Bifenthrin, a ubiquitous contaminant, impairs the development and behavior of the threatened Longfin Smelt during early life stages

American Chemical Society (ACS) | June 23rd, 2023

The Longfin Smelt (Spirinchus thaleichthys) population in the San Franscisco Bay/Sacramento-San Joaquin Delta (Bay-Delta) has declined to ∼1% of its pre-1980s abundance

The Longfin Smelt (Spirinchus thaleichthys) population in the San Franscisco Bay/Sacramento-San Joaquin Delta (Bay-Delta) has declined to ∼1% of its pre-1980s abundance and, as a result, is listed as threatened under the California Endangered Species Act. The reasons for this decline are multiple and complex, including the impacts of contaminants. Because the spawning and rearing seasons of Longfin Smelt coincide with the rainy season, during which concentrations of contaminants increase due to runoff, we hypothesized that early life stages may be particularly affected by those contaminants. Bifenthrin, a pyrethroid insecticide commonly used in agricultural and urban sectors, is of concern. Concentrations measured in the Bay-Delta have been shown to disrupt the behavior, development, and endocrine system of other fish species. The objective of the present work was to assess the impact of bifenthrin on the early developmental stages of Longfin Smelt. For this, embryos were exposed to 2, 10, 100, and 500 ng/L bifenthrin from fertilization to hatch, and larvae were exposed to 2, 10, and 100 ng/L bifenthrin from one day before to 3 days post-hatch. We assessed effects on size at hatch, yolk sac volume, locomotory behavior, and upper thermal susceptibility (via cardiac endpoints). Exposure to these environmentally relevant concentrations of bifenthrin did not significantly affect the cardiac function of larval Longfin Smelt; however, exposures altered their behavior and resulted in smaller hatchlings with reduced yolk sac volumes. This study shows that bifenthrin affects the fitness-determinant traits of Longfin Smelt early life stages and could contribute to the observed population decline.

Bioaccumulation of Pollutants in California Waters: A Review of Historic Data and Assessment of Impacts on Fishing and Aquatic Life

San Francisco Estuary Institute (SFEI) | October 24th, 2007

This report was written for the State Water Resources Control Board’s Surface Water Ambient Monitoring Program (SWAMP) as a step toward the development of an im

This report was written for the State Water Resources Control Board’s Surface Water Ambient Monitoring Program (SWAMP) as a step toward the development of an improved bioaccumulation monitoring program for California. The report provides a review of bioaccumulation monitoring data generated under three historic State Board programs (the Toxic Substances Monitoring Program, the State Mussel Watch Program, and the Coastal Fish Contamination Program) and other major bioaccumulation studies since 1970. Future monitoring will be guided by assessment questions developed for the SWAMP.  The objective of this report was to evaluate how well the historic data from the State Board programs and from other major monitoring efforts since 1970 address these questions. This exercise has provided a substantial amount of information about present and historical impacts of pollutant bioaccumulation on shing and aquatic life in California, and has also highlighted areas where improved sampling approaches can better address the assessment questions. Present concentrations of pollutants in many California water bodies are high enough to cause concern for possible effects on human health and to have a significant impact on the fishing beneficial use. Consumption advisories, 303(d) listings, and the bioaccumulation database as a whole provide three indices of the status of this impact. Consumption advisories exist for an increasing number of water bodies, but these represent only a fraction of the areas likely to need them. Lack of suitable data is a major impediment to developing advice for additional water bodies. A US E.P.A. evaluation of the 2002 303(d) List indicated that large portions of the state had not been assessed, especially rivers and coastline. Most of the lake area in the state (61%) had been assessed, and a relatively small percentage of the total area (6%) was classified as impaired. Assessment of lakes, however, has focused primarily on the largest lakes, leaving the vast majority of smaller lakes unsampled. Many of these small lakes are near population centers and are popular for shing. Bays and estuaries had been thoroughly assessed (98% of the area) and 93% of the total area was impaired. Evaluation of the most recent monitoring data (collected from 1998-2003) indicates that, for the locations sampled, 32% had low concentrations of pollutants, 42% had moderate concentrations, 18% had high concentrations, and 8% had very high concentrations (Figure 1). Concentrations in the low category are in a range where consumption is generally encouraged by the California Office of Environmental Health Hazard Assessment (OEHHA) (Klasing and Brodberg 2006). OEHHA is the agency responsible for managing health risks due to contaminated sport fish in California. Concentrations in the very high category are in a range where OEHHA discourages consumption (Klasing and Brodberg 2006). Lakes assigned to the moderate, high, or very high concentration categories were primarily affected by mercury, with PCBs also playing a lesser role.

Biological Condition of Non-Perennial Streams and Spring-Fed Oases in the Colorado River Basin Region

California State Water Resources Control Board (SWRCB) | August 22nd, 2014

The Colorado River Basin Regional Water Board conducted bioassessment sampling at high-quality (i.e., “reference”) streams in their region during 2013-2015. The purpo

The Colorado River Basin Regional Water Board conducted bioassessment sampling at high-quality (i.e., “reference”) streams in their region during 2013-2015. The purpose of the study was to characterize the biological condition of these streams, which had never been done before, and to expand ongoing research as to whether existing biological indices, developed primarily for perennial streams, apply in nonperennial streams. The latter are usually excluded from bioassessment surveys, but make up the majority of stream length in the most arid parts of the state like the Colorado River Basin, leaving stream condition assessments in such regions largely incomplete. The indices evaluated were the California Stream Condition Index (CSCI) based on benthic macroinvertebrates and the first to have statewide applicability in perennial streams, and the D18 and S2 indices for diatoms and soft algae, respectively, developed for use in perennial streams of southern coastal California. Sixteen sites were sampled during the 3-year period, and data loggers that measure water depth were deployed for 2 of the 3 years to characterize the hydrologic regime at each site. Most sites were nonperennial, but a few were spring-fed perennial oases. Fourteen of the sites passed formal reference screening criteria developed by statewide programs. The CSCI and S2 indices had generally good applicability in the region, with most samples from reference sites indicated either good or fair (i.e., non-degraded) biological condition. The mean CSCI score at regional reference sites was slightly lower than the statewide mean (i.e., 0.90 vs. 1.0, respectively), but the difference could be an artifact of a relatively small regional data set. The fact that CSCI and S2 performed as well as they did in a region, and in a set of stream types, largely excluded from their development indicates that the indices can be used in nonperennial streams (and spring-fed oases) in the Colorado River Basin as long as certain minimum flow conditions are met, such as sustained flow for several weeks prior to sampling and sufficient wetted width to employ existing protocols developed for perennial streams. By contrast, the D18 index did not perform well in the region. A majority of samples from reference sites indicated poor or very poor biological condition when condition thresholds based on statewide data sets were used, but even when more relaxed thresholds based on just south coast reference sites were applied, the number of reference sites in good or fair condition was still much lower than expected. This was not a result of regional reference sites being of low quality, but was most likely an artifact of applying the index to a set a stream types unintended for its use. Development of statewide algal indices is underway, which may improve the performance of diatom indices in the southern desert.

Biological opinion on the coordinated operations of the Central Valley Project (CVP) and State Water Project (SWP)

U.S. Fish and Wildlife Service (FWS) | December 15th, 2008

On May 16, 2008, the U.S. Bureau of Reclamation and the California Department of Water Resources asked the Service to initiate consultation on the Long-Term Operational C

On May 16, 2008, the U.S. Bureau of Reclamation and the California Department of Water Resources asked the Service to initiate consultation on the Long-Term Operational Criteria and Plan (OCAP) for coordination of the Central Valley Project and State Water Project, specifically concerning the delta smelt and its critical habitat. (See OCAP Legal Archives.) On December 15, 2008, the Fish & Wildlife Service issued a biological opinion (BO) on the Long-Term Operational Criteria and Plan (OCAP) for coordination of the Central Valley Project and State Water Project. The Service determined that the continued operation of these two water projects, as described in the plan, was likely to jeopardize the continued existence of the delta smelt and adversely modify its critical habitat. The inclusion by the Service of reasonable and prudent alternatives, and their acceptance by the water agencies, avoided jeopardy and adverse modification.

Biological sensitivities to high-resolution climate change projections in the California current marine ecosystem

Wiley | July 28th, 2022

Biology-based Stressor Thresholds

California State Water Resources Control Board (SWRCB) | October 1st, 2011

The objective of this memo is to describe how biological assessment data (such as those collected using Surface Water Ambient Monitoring Program (SWAMP) bioasse

The objective of this memo is to describe how biological assessment data (such as those collected using Surface Water Ambient Monitoring Program (SWAMP) bioassessment protocols) can be used to develop biologically-relevant stressor thresholds. This memo describes an objective approach for setting regulatory stressor thresholds based on the association between biological condition and stressor intensity gradients. While these relationships show a large amount of variability typical of biological data, there are clear thresholds that indicate levels below or above which stream health is maintained or degraded.

Bisphenols in San Francisco Bay: Wastewater, Stormwater, and Margin Sediment Monitoring

San Francisco Estuary Institute (SFEI) | October 28th, 2022

Bisphenols are a class of synthetic, mobile, endocrine-disrupting chemicals. Bisphenol A (BPA), the most well-studied bisphenol, is produced and used in vast quantities w

Bisphenols are a class of synthetic, mobile, endocrine-disrupting chemicals. Bisphenol A (BPA), the most well-studied bisphenol, is produced and used in vast quantities worldwide—especially in polycarbonate plastics and as a polymer additive. Recently, some manufacturers have begun using alternative bisphenol compounds, such as bisphenol F (BPF) and bisphenol S (BPS). These uses of bisphenols have led to widespread bisphenol detections in the environment and wildlife. The present study examined wastewater effluent in the San Francisco Bay Area and San Francisco Bay sediment samples for 17 bisphenols. The effluent samples were compared to available stormwater runoff data to better understand bisphenol transport, fate, and potential risks to wildlife.

Blurred lines: Multiple freshwater and marine algal toxins at the land-sea interface of San Francisco Bay, California

Harmful Algae (Elsevier) | March 10th, 2018

San Francisco Bay (SFB) is a eutrophic estuary that harbors both freshwater and marine toxigenic organisms that are responsible for harmful algal blooms. While there are

San Francisco Bay (SFB) is a eutrophic estuary that harbors both freshwater and marine toxigenic organisms that are responsible for harmful algal blooms. While there are few commercial fishery harvests within SFB, recreational and subsistence harvesting for shellfish is common. Coastal shellfish are monitored for domoic acid and paralytic shellfish toxins (PSTs), but within SFB there is no routine monitoring for either toxin. Dinophysis shellfish toxins (DSTs) and freshwater microcystins are also present within SFB, but not routinely monitored. Acute exposure to any of these toxin groups has severe consequences for marine organisms and humans, but chronic exposure to sub-lethal doses, or synergistic effects from multiple toxins, are poorly understood and rarely addressed. This study documents the occurrence of domoic acid and microcystins in SFB from 2011 to 2016, and identifies domoic acid, microcystins, DSTs, and PSTs in marine mussels within SFB in 2012, 2014, and 2015. At least one toxin was detected in 99% of mussel samples, and all four toxin suites were identified in 37% of mussels. The presence of these toxins in marine mussels indicates that wildlife and humans who consume them are exposed to toxins at both sub-lethal and acute levels. As such, there are potential deleterious impacts for marine organisms and humans and these effects are unlikely to be documented. These results demonstrate the need for regular monitoring of marine and freshwater toxins in SFB, and suggest that co-occurrence of multiple toxins is a potential threat in other ecosystems where freshwater and seawater mix.

Bottled water contaminant exposures and potential human effects

Environment International (Elsevier) | December 19th, 2022

Background: Bottled water (BW) consumption in the United States and globally has increased amidst heightened concern about environmental contaminant exposures and health

Background: Bottled water (BW) consumption in the United States and globally has increased amidst heightened concern about environmental contaminant exposures and health risks in drinking water supplies, despite a paucity of directly comparable, environmentally-relevant contaminant exposure data for BW. This study provides insight into exposures and cumulative risks to human health from inorganic/organic/microbial contaminants in BW. Methods: BW from 30 total domestic US (23) and imported (7) sources, including purified tapwater (7) and spring water (23), were analyzed for 3 field parameters, 53 inorganics, 465 organics, 14 microbial metrics, and in vitro estrogen receptor (ER) bioactivity. Health-benchmark-weighted cumulative hazard indices and ratios of organic- contaminant in vitro exposure-activity cutoffs were assessed for detected regulated and unregulated inorganic and organic contaminants. Results: 48 inorganics and 45 organics were detected in sampled BW. No enforceable chemical quality standards were exceeded, but several inorganic and organic contaminants with maximum contaminant level goal(s) (MCLG) of zero (no known safe level of exposure to vulnerable sub-populations) were detected. Among these, arsenic, lead, and uranium were detected in 67 %, 17 %, and 57 % of BW, respectively, almost exclusively in spring-sourced samples not treated by advanced filtration. Organic MCLG exceedances included frequent detections of disinfection byproducts (DBP) in tapwater-sourced BW and sporadic detections of DBP and volatile organic chemicals in BW sourced from tapwater and springs. Precautionary health-based screening levels were exceeded frequently and attributed primarily to DBP in tapwater-sourced BW and co-occurring inorganic and organic contaminants in spring-sourced BW. Conclusion: The results indicate that simultaneous exposures to multiple drinking-water contaminants of potential human-health concern are common in BW. Improved understandings of human exposures based on more environmentally realistic and directly comparable point-of-use exposure characterizations, like this BW study, are essential to public health because drinking water is a biological necessity and, consequently, a high vulnerability vector for human contaminant exposures.

Brackish Water Desalination Facility Project

Delta Stewardship Council (Delta Council) | April 1st, 2020

The City of Antioch (City) is proposing the Brackish Water Desalination Project (Project), which consists of the construction of a desalination facility at the City’s

The City of Antioch (City) is proposing the Brackish Water Desalination Project (Project), which consists of the construction of a desalination facility at the City’s water treatment plant (WTP) with the capacity to produce up to 6 million gallons per day (mgd) of finished water; demolition of the existing San Joaquin River intake pump station; construction of a new intake pump station; approximately 3,000 feet of pipeline from the existing raw water pipeline underneath Lone Tree Way to the City’s WTP to allow a direct connection to maximize use of existing infrastructure; and approximately 4 miles of pipeline from the desalination facility to the Delta Diablo wastewater treatment plant (WWTP) to discharge brine with the WWTP effluent through the existing Delta Diablo outfall to New York Slough. The Project facilities would be located in the cities of Antioch and Pittsburg, California (Figure 1), at the western edge of the San Joaquin- Sacramento Delta (Delta). The main objectives of the Project are to improve water supply reliability and water quality for its customers; develop a reliable and drought-resistance water source to reduce dependency on purchased water supplies; maximize and preserve the use of the City’s pre-1914 water rights; and provide cost effective operational flexibility for the City.