Geology topics

Adria Elskus

Publications and source records attributed to Adria Elskus.

10 recordsLinked to original sources

USGS2020

Monitoring chemical contaminants in the Gulf of Maine, using sediments and mussels (Mytilus edulis): An evaluation

The objective of this paper is to determine whether contaminant data on mussels and sediments can be used interchangeably, or not, when assessing the degree of anthropogenic contamination of a water body. To obtain adequate coverage of the entire Gulf of Maine, Bay of Fundy sediment samples were collected, analyzed and combined with similar data from four coastal monitoring programs. This required careful interpretation but provided robust results consistent with published literature. A strong correspondence was found between sediment and mussel concentrations for polycyclic aromatic hydrocarbons, moderate to weak correspondence for polychlorinated biphenyls, and except for mercury and zinc, little to no correspondence was found for metals. We conclude that mussel contaminant data are likely sufficient for providing information on the spatial and temporal distribution of chemical contaminants, in coastal waters, under a broad range of environmental conditions and contaminant levels, and unlike sediments, provide direct information on contaminant bioavailability.

Gulf of Maine↗

USGS2020

The collection and analysis of Bay of Fundy sediment under contract between the association of US delegates to the Gulf of Maine Council on the marine environment and eastern Charlotte waterways for contaminant monitoring and analysis

This report presents data obtained through the EcoSystem Indicator Partnership (ESIP) which was established in 2006 to improve understanding and to inform researchers, managers, and citizens about the status and trends of ecosystem health in the Gulf of Maine (http://www.gulfofmaine.org/2/esip-homepage/). In its efforts to compile information on contaminant indicators in the Gulf of Maine, ESIP identified gaps in monitoring information and worked in partnership with the Gulf of Maine Council and other organizations to fill these gaps. The monitoring and data gaps identified by ESIP indicated that data on contaminants in intertidal/subtidal sediments were lacking for the Bay of Fundy. To address this data gap, the Association of US Delegates to the Gulf of Maine Council on the Marine Environment contracted Eastern Charlotte Waterways Inc., an independent non-governmental organization, to conduct a contaminant monitoring and analysis project funded by Environment and Climate Change Canada . This report summarizes the data produced from this sediment analysis project.

Gulf of Maine↗

USGS2017

Chronic toxicity of azoxystrobin to freshwater amphipods, midges, cladocerans, and mussels in water-only exposures

Understanding the effects of fungicides on nontarget organisms at realistic concentrations and exposure durations is vital for determining potential impacts on aquatic ecosystems. Environmental concentrations of the fungicide azoxystrobin have been reported up to 4.6 μg/L in the United States and 30 μg/L in Europe. The objective of the present study was to evaluate the chronic toxicity of azoxystrobin in water-only exposures with an amphipod ( Hyalella azteca ; 42-d exposure), a midge ( Chironomus dilutus ; 50-d exposure), a cladoceran ( Ceriodaphnia dubia ; 7-d exposure), and a unionid mussel ( Lampsilis siliquoidea ; 28-d exposure) at environmentally relevant concentrations. The potential photo-enhanced toxicity of azoxystrobin accumulated by C. dubia and L. siliquoidea following chronic exposures to azoxystrobin was also evaluated. The 20% effect concentrations (EC20s) based on the most sensitive endpoint were 4.2 μg/L for H. azteca reproduction, 12 μg/L for C. dubia reproduction and C. dilutus emergence, and >28 μg/L for L. siliquoidea . Hyalella azteca was more sensitive to azoxystrobin compared with the other 3 species in the chronic exposures. No photo-enhanced toxicity was observed for either C. dubia or L. siliquoidea exposed to ultraviolet light in control water following azoxystrobin tests. The results of the present study indicate chronic effects of azoxystrobin on 3 of 4 invertebrates tested at environmentally relevant concentrations. The changes noted in biomass and reproduction have the potential to alter the rate of ecological processes driven by aquatic invertebrates. Environ Toxicol Chem 2017;9999:1–8. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Environmental Toxicology and Chemistry↗

USGS2017

Efficacy and residual toxicity of a sodium hydroxide based ballast water treatment system for freshwater bulk freighters

The efficacy and residual toxicity of a sodium hydroxide (NaOH) based ballast water treatment system (BWTS) were tested aboard the Great Lakes carrier M/V American Spirit in 1000 L mesocosms containing water from the ship's ballast tanks. NaOH was added to elevate the pH to 11.5 or 11.7 for 48 h, after which pH was reduced to < 9 before discharge by sparging with carbon dioxide to form sodium bicarbonate. In 4 trials, pH 11.7 NaOH BW was highly effective in reducing the densities of organisms relative to uptake water and met the ballast water discharge standards of the US Coast Guard (USCG), the US Environmental Protection Agency vessel general permit (USEPA VGP) and the International Maritime Organization (IMO) G8 for the classes of regulated organisms: ≥ 50 μm, ≥ 10 μm to < 50 μm and indicator bacteria < 10 μm. In addition, densities of heterotrophic bacteria were reduced > 96% in pH 11.7 treated discharge water relative to uptake densities. Seven day whole effluent toxicity tests indicated pH 11.7 NaOH BW met the USEPA VGP daily maximum criteria for residual toxicity. Organism densities in uptake water did not meet the minimum densities for IMO G8 shipboard test validity in 2 of 4 trials for organisms ≥ 10 μm to < 50 μm or in any trials for the < 10 μm size class. The high efficacy and low residual toxicity observed indicates that a NaOH BWTS has great potential for successfully treating large volumes of ballast water released into freshwater systems.

Journal of Great Lakes Research↗

USGS2017

Have mummichog (Fundulus heteroclitus) from the lower Penobscot River, Maine, developed tolerance to the toxic effects of mercury?

Fish populations that are chronically exposed to mercury (Hg) can develop resistance to the toxic effects of this metal, including mummichog (Fundulus heteroclitus; Weis 2002). Such resistance allows them to potentially accumulate very high levels of this contaminant (Stefansson et al. 2013). Mercury is a neurotoxin that affects behavior in fish, including swimming and the ability to capture prey (Samson et al. 2001, Zhou et al. 2001), and behavior, reproduction and immune function in birds (Evers et al. 2008, Hawley et al. 2009). Ingestion of mercury-contaminated prey could have significant, and severe, effects on migratory fish and piscivorous birds, including loons (Evers et al. 2008). We found that mercury concentrations in resident mummichog collected from sites in the lower Penobscot River in 2011 were 9 to 16 times higher than Hg levels in mummichog from a control site in Wells, Maine (Elskus 2012). For part one of this study, reproductively mature male and female mummichog were collected in Fall 2015 from two sites in Maine: Bald Hill Cove, a mercury-contaminated site along the mercury gradient of the Penobscot River, and Drake, a reference site at the Wells National Estuarine Research Reserve. These parental fish were housed at the US EPA laboratory (Narragansett, RI). Beginning in Spring 2016, these fish were fed diets containing either low or high concentrations of mercury for 28 days. Embryos were collected from these parents and divided into subsets. One subset was used to measure the mercury concentrations in the embryos, the second subset was shipped to the University of Maine where they were hatched, and the larval fish evaluated for behavioral effects. For part two of this study, adult mummichog were collected from Hg-contaminated Bald Hill Cove and from a reference site, Wells, in the Wells National Estuarine Reserve and evaluated for mercury body burdens and behavior. In Study 1, mercury was maternally transferred to the progeny demonstrating this is one pathway of generational exposure to mercury. Unfortunately, all larvae from the mercury-contaminated Bald Hill Cove population died before behavioral analysis could be done. Behavioral studies of the reference Drake population, however, demonstrated no significant differences between offspring of parents fed high mercury diets and offspring of parents fed low mercury diets. In Study 2, adult fish from the mercury contaminated BHC population had mercury body burdens that were four times higher than those in the reference Wells population, but while fewer BHC adults performed prey strikes than the Wells adults, there were no other significant behavioral differences between the two populations. In conclusion, the main hypothesis, that fish from the site receiving chronic mercury exposure had developed resistance to mercury toxicity, could not be definitively determined due to the death of embryos from the chronically exposed population. However, the present study did reveal some behavioral effects associated with mercury exposure that warrant further study. Behavioral approaches are important because they address some of the basic and difficult questions surrounding contaminant exposures; namely that sub-lethal effects are important to evaluate because they may have consequences for individual and perhaps population survival.

Maine↗

USGS2016

Effects of 2 fungicide formulations on microbial and macroinvertebrate leaf decomposition under laboratory conditions

Aquatic fungi contribute significantly to the decomposition of leaves in streams, a key ecosystem service. However, little is known about the effects of fungicides on aquatic fungi and macroinvertebrates involved with leaf decomposition. Red maple (Acer rubrum) leaves were conditioned in a stream to acquire microbes (bacteria and fungi), or leached in tap water (unconditioned) to simulate potential reduction of microbial biomass by fungicides. Conditioned leaves were exposed to fungicide formulations QUILT (azoxystrobin + propiconazole) or PRISTINE (boscalid + pyraclostrobin), in the presence and absence of the leaf shredder, Hyalella azteca (amphipods; 7-d old at start of exposures) for 14 d at 23 °C. QUILT formulation (~ 0.3 μg/L, 1.8 μg/L, 8 μg/L) tended to increase leaf decomposition by amphipods (not significant) without a concomitant increase in amphipod biomass, indicating potential increased consumption of leaves with reduced nutritional value. PRISTINE formulation (~ 33 μg/L) significantly reduced amphipod growth and biomass (p<0.05), effects similar to those observed with unconditioned controls. The significant suppressive effects of PRISTINE on amphipod growth, and the trend towards increased leaf decomposition with increasing QUILT concentration, indicate the potential for altered leaf decay in streams exposed to fungicides. Further work is needed to evaluate fungicide effects on leaf decomposition under conditions relevant to stream ecosystems, including temperature shifts and pulsed exposures to pesticide mixtures.

Environmental Toxicology and Chemistry↗

USGS2015

An evaluation of the residual toxicity and chemistry of a sodium hydroxide-based ballast water treatment system for freshwater ships

Nonnative organisms in the ballast water of freshwater ships must be killed to prevent the spread of invasive species. The ideal ballast water treatment system (BWTS) would kill 100% of ballast water organisms with minimal residual toxicity to organisms in receiving waters. In the present study, the residual toxicity and chemistry of a BWTS was evaluated. Sodium hydroxide was added to elevate pH to >11.5 to kill ballast water organisms, then reduced to pH <9 by sparging with wet-scrubbed diesel exhaust (the source of CO 2 ). Cladocerans ( Ceriodaphnia dubia ), amphipods ( Hyalella azteca ), and fathead minnows ( Pimephales promelas ) were exposed for 2 d to BWTS water under an air atmosphere (pH drifted to ≥9) or a 2.5% CO 2 atmosphere (pH 7.5–8.2), then transferred to control water for 5 d to assess potential delayed toxicity. Chemical concentrations in the BWTS water met vessel discharge guidelines with the exception of concentrations of copper. There was little to no residual toxicity to cladocerans or fish, but the BWTS water was toxic to amphipods. Maintaining a neutral pH and diluting BWTS water by 50% eliminated toxicity to the amphipods. The toxicity of BWTS water would likely be minimal because of rapid dilution in the receiving water, with subsurface release likely preventing pH rise. This BWTS has the potential to become a viable method for treating ballast water released into freshwater systems.

Environmental Toxicology and Chemistry↗

USGS2015

The Penobscot River and environmental contaminants: Assessment of tribal exposure through sustenance lifeways

EPA in collaboration with the Penobscot Indian Nation, U.S. Geological Survey (USGS), Agency for Toxic Substances and Disease Registry (ATSDR), and the U.S. Fish and Wildlife Service (USF&WS) collectively embarked on a four year research study to evaluate the environmental health of the riverine system by targeting specific cultural practices and using traditional science to conduct a preliminary contaminant screening of the flora and fauna of the Penobscot River ecosystem. This study was designed as a preliminary screening to determine if contaminant concentrations in fish, eel, snapping turtle, wood ducks, and plants in Regions of the Penobscot River relevant to where PIN tribal members hunt, fish and gather plants were high enough to be a health concern. This study was not designed to be a statistically validated assessment of contaminant differences among study sites or among species. The traditional methodology for health risk assessment used by the U. S. Environmental Protection Agency (EPA) is based on the use of exposure assumptions (e.g. exposure duration, food ingestion rate, body weight, etc.) that represent the entire American population, either as a central tendency exposure (e.g. average, median) or as a reasonable maximum exposure (e.g. 95% upper confidence limit). Unfortunately, EPA lacked exposure information for assessing health risks for New England regional tribes sustaining a tribal subsistence way of life. As a riverine tribe, the Penobscot culture and traditions are inextricably tied to the Penobscot River watershed. It is through hunting, fishing, trapping, gathering and making baskets, pottery, moccasins, birch-bark canoes and other traditional practices that the Penobscot culture and people are sustained. The Penobscot River receives a variety of pollutant discharges leaving the Penobscot Indian Nation (PIN) questioning the ecological health and water quality of the river and how this may affect the practices that sustain their way of life. The objectives of this Regional Applied Research Effort (RARE) study were to: Develop culturally sensitive methodologies for assessing the potential level of exposure tocontaminants that Penobscot Indian Nation tribal members may have from maintainingtribal sustenance practices. Conduct field surveys and laboratory analysis on targeted flora and fauna for chemicalexposure to dioxins/furans, polychlorinated biphenyls (PCBs), total mercury and methyl-mercury. Assist the Agency for Toxic Substances and Disease Registry (ATSDR) by providing thenecessary data to conduct a Public Health Assessment for the Penobscot Indian Nation. Establish protocols for assessing the level of exposure to PCBs, dioxins/furans and mercuryto PIN tribal members as a consequence of gathering tribal plants for medicinal andnutritional purposes; as well as consuming fish, wood duck, and snapping turtle as a primarysource of nutrition. Survey surface water, drinking water, and sediment from the Penobscot River and IndianIsland to assess the exposure of PIN tribal members to environmental genotoxicants thatcontinue cultural sustenance practices. This research initiative collected and analyzed sediment and biota to determine the level of contaminant exposure to Penobscot tribal members. Natural resource utilization patterns and exposure pathways were identified based on discussions with the Tribal elders. Identification of Tribal exposure factors (exposure pathways and contaminant concentrations) was essential for accurately assessing potential long-term Penobscot Indian Nation tribal members’ exposure. Based on this study, ATSDR’s Public Health Assessment (PHA) concluded that the Penobscot Indian Nation (PIN) tribal members who eat fish and snapping turtle at the ingestion levels suggested in the Wabanaki Traditional Cultural Lifeways Exposure Scenario Report (Wabanaki Exposure Scenario) may be exposed to harmful levels of mercury, dioxins/furans, dioxin-like PCBs, and ot

Maine↗

USGS2012

Mercury bioaccumulation in wood frogs developing in seasonal pools

Seasonal woodland pools contribute significant biomass to terrestrial ecosystems through production of pool-breeding amphibians. The movement of amphibian metamorphs potentially transports toxins bioaccumulated during larval development in the natal pool into the surrounding terrestrial environment. We documented total mercury (THg) in seasonal woodland pool water, sediment, litter, and Lithobates sylvaticus LeConte (Wood Frog) in Acadia National Park, ME. THg concentrations in pool water varied over the study season, increasing during April—June and remaining high in 2 of 4 pools upon October refill. Water in pools surrounded by softwoods had lower pH, greater dissolved organic carbon, and greater THg concentrations than pools surrounded by hardwoods, with seasonal patterns in sediment THg but not litter THg. THg increased rapidly from near or below detection in 1–2 week old embryos (<0.2 ng; 0–0.49 ppb wet weight) to 17.1–54.2 ppb in tadpoles within 6 weeks; 7.2–42.0% of THg was methyl Hg in tadpoles near metamorphosis. Metamorphs emigrating from seasonal pools may transfer mercury into terrestrial food webs.

Northeastern Naturalist↗

USGS2006

The chlorinated AHR ligand 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) promotes reactive oxygen species (ROS) production during embryonic development in the killifish ( Fundulus heteroclitus )

Exposure to dioxin-like chemicals that activate the aryl hydrocarbon receptor (AHR) can result in increased cellular and tissue production of reactive oxygen species (ROS). Little is known of these effects during early fish development. We used the fish model, Fundulus heteroclitus , to determine if the AHR ligand and pro-oxidant 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) can increase ROS production during killifish development, and to test a novel method for measuring ROS non-invasively in a living organism. The superoxide-sensitive fluorescent dye, dihydroethidium (DHE), was used to detect in ovo ROS production microscopically in developing killifish exposed to PCB126 or vehicle. Both in ovo CYP1A activity (ethoxyresorufin- o -deethylase, EROD) and in ovo ROS were induced by PCB126. In ovo CYP1A activity was inducible by PCB126 concentrations as low as 0.003 nM, with maximal induction occurring at 0.3 nM PCB126. These PCB126 concentrations also significantly increased in ovo ROS production in embryonic liver, ROS being detectable as early as 5 days post-fertilization. These data demonstrate that the pro-oxidant and CYP1A inducer, PCB126, increases both CYP1A activity and ROS production in developing killifish embryos. The superoxide detection assay (SoDA) described in this paper provides a semi-quantitative, easily measured, early indicator of altered ROS production that can be used in conjunction with simultaneous in ovo measurements of CYP1A activity and embryo development to explore functional relationships among biochemical, physiological and developmental responses to AHR ligands.

Aquatic Toxicology↗