Contamination of Maine lakes by pharmaceuticals and personal care products

Pharmaceuticals and personal care product chemicals (PPCPs) are known to contaminate surface waters, especially rivers and streams downstream of wastewater treatment plants. However, their presence in lakes is not as well understood, as they are not commonly monitored during traditional water quality assessments of lakes. The primary goal of this study was to determine PPCP contamination in the Belgrade Lakes, an inland lakes chain in central Maine, USA. Samples were collected from 30 sites on four lakes and two streams and analyzed using LC-MS. We detected six PPCPs in the four lakes (listed in decreasing order of frequency): amphetamine, caffeine, 1,7-dimethylxanthine, sulfachloropyridazine, acetaminophen, and cotinine. Most sampling sites had at least one PPCP detected, but importantly, nearly all concentrations were only slightly above the limits of detection. The number of PPCP detections at public high use sites was higher than at private sites. These results indicate that the Belgrade Lakes are not highly contaminated by PPCPs, and even though PPCP sources were not identified, the main source of contamination may be direct human contact with and use of the lakes. There is no wastewater treatment plant in this lakes chain, and a survey of property owners did not reveal widespread problems with septic system maintenance. Despite low PPCP concentrations, there may be ecological and human health effects from long-term exposure, so further research on PPCP impacts at environmentally relevant levels is warranted.