Occurrence of pharmaceuticals and personal care products along the West Prong Little Pigeon River in east Tennessee, USA

Presence of pharmaceuticals and personal care products (PPCPs) in the environment has received a great attention due to their potential impacts on public health. This study examined the occurrence of PPCPs in West Prong Little Pigeon River in east Tennessee. As wastewater is a major source for environmental occurrence of PPCPs, both wastewater and river water samples were analyzed for nine target PPCPs and their estrogenicity. No estrogens were detected in influent, secondary effluent, and river samples. However, ibuprofen, caffeine, triclosan, bisphenol A, and bis(2-ethylhexyl)phthalate (DEHP) were detected in the influent. Ibuprofen, triclosan, and DEHP were detected in the secondary effluent samples. Only ibuprofen and triclosan were detected in river water collected near a wastewater outfall. Based on yeast estrogenic screening (YES) assays, estrogenic activities were observed in all influent, secondary effluent, and river water samples. Increased estrogenic activities were observed in river right after receiving effluent discharge, and the activities decreased as river water flowing away from the outfall. The estrogenicities of water samples measured from YES assays were much higher than those estimated from PPCP concentrations and their known estrogenicities, suggesting the presence of other unknown estrogenic compounds and/or additive effects of mixtures of estrogenic compounds at low concentrations. Results of this study demonstrated that wastewater contributed to environmental occurrence of PPCPs in the receiving water. As there is a myriad of known and unknown PPCPs in wastewater, in additional to chemical analysis, estrogenic bioassays are needed for assessing estrogenicity of environmental samples.