Baltimore Ecosystem Study Cary Institute of Ecosystem Studies

2012 BES Annual Meeting Presentation and Poster Abstracts



 
Ecological effects of common pharmaceutical compounds in BES streams
 
Rosi-Marshall, Emma
Co-Authors: Heather Bechtold, Miguel Rojas, John Kelly and Todd Royer

 
Abstract: Pharmaceutical and personal care products (PPCPs) are ubiquitous in surface waters throughout the world but their effects on ecological function and structure are not well understood. We measured in situ responses of stream biofilms to six common pharmaceutical compounds (caffeine, cimetidine, ciprofloxacin, diphenhydramine, metformin, ranitidine and a mixture of each) by deploying pharmaceutical diffusing substrates along a gradient of increasing urban cover, in Gwynns Falls at Gywnnbrook, Dead Run, Gwynns Run and Carroll Park. We observed that the effects of caffeine, ciprofloxacin, cimetidine and diphenhydramine on microbial respiration were site dependent, with low intensity urban sites displaying a greater response to PPCP exposure. In contrast, primary production was suppressed (nearly 99%) by diphenhydramine at all sites, regardless of extent of urbanization in the watershed. In Dead Run, we measured the response of the composition of bacterial communities to caffeine and diphenhydramine using 16S rRNA pyrosequencing. Although caffeine suppressed microbial respiration, there were no changes in the bacterial species composition. In contrast, diphenhydramine significantly suppressed respiration and altered the bacterial species present. These common PPCPs, alone or in combination, influenced stream biofilm communities and could have consequences for higher trophic levels and important ecosystem functions such as nutrient and organic matter processing.