Download or read book Comparing the Mercury Contamination of Fish Tissue Samples in Palm Beach County Broward County and Miami Dade County written by Mirelle Dawoud and published by . This book was released on 2014 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Humans are most prevalently exposed to mercury through the consumption of fish, which are exposed to mercury in water through local and global pollution. Local point sources for pollution are sewage sludge exposed to the atmosphere in water treatment facilities and landfills. In this study, 17 fish tissue samples were analyzed from 5 collection sites in Southeastern Florida. I compared three counties, Palm Beach, Broward, and Miami Dade, in order to correlate the amounts of contamination to local point source pollution proximity. Analysis of the tissue samples was performed at Jupiter Environmental Laboratories Incorporated using a PSA 10.025 Millennium Merlin mercury analyzer according to the standards of EPA 1631. The data collected from the analyzed specimen demonstrated that Miami Dade had lower increases in bioaccumulation. The samples collected in Palm Beach County and Broward County were fairly homogenous and did not show statistical significance for proximity to local point source pollution.

Download or read book Mercury in Fish Bed Sediment and Water from Streams Across the United States 1998 2005 written by Barbara C. Scudder and published by DIANE Publishing. This book was released on 2010-08 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: Report on how mercury (Hg) was examined in top-predator fish, bed sediment, and water from streams that spanned regional and national gradients of Hg source strength and other factors thought to influence methylmercury bioaccum. Sampled settings include stream basins that were agr¿l, urbanized, undeveloped, and mined. Predator fish were targeted for collection, and composited samples of fish were analyzed for total Hg (THg), as most of the Hg found in fish tissue is MeHg. Samples of bed sediment and stream water were analyzed for THg, MeHg, and characteristics thought to affect Hg methylation, such as loss-on-ignition and acid-volatile sulfide in bed sediment, and pH, dissolved organic carbon, and dissolved sulfate in water. Illus.

Download or read book Mercury Contamination and Its Relation to Trophic Ecology and Anthropogenic Pollution in Coastal and Deep Sea Shark Communities written by Johanna Leigh Imhoff and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of changing anthropogenic mercury emissions on marine wildlife is of broad interest. Methylmercury can cause reproductive and neurological damage and biomagnifies in food webs. Mercury availability in the Pacific Ocean has been increasing and therefore could be expected to increase in marine fishes. In Hawaii, tunas have shown increases proportional to increasing oceanic mercury over several decades. Historical data on shark muscle mercury is also available for Hawaii, presenting an opportunity for comparison in a long-lived upper trophic level cartilaginous fish. Muscle samples were opportunistically collected from sandbar sharks in 2003-2005 for mercury analysis and comparison with published data from 1971. Mercury contamination was similar in sandbar sharks collected in the two time periods, in contrast to tunas. Sandbar sharks collected in 2003-2005 had a higher observed rate of stillborn embryos than previously documented. Since mercury can cause reproductive toxicity, muscle mercury contamination was quantified in available sandbar shark embryos. Contamination was similar in stillborn and viable embryos, indicating that mercury toxicity was likely not the cause of embryo death. Mercury does not appear to have changed in sandbar sharks and the observed frequency of stillborn sharks does not appear to be due to increasing mercury emissions over three decades. Deep sea chondricthyans comprise nearly half of global chondrichthyan fauna but have been researched relatively less than their coastal and pelagic counterparts. As long-lived mesopredators and apex predators in their food webs, deep sea shark can bioaccumulate high levels of mercury in their tissues. Mercury was measured in six species of relatively abundant deep sea sharks in the GOM that inhabit the continental shelf edge to the continental slope. To attempt to address whether the Deepwater Horizon oil spill indirectly affected bioavailability of methylmercury in GOM, the same or closely related species were also analyzed from regions not affected by the oil spill. Overall, Mustelus sinusmexicanus had the lowest mercury among the GOM sharks analyzed, and Squalus clarkae had the highest. The remaining four species were similar to one another in their mercury contamination. Regional comparisons revealed similar contamination between M. canis canis in the GOM and M. canis insularis in Eleuthera. Eleuthera S. cubensis had similar mercury contamination to GOM S. clarkae, to which they were closer in size than GOM S. cubensis. GOM Centrophorus granulosus had higher mercury contamination than Virginia C. granulosus but this was only marginally significant. There was a slight and non-significant increase in mercury with depth in the GOM. M. canis caught on the east side of De Soto Canyon had significantly higher mercury than those caught on the west side of De Soto Canyon. The opposite pattern was seen in C. uyato, with higher mercury concentrations on the west side of the canyon, but these results may be strongly influenced by sample size for both species. Since mercury bioaccumulation in organisms is tightly linked to biomagnification, mercury studies are often coupled with trophic ecology studies using light stable isotopes as tracers. Since animals vary in the quantity of lipids that they store in their tissues, and since the presence of lipids can affect [delta]13C signatures, it is necessary to explore these effects to correctly interpret [delta]13C results. A particular challenge for chondrichthyan fishes is that they store isotopically light nitrogenous wastes in their tissues for osmoregulation, and this can affect the interpretation of [delta]15N, sometimes leading to inaccurate interpretation of trophic level. The effects of lipids and nitrogenous wastes on stable isotope analysis of chondrichthyan fishes has been an important aspect of trophic ecology research on this group. The effects of lipid extraction, urea extraction, and combined lipid and urea extraction compared to bulk tissue were tested on a coastal and deep sea teleost and a coastal and deep sea elasmobranch as representatives that might be included in coast to deep sea food web studies. Since mercury analysis requires the same initial muscle tissue handling steps as stable isotope analysis (SIA), the effects of treatments on mercury quantification were also tested. The results suggest that chemical lipid extraction is necessary for accurate interpretation of SIA results in coastal and deep sea teleosts and elasmobranchs and that urea was extracted sufficiently during the lipid extraction, therefore additional urea extraction steps are not necessary. Additionally, it may be possible for researchers to use leftover treated muscle from SIA to obtain accurate mercury results. Future research on trophic ecology including SIA informed by this research may help to provide context for mercury findings in GOM deep sea sharks.

Download or read book Mercury Bioaccumulation in Fish in a Region Affected by Historic Gold Mining written by and published by . This book was released on 2000 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Levels in Five Species of Commercially Important Pelagic Fish Taken from the Pacific Ocean Near Hawaii written by James Ray Thieleke and published by . This book was released on 1973 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Contamination in the Northeastern United States written by Hannah Abigail Shayler and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury contamination poses a known threat to human health, yet the degree of contamination and resulting human exposure remains unknown in many regions. Assessments of the relative risks of fish consumption are fundamentally limited by the availability of data characterizing fish consumption behaviors in a given region and the mercury concentrations in fish consumed by humans, as well as by a lack of scientific consensus about how a given level of mercury exposure is likely to affect a particular fish consumer. Existing mercury data and research findings are often not accessible to fish consumers or communicated clearly and consistently. This thesis integrates two related, yet distinct, perspectives regarding how the availability of scientific information affects decision making about the consumption of mercurycontaminated fish through a focused study of the fish consumption and mercury exposure of one community of Adirondack anglers, as well as through a broader consideration of how data collection efforts can best provide information to protect human health. This effort had two overall goals: (1) to characterize how the collection, interpretation, and communication of mercury data influence the availability and clarity of information for decision making about fish consumption; and (2) to recommend how data collection, risk assessment, and risk communication efforts can foster informed, science-based decision making about fish consumption. The first part of this research effort builds upon ongoing assessments of mercury contamination by integrating available local, regional, and national fish mercury datasets with participant consumption records to estimate the mercury exposure of fish consumers (N=17), particularly anglers and families consuming fish species sport-caught from privately owned fishing preserves in the Adirondack region. We compared exposure estimates to measured mercury concentrations in participant hair samples and to recommended health guidelines. The estimated mercury exposure of 35% of participants exceeded the USEPA reference dose for methylmercury; 35% of measured hair mercury concentrations exceeded recommended levels, and the estimated mercury exposure and measured hair mercury concentrations of 29% of participants exceeded both guidelines. Fifty years of angling catch records showed a noticeable decrease in the percentage of the total catch kept for consumption rather than caught and released; this change in angling behavior is estimated to have reduced the mean mercury exposure of our study community from preserve sport-caught fish (e.g., from the waters of private Adirondack fishing preserves alone) by 84%. In the second part of this thesis, we review recent efforts to collect and integrate fish mercury data in the northeastern United States, a region that is particularly influenced by atmospheric deposition of mercury, and provide suggestions to improve and focus future research and monitoring efforts to better address threats to human health. Resource and sampling limitations have hindered comprehensive understanding of mercury in the environment and relative levels of methylmercury exposure through fish consumption. Because of these limitations, data collection should maximize the benefits of information gained by monitoring programs. By selecting appropriate target species - those species and sizes of fish harvested for consumption and those with the highest and most variable mercury concentrations at a given location - health and fisheries professionals can more comprehensively advise fish consumers and inform the protection of human health. Overall, the findings from this study will inform our understanding of: (1) how the availability and clarity of mercury information influence decision making about fish consumption, and (2) how a more comprehensive approach to data collection can more clearly characterize the relative risks to anglers and their families and thereby foster informed, science-based decision making about fish consumption.

Download or read book A Comparison of Two Analytical Methods for Measuring Mercury in Fish Tissue written by Chad Furl and published by . This book was released on 2007 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Contamination in Fish from Northern California Lakes and Reservoirs written by California. Department of Water Resources. Northern District and published by . This book was released on 2007 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Contaminant Study of Louisiana written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This Louisiana Dept. of Environmental Quality (LDEQ) page provides data on mercury contamination of water bodies within the state, as well as information about the human health risks associated with eating mercury-contaminated fish. Data is from tissue samples of fish caught all around the state. Mercury concentrations are measured in parts per million (ppm) and the data files are updated weekly. Contents: Summary of issues related to mercury contamination of fish -- Fish consumption and swimming advisories -- Data files (Table of site locations and site specific data ; Summary of concentration/maximum by site ; Summary of concentration/maximum by species ; Raw data updated weekly) -- Map of site locations and site specific data.

Download or read book Mercury Concentrations in Fish Tissues from Sapphire Lake Golden Gate City Canal System and Faka Union Canal November 1989 written by Collier County Environmental Services Division. Pollution Control Department and published by . This book was released on 1990 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Largemounth Bass and Water Quality written by FL). STATE OF FLORIDA. Departament of Environmental Regulation (St. Petersburg and published by . This book was released on 1990 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information and issues; Summary of findings; Limitations of analysis; Discussion; Data base analysis; Game and fresh water fish commission mercury data; Range of mercury concentrations in largemouth bass tissue; Spatial distribution of mercury data in Florida; Statewide distribution of mercury in largemouth bass tissue; Mercury concentration in Florida lakes; Mercury concentration in Florida streams; Appendix.

Download or read book Determination of Mercury in Fish Tissue Part I written by D. E. King and published by . This book was released on 1992 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review was initiated to determine whether performance criteria could be set for contract laboratory analysis of mercury in fish. In the early 1970s, a series of round-robin studies using samples of canned fish prepared for the purpose was initiated. These studies continued on a regular 4-month basis for the past 20 years, with 20-30 participants in the last few years. Each analyst is requested to provide triplicate measurements on two different days for each of four different samples. Laboratories participate on a voluntary basis and are not identified by name in the study reports. This review summarizes the performance of only those laboratories which provided results for each of 32 samples, submitted in eight sets of four samples each, between July 1987 and June 1991, to examine the possibility for setting performance criteria.

Download or read book Toxicological Effects of Methylmercury written by National Research Council and published by National Academies Press. This book was released on 2000-10-27 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury is widespread in our environment. Methylmercury, one organic form of mercury, can accumulate up the aquatic food chain and lead to high concentrations in predatory fish. When consumed by humans, contaminated fish represent a public health risk. Combustion processes, especially coal-fired power plants, are major sources of mercury contamination in the environment. The U.S. Environmental Protection Agency (EPA) is considering regulating mercury emissions from those plants. Toxicological Effects of Methylmercury reviews the health effects of methylmercury and discusses the estimation of mercury exposure from measured biomarkers, how differences between individuals affect mercury toxicity, and appropriate statistical methods for analysis of the data and thoroughly compares the epidemiological studies available on methylmercury. Included are discussions of current mercury levels on public health and a delineation of the scientific aspects and policy decisions involved in the regulation of mercury. This report is a valuable resource for individuals interested in the public health effects and regulation of mercury. The report also provides an excellent example of the implications of decisions in the risk assessment process for a larger audience.

Download or read book A Preliminary Investigation of Mercury Contamination in the Fish and Wildlife of Cumberland County written by Gerald D. Seiler and published by . This book was released on 1971 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mercury Concentrations in Water and Mercury and Selenium Concentrations in Fish from Brownlee Reservoir and Selected Sites in Boise and Snake Rivers Idaho and Oregon 2013 written by Dorene E. MacCoy and published by . This book was released on 2014 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury (Hg) analyses were conducted on samples of sport fish and water collected from six sampling sites in the Boise and Snake Rivers, and Brownlee Reservoir to meet National Pollution Discharge and Elimination System (NPDES) permit requirements for the City of Boise, Idaho. A water sample was collected from each site during October and November 2013 by the City of Boise personnel and was analyzed by the Boise City Public Works Water Quality Laboratory. Total Hg concentrations in unfiltered water samples ranged from 0.73 to 1.21 nanograms per liter (ng/L) at five river sites; total Hg concentration was highest (8.78 ng/L) in a water sample from Brownlee Reservoir. All Hg concentrations in water samples were less than the EPA Hg chronic aquatic life criterion in Idaho (12 ng/L). The EPA recommended a water-quality criterion of 0.30 milligrams per kilogram (mg/kg) methylmercury (MeHg) expressed as a fish-tissue residue value (wet-weight MeHg in fish tissue). MeHg residue in fish tissue is considered to be equivalent to total Hg in fish muscle tissue and is referred to as Hg in this report. The Idaho Department of Environmental Quality adopted the EPA's fish-tissue criterion and a reasonable potential to exceed (RPTE) threshold 20 percent lower than the criterion or greater than 0.24 mg/kg based on an average concentration of 10 fish from a receiving waterbody. NPDES permitted discharge to waters with fish having Hg concentrations exceeding 0.24 mg/kg are said to have a reasonable potential to exceed the water-quality criterion and thus are subject to additional permit obligations, such as requirements for increased monitoring and the development of a Hg minimization plan. The Idaho Fish Consumption Advisory Program (IFCAP) issues fish advisories to protect general and sensitive populations of fish consumers and has developed an action level of 0.22 mg/kg wet weight Hg in fish tissue. Fish consumption advisories are water body- and species-specific and are used to advise of allowable fish consumption from specific water bodies. The geometric mean Hg concentration of 10 fish of a single species collected from a single water body (lake or stream) in Idaho is compared to the action level to determine if a fish consumption advisory should be issued. The U.S. Geological Survey collected and analyzed individual fillets of mountain whitefish (Prosopium williamsoni), smallmouth bass (Micropterus dolomieu), and channel catfish (Ictalurus punctatus) for Hg. The median Hg concentration of 0.32 mg/kg exceeded the Idaho water-quality criterion at the site in Brownlee Reservoir. Average Hg concentrations from Brownlee Reservoir (0.32 mg/kg) and the Boise River at mouth (0.33 mg/kg) exceeded the Hg RPTE threshold (>0.24 mg/kg). IFCAP action levels also were exceeded at the sites on Brownlee Reservoir and at the mouth of the Boise River. Median Hg concentrations in fish at the remaining four river sites were less than 0.20 mg/kg with average concentrations ranging from 0.14 to 0.21 mg/kg Hg. Selenium (Se) analysis also was conducted on one composite fish tissue sample per site to screen for general concentrations and to provide information for future risk assessments. Concentrations of Se ranged from 0.07 to 0.49 mg/kg wet weight; average concentrations were highest in smallmouth bass (0.40 mg/kg) and lowest in mountain whitefish (0.12 mg/kg).

Download or read book Conference in the Matter of Pollution of the Navigable Waters of Dade County Florida and Tributaries Embayments and Coastal Waters written by Conference in the Matter of Pollution of the Navigable Waters of Dade County, Florida [etc.] and published by . This book was released on 1970 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of a Statistical Model based Prediction of Mercury Concentrations in Ontario Sport Fish written by Eric James DeLong and published by . This book was released on 2012 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the mid-1970s, the Ontario (Canada) Ministry of Environment (OMOE) has been collecting data on fish tissue mercury (Hg) contamination in provincial waterbodies. By 2004, approximately 160,000 fish from 86 species at over 1,600 sites were tested for Hg. This large database is primarily used to issue advisories for safe human fish consumption via publication of the biennial Guide to Eating Ontario Sport Fish. Analysis to uncover spatio-temporal trends while maximising the use of data points is complicated by the application of a non-random heterogeneous sampling design. The National Descriptive Model for Mercury in Fish (NDMMF) developed by the United States Geological Survey (USGS) is a statistical model of Hg concentrations that can potentially mitigate these challenges by separating the spatiotemporal variability of fish-[Hg] sampling while considering the effects of species, size, and fish sample portion type. However, the NDMMF has not been fully exploited, likely due to lack of rigorous evaluation. We conduct the first detailed investigation on the ability of the NDMMF to reproduce the observed fish-[Hg] in coolwater walleye (Sander vitreous) and warm-water yellow perch (Perca flavescens). Approximately two-thirds of both walleye and yellow perch [Hg]-length relationships could be accurately predicted using the NDMMF. For these cases, a majority (>85%) of the estimates are within the same consumption advisory categories as the interpolated [Hg] value based on the observed data, using an average-length fish. For the remaining incidences with significantly different NDMMF fish [Hg]-length relationships compared to those from the observed data, the NDMMF notably yields similar results, with a majority (>75%) of [Hg] estimates still falling within the same consumption advisory categories. For the small fraction of incidences with inaccurate advisory categorization, the instances of conservative over-prediction (