64.4 Sunday, Jan. 6 Comparing toxicological effects of Triclosan on multiple taxa: Washing away our natural communities WILSON, BA; University of Massachusetts, Boston email@example.com
Pharmaceutical and personal-care products (PPCPs) and their degradation products are introduced into the environment with waste-water discharge from sewage treatment facilities as the primary source. Their release into surface waters can cause unintended and detrimental affects on resident aquatic organisms as well as reduce the functioning of critical and economically important components of these ecosystems. Triclosan, like many PPCPs, partitions in estuaries between aqueous and particulate bound phases. Its bioavailability and toxicity in both phases will help to determine where mitigation needs to be placed in order to protect natural communities. This study looked at the acute toxicity of Triclosan on the natural algal community fluorescence (0-96 h) and its toxicity to bacterium using Microtox techniques (<1h). The suspended algal community shows a greater loss in overall productivity when exposed for at least 24h intervals to environmentally relevant concentrations of Triclosan. In contrast, Microtox testing shows almost no effect on the test bacterium productivity, when exposed to contaminated sediments or aqueous Triclosan. This comparative-method demonstrates that the aqueous form of Triclosan is either more toxic or more readily available than the bound form, to micro-organisms. By comparing the effects on multiple taxa we will be better able to understand where to focus management efforts.