Physical Sciences and Mathematics Commons^™

Sorption Of Representative Organic Contaminants On Microplastics: Effects Of Chemical Physicochemical Properties, Particle Size, And Biofilm Presence, Wenxuan Cui, Robert C. Hale, Yichao Huang, Et Al.

VIMS Articles

Microplastic pollution has attracted mounting concerns worldwide. Microplastics may concentrate organic and metallic contaminants; thus, affecting their transport, fate and organismal exposure. To better understand organic contaminant-microplastic interactions, our study explored the sorption of selected polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), α-hexabromocyclododecane (α-HBCDD), and organophosphate flame retardants (OPFRs) on high-density polyethylene (HDPE) and polyvinylchloride (PVC) microplastics under saline conditions. Sorption isotherms determined varied between chemicals and between HDPE and PVC microplastics. Log Freundlich sorption coefficients (Log K_F) for the targeted chemicals ranged from 2.01 to 5.27 L kg^-1 for HDPE, but were significantly lower for PVC, …

Sediment Metagenomics Reveals The Impacts Of Poultry Industry Wastewater On Antibiotic Resistance And Nitrogen Cycling Genes In Tidal Creek Ecosystems, Miguel Semedo, Bongkeun Song

VIMS Articles

The intensification of the poultry industry may lead to the increased spread of antibiotic resistance genes (ARGs) in the environment. However, the impacts of wastewater discharge from poultry processing plants on the sediment resistome are relatively unexplored. Furthermore, its relationships with important biogeochemical pathways, such as the N cycle, are virtually unknown. The overall objective of this study was to examine the abundance and diversity of antibiotic resistance and N cycling genes in sediment microbial communities impacted by poultry industry wastewater. We performed a metagenomic investigation of sediments in an impacted and a reference tidal creek. We also quantified the …

Immunofluorescence Visualization Of Polycyclic Aromatic Hydrocarbon Mixtures In The Eastern Oyster Crassostrea Virginica, Kristen M. Prossner, Hamish J. Small, Ryan Carnegie, Michael A. Unger

VIMS Articles

Bivalve mollusks including oysters have low metabolic potential and are therefore susceptible to accumulating high levels of lipophilic organic contaminants such as polycyclic aromatic hydrocarbons (PAHs). Human exposure to PAHs via consumption of this important commercial shellfish can be a serious public health concern in areas where high PAH contamination exists. Previous PAH immunohistochemical studies have been limited to laboratory-based exposures focusing on one or a few individual PAH compounds. To date, such studies have yet to explore PAH accumulation in oysters, known to have some of the highest levels of PAHs across different food products. Using a monoclonal antibody …

A Novel Antibody-Based Biosensor Method For The Rapid Measurement Of Pah Contamination In Oysters, Kristen M. Prossner, George G. Vadas, Ellen Harvey, Michael A. Unger

VIMS Articles

Conventional PAH analytical methods are time-consuming and expensive, limiting their utility in time sensitive events (i.e. oil spills and floods) or for widespread environmental monitoring. Unreliable and inefficient screening methods intended to prioritize samples for more extensive analyses exacerbate the issue. Antibody-based biosensor technology was implemented as a quantitative screening method to measure total PAH concentration in adult oysters (Crassostrea virginica) — a well-known bioindicator species with ecological and commercial significance. Individual oysters were analyzed throughout the historically polluted Elizabeth River watershed (Virginia, USA). Significant positive association was observed between biosensor and GC–MS measurements that persisted when the method was …

Joint Effects Of Fragmentation And Mercury Contamination On Marsh Periwinkle (Littoraria Irrorata) Movement, Marcos Krull, Michael C. Newman

VIMS Articles

There are different ways contaminants can interact and enhance the effects of habitat fragmentation, such as modifying the movement of organisms. The present study tested the hypothesis that mercury exacerbates the effects of
fragmentation by affecting the movement of the marsh periwinkle Littoraria irrorata and reducing the probability of snails crossing fragmented microlandscape experimental systems. How these changes could affect the search efficiency of organisms in the long term was assessed using hidden Markov models and random walks simulations. Bayesian nonlinear
models were used to analyze the effects of fragmentation and contamination on the mean speed and mean directional change …

Evaluation Of A Rapid Biosensor Tool For Measuring Pah Availability In Petroleum-Impacted Sediment, Jason Conder, Mehregan Jalalizadeh, (...), Michael A. Unger

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Decades of research have shown that the concentration of freely dissolved PAH (C_free) in sediment correlates with PAH bioavailability and toxicity to aquatic organisms. Passive sampling techniques and models have been used for measuring and predicting C_free, respectively, but these techniques require weeks for analytical chemical measurements and data evaluation. This study evaluated the performance of a portable, field-deployable antibody-based PAH biosensor method that can provide measurements of PAH C_free within a matter of minutes using a small volume of mechanically-extracted sediment porewater. Four sediments with a wide range of PAHs (ΣPAH 2.4 to 307 …

Flame Retardants, Dioxins, And Furans In Air And On Firefighters’ Protective Ensembles During Controlled Residential Firefighting, Kenneth W. Fent, Mark J. La Guardia, Drew Luellen, Et Al

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Structure fires that involve modern furnishings may emit brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs), as well as brominated and chlorinated dioxins and furans, into the environment.

The goal of this study was to quantify the airborne and personal protective equipment (PPE) contamination levels of these compounds during controlled residential fires in the U.S., and to evaluate gross-decontamination measures.

Single-Use Plastics And Covid-19: Scientific Evidence And Environmental Regulations, Robert C. Hale, Bk Song

VIMS Articles

Waste plastics are a serious and growing environmental problem. Less than 10% of plastics are recycled, with most discarded in landfills, incinerated, or simply abandoned.1 Single-use plastics constitute about half of plastic waste. While most plastics are used and initially disposed of on land, much eventually enters aquatic ecosystems.2 Wildlife mortalities result from encounters (e.g., ingestion and entanglement) with large debris, including plastic bags. Such bags are excluded from many recycling programs, as they can entangle machinery. Most plastics do not readily biodegrade in the environment. However, they can be embrittled by UV exposure and fragment into microplastics (mm) and …

Current And Future Remote Sensing Of Harmful Algal Blooms In The Chesapeake Bay To Support The Shellfish Industry, Jl Wolny, Mc Tomlinson, S Schollaert Uz, Ta Egerton, Jr Mckay, A Meredith, Ks Reece, Gp Scott, Rp Stumpf

VIMS Articles

Harmful algal bloom (HAB) species in the Chesapeake Bay can negatively impact fish, shellfish, and human health via the production of toxins and the degradation of water quality. Due to the deleterious effects of HAB species on economically and environmentally important resources, such as oyster reef systems, Bay area resource managers are seeking ways to monitor HABs and water quality at large spatial and fine temporal scales. The use of satellite ocean color imagery has proven to be a beneficial tool for resource management in other locations around the world where high-biomass, nearly monospecific HABs occur. However, remotely monitoring HABs …

A Global Perspective On Microplastics, Robert Hale, Meredith E. Seeley, Mark J. La Guardia, Lei Mai, Eddy Y. Zeng

VIMS Articles

Society has become increasingly reliant on plastics since commercial production began in about 1950. Their versatility, stability, light weight, and low production costs have fueled global demand. Most plastics are initially used and discarded on land. Nonetheless, the amount of microplastics in some oceanic compartments is predicted to double by 2030. To solve this global problem, we must understand plastic composition, physical forms, uses, transport, and fragmentation into microplastics (and nanoplastics). Plastic debris/microplastics arise from land disposal, wastewater treatment, tire wear, paint failure, textile washing, and at‐sea losses. Riverine and atmospheric transport, storm water, and disasters facilitate releases. In surface …

Microplastics Affect Sedimentary Microbial Communities And Nitrogen Cycling, Meredith E. Seeley, Bk Song, Renia Passie, Robert C. Hale

VIMS Articles

Microplastics are ubiquitous in estuarine, coastal, and deep sea sediments. The impacts of microplastics on sedimentary microbial ecosystems and biogeochemical carbon and nitrogen cycles, however, have not been well reported. To evaluate if microplastics influence the composition and function of sedimentary microbial communities, we conducted a microcosm experiment using salt marsh sediment amended with polyethylene (PE), polyvinyl chloride(PVC), polyurethane foam (PUF) or polylactic acid (PLA) microplastics. We report that the presence of microplastics alters sediment microbial community composition and nitrogen cycling processes. Compared to control sediments without microplastic, PUF- and PLA-amended sediments promote nitrification and denitrification, while PVC amendment inhibits …

Organophosphate And Novel Brominated Flame Retardants Exposure In Childbearing Women Via House Dust, Z. Percy, Mark J. La Guardia, Y. Xu, Robert Hale, B. Lanphear

VIMS Articles

No abstract provided.

Assessment Of Spray Polyurethane Foam Worker Exposure To Organophosphate Flame Retardants Through Measures In Air, Hand Wipes, And Urine, Cf Estill, J Slone, Et Al, Mark J. La Guardia, Et Al

VIMS Articles

Tris(1-chloro-2-propyl) phosphate (TCPP, also referenced as TCIPP), a flame retardant used in spray polyurethane foam insulation, increases cell toxicity and affects fetal development. Spray polyurethane foam workers have the potential to be exposed to TCPP during application. In this study, we determined exposure to TCPP and concentrations of the urinary biomarker bis(1-chloro-2-propyl) phosphate (BCPP) among 29 spray polyurethane foam workers over 2 work days. Work was conducted at residential or commercial facilities using both open-cell (low density) and closed-cell (high density) foam. Study participants provided two personal air samples (Day 1 and Day 2), two hand wipe samples (Pre-shift Day …

Firefighter Hood Contamination: Efficiency Of Laundering To Remove Pahs And Frs, Ac Mayer, Kw Fent, S Bertke, Gp Horn, Dl Smith, K Kerber, Mark J. La Guardia

VIMS Articles

Firefighters are occupationally exposed to products of combustion containing polycyclic aromatic hydrocarbons (PAHs) and flame retardants (FRs), potentially contributing to their increased risk for certain cancers. Personal protective equipment (PPE), including firefighter hoods, helps to reduce firefighters’exposure to toxic substances during fire responses by providing a layer of material on which contaminants deposit prior to reaching the firefighters skin.However, over time hoods that retain some contamination may actually contribute to fire-fighters’systemic dose. We investigated the effectiveness of laundering to reduce or remove contamination on the hoods, specifically PAHs and three classes of FRs: polybrominateddiphenyl ethers (PBDEs), non-PBDE flame retardants (NPBFRs), …

Addressing The Issue Of Microplastics In The Wake Of The Microbead-Free Waters Act - A New Standard Can Facilitate Improved Policy, Jason P. Mcdevitt, Craig S. Criddle, Molly Morse, Robert Hale, Et Al

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The United States Microbead-Free Waters Act was signed into law in December 2015. It is a bipartisan agreement that will eliminate one preventable source of microplastic pollution in the United States. Still, the bill is criticized for being too limited in scope, and also for discouraging the development of biodegradable alternatives that ultimately are needed to solve the bigger issue of plastics in the environment. Due to a lack of an acknowledged, appropriate standard for environmentally safe microplastics, the bill banned all plastic microbeads in selected cosmetic products. Here, we review the history of the legislation and how it relates …

Regression Or Significance Tests: What Other Choice Is There?—An Academic Perspective, Michael C. Newman, Marcos Krull

VIMS Articles

Both the no-observed-effect concentration and its null hypothesis significance testing foundation have drawn steady criticism since their inceptions [1–5]. Many in our field reasonably advocate regression to avoid conventional null hypothesis significance testing shortcomings; however, regression is compromised under commonly encountered conditions (Green, present Perspective’s Challenge). As the debate to favor null hypothesis significance testing or regression methods continues into the 21st century, a sensible strategy might be to take a moment to ask, Are there now other choices? Our goal is to sketch out 1 such choice.

Decadal Re-Evaluation Of Contaminant Exposure And Productivity Of Ospreys (Pandion Haliaetus) Nesting In Chesapeake Bay Regions Of Concern, Rs Lazarus, Ba Rattner, Pc Mcgowan, Robert Hale, Et Al

VIMS Articles

The last large-scale ecotoxicological study of ospreys (Pandion haliaetus) in Chesapeake Bay was conducted in 2000-2001 and focused on U.S. EPA-designated Regions of Concern (ROCs; Baltimore Harbor/Patapsco, Anacostia/middle Potomac, and Elizabeth Rivers). In 2011-2012, ROCs were re-evaluated to determine spatial and temporal trends in productivity and contaminants. Concentrations of p,p'-DDE were low in eggs and below the threshold associated with eggshell thinning. Eggs from the Anacostia/middle Potomac Rivers had lower total PCB concentrations in 2011 than in 2000; however, concentrations remained unchanged in Baltimore Harbor. Polybrominated diphenyl ether flame retardants declined by 40%, and five alternative brominated flame retardants were …

Regression Or Significance Tests: What Other Choice Is There?-An Academic Perspective Response, Mc Newman, M Krull

VIMS Articles

Both the no-observed-effect concentration and its null hypothesis significance testing foundation have drawn steady criticism since their inceptions [1–5]. Many in our field reasonably advocate regression to avoid conventional null hypothesis significance testing shortcomings; however, regression is compromised under commonly encountered conditions (Green,present Perspective’s Challenge). As the debate to favor null hypothesis significance testing or regression methods continues into the 21st century, a sensible strategy might be to take a moment to ask, Are there now other choices? Our goal is to sketch out 1 such choice.

Scientific Evidence Supports A Ban On Microbeads, Cm Rochman, Sm Kross, Jb Armstrong, Mt Bogan, Es Darling, Sj Green, Ar Smyth, D Verissimo

VIMS Articles

No abstract provided.

Projected Hg Dietary Exposure Of 3 Bird Species Nesting On A Contaminated Floodplain (South River, Virginia, Usa), Jc Wang, Mc Newman

VIMS Articles

Dietary Hg exposure was modeled for Carolina wren (Thryothorus ludovicianus), Eastern song sparrow (Melospiza melodia), and Eastern screech owl (Otus asio) nesting on the contaminated South River floodplain (Virginia, USA). Parameterization of Monte-Carlo models required formal expert elicitation to define bird body weight and feeding ecology characteristics because specific information was either unavailable in the published literature or too difficult to collect reliably by field survey. Mercury concentrations and weights for candidate food items were obtained directly by field survey. Simulations predicted the probability that an adult bird during breeding season would ingest specific amounts of Hg during daily foraging …

Liver Carcinogenesis In A Non-Migratory Fish: The Association With Polycyclic Aromatic Hydrocarbon Exposure, Wolfgang K. Vogelbein, M. A. Unger

VIMS Articles

Field and laboratory studies indicate a strong positive association between exposure to chemical pollutants in aquatic environments and development of neoplasia in fishes. This brief communication reviews some of the more important North American and European studies that have been conducted on this relationship. We then review work conducted on a small nonmigratory estuarine cyprinodontid teleost fish, the mummichog (Fundulus heteroclitus) in the industrialized Elizabeth River, Virginia USA. Histopathological surveys of mummichogs from variously degraded habitats indicate an association between PAH exposure and development of neoplasia. We have observed non-neoplastic lesions, preneoplasms and hepatic, biliary, exocrine pancreatic and vascular neoplasms …

Characterization Of The Dust/Smoke Aerosol That Settled East Of The World Trade Center (Wtc) In Lower Manhattan After The Collapse Of The Wtc 11 September 2001, Paul J. Lioy, Clifford P. Weisel, Et Al, Robert C. Hale

VIMS Articles

The explosion and collapse of the World Trade Center (WTC) was a catastrophic event that produced an aerosol plume impacting many workers, residents, and commuters during the first few days after 11 September 2001. Three bulk samples of the total settled dust and smoke were collected at weather-protected locations east of the WTC on 16 and 17 September 200 1; these samples are representative of the generated material that settled immediately after the explosion and fire and the concurrent collapse of the two structures. We analyzed each sample, not differentiated by particle Size, for inorganic and organic composition. In the …

The Practice Of Structure Activity Relationships (Sar) In Toxicology, James D. Mckinney, Ann Richard, Chris Waller, Michael C. Newman, Frank Gerberick

VIMS Articles

No abstract provided.

Phenotypic Selection In An Intertidal Snail: Effects Of A Catastrophic Storm, G. Trussell

VIMS Articles

Littorina obtusata exhibits clear morphological variation (e.g. shell height, shell length, and aperture area) among shores differentially exposed to wave energies. Selection imposed by the hydrodynamic environment is often invoked to explain the correlation between morphology and wave exposure in intertidal organisms, but rarely is this hypothesis tested. I examined the effects of a catastrophic storm on the shell length and relative shell height and aperture area of L. obtusata populations on 2 protected and 1 wave-exposed share in New England (USA) to test this hypothesis. Snails sampled after the storm had relatively squatter shells than those sampled before the …

Research Needs For The Risk Assessment Of Health And Environmental Effects Of Endocrine Disruptors: A Report Of The Us Epa-Sponsored Workshop, Rj Kavlock, Gp Daston, C Derosa, P Fennercrisp, Le Gray, S Kaattari, Et Al

VIMS Articles

The hypothesis has been put forward that humans and wildlife species have suffered adverse health effects after exposure to endocrine-disrupting chemicals. Reported adverse effects include declines in populations, increases in cancers, and reduced reproductive function. The U.S. Environmental Protection Agency sponsored a workshop in April 1995 to bring together interested parties in an effort to identify research gaps related to this hypothesis and to establish priorities for future research activities. Approximately 90 invited participants were organized into work groups developed around the principal reported health effects-carcinogenesis, reproductive toxicity, neurotoxicity, and immunotoxicity--as well as along the risk assessment paradigm--hazard identification, dose-response …

Evaluation Of Gas-Chromatography With Electrolytic Conductivity Detection And Electron-Capture Detection And Use Of Negative Chemical Ionization Gc-Ms For The Analysis Of Pcbs In Effluents, J Greaves, E Harvey, Rj Huggett

VIMS Articles

Gas chromatography with electrolytic conductivity detection and electron capture detection in combination with gas chromatography-mass spectrometry, operated in the electron capture negative chemical ionization mode, were evaluated as techniques for the analysis of polychlorinated biphenyls in wastewater from an industrial facility. The specificity of the electrolytic conductivity detector reduced sample turnaround time because extracts could be analyzed without fractionation or cleanup. Using a 2-L sample, this methodology had a quantification limit, based on Aroclor 1260, of 0.1-mu-g/L and a detection limit of approximately 0.03-mu-g/L. The electron capture detector was subject to interferences from nonhalogenated compounds and required additional sample cleanup. …

Determination Of Tributyltin In The Marine-Environment, Rg Huggett, Michael A. Unger, Fa Espourteille, Cd Rice

VIMS Articles

Tributyltin (TBT) is a biocide used in antifouling paints to protect hulls from nuisance organisms such as barnacles, worms and algae. The use of TBT paints has increased over the past decade due to its effectiveness as an antifoulant which is related to its toxicity. Water concentrations of less than 100 ng L- have been shown to harm some aquatic species in laboratory tests and observations in the natural environment indicate that levels below 10 ng L- may be harmful. Tributyltin is bioconcentrated by many species to levels of one thousand, or more, times ambient water concentrations. Sediment-water partitioning coefficients …