Steven M Bay

Southern California Coastal Water Research Project | SCCWRP · Department of Toxicology

For such a humble man, his life had an outsized impact in so many ways. He rarely raised his voice, but he had a hearty laugh. Despite his competitive streak, we never saw him hold a grudge. He was honest, insightful, and treated everyone—regardless of gender, race, nationality, or religion—with respect. In his own words, “I am no different from an...

Effects‐based monitoring frameworks that combine the use of analytical chemistry with in vitro cell bioassays, and in vivo whole organism tests offer an integrative approach to broadly screen for chemical contaminants and link their presence with adverse effects on aquatic organisms. California is currently evaluating the use of such a framework to...

The objectives of this study were to investigate the contributions of sediment organochlorines (PCBs, DDTs, and chlordanes) to the water column in San Diego Bay and to evaluate the influence of these conditions on biota contamination and bioaccumulation model estimates. This study was a joint venture, conducted in partnership with the Port of San D...

This report summarizes a study evaluating the applicability of the Mulitvariate AZTI Marine Biotic Index (M-AMBI) as a benthic index that could be used in the State of California's Sediment Quality Objectives (SQO) Program. We present details of index coverage for different salinity zones of the San Francisco Bay Estuary and propose new condition c...

Toxicity tests are an important aspect of sediment quality assessments, but knowledge of the cause of toxicity is needed to determine effective management actions. Toxicity Identification Evaluation (TIE) methods were developed to meet this need. While TIE methods manuals provide information on the procedures, little information on study design is...

High-throughput cell assays that detect and integrate the response of multiple chemicals acting via a common mode of action have the potential to enhance current environmental monitoring practices. Establishing the linkage between in vitro and in vivo responses is key to demonstrate that in vitro cell assays can be predictive of ecologically releva...

The United States's Clean Water Act stipulates in section 303(d) that states must identify impaired water bodies for which total maximum daily loads (TMDLs) of pollution inputs into water bodies are developed. Decision-making procedures about how to list, or delist, water bodies as impaired, or not, per Clean Water Act 303(d) differ across states....

Urban stormwater with large impervious (paved) areas often produces runoff with a variety of contaminants. Although southern California is among the most urbanized coastal areas in the United States, the effect of rainfall variations on washoff efficiency of contaminants from pervious and impervious surfaces is largely unknown. The goal of this stu...

The use and interpretation of fish consumption surveys and interviews, the application of fish consumption rates for sediment evaluation and cleanup, and the development of human health water quality criteria (HH WQC) are complex and interrelated issues. The present article focuses on these issues using examples from the United States, although the...

Transcriptomic analysis can complement traditional ecotoxicology data by providing mechanistic insight, and by identifying sub-lethal organismal responses and contaminant classes underlying observed toxicity. Before transcriptomic information can be used in monitoring and risk assessment, it is necessary to determine its reproducibility and detect...

For sediment contaminated with bioaccumulative pollutants (e.g., PCBs and organochorine pesticides), human consumption of seafood that contain bioaccumulated sediment-derived contaminants is a well-established exposure pathway. Historically, regulation and management of this bioaccumulation pathway has focused on site-specific risk assessment. The...

This chapter serves as an initial orientation to the 2010 Gulf of Mexico deepwater horizon (DWH) oil blowout. It presents background information on past oil spills, and gives a brief summary on the Gulf of Mexico marine ecosystems. The chapter gives an overview of offshore petroleum extraction, before discussing the 2010 Deepwater Horizon Spill. It...

The Ballona Creek Estuary (BCE) in Los Angeles, California, is in a highly urbanized watershed, is contaminated by a variety of chemicals, and has prevalent sediment toxicity. Sediment cleanup targets for BCE have been established for Cu, Cd, Pb, Zn, chlordane, DDTs, PCBs, and PAHs, based on sediment quality guidelines. A sediment toxicity identifi...

There is an increasing concern approximately the presence of pharmaceutical compounds, personal care products, and other chemicals collectively known as contaminants of emerging concern (CECs) in municipal effluents. Yet, knowledge approximately potential environmental impacts related to these compounds is still limited. In the present study, we co...

Sentinel fish hornyhead turbot (Pleuronichthys verticalis) captured near wastewater outfalls are used for monitoring exposure to industrial and agricultural chemicals of ~ 20 million people living in coastal Southern California. Although analyses of hormones in blood and organ morphology and histology are useful for assessing contaminant exposure,...

Contaminants of emerging concern (CECs) in treated municipal effluents have the potential to adversely impact exposed organisms prompting elevated public concern. Using transcriptomic tools, we investigated changes in gene expression and cellular pathways in the liver of male fathead minnows (Pimephales promelas) exposed to 5% concentrations of ful...

The Southern California Bight (SCB) has undergone tremendous changes over the last 100 years resulting from natural and anthropogenic alteration of the coastal zone. A large influx of population during the 1900s has propelled the coastal community surrounding the SCB from a small pueblo (<2000 in 1900) to the largest metropolitan centre in the U.S....

To investigate the occurrence and bioaccumulation of organic contaminants of emerging concern (CECs) near four major wastewater ocean outfalls in the Southern California Bight, more than 75 pharmaceutical and personal care products, current-use pesticides, and industrial/commercial chemicals were analyzed in sediment and liver tissues of hornyhead...

The occurrence and concentrations of contaminants of emerging concern (CECs) were investigated in municipal effluents and in marine receiving water. Final effluent from four large publicly owned treatment works (POTWs) and seawater collected near the respective POTW outfall discharges and a reference station were collected quarterly over one year a...

Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were...

Municipal wastewater discharges constitute a major source of contaminants of emerging concern (CECs) to coastal waters, yet uncertainty exists regarding their linkage to adverse biological effects such as endocrine disruption. Limited information is available concerning the types and fate of CECs discharged to the Southern California Bight (SCB) fr...

As part of a regionwide collaboration to determine the occurrence of contaminants and biological effects in coastal ecosystems offshore of urban southern California, the present study characterized the reproductive endocrinology of an indigenous flatfish, the hornyhead turbot (Pleuronichthys verticalis), and compared groups sampled from different s...

Toxicity-based sediment quality guidelines (SQGs) are often used to assess the potential of sediment contamination to adversely affect benthic macrofauna, yet the correspondence of these guidelines to benthic community condition is poorly documented. This study compares the performance of 5 toxicity-based SQG approaches to a new benthos-based SQG a...

A number of sediment quality guidelines (SQGs) have been developed for relating chemical concentrations in sediment to their potential for effects on benthic macroinvertebrates, but there have been few studies evaluating the relative effectiveness of different SQG approaches. Here we apply 6 empirical SQG approaches to assess how well they predict...

Development and promulgation of sediment quality criteria represents a substantial challenge for water quality agencies. Unlike water quality programs that rely on individual chemical thresholds to assess water quality, the complex processes affecting contaminant bioavailability in sediments preclude the use of contaminant concentrations to indepen...

Integration of multiple lines of evidence (MLOE) data in a sediment quality triad assessment can be accomplished by means of numerous approaches, with most relying on some form of expert best professional judgment. Best professional judgment (BPJ) can be problematic in application to large data sets or in a regulatory setting where the assessment p...

Toxicity tests are often used in sediment assessment programs. However, the choice of methods has been largely limited to acute tests. Where sublethal methods have been used, there has been little consistency among programs in the types of the sublethal tests used. The goal of this study was to develop a method for choosing a suite of acute and sub...

Little is known about pyrethroid fate and effects in estuarine and marine environments. In the present study, the extent and magnitude of pyrethroids in coastal embayments of the Southern California Bight (SCB), USA, were assessed. Using a stratified probabilistic design, 155 sediment samples were collected from four embayment habitats (estuaries,...

Sediment toxicity was investigated at 222 stations in the Southern California Bight (SCB) during 2008. This represented the first time that assessment methods established by California's new Sediment Quality Objectives program were employed in a survey of this scale. The goal was to determine the extent and magnitude of sediment toxicity in the SCB...

The 2010 Deepwater Horizon oil release posed the challenges of two types of spill: a familiar spill characterized by buoyant oil, fouling and killing organisms at the sea surface and eventually grounding on and damaging sensitive shoreline habitats, and a novel deepwater spill involving many unknowns. The subsurface retention of oil as finely dispe...

A panel of researchers from the University of Georgia has urged the federal government to reassess how it would respond to similar oil spills that might occur in the future. According to the researchers, the 2010 Deepwater Horizon oil spill was unlike any other oil spill encountered previously. Although the well blowout occurred at unprecedented de...

The diverse mixture of contaminants frequently present in estuaries complicates their assessment by routine chemical or biological analyses. We investigated the use of gene expression to assess contaminant exposure and the condition of southern California estuarine fish. Liver gene expression, plasma estradiol concentrations, and gonad histopatholo...

Thousands of chemicals are in daily use for which little is known about their fate and effects on aquatic life. These compounds include pharmaceuticals and personal care products (PPCPs), current use pesticides (CUPs), natural and synthetic hormones, and industrial and commercial compounds (ICCs). Collectively known as contaminants of emerging conc...

There is an increasing concern about the presence of pharmaceutical compounds, personal care products, and other chemicals collectively known as contaminants of emerging concern (CECs) in municipal effluents. Yet, knowledge about potential environmental impacts related to these compounds is still limited. In this study we conducted laboratory expos...

Eight pyrethroids and fipronil and its three major degradates were analyzed in urban estuarine sediments that exhibited a range of toxic effects to an amphipod test species. Sediments from Ballona Creek, an urban estuary in Southern California (USA), collected during three dry season events were analyzed by gas chromatography with electron capture...

The State’s ability to measure and manage wetland condition is currently restricted by the lack of ability to rapidly assess contaminant effects. The goal of this project was to demonstrate the effectiveness of a gene microarray as a rapid assessment tool for wetland monitoring. This goal was successfully accomplished with the development of a micr...

Sediment-quality assessment often is hindered by the lack of agreement between chemical and biological lines of evidence. One limitation is that the bulk sediment toxicant concentration, the most widely used chemical parameter, does not always represent the bioavailable concentration, particularly for hydrophobic organic compounds (HOCs) in highly...

Endocrine disruptors include plasticizers, pesticides, detergents, and pharmaceuticals. Turbot and other flatfish are used to characterize the presence of chemicals in the marine environment. Unfortunately, there are relatively few genes of turbot and other flatfish in GenBank, which limits the use of molecular tools such as microarrays and quantit...

Background Endocrine disruptors include plasticizers, pesticides, detergents and pharmaceuticals. Turbot and other flatfish are used to characterize the presence of chemicals in the marine environment. Unfortunately, there are relatively few genes of turbot and other flatfish in GenBank, which limits the use of molecular tools such as microarrays a...

Sediment quality assessment is often hindered by the lack of agreement between chemical and biological lines of evidence. One limitation is that the bulk sediment toxicant concentration, the most widely used chemical parameter, does not always represent the bioavailable concentration, particularly for hydrophobic organic compounds (HOCs) in highly...

Sublethal test methods are being used with increasing frequency to measure sediment toxicity, but little is known about the relative sensitivity of these tests compared to the more commonly used acute tests. The present study was conducted to compare the sensitivity of several acute and sublethal methods and to investigate their correlations with s...

The toxicity of stormwater runoff during various time-based stages was measured in both grab and composite samples collected from three highly urbanized highway sites in Los Angeles, California between 2002 and 2005. Stormwater runoff samples were tested for toxicity using three freshwater species (the water flea Ceriodaphnia dubia, the fathead min...

A method using liquid chromatography/tandem mass spectrometry (LC/MS/MS) was developed for the determination of 17alpha-ethynylestradiol in fish liver; a second method using LC/MS was developed for the determination of carbamazepine, diazepam, simvastatin, and oxybenzone in fish liver. The fish liver samples were extracted and cleaned up by using l...

Sublethal test methods are being used with increasing frequency to measure sediment toxicity, but little is known about the relative sensitivity of these tests compared to the more commonly used acute tests. A study was conducted to compare the sensitivity of several acute and sublethal methods and investigate their correlations with sediment chemi...

The bioavailability of sediment-associated contaminants is poorly understood. Often, a triad of chemical concentration measurements, laboratory sediment toxicity tests, and benthic infaunal community condition is used to assess whether contaminants are present at levels of ecological concern. Integration of these 3 lines of evidence is typically ba...

Increased selenium (Se) concentrations in water (>10 μg/L) have been measured in San Diego Creek, a tributary of the Upper Newport Bay in Orange County, California. The objective of this study was to develop tissue and dietary thresholds for Se in resident fish species in San Diego Creek. A 90-day dietary experiment was conducted to determine the e...

Several types of sediment quality guidelines (SQGs) are used by multiple agencies in southern California (USA) to interpret sediment chemistry data, yet little information is available to identify the best approaches to use. The objective of this study was to evaluate the predictive ability of five SQGs to predict the presence and absence of sedime...

Increased selenium (Se) concentrations in water (>10 microg/L) have been measured in the San Diego Creek, which is a tributary of the Upper Newport Bay in Orange County, CA. The objective of this study was to develop tissue- and dietary-based thresholds for Se in resident fish species in San Diego Creek. A 90-day dietary experiment was conducted to...

This study found that DDT and its metabolic products (DDTs), technical chlordane compounds, selenium, and mercury are present and biomagnifying in the food web of the Light-footed Clapper Rail in Upper Newport Bay. Of these compounds, 4,4’-DDE is the contaminant of greatest concern. This rationale for this finding lies in 1) DDE concentrations exce...

The following consensus statements were developed regarding the ability of SQGs to predict effects or no effects in laboratory toxicity tests, benthic community assessments, or bioaccumulation assessments of sediment-dwelling organisms: • Empirically derived SQGs can be used to predict the probability of the presence or absence of toxic effects wit...

Several types of sediment quality guidelines (SQGs) are used by multiple agencies in southern California to interpret sediment chemistry data, yet little information is available to identify the best approaches to use. The objective of this study was to evaluate the performance of five SQGs to predict sediment toxicity in southern California: the e...

Stormwater runoff is an important source of toxic substances to the marine environment, but the effects of antecedent dry period, rainfall intensity, and duration on the toxicity of runoff are not well understood. In this study, simulated rainfall was applied to parking lots to examine the toxicity of runoff while controlling for antecedent period,...

The evaluation of the effects of resuspended sediments and dredging for water quality monitoring, to reduce dredging resuspension, was investigated by the southern California Contaminated Sediments Task Force (CSTF). The resuspension rates averaged slightly higher for mechanical dredging versus hydraulic dredging. The Total Suspended Sediments (TSS...

Concentrations of serum/plasma estradiol, biliary fluorescent aromatic compounds (FACs), levels of hepatic CYP1A expression, and DNA damage were measured in sexually mature hornyhead turbot (Pleuronichthys verticalis) exposed in the laboratory for 7 days to a gradient of sediments collected from a natural petroleum seep in the Santa Barbara Channel...

Rainfall during winter storms produces extensive turbid, freshwater plumes in the coastal waters of the Southern California Bight. When the plumes result from urban runoff they contain toxic pollutants along with pathogenic bacteria and viruses, often resulting in closure of public beaches. We examined the spatial structure and evolution of stormwa...

Urban stormwater runoff is a major source of contaminants to southern California's coastal waters, yet little is known about the fate and effects of these discharges. A 3-year multidisciplinary project was conducted to investigate the dispersion of stormwater plumes in Santa Monica Bay and the resultant impacts on the water column and benthos. This...