给水排水工程 外文翻译 外文文献 英文文献 砷在环境中的生化特性_精品.doc

外文文献：　 Arsenic in the environment: Biology and Chemistry Abstract： Arsenic (As) distribution and toxicology in the environment is a serious issue, with millions of individuals worldwide being affected by As toxicosis. Sources of As contamination are both natural and anthropogenic and the scale of contamination ranges from local to regional.There are many areas of research that are being actively pursued to address the As contamination problem. These include new methods of screening for As in the field, determining the epidemiology of As in humans, and identifying the risk of As uptake in agriculture.Remediation of As-affected water supplies is important and research includes assessing natural remediation potential as well as phytoremediation. Another area of active research is on the microbially mediated biogeochemical interactions of As in the environment. In 2005, a conference was convened to bring together scientists involved in many of the different areas of As research. In this paper, we present a synthesis of the As issues in the light of long-standing research and with regards to the new findings presented at this conference. This contribution provides a backdrop to the issues raised at the conference together with an overview of contemporary and historical issues of As contamination and health impacts.Crown Copyright . 2007 Published by Elsevier B.V. All rights reserved. 1. Introduction 1.1. Location and scale of problem Arsenic (As) has been detected in groundwater in several countries of the world, with concentration levels exceeding the WHO drinking water guideline value of 10 μg/L (WHO, 2001) as well as the national regulatory standards (e.g. 50 μg/L in India and Bangladesh, Ahmedet al., 2004; Mukherjee et al., 2006). Arsenic in groundwater is often associated with geologic sources, but in some locations anthropogenic inputs can be extremely important. Ingestion of geogenic As from groundwater sources is manifested as chronic health disorders in most of