Jul 13, 2020
In 2016, the RMP launched a novel investigation to detect new or unexpected contaminants in Bay waters, as well as treated sewage (or wastewater) discharged to the Bay. This study used non-targeted analysis, a powerful tool that provides a broad, open-ended view of thousands of synthetic and naturally-derived chemicals simultaneously. We identified hundreds of contaminants, and the results have opened our eyes to urban stormwater runoff as an important pathway for emerging contaminants to enter the Bay.
Most studies of emerging contaminants focus on chemicals we dispose of down the drain, such as pharmaceuticals or personal care and cleaning products. As a result, RMP emerging contaminant monitoring has often focused on treated sewage discharged from wastewater treatment facilities, or sites in the Lower South Bay that are strongly influenced by these discharges. However, this study shines a new light on a previously underappreciated emerging contaminant pathway — stormwater. A number of contaminants were detected in samples from San Leandro Bay, a site strongly influenced by urban stormwater runoff. Contaminants identified include many urban, industrial, and outdoor use chemicals. Based on these findings, a follow-up study to screen Bay Area stormwater for a broad array of emerging contaminants is now underway.
This recently completed factsheet outlines highlights from the screening work and specific contaminants, as well as provides further detail on the methods and drivers for non-target analysis. Funding for this study was provided by the Regional Monitoring Program for Water Quality in San Francisco Bay. Special thanks to the four Bay Area wastewater treatment facilities that voluntarily participated in the study.
Jennifer Sun, Kirsten Overdahl and Lee Ferguson of Duke University
Programs and Focus Areas:
Bay Regional Monitoring Program