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991.
Health Risk Assessment of Heavy Metals in Soils and Vegetables from a Typical Greenhouse Vegetable Production System in China 总被引:2,自引:0,他引:2
There is growing concern about food safety and environmental contamination due to potential health risks to consumers. The aims of this study are to elucidate the accumulation status, influencing factors, and potential risk of selected heavy metals in soils and vegetables from a typical greenhouse vegetable production system in China. The potential health risks of heavy metals through soil contact and vegetable consumption were evaluated for greenhouse and corresponding open field production. The results indicated that the mean concentrations of Hg, Pb, Cu, and Zn in greenhouse vegetable soils were greater than those in open field soils. Leaf vegetables had relatively higher concentrations and transfer factors of heavy metals than root and fruit vegetables, especially for Cd. The target hazard quotient of heavy metals through vegetable consumption was greater than 1 for leaf vegetables, and was also higher for greenhouse vegetables than those from open field. The risk of exposure to heavy metals through direct contact with soil and vegetable consumption was higher for children than for adults and seniors. Planting patterns with different vegetable types and soil properties can affect bioavailability and crop accumulation of heavy metals. 相似文献
992.
The concentrations of 10 metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Se, Zn) were determined in drinking water in Khingan, China, a forest zone after long-term excessive deforestation. These metals’ concentrations in water exceeded background values of metals in some other regions of the world, indicating that there were other metal sources contributing to such high levels of metals in Khingan. Arsenic was the only metal whose concentration exceeded the maximum levels allowed in drinking water. Principal component analysis showed that As, Cd, Cu, and Se originated from anthropogenic sources and exhibited significantly high concentrations in north Khingan, while Fe and Mn derived from natural formation and showed significantly high concentrations in central Khingan. Health risks from metals were evaluated by a model recommended by the U.S. Environmental Protection Agency. Ingestion was the predominant pathway of exposure to metals in water for local residents. Arsenic was also the only metal causing both noncarcinogenic hazard and carcinogenic risk in Khingan. The high risks occurred mainly in north Khingan and are associated with coal combustion. This study indicates that long-term excessive deforestation may increase As concentration considerably in drinking water and then pose health risks to local residents. 相似文献
993.
The aim of the study is to assess the probabilistic non-cancer and cancer risks by recreational bathing in Tres Arroyos creeks (southeastern Buenos Aires Province, Argentina). In these waters, hazardous substances (heavy metals, pesticides) have been detected, possibly related to agricultural activities. To assess such risk, USEPA models in aggregated (exposure through accidental oral water intake and dermal contact simultaneously) and cumulative approaches (combined exposure to more than one substance) were applied, performed for bathers of 5, 10, 15, and 20 years old. The results show that chronic bathing in these waters is not harmful at the concentrations and the exposure scenarios considered. Arsenic was the riskiest substance for both non-cancer and cancer effects, affecting mainly the youngest age group, and the accidental water intake during bathing was the most relevant pathway of exposure. On the other hand, the study highlights the key role of the frequency and duration of the bath event. We discuss the results in light of a previous paper of our authorship concluding that the health risk assessment is a valid alternative to analyze recreational water quality, which, unfortunately, is unused by water management agencies in Argentina. 相似文献
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Military areas are valuable habitats and refuges for rare and endangered plants and animals. We developed a new approach applying innovative methods of hyperspectral remote sensing to bridge the existing gap between remote sensing technology and the demands of the nature conservation community. Remote sensing has already proven to be a valuable monitoring instrument. However, the approaches lack the consideration of the demands of applied nature conservation which includes the legal demands of the EU Habitat Directive. Following the idea of the Vital Signs Monitoring in the USA, we identified a subset of the highest priority monitoring indicators for our study area. We analyzed continuous spectral response curves and tested the measurability of N = 19 indicators on the basis of complexity levels aggregated from extensive vegetation assemblages. The spectral differentiability for the floristic as well as faunistic indicators revealed values up to 100% accuracy. We point out difficulties when it comes to distinguishing faunistic habitat requirements of several species adapted to dry open landscapes, which in this case results in Overall accuracy of 67, 87–95, and 35% in the error matrix. In summary, we provide an applicable and feasible method to facilitating monitoring military areas by hyperspectral remote sensing in the following. 相似文献
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Matthew R. Hunt Lisa Schwartz Christina Sinding Laurie Elit 《Developing world bioethics》2014,14(1):47-55
In this article, we present an ethics framework for health practice in humanitarian and development work: the ethics of engaged presence. The ethics of engaged presence framework aims to articulate in a systematic fashion approaches and orientations that support the engagement of expatriate health care professionals in ways that align with diverse obligations and responsibilities, and promote respectful and effective action and relationships. Drawn from a range of sources, the framework provides a vocabulary and narrative structure for examining the moral dimensions of providing development or humanitarian health assistance to individuals and communities, and working with and alongside local and international actors. The elements also help minimize or avoid certain miscalculations and harms. Emphasis is placed on the shared humanity of those who provide and those who receive assistance, acknowledgement of limits and risks related to the contributions of expatriate health care professionals, and the importance of providing skillful and relevant assistance. These elements articulate a moral posture for expatriate health care professionals that contributes to orienting the practice of clinicians in ways that reflect respect, humility, and solidarity. Health care professionals whose understanding and actions are consistent with the ethics of engaged presence will be oriented toward introspection and reflective practice and toward developing, sustaining and promoting collaborative partnerships. 相似文献
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目的 分析政府补偿与监管机制改革对公立医疗卫生机构教学、科研以及学科建设的影响。方法 通过对上海市闵行区的机构调查,收集并分析2008—2012年3所公立综合性医院和12家社区卫生服务中心的医学教育、科研项目、论文发表及重点学科建设状况的相关数据。结果 闵行区公立综合性医院和社区卫生服务中心的医学教育和科研能力有所提升,重点学科建设也有所加强;但仍然存在教学能力薄弱,科研水平层次偏低,缺乏高质量的重点学科等问题。结论 政府补偿与监管机制改革在一定程度上强化了公立医疗机构的医学教育、科研能力和学科建设,但未来需进一步加大对科教和学科建设的鼓励和支持力度。 相似文献