Determination of 17α-ethinylestradiol and toxic metals in surface waters, and estimation of daily intake

The presence of substances such as hormones and toxic metal in aquatic ecosystem is interesting to the scientific community due to their adverse effects. We quantified 17α-ethynylestradiol (EE2) and toxic metals in the surface waters from Sorocaba and Pirajibu Rivers, in São Paulo State, and we estimated the daily intake for hormone, based on the amount of water consumed. EE2, Cd, Hg, As, Pb, and Mn were seasonally quantified in six different locations along the rivers. EE2 was evaluated by high-performance liquid chromatography. Toxic metals were determined by inductively coupled plasma mass spectrometer. Considering the entire sample year, EE2 concentrations ranged from 4.5 to 48.2 μg L⁻¹. Comparing Sorocaba and Pirajibu rivers, the sample point in the entrance of the Pirajibu River through the city of Itu, São Paulo State, had higher amounts of EE2. Regarding metals, all results are according to the Brazilian and World Health Organization guidelines for drinking-water quality, except for Mn levels, which were higher than the limits in Autumn season in two locations. The estimated daily intake ranged from 13.45 to 40.9 μg/day/person. In conclusion, concentrations of EE2 in the Sorocaba and Pirajibu Rivers were higher than in other countries. The levels were as high as an intake of one pill for each person every day (considering an oral contraceptive has 0.03 mg of ethinylestradiol). Even though concentrations of toxic elements are in accordance with the Brazilian Regulation and World Health Organization, legislation for hormones and drugs needs to advance.