Rebecca Sutton

Virtual Forum on PFAS in San Francisco Bay Fish, February 4th, 2022

Thank you for joining environmental and public health agencies, representatives of tribes and local fishing communities, and the general public to discuss PFAS sources and the contamination of San Francisco Bay sport fish. This forum sought to build consensus for next steps to protect everyone who catches and eats fish from the Bay.

Organophosphate esters (OPEs) and bisphenols are two classes of mobile, endocrine-disrupting chemicals that are ubiquitously detected in environmental matrices due to high global production and use, particularly as plastic and polymer additives. SFEI scientists, led by Ila Shimabuku, and collaborators recently published a journal article describing a 2017 San Francisco Bay-wide Regional Monitoring Program study of 22 organophosphate esters and 16 bisphenols in open-Bay water samples. Concentrations were quantified and compared to protective ecotoxicity thresholds, where available, to assess potential risks to wildlife.

The RMP has conducted initial studies of microplastic pollution in San Francisco Bay. Findings from a 2015 screening-level RMP study of microplastic pollution in our Bay show widespread contamination at levels greater than other U.S. water bodies with high levels of urban development, the Great Lakes and Chesapeake Bay. Wildlife consume microplastic particles; ingestion can lead to physical harm, and can expose aquatic organisms to pollutants like PCBs that the plastics have absorbed from the surrounding environment.

Plastic pollution is gaining global recognition as a threat to the resilience and productivity of ocean ecosystems. However, we are only just beginning to understand the scope and impacts of microplastic particles (less than 5 mm) on coastal and ocean resources, and the San Francisco Bay Area is no exception. A preliminary study of nine water sites in San Francisco Bay, published in 2016, showed greater levels of microplastics than the Great Lakes or Chesapeake Bay.

Known as “forever chemicals” due to their persistence in the environment, per- and polyfluoroalkyl substances (PFAS) are a broad class of fluorine-rich specialty chemicals. Thousands of different PFAS are registered for use in consumer, commercial and industrial applications. Increased use has led to the widespread presence of PFAS in our natural environment, including San Francisco Bay. PFAS are a high priority for action at federal, state, and local levels due to the well-documented toxic properties of key members of this class of contaminants. 

The Regional Monitoring Program for Water Quality in San Francisco Bay is an innovative collaboration of the San Francisco Bay Regional Water Quality Control Board, the regulated discharger community, and the San Francisco Estuary Institute. It provides water quality regulators with the information they need to manage the Bay effectively. The RMP produces two types of summary reports: The Pulse of the Bay and the RMP Update. The Pulse focuses on Bay water quality and summarizes information from all sources.

What do clothes dryers and car tires have in common? Both release microplastic pollution into the environment, according to a new investigation by scientists at the San Francisco Estuary Institute. 

SFEI tracks contaminants of emerging concern (CECs), building the knowledge necessary to prevent tomorrow’s pollution problems. SFEI also aids pollution prevention efforts through our Green Chemistry focus area. Recent local and state developments on CECs and green chemistry include:

In a story called "Synthetic Clothes May Be Polluting San Francisco Bay," KGO-TV's Dan Ashley interviews SFEI's Rebecca Sutton, UC Davis professor Susan Williams, and Jim Erin from the San Jose-Santa Clara Regional Wastewater Treatment Facility about the proliferation of synthetic fibers in the Bay. Such fibers may come from fleece jackets and other clothing produced from artifical fabrics.

SFEI is working with partners across the Bay Area to design tools to help cities achieve biodiversity, stormwater, and climate benefits through multifunctional green infrastructure.

Recent studies by the San Francisco Estuary Institute (SFEI) and the Regional Monitoring Program (RMP) have pinpointed chemical and microplastic contamination from tires as a rising concern in the Bay.  Tire ingredients of interest include zinc, which has many documented adverse health effects in wildlife, and 6PPD, a preservative

Scientists at the San Francisco Estuary Institute (SFEI) have found a highly toxic tire-related contaminant at levels lethal to coho salmon in stormwater flowing through four sites in the Bay Area. The contaminant, derived from a tire preservative, has been discovered by Washington state researchers to be responsible for high levels of coho salmon deaths in Puget Sound streams. These findings will  inform a petition by state stormwater leaders to the Department of Toxic Substances Control to address pollution of California streams caused by tires.

The research team, led by scientists at the University of Washington and Washington State University, published the results of their investigation yesterday in the journal Science. The chemical, 6PPD-quinone (pronounced "kwih-known"), can wash into streams along with tire wear particles when it rains. Scientists at San Francisco Estuary Institute collected samples from nine Bay Area streams and storm drains during storm events; four contained levels of this contaminant above the concentration at which half the coho salmon die after a few hours of exposure in laboratory experiments. SFEI’s Alicia Gilbreath and Rebecca Sutton are co-authors on the study.

The California Ocean Protection Council (OPC), in close partnership with the State Water Board, has recognized the importance of standard methods for trash monitoring and has funded this project. The Southern California Coastal Water Research Project (SCCWRP) and San Francisco Bay Estuary Institute (SFEI) have partnered up to test multiple trash monitoring methods with a goal of developing a library of methods with known levels of precision, accuracy, and cross-comparability of results, and linking these methods to specific management questions.

Contaminant Data Display and Download Tool or CD3  is an innovative visualization tool for accessing water quality data for the San Francisco Bay-Delta and northern montane regions. It is the primary tool for accessing and downloading the San Francisco Bay Regional Monitoring Program’s (RMP) long-term dataset and other project data stored in SFEI's Regional Data Center (RDC).

A state-of-the-science review of current-use pesticides in wastewater, led by SFEI senior scientist Dr. Rebecca Sutton, indicates this pollution pathway is significant and should not be overlooked. The book chapter provides a comprehensive conceptual model of all types of pesticides that have the potential to be washed down the drain and into wastewater. Conventional wastewater treatment technologies are generally ineffective at removing pesticides, so additional monitoring and modeling studies are needed to guide efforts to prevent pesticide pollution.

As a result of summary information presented in the latest Pulse of the Bay (see below), the San Jose Mercury News published an article based on a RMP study of pesticide movement through Bay Area wastewater treatment plants.  Fipronil is an insecticide that is of moderate concern for the Bay because levels in sediment are in the range of toxicity thresholds for freshw

Rebecca Sutton, Meg Sedlak, and Diana Lin of SFEI, in partnership with Carolynn Box of 5 Gyres, conducted ocean water sampling associated with an ambitious project. The project is focused on determining the characteristics and fate of microplastics in the Bay and adjacent ocean waters. KQED reporter Lindsey Hoshaw published a story covering the team's activities along the California coast. After determinng that the Bay has greater than expected microplastic pollution, the science team, as reported by Hoshaw's story, is conducting further ground-breaking research.

When it comes to plastic pollution, that candy wrapper half buried in the dirt is only the tip of the iceberg. Plastic bags, cigarette butts, and bottle caps are not just an eyesore, but over time they break down in the environment, creating small pieces of debris known as microplastics. Microplastics can include anything from synthetic fibers of clothing to industrial pellets from the plastic manufacturing process. Microplastics are now ubiquitous in our environment--found in our air, drinking water, sediment, and in the San Francisco Bay and global ocean.     

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.

More than 100,000 chemicals have been registered or approved for commercial use in the US. For many of these chemicals, major information gaps limit evaluations of their potential risks, and environmental monitoring of these chemicals has not been required by regulatory agencies. Nevertheless, researchers and government agencies have begun to collect occurrence, fate, and toxicity data for a number of these chemicals.