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1.
Bull Environ Contam Toxicol ; 99(2): 167-172, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28597086

RESUMO

The objective of this study was to assess metal exposure in the Mediterranean Pond Turtle (Mauremys leprosa) inhabiting a watercourse in an ancient mining district polluted by different metals ("Rambla de Las Moreras", southeastern Spain) and included in the Ramsar Convention. For this purpose, mercury (Hg), lead (Pb), copper (Cu), zinc (Zn) and cadmium (Cd) were analysed in blood samples from 42 M. leprosa healthy adults (27 males and 13 females). The highest median concentrations were found for Zn, followed by Cu, Pb, Hg and Cd (366, 33, 9, 0.83 and 0.14 µg/dL, respectively). Although the literature regarding toxic metals in freshwater turtles is relatively scarce, Pb may cause deleterious effects in our population. In general, males presented higher levels than females, which could be due to maternal transfer during egg formation. The significant correlations between Cu-Cd and Cu-Hg suggest the implication of an efficient mechanism of detoxification involving metallothioneins.


Assuntos
Monitoramento Ambiental , Metais Pesados/sangue , Mineração , Tartarugas/sangue , Poluentes Químicos da Água/sangue , Animais , Cádmio/análise , Cobre/análise , Feminino , Masculino , Mercúrio/análise , Metais Pesados/análise , Lagoas/química , Espanha , Zinco/análise
2.
J Hazard Mater ; 229-230: 390-7, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22771345

RESUMO

The generation and disposal level of thermal power plant ash in India is a challenging task. The conventional mode of dilute phase ash slurry (10-20% solids by weight) transport through pipelines being practiced in majority of these plants not only consumes huge amount of precious water and pumping energy but also causes serious environmental problem at the disposal site. The present study investigates the rheological and leaching characteristics of an Indian ash samples at high solids concentrations (>50% by weight) using sodium silicate as an additive. The flow behaviour of ash slurry in the concentration range of 50-60% by weight is described by a Bingham-plastic model. It was indicated that the addition of sodium silicate (0.2-0.6% of the total solids) could able to reduce both the slurry viscosity and the yield stress. The analysis of the ash samples for the presence of heavy metals such as Fe, Cd, Ni, Pb, Zn, Cu, Co, As and Hg were carried out following Hansen and Fisher procedure. The addition of sodium silicate affected the leaching characteristics of the ash samples over a period of 300 days resulting in the reduction of leaching of heavy metals.


Assuntos
Cinza de Carvão/análise , Poluentes Ambientais/análise , Metais Pesados/análise , Cinza de Carvão/química , Conservação de Recursos Energéticos , Poluentes Ambientais/química , Resíduos Industriais/análise , Metais Pesados/química , Reologia , Silicatos/química , Viscosidade
3.
Environ Monit Assess ; 166(1-4): 477-84, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19496009

RESUMO

Using an organism living in situ for monitoring is referred as passive monitoring. Lepraria lobificans Nyl., a leprose lichen growing naturally on monuments and buildings in the city Mandav in central India is used for passive monitoring of atmospheric metals. Seven metals (Cd, Cr, Ni, Al, Fe, Cu, and Zn) were analyzed. Samples collected from road site exhibit the maximum concentration of Fe, Cd, Cr, Ni, and Zn. Iron exhibit maximum accumulation both in lichen thallus and the substratum with mean values of 2,195.63 microg g(-1) dry weight. As compared with other growth form of lichens, L. lobificans exhibits the higher accumulation of Fe than foliose and fruticose lichens. On the basis of these results, it can be hypothesized that L. lobificans is an excellent accumulator of different metals. The statistical analysis applied to the element concentration between the metals as well as between the sites by analysis of variance found the difference to be significant at 1% and 5%, respectively. Student-Newman-Keuls test also shows significant difference for iron between the different metals.


Assuntos
Poluentes Atmosféricos/análise , Ascomicetos/química , Monitoramento Ambiental/métodos , Metais Pesados/análise , Cidades , Índia , Líquens/química
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