Assessing selected estrogens and xenoestrogens in Brazilian surface waters by liquid chromatography–tandem mass spectrometry

A sensitive and specific method was developed and validated for the determination of estrogen and xenoestrogen in surface waters using liquid chromatography followed by tandem mass spectrometry. Chromatographic separation was performed using ammonium hydroxide solutions in water and in methanol as mobile phase. Compounds were determined in a triple quadrupole mass spectrometer equipped with an electrospray ionization interface operating in the negative mode. Multiple reaction monitoring conditions were optimized for estrone, 17β-estradiol, estriol, 17α-ethinylestradiol, bisphenol A, 4-n-octylphenol, and 4-n-nonylphenol. The method was linear from 0.1 ng L− 1 to 10 µgL− 1. Limits of quantification varied between 0.1 and 3.1 ng L− 1 and recoveries for a 50 ng L− 1 spiked-surface water solution varied between 72 and 140%. The method was successfully used to determine estrogen and xenoestrogen levels in Brazilian water samples collected along the Atibaia River Basin, in the State of São Paulo. Concentrations of estrogens varied from 2.2 to 39 ng L− 1. Bisphenol A was the most frequently detected compound as well as the only xenoestrogen in the samples with concentrations between 25 and 84 ng L− 1.