Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
País como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Risk Anal ; 28(5): 1261-72, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18657067

RESUMO

It is becoming increasingly clear that scientists, managers, lawyers, public policymakers, and the public must decide how to value what is provided by, and is a consequence of, natural resources. While "Western" scientists have clear definitions for the goods and services that ecosystems provide, we contend that these categories do not encompass the full totality of the values provided by natural resources. Partly the confusion results from a limited view of natural resources derived from the need to monetize the value of ecosystems and their component parts. Partly it derives from the "Western" way of separating natural resources from cultural resources or values, and partly it derives from the false dichotomy of assuming that ecosystems are natural, and anything constructed by man is not natural. In this article, we explore the previous assumptions, and suggest that because cultural resources often derive from, and indeed require, intact and unspoiled natural ecosystems or settings, that these values are rightly part of natural resources. The distinction is not trivial because of the current emphasis on cleaning up chemically and radiologically contaminated sites, on restoration of damaged ecosystems, on natural resource damage assessments, and on long-term stewardship goals. All of these processes depend upon defining natural resources appropriately. Several laws, regulations, and protocols depend upon natural resource trustees to protect natural resources on trust lands, which could lead to the circular definition that natural resources are those resources that the trustees feel they are responsible for. Where subsistence or tribal peoples are involved, the definition of natural resources should be broadened to include those ecocultural attributes that are dependent upon, and have incorporated, natural resources. For example, a traditional hunting and fishing ground is less valued by subsistence peoples if it is despoiled by contamination or physical ecosystem degradation; an Indian sacred ground is tarnished if the surrounding natural environment is degraded; a traditional homeland is less valued if the land itself is contaminated. Our argument is that intact natural resources are essential elements of many cultural resources, and this aspect requires and demands adequate consideration (and may therefore require compensation).


Assuntos
Conservação dos Recursos Naturais , Cultura , Ecossistema , Saúde Ambiental , Monitoramento Ambiental/métodos , Grupos Populacionais , Alaska , Recuperação e Remediação Ambiental , Humanos , Inuíte
2.
Sci Total Environ ; 384(1-3): 93-105, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17590413

RESUMO

Considerable attention has been devoted to contaminants (mainly PCBs and mercury) in subsistence foods (particularly fish) from various parts of the world. However, relatively little attention has been devoted to examining mercury levels in a full range of subsistence foods from a particular region. While managers and scientists compute risk based on site-specific data on contaminant levels and consumption rates, a first step in making risk decisions by subsistence peoples is knowledge about the relative levels of mercury in the foods they eat. This study examined levels of mercury in subsistence foods (edible components) from several islands in the western Aleutians of Alaska, including algae (4 species), invertebrates (9 species), fish (15 species) and birds (5 species). Samples were gathered by both subsistence hunters/fishers and by scientists using the same equipment. Another objective was to determine if there were differences in mercury levels in subsistence foods gathered from different Aleutian islands. We tested the null hypotheses that there were no interspecific and interisland differences in mercury levels. Because of variation in distribution and the nature of subsistence hunting and fishing, not all organisms were collected from each of the islands. There were significant and important differences in mercury levels among species, but the locational differences were rather small. There was an order of magnitude difference between algae/some invertebrates and fish/birds. Even within fish, there were significant differences. The highest mean mercury levels were in flathead sole (Hippoglossoides elassodon, 0.277 ppm), yellow irish lord (Hemilepidotus jardani, 0.281 ppm), great sculpin (Myoxocephalus polyacanthocephalus, 0.366 ppm), glaucous-winged gull (Larus glaucescens, 0.329 ppm) and its eggs (0.364 ppm), and pigeon guillemot (Cepphus columba, 0.494 ppm). Mercury levels increased with increasing weight of the organisms for limpets (Tectura scutum), and for 11 of the 15 fish species examined. Nine of the 15 fish species had some samples over the 0.3 ppm level, and 7 of 15 fish had some samples over 0.5 ppm. For birds, 95% of the pigeon guillemot muscle samples were above the 0.3 ppm, and 43% were above 0.5 ppm. While health professionals may argue about the risk and benefits of eating fish, and of eating alternative protein sources, the public should be provided with enough information for them to make informed decisions. This is particularly true for subsistence people who consume large quantities of self-caught foods, particularly for sensitive sub-populations, such as pregnant women. We argue that rather than giving people blanket statements about the health benefits or risks from eating fish, information on mean and maximum mercury levels should also be provided on a wide range of subsistence foods, allowing informed decisions, especially by those most at risk.


Assuntos
Monitoramento Ambiental , Contaminação de Alimentos , Mercúrio/análise , Alaska , Animais , Cadeia Alimentar , Geografia , Humanos , Medição de Risco
3.
Health Phys ; 92(3): 265-79, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17293699

RESUMO

Amchitka Island (51degrees N lat, 179 degrees E long) was the site of three underground nuclear tests from 1965-1971. There have been no substantive studies of radionuclides in marine fishes and birds in the area since the mid-1970's. In this study, levels of 60Co, 52Eu, 90Sr, 99Tc, 129I, 137Cs, and the actinides (241Am, 238Pu, 239,240Pu, 234U, 235U, 236U, and 238U) were studied in ten marine fish species (including Pacific Cod Gadus macrocephalus and Pacific Halibut Hippoglossus stenolepis) and five marine bird species (including Glaucous-winged Gulls Larus glaucescens, Tufted Puffins Fratercula cirrhata, and Common Eider Ducks Somateria mollissima) from Amchitka. The same species were collected at a reference site, Kiska Island (52 degrees N lat; 177 degrees E long), about 130 km west of Amchitka. Each sample was a composite of edible muscle from five or more individual fish or birds of similar size (+/-15%) from the same sampling station. The null hypotheses of no differences among species or between Amchitka and Kiska were tested. Most analytic results were below the minimum detectable activity (MDA), even when 1,000 g sizes and 72 h counting times were used. The only radionuclides detected above the MDA were 137Cs, 241Am, 239,240Pu, 234U, 235U, and 238U. There were significant differences in 137Cs as a function of species, but not location, for top predatory fishes. Of the fishes, eight of ten species had 137Cs values above the MDA for some samples; only one bird, Glaucous-winged Gull, had 137Cs values above the MDA. The highest concentrations of 137Cs were in Dolly Varden [Salvelinus malma, 0.780 (Bq kg(-1) wet weight)] and Pacific Cod (0.602 Bq kg(-1)). In aggregate for any actinides, 73 of 234 (31%) composites for fish were above the MDA, compared to only 3 of 98 (3%) for birds. 234U and 238U, radionuclides that are primarily natural in origin, were routinely detected in these biological samples, but there were no significant differences in mean concentrations between Amchitka and Kiska. The concentrations of all radionuclides examined at Amchitka are similar to those of other uncontaminated Northern Hemisphere sites, and are lower than those reported for fishes and birds from the Irish Sea in the vicinity of the Sellafield nuclear reprocessing facility, an area with known contamination.


Assuntos
Elementos da Série Actinoide/análise , Aves , Monitoramento Ambiental/métodos , Peixes , Monitoramento de Radiação , Radioisótopos/análise , Alaska , Animais , Radioisótopos de Césio/análise , Valores de Referência , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise
4.
Environ Res ; 101(1): 34-41, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16174519

RESUMO

Recreational and subsistence fishing plays a major role in the lives of many people, although most Americans obtain their fish from supermarkets or other commercial sources. Fish consumption has generally increased in recent years, largely because of the nutritional benefits. Recent concerns about contaminants in fish have prompted federal and state agencies to analyze fish (especially freshwater fish targeted by recreational anglers) for contaminants, such as mercury and polychlorinated biphenyls (PCBs), and to issue fish consumption advisories to help reduce the public health risks, where warranted. Scientists engaged in environmental sampling collect fish by a variety of means, and analyze the contaminants in those fish. Risk assessors use these levels as the basis for their advisories. Two assumptions of this methodology are that scientists collect the same size (and types) of fish that fishermen catch, and that, for some contaminants (such as methylmercury and PCBs), levels increase with the size and age of the fish. While many studies demonstrate a positive relationship between size and mercury levels in a wide range of different species of fish, the assumption that scientists collect the same size fish as fishermen has not been examined. The assumption that scientists collect the same size fish as those caught (and eaten) by recreationalists or subsistence fishermen is extremely important because contaminant levels are different in different size fish. In this article, we test the null hypothesis that there are no differences in the sizes of fish collected by Aleut fishermen, scientists (including divers), and commercial trawlers in the Bering Sea from Adak to Kiska. Aleut fishermen caught fish using rod-and-reel (fishing rods, hook, and fresh bait) from boats, as they would in their Aleutian villages. The scientists collected fish using rod-and-reel, as well as by scuba divers using spears up to 90 ft depths. A fisheries biologist collected fish from a research/commercial trawler operated under charter to the National Oceanographic and Atmospheric Administration (NOAA). The fish selected for sampling, including those caught commercially in the Bering Sea, represented different trophic levels, and are species regularly caught by Aleuts while fishing near their villages. Not all fish were caught by all three groups. There were no significant differences in length and weight for five species of fish caught by Aleuts, scientists, and fisheries trawls, and for an additional 3 species caught only by the Aleut and scientist teams. There were small, but significant, differences in the sizes of rock greenling (Hexagrammos lagocephalus) and red Irish lord (Hemilepidotus hemilepidotus) caught by the scientist and Aleut fishermen. No scientists caught rock greenling using poles; those speared by the divers were significantly smaller than those caught by the Aleuts. Further, there were no differences in the percent of males in the samples as a function of fishing method or type of fishermen, except for rockfish and red Irish lord. These data suggest that if scientists collect fish in the same manner as subsistence fishermen (in this case, using fishing rods from boats), they can collect the same-sized fish. The implications for exposure and risk assessment are that scientists should either engage subsistence and recreational fishermen to collect fish for analysis, or mimic their fishing methods to ensure that the fish collected are similar in size and weight to those being caught and consumed by these groups. Further, total length, standard length, and weight were highly correlated for all species of fish, suggesting that risk assessors could rely on recreational and commercial fishermen to measure total lengths for the purpose of correlating mercury levels with known size/mercury level relationships. Our data generally demonstrate that the scientists and trawlers can collect the same size fish as those caught by Aleuts, making contaminant analysis, and subsequent contaminant analysis, representative of the risks to fish consumers.


Assuntos
Exposição Ambiental , Peixes/anatomia & histologia , Contaminação de Alimentos , Alaska , Animais , Tamanho Corporal , Feminino , Humanos , Inuíte , Masculino , Pessoal de Laboratório Médico , Recreação , Medição de Risco , Alimentos Marinhos , Poluentes Químicos da Água
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa