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911.
Dirk Bunke 《Umweltwissenschaften und Schadstoff-Forschung》2003,15(2):106-114
Zusammenfassung Zur Quantifizierung des Gefahrstoffeinsatzes in der Produktion ist im Rahmen der integrierten ?kologischen Bewertung des ?ko-Institutes
(EcoGrade) eine eigene Methodik entwickelt worden. Indikator für den Gefahrstoffeinsatz sind Monoethylenglykol (‘MEG’)-?quivalente.
Sie erm?glichen einen direkten, schadstoffbezogenen Prozess- und Produktvergleich (Bunke 2001). Die Bewertung basiert auf
den R-S?tzen (Gefahrenhinweise) der Inhaltsstoffe. Die Methodik der MEG-?quivalente stellt eine Weiterentwicklung und Anwendung
des Wirkfaktorenmodells der Technischen Regel für Gefahrstoffe (TRGS) 440 dar (AGS 2001). Die zur Bewertung erforderlichen
Daten sind im Unternehmen vorhanden (Sicherheitsdatenbl?tter) bzw. ?ffentlich leicht zug?nglich (Gefahrstoffdatenbanken).
Die Bilanzierung von Gefahrstoffen mit Hilfe der hier vorgestellten Methode erm?glicht es auch, in ?kobilanziellen Untersuchungen
systematisch den Gefahrstoffeinsatz zu berücksichtigen. Die Methodik ist am Beispiel von Wohngeb?uden erprobt worden.
Anmerkung: Als Gefahrstoffe, Schadstoffe, gef?hrliche Inhaltsstoffe bzw. gef?hrliche Stoffe werden in dieser Arbeit solche
Stoffe definiert, die eines der Gef?hrlichkeitsmerkmale nach § 3 Chemikaliengesetz besitzen.
OnlineFirst: 19. 12. 2001 相似文献
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915.
Melissa M. Lunden Kenneth L. Revzan Marc L. Fischer Tracy L. Thatcher David Littlejohn Susanne V. Hering Nancy J. Brown 《Atmospheric environment (Oxford, England : 1994)》2003,37(39-40):5633
Recent studies associate particulate air pollution with adverse health effects; however, the exposure to indoor particles of outdoor origin is not well characterized, particularly for individual chemical species. We conducted a field study in an unoccupied, single-story residence in Clovis, California to provide data and analyses to address issues important for assessing exposure. We used real-time particle monitors both outdoors and indoors to quantify nitrate, sulfate, and carbon particulate matter of particle size 2.5 μm or less in diameter (PM-2.5). The results show that measured indoor ammonium nitrate concentrations were significantly lower than would be expected based solely on penetration and deposition losses. The additional reduction can be attributed to the transformation indoors of ammonium nitrate into ammonia and nitric acid gases, which are subsequently lost by deposition and sorption to indoor surfaces. A mass balance model that accounts for the kinetics of ammonium nitrate evaporation was able to reproduce measured indoor ammonium nitrate and nitric acid concentrations, resulting in a fitted value of the deposition velocity for nitric acid of 0.56 cm s−1. The results indicate that indoor exposure to outdoor ammonium nitrate in Central Valley of California are small, and suggest that exposure assessments based on total particle mass measured outdoors may obscure the actual causal relationships for indoor exposure to particles of outdoor origin. 相似文献
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917.
We designed a microcosm experiment to assess the influence of inoculation with Eisenia foetida earthworms and the establishment of an Avena sativa cover crop on biological (enzyme activities and labile carbon fractions) soil quality indicators in a soil treated with a composted organic residue, and to determine the contribution of these treatments to carbon dioxide emissions from the soil to the atmosphere of the microcosm. The microcosms were incubated for 53 days under 28 °C/18 °C day/night temperatures. The addition of earthworms and the planting of A. sativa increased dehydrogenase activity of compost amended soil by about 44% after 23 days of incubation. The metabolic potential, calculated as the ratio dehydrogenase activity/water soluble C, was higher in the compost amended soil planted with A. sativa. The highest total amount of CO2–C evolved occurred in the soil treated with composted residue and earthworms (about 40% of the total amount of CO2 evolved came from earthworm activity). The planting of A. sativa increased the decomposition rate constant of organic matter in the amended soil but decreased the potentially mineralizable C pool. In conclusion, the establishment of an A. sativa cover crop and the addition of E. foetida to a degraded agricultural soil treated with composted residue were effective treatments for improving the biological and biochemical quality and the metabolic potential of the soil. 相似文献
918.
Hollert H Dürr M Holtey-Weber R Islinger M Brack W Färber H Erdinger L Braunbeck T 《Environmental science and pollution research international》2005,12(6):347-360
Goal, Scope and Background In order to evaluate the estrogenic activity of sediments and XAD water extracts of selected sites of the catchment area
of the River Neckar, a river system in Southern Germany, an integrative assessment approach was used to assess the ecological
hazard potential of endocrine-disrupting compounds in sediment and water.
Methods The approach is based on estrogen receptor-mediated vitellogenin synthesis induced in isolated hepatocytes of rainbow trout
and quantified in a non-radioactive dot blot/RNAse protection-assay in parallel to comprehensive chemical analyses of estrogenic
substances.
Results and Discussion Numerous investigated extracts revealed an estrogen activity comparable to that of the positive control (1 nM 17?-estradiol
corresponding to 270 ng/L in the test medium). Based on a concentration factor of 30 in the extracts and a recovery of XAD
resins of approximately 80 %, 17?-estradiol equivalent concentrations between 20 and 26.7 ng/L could be calculated downstream
of a sewage treatment plant (< 0.1 ng/L for a reference site). A comparison of the bioassay-derived Bio-TEQs (toxicity equivalents)
and the Chem-TEQs revealed a high correlation with a Pearson coefficient of 0.85, indicating that the same ranking of the
samples could be obtained with respect to the endocrine disrupting potential with both chemical and bioanalytical analysis.
However, the TEQ concentrations computed from chemical analyses were significantly lower than the bioassay-derived TEQ concentrations.
In fact, in none of the samples, more than 14 % of the vitellogenin-inducing potency could be attributed to the substances
(steroids, alkylphenols, bisphenol A, diethylstilbestrol) analyzed.
A comparison of the endocrine disrupting potential of sediments extracted by the solvents acetone and methanol revealed lower
biological effects for acetone-extracted samples. Possible reasons may be a masking of endocrine effects in acetone extracts
by cytotoxicity, a low extraction efficiency of the solvent acetone, or anti-estrogen potencies of some extracted sediment
compounds.
Using a mass balance approach, the contribution of the compounds analyzed chemically (Chem-TEQs) to the total endocrine activity
(Bio-TEQs) was calculated. Based on the very low detection limits, particularly of the steroids with their high TEF factors,
results revealed that a calculation of the Chem-TEQs is associated with considerable scale inaccuracy: Whereas only 7-15 %
of the biological effectiveness (Bio-TEQs) could be explained by endocrine substances identified above the detection limits,
the assumption of concentrations slightly below the given detection limits would result in a significant over estimation (137-197
%) of the Bio-TEQs. Even the interassay variation of the dot blot assay with different fish donors for primary hepatocyte
(factor 2 - 2.5) is relatively low, when compared to the large range of the Chem-TEQ concentrations (factor 20) obtained when
applying different modes of calculation.
Conclusions and Outlook Overall, only a minor portion of the endocrine activity detected by bioassays could be linked to compounds identified by
chemical analysis. In vitro assays for assessment of endocrine activities are useful as sensitive integrating methods that
provide quantitative estimates of the total activity of particular receptor-mediated responses. Although discrepancies may
also result from different bioanalytical approaches, it is overall likely that bioanalytical and not chemical analytical approaches
give the correct estimate of endocrine disrupting potencies in environmental samples. As a conclusion, assessment of endocrine
disruption based on chemical analysis alone does not appear sufficient and further research into the spectrum of substances
with potential endocrine activity as well as into additive or even synergistic effects in complex environmental samples is
urgently needed. 相似文献
919.
920.
以磷钨酸为光催化剂,在紫外灯照射下,对模拟染料废水甲基橙溶液进行光催化降解,并研究了催化剂加入量、pH值、甲基橙初始浓度和外加氧化剂H2O2对光催化降解效果的影响.结果表明,磷钨酸光催化剂加入量为300 mg/100 mL,pH=2.5时,甲基橙溶液的降解率明显高于其他pH值的降解率;在较低浓度下,甲基橙溶液的光催化降解反应符合一级动力学方程;外加氧化剂H2O2可提高光催化反应速率. 相似文献