Analytical methods for detection of selected estrogenic compounds in aqueous mixtures

Both natural estrogens and synthetic compounds that mimic estrogen can reach the aquatic environment through wastewater discharges. Because nonylphenol (NP), octylphenol (OP), nonylphenol polyethoxylates (NPE), 17β- estradiol (E2), and ethynylestradiol (EE2) have previously been found to be estrogenic and to occur in wastewater effluents, they were the primary analytes for which the method was developed. Water samples were extracted in situ using solid-phase extraction disks. Analytes were separated by high- pressure liquid chromatography and detected by fluorescence or competitive radioimmunoassay (RIA). Method detection limits (MDLs) using HPLC with fluorescence detection were 11, 2, and 52 ng/L of water for NP, OP, and NPE, respectively. The RIA MDLs for E2 and EE2 were 107 and 53 pg/L, respectively. Samples were collected from four municipal wastewater treatment plants in south central Michigan, eight locations on the Trenton Channel of the Detroit River, MI, and five locations in Lake Mead, NV. Concentrations of NP and OP ranged from less than the MDL to 37 and 0.7 μg/L, respectively. NPE concentrations ranged from less than the MDL to 332 μg/L. Concentrations of E2 and EE2 ranged from less than the MDLs to 3.7 and 0.8 ng/L, respectively.