Recent and ever exposure predictors of urinary pesticide biomarkers among children in South Africa: A two - year longitudinal study.

Residential pesticide exposure, mortality risk, and the potential mediating role of urinary metabolites: evidence from a nationally representative cohort

Probabilistic Risk Assessment and Integrated Statistical Modelling to Identify the Key Factors in Acute and Chronic Arsenic Toxicity Among Schoolchildren for Proactive Toxicity Management

The need for integrated mitigation strategies that address both environmental exposure and nutritional vulnerability to reduce the health impacts of As among primary schoolchildren from As-affected and apparently control areas is highlighted.

A Multi-Pathway Approach to Pesticide Exposure in Agricultural Communities: Protocol for an Observational Study.

BACKGROUND The widespread use of pesticides in agriculture raises concerns about exposure among populations living near treated fields. Environmental contamination may lead to prolonged pesticide exposure, with potential health effects, yet significant knowledge gaps remain regarding exposure levels and pathways in agricultural communities. OBJECTIVE The Exposure to Pesticides Used in Regions of Agriculture (EPURA) study aims to characterize pesticide exposure patterns and identify their key sources and determinants through an integrated approach combining biological and environmental measurements. METHODS We recruited 400 participants from agricultural communities living within 1500 meters of vegetable production fields in Quebec, Canada, throughout the 2 years of data collection. Over 4 summer months and 3 winter months, participants provided monthly urine samples and floor wipes and completed questionnaires on diet, water consumption, household characteristics, pesticide use, and lifestyles. Summer and winter urine samples were pooled for each participant, and summer and winter wipe samples were pooled for each household. At the end of the summer, we collected additional samples, including indoor dust, yard soil, and tap water. Environmental and biological samples will be analyzed for 51 pesticides and their metabolites. Pesticide applications near residences will be estimated using agricultural land use data integrated into a geographic information system. Pesticide intake from food and water will be assessed by combining consumption data with pesticide residues measured in water and in food monitoring programs. Residential contamination will be estimated by measuring pesticides in indoor dust and yard soil. Urinary pesticide concentrations will be used to estimate exposure doses. Urinary concentrations will be compared across population subgroups and seasons and with available Canadian biomonitoring data. Associations between exposure doses and dietary and water intake, indoor and outdoor contamination, proximity to treated fields, and household-level determinants will be examined using mixed models. Variable selection will be performed using high-dimensional methods. RESULTS As of June 1, 2026, participant recruitment and data collection are complete. A total of 173 households (372 participants) were included in the study, with 1049 wipe samples, 170 sealed petri dishes, 157 water samples, 170 yard soil samples, and 2257 urine samples collected. Completion of all laboratory analyses is expected in 2027, after which the statistical analyses will be conducted in accordance with the study objectives. CONCLUSIONS This study will generate crucial data on pesticide exposure in agricultural communities. Its findings will help identify major determinants of household contamination and key risk factors contributing to residents' pesticide exposure. Ultimately, the EPURA study will support the development of targeted strategies to reduce pesticide-related health risks and inform public health policies. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/94740.

Maternal exposure to pyrethroid insecticides during pregnancy and repeated measures of infection symptoms among early school-aged children in the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE).

OBJECTIVE Indoor residual spraying (IRS) using pyrethroids insecticides to control malaria results in high exposure to local populations. Pyrethroids are immunosuppressant and prenatal exposure has been associated with higher rates of infection-related symptoms such as fever and colds among preschool children. Whether associations persist at older ages is unclear. Furthermore, prior studies assessed symptoms based on recall periods of ≥1 year, which may introduce misclassification. The aim of this study was thus to estimate associations between prenatal exposure to pyrethroids and infections among early school-aged children from an IRS area using shorter recall periods. METHODS We measured urinary concentrations of four pyrethroid metabolites in peripartum samples collected from mothers enrolled in the Venda Health Examination of Mothers, Babies, and their Environment (VHEMBE), a birth cohort study situated in Limpopo, South Africa, where IRS with pyrethroids is conducted annually. From age 5, we collected data on infection symptoms using up to 4 questionnaires each encompassing a three-month recall period. We used Poisson marginal structural models for repeated outcomes to estimate associations between maternal exposure to pyrethroids and infection symptoms. RESULTS A 10-fold increase in maternal cis-DCCA, trans-DCCA and 3-PBA was associated with a doubling in the rates of persistent fever (cis-DCCA: Incidence Rate Ratio [IRR] = 1.9, 95% CI = 1.2, 3.2; trans-DCCA: IRR = 2.2, 95% CI = 1.4, 3.5; 3-PBA: IRR = 1.9, 95% CI = 1.0, 3.4). Higher trans-DCCA was also related to a 70% increase in diarrhea rates (IRR = 1.7, 95% CI = 1.0, 2.8). CONCLUSION Maternal pyrethroid exposure may be related to elevated infection rates among early school-aged children from an IRS area. In addition to IRS, pyrethroids are widely used in agriculture and retail products. Results may thus have global implications.

Serum NO₃⁻ and NO₂⁻ levels among pregnant women from agricultural communities: associations with self-reported dietary and environmental exposures.

Nitrate (NO₃⁻) and nitrite (NO₂⁻) exposure can lead to adverse health impacts, yet data on direct biomarkers are limited. To assess serum NO₃⁻ and NO₂⁻ levels among pregnant women in two agricultural regions of the Jordan Valley in relation to dietary and environmental factors. This cross-sectional study recruited 346 pregnant women aged 18 years or older from four hospitals in the Ghor region between 2023 and 2024. Serum NO₃⁻ and NO₂⁻ levels were measured using a Griess assay. Socio-demographic data, dietary habits, and water source information were gathered through questionnaires. The median serum NO₂⁻ level was 0.63 µM and the median serum NO₃⁻ level was 19.13 µM in the overall sample. Serum NO₂⁻ was significantly higher among women from North Ghor compared to South Ghor (0.83 µM vs. 0.45 µM, p < 0.001), while serum NO₃⁻ levels did not significantly differ between regions. In multivariable models adjusting for maternal age, BMI, hypertension, anemia, and smoking, we found that variables of region of residency and eating green beans once a week or more were significantly associated with higher NO₂⁻ levels in the whole sample (p < 0.001 and p = 0.031, respectively) and in North Ghor (p = 0.032), while hypertension was associated with lower NO₂⁻ levels (p = 0.032 whole sample; p = 0.013 North Ghor). For NO₃⁻, smoking during pregnancy was associated with lower levels in the whole sample (p = 0.003) and in South Ghor (p = 0.004), while employment in crop harvesting/collection was associated with higher NO₃⁻ levels in South Ghor (p = 0.024). Regional differences in serum NO₂⁻ levels exist among pregnant women in rural Jordan, influenced primarily by dietary habits, while occupational exposure to crop harvesting and smoking were associated with serum NO₃⁻ levels. Targeted recommendations and public health strategies are needed to mitigate NO₃⁻ and NO₂⁻ exposure.

Environmental and Household Sources Associated with Elevated Blood Lead Levels Among Mexican Women of Childbearing Age: A Community-Based Screening Study

Background: Lead (Pb) exposure remains a significant public health concern, particularly among women of childbearing age, because of its adverse effects on maternal–child health. Although lead-glazed ceramics (LGC) for cooking or storing food are a well-recognized source of Pb exposure in Mexico, other environmental and household sources remain insufficiently characterized. Objective: To identify environmental and household factors associated with elevated blood lead levels (BLLs) among women of childbearing age participating in a community-based screening in Mexico City. Methods: We conducted a cross-sectional analysis of 158 women aged 18–40 years. Capillary BLLs were measured using the LeadCare® II system. Participants completed a structured questionnaire assessing potential Pb sources of exposure. Elevated BLL was defined as ≥3.5 µg/dL. Associations between exposure sources and elevated BLL were evaluated using multivariable logistic regression adjusted for sociodemographic and lifestyle factors. Shapley decomposition was used to estimate the relative contribution of each exposure source to the model. Results: The prevalence of elevated BLLs was 31%. Women reporting both past and current use of LGC had higher odds of elevated BLLs than women who had never used LGC (adjusted OR = 9.43; 95% CI: 1.85–48.15). Living in or regularly visiting a recently remodeled home (adjusted OR = 3.21; 95% CI: 1.45–7.11) and living near a highway (adjusted OR = 2.41; 95% CI: 1.07–5.48) were also independently associated with elevated BLLs. LGC use was the largest contributor to the model performance (47.46%), followed by home remodeling (31.78%) and proximity to highways (20.76%). Conclusions: Our findings support LGC as an important source of Pb exposure while identify home remodeling and residential proximity to highways as additional sources associated with elevated BLLs. Together, these findings broaden the understanding of Pb exposure pathways among women of childbearing age and support the need for prevention and screening strategies.