巴西亚马孙河流域雅诺马马人体内的有机汞含量

位于巴西北部的Catrimani河流域是雅诺马马人的居住地,且自1980年以来,一直是采金场所.金矿开采活动释放入环境中的无机汞会被转化为有机汞,且在水域生态系统会发生生物放大作用.摄食被汞污染鱼的人群,如雅诺马马人有可能会受到危害.我们分别于1994年和1995年对居住在采矿河流附近和非采矿河流附近的雅诺马马村民进行了调查,并且对被其捕捞的水虎鱼体内的汞含量进行了分析.我们分别于1994和1995年对5个村庄的90名雅诺马马印地安人和3个村庄的62名雅诺马马印地安人进行了调查研究.于1994年所调查的5个村庄中,有4个位于Catrimani河沿岸,大约在距过去金矿开采活动场所下游140～160km处.另一个村庄位于没有开采活动的ajaraní河沿岸.于1995年所调查的3个村庄中,有两个位于Catrimani河沿岸的村庄再一次被调查,另一个位于没有采矿活动的Pacu河.在被调查的所有村民中,其血液中有机汞含量的变化范围为0～62.6μg/L(每个村庄的平均值在21.2～43.1μg/L之间).采自有采矿活动的Catrimani河的水虎鱼汞含量的变化范围为235～1084ppb.在所测的13个水虎鱼样品中,有9个体长在30cm或更长的水虎鱼样品总汞含量超过了世界卫生组织和巴西卫生部规定的鱼中汞消费限值(500ppb).不幸的是,在没有开采活动的Ajaraní和Pacu河附近的居民和鱼体内都呈现出了较高的汞水平,这表明间接的汞源也会对亚马孙河流域造成环境污染.     

Prenatal diagnosis of tetrasomy 21

Amniocentesis and prenatal diagnosis were done for late maternal age and an abnormality consistent with Tetrasomy 21 (47,XX,+t(21;21)) was found in every cell examined of the initial amniotic fluid. Clinical examination revealed a fetus with many of the signs of Down Syndrome and pathological examination revealed gross abnormalities of the internal structures. Follow-up tissues showed mosaic Tetrasomy 21.     

Sea-level rise: Destruction of threatened and endangered species habitat in South Carolina

Concern for the environment has increased over the past century, and the US Congress has responded to this concern by passing legislation designed to protect the nation’s ecological biodiversity. This legislation, culminating with the Endangered Species Act of 1973, has been instrumental in defining methods for identifying and protecting endangered or threatened species and their habitats. Current legislation, however, assumes that the range of a protected species will stay constant over time. This assumption may no longer be valid, as the unprecedented increase in the number and concentration of greenhouse gases in the atmosphere has the potential to cause a global warming of 1.0–4.5°C and a sea-level rise (SLR) of 31–150 cm by the year 2100. Changes in climate of this magnitude are capable of causing shifts in the population structure and range of most animal species. This article examines the effects that SLR may have on the habitats of endangered and threatened species at three scales. At the regional scale 52 endangered or threatened plant and animal species were found to reside within 3 m of mean sea level in the coastal stages of the US Southeast. At the state level, the habitats of nine endangered or threatened animals that may be at risk from future SLR were identified. At the local level, a microscale analysis was conducted in the Cape Romain National Wildlife Refuge, South Carolina, USA, on the adverse effects that SLR may have on the habitats of the American alligator, brown pelican, loggerhead sea turtle, and wood stork. Prepared by the Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, Tennessee 37831, USA; managed by Martin Marietta Energy Systems. Inc. for the US Department of Energy under contract DE-AC05-84OR21400.     

Current use of bioremediation for TCE cleanup: Results of a survey

In 1995 the University of Tennessee's Waste Management Research and Education Institute and Canon Inc. began an analysis of the extent to which remediation firms and research centers have implemented bioremediation strategies, particularly for the cleanup of trichloroethylene (TCE) in soil and groundwater. The research involved the mailing of surveys to a select, representative group of environmental professionals involved in TCE cleanup activities. The survey was divided into two parts. Part I gathered cost information for TCE cleanup, using both bioremediation and “conventional” cleanup technologies. Part II asked the survey recipients to relate their opinions on the use of nonindigenous microorganisms for bioremediation, especially their assessment of the effectiveness, reliability, safety, and predictability of this approach. The results of this survey are discussed in this article.     

Effects of 17α-trenbolone and melengestrol acetate on Xenopus laevis growth, development, and survival

The synthetic growth-promoting hormones trenbolone and melengestrol acetate have been detected in the environment near beef cattle feedlots and are reportedly transported via wind-borne particulate matter. Therefore, movement of synthetic hormones from beef cattle feedlots to water bodies via particulate matter is possible. Our objective was to evaluate potential effects of 17α-trenbolone (17α-TB), melengestrol acetate (MGA), and combinations of both on growth, development, and survival of Xenopus laevis larvae. On post-hatch day 2 (stage 33/34), X. laevis larvae were exposed to three nominal concentrations of 17α-TB (10, 100, and 500 ng/L), MGA (1, 10, and 100 ng/L), a combination of both (1/10, 10/100, and 100/500 ng/L MGA/17α-TB), frog embryo teratogenesis assay-Xenopus medium, or a solvent control. Significant increases in all X. laevis growth metrics were observed among larvae in the 1 ng/L MGA?+?10 ng/L 17α-TB and 10 ng/L MGA?+?100 ng/L 17α-TB treatments. Stage of development was increased among larvae in the 1 ng/L MGA?+?10 ng/L 17α-TB treatment group and significantly decreased among those in the 500 ng/L 17α-TB treatment. Total body mass and snout–vent length of X. laevis larvae were significantly reduced in the 100 ng/L MGA and 100 ng/L MGA?+?500 ng/L 17α-TB treatment groups. Larvae exposed to 500 ng/L 17α-TB had decreased total body mass, snout–vent length, and total length. In general, growth measurements decreased with increasing concentration of MGA, 17α-TB, or a combination of both. Survival among all treatments was not significantly different from controls. Amphibians exposed to MGA and 17α-TB in the environment may experience alterations in growth and development.     

Impact of growth conditions on transport behavior of E. coli

The aim of this investigation is to determine the effect that growth solution has on the cell surface properties and transport behavior of eleven Escherichia coli isolates through saturated porous media. The two growth solutions used were a standard laboratory growth medium (LB) and a dairy manure extract solution. In general, cells grown in manure extract were more hydrophobic, had a more negative zeta potential, had lower amounts of surface macromolecules, and had lower attachment efficiencies than isolates grown in LB. An inverse relationship between the natural log of zeta potential and the attachment efficiency of the isolates for the cells grown in LB media was the only statistically significant correlation observed between transport behavior and cell characteristics of the isolates. This study shows the need to consider growth conditions when studying bacteria to better mimic the environmental stresses that bacteria undergo in the natural environment. This approach could lead to a better understanding of the behavior of manure-derived bacteria in aquatic and terrestrial environments.     

Integrating fast feedback and GIS to plan for important agricultural land designations in Kauai County,Hawaii

With increased affluence worldwide, planning for and preserving land for agriculture and conservation have become important goals in many communities. In Hawaii, the identification and designation of Important Agricultural Land (IAL) was first proposed at the 1978 Hawaii Constitutional Convention and approved by voters the same year. The state is required to conserve and protect agricultural lands, promote diversified agriculture, increase agricultural self-sufficiency, and assure the availability of agriculturally suitable lands. Act 183 in 2005 extended these efforts by defining IAL. The law established eight criteria to evaluate IAL and created county-led and landowner-initiated processes for designating IAL. It also specified policies for promoting agricultural production and identified landowner incentives for the designation of IAL. A central challenge facing policymakers is how to operationalize and implement these land use policies. This paper describes methods used to operationalize Act 183. We use fast feedback (i-Clicker technology) devices for capturing stakeholder preferences and geographic information systems and community mapping to visualize policy impacts and integrate community feedback. The methods developed in this paper have broad applications to jurisdictions around the world looking for data-driven approaches to planning and designating land uses according to legislative mandates or administrative requirements.