You are here:
Prioritizing pharmaceuticals in municipal wastewater
Citation:
KOSTICH, M., A. BATT, S. GLASSMEYER, AND J. M. LAZORCHAK. Prioritizing pharmaceuticals in municipal wastewater. Presented at SETAC North America 32nd Annual Meeting, Boston, MA, November 13 - 17, 2011.
Impact/Purpose:
These results suggest our model is useful for estimating a ceiling for exposure rates for a particular API, but often underestimate typical exposure rates, likely due to overestimates of API persistence.
Description:
Oral presentation at SETAC North America 32nd annual meeting, describing our prioritization of active pharmaceutical ingredients (APIs), based on estimates of risks posed by API residues originating from municipal wastewater. Goals of this project include prioritization of APIs for future research based on relative risks, and the estimation of absoute risks for individual APIs and their mixtures. The risk estimates were calculated as the ratio of an exposure rate estimate to an estimate of the lowest observable effect level (LOEL) for each API. The initial datasets used for exposure predictions included nationally aggregated drug sales and per capita wastewater production rates, which were combined in order to estimate wastewater influent concentrations. There are many shortcomings to these data, and no reliable estimates could be made for certain steps in the exposure model, most critically including in-plant and in-stream degradation rates. Several datasets were used to estimate the LOEL, including minimum therapeutic dose rates and plasma concentrations, both of which are typically available for this class of contaminants. The drawbacks and merits of these approaches will be discussed. For a handful of APIs, more detailed marketing data was available, allowing us to estimate site-to-site variability in exposure rates, which in turn provided the opportunity to evaluate our exposure predictions against actual measurement data.