cumulative exposure to specific pesticides previously associated with NHL (glyphosate, organophosphorus, carbamate, phenoxyherbicide and 2,4-dimethylamine salt) between 10 years prior up to 1 year after NHL diagnosis. SEER*Stat software was used to calculate NHL subtype incidence rates by census tract pesticide use level. Multivariable cox proportional hazards regression models were used to evaluate the impact of total pesticide exposure from CalEnviroScreen 3.0 and individual pesticide exposure from geographic land use data on lymphoma-specific and overall survival.Results:Among 35,808 NHL patients identified, 44.2% were exposed to pesticide in their census tract of residence. Pesticide exposure was higher in Hispanic/Latino (46.5%) and non-Hispanic white (45.6%) then Asian/Pacific Islander (37.2%) and African American (34.9%) patients with NHL. Glyphosate, organophosphorus, carbamate, phenoxyherbicide and 2,4-dimethylamine salt exposure was reported in 34.1%, 26.0%, 10.6%, 14.0% and 12.8% of NHL patients, respectively. Pesticide exposure was not associated with increased NHL incidence by NHL subtype or subgroups defined by sociodemographic factors. Total pesticide exposure at time of diagnosis was not associated with lymphoma-specific or overall survival. In addition, no association was consistently found between glyphosate, organophosphorus, carbamate, phenoxyherbicide and 2,4 dimethylamine salt exposure and lymphoma-specific or overall survival.Conclusion:In this large population-based study of neighborhood agricultural pesticide exposure, pesticide exposure was noted to be prevalent among patients diagnosed with NHL, with high pesticide exposure particularly observed in Hispanics/Latinos and non-Hispanic whites. However, pesticide exposure was not consistently associated with increased NHL incidence or worse NHL lymphoma-specific or overall survival. DisclosuresPoh: Acrotech: Honoraria; Incyte: Research Funding; Morphosys: Consultancy. Tuscano: BMS: Research Funding; Seattle Genetics: Research Funding; Takeda: Research Funding; Acrotech: Research Funding; Genentech: Research Funding; Pharmacyclics: Research Funding; Abbvie: Research Funding.

Role of organophosphorous pesticides and acetylcholine in breast carcinogenesis.

Breast cancer is the leading cause of cancer-related death in women worldwide. Several studies have addressed the association between cancer in humans and agricultural pesticide exposure. Evidence indicates that exposure to organophosphorous pesticides such as parathion and malathion occurs as a result of occupational factors since they are extensively used to control insects. On the other hand, estrogens have been considered beneficial to the organism; however, epidemiological studies have pointed out an increased breast cancer risk in both humans and animals. Experimental female rat mammary gland cancer models were developed after exposure to parathion, malathion, eserine, an acetylcholinesterase inhibitor, and estrogen allowing the analysis of the signs of carcinogenicity as alteration of cell proliferation, receptor expression, genomic instability, and cell metabolism in vivo and in vitro. Thus, pesticides increased proliferative ducts followed by ductal carcinoma; and 17β-estradiol increased proliferative lobules followed by lobular carcinomas. The combination of both pesticides and either eserine or estrogen induced tumors with both types of structures followed by mammary gland tumors and metastasis to the lung and kidneys after 240 days of a 5-day treatment. Studies also showed that these pesticides and eserine decreased three to five times the acetylcholinesterase activity in the serum compared to controls whereas terminal end buds increased in number, being inhibited by atropine. Genomic instability was analyzed in such tissues (mp53, CYP1A2, c-myc, c-fos, ERα, M2R) and pesticides increased protein expression that was stimulated by estrogens but inhibited by atropine. Eserine also transformed the epithelium of the rat mammary gland in the presence of estrogen and increased the number of terminal end buds after treatment inducing mammary carcinomas. Then, enzymatic digestion of such structures gave rise to cells with increased DNA synthesis and induced anchorage independence. Thus, there were changes in the epithelium of the mammary gland influencing breast carcinogenesis. Furthermore, these substances and acetylcholine also showed the signs of carcinogenicity in vitro as cell proliferation, receptor expression (ERα, ErbB2, M2R), genomic instability (c-myc, mp53, ERα, M2R), and cell metabolism. A unique cellular model is also presented here based on the use of MCF-10 F, a non-tumorigenic cell line that represents a valuable clinically translatable experimental approach that identifies mechanistic links for pesticides and estrogen as suspect human carcinogenic agents.

Sublethal concentrations of clothianidin affect honey bee colony growth and hive CO2 concentration

The effects of agricultural pesticide exposure upon honey bee colonies is of increasing interest to beekeepers and researchers, and the impact of neonicotinoid pesticides in particular has come under intense scrutiny. To explore potential colony-level effects of a neonicotinoid pesticide at field-relevant concentrations, honey bee colonies were fed 5- and 20-ppb concentrations of clothianidin in sugar syrup while control colonies were fed unadulterated syrup. Two experiments were conducted in successive years at the same site in southern Arizona, and one in the high rainfall environment of Mississippi. Across all three experiments, adult bee masses were about 21% lower among colonies fed 20-ppb clothianidin than the untreated control group, but no effects of treatment on brood production were observed. Average daily hive weight losses per day in the 5-ppb clothianidin colonies were about 39% lower post-treatment than in the 20-ppb clothianidin colonies, indicating lower consumption and/or better foraging, but the dry weights of newly-emerged adult bees were on average 6–7% lower in the 5-ppb group compared to the other groups, suggesting a nutritional problem in the 5-ppb group. Internal hive CO2 concentration was higher on average in colonies fed 20-ppb clothianidin, which could have resulted from greater CO2 production and/or reduced ventilating activity. Hive temperature average and daily variability were not affected by clothianidin exposure but did differ significantly among trials. Clothianidin was found to be, like imidacloprid, highly stable in honey in the hive environment over several months.

The joint effect of ambient air pollution and agricultural pesticide exposures on lung function among children with asthma

BackgroundAmbient environmental pollutants have been shown to adversely affect respiratory health in susceptible populations. However, the role of simultaneous exposure to multiple diverse environmental pollutants is poorly understood. ObjectiveWe applied a multidomain, multipollutant approach to assess the association between pediatric lung function measures and selected ambient air pollutants and pesticides. MethodsUsing data from the US EPA and California Pesticide Use Registry, we reconstructed three months prior exposure to ambient air pollutants ((ozone (O3), nitrogen dioxide (NO2), particulate matter with a median aerodynamic diameter < 2.5 μm (PM2.5) and <10 μm (PM10)) and pesticides (organophosphates (OP), carbamates (C) and methyl bromide (MeBr)) for 153 children with mild intermittent or mild persistent asthma from the San Joaquin Valley of California, USA. We implemented Bayesian kernel machine regression (BKMR) to estimate the association between simultaneous exposures to air pollutants and pesticides and lung function measures (forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and forced expiratory flow between 25% and 75% of vital capacity (FEF25–75)). ResultsIn BKMR analysis, the overall effect of mixtures (pollutants and pesticides) was associated with reduced FEV1 and FVC, particularly when all the environmental exposures were above their 60th percentile. For example, the effect of the overall mixture at the 70th percentile (compared to the median) was a −0.12SD (−50 mL, 95% CI: −180 mL, 90 mL) change in the FEV1 and a −0.18SD (−90 mL, 95% CI: −240 mL, 60 mL) change in the FVC. However, 95% credible intervals around all of the joint effect estimates contained the null value. ConclusionAt this agricultural-urban interface, we observed results from multipollutant analyses, suggestive of adverse effects on some pediatric lung function measures following a cumulative increase in ambient air pollutants and agricultural pesticides. Given the uncertainty in effect estimates, this approach should be explored in larger studies.

Insecticides in agricultural streams exert pressure for adaptation but impair performance in Gammarus pulex at regulatory acceptable concentrations

Pesticide exposure in agricultural streams requires non-target species to adapt. However, pesticides may reduce performance in between exposure events due to long-term effects and physiological fitness costs of adaptation. Here, we investigated the long-term consequences of pesticide exposure to low concentrations in the widespread crustacean Gammarus pulex.We collected populations from six German streams covering no to moderate agricultural pesticide exposure. Peak concentrations ranged up to 1/400 of their acute median lethal concentration (Toxic Unit = −2.6), resulting in significant changes in the macroinvertebrate community composition (SPEARpesticides = up to 0.12). Acute toxicity tests revealed up to 2.5-fold increased tolerance towards the most frequently found insecticide clothianidin compared to populations from non-contaminated streams. However, populations showing increased insecticide tolerance were characterized by reduced survival, per capita growth and mating when cultured under pesticide-free conditions in the laboratory for three months.We conclude that pesticide pollution triggers adaptation both at the species and the community level even at concentrations considered to be safe according to the European pesticide legislation. In G. pulex, exposure and adaptation are associated with impaired performance which potentially affects ecosystem functions such as leaf litter degradation. These long-term impairments need to be considered in deriving safe concentrations.

Risk of Agricultural Pesticide Exposure to Malaria Incidence and Anopheles Susceptibility at an Endemic Area in Central Java, Indonesia – A Case–control Study

BACKGROUND: Malaria is an infectious disease caused by Plasmodium sp. This disease often occurs in tropical countries and has sometimes been reported in agricultural countries. This vector-borne disease is associated with environmental factors and the presence of vectors. Some studies found that Anopheles is resistant to insecticide, and this topic was encouraged by the WHO for malaria control.&#x0D; AIM: This research aimed to explain the causal effects of agricultural pesticide exposure on malaria incidence and Anopheles susceptibility in an endemic area of Indonesia.&#x0D; METHODS: A case–control study was conducted between September and October 2016 in Purworejo, Central Java. The case group involved 131 individuals who had malaria in 2016 based on their medical records, whereas the control group comprised 131 individuals who were neighbors of the cases and never had a history of malaria. Cases were selected randomly from hospital medical records. Both case and control groups were interviewed using the same questionnaire, and data were analyzed using logistic regression. Insecticide susceptibility test was used to test the 80 mosquito samples collected from the neighborhood of recent malaria cases.&#x0D; RESULTS: The quantity of agricultural pesticide remains a potential health risk to malaria (odds ratio = 2.15; 95% confidence interval 1.000–4.638), which was adjusted by confounders (sex, resting place, and insecticide net). The susceptibility test indicated that Anopheles was resistant to both permethrin (86.25%) and bendiocarb (68.75%).&#x0D; CONCLUSIONS: The quantity of agricultural pesticide contributes as a risk factor to malaria incidences, and Anopheles was indicated to be resistant to bendiocarb in Purworejo, Central Java.

The ARTEMIS Center: An Environmental Health Prevention Platform Dedicated to Reproduction.

In France, a new approach is being developed through the ARTEMIS Center, which is a prevention platform for environmental health dedicated to reproduction. The objective is to describe the clinical management of patients in the ARTEMIS center. Couples with a condition affecting reproduction are referred to the ARTEMIS center. Management includes a medical consultation and a standardized interview. Current exposure is assessed by a questionnaire that includes exposure circumstances to reproductive risk factor and on the basis of which it is possible to implement preventive action in clinical practice without prejudging the role of such exposure in the onset of disease. From 16 February 2016 to 2 May 2019, 779 patients were seen in the ARTEMIS center. On the day of the consultation, 88.3% men and 72.2% women were employed. Among employed men, 61.5% had at least one instance of occupational exposure to a reproductive risk factor, and among employed women, 57.8%. The main nonprofessional circumstances of exposure identified were proximity of the residence to an agricultural area (35.3%) and domestic pesticide exposure (79.7%). The preventive actions implemented by the ARTEMIS center are targeted to the individual practices of patients. However, patient care also allows their physicians to become familiarized with environmental health.

Agricultural Exposures and Breast Cancer Among Latina in the San Joaquin Valley of California.

The aim of this study was to assess the role of agricultural work, pesticide exposure, and age at first farm labor exposure in breast cancer (BC) risk among Hispanic women in Central California. A BC case control study was conducted. Latina BC cases were identified through the California Cancer Registry and controls were recruited. Both cases and controls completed a detailed questionnaire. Pesticide exposure data were obtained by linking the crops, work locations, and dates worked in specific farm jobs with the California Department of Pesticide Regulation (DPR) Pesticide Use Reports (PUR). Chemicals associated with BC risk included organophosphates, organochlorines, and a phthalimide, Captan. Age at first work in farm labor was younger in cases than controls (P = 0.03). Agricultural work may be associated with the increased BC risk in female Hispanic farm workers.

Residential agricultural pesticide exposures and risks of preeclampsia

We investigated risks of preeclampsia phenotypes from potential residential pesticide exposures, including 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998–2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. The following numbers of women with preeclampsia phenotypes were identified: 1045 with superimposed (pre-existing hypertension with preeclampsia) preeclampsia (265 with gestational weeks 20–31 and 780 with gestational weeks 32–36); 3471 with severe preeclampsia (824 with gestational weeks 20–31 and 2647 with gestational weeks 32–36); and 2780 with mild preeclampsia (207 with gestational weeks 20–31 and 2573 with gestational weeks 32–36). The reference population for these groups was 197,461 women who did not have diabetes (gestational or pre-existing), did not have any hypertensive disorder, and who delivered at 37 weeks or later. The frequency of any exposure was lower or about the same in each preeclampsia case group (further delineated by gestational age), and month time period, relative to the frequency in reference population controls. Nearly all odds ratios were below 1.0 for these any vs no exposure comparisons. This study showed a general lack of increased risks between a range of agriculture pesticide exposures near women's residences and various preeclampsia phenotypes.

Residential Agricultural Pesticide Exposures and Risks of Spontaneous Preterm Birth

Pesticides exposures are aspects of the human exposome that have not been sufficiently studied for their contribution to risk for preterm birth. We investigated risks of spontaneous preterm birth from potential residential exposures to 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. After exclusions, the analytic study base included 197,461 term control births and 27,913 preterm case births. Preterm cases were more narrowly defined as 20-23 weeks (n = 515), 24-27 weeks (n = 1,792), 28-31 weeks (n = 3,098), or 32-36 weeks (n = 22,508). The frequency of any (versus none) pesticide exposure was uniformly lower in each preterm case group relative to the frequency in term controls, irrespective of gestational month of exposure. All odds ratios were below 1.0 for these any versus no exposure comparisons. The majority of odds ratios were below 1.0, many of them statistically precise, for preterm birth and exposures to specific chemical groups or chemicals. This study showed a general lack of increased risk of preterm birth associated with a range of agriculture pesticide exposures near women's residences.

Combined Prenatal Pesticide Exposure and Folic Acid Intake in Relation to Autism Spectrum Disorder.

Background:Maternal folic acid (FA) protects against developmental toxicity from certain environmental chemicals.Objective:We examined combined exposures to maternal FA and pesticides in relation to autism spectrum disorder (ASD).Methods:Participants were California children born from 2000–2007 who were enrolled in the Childhood Autism Risks from Genetics and the Environment (CHARGE) case–control study at age 2–5 y, were clinically confirmed to have ASD () or typical development (), and had information on maternal supplemental FA and pesticide exposures. Maternal supplemental FA and household pesticide product use were retrospectively collected in telephone interviews from 2003–2011. High vs. low daily FA intake was dichotomized at (median). Mothers’ addresses were linked to a statewide database of commercial applications to estimate agricultural pesticide exposure.Results:High FA intake () during the first pregnancy month and no known pesticide exposure was the reference group for all analyses. Compared with this group, ASD was increased in association with and any indoor pesticide exposure {adjusted odds ratio [95% confidence interval (CI): 1.3, 4.7]} compared with low FA [ (95% CI: 0.7, 2.2)] or indoor pesticides [ (95% CI: 1.1, 2.8)] alone. ORs for the combination of low FA and regular pregnancy exposure () to pet pesticides or to outdoor sprays and foggers were 3.9 (95% CI: 1.4, 11.5) and 4.1 (95% CI: 1.7, 10.1), respectively. ORs for low maternal FA and agricultural pesticide exposure 3 mo before or after conception were 2.2 (95% CI: 0.7, 6.5) for chlorpyrifos, 2.3 (95% CI: 0.98, 5.3) for organophosphates, 2.1 (95% CI: 0.9, 4.8) for pyrethroids, and 1.5 (95% CI: 0.5, 4.8) for carbamates. Except for carbamates, these ORs were approximately two times greater than those for either exposure alone or for the expected ORs for combined exposures under multiplicative or additive models.Conclusions:In this study population, associations between pesticide exposures and ASD were attenuated among those with high versus low FA intake during the first month of pregnancy. Confirmatory and mechanistic studies are needed. https://doi.org/10.1289/EHP604

Agricultural pesticide use and adverse birth outcomes in the San Joaquin Valley of California

Virtually all agricultural communities worldwide are exposed to agricultural pesticides. Yet, the health consequences of such exposure are poorly understood, and the scientific literature remains ambiguous. Using individual birth and demographic characteristics for over 500 000 birth observations between 1997–2011 in the agriculturally dominated San Joaquin Valley, California, we statistically investigate if residential agricultural pesticide exposure during gestation, by trimester, and by toxicity influences birth weight, gestational length, or birth abnormalities. Overall, our analysis indicates that agricultural pesticide exposure increases adverse birth outcomes by 5–9%, but only among the population exposed to very high quantities of pesticides (e.g., top 5th percentile, i.e., ~4200 kg applied over gestation). Thus, policies and interventions targeting the extreme right tail of the pesticide distribution near human habitation could largely eliminate the adverse birth outcomes associated with agricultural pesticide exposure documented in this study.