ORIGINAL ABSTRACT

Although evidence of adverse effects on human health is still scarce, exposure to pesticides has been shown to have a negative impact outside agroecosystems. We compared exposure to current use pesticides in one area surrounded by crop fields (Area 1) with exposure in another area located in the center of a city (Area 2). Both areas are located within one of the world's most agriculturally productive regions. We analyzed the presence of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) in urine samples from 86 female volunteers who had been environmentally exposed. Potential genotoxicity was tested using the micronucleus assay on buccal mucosa samples taken from the same donors. We also evaluated the residues of current use pesticides in drinking water and soil samples taken from public places in the two areas. All the analytical determinations were performed using ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS/MS). When glyphosate-positive samples were considered, significantly higher concentrations of glyphosate were found in Area 1 than in Area 2 (p = 0.02). An increase in the frequency of binucleated cells (p = 0.039) and linked nucleus (p = 0.035) was observed in women from Area 1 compared to those from Area 2. All the drinking water samples tested positive for at least two pesticide residues while 85% of the soil samples tested positive for at least 1. A total of 27 different pesticides were detected in the drinking water in Area 1, with detection frequencies ranging from 5 to 79%. In Area 2, imidacloprid, 2,4-D, atrazine and dichlosulam were detected at detection frequencies of 100%, 71%, 57% and 29%, respectively. In soils from Area 1, the metabolites hydroxy atrazine and AMPA presented the higher detection frequency, while in Area 2, glyphosate and AMPA were detected in 71% of samples, followed by atrazine and its metabolites. Modelling showed that the distance between donors' homes and crop fields was the key factor in explaining glyphosate and AMPA concentrations in urine, the presence of pesticides in drinking water and the observed cytotoxicity. The significant cytotoxicity detected in women living near crop fields is a particular cause for concern regarding potential hazards to human health in that area. On the other hand, this study has also demonstrated the ubiquity of the current use pesticides in environmentally exposed women, since glyphosate has been found in the urine of people living in urban areas. This fact merits further, more in-depth analysis.