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101.
The increased pollution in ecosystems reinforces the importance of both chemical monitoring and biological monitoring of streams and rivers, as an effective water quality-based approach to assess aquatic ecosystem health. In this study, gudgeon (Gobio gobio) and mullet (Mugil cephalus) liver histopathology (biomarker) and some macroinvertebrate community indexes and metrics (bioindicator) were used to evaluate the effect of the wastewater treatment plant (WWTP) of Febros (Avintes) in Febros River water quality and ecosystem health. Regarding macroinvertebrate communities, the Belgian Biotic Index (BBI) and Iberian Biological Monitoring Working Party (IBMWP) indexes suggested that Febros water was slightly polluted, even though the worst situation was found downstream the WWTP discharge. Concerning community metrics, upstream percent of individuals in five numerically dominant taxa (80%) was slightly more superior than the downstream (78%). The presence of intolerant or sensible individuals, determined by percent of Ephemeroptera, Plecoptera, and Trichoptera individuals and number of Ephemeroptera, Plecoptera, and Trichoptera families metrics, was higher upstream WWTP, reflecting a better water quality. The histopathology shows the presence of hepatic lesions in gudgeon and mullet. The statistical analysis of the lesion gradation showed that only necrosis was significantly higher in gudgeon captured downstream the WWTP, while differences were not observed for mullet. The multivariate analysis of data confirmed the existence of differences in hepatic lesions between gudgeon and mullet and between sampling sites. Regarding macroinvertebrate community, this analysis showed that the organic contamination reflected by the BBI and IBMWP indexes values was a determinant factor in the spatial distribution of macroinvertebrates. This work showed that the study of different biological organization levels can be used for a better assessment of ecosystem ecological integrity and can be used as a tool to reveal anthropogenic activity effects in macroinvertebrate diversity and in fish liver pathology from Febros River.  相似文献   
102.
In 1997, the Polychlorinated dibenzo-para-dioxin (PCDD)/Polychlorinated dibenzofuran (PCDF) concentrations in dairy products in Germany and other European countries increased. The PCDD/PCDF source was contaminated lime used in Brazilian citrus pulp pellets. The contaminated lime was mined from an industrial dump site. However, the detailed origin of the PCDD/PCDFs in the lime was not revealed. This paper investigates the contamination origin and describes the link between lime milk from the dumpsite of a chlorine/organochlorine industry and the contaminated lime. The contaminated lime stem from mining at the corporate landfill of Solvay Indupa in Sao Paulo. The landfill was used for 40 years for deposition of production residues and closed in 1996. The factory operated/operates at least two processes with potentially high PCDD/PCDFs releases namely the oxychlorination process for production of ethylene dichloride (EDC) and the chlor-alkali process. The main landfilled waste was lime milk (1.4 million tons) from the vinyl chloride monomer production (via the acetylene process) along with residues from other processes. The PCDD/PCDF fingerprint revealed that most samples from the chemical landfill showed an EDC PCDD/PCDF pattern with a characteristic octachlorodibenzofuran dominance. The PCDD/PCDF pattern of a Rio Grande sediment samples downstream the facility showed a chlor-alkali pattern with a minor impact of the EDC pattern. The case highlights that PCDD/PCDF- and persistent organic pollutants-contaminated sites need to be identified in a comprehensive manner as required by the Stockholm Convention (article 6) and controlled for their impact on the environment and human health. Landfill mining and reuse of materials from contaminated deposits should be prohibited.  相似文献   
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Past attempts to measure the economic consequences of ozone on agriculture have been based on limited plant science information. This paper reports on an economic assessment of ozone on U.S. agriculture using recent crop response data from the National Crop Loss Assessment Network (NCLAN). The results are derived from a U.S. agricultural sector model that includes major crop and livestock production as well as domestic consumption, livestock feeding and export uses. The economic effects of four hypothetical ambient ozone levels are investigated. The analysis Indicates that the benefits to society of moderate (25%) ozone reductions are approximately $1.7 billion. A 25% Increase in ozone pollution results in costs (negative benefits) of $2.1 billion. These estimates do not reflect compliance costs of achieving the ozone changes and hence are not net benefits.  相似文献   
106.
Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges, mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical contaminants and to determine if contaminant concentrations in the fish were a risk to wildlife that forage at these sites. Concentrations of dieldrin, total DDT, total PCBs, toxaphene, TCDD-EQ, cadmium, chromium, mercury, lead, selenium, and zinc exceeded toxicity thresholds to protect fish and piscivorous wildlife in samples from at least one site; most exceedences were for total PCBs, mercury, and zinc. Chemical concentrations in fish from the Mississippi River Basin exceeded the greatest number of toxicity thresholds. Screening level wildlife risk analysis models were developed for bald eagle and mink using no adverse effect levels (NOAELs), which were derived from adult dietary exposure or tissue concentration studies and based primarily on reproductive endpoints. No effect hazard concentrations (NEHC) were calculated by comparing the NOAEL to the food ingestion rate (dietary-based NOAEL) or biomagnification factor (tissue-based NOAEL) of each receptor. Piscivorous wildlife may be at risk from a contaminant if the measured concentration in fish exceeds the NEHC. Concentrations of most organochlorine residues and elemental contaminants represented no to low risk to bald eagle and mink at most sites. The risk associated with pentachloroanisole, aldrin, Dacthal, methoxychlor, mirex, and toxaphene was unknown because NOAELs for these contaminants were not available for bald eagle or mink. Risk differed among modeled species and sites. Our screening level analysis indicates that the greatest risk to piscivorous wildlife was from total DDT, total PCBs, TCDD-EQ, mercury, and selenium. Bald eagles were at greater risk to total DDT and total PCBs than mink, whereas risks of TCDD-EQ, mercury, and selenium were greater to mink than bald eagle.  相似文献   
107.
Febros river water was sampled weekly, during 35 successive weeks, and analyzed for microbiological (total coliforms, faecal coliforms, faecal streptococci and enterococci) and chemical-physical (ammonia and temperature) parameters. All microbiological parameters were highly correlated with each other and with ammonia, suggesting that the simultaneous determination of all variables currently in use in the evaluation of the microbiological quality of waters is probably redundant, and could be simplified, and that ammonia should be tested as a sentinel parameter of the microbiological pollution load of Febros river. From the strains isolated from positive tubes of the faecal coliforms test (multiple tube fermentation technique) and retested in this assay, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae subsp. pneumoniae strains were positive, indicating that the faecal coliforms test is not totally specific for Escherichia coli, and can detect other bacteria. Considering that these Klebsiella spp. are not necessarily of faecal origin, it was concluded that the faecal coliforms test can overestimate true faecal pollution. From the strains isolated from positive tubes of the faecal coliforms procedure, only Escherichia coli strains were clearly positive in the β-D-glucuronidase test. All other species were negative or very weakly positive, suggesting that the assay of the β-D-glucuronidase activity is less prone to false positives than the faecal coliforms test in the quantification of Escherichia coli in environmental waters.  相似文献   
108.
The personal exposure of children aged 9 – 11 years to particulate matter (PM10 and PM2.5) was carried out between January and September 1997 in the London Borough of Barnet. Personal sampling along with home, garden and classroom microenvironmental monitoring was completed for all ten children. Each child was monitored for five days during winter, spring and summer. All children completed daily time activity diaries to provide information on any potential activities that could influence their exposure to particulate matter. Each evening a household activity questionnaire was also completed by the parents. Personal Environmental Monitors were used to sample personal exposure to PM10 and PM2.5. Harvard Impactors were used for the microenvironmental sampling of both size fractions. The children's mean personal exposure concentrations for PM10 during winter, spring and summer were 72, 54 and 35 µg/m3 respectively and for PM2.5 22, 17 and 18 µg/m3 respectively. In order to determine the potential sources of particulate matter, analysis of the Teflon filters has been undertaken. The physical characteristics of the particles have been identified using Scanning Electron Microscopy. The relationships between personal exposure concentrations and the different microenvironments will be discussed.  相似文献   
109.
In this study, we propose a process making calcium carbonate and calcium sulfate and recovering absorbent using ammonia absorbent, carbon dioxide, and industrial waste. The main objective of this study is to confirm the possibility of carbon capture and utilization based on waste materials. We assumed desulfurization gypsum and construction waste (ready mixed concrete washing water, waste concrete, etc.) are CaSO4, Ca(OH)2, respectively. And concentration of simulated carbon dioxide gas was 15 vol% similar to flue gas. Calcium carbonate was produced by combination reaction between ionic CO2 in absorbent and metal ion in the solid waste. Experiments were conducted at normal temperature and pressure. Furthermore, the generated products were characterized by X-ray diffraction, and scanning electron microscope.  相似文献   
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