In this study, a multi-residue method was used to analyze 13 pesticides and 1 degradation product in surface and groundwater in the region with the largest sugar cane production in the world. The potential effects of individual pesticides and their mixtures, for aquatic life and human consumption, were evaluated. For the surface water, 2-hydroxy atrazine, diuron, carbendazim, tebuthiuron, and hexazinone were the most frequently detected (100, 94, 93, 92, and 91%, respectively). Imidacloprid (2579 ng L-1), carbendazim (1114 ng L-1), ametryn (1101 ng L-1), and tebuthiuron (1080 ng L-1) were found at the highest concentrations. For groundwater, tebuthiuron was the only quantified pesticide (107 ng L-1). Ametryn, atrazine, diuron, hexazinone, carbofuran, imidacloprid, malathion, carbendazim, and their mixtures presented risk for the aquatic life. No risk was observed for the pesticides analyzed in this work, alone or in their mixtures for human consumption.
Keywords: Groundwater; Human consumption; Mixture toxicity; PCA; Risk assessment; Surface water.