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421.
活性污泥中细菌对邻苯二甲酸酯的降解及其途径   总被引:1,自引:0,他引:1  
用从活性污泥中分离到的菌种对邻苯二甲酸(PA)和邻苯二甲酸二甲酯(DMPE)进行好氧条件降解研究,检测了分离到的5种细菌降解邻苯二甲酸和邻苯二甲酸二甲酯的能力.结果表明,Comamonas acidovorans Fy-1在48h内将浓度高达2600mg/L的邻苯二甲酸完全矿化;两个细菌的组合(组合Ⅰ包括Pseudomonas fluorescens,P aureofacien 和Sphingomonas paucimobilis;组合Ⅱ包括S. paucimobilis和Xanthomonas maltophilia)能够在48~120h内将邻苯二甲酸二甲酯完全降解,产生的中间产物有邻苯二甲酸一甲酯和邻苯二甲酸.结果表明,邻苯二甲酸二甲酯的微生物降解需要有两种以上细菌才能完成.图4表1参14  相似文献   
422.
生物农药对松材线虫(Burasphelenchus xylophilus)室内毒力的测定表明,6102和褐僵菌素Aschersonia sp.具有较强的控制线虫能力。  相似文献   
423.
农药残留分析样品前处理新方法   总被引:1,自引:0,他引:1  
为了保证新鲜水果和蔬菜中的农药残留在法定的最大残留允许限量以下,达到安全农产品的要求,农药残留分析的样品前处理至关重要,作者所用方法是在乙腈作为提取溶剂的多残留检测方法上发展起来的.该技术采用固相萃取代替传统的液一液萃取;用氮吹仪代替旋转蒸发仪,大大简化了样品前处理步骤,节约了时间,且回收率达到了农残检测技术要求.该方法能对有机磷,有机氯(包括拟除虫菊酯)和N-甲基氨基甲酸酯类农药分析准确定性、定量起到关键作用.  相似文献   
424.
本文采用气-液双膜模型和大连湾水文参数,对大连湾检测出的挥发性有机物的挥发速率常数进行估算。结果表明,三氯乙烯等14种挥发性有机物在大连湾海域中的挥发速率常数在8.0×10^-3h-1-1.4×10^-2×^-1之间,挥发半衰期在50h=80h之间。因此,挥发至大气是这些在机物主要归宿。  相似文献   
425.
Huang DJ  Wang SY  Chen HC 《Chemosphere》2004,57(11):1-1627
The purpose of this study was to investigate the effect of chlordane and lindane on morphological changes and endocrine disruption in male Green neon shrimp (Neocaridina denticulata). In this experiment, individuals of N. denticulata, a common inhabitant of freshwater systems in Taiwan, were exposed to chlordane (1 and 10 ng/l) and lindane (0.1 and 1 μg/l). Morphological changes and reproductive hormone levels were observed following four weeks exposure. According to our findings, an increase in estrogen, a reduction in testosterone, and morphological alternations of the masculine appendage were observed in both chlordane- and lindane-treated shrimp, while induction of a vitellogenin-like protein appeared only in shrimp treated with 10 ng/l chlordane. An endocrine disruption effect on N. denticulata was demonstrated, and may apply to other organochlorine pesticides or endocrine disruption chemicals.  相似文献   
426.
As part of the research project “information system for environmental chemicals” a factual databank on a testset of 68 chemicals was developed. The set-up of the databank is described and the analysis of the results is shown for benzo(k)fluoranthene using a graphical boxplot illustration.  相似文献   
427.
Background LCA is the only internationally standardized environmental assessment tool (ISO 14040-43) for product systems, including services and processes. The analysis is done ‘from cradle-to-grave’, i.e. over the whole life cycle. LCA is essentially a comparative method: different systems fulfilling the same function (serving the same purpose) are compared on the basis of a ‘functional unit’ - a quantitative measure of this function or purpose. It is often believed that LCA can be used for judging the (relative) sustainability of product systems. This is only partly true, however, since LCA is restricted to the environmental part of the triad ‘environment/ecology - economy - social aspects (including intergenerational fairness)’ which constitutes sustainability. Standardized assessment tools for the second and the third part are still lacking, but Life Cycle Costing (LCC) seems to be a promising candidate for the economic part. Social Life Cycle Assessment still has to be developed on the basis of known social indicators.Method and Limitations LCA is most frequently used for the comparative assessment or optimization analysis of final products. Materials and chemicals are difficult to analyse from cradle-to-grave, since they are used in many, often innumerable product systems, which all would have to be studied in detail to give a complete LCA of a particular material or substance! This complete analysis of a material or chemical is evidently only possible in such cases where one main application exists. But even if one main application does exist, e.g. in the case of surfactants (chemicals) and detergents (final products), the latter may exist in a great abundance of compositions. Therefore, chemicals and materials are better analysed ‘from cradle-to-factory gate’, leaving the analysis of the final product(s), the use phase and the ‘end-of-life’ phases to specific, full LCAs.Conclusion A comparative assessment of production processes is possible, if the chemicals (the same is true for materials) produced by different methods have exactly the same properties. In this case, the downstream phases may be considered as a ‘black box’ and left out of the assessment. Such truncated LCAs can be used for environmental comparisons, but less so for the (environmental) optimization analysis of a specific chemical: the phases considered as ‘black box’ and left out may actually be the dominant ones. A sustainability assessment should be performed at the product level and contain the results of LCC and social assessments. Equal and consistent system boundaries will have to be used for these life cycle tools which only together can fulfil the aim of assessing the sustainability of product systems.  相似文献   
428.
GOAL, SCOPE AND BACKGROUND: In 1998, the International Council of Chemical Associations (ICCA) launched a global initiative to investigate more than 1,000 HPV chemicals (High Production Volume, > or = 1,000 t/a) within the refocused OECD HPV Chemicals Programme. Up to the OECD SIDS Initial Assessment Meeting in April 2004 (SIAM 18) 147 ICCA dossiers (ca. 230 CAS-No) have been assessed based on a harmonised data set. The environmental profile and an ecotoxicological characterisation of these chemicals are presented here. Data for acute aquatic toxicity were correlated among each other, as well as data for fish (LC50, LD50) and rodents (LD50). The data for acute aquatic toxicity are compared with other existing chemicals. METHODS: Data of the ICCA HPV chemicals from the OECD SIAM 11-18 are presented for: log Kow (as an indicator for bioaccumulation potential), biodegradation, acute aquatic toxicity and availability of long-term toxicity data. Correlation analysis was performed with log transformed data and a linear regression model was fitted to the data, if a significant correlation was found. Acute toxicity for fish and acute oral toxicity for rodents were correlated on a molar basis. Acute aquatic toxicity of the chemicals is compared with data from BUA reports 1-234 and a random EINECS sample (Knacker et al. 1995). RESULTS AND DISCUSSION: According to the dossier information, 71 of the 147 ICCA chemicals are not 'readily biodegradable', 21 have a log Kow > or = 3, and 44 are 'toxic' (LC/EC50 < or = 10 mg/L) or 'very toxic' (LC/EC50 < or = 1 mg/L) to aquatic organisms. For 77, only the base set (acute fish, Daphnia and algae) is available, for the rest at least one long-term test (fish or Daphnia) is available and three tests for a mere 14 others. Based on the data presented, the SIAM gives recommendations for Environment and Human Health. 22 chemicals have been identified as a 'candidate for further work' for Environment and 16 for Human Health. The highest correlation coefficient was obtained correlating fish and Daphnia (r2 = 0.79). LC50 (fish) is significantly correlated with LD50 (rodent), but data are widely scattered. The correlation is not improved after transforming LC50 (fish) to LD50 (fish), using BCF QSAR. Based on acute aquatic toxicity, 25.1% of the chemicals from the BUA reports 1-234 are classified as 'very toxic' (LC/EC50 < or = 1 mg/L). This proportion is 2.5-fold higher than the ICCA HPV chemicals and 1.4-fold higher than the random EINECS sample. CONCLUSIONS: Correlation coefficients for aquatic toxicity data are rather uniform (0.57-0.79) compared with literature data, but also the best correlation was observed between fish and Daphnia. Because the scatter around the regression lines is still considerable, simple predictions of ecotoxicity between species are not possible. Correlation of LC50 (fish) and LD50 (rodent) indicates that toxicity is different. Surprisingly, the correlation of fish and rodent toxicity is not improved by transforming LC50 values to internal LD50s. The selection of ICCA chemicals by market significance (production volume) leads to a classification of toxicity, which is more comparable to a random sample of EINECS chemicals than to German BUA chemicals. The latter were chosen for concern (for Environment or Human Health). RECOMMENDATIONS AND OUTLOOK: Of 147 dossiers assessed between SIAM 11-18, ca. 75% were sponsored by the three following countries: Germany (42), USA (37) and Japan (33). The current output is about 50 dossiers per year (70-100 CAS-No), but a trend for an increase of output is noticeable. Industry, national authorities, and OECD work on a further development to speed up the output. The number of chemicals with 'low priority for further work' and the work recommended for the 'candidates' (mainly exposure assessment) indicate that the data presented were adequate for an initial hazard assessment according to OECD requirements. From the ICCA HPV list (n = 880, state of 1999) 44% of the chemicals have data available to cover all SIDS endpoints for Environment and only 33% for Human Health (Allanou et al. 1999). This indicates the importance of the Initiative to provide information on existing chemicals. The authors agree with the expectation "...that the scientific information provided by this global initiative will be considered as an internationally accepted and harmonised basis for further steps of chemicals management." (ICCA 2002 b).  相似文献   
429.
Selection of Bioindicators of Pollution for Marine Monitoring Programmes   总被引:1,自引:0,他引:1  
The ultimate management concerns related to toxic chemicals in the marine environment are for the magnitude and extent of biological effects, including those on human health, that may result. Over the past several years, the National Status and Trends (NS&T) Program of the US National Oceanic and Atmospheric Administration (NOAA) has supported the development and application of a number of bioeffects measurements, including biochemical indicators of contaminant exposure and of reproductive status in fish, prevalence of histopathological lesions, toxicity bioassays of sediments and water, and benthic community structural features. Some of these measurements have been applied as part of regular sampling at the nationwide network of NS&T sites, while others have been assessed in more intensive, regional studies. Our experience with different indicators is summarized and discussed in relation to a set of monitoring objectives and evaluation criteria. Current conclusions are: (a) iterative application of controlled laboratory experiments and field validation tests are required to verify causality and mechanisms of biological responses to contaminants; (b) contaminant concentrations, indicator species, and local conditions vary considerably in different areas and at different times, requiring the use of different effects measurements oriented toward specific objectives and hypotheses; and (c) tiered, sequential application of a mix of indicators, including direct measurements on indigenous organisms and indirect bioassay approaches, is useful and effective for estimating the magnitude and spatial extent of contaminant bioeffects.  相似文献   
430.
从加强危险化学品安全人才体系建设来提高危险化学品安全管理水平的角度出发.针对安全监管人才队伍、企业安全人才队伍,以及安全中介机构人才队伍3个方面,分析了我国危化品安全人才的现状、存在的不足,并提出了加强安全人才队伍体系建设的具体措施建议。  相似文献   
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