Contaminant Concentrations in Sport Fish from San Francisco Bay, 2014

San Francisco Estuary Institute (SFEI) | June 1st, 2017

This summary report presents results from a 2014 survey of contaminants in San Francisco Bay sport fish, as well as an additional 2015 sampling of sport fish in Artesian

This summary report presents results from a 2014 survey of contaminants in San Francisco Bay sport fish, as well as an additional 2015 sampling of sport fish in Artesian Slough in Lower South Bay. This monitoring effort represents the seventh round of sport fish contaminant monitoring conducted by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP). This technical report is intended for agency staff charged with managing water quality issues related to bioaccumulation of contaminants in San Francisco Bay.  The RMP began sport fish monitoring in 1997, following a pilot study conducted by the Bay Protection and Toxic Cleanup Program in 1994. Data collected through this monitoring program provides updates on the status and long-term trends of contaminants in Bay sport fish, and are used to update human health consumption advisories and evaluate the effectiveness of regulatory and management efforts to reduce the impacts of contaminants of concern in the Bay. Key analyses in this report include comparisons of concentrations to human health and regulatory thresholds, spatial trend evaluation, and temporal trend evaluation.  Mercury, polychlorinated biphenyls (PCBs), dioxins, selenium, polybrominated diphenyl ethers (PBDEs), and perfluoroalkylated substances (PFASs) were analyzed across sixteen fish species collected at eight locations in San Francisco Bay and Artesian Slough. Fish species were selected based on a number of criteria, including species that are popular for consumption, are sensitive indicators of problems (accumulating relatively high concentrations of contaminants), are widely distributed, represent different exposure pathways (benthic vs. pelagic), and have been monitored in the past. Concentrations were compared to numeric human health thresholds established by the California Office of Environmental Health Hazard Assessment (OEHHA) for mercury, PCBs, selenium, and PBDEs. Results were also compared to regulatory thresholds for mercury, PCBs, and selenium, as well as non-regulatory screening value for dioxins, which have been established in Total Maximum Daily Load (TMDL) regulations by the San Francisco Bay Regional Water Quality Control Board (Water Board). 

Contaminant Concentrations in Sport Fish from San Francisco Bay: 2014

San Francisco Estuary Institute (SFEI) | January 1st, 2014

This summary report presents results from a 2014 survey of contaminants in San Francisco Bay sport fish, as well as an additional 2015 sampling of sport fish in Artesian

This summary report presents results from a 2014 survey of contaminants in San Francisco Bay sport fish, as well as an additional 2015 sampling of sport fish in Artesian Slough in Lower South Bay. This monitoring effort represents the seventh round of sport fish contaminant monitoring conducted by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP). This technical report is intended for agency staff charged with managing water quality issues related to bioaccumulation of contaminants in San Francisco Bay. The RMP began sport fish monitoring in 1997, following a pilot study conducted by the Bay Protection and Toxic Cleanup Program in 1994. Data collected through this monitoring program provides updates on the status and long-term trends of contaminants in Bay sport fish, and are used to update human health consumption advisories and evaluate the effectiveness of regulatory and management efforts to reduce the impacts of contaminants of concern in the Bay. Key analyses in this report include comparisons of concentrations to human health and regulatory thresholds, spatial trend evaluation, and temporal trend evaluation. Mercury, polychlorinated biphenyls (PCBs), dioxins, selenium, polybrominated diphenyl ethers (PBDEs), and perfluoroalkylated substances (PFASs) were analyzed across sixteen fish species collected at eight locations in San Francisco Bay and Artesian Slough. Fish species were selected based on a number of criteria, including species that are popular for consumption, are sensitive indicators of problems (accumulating relatively high concentrations of contaminants), are widely distributed, represent different exposure pathways (benthic vs. pelagic), and have been monitored in the past. Concentrations were compared to numeric human health thresholds established by the California Office of Environmental Health Hazard Assessment (OEHHA) for mercury, PCBs, selenium, and PBDEs. Results were also compared to regulatory thresholds for mercury, PCBs, and selenium, as well as non-regulatory screening value for dioxins, which have been established in Total Maximum Daily Load (TMDL) regulations by the San Francisco Bay Regional Water Quality Control Board (Water Board). The OEHHA fish consumption advisory is primarily driven by human exposure risks to mercury and PCBs. The 2014 data show that mercury and PCB concentrations remain high and widespread, indicating that these contaminants continue to pose the greatest human and wildlife health risks. Mercury concentrations exceeded OEHHA’s no consumption threshold for the sensitive population (women 18-45 and children 1-17) in several white sturgeon and striped bass samples, while PCB concentrations exceeded the no consumption threshold in Pacific sardine and white sturgeon samples. The spatial distribution of contamination has remained consistent over time, reflecting current knowledge of contaminated source areas targeted for management activities. Recent data showed no clear evidence of Bay-wide declines in either mercury or PCBs, although progressively lower PCB concentrations have been observed in recent years near Berkeley and in San Pablo Bay.

Contaminant Effects on California Bay-Delta Species & Human Health

University of California, Davis (UC Davis) | December 1st, 2016

Many contaminants in the California Bay-Delta exceed regulatory standards, impact aquatic species, and potentially affect human health. Recent studies provide evidence th

Many contaminants in the California Bay-Delta exceed regulatory standards, impact aquatic species, and potentially affect human health. Recent studies provide evidence that contaminants impact species of concern in the Bay-Delta (e.g., the decline of several important fish species referred to as the “Pelagic Organism Decline”). Multiple chemicals impair processes at cellular and physiological levels (measured as growth, development, and behavior abnormalities), ultimately affecting populations. As an important example, the population decline of the endangered delta smelt (Hypomesus transpacificus) is significantly associated with multiple stressors, including insecticide use. New analyses presented in this paper show significant correlations between pyrethroid (an insecticide) use and declining abundance of POD fish species. Water sampled from the Bay-Delta causes multiple harmful effects in fish and delta smelt. Fish prey items are also impacted by contaminants; this may have an indirect effect on their populations. Co-occurrence with thermal changes or disease can worsen contaminant effects. Contaminants also pose threats to human health via consumption of fish, drinking water, and contact recreation, in particular, mercury, toxins, disinfection byproducts, pesticides, pharmaceuticals, and personal care products. The role of contaminants in the decline of Bay-Delta species is difficult to accurately assess in a complex, dynamic system. However, tools and approaches are available to evaluate contaminant impacts on Bay-Delta species, and separate the effects of multiple stressors. Integrated monitoring and focused mechanistic studies are instrumental for addressing management needs. Impact and risk assessments should be conducted for different species across multiple life stages, with emphasis on early life stages of high-priority Bay-Delta species.  

Contaminants of Emerging Concern in San Francisco Bay: A Strategy for Future Investigations 2018 Update

San Francisco Estuary Institute (SFEI) | September 3rd, 2018

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) has been investigating contaminants of emerging concern (CECs) since 2001. CECs can be broad

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) has been investigating contaminants of emerging concern (CECs) since 2001. CECs can be broadly defined as synthetic or naturally occurring chemicals that are not regulated or commonly monitored in the environment, and have the potential to enter the environment and cause adverse ecological or human health impacts.

Contaminants of Emerging Concern in San Francisco Bay: A Strategy for Future Investigations. 2017 Revision

San Francisco Estuary Institute (SFEI) | November 1st, 2017

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

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.  As a result, a growing number of chemicals have been classified as contaminants of emerging concern (CECs), broadly defined as synthetic or naturally occurring chemicals that are not regulated or commonly monitored in the environment, but have the potential to enter the environment and cause adverse ecological or human health impacts. The primary challenge for scientists and regulators is investigating and managing this ever-expanding number of emerging contaminants to ensure that they do not harm human and ecological health. The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) has been investigating CECs since 2001, and established a formal workgroup to address the issue in 2006. The RMP Emerging Contaminants Workgroup (ECWG) includes representatives from RMP stakeholder groups, regional scientists, and an advisory panel of expert researchers that work together to address the Workgroup’s guiding management questions.

Continuous water-quality and suspended-sediment transport monitoring in San Francisco Bay, California, water years 2020–21

U.S. Geological Survey (USGS) | December 29th, 2022

Continuous Water-Quality and Suspended-Sediment Transport Monitoring in the San Francisco Bay, California, Water Years 2011–13

U.S. Geological Survey (USGS) | September 23rd, 2014

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay. The San Francisco Bay area is home to millions of peop

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay. The San Francisco Bay area is home to millions of people, and the bay teems with both resident and migratory wildlife, plants, and fish. Fresh water mixes with salt water in the bay, which is subject both to riverine and marine (tides, waves, influx of salt water) influences. To understand this environment, the USGS, along with its partners (see “Acknowledgements”), has been monitoring the bay’s waters continuously since 1988. Several water-quality variables are of particular importance to State and Federal resource managers and are monitored at key locations throughout the bay (fig. 1). Salinity, which indicates the relative mixing of fresh and ocean waters in the bay, is derived from specific conductance measurements. Water temperature, along with salinity, affects the density of water, which causes gravity driven circulation patterns and stratification in the water column. Turbidity is measured using light-scattering from suspended solids in water, and is used as a surrogate for suspended-sediment concentration (SSC). Suspended sediment often carries adsorbed contaminants; attenuates sunlight in the water column; deposits on tidal marsh and intertidal mudflats, which can help sustain these habitats as sea level rises; and deposits in ports and shipping channels, which can necessitate dredging. Dissolved oxygen, which is essential to a healthy ecosystem, is a fundamental indicator of water quality, and its concentration is affected by water temperature, salinity, ecosystem metabolism, tidal currents, and wind. Tidal currents in the bay reverse four times a day, and wind direction and intensity typically change on a daily cycle: consequently, salinity, water temperature, suspended sediment concentration, and dissolved oxygen concentration vary spatially and temporally throughout the bay, and continuous measurements are needed to observe these changes. The purpose of this fact sheet is to inform the public and resource managers of the availability of these water-quality data.

Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2016–17

U.S. Geological Survey (USGS) | April 28th, 2020

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay (Bay) as part of a multi-agency effort to add

The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay (Bay) as part of a multi-agency effort to address estuary management, water supply, and ecological concerns. The San Francisco Bay area is home to millions of people, and the Bay teems with plants and both resident and migratory wildlife, and fish. Freshwater mixes with salt water in the Bay and is subject to riverine influences (floods, droughts, managed reservoir releases, and freshwater diversions) and marine influences (tides, waves, and effects of salt water). To understand this environment, the USGS along with its cooperators (see “Acknowledgments”), has been monitoring the Bay’s waters continuously since 1988.

Contraction of the World's Storm-Cloud Zones the Primary Contributor to the 21st Century Increase in the Earth's Sunlight Absorption

American Geophysical Union (AGU) | June 8th, 2025

Recent Earth energy budget observations show an increase in the sunlight absorbed by the Earth of 0.45 W/m2 per decade, caused primarily by a decrease in cloud reflectio

Recent Earth energy budget observations show an increase in the sunlight absorbed by the Earth of 0.45 W/m2 per decade, caused primarily by a decrease in cloud reflection. Here we decompose the solar radiative budget trends into general circulation and cloud controlling process components. Regimes representing the midlatitude and tropical storm zones are defined, and the trends in the areal coverage of those regimes which are potentially induced by circulation changes are separated from trends in the cloud radiative effect within each regime which are potentially induced by changes in local cloud controlling processes. The regime area change component, which manifests itself as a contraction of the midlatitude and tropical storm regimes, constitutes the largest contribution to the solar absorption trend, causing decreased sunlight reflection of 0.37 W/m2 per decade. This result provides a crucial missing piece in the puzzle of the 21st century increase of the Earth's solar absorption.

Contraction of the World's Storm‐Cloud Zones the Primary Contributor to the 21st Century Increase in the Earth's Sunlight Absorption

American Geophysical Union (AGU) | June 8th, 2025

Recent Earth energy budget observations show an increase in the sunlight absorbed by the Earth of 0.45 W/m2 per decade, caused primarily by a decrease in cloud reflectio

Recent Earth energy budget observations show an increase in the sunlight absorbed by the Earth of 0.45 W/m2 per decade, caused primarily by a decrease in cloud reflection. Here we decompose the solar radiative budget trends into general circulation and cloud controlling process components. Regimes representing the midlatitude and tropical storm zones are defined, and the trends in the areal coverage of those regimes which are potentially induced by circulation changes are separated from trends in the cloud radiative effect within each regime which are potentially induced by changes in local cloud controlling processes. The regime area change component, which manifests itself as a contraction of the midlatitude and tropical storm regimes, constitutes the largest contribution to the solar absorption trend, causing decreased sunlight reflection of 0.37 W/m2 per decade. This result provides a crucial missing piece in the puzzle of the 21st century increase of the Earth's solar absorption.