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431.
A dynamic model for assessing the transfer of tritium in a food chain was applied to the Loire River, where 14 nuclear power plants situated on five different sites operate. The model considers several potential exposure pathways in the aquatic and terrestrial ecosystems: transfer of tritium through the aquatic food chain (especially fish); use of river water for agricultural purposes (irrigation) and transfer of radionuclides through the terrestrial food chain (vegetables, meat, milk); subsequent internal exposure of humans due to ingestion of contaminated foodstuffs. For biological environmental compartments, the transfer of tritium to organic matter (i.e. OBT) was simulated. For each of the parameters introduced in this model, a probability density function, allowing further uncertainty and sensitivity analyses, was proposed. Uncertainty/sensitivity analyses were performed to determine a confidence interval for the mean annual dose to critical groups and to identify the parameters responsible for the uncertainty and subsequent research priorities.  相似文献   
432.
New best estimates for the solid–liquid distribution coefficient (Kd) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The Kd best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil–radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide Kd are examined to complete the information derived from the best estimates with a rough prediction of Kd based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of Kd best estimates for a number of radionuclides, such as selenium, antimony, and iodine.  相似文献   
433.
Among all emerging substances in water, pharmaceutical products (PPs) and residues are a lot of concern. These last two years, the number of studies has increased drastically, however much less for water resources and drinking water than for wastewater. This literature review based on recent works, deals with water resources (surface or groundwater), focusing on characteristics, occurrence and fate of numerous PPs studied, and drinking water including water quality. Through this review, it appears that the pharmaceutical risk must be considered even in drinking water where concentrations are very low. Moreover, there is a lack of research for by-products (metabolites and transformation products) characterization, occurrence and fate in all water types and especially in drinking water.  相似文献   
434.
Human exposure to ambient ozone (O3) has been linked to a variety of adverse health effects. The ozone level at a location is contributed by local production, regional transport, and background ozone. This study combines detailed emission inventory, air quality modeling, and census data to investigate the source–receptor relationships between nitrogen oxides (NOx) emissions and population exposure to ambient O3 in 48 states over the continental United States. By removing NOx emissions from each state one at a time, we calculate the change in O3 exposures by examining the difference between the base and the sensitivity simulations. Based on the 49 simulations, we construct state-level and census region-level source–receptor matrices describing the relationships among these states/regions. We find that, for 43 receptor states, cumulative NOx emissions from upwind states contribute more to O3 exposures than the state's own emissions. In-state emissions are responsible for less than 15% of O3 exposures in 90% of U.S. states. A state's NOx emissions can influence 2 to 40 downwind states by at least a 0.1 ppbv change in population-averaged O3 exposure. The results suggest that the U.S. generally needs a regional strategy to effectively reduce O3 exposures. But the current regional emission control program in the U.S. is a cap-and-trade program that assumes the marginal damage of every ton of NOx is equal. In this study, the average O3 exposures caused by one ton of NOx emissions ranges from ? 2.0 to 2.3 ppm-people-hours depending on the state. The actual damage caused by one ton of NOx emissions varies considerably over space.  相似文献   
435.
436.
Environmental Science and Pollution Research - Activated carbon prepared from grape branches was used as a remarkable adsorbent to uptake naproxen and treat a synthetic mixture from aqueous...  相似文献   
437.
Environmental Science and Pollution Research - Few studies have documented the air quality, noise, thermal comfort, and health risk assessment of household kitchens related to Sub-Sahara Africa. In...  相似文献   
438.
Sea ice continues to decline across many regions of the Arctic, with remaining ice becoming increasingly younger and more dynamic. These changes alter the habitats of microbial life that live within the sea ice, which support healthy functioning of the marine ecosystem and provision of resources for human-consumption, in addition to influencing biogeochemical cycles (e.g. air–sea CO2 exchange). With the susceptibility of sea ice ecosystems to climate change, there is a pressing need to fill knowledge gaps surrounding sea ice habitats and their microbial communities. Of fundamental importance to this goal is the development of new methodologies that permit effective study of them. Based on outcomes from the DiatomARCTIC project, this paper integrates existing knowledge with case studies to provide insight on how to best document sea ice microbial communities, which contributes to the sustainable use and protection of Arctic marine and coastal ecosystems in a time of environmental change.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01658-z.  相似文献   
439.
Illegal wildlife crime is a global phenomenon, accelerating the ongoing biodiversity crisis. In the Old World, and particularly in Africa, illegal use of poisons to eliminate carnivores is the main driver of the continental vulture crisis. Knowledge about the underlying source and drivers of this threat is lacking for most areas, including Kenya, a global vulture and biodiversity hotspot. An extensive questionnaire survey of over 1300 respondents was run, using a specialized questioning technique and quantitative analytical approaches. Results show that, while pastoralists have a positive attitude towards vultures, over 20% of them use poisons to eliminate predators. Poisoning was largely driven by livestock losses to predators, and by negative attitude towards predators. Poisoning was less prevalent among respondents aware of the Kenya Wildlife Act. Overall, we suggest that a combination of top-down, e.g. legislation, and bottom-up (such as corrals or compensation) along with awareness campaigns may help reduce poisoning on the ground.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01695-8.  相似文献   
440.
Felton  Adam  Löfroth  Therese  Angelstam  Per  Gustafsson  Lena  Hjältén  Joakim  Felton  Annika M.  Simonsson  Per  Dahlberg  Anders  Lindbladh  Matts  Svensson  Johan  Nilsson  Urban  Lodin  Isak  Hedwall  P. O.  Sténs  Anna  Lämås  Tomas  Brunet  Jörg  Kalén  Christer  Kriström  Bengt  Gemmel  Pelle  Ranius  Thomas 《Ambio》2020,49(5):1065-1066
Ambio - In the original published article, the sentence “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and...  相似文献   
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