Preliminary risk assessment database and risk ranking of pharmaceuticals in the environment.
There is increasing concern about pharmaceuticals entering surface waters and the impacts these compounds may have on aquatic organisms. Many contaminants, including pharmaceuticals, are not completely removed by wastewater treatment. Discharge of effluent into surface waters results in chronic low-concentration exposure of aquatic organisms to these compounds, with unknown impacts. Exposure of virulent bacteria in wastewater to antibiotic residues may also induce resistance, which could threaten human health. The purpose of this study was to provide information on pharmaceutical threats to the environment. A preliminary risk assessment database for common pharmaceuticals was created and put into a web-accessible database named "Pharmaceuticals in the Environment, Information for Assessing Risk" (PEIAR) to help others evaluate potential risks of pharmaceutical contaminants in the environment. Information from PEIAR was used to prioritize compounds that may threaten the environment, with a focus on marine and estuarine environments. The pharmaceuticals were ranked using five different combinations of physical-chemical and toxicological data, which emphasized different risks. The results of the ranking methods differed in the compounds identified as high risk; however, drugs from the central nervous system, cardiovascular, and anti-infective classes were heavily represented within the top 100 drugs in all rankings. Anti-infectives may pose the greatest overall risk based upon our results using a combination of factors that measure environmental transport, fate, and aquatic toxicity. The dataset is also useful for highlighting information that is still needed to assuredly assess risk.