Pesticide exposure as prenatal exposome: A biomonitoring study in pregnant women from Argentina.

Environmental exposure to pesticides may alter the prenatal exposome affecting maternal health and fetal development. This study investigated the presence of pesticides in urine samples from pregnant women residing in the center-northern region of Santa Fe, Argentina, characterized by intensive agricultural and horticultural activities. Additional analyses examined the relationship between rural and urban populations in terms of sociodemographic factors, pregnancy-related complications, and the frequency of urinary pesticides detection. A multicenter cross-sectional study was conducted, including 89 pregnant women from rural (n = 51) and urban (n = 38) regions. A total of 74 pesticides were analyzed in single spot urine samples using gas chromatography-tandem mass spectrometry (GC-MS/MS). A descriptive analysis of the population was carried out using biomonitoring, sociodemographic, lifestyle, and pregnancy outcomes. Pesticide residues were detected in 80.9 % of the samples, with a total of 39/74 compounds identified. Furthermore, 64 % of the samples had multiple residues (median: 2.0, range: 2-15). The most frequently detected compounds were vinclozolin fungicide (44.9 %, 0.1-3.6 μg L), propazine herbicide (22.5 %, 0.1-0.2 μg L) and triazophos insecticide (19.1 %, 0.6-12.0 μg L). The pattern of detection and the number of urinary pesticides (median: 2.0) were comparable between rural and urban participants. Also, sociodemographic and lifestyle factors did not differ between both populations. However, rural participants showed an increased prevalence of pregnancy-related complications (49 % vs 19 %, p=0.013). Regarding pesticide exposure and pregnancy outcomes, both the number of urinary residues (median: 4, p=0.02) and the detection of triazole fungicides (p=0.022) were significantly higher in pregnancies complicated by intrauterine growth restriction. Our findings suggest that intense pesticide use in Argentina may contribute to environmental exposure and exposome imbalances in a vulnerable population. The increased prevalence of pregnancy-related complications among rural participants highlights the need for a comprehensive review of pesticide use protocols, exposure limits and health risk assessments in agriculture and horticulture programs.