Chlorination and Photolysis of Pharmaceutical and Personal Care Product (PPCP) PollutantsEPA Grant Number: F6B20740
Title: Chlorination and Photolysis of Pharmaceutical and Personal Care Product (PPCP) Pollutants
Investigators: Buth, Jeffrey M.
Institution: University of Minnesota
EPA Project Officer: Carleton, James N
Project Period: September 1, 2006 through September 1, 2009
Project Amount: $111,172
RFA: STAR Graduate Fellowships (2006) RFA Text | Recipients Lists
Research Category: Fellowship - Chemistry , Academic Fellowships , Aquatic Ecosystems
Recently, concern has grown regarding the presence of pharmaceutical and personal care product (PPCP) pollutants in aquatic systems. It is likely that many will undergo reactions with free chlorine during disinfection in water treatment or photo-degradation in surface waters, yielding products that may retain or acquire elevated levels of biological activity/toxicity. Triclosan, a common anti-microbial agent, was chosen as a target PPCP to study since it has been shown to chlorinate under wastewater disinfection conditions and to photolyze to form toxic 2,8-dibenzodioxin upon irradiation (Rule et al., 2005; Latch et al., 2005).
One aim is to investigate the photochemistry of chlorinated triclosan derivatives (CTDs) to determine whether toxic chlorinated dioxins are generated. Another goal is to determine if CTDs are produced from triclosan during disinfection with free chlorine and if chlorinated dioxins subsequently form upon irradiation at a detectable level in the environment.
CTDs will be synthesized by reacting triclosan with free chlorine. Aqueous photolysis rates of CTDs will be measured, and photo-products will be identified. An environmental monitoring program will be carried out to measure concentrations of triclosan, CTDs, and chlorinated dioxins in wastewater, effluent, and receiving river water.
It is expected that CTDs will form from triclosan during disinfection of wastewater and enter the receiving river with wastewater treatment plant effluent. CTDs are then expected to undergo photo-induced ring-closure to form chlorinated dioxins, introducing these toxic compounds to the aquatic ecosystem.