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Inorganic arsenic is a potent human carcinogen and toxicant which people are exposed to mainly via drinking water and food. The objective of the present study was to assess current exposure to arsenic via drinking water in three European countries. For this purpose, 520 individuals from four Hungarian, two Slovakian and two Romanian countries were investigated by measuring inorganic arsenic and methylated arsenic metabolites in urine by high performance liquid chromatography with hydride generation and inductively coupled plasma mass spectrometry. Arsenic in drinking water was determined by atomic absorption spectrometry. Significantly higher concentrations of arsenic were found in both the water and the urine samples from the Hungarian counties (median: 11 and 15 microg dm(-3), respectively; p < 0.001) than from the Slovakian (median: 0.94 and 4.5 microg dm(-3), respectively) and Romanian (median: 0.70 and 2.1 microg dm(-3), respectively) counties. A significant correlation was seen between arsenic in water and arsenic in urine (R(2)= 0.46). At low water arsenic concentrations, the relative amount of dimethylarsinic acid (DMA) in urine was increased, indicating exposure via food. Also, high body mass index was associated with higher concentrations of arsenic in urine (p= 0.03), mostly in the form of DMA. Smokers had significantly higher urinary arsenic concentrations than non-smokers (p= 0.03). In conclusion, elevated arsenic exposure via drinking water was prevalent in some of the counties. Exposure to arsenic from food, mainly as DMA, and cigarette smoke, mainly as inorganic arsenic, are major determinants of arsenic exposure at very low concentrations of arsenic in drinking water.  相似文献   
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Contamination of natural aquatic ecosystems by hospital wastewater is a major environmental and human health issue. Disinfectants, pharmaceuticals, radionuclides and solvents are widely used in hospitals for medical purposes and research. After application, some of these substances combine with hospital effluents and, in industrialised countries, reach the municipal sewer network. In certain developing countries, hospitals usually discharge their wastewater into septic tanks equipped with diffusion wells. The discharge of chemical compounds from hospital activities into the natural environment can lead to the pollution of water resources and risks for human health. The aim of this article is to present: (i) the steps of a procedure intended to evaluate risks to human health linked to hospital effluents discharged into a septic tank equipped with a diffusion well; and (ii) the results of its application on the effluents of a hospital in Port-au-Prince. The procedure is based on a scenario that describes the discharge of hospital effluents, via septic tanks, into a karstic formation where water resources are used for human consumption. COD, Chloroform, dichlomethane, dibromochloromethane, dichlorobromomethane and bromoform contents were measured. Furthermore, the presence of heavy metals (chrome, nickel and lead) and faecal coliforms were studied. Maximum concentrations were 700 NPP/100 ml for faecal coliforms and 112 mg/L for COD. A risk of infection of 10? 5 infection per year was calculated. Major chemical risks, particularly for children, relating to Pb(II), Cr(III), Cr(VI) and Ni(II) contained in the ground water were also characterised. Certain aspects of the scenario studied require improvement, especially those relating to the characterisation of drugs in groundwater and the detection of other microbiological indicators such as protozoa, enterococcus and viruses.  相似文献   
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Land capability classification systems define and communicate biophysical limitations on land use, including climate, soils and topography. They can therefore provide an accessible format for both scientists and decision-makers to share knowledge on climate change impacts and adaptation. Underlying such classifications are complex interactions that require dynamic spatial analysis, particularly between soil and climate. These relationships are investigated using a case study on drought risk for agriculture in Scotland, which is currently considered less significant than wetness-related issues. The impact of drought risk is assessed using an established empirical system for land capability linking indicator crops with water availability. This procedure is facilitated by spatial interpolation of climate and soil profile data to provide soil moisture deficits and plant available water on a regular 1-km grid. To evaluate potential impacts of future climate change, land capability classes are estimated using both large-scale ensemble (multi-simulation) data from the HadRM3 regional climate model and local-scale weather generator data (UKCP09) derived from multiple climate models. Results for the case study suggest that drought risk is likely to have a much more significant influence on land use in the future. This could potentially act to restrict the range of crops grown and hence reduce land capability in some areas unless strategic-level adaptation measures are developed that also integrate land use systems and water resources with the wider environment.  相似文献   
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Women have the right to support that enables them to breastfeed. Supporting breastfeeding in emergencies is important because artificial feeding places mothers and children at risk. In emergencies, artificial feeding is dangerous to the infant, difficult and requires substantial resources. In contrast, breastfeeding guards infant health. It is also protective against postpartum haemorrhage, maternal depletion, maternal anaemia and closely spaced births and should therefore concern not only nutritionists, but also those involved in reproductive health. However, it is common for women's ability to breastfeed to be undermined in emergencies by the indiscriminate distribution of breast-milk substitutes and the absence of breastfeeding support. Controlling the distribution of breast-milk substitutes, providing supportive environments, and appropriate medical and practical assistance to breastfeeding women safeguards the health and well-being of mothers and babies. Greater collaboration between the nutrition and reproductive health sectors is required to promote best practice in protecting breastfeeding women and their children in emergencies.  相似文献   
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Herbarium plants were used as a material to study possible long-term changes in mineral elements of forest plants. Plants from South Norway collected in the period 1870 to 1930 were compared to plants collected in 1982. Relative to mineral contents in plants from 1870 to 1930, the 1982 material showed elevated levels of Zn, Cd, Rb, K, Mn and Ti and decreased levels of Sr, B, Ca and Mo in some of the plant species analysed. Most of these differences may be explained by changes in the environmental conditions, due to differences in chemical composition of precipitation, accelerated soil acidification and subsequent increasing mineral weathering. Consequently analysis of herbarium plants seems to provide valuable information about preindustrial levels of mineral elements and seems to detect changes in mineral elements brought about by recent anthropogenic activity.  相似文献   
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Recreational horseback riding is an important, but less studied, component of human interaction with the natural environment and often occurs alongside other outdoor recreational activities. Using choice experiment data collected from a survey conducted in Kentucky, this study assesses rider preferences and economic values associated with various equestrian trail attributes for daylong horseback riding trips in rural trail systems. Results indicate that while individuals have different opinions, trail attributes such as length of trail, scenic views, and travel distance from home all have significant economic implications. In addition, riders prefer trails that are restricted for horse riding only. Willingness to pay estimates of all attributes increase substantially when the travel cost to reach the trail is also considered. Policy implications on maintaining current and creating new trails in a multi-user setting are given, such as the opportunities for separating horseback riders from other users while still providing other beneficial attributes like options for longer trails and scenic views to all groups.  相似文献   
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