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Background  

Export to the deep sea has been found to be a relevant pathway for highly hydrophobic chemicals. The objective of this study is to investigate the influence of this process on the potential for long-range transport (LRT) of such chemicals.  相似文献   
575.
The influence of explosive wastes in soil on the reproduction of the springtailFolsomia candida (Willem 1902) (insects of the Order Collembola) was investigated in a standard test according to ISO-Draft-Guideline 11268-2. In the test, we used soils with 3 different contamination levels from an area used for different military purposes (in Hallschlag, Germany), especially for explosive operations, since the beginning of the century. We found different and heterogenous mixtures of contaminants in the soils (primarily TNT and DNT) which resulted in a high mortality rate among the adult insects and in a dramatic reduction in the reproductive potential of the Collembola. In the mixture of contaminants with the highest contamination levels, the total extinction of exposed Collembola was observed as a result of the death of adult insects.  相似文献   
576.
This report presents the results of a research programme designed to examine the engineering and environmental acceptability of stabilizing municipal solid waste (MSW) combustor ash for artificial reef construction. Municipal solid waste combustor ash was combined with Portland cement to form solid blocks using conventional construction block making technology. the resultant stabilized combustor ash (SCA) blocks were used to construct an artificial habitat in Conscience Bay, Long Island Sound, New York and compared to identical concrete blocks, fabricated using natural aggregates. Over a 4.5 year period divers periodically returned to the site to monitor the interaction of SCA blocks with the marine environment and compare the performance of these blocks with the concrete control blocks. Results show that the SCA blocks retain their strength after prolonged sea water exposure. Contaminants of environmental concern, including metals, dioxins and furans, were retained within the cementitious matrix of the SCA blocks after prolonged sea water submersion. in addition, organisms growing on the surfaces of the SCA blocks did not accumulate contaminants from the blocks.  相似文献   
577.
Urban Air Quality Assessment Model: UAQAM   总被引:1,自引:0,他引:1  
The Urban Air Quality Assessment Model (UAQAM) calculates urban concentrations caused by city emissions themselves, the so-called city background concentration. Three versions of the model for describing the dispersion were studied: Box, Gifford Hanna (GH) and a combined form of these two (Box–GH model). Regional background emissions contributing to the urban background concentration were accounted for by using measurements and calculations from a dispersion model on the continental scale. The results of the three UAQAM versions for a number of European cities were compared to measurements of SO2 and NO X . The Box–GH model shows better results when compared to the Box model and slightly better results in comparison to the GH model. The Box–GH model has been taken as a starting point for the assessment of urban air quality with UAQAM.  相似文献   
578.
Problems exist in the United States' effort to achieve energy self-sufficiency. Increasing coal production to assure energy self-sufficiency is a prime problem for the rest of the century and beyond. The use of diesels in underground coal mines has been suggested as a mining method to aid in this needed, increased production. Many questions exist about the effects on humans in such environments. NIOSH Division of Respiratory Disease Studies has undertaken a research effort to characterize the environments of existing diesel coal mines. The results of one of the studies will be presented. Preliminary assessments of carbon monoxide, nitrogen dioxide, C1-C5 aldehydes and organic acids, aliphatic hydrocarbons, sulfates, total and respirable dust, and polycyclic aromatic hydrocarbons (PAH) are presented. Nitrogen dioxide and total aldehydes are suggested as possible species to quantify diesel exposure.  相似文献   
579.
Haloacetic acids are atmospheric oxidation products of airborne C2-halocarbons which are important solvents and propellants. Levels of trichloroacetate (TCA) in conifer needles from mountain ranges in Germany (Black Forest, Erzgebirge) and from two sites in Finland are compared; TCA is present in conifer needles at concentrations up to 0.7 μmol/kg, MCA up to 0.2 μmol/kg. At the Finnish sites, TCA-concentrations and branch degeneration symptoms of Scots pine are correlated. Monochloroacetate (MCA) has been determined in needle samples from Southern Germany in concentrations exceeding its phytotoxicity threshold towards photoautotrophic organisms. Data on atmospheric chloroacetate levels in Germany are also given; ambient air levels of chloroacetic acids range from about 2 pmol/m3 (TCA) to 390 pmol/m3 (MCA). TCA and dichloroacetic acid (DCA) arise from atmospheric oxidation of airborne C2-chlorocarbons, while the source of MCA is not yet known; several tentative pathways are suggested.  相似文献   
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