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81.
The pharmaceutical diclofenac (DCF) is released in considerably high amounts to the aquatic environment. Photo-transformation of DCF was reported as the main degradation pathway in surface waters and was found to produce metabolites with enhanced toxicity to the green algae Scenedesmus vacuolatus. We identified and subsequently confirmed 2-[2-(chlorophenyl)amino]benzaldehyde (CPAB) as a transformation product with enhanced toxicity using effect-directed analysis. The EC50 of CPAB (4.8 mg/L) was a factor of 10 lower than that for DCF (48.1 mg/L), due to the higher hydrophobicity of CPAB (log Kow = 3.62) compared with DCF (log Dow = 2.04) at pH 7.0.  相似文献   
82.
Life cycle assessment-based environmental product declarations (EPDs) require the inclusion of biodiversity impacts across the entire supply chain. The objective of this study is to test the applicability of a Scandinavian biodiversity assessment tool, developed specifically for use with EPD applications, in an African desert environment, linking the industry types power generation and mining. For this purpose, a GIS-based spatial analysis tool—the biotope method—was adapted to a framework approach which allowed the selection of more suitable, site-specific biodiversity indicators. The biotope method provides a step-by-step process of defining system boundaries, mapping biotopes, categorizing biotopes based on site-specific indicators, and evaluating change in biotope status “before” and “after” the impact. The development of site-specific indicators was piloted in this study and determined by the affected ecosystem and the status of knowledge on biodiversity in this geographic area. Thus plants were used as indicators for biodiversity, and red-list status and endemism constituted the prime criteria for conservation value of plants. This in turn represented the key criterion for classifying biotopes. The tested biodiversity assessment tool has potential for application in different environments and operational settings but leaves room for improvement by including secondary impacts in the assessment and using a wider range of taxa for indicators of biodiversity.  相似文献   
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Cardiac defects were studied in five chromosomally abnormal embryos of 10–14 weeks' gestation by free-hand microdissection of hearts measuring 2·5–6 mm in diameter. The type of cardiac malformation alone or in association with other anomalies helped to confirm the chromosome diagnosis established prenatally by chorionic villus sampling or after spontaneous abortion. It was suggestive of a chromosomal disorder in one case in which cytogenetic investigation had failed.  相似文献   
85.
The potential risk of ground-water contamination through the infiltration of contaminants originating from suspended matter and sediments deposited within flood retention areas in the Upper Rhine valley, as well as subsequent problems for drinking water production, were analyzed by means of the bacterial dehydrogenase activity (DHA; sediment contact test) assay with Arthrobacter globiformis and in a prolonged embryo toxicity assay using zebrafish (Danio rerio). Since the direct uptake of contaminants from particle-bound sources has usually been assumed to play only a minor role in bioaccumulation, the availability of organic extracts to biota has generally been regarded as being overestimated. In order to confirm or discard this hypothesis, organic (acetone) extracts of recently suspended, freeze-dried matter, as well as freeze-dried sediments collected from Rhine flood plains (i.e. soil samples) were compared to corresponding native samples in order to screen for the relative availability of particle-bound contaminants. Whereas a significantly higher ecotoxicological burden was observed for some native soil samples, organic extracts of suspended matter proved to be more toxic than corresponding native samples when compared to organic extracts using each test system. With respect to organic extracts, the suspended matter samples were more toxic than soil samples taken from a rarely flooded site. In contrast to the native samples, the rarely flooded soils revealed a higher toxicity than suspended matter. Therefore, organic extracts did not necessarily overestimate the toxicity of soil and suspended matter samples. Moreover, considerable toxicity of particle-bound contaminants to both bacteria and fish embryos, even in native samples, corroborate the hypothesis that particle-bound contaminants may be more readily available than is generally assumed.  相似文献   
86.
Chorionic villus samples from two healthy pregnant females were obtained for first trimester fetal diagnosis. The karyotypes were 46, XX/47, XX, +3 and 46, XX/47, XX, +15, respectively. In both cases fibroblast cultures after termination of pregnancy were shown to have normal karyotypes.  相似文献   
87.
With the increasing public concern over the environment, corporate management is now faced with the problem of first, organizing its efforts to be responsive to the public and legislation, and second, obtaining maximum value for its expenditures. This paper discusses how a firm can approach the problem of deciding when to use environmental consultants and when to perform tasks using an in-house staff organization.  相似文献   
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