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de Andrade Brito I Arruda Freire C Yamamoto FY Silva de Assis HC Rodrigues Souza-Bastos L Cestari MM de Castilhos Ghisi N Prodocimo V Filipak Neto F de Oliveira Ribeiro CA 《Journal of environmental monitoring : JEM》2012,14(2):615-625
Paraíba do Sul River is located at a very densely inhabited region of Brazil crossing the three most industrialized states of the country (S?o Paulo, Minas Gerais and Rio de Janeiro states). As a result, industrial and farming residues as well as urban sewage are frequently disposed without appropriate treatment. The current study aimed at investigating the water quality in three reservoirs along the Paraíba do Sul River (Ilha dos Pombos, Santa Cecília and Santa Branca), through physiological, morphological, biochemical, and genetic biomarkers. The bioindicator chosen was the catfish Pimelodus maculatus, sampled during the dry (June 2008) and rainy (February 2009) seasons. Also, some water physicochemical parameters were analyzed from the sampling sites, but displayed no alterations according to the Brazilian Agency for Water Quality Legislation. Branchial carbonic anhydrase activity was inhibited in the dry season, while renal carbonic anhydrase activity was inhibited in the rainy season in the Santa Branca reservoir, indicating disturbance of osmoregulatory and acid-base regulation processes. Histopathological alterations were observed in the gills (neoplasic and tissue hyperplasia processes) and liver (necrosis), indicating serious damage to the functional integrity of these organs. A high incidence of melanomacrophage centers was observed in the liver, suggesting an intense immune response in all reservoirs. Acetylcholinesterase and catalase activity showed also differences corroborating some morphological results. Likewise, the induction of the micronucleus and DNA damage indicate genotoxicity, but mainly in the Santa Branca reservoir. Thus, the health status of P. maculatus warrants caution in the use of the water from the 3 reservoirs for direct human consumption, particularly after the accidental spill of endosulfan in November 2008, three months before the rainy season sampling. 相似文献
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Nédia de Castilhos Ghisi Marta Margarete Cestari 《Environmental monitoring and assessment》2013,185(4):3201-3207
The glyphosate-based herbicide, Roundup®, is one of the most used pesticides worldwide. In concert with the advent of transgenic crops resistant to glyphosate, the use of this pesticide has led to an increase in agricultural yields. The objective of this study was to evaluate the genotoxic effect that the herbicide Roundup® (at a concentration of 6.67 μg/L, corresponding to 3.20 μg/L glyphosate) can have on the fish Corydoras paleatus. Treatment groups were exposed for 3, 6, and 9 days, and effects were analyzed using the piscine micronucleus test (PMT) and comet assay. A group subjected to filtered water only was used as a negative control. The PMT did not show differences between the control and exposed groups for any of the treatment times. In contrast, the comet assay showed a high rate of DNA damage in group exposed to Roundup® for all treatment times, both for blood and hepatic cells. We conclude that for the low concentration used in this research, the herbicide shows potential genotoxic effects. Future research will be important in evaluating the effects of this substance, whose presence in the environment is ever-increasing. 相似文献
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Flávio Henrique Tincani Osório Luis Felipe Oliveira Silva Laercio Dante Stein Piancini Ana Carolina Barni Azevedo Samuel Liebel Flavia Yoshie Yamamoto Vivian Prá Philippi Marcos Leandro Silva Oliveira Claudia Feijó Ortolani-Machado Francisco Filipak Neto Marta Margarete Cestari Helena Cristina da Silva de Assis Ciro Alberto de Oliveira Ribeiro 《Environmental science and pollution research international》2014,21(15):9145-9160
The Tubarão River rises in Santa Catarina, Brazil, and has been historically affected by coal mining activities around its springhead. To evaluate its water conditions, an investigation regarding a possible decontamination gradient associated with the increased river flow toward the estuary, as well as the influence of seasonality over this gradient was performed through a series of biomarkers (vitellogenin, comet assay, lipid peroxidation, protein carbonylation, gluthatione, gluthatione S-transferase, acetylcholinesterase, light microscopy in liver, and scanning electron microscopy in gills) and chemical analysis (polycyclic aromatic hydrocarbons (PAHs) in bile and metal analysis in sediment) in the cichlid Geophagus brasiliensis. Two collections (summer and winter) were made in four distinct sites along the river, while sediments were sampled between those seasons. As expected, the contamination linked exclusively to mining activities was not observed, possibly due to punctual inputs of contaminants. The decontamination gradient was not observed, although seasonality seemed to have a critical role in the responses of biomarkers and availability of contaminants. In the summer, the fish presented higher histopathological damages and lower concentrations of PAHs, while in the winter they showed both higher genetic damage and accumulation of PAHs. The Tubarão suffers impacts from diverse activities, representing health risks for wild and human populations. 相似文献
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Totsche O Fyson A Kalin M Steinberg CE 《Environmental science and pollution research international》2006,13(4):215-224
Background, Aims and Scope The acidification of mine waters is generally caused by metal sulfide oxidation, related to mining activities. These waters
are characterized by low pH and high acidity due to strong buffering systems. The standard acidity parameter, the Base Neutralization
Capacity (BNC) is determined by endpoint titration, and reflects a cumulative parameter of both hydrogen ions and all buffering
systems, but does not give information on the individual buffer systems. We demonstrate that a detailed interpretation of
titration curves can provide information about the strength of the buffering systems. The buffering systems are of importance
for environmental studies and treatment of acidic mining waters.
Methods Titrations were carried out by means of an automatic titrator using acidic mining waters from Germany and Canada. The curves
were interpreted, compared with each other, to endpoint titration results and to elemental concentrations contained therein.
Results and Discussion The titration curves were highly reproducible, and contained information about the strength of the buffer systems present.
Interpretations are given, and the classification and comparison of acidic mining waters, by the nature and strength of their
buffering systems derived from titration curves are discussed. The BNC-values calculated from the curves were more precise
than the ones determined by the standard endpoint titration method. Due to the complex buffer mechanisms in acidic mining
waters, the calculation of major metal concentrations from the shape of the titration curve resulted in estimates, which should
not be confused with precise elemental analysis results.
Conclusion Titration curves provide an inexpensive, valuable and versatile tool, by which to obtain sophisticated information of the
acidity in acidic water. The information about the strength of the present buffer systems can help to understand and document
the complex nature of acidic mining water buffer systems. Finally, the interpretation of titration curves could help to improve
treatment measurements and the ecological understanding of these acidic waters. 相似文献
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Dehalogenation of trichloroethene (TCE) in the aqueous phase, either on palladium catalysts with hydrogen as the reductant or on metallic iron, was associated with strong changes in delta13C. In general, the delta13C of product phases were more negative than those of the parent compound and were enriched with time and fraction of TCE remaining. For dehalogenation with iron, the delta13C of TCE and products varied from -42/1000 to +5/1000. For the palladium experiments, the final product, ethane, reached the initial delta13C of TCE at completion of the dehalogenation reaction. During dehalogenation, the carbon isotope fractionation between TCE and product phases was not constant. The variation in delta13C of TCE and products offers a new monitoring tool that operates independently of the initial concentration of pollutants for abiotic degradation processes of TCE in the subsurface, and may be useful for evaluation of remediation efficiency. 相似文献
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The distinctive isotopic signature of plant-derived chloromethane: possible application in constraining the atmospheric chloromethane budget 总被引:2,自引:0,他引:2
Chloromethane (CH(3)Cl) is the most abundant halocarbon in the atmosphere. Although largely of natural origin it is responsible for around 17% of chlorine-catalysed ozone destruction. Sources identified to date include biomass burning, oceanic emissions, wood-rotting fungi, higher plants and most recently tropical ferns. Current estimates reveal a shortfall of around 2 million ty(-1) in sources versus sinks for the halocarbon. It is possible that emissions from green plants have been substantially underestimated. A potentially valuable tool for validating emission flux estimates is comparison of the delta13C value of atmospheric CH(3)Cl with those of CH(3)Cl from the various sources. Here we report delta13C values for CH(3)Cl released by two species of tropical ferns and show that the isotopic signature of CH(3)Cl from pteridophytes like that of CH(3)Cl from higher plants is quite different from that of CH(3)Cl produced by biomass burning, fungi and industry. delta13C values for CH(3)Cl produced by Cyathea smithii and Angiopteris evecta were respectively -72.7 per thousand and -69.3 per thousand representing depletions relative to plant biomass of 42.3 per thousand and 43.4 per thousand. The characteristic isotopic signature of CH(3)Cl released by green plants should help constrain their contribution to the atmospheric burden when reliable delta13C values for all other major sources of CH(3)Cl are obtained and a globally averaged delta13C value for atmospheric CH(3)Cl is available. 相似文献
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