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/análiseRESUMO
Levels of radionuclides in seven species of marine brown algae and Ulva were determined to establish a baseline for the Northern Pacific Ocean/Bering Sea (Aleutian Islands). There were differences in levels among algal species and locations (Amchitka Island vs Kiska Island). No values were above the minimum detectable activity (MDA) level for (137)Cs, (129)I, (60)Co, (152)Eu, (90)Sr, and (99)Tc. There were interspecific differences in some radionuclides: Ulva lactuca (=Ulva fenestrata) had the highest levels of (241)Am, Alaria fistulosa had the highest levels of (239,240)Pu, and Fucus distichus (=Fucus gardneri) had the highest levels of (234)U, (235)U, and (238)U. However, levels of all radionuclides were generally low and near the MDA for all isotopes. Although Amchitka Island had higher levels of (239,240)Pu than Kiska, the differences were very small and not significant biologically. The data indicate that algae can be useful bioindicators of actinides because they accumulate them at very low environmental levels, allowing them to provide early warning of any potential seepage of radionuclides into the marine environment. Further, the data indicate that some species (the intertidal Fucus) are better accumulators than others, and these should be used as bioindicators in future monitoring schemes.
Assuntos
Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Eucariotos/química , Radioisótopos/análise , Alaska , Coleta de Dados , Especificidade da Espécie , Espectrometria gamaRESUMO
This study determined the reliability and validity of a self-administered occupational health history questionnaire. Reliability was evaluated using a test-retest study design based on 123 volunteers (56% participation rate) who were administered the questionnaire approximately 1 month apart. Validity and general acceptability was evaluated in a clinical setting through in-depth clinician interviews of 25 patients. The interviews assessed patients' understanding of and sensitivities to questions and degree of adherence to initial responses after discussing questions with clinicians. All but one question related to repetitive motion exposures showed 84% or higher agreement. Clinician interviews of patients indicated that most questions were well understood, although some patients misinterpreted questions regarding pregnancy history, repetitive motion, and immunization history. Overall, our results suggest that the questionnaire is highly reliable, valid, and acceptable to both clinicians and employees.
Assuntos
Anamnese/métodos , Saúde Ocupacional , Humanos , Medicina do Trabalho , Reprodutibilidade dos Testes , Risco , Inquéritos e QuestionáriosRESUMO
Developing health and safety plans (HASPs) is a common feature of occupational safety and health for many workplaces. Formal HASPs are a requirement for hazardous waste work, requiring the anticipation and identification of hazards and embodying the training, equipping, and evaluation of workers. Aside from OSHA, there are relatively few manuals or examples and virtually no papers that provide practical guidance in what a HASP should cover or how to create and implement one. Moreover, existing guidance refers to spatially circumscribed worksites. This article details development of a HASP to cover field researchers and ship personnel conducting scientific research in a remote area of the world (Amchitka Island in the western Aleutians), hundreds of kilometers from the nearest emergency room. It required characterizing the kinds of work to be performed and anticipating the hazards that could be encountered. It illustrates the meshing of a general HASP with a ship safety plan, a dive safety plan, and specialized topics, including stop-work authority, rock climbing, firearms, vehicle safety, and communication strategy. Remote area operations are a growing challenge facing the profession. An expedition of this sort requires extensive planning and experienced safety personnel and cannot rely on luck to ensure the safe return of participants.
Assuntos
Planejamento em Saúde , Serviços de Saúde do Trabalhador , Gestão da Segurança/métodos , Alaska , Geografia , Implementação de Plano de Saúde , Humanos , Medição de Risco , Estados Unidos , Local de TrabalhoRESUMO
With the ending of the Cold War, the US Department of Energy is responsible for the remediation of radioactive waste and disposal of land no longer needed for nuclear material production or related national security missions. The task of characterizing the hazards and risks from radionuclides is necessary for assuring the protection of health of humans and the environment. This is a particularly daunting task for those sites that had underground testing of nuclear weapons, where the radioactive contamination is currently inaccessible. Herein we report on the development of a Science Plan to characterize the physical and biological marine environment around Amchitka Island in the Aleutian chain of Alaska, where three underground nuclear tests were conducted (1965-1971). Information on the ecology, geology, and current radionuclide levels in biota, water, and sediment is necessary for evaluating possible current contamination and to serve as a baseline for developing a plan to ensure human and ecosystem health in perpetuity. Other information required includes identifying the location of the salt water/fresh water interface where migration to the ocean might occur in the future and determining groundwater recharge balances, as well as assessing other physical/geological features of Amchitka near the test sites. The Science Plan is needed to address the confusing and conflicting information available to the public about radionuclide risks from underground nuclear blasts in the late 1960s and early 1970s, as well as the potential for volcanic or seismic activity to disrupt shot cavities or accelerate migration of radionuclides into the sea. Developing a Science Plan involved agreement among regulators and other stakeholders, assignment of the task to the Consortium for Risk Evaluation with Stakeholder Participation, and development of a consensus Science Plan that dealt with contentious scientific issues. Involvement of the regulators (State of Alaska), resource trustees (U S Fish and Wildlife Service), representatives of the Aleut and Pribilof Island communities, and other stakeholders was essential for plan development and approval, although this created tensions because of the different objectives of each group. The complicated process of developing a Science Plan involved iterations and interactions with multiple agencies and organizations, scientists in several disciplines, regulators, and the participation of Aleut people in their home communities, as well as the general public. The importance of including all parties in all phases of the development of the Science Plan was critical to its acceptance by a broad range of regulators, agencies, resource trustees, Aleutian/Pribilof communities, and other stakeholders.