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101.
Environmental Science and Pollution Research - Free ferulic acid (FA) is a natural compound with antioxidant properties which mitigates the negative effects of cold stress in sheep; however, its...  相似文献   
102.
To add data on trace metal contamination of Humboldt penguins in the South Pacific, levels of trace metals (As, Hg, Pb, Cu, Zn, and Cd) and porphyrins (copro-, uro-, and proto-) in excreta of Humboldt penguins that inhabit some important nesting sites on the northern coast of Chile were determined. Fresh excreta were collected on Pan de Azúcar Island, Chañaral Island, and Cachagua Island, from December 2011 to January 2012. Concentration of metals was determined by flame atomic absorption spectrophotometry, whereas porphyrins levels were measured by fluorimetric analysis. Concentrations (dry weight) of Cu (199.67 μg g?1), As (7.85 μg g?1), and Pb (12.78 μg g?1) were higher (p?≤?0.05) in Cachagua Island. Colonies from Pan de Azúcar Island showed the highest levels of Hg (0.76 μg g?1), Cd (47.70 μg g?1), and Zn (487.10 μg g?1). Samples from Cachagua Island showed the highest (p?≤?0.05) levels of copro- (2.16 nmol g?1), uro- (2.20 nmol g?1), and protoporphyrins (2.23 nmol g?1). There was a positive correlation between the metals As, Pb, and Cu with uro-, copro-, and protoporphyrins. The results indicated that penguin colonies from Cachagua Island are more exposed to metal contamination than penguin colonies from Pan de Azúcar and Chañaral Islands, thus being more likely to develop certain diseases caused by contamination with metals. Considering biomagnification, the metals detected in the excreta of Humboldt penguins can be a source of contamination from marine environments to terrestrial ecosystems, which could also affect other living organisms.  相似文献   
103.
Proper assessment of soil cadmium (Cd) concentrations is essential to establish legislative limits. The present study aimed to assess background Cd concentrations in soils from the state of São Paulo, Brazil, and to correlate such concentrations with several soil attributes. The topsoil samples (n?=?191) were assessed for total Cd contents and for other metals using the USEPA 3051A method. The background concentration was determined according to the third quartile (75th). Principal component analysis, Spearman correlation, and multiple regressions between Cd contents and other soil attributes (pH, cation exchange capacity (CEC), clay content, sum of bases, organic matter, and total Fe, Al, Zn, and Pb levels) were performed. The mean Cd concentration of all 191 samples was 0.4 mg kg?1, and the background concentration was 0.5 mg kg?1. After the samples were grouped by parent material (rock origin) and soil type, the background Cd content varied, i.e., soils from igneous, metamorphic, and sedimentary rocks harbored 1.5, 0.4, and 0.2 mg kg?1 of Cd, respectively. The background Cd content in Oxisols (0.8 mg kg?1) was higher than in Ultisols (0.3 mg kg?1). Multiple regression demonstrated that Fe was primarily attributed to the natural Cd contents in the soils (R 2?=?0.79). Instead of a single Cd background concentration value representing all São Paulo soils, we propose that the concentrations should be specific for at least Oxisols and Ultisols, which are the primary soil types.  相似文献   
104.

Purpose  

Solid waste incineration has recently attracted much attention because the combustion process involved produces highly toxic organohalogen contaminants such as dioxin-like polychlorinated biphenyls (DL-PCBs) present in fly ash. This has raised the need for simple, rapid, accurate methods for monitoring PCBs in ash samples.  相似文献   
105.
106.

Purpose  

This paper analyses the presence of polychlorinated biphenyls (PCBs) in escaped: farmed and wild salmons in southern Chile, analysing their concentrations and congener profiles in two species (Oncorhynchus kisutch and Oncorhynchus mykiss).  相似文献   
107.
108.
Since 1995, the Institute for Environment and Development in Portugal has obtained >300 stack samples from various point sources of Portuguese industries. A coherent database was made with the collected results. The limit values fixed by several European legal documents consulted, Portuguese, Spanish, French, Italian, and Dutch emission legislation, were applied to the Institute for Environment and Development stack sampling inventory (from 1995 to 2000) to evaluate the efficiency of these standards in promoting the control and reduction of atmospheric pollutants emissions, especially regarding nitrogen oxides, sulfur dioxide, and particulate matter. The conclusion was that the original Portuguese legislation was not restrictive enough and not very efficient regarding emissions reduction. In contrast, the Dutch and Italian legislations are quite restrictive but very efficient concerning emission control for the three pollutants analyzed. One of the outcomes of this study was the publication of a new law in Portugal regulating the emissions of atmospheric pollutants. The strategy of this emissions control law follows the conclusions found in this study including the concept of a mass flow threshold and different approaches depending on source dimension.  相似文献   
109.
The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies.  相似文献   
110.
This article presents an analysis of the application of a cleaner production program within a Brazilian printing company and describes its specific characteristics to propose a benchmark for similar efforts at other companies. As a result, a very number of improvement opportunities (136) were identified, indicating that the printing industry needs to make reasonable, collective efforts to ensure that companies' environmental systems reach international marks.  相似文献   
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