Abstract

Disinfectants, most notably Triclosan (TCS) and Triclocarban (TCC), are of increasing concern in wastewaters as a result of the realization of their potential threats to humans and aquatic ecology, in combination with their frequent detections in wastewater treatment plant (WWTP) effluents. These concerns are driven by the known limited removal capabilities of both TCS and TCC in conventional water and wastewater treatment processes, as well as their potential to form toxic intermediates. Given these concerns, results from a monitoring program are described associated with hospitals, funeral homes, slaughterhouses and residential neighborhoods. Specifically, when the contributions due to hospitals, funeral homes and slaughterhouses are compared to the total at the wastewater treatment influent, results show that hospitals account for <8.2% of the mass loading, indicating that health care centers are substantial point sources for TCS and TCC in wastewater treatment systems. but slaughterhouses and funeral homes contributed less than 0.1% and 0.6 % of the overall loading of disinfectants, indicating that household and other industrial uses are responsible for larger mass loadings.

Combining the monitoring results with reported technical literature values show substantial variabilities from one source and location to another, indicating that no simple procedure will predict typical disinfectant levels in hospital wastewaters. However, by aggregating available technical data in combination the findings from this study, 95% UCL for average concentrations of 70,800ng/L for TCS and 197ng/L for TCC are demonstrated, providing insights as to magnitudes of the individual disinfectants.

Keywords: Triclosan; Triclocarban; Emerging contaminants; Municipal wastewater; Hospitals; Funeral homes; Slaughterhouse