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681.
Polychlorinated biphenyls (PCBs) are among the most toxic environmental pollutants. Food, especially animal based, has been described as the major source for human exposure to PCBs. We investigated PCB levels (congeners 10, 28, 52, 153, 138, and 180) in cheese from 14 cities of Rio Grande do Sul, Brazil. The fat was extracted using sodium sulfate and petroleum ether, and PCBs purification was conducted using florisil and hexane. The identification and quantification were made in a gas chromatograph with microelectron capture detector (GC-microECD). PCB congeners were found (lower bound data as ngg(-1) fat) in the following rank: 52 (15.75)>180 (4.91)>28 (3.43)>153 (3.00)>10 (2.38)>138 (1.37). Summation operatorPCB contamination ranged from 0 to 78.32 ngg(-1) fat. Differences in PCB levels between industrialized (33.32 ngg(-1) fat) and homemade (26.58 ngg(-1) fat) cheese and between two different regions (36.19 vs. 26.95 ngg(-1) fat) were not statistically significant. For university students, the estimated daily intake (EDI) of PCBs from cheese ranged from 0 to 3.13 pgkg(-1) b.w. EDI was significantly higher for industrialized than homemade cheese, and for cheese from Mountain/Porto Alegre region than from Santa Maria/South/Western region. No sample exceeded maximum level of PCBs allowed in dairy products in the European Community.  相似文献   
682.
Journal of Material Cycles and Waste Management - Waste foundry sand (WFS) is a waste generated during the molding of metal parts and primarily discarded in landfills, which generates environmental...  相似文献   
683.
Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the...  相似文献   
684.
Environmental Science and Pollution Research - A real industrial effluent from the pre-treatment and painting processes was polished through adsorption using alternative biochar derived from grape...  相似文献   
685.
Journal of Material Cycles and Waste Management - Anaerobic digestion of the organic fraction of municipal solid wastes is a well-established process for biogas production and various forms of...  相似文献   
686.
Environmental Science and Pollution Research - The growth in global production and consumption rates has resulted in increased pollution generation by industrial companies. To this end, cleaner...  相似文献   
687.
Journal of Material Cycles and Waste Management - Waste water contaminated with inorganic mercury is considered a serious environmental problem, mainly due to the hazardous effects this contaminant...  相似文献   
688.
Journal of Material Cycles and Waste Management - Cement waste (CW) is one of the main environmental problems in the cement industry due to the high amount that is used and its incorrect disposal....  相似文献   
689.

When performed without technical criteria, the rapid expansion of irrigated agricultural frontiers can result in overexploitation of water, causing worrying impacts on the balance of agroecosystems. This study proposes a model applied to the state of Bahia, to estimate the water demand of areas irrigated by a central pivot, in order to contribute to information that will subsidize the inspection and planning of water resources in the promotion of sustainable agriculture. The irrigated areas were identified and measured by photointerpretation using orbital images from the Landsat-8 satellite. With a historical series of data, the reference evapotranspiration was calculated and monthly water balance was elaborated. The data obtained were spatialized by kriging, and with punctual values of water deficit (mm), the water demand of the irrigated perimeter of the equipment was estimated. The results were described considering strategic planning units, proposed from municipalities, hydrographic basins and biomes. A total of 4075 pivots were quantified, covering an irrigated area of 265,896.30 ha and with an average annual consumption of 1,333,473,208.02 m3 of water. Areas of high demand were identified, especially in the western region of Bahia, which includes the hydrographic basin of the São Francisco River and the Cerrado biome, concentrating 80.85% and 75.47% of the state water demand for pivots, respectively. Considering possible points of water vulnerability and continuity of this expansion, the results provide the primary information needed to encourage the adoption of public policies aimed at the management of water resources. The study method proposes guidelines that condition the application in any region of interest in the world.

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690.
Environmental Science and Pollution Research - There are increasing worldwide concerns about the negative impacts of healthcare waste generated in hospitals, especially in low- and middle-income...  相似文献   
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