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Hair-biomonitoring of organic pollutants   总被引:1,自引:0,他引:1  
Schramm KW 《Chemosphere》2008,72(8):1103-1111
This report reviews past research on hair analysis development for organic contaminants from the point of view of analytical procedures, successful applications and their limitations. For the past 20 years, hair analysis for organic pollutants has received more and more attention, since it is non-invasive, easily available and ethically not prioritized. New methods such as SFE, SPME and INAA have been developed to make the analysis more accurate and reliable. Furthermore, the correlation of contamination levels between hair samples and ambient air or internal tissues has been found by hair analysis and short-term and long-term exposure assessment in combination. However, there are still some limitations of hair analysis to be a validated risk assessment tool for many compounds. Some limitations had been of the past, some have not been fully investigated and need still further study. In this way, hair analysis can be the key to successfully biomonitor organic contaminations.  相似文献   
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Determination photostability of selected agrochemicals in water and soil.   总被引:5,自引:0,他引:5  
The photolysis of selected pesticides in aqueous solutions has been investigated. The photolysis produced different intermediate substances, which were also found to be soil and microbial degradation products. The phototransformation in the presence of TiO2 and humic substances leads to a disappearance of these compounds. The reaction rate is dependent on the semiconductor oxide and concentration. Photoproducts were isolated and characterized by different spectroscopic methods. Results from this study indicate that degradation products of isoproturon are more toxic on Daphnia magna than on the parent compound.  相似文献   
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We investigate the phylogeography of California (Zalophus californianus) and Galápagos (Z. wollebaeki) sea lions and describe within-population structure for the California sea lion based on mitochondrial DNA. Fifty control-region haplotypes were found, 41 from Z. californianus and 9 from Z. wollebaeki, with three fixed differences between the two species. Ranked population boundaries along the range of Z. californianus were defined based on the Monmonier Maximum Difference Algorithm, resulting in five genetically distinct populations, two in the Pacific Ocean and three inside the Gulf of California. A Minimum Spanning Network showed a strong phylogeographic signal with two well-defined clusters, Z. californianus and Z. wollebaeki, separated by six base-pair differences, supporting the existence of two genetically distinct species with an estimated divergence time of ~0.8 Ma. Results are discussed in the context of the historical geologic and paleoceanographic events of the last 1 Ma in the eastern Pacific.  相似文献   
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Several household consumer products were analyzed for their content of perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and fluorotelomer alcohols (FTOH) by nanoflow ultra performance liquid chromatography – mass spectrometry and gas chromatography – mass spectrometry. Among the investigated products, which are applied as sprays, were impregnating agents, cleaning agents, lubricants, and conditioners. In 14 of the 26 products analyzed, at least one polyfluorinated compound (PFC) was detected in 14 samples. 8?:?2 FTOH was the dominating PFC with concentrations up to 149?µg?mL?1. The maximum concentration of PFOA was 14.5?µg?mL?1, whereas PFOS was not detected in any sample. Investigated PFCs were mostly found in impregnating agents and lubricants, but were not detected in cleaning agents and conditioners. In FTOH-containing impregnating agents, similar ratios between 6?:?2 FTOH, 8?:?2 FTOH, and 10?:?2 FTOH were found. FTOH proportions in PFC-containing lubricants were similar as well. Total human exposure to PFC from consumer product aerosols for three different scenarios was estimated to be between 42.8 and 464?ng?kg?1?per day.  相似文献   
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The effect of light intensity on rate of photosynthesis was measured at irregular intervals over a 12-month period for 22 benthic marine algae in the western Baltic Sea. In most species photosynthesis (mg O2·g dry weight-1·h-1) was highest in spring and summer, corresponding to the seasonal growth pattern of the algae. In winter all the species showed adaptation of the light compensation point. Highest productivity was shown by algae which are: short-lived annual species rather than perennials, eulittoral rather than sublittoral, and which possess sheet-like or filamentous thalli rather than coarsely branched forms. These factors are clearly inter-related.This research was carried out while one of us (R.J.K.) was an Alexander von Humboldt fellow at the University of Kiel, and is part of the programme Sonderforschungsbereich 95, Wechselwirkung Meer-Meeresboden, Universität Kiel.  相似文献   
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