Publication Date
4-7-2007
Abstract
Pharmaceuticals and personal care products (PPCPs) may be introduced to the environment via household disposal through plumbing drains, followed by conveyance to municipal wastewater treatment plants (WWTPs). PPCP residuals contained in WWTP effluent may be discharged to aquatic systems (e.g., rivers, lakes, estuaries), while PPCP residuals in sludge may enter the terrestrial system through land application of sludge-derived biosolids. Rarely are the potential effects of those PPCP residuals on aquatic and terrestrial species considered. An ecological risk assessment framework was therefore developed to allow the quantitative evaluation of potential ecological risks posed by PPCPs in WWTP effluent and land-applied biosolids. In this framework, a fugacity and bioaccumulation model is employed to estimate distributions of potential ecological exposure under various environmental conditions. The predicted exposure estimates are then compared to measured or estimated effects concentrations for each ecological species of interest, in order to calculate potential risk from aquatic or terrestrial exposures. Additionally, the estimated dietary doses to mammalian and avian species can be compared to toxicity reference values derived from the primary or proprietary literature in order to determine risk from food chain exposures.