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1.
Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l−1 range, some active metabolites could be present at higher concentrations, although limited data on metabolism and environmental fate limit the relevance of PECs. The biological effects are not expected to be restricted to progestagenic activity. Both anti-androgenic activity (mainly for cyproterone acetate, chlormadinone acetate and their metabolites) and estrogenic activity (mainly for reduced metabolites of levonorgestrel and norethisterone) should also occur. All these molecules are likely to have a cumulative effect among themselves or with other xenoestrogens. Studies on occurrence, toxicity and degradation time are therefore needed for several of these compounds.  相似文献   

2.
Toxicological assessment of chlorinated diphenyl ethers in the rat   总被引:1,自引:0,他引:1  
Chlorinated diphenyl ethers are environmental contaminants that have been found in Great Lakes fish and birds. Because of their presence in the food chain, and potential for human exposure, the present short-term study was conducted to assess their toxicity. Groups of 10 male and 10 female rats were each given by gavage 2,2',4,4'6-pentachlorodiphenyl ether (CDE1), 2,2',4,4',5,6-hexachlorodiphenyl ether (CDE2) or 2,2',3,3',4,6'-hexachlorodiphenyl ether (CDE3) at dose levels of 0.04, 0.4, 4.0 or 40 mg/kg b.w./day for a period of 28 days. The control group received an equivalent volume of corn oil only (0.5 ml/100 g b.w.). Treatment with the three CDE congeners did not result in suppression of growth rate or food consumption. Increased liver weights were seen in the animals of both sexes fed 40 mg/kg CDE2, in males treated with 40 mg/kg CDE1, and in females with 40 mg/kg CDE3. Hepatic microsomal aminopyrine demethylase activity was significantly higher in the male rats administered 40 mg/kg CDE2, and aniline hydroxylase activity was elevated in the females following the same treatment. Serum glucose, calcium, protein and urea nitrogen of CDE1-treated males were higher than the control. Levels of uric acid, potassium and LDH of CDE3-treated females were also elevated. No hematological changes were observed. Histological examination revealed that the liver and thyroid were the target organs affected by CDE treatment but the morphological changes were mild even at the highest dose level. Changes in the liver consisted of nuclear vesiculation and increased cytoplasmic volume. Alterations in the thyroid were characterized by increased epithelial height and follicular collapse. Based on the data presented above, the 3 CDE congeners can only be considered moderately toxic in the rat.  相似文献   

3.
Abstract

Chlorinated diphenyl ethers are environmental contaminants that have been found in Great Lakes fish and birds. Because of their presence in the food chain, and potential for human exposure, the present short‐term study was conducted to assess their toxicity. Groups of 10 male and 10 female rats were each given by gavage 2,2’,4,4'6‐pentachlorodiphenyl ether (CDE1), 2,2’,4,4’,5,6‐hexachlorodiphenyl ether (CDE2) or 2,2’,3,3’,4,6'‐hexachlorodiphenyl ether (CDE3) at dose levels of 0.04, 0.4, 4.0 or 40 mg/kg b.w./day for a period of 28 days. The control group received an equivalent volume of corn oil only (0.5 ml/100 g b.w.). Treatment with the three CDE congeners did not result in suppression of growth rate or food consumption. Increased liver weights were seen in the animals of both sexes fed 40 mg/kg CDE2, in males treated with 40 mg/kg CDE1, and in females with 40 mg/kg CDE3. Hepatic microsomal aminopyrine demethylase activity was significantly higher in the male rats administered 40 mg/kg CDE2, and aniline hydroxylase activity was elevated in the females following the same treatment. Serum glucose, calcium, protein and urea nitrogen of CDE1‐treated males were higher than the control. Levels of uric acid, potassium and LDH of CDE3‐treated females were also elevated. No hematological changes were observed. Histological examination revealed that the liver and thyroid were the target organs affected by CDE treatment but the morphological changes were mild even at the highest dose level. Changes in the liver consisted of nuclear vesiculation and increased cytoplasmic volume. Alterations in the thyroid were characterized by increased epithelial height and follicular collapse. Based on the data presented above, the 3 CDE congeners can only be considered moderately toxic in the rat.  相似文献   

4.
5.
Eighty samples of sandy substrate were collected in November 2002 and 2003, from 20 municipal playgrounds in Madrid (Spain) to assess the potential adverse health effects of the exposure of children to trace elements in this material during their games. In each playground, two 500 g samples were collected, dried at 45 degrees C for 48 h, sieved below 100 microm, acid digested and analyzed by ICP-MS. Doses contacted through ingestion and inhalation and the dose absorbed through the skin were calculated using USEPAs hourly exposure parameters for children and the results of an in situ survey. The toxicity values considered in this study were mostly taken from the US DoEs RAIS compilation. The results of the risk assessment indicate that the highest risk is associated with ingestion of soil particles and that the trace element of most concern is arsenic, the exposure to which results in a cancer risk value of 4.19 x 10(-6), close to the 1 x 10(-5) probability level deemed unacceptable by most regulatory agencies. Regarding non-cancer effects, exposure to playground substrate yields an aggregate Hazard Index of 0.28, below the threshold value of 1 (with As, again, as the largest single contributor, followed by Pb, Cr, Al and Mn). Although the uncertainties associated with the estimates of toxicity values and exposure factors should be reduced before any definite conclusions regarding potential health effects are drawn, risk assessment has proven to be a very useful tool to identify the contaminants and exposure pathways of most concern in urban environments.  相似文献   

6.
Chlorinated diphenyl ethers (CDE's) are environmental contaminants that have been found in Great Lakes fish. Because of the paucity of toxicity data and potential for human exposure, the present short-term study was conducted to assess their potential toxic effects. Groups of 10 male and 10 female rats were administered the three CDE congeners (2,2',4,4',5-pentachlorodiphenyl ether (PCDE), 2,2',4,4',5,5'-hexachlorodiphenyl ether (HCDE), 2,2',3,4,4',6,6'-heptachlorodiphenyl ether (HPCDE] in diets at levels of 0.5, 5.0, 50 or 500 ppm for a period of 4 weeks. Decreased food consumption was observed with male and female rats fed the diet containing 500 ppm HPCDE. Treatment with the three isomers at the highest dose level produced an increase in liver weight in both sexes. While administration of PCDE produced an increase in hepatic aminopyrine demethylase activity, HCDE caused a significant increase in aminopyrine demethylase, aniline hydroxylase and ethoxyresorufin de-ethylase activities. HPCDE caused a significant increase in ethoxyresorufin de-ethylase activity. HPCDE at the highest dose level also caused a significant reduction in circulating lymphocytes in male rats. The 3 CDE's produced mild and adaptative histological changes in the liver and thyroid, but only HPCDE elicited mild changes in the thymus, bone marrow, and spleen. The above data indicate that HPCDE is immunosuppressive and that all three CDE isomers are considered to be moderately toxic in rats. The no-observable effects levels appear to be between 5-50 ppm in diet (0.36-3.0 mg/kg b.w.) for the three CDE's.  相似文献   

7.
8.
Traditional single species toxicity tests and multiple component laboratory-scaled microcosm assays were combined to assess the toxicological hazard of diesel oil, a model complex mixture, to a model aquatic environment. The immediate impact of diesel oil dosed on a freshwater community was studied in a model pond microcosm over 14 days: a 7-day dosage and a 7-day recovery period. A multicomponent laboratory microcosm was designed to monitor the biological effects of diesel oil (1.0 mg litre(-1)) on four components: water, sediment (soil + microbiota), plants (aquatic macrophytes and algae), and animals (zooplanktonic and zoobenthic invertebrates). To determine the sensitivity of each part of the community to diesel oil contamination and how this model community recovered when the oil dissipated, limnological, toxicological, and microbiological variables were considered. Our model revealed these significant occurrences during the spill period: first, a community production and respiration perturbation, characterized in the water column by a decrease in dissolved oxygen and redox potential and a concomitant increase in alkalinity and conductivity; second, marked changes in microbiota of sediments that included bacterial heterotrophic dominance and a high heterotrophic index (0.6), increased bacterial productivity, and the marked increases in numbers of saprophytic bacteria (10 x) and bacterial oil degraders (1000 x); and third, column water acutely toxic (100% mortality) to two model taxa: Selenastrum capricornutum and Daphnia magna. Following the simulated clean-up procedure to remove the oil slick, the recovery period of this freshwater microcosm was characterized by a return to control values. This experimental design emphasized monitoring toxicological responses in aquatic microcosm; hence, we proposed the term 'toxicosm' to describe this approach to aquatic toxicological hazard evaluation. The toxicosm as a valuable toxicological tool for screening aquatic contaminants was demonstrated using diesel oil as a model complex mixture.  相似文献   

9.
中国废旧轮胎利用途径的环境影响评价   总被引:1,自引:0,他引:1  
运用生命周期评价方法,比较了中国废旧轮胎4种利用途径(常温生产60目胶粉、动态脱硫生产再生胶、微负压热裂解、土法炼油)的环境影响。结果表明,根据环境影响(以生态指数表征),中国废旧轮胎利用途径的优先度排序为微负压热裂解常温生产60目胶粉动态脱硫生产再生胶土法炼油。其中,前3种利用途径产生的环境影响主要是由燃料生产过程产生的间接环境影响构成。  相似文献   

10.
Environmental Science and Pollution Research - Trihalomethanes (THMs) are common disinfection by-products in chlorinated tap waters. They can cause various cancers and non-cancer health hazards....  相似文献   

11.
针对目前粉尘危害评价存在的不足,采用最优权法确定各评价指标的权系数,利用模糊识别技术对粉尘危害程度进行综合评价,初步建立了粉尘危害评价指标体系和评价分级标准.结合某矿山实例,对粉尘危害进行模糊综合评价.评价结果表明,模糊综合识别技术能够较好反应实际情况,是一种有效的评价方法,对粉尘防治工作具有一定的指导意义.  相似文献   

12.
The gold nanoparticles (Au-NPs) are being increasingly used because of their huge diversity of applications, and consequently, elevated levels in the environment are expected. However, due to their physico-chemical properties and functionalization a high variety of Au-NPs can be found, and complete toxicological information for each type of Au-NPs still lacks, and even, the toxicological information for the same species is sometimes contradictory. Therefore, hazard assessment should be done case by case. Hence, the objective of this study was to obtain ecotoxicological information of the same Au-NPs in aquatic organisms and to find a rationale for Au-NPs toxicity. For such a purpose, bare and hyaluronic acid capped Au-NPs (12.5 nm) along with Au-NPs bulk material were tested on freshwater algae, Daphnia and zebrafish. Results showed that while gold nanoparticles were found to be harmless to the tested organisms, the soluble gold showed to be toxic to algae and Daphnia, with an LC50 between 1 and 2 mg L−1. Comparing our results with those gathered in the literature, it appears that a common hazard assessment of Au-NPs on the studied organisms can be elucidated.  相似文献   

13.
Many kinds of cosmetic products were analyzed to determine gross radioactivity. In this study, gross alpha/beta radioactivity concentrations in 51 cosmetic samples were determined. The examined cosmetic products consist of blusher, eye shadow, lipstick, nail polish, shampoo, hand cream, cellulite cream, baby powder, soap, and toothpaste. The gross alpha–beta activity concentrations were measured with a nuclear spectroscopic system which contains gas-flow proportional counters. The highest gross alpha/beta activity concentrations were found in eye shadow samples of 1.621Bq g?1 for alpha and 6.471Bq g?1 for beta. The total effective doses due to gross radioactivity for skin were calculated. Although the effective dose of eye shadow samples had the highest value, the effective doses due to gross radioactivity concentrations in this study were found to be lower than the radiological limits given by the authorities.  相似文献   

14.
This paper starts by investigating the rationales for public participation in environmental assessment. It is contended that access to participation may refer both to means as well as ends; thus, some advocates of citizen participation favour involvement for social and or political reasons (i.e. the participation is the end in itself). However, the value of that participation may also, as we shall see, advance quality and depth of knowledge (i.e. the participation is viewed only as a means to an end). The initial two sections, therefore, paint two broad brushstrokes: the first concerns why we should require public participation, and the second why that participation may improve the quality of our environmental assessment procedure. Further, it is then argued that the issues and problems of public participation vary across different environmental issues and also vary across different stages of the environmental assessment procedure and according to the scientific disciplines and practices involved. This paper points the way towards an open and representative style in which communities are included in environment assessment processes as a source of new or better knowledge, as well as a contribution towards what the EU refers to as the 'horizontal participatory approach'. The paper briefly considers methodological issues concerning ways in which participation might be carried out.  相似文献   

15.
Short-term 48, 72 and 96-h aquatic toxicity tests were conducted to evaluate the acute toxicity of eight fluorinated acids to the cladoceran, Daphnia magna, the green alga, Pseudokirchneriella subcapitata, and the rainbow trout, Oncorhynchus mykiss or the fathead minnow, Pimephales promelas. The eight fluorinated acids studied were tridecafluorohexyl ethanoic acid (6:2 FTCA), heptadecafluorooctyl ethanoic acid (8:2 FTCA), 2H-dodecafluoro-2-octenoic acid (6:2 FTUCA), 2H-hexadecafluoro-2-decenoic acid (8:2 FTUCA), 2H,2H,3H,3H-undecafluoro octanoic acid (5:3 acid), 2H,2H,3H,3H-pentadecafluoro decanoic acid (7:3 acid), n-perfluoropentanoic acid (PFPeA) and n-perfluorodecanoic acid (PFDA). The results of the acute toxicity tests conducted during this study suggest that the polyfluorinated acids, 8:2 FTCA, 8:2 FTUCA, 6:2 FTCA, 6:2 FTUCA, 7:3 acid and 5:3 acid, and the perfluorinated acids PFPeA and PFDA, are generally of low to medium concern based on evaluation of their acute freshwater toxicity (EC/LC50s typically between 1 and >100 mg L−1) using the USEPA TSCA aquatic toxicity evaluation paradigm. For the polyfluorinated acids, aquatic toxicity generally decreased as the number of fluorinated carbons decreased and as the overall carbon chain length decreased from 12 to 8. Acute aquatic toxicity of the 5 and 10 carbon perfluorocarboxylic acids (EC/LC50s between 10.6 and >100 mg L−1) was greater or similar to that of the 6-9 carbon perfluorocarboxylic acids (EC/LC50s > 96.5 mg L−1). This study also provides the first report of the acute aquatic toxicity of the 5:3 acid (EC/LC50s of 22.5 to >103 mg L−1) which demonstrated less aquatic toxicity than the 7:3 acid (EC/LC50s of 0.4-32 mg L−1). The cladoceran, D. magna and the green alga, P. subcapitata had generally similar EC50 values for a given substance while fish were typically equally or less sensitive with the exception that PFPeA was most toxic to fish. Predicted no-effect concentrations (PNECs) were estimated using approaches consistent with REACH guidance and when compared with available environmental concentrations, these PNECs suggest that the fluorinated acids tested pose little risk for aquatic organisms.  相似文献   

16.
This review summarizes the existing knowledge on the occurrence of tire wear particles in the environment, and their ecotoxicological effects. A meta-analysis on tire components in the environment revealed that tire wear particles are present in all environmental compartments, including air, water, soils/sediments, and biota. The maximum Predicted Environmental Concentrations (PECs) of tire wear particles in surface waters range from 0.03 to 56 mg l−1 and the maximum PECs in sediments range from 0.3 to 155 g kg−1 d.w. The results from our previous long-term studies with Ceriodaphnia dubia and Pseudokirchneriella subcapitata were used to derive Predicted No Effect Concentrations (PNECs). The upper ranges for PEC/PNEC ratios in water and sediment were >1, meaning that tire wear particles present potential risks for aquatic organisms. We suggest that management should be directed towards development and production of more environmentally friendly tires and improved road runoff treatment.  相似文献   

17.
Ecotoxicity data with high reliability and relevance are needed to guarantee the scientific quality of environmental risk assessments of pharmaceuticals. The main advantages of a more structured approach to data evaluation include increased transparency and predictability of the risk assessment process, and the possibility to use non-standard data.In this collaboration, between the research project MistraPharma and the German Federal Environment Agency, a new set of reporting and evaluation criteria is presented and discussed. The new criteria are based on the approaches in the literature and the OECD reporting requirements, and have been further developed to include both reliability and relevance of test data.Intended users are risk assessors and researchers performing ecotoxicological experiments, but the criteria can also be used for education purposes and in the peer-review process for scientific papers. This approach intends to bridge the gap between the regulator and the scientist’s needs and way of work.  相似文献   

18.
论中国环境影响评价中公众参与的一般模式   总被引:10,自引:0,他引:10  
公众参与在环境影响评价中的作用是不可替代的,并成为各国环评的基本内容.环评中公众参与的一般模式包括公众享有环境知情权和参与决策权、合适的公众参与的主体范围、明确的公众参与环评的程序和方法以及公众参与环评的保障机制.为更好地发挥环评的作用,应当从实体和程序两方面对法规加以完善.还应在信息公开、立法的完善和配套制度的建立等方面完善环评中的公众参与制度.  相似文献   

19.
The diagnostic capability of changes in the benthic macroinvertebrate community composition to determine the cause in contaminated sediments were addressed using box core mesocosms subjected to cadmium, atrazine and nutrient enrichment. Intact cores of lake sediment were collected from Lake Erie at four occasions during 1996 and were returned to laboratory where they were maintained and manipulated. The benthic community composition of the artificially polluted mesocosms was compared with field data, collected at the same time as the intact cores, and to untreated control boxes. Community composition was related to the measured environmental variables using multi-dimensional scaling (MDS) and principle axis correlation (PCC). Community responses to different treatments were both different and consistent, suggesting that the community structure of these mesocosms could be used to identify the primary source of impact.  相似文献   

20.
Spatial distribution and hazard assessment of soil lead in the mining site of Silvermines, Ireland, were investigated using statistics, geostatistics and geographic information system (GIS) techniques. Positively skewed distribution and possible outlying values of Pb and other heavy metals were observed. Box-Cox transformation was applied in order to achieve normality in the data set and to reduce the effect of outliers. Geostatistical analyses were carried out, including calculation of experimental variograms and model fitting. The ordinary point kriging estimates of Pb concentration were mapped. Kriging standard deviations were regarded as the standard deviations of the interpolated pixel values, and a second map was produced, that quantified the probability of Pb concentration higher than a threshold value of 1000 mg/kg. These maps provide valuable information for hazard assessment and for decision support.  相似文献   

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