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71.
The levels of cadmium and lead in 36 raw bovine milk samples were analysed. These samples come from seven farms with a semi-extensive grazing system and were collected between the autumn of 2007 and the winter of 2008. All the farms were located in Asturias (Spain), a zone of great industrial and mining activity in the proximities of the Caudal River. The samples were collected in sterile precleaned polypropylene tubes and frozen until the analysis. After a lyophilization process, the samples were treated with nitric acid and microwave treatment. Cadmium and lead determinations were carried out using inductively coupled plasma mass spectrometry with sensibility under 0.2 ppb for liquid matrix. The lead content was found to vary from 0.71 to 16.06 μg/kg wet weight (w.w.), and the cadmium was lower than 2 μg/kg w.w. The levels of lead in milk are higher in those farms near zones of storage of mining waste depots, thermal power and areas with high levels of traffic. All the values found are in concordance with research carried out at non-polluted areas, and those for the lead are well below the European Union limitations.  相似文献   
72.
This paper evaluates the feasibility of establishing a multiple-use marine protected area. The methodology was applied to evaluate three proposed sites in Chile with diverse conservation needs, social stress and poverty levels, and different economic activities (small-scale fishing, heavy industry, and mining activities). We use two broad categories for the evaluation: socio-economic and political–institutional. The methodology uses a combination of secondary data with personal interviews, workshops, and focus groups with stakeholders (e.g., fishermen, unions, politicians, social organizations) from different political, social, and economic backgrounds to characterize current and potential natural and social resources and to evaluate in an ordinal scale the feasibility of establishing the protected area. The methodology allows us to correctly identify the challenges faced in each site and can be used to develop appropriate strategies for balancing economic, social, and environmental objectives. This methodology can be replicated to evaluate the feasibility of other marine or terrestrial protected areas.  相似文献   
73.
Rodríguez L  Macías F 《Chemosphere》2006,63(9):1598-1609
We calculated the sensitivity of Galician forest soils to eutrophication caused by atmospheric deposition of nitrogen compounds, using the Simple Mass Balance (SMB) method as described by [Posch, M., de Vries, W., Hettelingh, J.-P., 1995. Critical loads of sulphur and nitrogen. In: Posch, M., de Smet, P.A.M., Hettelingh, J.-P., Downing, R.J. Calculation and Mapping of Critical Thresholds in Europe. Status Report 1995, Coordination Center for Effects, National Institute for Public Health and the Environment, Bilthoven, The Netherlands, pp. 31-42]. Deposition values were used to calculate critical loads exceedance. Galician natural forest ecosystems can support nitrogen deposition loads of more than 10 kg Nha (-1) yr (-1). The lowest critical loads (approximately 10 kg Nha (-1) yr (-1)) mainly occurred in forest stands in the interior zone, while highest critical load values (approximately 68 kg Nha (-1) yr (-1)) were observed in eucalyptus stands at low altitudes in the littoral area. Exceedances based on N deposition levels, calculated from data recorded in 2001, occurred in 40% of the forest soils, showing the need to control N emissions in these areas to prevent possible eutrophication of soils and waters. Analysis of rainfall bulk composition revealed that ammonium, probably derived from agricultural and cattle activities, was the main compound responsible for N deposition in Galicia.  相似文献   
74.
Ketoprofen is an analgesic with potent anti-inflammatory activity against acute inflammation, subacute inflammation, for the acute and long-term treatment of various inflammatory pathologies, as rheumatoid arthritis and colonic adenocarcinoma. In order to minimize the incidence of systemic events related to ketoprofen, the transdermal drug delivery system development has been most important. The advantages of using natural rubber latex membranes include not only the reduction of adverse systemic events, but also the suitability of the low cost of the material together with its physicochemical properties such as flexibility, mechanical stability, surface porosity and water vapor permeability, and besides being a biocompatible material also presents biological activity to stimulate the angiogenesis, being able to be used in tissue repair. This study demonstrated that ketoprofen was successfully incorporated into natural latex membranes for drug delivery. FTIR indicated that the drug did not interact chemically with the membrane. Moreover, the natural latex membranes released 60% of the ketoprofen incorporated in 50 h. SEM images indicated that a portion of the drug was present on the membrane surface, being this portion responsible for the burst release. The tensile tests showed that the addition of the drug into the natural latex membrane did not influence on the polymer mechanical behavior. In addition, drug-natural latex membranes presented no red blood cell damaging effects. Our data shows that the ketoprofen loaded natural latex membranes is a promising system for sustained drug delivery which can be used to minimize the adverse side effects of high dose systemic drug delivery.  相似文献   
75.
The geochemical characteristics of coal cleaning rejects (CCR) in Santa Catarina State, Brazil, were investigated. Around 3.5 million ton/ year of coal waste are dumped in Santa Catarina State. Coal beneficiation by froth flotation results in large amounts of CCR composed of coaly and mineral matter, the latter characterised by the occurrence of sulphide minerals and a broad array of leachable elements. The total and leachable contents of more than 60 elements were analysed. Atmospheric exposure promotes sulphide oxidation that releases substantial sulphate loads as well as Ca2?+?, K?+?, Mg2?+?, Cl??? and Al3?+?. The metals with the most severe discharges were Zn, Cu, Mn, Co, Ni and Cd. Most trace pollutants in the CCR displayed a marked pH-dependent solubility, being immobile in near-neutral samples. The results highlight the complex interactions among mineral matter solubility, pH and the leaching of potentially hazardous elements.  相似文献   
76.
Plastics are dominant pollutants in freshwater ecosystems worldwide. Scientific studies that investigated the interaction between plastics and freshwater biodiversity are incipient, especially if compared to the marine realm. In this review, we provide a brief overview of plastic pollution in freshwater ecosystems around the world. We found evidence of plastic ingestion by 206 freshwater species, from invertebrates to mammals, in natural or semi-natural ecosystems. In addition, we reported other consequences of synthetic polymers in freshwater ecosystems—including, for instance, the entanglement of animals of different groups (e.g., birds). The problem of plastic pollution is complex and will need coordinated actions, such as recycling programs, correct disposal, stringent legislation, regular inspection, replacement of synthetic polymers with other materials, and ecological restoration. Current information indicates that the situation in freshwater ecosystems may be as detrimental as the pollution found in the ocean, although highly underappreciated.Supplementary InformationThe online version of this article (10.1007/s13280-020-01496-5) contains supplementary material, which is available to authorized users.  相似文献   
77.
Environmental Science and Pollution Research - This work investigated an innovative alternative to improve municipal wastewater treatment plant effluent (MWWTP effluent) quality aiming at the...  相似文献   
78.
Environmental Science and Pollution Research - Chitosan induces tolerance to abiotic stress agents in plants. However, studies on the different application forms of this biopolymer are limited....  相似文献   
79.
Environmental Science and Pollution Research - High soil copper (Cu) concentrations in vineyards can cause phytotoxicity to grapevine rootstocks. In order to mitigate toxicity, the use of grapevine...  相似文献   
80.
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