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41.
The current study investigated oxidative stress parameters (enzymes activities, metallothionein content and lipid peroxidation) in freshwater fish, Oreochromis niloticus, tilapia exposure to Monjolinho River (in 4 months of year: January, April, July and November). One critical site in Monjolinho River (site B) was assessed in comparison to a reference site (site A). Water pH and oxygen concentration was lower than that recommended by CONAMA (Brazilian National Environmental Committee), resolution 357/2005 for protection of aquatic communities, and ammonium and the metals Cu, Zn, Mn and Fe (on all months) concentrations were higher than the maximum concentration recommended. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were significantly decreased in liver and muscle in tilapia from Monjolinho River, throughout the year, in relation to reference except in gills that SOD activity increased. Glutathione S-transferase (GST) activity was significantly increased in liver of the tilapia from Monjolinho River in all sites, in relation to reference except in gills that GST activity increased in July and decreased in November, suggesting that GST activity could be induced to neutralize the pollutants toxicity. On the other hand, GST activity was significantly decreased in white muscle indicating a toxic effect of pollutants, resulting in a decreased ability of tilapia to perform defense reactions associated to GSTs. The decrease of catalase (CAT) activity in gills of the O. niloticus together with the increase of SOD activity, could explain the increased lipid peroxidation (LPO) level in this organ. Metallothionein levels in liver and gills were significantly high in all sites. Results indicate that the exposure to metals caused severe damage to tissues; despite the consensually assumed antioxidant induction as a sign of exposure to contaminants the effects seem in part to be mediated by suppression of antioxidant system with SOD, CAT and GPx as potential candidates for tissues toxicity biomarkers of pollutants. 相似文献
42.
Elizabeth A. Daly Cassandra E. Benkwitt Richard D. Brodeur Marisa N. C. Litz Louise A. Copeman 《Marine Biology》2010,157(9):1975-1987
Juvenile salmon exhibit high growth rates upon their arrival into the marine environment. Dietary changes from freshwater
and estuarine habitats to those derived from the marine environment may play an important role in ultimate adult survival.
We measured the total lipid and fatty acid (FA) composition of juvenile Chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), and 18 of their potential prey items sampled from coastal waters during their first few months at sea. Coho salmon had
significant reductions in their lipid content (% wet weight) between May and June, likely due to early marine growth. We did
not find a significant drop between May and June Chinook salmon lipid content, which may indicate an earlier ontogenetic selection
to marine prey that are higher in lipids and essential fatty acids (EFAs). Juvenile salmon ate prey of both high and low lipids.
Significant FA compositional changes occurred for both coho and Chinook salmon between May and June. In May, the FA profile
of juvenile salmon, especially coho salmon, did not resemble their prey items; however, in June, there was a strong correlation
between salmon and their common fish prey as determined by gut content analysis. Significant increases in the level of EFAs,
especially docosahexaenoic acid (DHA, 22:6n-3) accounted for the majority of the monthly differences in salmon tissue FA composition.
In order for juvenile salmon to adequately meet their physiological requirements, they may have adapted to select advantageous
prey with higher levels of EFAs, especially DHA, in order to rapidly increase their growth and ultimate survival. 相似文献
43.
Diane M. Perry Roberto Sanchez William H. Glaze Marisa Mazari 《Environmental management》1990,14(4):441-450
Foreign-owned industry in the form of assembly plants, termed maquiladora, has become very important in Mexico to the extent
that it represents the second largest source of foreign exchange and is a valuable source for employment and regional development.
The economic prosperity gained from the rapid growth of the maquiladora industry has been accompanied by increased environmental
and human health risks associated with generation of hazardous waste. Diversification of industry has resulted in the predomination
of those sectors that likely use hazardous substances. The Mexicali-Calexico border region was selected to demonstrate the
potential for environmental and health risks associated with the generation of hazardous waste. Estimates for the generation
of hazardous waste were obtained from 34 maquiladora plants in Mexicali, represented by the electronic and electrical equipment
and parts, mechanical and transportation equipment, and toys and sporting equipment sectors. Repeated detection of volatile
organic compounds in the New River at the US-Mexico border suggests that hazardous waste from the printed circuit board industry
in Mexicali is not being disposed of in a proper manner. Potential adverse health effects, such as carcinogenic and mutagenic
responses associated with the detected volatiles, are discussed. US and Mexico national legislation and the Binational Environmental
Agreement were examined for their adequacy to ensure proper management of hazardous waste generated by the maquiladora industry.
Environmental policy options are presented that focus on: (1) increased environmental accountability of US parent companies
for their maquiladora assembly plants in Mexico; and (2) more integration between US Customs and border states with the US
Environmental Protection Agency to improve the binational management of hazardous waste generated by the maquiladora industry. 相似文献
44.
Rosa Grau Isabel M. Martínez Sonia Agut Marisa Salanova 《International journal of occupational safety and ergonomics》2013,19(1):23-35
This paper studies safety attitudes, their relationship with safety training behaviour, and generalised self-efficacy. From a sociotechnical perspective, training programs might be used as a mechanism for enhancing attitudes, especially to improve safety and occupational health. Also, self-efficacy allows to enhance training effectiveness. The aim of this paper is to validate a safety attitude scale and to examine its relationship to safety training behaviour and self-efficacy in organisational settings. With data from 140 employees, results show a conceptually meaningful 3-factor solution. Hier-archical multiple regression analysis shows a main effect of safety training behaviour and levels of self-efficacy on safety attitude. Study limitations and its implications on safety training design are also discussed. 相似文献
45.
Christiane D. Vitzthum von Eckstaedt Marisa Ioppolo-ArmaniosDavid Kelly Mark Gibberd 《Chemosphere》2012,89(11):1407-1413
This study presents carbon (δ13C) and hydrogen (δD) isotope values of volatile organic compounds (VOCs) in various emission sources using thermal desorption-gas chromatography-isotope ratio mass spectrometry (TD-GC-irMS). The investigated VOCs ranged from C6 to C10. Samples were taken from (i) car exhaust emissions as well as from plant combustion experiments of (ii) various C3 and (iii) various C4 plants. We found significant differences in δ values of analysed VOCs between these sources, e.g. δ13C of benzene ranged between (i) −21.7 ± 0.2‰, (ii) −27.6 ± 1.6‰ and (iii) −16.3 ± 2.2‰, respectively and δD of benzene ranged between (i) −73 ± 13‰, (ii) −111 ± 10‰ and (iii) −70 ± 24‰, respectively. Results of VOCs present in investigated emission sources were compared to values from the literature (aluminium refinery emission). All source groups could be clearly distinguished using the dual approach of δ13C and δD analysis. The results of this study indicate that the correlation of compound specific carbon and hydrogen isotope analysis provides the potential for future research to trace the fate and to determine the origin of VOCs in the atmosphere using thermal desorption compound specific isotope analysis. 相似文献
46.
47.
Valentina Ciardelli Nicola Rizzo Antonio Farina Marisa Vitarelli Paola Boni Luciano Bovicelli 《黑龙江环境通报》2001,21(7):586-588
The relationship between fetal renal function (FRF) and fetal serum beta2-microglobulin (B2MG) was investigated by comparing its value in 112 unaffected fetuses with that of 23 fetuses presenting with urinary tract malformations (UTM). Fetal serum level of B2MG was totally unrelated to gestational age; its value increased in cases of severe impairment of FRF but was similar to controls in all mild uropathies (p<0.05). Evaluating serum B2MG could be beneficial in fetuses with severe renal damage, but is of no use in unilateral UTM since only the global FRF is tested and not the function of each single kidney. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
48.
Ferreira MI Domingos M Gomes Hde A Saldiva PH de Assunção JV 《Environmental pollution (Barking, Essex : 1987)》2007,146(1):219-224
We report seasonal variation in CH(4) and N(2)O emission rate from solid storage of bovine manure in Delhi as well as emission factors and emission inventory from manure management systems in India. Emission flux observed in the year 2002-2003 was 4.29+/-1, 4.84+/-2.44 and 12.92+/-4.25 mg CH(4)kg(-1)dung day(-1), as well as 31.29+/-4.93, 72.11+/-16.22 and 6.39+/-1.76 microgN(2)O kg(-1)dung day(-1) in winter, summer and rainy seasons, respectively. CH(4) emission factors varied from 0.8 to 3.3 kg hd(-1)year(-1) for bovines and were lower than IPCC-1996 default values. N(2)O emission factors varied from 3 to 11.7 mg hd(-1)year(-1) from solid storage of manure. Inventory estimates were found to about 698+/-27 Gg CH(4) from all manure management systems and 2.3+/-0.46 tons of N(2)O from solid storage of manure for the year 2000. 相似文献
49.
Marisa Casale Scott Drimie Timothy Quinlan Gina Ziervogel 《Regional Environmental Change》2010,10(2):157-168
Within southern Africa, many households are facing increasing pressures as they deal with multiple challenges such as low
employment, high levels of disease, environmental resources under pressure and changing political landscapes. To respond to
the needs of different individuals and households, it is important to define the nature of their vulnerability. An increasing
amount of theoretical and empirical work on the concept of ‘vulnerability’ has led to a range of definitions, indicators and
measurement tools, which have come to characterise this field of study. As a result, there is no one general consensus. This
paper presents the results from the latest in a series of applied studies conducted since 2004 by a network of scientists
working in southern Africa, aimed at refining the definition and application of the concept of vulnerability. The study employed
a recently developed multiple-stressor model to guide the collection and analysis of data from three sites in South Africa
and Malawi. In this paper, we identify and explore five key ‘symptoms’ of vulnerability emerging from our multi-country data
and reflect on the usefulness of the model employed. 相似文献
50.
Bunnell JE Tatu CA Bushon RN Stoeckel DM Brady AM Beck M Lerch HE McGee B Hanson BC Shi R Orem WH 《Environmental geochemistry and health》2006,28(6):577-587
In May and September, 2002, 14 private residential drinking water wells, one dewatering well at a lignite mine, eight surface
water sites, and lignite from an active coal mine were sampled in five Parishes of northwestern Louisiana, USA. Using a geographic
information system (GIS), wells were selected that were likely to draw water that had been in contact with lignite; control
wells were located in areas devoid of lignite deposits. Well water samples were analyzed for pH, conductivity, organic compounds,
and nutrient and anion concentrations. All samples were further tested for presence of fungi (cultures maintained for up to
28 days and colonies counted and identified microscopically) and for metal and trace element concentration by inductively-coupled
plasma mass spectrometry and atomic emission spectrometry. Surface water samples were tested for dissolved oxygen and presence
of pathogenic leptospiral bacteria. The Spearman correlation method was used to assess the association between the endpoints
for these field/laboratory analyses and incidence of cancer of the renal pelvis (RPC) based on data obtained from the Louisiana
Tumor Registry for the five Parishes included in the study. Significant associations were revealed between the cancer rate
and the presence in drinking water of organic compounds, the fungi Zygomycetes, the nutrients PO4 and NH3, and 13 chemical elements. Presence of human pathogenic leptospires was detected in four out of eight (50%) of the surface
water sites sampled. The present study of a stable rural population examined possible linkages between aquifers containing
chemically reactive lignite deposits, hydrologic conditions favorable to the␣leaching and transport of toxic organic compounds
from the lignite into the groundwater, possible microbial contamination, and RPC risk. 相似文献