Toxicity of crude oil-derived polar unresolved complex mixtures to Pacific herring embryos: Insights beyond polycyclic aromatic hydrocarbons.

Crude oil toxicity to early life stage fish is commonly attributed to polycyclic aromatic hydrocarbons (PAHs). However, it remains unclear how the polar unresolved complex mixture (UCM), which constitutes the bulk of the water-soluble fraction of crude oil, contributes to crude oil toxicity. Additionally, the role of photomodification-induced toxicity in relation to the polar UCM is not well understood.

Using the fish plasma model to evaluate potential effects of pharmaceuticals in effluent from a large urban wastewater treatment plant.

Several pharmaceuticals and personal care products (PPCPs) were evaluated using the fish plasma model (FPM) for juvenile Chinook salmon exposed to effluent from a large urban wastewater treatment plant. The FPM compares fish plasma concentrations to therapeutic values determined in human plasma as an indication of potential adverse effects. We used human C values, which are the maximum plasma concentration for a minimum therapeutic dose.

The fish early-life stage sublethal toxicity syndrome - A high-dose baseline toxicity response.

A large number of toxicity studies report abnormalities in early life-stage (ELS) fish that are described here as a sublethal toxicity syndrome (TxSn) and generally include a reduced heart rate, edemas (yolk sac and cardiac), and a variety of morphological abnormalities. The TxSn is very common and not diagnostic for any chemical or class of chemicals. This sublethal toxicity syndrome is mostly observed at high exposure concentrations and appears to be a baseline, non-specific toxicity response; however, it can also occur at low doses by specific action.

Combined effects of crude oil exposure and warming on eggs and larvae of an arctic forage fish.

Climate change, along with environmental pollution, can act synergistically on an organism to amplify adverse effects of exposure. The Arctic is undergoing profound climatic change and an increase in human activity, resulting in a heightened risk of accidental oil spills. Embryos and larvae of polar cod (Boreogadus saida), a key Arctic forage fish species, were exposed to low levels of crude oil concurrently with a 2.

Metabolomic profiling for juvenile Chinook salmon exposed to contaminants of emerging concern.

Both targeted and non-targeted metabolomic analyses were conducted on juvenile ocean-type fall Chinook salmon (Oncorhynchus tshawytscha) residing in two estuaries receiving wastewater treatment plant (WWTP) effluent and one reference estuary. The data show that the metabolome patterns for fish from the two WWTP-receiving estuaries were more similar to each other compared to that for the reference site fish. Also, a comparison of the metabolome for fish from the reference site and fish from a hatchery upstream of one of the effluent-receiving estuaries indicated no differences, implying that residency for fish in the contaminated estuary resulted in major changes to the metabolome.

Characterizing Crude Oil Toxicity to Early-Life Stage Fish Based On a Complex Mixture: Are We Making Unsupported Assumptions?

Numerous studies of the water-soluble fraction (WSF) from crude oil have concluded that polycyclic aromatic hydrocarbons (PAHs) are the primary causative agents for early life stage (ELS) fish toxicity. Noteworthy is the lack of studies demonstrating that the sum of PAHs are capable of causing toxic effects in ELS fish at the low levels claimed (0.1-5 μg/L) without being part of a complex crude oil mixture.

Effects of dietary crude oil exposure on molecular and physiological parameters related to lipid homeostasis in polar cod (Boreogadus saida).

Polar cod is an abundant Arctic key species, inhabiting an ecosystem that is subjected to rapid climate change and increased petroleum related activities. Few studies have investigated biological effects of crude oil on lipid metabolism in this species, despite lipids being a crucial compound for Arctic species to adapt to the high seasonality in food abundance in their habitat. This study examines the effects of dietary crude oil exposure on transcription levels of genes related to lipid metabolism (peroxisome proliferator-activated receptors [ppar-α, ppar-γ], retinoic X receptor [rxr-β], palmitoyl-CoA oxidase [aox1], cytochrome P4507A1 [cyp7α1]), reproduction (vitellogenin [vtg-β], gonad aromatase [cyp19a1]) and biotransformation (cytochrome P4501A1 [cyp1a1], aryl hydrocarbon receptor [ahr2]).

Adverse metabolic effects in fish exposed to contaminants of emerging concern in the field and laboratory.

Several metabolic parameters were assessed in juvenile Chinook salmon (Oncorhynchus tshawytscha) and staghorn sculpin (Leptocottus armatus) residing in two estuaries receiving wastewater treatment effluent and one reference estuary. We also conducted a laboratory study with fish dosed for 32 days with 16 of the most common contaminants of emerging concern (CECs) detected in feral fish. Several blood chemistry parameters and other indicators of health were measured in fish from the field and laboratory study that were used to assess potential metabolic disruption.

Tributyltin: Advancing the Science on Assessing Endocrine Disruption with an Unconventional Endocrine-Disrupting Compound.

Tributyltin (TBT) has been recognized as an endocrine disrupting chemical (EDC) for several decades. However, only in the last decade, was its primary endocrine mechanism of action (MeOA) elucidated-interactions with the nuclear retinoid-X receptor (RXR), peroxisome proliferator-activated receptor γ (PPARγ), and their heterodimers. This molecular initiating event (MIE) alters a range of reproductive, developmental, and metabolic pathways at the organism level.

Determining potential adverse effects in marine fish exposed to pharmaceuticals and personal care products with the fish plasma model and whole-body tissue concentrations.

The Fish Plasma Model (FPM) was applied to water exposure and tissue concentrations in fish collected from two wastewater treatment plant impacted estuarine sites. In this study we compared predicted fish plasma concentrations to Cmax values for humans, which represents the maximum plasma concentration for the minimum therapeutic dose. The results of this study show that predictions of plasma concentrations for a variety of pharmaceutical and personal care products (PPCPs) from effluent concentrations resulted in 37 compounds (54%) exceeding the response ratio (RR = Fish [Plasma]/1%Cmax) of 1 compared to 3 compounds (14%) detected with values generated with estuarine receiving water concentrations.

Effect of contaminants of emerging concern on liver mitochondrial function in Chinook salmon.

We previously reported the bioaccumulation of contaminants of emerging concern (CECs), including pharmaceuticals and personal care products (PPCPs) and perfluorinated compounds, in field-collected juvenile Chinook salmon from urban estuaries of Puget Sound, WA (Meador et al., 2016). Although the toxicological impacts of CECs on salmon are poorly understood, several of the detected contaminants disrupt mitochondrial function in other species.

Recommended approaches to the scientific evaluation of ecotoxicological hazards and risks of endocrine-active substances.

A SETAC Pellston Workshop "Environmental Hazard and Risk Assessment Approaches for Endocrine-Active Substances (EHRA)" was held in February 2016 in Pensacola, Florida, USA. The primary objective of the workshop was to provide advice, based on current scientific understanding, to regulators and policy makers; the aim being to make considered, informed decisions on whether to select an ecotoxicological hazard- or a risk-based approach for regulating a given endocrine-disrupting substance (EDS) under review. The workshop additionally considered recent developments in the identification of EDS.

Population-relevant endpoints in the evaluation of endocrine-active substances (EAS) for ecotoxicological hazard and risk assessment.

For ecotoxicological risk assessment, endocrine disruptors require the establishment of an endocrine mode of action (MoA) with a plausible link to a population-relevant adverse effect. Current ecotoxicity test methods incorporate mostly apical endpoints although some also include mechanistic endpoints, subcellular-through-organ level, which can help establish an endocrine MoA. However, the link between these endpoints and adverse population-level effects is often unclear.

Early life stages of an arctic keystone species (Boreogadus saida) show high sensitivity to a water-soluble fraction of crude oil.

Increasing anthropogenic activities in the Arctic represent an enhanced threat for oil pollution in a marine environment that is already at risk from climate warming. In particular, this applies to species with free-living pelagic larvae that aggregate in surface waters and under the sea ice where hydrocarbons are likely to remain for extended periods of time due to low temperatures. We exposed the positively buoyant eggs of polar cod (Boreogadus saida), an arctic keystone species, to realistic concentrations of a crude oil water-soluble fraction (WSF), mimicking exposure of eggs aggregating under the ice to oil WSF leaking from brine channels following encapsulation in ice.

Contaminants of emerging concern in a large temperate estuary.

This study was designed to assess the occurrence and concentrations of a broad range of contaminants of emerging concern (CECs) from three local estuaries within a large estuarine ecosystem. In addition to effluent from two wastewater treatment plants (WWTP), we sampled water and whole-body juvenile Chinook salmon (Oncorhynchus tshawytscha) and Pacific staghorn sculpin (Leptocottus armatus) in estuaries receiving effluent. We analyzed these matrices for 150 compounds, which included pharmaceuticals, personal care products (PPCPs), and several industrial compounds.

Metal toxicity to freshwater organisms as a function of pH: A meta-analysis.

Acidification caused by climate change and seasonal fluctuation can have profound implications for chemical toxicity to freshwater organisms. The present study aims to address this challenging issue through a comprehensive meta-analysis by comparing acute median lethal or effect concentration data (LC50 or EC50) for 10 metals and metalloids for various freshwater species obtained at different pH values. Our results revealed that element toxicity generally follows three different models, including Model-I: decreasing toxicity with increasing pH, Model-II: increasing toxicity with increasing pH, and Model-III: minimal toxicity at intermediate (optimal) pH (pH(opt)) with increasing toxicity as pH increases or decreases from pH(opt).

Tissue concentrations as the dose metric to assess potential toxic effects of metals in field-collected fish: Copper and cadmium.

The present study examined the available literature linking whole-body tissue concentrations with toxic effects in fish species for copper and cadmium. The variability in effect concentration for both copper and cadmium among species occurred within an order of magnitude for all responses, whereas the range for lethal toxicity based on water exposure spanned approximately 4 to 5 orders of magnitude. Fish tissue concentrations causing adverse effects were just above background concentrations, occurring between 1 μg/g and 10 μg/g for copper and 0.

A Quantitative Microtiter Assay for Sialylated Glycoform Analyses Using Lectin Complexes.

Fidelity of glycan structures is a key requirement for biotherapeutics, with carbohydrates playing an important role for therapeutic efficacy. Comprehensive glycan profiling techniques such as liquid chromatography (LC) and mass spectrometry (MS), while providing detailed description of glycan structures, require glycan cleavage, labeling, and paradigms to deconvolute the considerable data sets they generate. On the other hand, lectins as probes on microarrays have recently been used in orthogonal approaches for in situ glycoprofiling but require analyte labeling to take advantage of the capabilities of automated microarray readers and data analysis they afford.

Controlled tetra-Fc sialylation of IVIg results in a drug candidate with consistent enhanced anti-inflammatory activity.

Despite the beneficial therapeutic effects of intravenous immunoglobulin (IVIg) in inflammatory diseases, consistent therapeutic efficacy and potency remain major limitations for patients and physicians using IVIg. These limitations have stimulated a desire to generate therapeutic alternatives that could leverage the broad mechanisms of action of IVIg while improving therapeutic consistency and potency. The identification of the important anti-inflammatory role of fragment crystallizable domain (Fc) sialylation has presented an opportunity to develop more potent Ig therapies.

Tissue-based environmental quality benchmarks and standards.

Although the use of tissue concentrations (residues) of chemical contaminants as the dose metric to characterize chemical toxicity to aquatic organisms has been gaining acceptance over the past 20 years, tissue concentrations are less commonly used in water quality management and have yet to be formally adopted as benchmarks or environmental quality standards (EQS). This synthesis paper addresses advantages and disadvantages for the development and application of tissue-based EQS as an alternative and supplement to exposure-based EQS determined with water and sediment concentration data. Tissue-based EQS can be readily developed in parallel with conventional toxicity tests, and achieved by quantification of chemical concentrations in tissue alongside traditional concentration-response toxicity testing.

In situ biomonitoring of caged, juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Lower Duwamish Waterway.

Contaminated sediments may have wide-ranging impacts on human and ecological health. A series of in situ caged exposure studies using juvenile Chinook salmon was conducted in the Lower Duwamish Waterway (LDW). Chemical analysis of sediment, water, and fish tissue were completed.

Application of the tissue residue approach in ecological risk assessment.

The objective of this work is to present a critical review of the application of the tissue residue approach (TRA) in ecological risk and/or impact assessment (ERA) of chemical stressors and environmental criteria development. A secondary goal is to develop a framework for integrating the TRA into ecological assessments along with traditional, exposure concentration-based assessment approaches. Although widely recognized for its toxicological appeal, the utility of the TRA in specific applications will depend on numerous factors, such as chemical properties, exposure characteristics, assessment type, availability of tissue residue-response data, and ability to quantify chemical exposure.