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981.
A global assessment of chromium pollution using sperm whales (Physeter macrocephalus) as an indicator species 总被引:1,自引:0,他引:1
John Pierce Wise Sr. Roger Payne Sandra S. Wise Carolyne LaCerte James Wise Christy Gianios Jr. W. Douglas Thompson Christopher Perkins Tongzhang Zheng Cairong Zhu Lucille Benedict Iain Kerr 《Chemosphere》2009,75(11):1461-1467
Chromium (Cr) is a well-known human carcinogen and a potential reproductive toxicant, but its contribution to ocean pollution is poorly understood. The aim of this study was to provide a global baseline for Cr as a marine pollutant using the sperm whale (Physeter macrocephalus) as an indicator species. Biopsies were collected from free-ranging whales around the globe during the voyage of the research vessel The Odyssey. Total Cr levels were measured in 361 sperm whales collected from 16 regions around the globe detectable levels ranged from 0.9 to 122.6 μg Cr g tissue−1 with a global mean of 8.8 ± 0.9 μg g−1. Two whales had undetectable levels. The highest levels were found in sperm whales sampled in the waters near the Islands of Kiribati in the Pacific (mean = 44.3 ± 14.4) and the Seychelles in the Indian Ocean (mean = 19.5 ± 5.4 μg g−1). The lowest mean levels were found in whales near the Canary Islands (mean = 3.7 ± 0.8 μg g−1) and off of the coast of Sri Lanka (mean = 3.3 ± 0.4 μg g−1). The global mean Cr level in whale skin was 28-times higher than mean Cr skin levels in humans without occupational exposure. The whale levels were more similar to levels only observed previously in human lung tissue from workers who died of Cr-induced lung cancer. We conclude that Cr pollution in the marine environment is significant and that further study is urgently needed. 相似文献
982.
Hg concentrations and related risk assessment in coral reef crustaceans, molluscs and fish from New Caledonia 总被引:1,自引:0,他引:1
Chouvelon T Warnau M Churlaud C Bustamante P 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):331-340
There is a dramatic lack of data on Hg levels in marine organisms from tropical areas, and in particular from New Caledonia. For the first time, this study reports the total Hg concentrations in the tissues of several marine taxa from the New Caledonian lagoon. Seafood from both wild and farmed populations was considered. Hg concentrations varied over three orders of magnitudes according to factors including species, age (size/weight), trophic level, lifestyle and geographical origin. Taking into account the edible tissues, estimations of the amount of flesh that should be consumed by a 60-kg person to reach the Hg Provisional Tolerable Weekly Intake (PTWI) reveal acceptable risk for Human health in general. However, a risk was clearly identified in one site of the lagoon (i.e. Grande Rade) where high Hg concentrations were measured. These concentrations were higher than values reported in the current literature. 相似文献
983.
984.
自然资源利用权从产生的途径上看应属于特许物权,从内容和功能上看应属于准用益物权,两种物权属性并不相互排斥。自然资源利用权的双重物权属性符合环境保护的价值取向和价值选择。 相似文献
985.
986.
王紫零 《中国环境管理干部学院学报》2009,19(4):48-51
我国现在正处于环境事故高发期,而环境污染损害赔偿是企业,甚至是国家必须面对的现实问题。然而单凭企业承担责任是力所不能及的,最终不得不由国家买单,给国家带来沉重的负担。这种情况迫切需要建立环境污染损害责任保险机制,即绿色保险,把赔偿引向社会化。保险本身就是一种救灾形式,因为它能分散风险,减少损失。针对我国的具体情况,建立适宜的环境污染责任保险模式才能平衡发展与环境保护的关系、在全社会牢固树立生态文明理念。 相似文献
987.
耿世刚 《中国环境管理干部学院学报》2009,19(4):1-4
在对当前国际国内环境保护大背景分析的基础上,阐述了构建现代产业体系与环境保护的关系,以及生态文明、科学发展观、可持续发展战略、循环经济、清洁生产等与环境保护相关的关键词,提出构建现代产业体系,必须与环境保护体系建设同步进行,将最新的环保理念和思想纳入到现代产业体系的构建之中,并从环保政策上给与支持。 相似文献
988.
Michael W. Suplee Vicki Watson Mark Teply Heather McKee 《Journal of the American Water Resources Association》2009,45(1):123-140
Abstract: A public opinion survey was carried out in Montana to ascertain if the public identifies a level of benthic (bottom‐attached) river and stream algae that is undesirable for recreation. The survey had two parts; an On‐River survey and a By‐Mail survey. The On‐River survey was conducted via 44 trips randomly scheduled throughout the state during which recreators were interviewed in‐person at the stream. Selection of stream segments and survey dates/times was based on known, statewide recreational use patterns. By‐Mail survey forms were sent to 2,000 individuals randomly selected from Montana’s Centralized Voter File (CVF) available from the Montana Secretary of State. The CVF was current through 2004 and represented over 85% of the state’s eligible voting population. In both surveys, eight randomly ordered photographs depicting varying levels of stream benthic algae were presented, and participants were asked if the algae level shown was desirable or undesirable for recreation. Survey form design, selection of photographs, and pretesting followed acceptable protocols that limited unintentional bias through survey execution. There were 433 returned forms (389 complete) for the By‐Mail survey, while the On‐River survey documented 563 interviews. In both surveys, as benthic algal chlorophyll a (Chl a) levels increased, desirability for recreation decreased. (Other measures of benthic algae biomass are presented as well.) For the public majority, mean benthic Chl a levels ≥200 mg/m2 were determined to be undesirable for recreation, whereas mean levels ≤150 mg Chl a/m2 were found to be desirable. Error rates were within the survey’s statistical design criteria (≤5%). The largest potential error source was nonresponse in the By‐Mail survey; however, the population represented by nonrespondents would have to exhibit profoundly different perceptions of river and stream algae to meaningfully alter the results. Results support earlier work in the literature suggesting 150 mg Chl a/m2 represents a benthic algae nuisance threshold. 相似文献
989.
E. Howard Coker Rollin H. Hotchkiss Dennis A. Johnson 《Journal of the American Water Resources Association》2009,45(4):815-827
Abstract: A present and future challenge for water resources engineers is to extend the useful life of our dams and reservoirs. Ongoing reservoir sedimentation in impoundments must be addressed; sedimentation in many reservoirs already limits project benefits and effective project life. Sustainability requires that incoming sediment be moved downstream past the impounding dam. We use Lewis and Clark Lake, the most downstream of the six Missouri River main stem reservoirs, to demonstrate how a reservoir in advanced stages of its project life could be converted to a sustainable system with local benefits exceeding costs by a factor of 1.5. Full consideration of benefits would further enhance project justification. The proposed strategy involves four phases that will take about 50 years to complete. Cost estimates for this potential project range from the quantitative to the plausible, but it is clear that the results justify a full engineering, environmental, and economic study of this model project. If implemented, the project will create scientific knowledge and develop technologies useful for achieving sustainability at many other reservoirs in the Mississippi River basin and beyond. 相似文献
990.