Fish Advisories: Useful Or Difficult to Interpret?

The authors note that fish and shellfish offer significant exposure to environmental toxins but find that consumer knowledge and other factors may limit efforts to control risk in urban populations

Comparison of Indoor Mercury Vapor in Common Areas of Residential Buildings with Outdoor Levels in a Community Where Mercury Is Used for Cultural Purposes

Elemental mercury has been imbued with magical properties for millennia, and various cultures use elemental mercury in a variety of superstitious and cultural practices, raising health concerns for users and residents in buildings where it is used. As a first step in assessing this phenomenon, we compared mercury vapor concentration in common areas of residential buildings versus outdoor air, in two New Jersey cities where mercury is available and is used in cultural practices. We measured mercury using a portable atomic absorption spectrometer capable of quantitative measurement from 2 ng/m(3) mercury vapor. We evaluated the interior hallways in 34 multifamily buildings and the vestibule in an additional 33 buildings. Outdoor mercury vapor averaged 5 ng/m(3); indoor mercury was significantly higher (mean 25 ng/m(3); p < 0.001); 21% of buildings had mean mercury vapor concentration in hallways that exceeded the 95th percentile of outdoor mercury vapor concentration (17 ng/m(3)), whereas 35% of buildings had a maximum mercury vapor concentration that exceeded the 95th percentile of outdoor mercury concentration. The highest indoor average mercury vapor concentration was 299 ng/m(3), and the maximum point concentration was 2,022 ng/m(3). In some instances, we were able to locate the source, but we could not specifically attribute the elevated levels of mercury vapor to cultural use or other specific mercury releases. However, these findings provide sufficient evidence of indoor mercury source(s) to warrant further investigation

DNA Double-Strand Breakage as an Endpoint to Examine Metal and Radionuclide Exposure Effects to Water Snakes on a Nuclear Industrial Site

This study examined metal levels (especially U and Ni) in the tail tissues of water snakes from contaminated (Tim’s Branch) and reference areas on the Department of Energy’s Savannah River Site (SRS). Home ranges of snakes were quantified to determine the ratio of the habitat that they use in relation to the contaminated areas to better estimate exposure Compared to conventional methods that do not. The exposure assessment indicated that water snakes in the contaminated areas could expect U exposure at 3–4 orders of magnitude greater than the Agency for Toxic Substances and Disease Registry’sMinimum Risk Level (MRL) from ingestion of amphibians and fish. Ni and U, in addition to Se, Mn, and Cu, were related to increased DNA double-strand breakage (DDSB) in water snakes.We report burdens for each metal individually, but the results of the DDSB indicated that these metals did not behave independently, but as a suite. If we did not have a secondary endpoint (DDSB), we might have assumed from the exposure predictions and tissue burden analyses that U was the sole metal of concern to water snakes in Tim’s Branch. These data also imply that these toxicants do not biomagnify at the spatial and temporal scale of this study

Microbiome diversity and metabolic capacity determines the trophic ecology of the holobiont in Caribbean sponges

Sponges are increasingly recognized as an ecologically important taxon on coral reefs, representing significant biomass and biodiversity where sponges have replaced scleractinian corals. Most sponge species can be divided into two symbiotic states based on symbiont community structure and abundance (i.e., the microbiome), and are characterized as high microbial abundance (HMA) or low microbial abundance (LMA) sponges. Across the Caribbean, sponge species of the HMA or LMA symbiotic states differ in metabolic capacity, as well as their trophic ecology. A metagenetic analysis of symbiont 16 S rRNA and metagenomes showed that HMA sponge microbiomes are more functionally diverse than LMA microbiomes, offer greater metabolic functional capacity and redundancy, and encode for the biosynthesis of secondary metabolites. Stable isotope analyses showed that HMA and LMA sponges primarily consume dissolved organic matter (DOM) derived from external autotrophic sources, or live particulate organic matter (POM) in the form of bacterioplankton, respectively, resulting in a low degree of resource competition between these symbiont states. As many coral reefs have undergone phase shifts from coral- to macroalgal-dominated reefs, the role of DOM, and the potential for future declines in POM due to decreased picoplankton productivity, may result in an increased abundance of chemically defended HMA sponges on tropical coral reefs

Using Raccoons as an Indicator Species for Metal Accumulation Across Trophic Accumulation across Trophic Levels: A Stable Isotope Approach

: The fact that raccoons (Procyon lotor) are an opportunistic omnivore has severely complicated interpreta- tions of contaminant uptake patterns due to the inability to determine the trophic position an individual occupies. Moreover, few studies have examined the relationships between heavy metal bioaccumulation and trophic struc- ture, especially in the terrestrial environment. In this study, the stable isotopes of nitrogen were used to charac- terize the feeding habits of the raccoon at the population level and to determine whether metal burden was relat- ed to trophic feeding structure within a welldefined ecosystem. Raccoon populations were isotopically distinct, and significant positive relationships existed between some trace element contents and 6 1 5 ~of muscle when site was used as a covariable in a statistical model. Although the transfer of metals through terrestrial ecosystems is com- plex, our study showed that some of the variation in contaminant body burdens in raccoon populations can be attributed to trophic feeding position and that 1 5 ~ / 1 4 ~ ratios of muscle tissue provide a quantitative measure of this process. The potential for using omnivores such as the raccoon, as a sentinel species for contaminant studies, should be explored further since the ambiguity of the relative trophlc level an animal occupies can be directly esti- mated. This provides a more extensive sampling across trophic levels using a single species, which can have broad consequences for ecological risk assessment

Raccoons as potential vectors of radionuclide contamination to human food chains from a nuclear industrial site

Although the raccoon (Procyon lotor) is commonly harvested and consumed throughout the southeastern United States, little is known regarding the fate and effects of environmental pollutants to this species, and the potential for it to act as a contaminant vector to humans or other predators. Muscle and liver tissues were collected from 76 raccoons from locations on and near the Department of Energy\u27s Savannah River Site (SRS) in South Carolina and analyzed for radiocesium (137Cs). Raccoons were trapped from areas near a former reactor cooling reservoir known to be contaminated from former nuclear production activities, a stream drainage system also known to have received 137Cs contamination from low level releases, and 4 on-site reference areas that have been unimpacted by nuclear production activities. Raccoons from 3 hunting areas 3-15 km of SRS were used as off-site reference samples. 137Cs levels differed between the 3 treatment groups (contaminated, on-site reference, off-site reference) for both muscle and liver tissues. Muscle and liver samples from raccoons from on-site reference areas were higher in 137Cs than those from off-site reference animals. 137Cs in raccoon tissues from contaminated habitats exceeded levels in the pooled reference animals. The 2 contaminated areas differed in 137Cs tissue levels. Only 1 of 20 raccoons from contaminated sites on the SRS exceeded the European Economic Community (EEC) limit for 137Cs in edible muscle tissue of 0.6 Bq 137Cs/g fresh-weight edible muscle. Further, none of the raccoons from the on-site reference areas exceeded EEC limits for muscle. It is unlikely that the hunting public faces any significant risk from exposure to raccoons from the SRS. Although some raccoons might stray off the SRS which is closed to public access, most of the heavily contaminated areas are not adjacent to the edges of the site, decreasing the potential for off-site movement of contaminated animals

Attitudes and perceptions about ecological resources and hazards of people living around the Savannah River Site

Although considerable attention is devoted to environmental monitoring and assessment with respect to both pollutants and the status of particular plant or animal populations, less attention is devoted to assessing people\u27s attitudes about the relative importance of ecological resources. In this paper we examine the attitudes and perceptions about ecological resources of people living around the Department of Energy\u27s Savannah River Site (SRS), in South Carolina. Our overall hypothesis is that people who are directly affected by the possible outcomes and consequences of a particular hazard (i.e., those people employed at SRS) will undervalue the risks and overvalue the potential benefits from future land uses that favour continued site activity, compared to people who live near but are not employed at SRS. We interviewed 286 people attending the Aiken Trials horse show on 14 March 1997. There were few gender differences, although men hunted and fished more than women, women ranked three environmental concerns as more severe than did men, and women were more concerned about the effect of SRS on property values. Maintenance of SRS as a National Environmental Research Park ranked first as a future land use; nuclear production ranked second, followed by hunting and hiking. Only residential development ranked very low as a future land use. There were many differences as a function of employment history at SRS: (1) people who work at SRS think that the federal government should spend funds to clean up all nuclear facilities, and they think less money should be spent on other environmental problems than did non-employees, (2) people who work at SRS ranked continued current uses of SRS higher than did people who never worked at SRS, and (3) people who work at SRS are less concerned about the storage of nuclear material or accidents at the site than are people who never worked at the site

Attitudes and perceptions about ecological resources and hazards of people living around the Savannah River Site

Although considerable attention is devoted to environmental monitoring and assessment with respect to both pollutants and the status of particular plant or animal populations, less attention is devoted to assessing people\u27s attitudes about the relative importance of ecological resources. In this paper we examine the attitudes and perceptions about ecological resources of people living around the Department of Energy\u27s Savannah River Site (SRS), in South Carolina. Our overall hypothesis is that people who are directly affected by the possible outcomes and consequences of a particular hazard (i.e., those people employed at SRS) will undervalue the risks and overvalue the potential benefits from future land uses that favour continued site activity, compared to people who live near but are not employed at SRS. We interviewed 286 people attending the Aiken Trials horse show on 14 March 1997. There were few gender differences, although men hunted and fished more than women, women ranked three environmental concerns as more severe than did men, and women were more concerned about the effect of SRS on property values. Maintenance of SRS as a National Environmental Research Park ranked first as a future land use; nuclear production ranked second, followed by hunting and hiking. Only residential development ranked very low as a future land use. There were many differences as a function of employment history at SRS: (1) people who work at SRS think that the federal government should spend funds to clean up all nuclear facilities, and they think less money should be spent on other environmental problems than did non-employees, (2) people who work at SRS ranked continued current uses of SRS higher than did people who never worked at SRS, and (3) people who work at SRS are less concerned about the storage of nuclear material or accidents at the site than are people who never worked at the site