A TALE OF TWO CULTURES: EMERGING PHARMACEUTICALS AND PERSONAL CARE PRODUCTS IN FRESH WATER

Pharmaceutical and personal care products (PPCPs) have been recognized as an important group of contaminants because of their frequent occurrence and ecological risks such as endocrine disrupting potential. PPCPs enter the environment from wastewater, but unlike legacy organic contaminants (persistent organic pollutants), most PPCPs are not currently regulated. Hundreds of PPCP compounds and their metabolites have been detected in rivers, lakes, groundwater, and even tap water worldwide. PPCPs from several classes are frequently detected including antibiotics (sulfonamides, macrolides, and fluroquinolones), antiseptics (triclosan and triclocarban), painkillers (acetaminophen and ibuprofen), antiepileptics drugs (carbamazepine), lipid regulators (clofibric acid), beta blockers (metoprolol and atenolol), and estrogens (estrone). Concentrations of PPCPs in freshwater were generally at ng/L levels, but some PPCPs such as ciprofloxacin have been detected at mg/L in rivers and reservoirs that are heavily impacted by wastewater.

Occurrence and concentrations of PPCP in freshwater are generally closely related to their usage and local wastewater treatment, and consequently vary depending on the region. For instance, the painkiller naproxen was frequently detected in rivers of the U.S., Canada, and Europe but not in those of China. Median concentrations of the most frequently detected antibiotics in rivers and lakes of western countries were dehydroerythromycin (100 ng/L), sulfamethoxazole (150 ng/L), and trimethoprim (150 ng/L). A different suite of antibiotics were ubiquitous in river water samples of China, with median concentrations of sulfamethazine (314 ng/L), sulfamethoxazole (100 ng/L), trimethoprim (38 ng/L), dehydroerythromycin (76 ng/L), and roxithromycin (33 ng/L). X-ray contrast agents (iopromide)were also widely detected in waters of China, whereas antidepressants (fluoxetine) were more frequently detected in the U.S. and Canada.

PPCPs in the freshwater environment, especially antibiotics, hormones, and xeno-hormones may be toxic to aquatic organisms at concentrations that have been detected in the water environment; therefore, additional research on the occurrence and toxicity of these compounds is critical to public health.