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J Burger

Publications and source records attributed to J Burger.

At least 19 recordsLinked to original sources

Environmental attitudes and perceptions of future land use at the Savannah River Site: are there racial differences?

People make subjective judgments about the severity of environmental problems and on future land use relying on certain information, and on their experiences with the problem. This article examines perceptions of the severity of environmental problems, willingness to expend future funds to solve these problems, and future land use for the Department of Energy's Savannah River Site (SRS) in South Carolina as a function of race. The null hypothesis that there are no racial differences in perceptions was tested. Of those interviewed, 23% of the 399 people were black, 75% were white, and 2% identified themselves as other. Blacks were significantly more willing than whites to spend federal funds to solve environmental problems such as cleaning up the SRS and Superfund sites, fixing ozone depletion, and reducing the threats from radon and high-tension power lines. There were statistically significant racial differences in preferences for future land use at the SRS, with blacks having a higher preference for using it as a preserve, and whites having a higher preference for a research park, camping, hiking, and hunting. These results indicate that the environmental concerns of the blacks interviewed were equal to or stronger than those of the whites. This is in contrast to much of previously published work that shows that blacks exhibit lower concerns and actions than whites for environmental problems.

Attitude

Gender differences in attitudes about fish safety in a coastal population.

Behavioral approaches to reducing the adverse health effects of consuming fish with high contaminant levels benefit from understanding attitudes and perceptions about the relative safety of fish. Gender differences in attitudes about fish safety were investigated by interviewing 197 men and 94 women who attended a Duck Decoy show at Tuckerton, NJ. There were significant gender differences in perceptions of the safety of fish, ducks, and deer, with women generally believing that it was less safe to eat these foods than did men. Although people correctly perceived that ocean fish were safer than bay-caught fish from a chemical contaminant perspective, perceptions were less clear with respect to consuming predatory or herbivorous, or large versus small fish. Although men significantly perceived small fish as safer than large fish, women did not. However, people correctly believed that bluefish (a predaceous fish) were less safe than flounder (an herbivore). People uniformly believed it was safer to eat fish they caught themselves or bought in a fish store than those from a supermarket. These results suggest that any program to inform the public about the potential dangers from contaminated fish should take into account gender differences in perceptions.

Animals

Temporal trends in metal levels in eggs of the endangered roseate tern (Sterna dougallii) in New York.

Female birds sequester certain organic and inorganic compounds in their eggs which have been widely used as a bioindicator for examining the body burdens of contaminants and therefore the temporal and spatial trends of the contaminants in the environment. The same analyses can also reflect the status or vulnerability of the indicator species. Extensive bridge de-leading activities in the New York Bight (Cape May to Montauk) in the early 1990s coincided with a long-term study of the endangered roseate tern (Sterna dougallii) on Long Island, New York, affording the opportunity to test the utility of such fish-eating species as bioindicators of lead contamination, as well as the potential impact on the bird population itself. In this paper we test the null hypothesis that there were no temporal trends between 1989 and 1994 in metal levels in eggs of roseate terns nesting at Cedar Beach, Long Island, where the birds have been declining since the late 1980s. We report levels and trends for cadmium, chromium, manganese, mercury, and selenium as well as lead in abandoned eggs collected each year. There were significant interyear differences for all metals, with 1990 to 1992 generally having higher levels than 1989 and 1994. The yearly differences were particularly prominent for lead, where the 10-fold increase may have been partially due to the increased removal of leaded paint from bridges in the early 1990s, leading to increased lead in the aquatic environment. Cadmium and chromium are also released during de-leading. The causes for the higher levels in the other metals in the early 1990s are unclear. Metal levels in roseate tern eggs are several times higher than the median reported for most birds, and the possible impact on the population requires study.

Animals

Fishing, consumption, and risk perception in fisherfolk along an east coast estuary.

Increasingly public and governmental agencies are concerned about the safety of fish and shellfish that recreational fishermen consume. Fishing behavior, consumption patterns, and risk perceptions were examined for people flashing and crabbing in Barnegat Bay, NJ. Women fished in significantly larger groups than men, and their groups included more children. Subjects fished an average of seven times per month and crabbed three times per month; they caught fish on most outings, and 80% ate their catch. Subjects consumed fish an average of five times a month, eating just under 10 oz (ca. 280 g) per meal. Only 25% of the fish consumed by women, and 49% of the fish consumed by men, are self-caught. Nearly 90% of the people believe the fish and crabs from Barnegat Bay are safe to eat, although about 40% have heard some warnings about their safety. Most people heard about advisories from newspapers or television. Most subjects believe that saltwater fish are safer than freshwater fish and that fish they catch themselves or buy in a bay store are safer than those from a supermarket. People generally do not have a clear understanding of the relationship between contaminants and fish size or trophic level, suggesting an avenue for risk reduction.

Adolescent

Effects of lead on sibling recognition in young herring gulls.

Lead exposure early in life affects physiology, behavior, and cognitive development in humans and other animals. In gulls, lead also disrupts parental recognition, leading to potential decreases in survival in wild populations. In this paper, young herring gulls, Larus argentatus, were used to examine the effect of lead on sibling recognition. Each of 80 one-day-old herring gull chicks was randomly assigned to either a control group or a lead treatment group that received a single dose of lead acetate solution (100 mg/kg) at day 2. Matched controls were injected with isotonic saline at the same age. At 10 days of age, there was no demonstrable sibling recognition in control chicks, but recognition was clearly developed by 15 days of age. Lead disrupted sibling recognition, and there still was no evidence of sibling recognition in lead-injected chicks by 26 days of age. Time to respond initially increased and then decreased with age in both control and lead-injected chicks. Control chicks that correctly reached their siblings did so in significantly less time than did lead-injected chicks, and they remained closer to their siblings at the end of the test. These experiments clearly demonstrate that lead disrupts sibling recognition in herring gull chicks, delays the time to respond and to reach their siblings, and increases the final distance chicks are from their calling siblings. In nature, lead-impaired chicks would be unable to use siblings as a cue enabling them to find their nests and might suffer higher mortality from territorial adults and chicks, as well as from cannibalistic adults.

Animals

Trace elements in egg contents and egg shells of slider turtles (Trachemys scripta) from the Savannah River Site.

In this paper we examine the levels of trace elements in the egg contents and egg shells of slider turtles (Trachemys scripta) from the Savannah River Site, near Aiken, South Carolina. Trace elements have seldom been examined in the tissues or eggs of reptiles, although some turtles and large snakes occupy a high trophic level. Lead, mercury, cadmium, selenium, chromium, and manganese levels were examined in one egg and its egg shell collected from each of 16 females that laid in late May and June 1996. We were interested in determining background levels, whether certain metals were sequestered in the egg shells, and whether levels were higher in contents or shells. Concentrations were higher in egg contents than in shells for lead, mercury, and selenium, while chromium was higher in the shell. There were no differences for cadmium and manganese. Compared to eggs from other reptiles, levels in slider turtles were generally similar for cadmium and selenium, lower for chromium and lead, and higher for manganese.

Animals

Apparent paralytic shellfish poisoning in captive herring gulls fed commercial scallops.

This report describes an acute poisoning event observed in captive herring gull (Larus argentatus) chicks fed a batch of store-bought scallops. They developed a characteristic acute syndrome, that has not hitherto been reported in birds and the cause of which remains to be identified. We suggest that it is a variant of paralytic shellfish poisoning (PSP) insofar as it was paralytic and caused by shellfish. However, analyses by the U.S. Food and Drug Administration to identify known toxins (saxitoxins, brevetoxins, domoic acid) in the scallops were negative.

Animals

Plasma prostaglandin E2 concentrations after single dose administration of ketorolac tromethamine (Toradol) in dogs.

Ketorolac tromethamine (Toradol) is a relatively new, potent, non-narcotic analgesic with cyclooxygenase (COX) inhibitory activity and has been associated with gastric and renal toxicity in people and dogs. The objectives of this study were to establish whether endogenous PGE2 exists in the plasma of healthy dogs and to determine if, and to what magnitude, ketorolac alters PGE2 plasma concentrations after administration. Enzyme immunoassay measurement of a stable PGE2 derivative, bicyclo PGE2, showed that after i.v. administration of 0.5 mg/kg ketorolac tromethamine, 1 and 24 h plasma samples contained significantly (P < or = 0.01) less PGE2 than did plasma samples collected from dogs before the drug treatment. After p.o. administration, 1 h plasma samples contained significantly (P < or = 0.01) less PGE2 than did pretreatment samples, and the 24 h post-drug administration samples contained significantly (P < or = 0.01) less plasma PGE2 than the 96 h plasma samples. The results of this study suggest that a clinically effective single i.v. or p.o. dose of ketorolac tromethamine to healthy dogs causes a significant but reversible decrease in endogenous PGE2 production which may partially explain the drug's low therapeutic index.

Analysis of Variance

Paradigms for ecological risk assessment.

Ecological risk assessment developed from the convergence of human health risk assessment, ecology, and ecotoxicology to provide data for environmental management and decision making. There has been an emphasis on using the health risk paradigm. However, ecological systems are much more complex than the single-species, single-lifetime approach used in human health risk assessment; hence several modifications are necessary, as ecological risk assessment evolves for particular uses. The advancement of ecological risk assessment is particularly timely, given competing considerations for cleanup of a variety of hazardous-waste sites, including the huge Department of Defense and Department of Energy sites, as well as the 1000+ Superfund sites. Sufficient resources are not available to clean up all sites completely, much less at the same time. Some sites pose no current identifiable risk to human receptors, but may be unusable for human habitation. Where human receptors are not the targets, ecological risk assessment can be used not only to evaluate the risks to ecosystems, but to help determine the degree of cleanup required to restore degraded environments to functioning ecosystems that provide valuable ecological services, and to rank sites for possible cleanup.

Ecology

Recreation and risk: potential exposure.

The Department of Energy and other federal facilities are reclaiming land through the process of remediation and restoration, and this land will eventually be turned over for future land uses that may involve recreation. Understanding the amount of recreation that is likely (and thus individual exposure) is an essential element in decisions about cleanup standards. In this article the number of days people engage in different recreational activities as a measure of potential exposure is examined. People attending a Mayfest celebration (n = 399) and the Palmetto Sportsmen's Classic (n = 285) in Columbia, SC, were interviewed regarding their recreational activities. In most cases reported in the literature, recreational activities are examined as the mean number of days people engage in each activity per year, but to determine risk it is essential to know the distribution of these activities. In descending order of frequency, people attending the Mayfest reported their activities as birdwatching, photographing, fishing, hiking, camping, and hunting. There were significant gender differences in the frequency of activities, with men spending more days in every activity except birdwatching and photography. There were ethnic differences in recreation, with whites engaging in higher levels of most recreational activities than blacks, but the percentage of black men who reported fishing more than 100 d per year was greater than for white men. Most people reported their participation in most activities less than 30 d per year; however, a higher percentage of people reported participating in photography, birdwatching, and fishing more than 30 d per year compared to the other activities. Further, individuals at the Sportsman's Classic reported far higher rates of hunting and fishing per year than the general public. These data can be used to examine potential exposure of recreationists on remediated and restored land. The data clearly indicate that over 25% of the people engage in at least one recreational activity over 20 d per year, and thus exceed the Department of Energy's 14-d recreation assumption in its future land use document.

Cohort Studies

Attitudes toward environmental hazards: where do toxic wastes fit?

The public is continually faced with making decisions about the risks associated with environmental hazards, and, along with managers and government officials, must make informed decisions concerning possible regulation, mitigation, and restoration of degraded sites or other environmental threats. We explored the attitudes regarding several environmental hazards of six groups of people: undergraduate science majors, undergraduate nonscience majors, and graduate students in environmental health, in ecological risk assessment, and in nonscience disciplines, as well as nonstudents over 35 yr of age. We had predicted that there would be significant differences in attitudes between science and nonscience majors and as a function of age. Relative concerns could be divided into three discrete classes (in descending order of concern): (1) general ecological problems (cutting tropical forests, polluting groundwater, trash along the coasts, lead in drinking water, and acid rain), (2) radon and nuclear wastes, and finally (3) specific nuclear waste facilities, chromium, fertilizers and pesticides, and electromagnetic waves. For any hazard, attitudes were consistent across groups with regard to ranking the severity of the environmental problem and willingness to expend funds to solve the problems. Attitudes about spending money to develop methods to evaluate risk fell in the middle level of concern. There were no major differences among classes of college-age students, or between them and older nonstudents.

Adult

Risk, mercury levels, and birds: relating adverse laboratory effects to field biomonitoring.

There is an abundance of field data on levels of mercury in a variety of organisms and there are a number of studies that demonstrate the adverse effects of mercury on laboratory animals, but few studies examine the relationship between the two. Thus it is often difficult to determine the ecological relevance of mercury concentrations found in nature, or to predict the ecosystem consequences of current levels. In this paper we review the levels in tissues that are associated with adverse effects in birds from laboratory studies and compare these with levels found in wild bird populations in the New York Bight to provide a basis for interpreting values in avian populations. We use feathers from fledgling birds which would have been fed on locally obtained food to eliminate the problem of where toxic burdens were acquired by more mobile adult birds. Laboratory studies indicate that in some species mercury levels of 1.5 ppm in eggs and/or 5 to 40 ppm in the feathers of birds are associated with adverse effects, including impaired reproduction. We report egg levels in birds that range as high as 3.8 ppm and feather levels that range as high as 10.3 ppm, although means are much lower. The levels in eggs of some wild birds in the New York Bight are within the range known to lower hatchability, embryo and chick survival, and chick weight, all variables that reduce reproductive success. Species with high egg levels include Forster's tern (Sterna forsteri) and black skimmer (Rynchops niger). Levels in feathers of some young wild birds from the New York Bight are within the range associated with reduced hatchability of eggs, behavioral abnormalities of adults, and infertility. Species with dangerously elevated mercury levels in feathers include great egret (Ardea [=Egretta] alba), snowy egret [Egretta thula), and black skimmers.

Animals

Metal levels in mourning doves from South Carolina: potential hazards to doves and hunters.

Most game birds are found in lower trophic levels, but since such birds are harvested and consumed by humans, there is a particular need to assess their contaminant levels. In this paper, we report concentrations of mercury, lead, cadmium, selenium, manganese, and chromium in the breast feathers, liver, and muscle of mourning doves (Zenaida macroura) collected at a partially drawn-down, contaminated reactor-cooling reservoir (Par Pond) on the Department of Energy's Savannah River Site in South Carolina and at nearby agricultural fields managed as dove hunting areas. We test the hypothesis that the levels in doves are not harmful to either dove populations or humans. We also tested the simultaneous effects of collection location, year (1992, 1993), and dove age-class (hatch-year vs after hatch-year) on heavy metal and selenium levels. For all three tissues, mercury levels were nondetectable at all locations. Lead was highest in tissues from agricultural fields with prior histories of dove hunting activities. Doves at those fields were likely ingesting lead shot to a greater degree than at the recently drawn-down reservoir which was closed to public access and hunting. For other metals, Par Pond doves had equally high or higher tissue levels. For all metals, levels in doves from South Carolina were generally within the lower range of those reported in the literature, suggesting that these metals were likely to pose no health problems to these doves. Except for lead and selenium, metal levels in dove muscle that we observed were well below reference metal doses established for human intake. Lead and selenium, at the levels described here, would only be a problem if a child (not an adult) ate 120 g of dove meat every day of the year. Thus, we conclude that meat from these doves, if consumed by hunters, would not pose a risk.

Adult

Heavy metal and selenium concentrations in feathers of egrets from Bali and Sulawesi, Indonesia.

Herons and egrets are ideal organisms to use asindicators of heavy metal exposure in an ecosystem because different speciesfeed at different levels of the food chain and live in both coastal andinland habitats. This paper reports on the concentration of heavy metals andselenium in the feathers of cattle egrets Bubulcus ibis that wereexamined from nesting and roosting sites in Bali and Sulawesi, Indonesia, andin feathers of little egrets Egretta garzetta and intermediate egretsE. intermedia from the same colony in Bali. Mercury and manganeseconcentrations were significantly higher in cattle egrets from Bali comparedto Sulawesi, but otherwise there were no significant differences. There weresignificant differences in lead, cadmium and mercury among the three egretspecies nesting on Bali: 1) the cadmium and mercury concentrations related tosize and trophic level (insectivorous cattle egrets had the lowestconcentrations, fish-eating intermediate egrets had the highestconcentrations), and 2) cattle egrets had significantly lower concentrationsof lead than the other two species. For cattle egrets, secondary flightfeathers had significantly higher levels of cadmium and mercury, and lowerlevels of manganese, than mixed breast and tertiary feathers, reflectingtemporal differences in exposure.

Animals

Age differences in metals in the blood of herring (Larus argentatus) and Franklin's (Larus pipixcan) gulls.

Concentrations of heavy metals and selenium were measured in the blood of adult and young herring (Larus argentatus) and Franklin's (Larus pipixcan) gulls collected during the same breeding season in colonies in the New York Bight and in northwestern Minnesota, respectively. Concentrations were expected to be higher in young herring gulls collected in an urban, industrialized area, compared to young Franklin's gulls collected in a relatively pristine prairie marsh. Exposure is similar for the fledgling and adult gulls because by the time the blood of young gulls is drawn both adults and young have been eating foods from the surrounding region for two months; leading to the prediction that metal levels should be similar in adults and young. However, young Franklin's gulls had significantly higher levels of arsenic, cadmium, and manganese than adults; adults had significantly higher levels of mercury and selenium. Young herring gulls had significantly higher concentrations of arsenic and selenium, but lower levels of lead than adult herring gulls. Interspecific comparisons indicated that young Franklin's gulls had significantly higher levels of cadmium than young herring gulls, and adult Franklin's gulls had higher levels of selenium and chromium than adult herring gulls, but for all other comparisons herring gulls had higher levels of metals in their blood. Young herring gulls chicks had higher arsenic, manganese, and selenium levels and lower cadmium and lead levels in 1993 than in 1994. Overall, the levels in the two species were usually within an order of magnitude.

Aging

Risk perception, federal spending, and the Savannah River Site: attitudes of hunters and fishermen.

This paper examines the attitudes of 285 hunters and fishermen from South Carolina about hunting and fishing, risk, environmental issues, and future land use of the Savannah River Site, We test the null hypothesis that there is no difference in hunting and fishing rates, attitudes toward the safety of fish and deer obtained from SRS, attitudes toward future land use at SRS, and perceptions of the severity of environmental problems as a function of how far respondents lived from the site. Respondents hunted or fished an average of over 40 days a year, and only half felt that the fish and deer from SRS were safe to eat. Willingness to expend federal funds was correlated with perceptions of the severity of the problem. Preferences for future land use at SRS fell into three categories: high (environmental research park, hunting, fishing, camping), medium (nuclear production, factories, preserve only), and low (nuclear waste storage, residential). There were no differences in hunting and fishing rates, ranking of the severity of environmental problems, and willingness to expend federal funds as a function of distance of residence from SRS, but attitudes toward future land use differed significantly as a function of location of residence. Those living close to SRS were more willing to have the site used for factories, residential, nuclear material production and to store nuclear wastes than those living farther from the site. Our data on recreational rates, attitudes toward future land use, and willingness to expend federal funds to solve environmental problems reiterate the importance of assessing stakeholder attitudes toward decisions regarding future land use at DOE sites.

Adult

Methods for and approaches to evaluating susceptibility of ecological systems to hazardous chemicals.

Differences in genetic susceptibility to hazardous chemicals affect individuals of both human and nonhuman populations. In both cases, differences in response to chemicals or general ill health result as a function of these differences in genetic susceptibility. However, ecological systems are a compilation of hundreds or even thousands of different species, resulting in structural and functional characteristics that are themselves affected by differences in susceptibility. Although individual and population differences in susceptibility to hazardous chemicals underlie effects at the community and the ecosystem level, they do not account for all differences. I propose a two-tiered approach to evaluating susceptibility to ecological systems: a general susceptibility as a function of ecosystem type (based on structure and function of that system) and a differential in susceptibility within broad ecosystem types as a function of biotic and abiotic factors. In terrestrial ecosystems, the two factors that most affect overall susceptibility are species diversity and hydrology; evaluation of the effects of hazardous chemicals involves measuring species diversity and water movement. This same methodological approach can be applied to aquatic ecosystems and to highly altered ecosystems such as agriculture, forestry, fisheries, and urbanization.

Animals