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31.
Divergent scientific and regulatory agency perspectives about contaminants in fish have lead to contradictory advice and confusing public messages about its consumption. The evidence for the protective effect of eating fish on cardiovascular outcomes is considered to be convincing. It has long been attributed to n-3 unsaturated long-chain fatty acids. Persistent organic pollutants (POPs) are compounds that are lipid soluble and accumulate in the aquatic food chain. Despite a considerable decrease in their levels in fish during the last two decades, there is still significant concern about potential negative health effects and an ongoing debate exists about what type of fish consumption advisories are most suitable. In this review our aim is twofold, namely to explore: (1) the underlying causes for the conflicting recommendations by discussing the strengths and limitations of risk assessment and epidemiological evidence; and (2), the role of risk management in formulating public dietary advisories. It is our view that the latter advice is most appropriately formulated in the context of risk management, of which both epidemiologic evidence and risk assessment are essential components.  相似文献   
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ABSTRACT

A maximum information entropy method of calculating probabilistic estimates of volatile organic compound (VOC) emissions by the wood furniture and fixture coating industry is presented. The maximum entropy approach is used to produce minimally biased probability distributions for number of firms, coating use, and coating emission factors from existing summary statistics. These distributions are combined to estimate VOC emissions. The maximum entropy emissions estimate provides information to support probabilistic modeling of regional air quality, probabilistic assessment of emission reduction strategies, and risk assessments. Accurate estimation of emission distributions produces more informed regulatory decisionmaking, risk comparisons, and regulatory and scientific priority setting.  相似文献   
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In organic philosophy, the concept of “naturalness” is of major importance. According to the organic interpretation of animal welfare, natural living is considered a precondition for accomplishing welfare and the principal aims of organic production include the provision of natural living conditions for animals. However, respective regulations are lacking in organic legislation. In practice, the life of a calf in organic rearing systems can deviate from being natural, since common practices in dairy farms include early weaning, dehorning, or cow-calf separation soon after birth. This case study explores how calf welfare is approached in six different organic dairy farms and how far the concept of naturalness is implemented. The farms included in this study were located in Norway and Sweden. A semi-structured questionnaire was used for data collection. The interviewed farmers approach the concept of welfare in various ways and state that “naturalness” is an aspect of animal welfare. However, in practice in the calf rearing systems under study, only a few “naturalness” aspects were implemented. Reasons for the observed discrepancy might lie in differing understandings of “naturalness,” in economic restrictions, and in other trade-offs resulting from production system inherent characteristics and in limited regulation concerning provision of natural living aspects.  相似文献   
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P.O Darnerud     Bergman  B.O Lund  I Brandt 《Chemosphere》1989,18(9-10):1821-1827
Three 14C-labelled polychloroalkanes (C12 and C16), representing low (23% Cl by weight), medium (51%), and highly (68%) chlorinated paraffin (CP) mixtures, were presented to rainbow trout via the water. The uptake in fat-rich tissues was positively correlated to the degree of chlorination of the preparations. Notably, all preparations gave rise to a high and selective uptake of radioactivity in the olfactory organ and gills. This selective radiolabelling may reflect a general ability of these organs to enrich xenobiotics from the surrounding water. The olfactory organ may be a hitherto unforseen target for toxic environmental pollutants in fish.  相似文献   
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Recently the European Council agreed on a CO2 reduction target of 10% by the year 2010. In accordance with this, Denmark decided to reduce its CO2 emissions by 25% over the same time period. One important element of both the European and Danish agreements is energy saving in industries and in private households. Typically industries and private households are also expected to participate in other kinds of environmental improvements, e.g. waste treatment. Such improvements in environmental performances are normally accounted for. In industry, for example, green accounting or environmental auditing are techniques used to measure progress in environmental performance. But when it comes to the environmental performance of people or households very few book-keeping principles have been developed. This paper describes a Danish share-housing project's efforts to formulate an environmental policy and outline an environmental accounting system which can keep track of a household environmental record. It describes the environmental accounting methods, the results and experiences from its first five years.  相似文献   
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Antarctic fishes contain large quantities of lipid in adipose tissue, blood and oxidative muscle. In this study, the fatty acyl compositions of free fatty acids (FFA) and triacylglycerol (TAG) in serum, adipose tissue and oxidative muscle were determined in two species of Antarctic fishes, Trematomus newnesi Boulenger, 1902, and Notothenia gibberifrons Lönnberg, 1905, collected off the Antarctic Peninsula in February and March 1987. Total lipid contents of serum and oxidative muscle in each species also were measured. T. newnesi, a mesopelagic species, has significantly more lipid in the serum than N. gibberifrons, a demersal species (17.6±2.4 and 10.4±1.0 mg lipid g-1 serum, respectively). The oxidative muscle of T. newnesi also contains more lipid than does that of N. gibberifrons (12.5 and 9.3% by dry weight, respectively). Fatty acids comprising greater than 5% of one or more of the lipid pools assayed in both species include 14:0, 16:0, 16:1, 16:2, 18:0, 18:1, 20:5 and 22:6. The percentages of 16:1 were lower (p<0.05) in oxidative muscle FFA than in all other assayed lipid pools in both species, suggesting a catabolic preference for some monoenes in oxidative muscle of these fishes. The percentage of 14:0 was two-to three-fold higher in adipose tissue TAG than in all other lipid pools in both species. Differences in fatty acid compositions between lipid pools indicate than proteins involved in the mobilization, transport or catabolism of fatty acids exhibit differential recognition of fatty acids in T. newnesi and N. gibberifrons.  相似文献   
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A high proportion of school teachers report that they are disturbed by noise during teaching. The aim of the study was therefore to identify determinants of self-reported noise exposure and disturbance attributed to noise among secondary school teachers (n = 419) in 10 schools in Copenhagen, Denmark. The schools were selected to show contrasts in classroom reverberation times (RT), and were classified as “Short RT” (3 schools, mean RT 0.41–0.45 s), “Medium RT” (3 schools, mean RT 0.51–0.55 s) and “Long RT” (4 schools, mean RT 0.62–0.73 s). Significant determinants of self-reported noise exposure were a high number of children in the class, young age of the children, and low teacher seniority. “Long RT” classification was of borderline significance. Significant determinants of disturbance attributed to noise from children in the class were teacher seniority and “Long RT” acoustic classification of the school. The associations between work characteristics and noise disturbance measures were attenuated by low self-rated work capacity, suggesting that the consequences of noise and poor acoustics may not be limited to disturbance attributed to noise, but may have a wide negative impact on the perceived working environment.  相似文献   
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