School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
Environ Res. 2022 Jan;203:111782. doi: 10.1016/j.envres.2021.111782. Epub 2021 Jul 31.
Impact of arsenic (As) contaminated groundwater on human health, through drinking and irrigation practices, is of grave-concern worldwide. This paper present the review of various sources, processes, health effects and treatment technologies available for the removal of As from arsenic contaminated water. Groundwater with high As concentration is detrimental to human health and incidents of As contamination in groundwater had been reported from different parts of the globe. More serious known As contamination problem as well as largest population at risk are found in Bangladesh, followed by West Bengal state in India along the Indo-Gangetic plains. Large scale natural As contamination of groundwater is found in two types of environment such as strongly reducing alluvial aquifers (ex. Bangladesh, India, China and Hungary) and inland basins in arid or semi-arid areas (ex. Argentina and Mexico). The provisional guideline of 10 ppb (0.0 l mg/l) has been adopted as the drinking water standard by World Health Organization (WHO). In the aquatic environment, the release, distribution and remobilization of As depend on temperature, redox potential, speciation, and interaction between liquid solution and solid phases. As predicaments in the environment is due to its mobilization under natural geogenic conditions as well as anthropogenic activities. Arsenic mineral is not present in As contaminated alluvial aquifer but As occurs adsorbed on hydrated ferric oxide (HFO) generally coat clastic grains derived from Himalayan mountains. As is released to the groundwater mainly by bio-remediated reductive dissolution of HFO with corresponding oxidation of organic matter. The development of strongly reductive dissolution of mineral oxides (Fe and Mn) at near-neutral pH may lead to desorption and ultimately release of As into the groundwater. As release through geochemical process is more important factor in alluvial aquifers causing As contamination rather than sources of arsenic. As is a toxin that dissolves in the bloodstream, rendering the victim susceptible to disease of the skin, bones, and also cancer of liver, kidney, gall bladder and the intestines. It is necessary to adopt highly successful technology to treat As contaminated water into the acceptable limit for human consumption. Universally accepted solutions are not developed/available even after the lapse of almost forty years since slow As poisoning identification in tens of millions of people especially in Bengal delta. The issue poses scientific, technical, health and societal problems even today.
受污染地下水导致的砷（As）暴露对人类健康的影响已引起全世界的严重关注，这主要是通过饮水和灌溉等途径实现的。本文综述了各种来源、过程、健康影响以及从受污染的水中去除砷的处理技术。高浓度砷的地下水对人类健康有害，全球不同地区都有报道地下水砷污染事件。孟加拉国的砷污染问题最为严重，受影响的人口也最多，其次是印度的西孟加拉邦，沿印度恒河平原分布。大规模的地下水砷污染主要发生在两种环境中，一种是强还原冲积含水层（如孟加拉国、印度、中国和匈牙利），另一种是干旱或半干旱地区的内陆盆地（如阿根廷和墨西哥）。世界卫生组织（WHO）已将 10 ppb（0.01 mg/L）作为饮用水标准。在水生环境中，砷的释放、分布和再迁移取决于温度、氧化还原电位、形态和液相与固相之间的相互作用。环境中的砷困境是由于其在自然地球化学条件下以及人为活动下的迁移。砷矿物并不存在于受污染的冲积含水层中，但砷以吸附形式存在于水合氧化铁（HFO）上，通常覆盖源自喜马拉雅山脉的碎屑颗粒。砷主要通过生物还原作用使 HFO 溶解，相应地氧化有机物，从而释放到地下水中。在近中性 pH 值条件下，强烈的矿物氧化物（Fe 和 Mn）的还原溶解可能导致砷的解吸，并最终释放到地下水中。在冲积含水层中，通过地球化学过程释放砷是导致砷污染的一个更重要因素，而不是砷的来源。砷是一种毒素，会溶解在血液中，使受害者容易患上皮肤、骨骼疾病，也容易患上肝癌、肾癌、胆囊癌和肠癌。必须采用高度成功的技术，将受污染的水降至人类可接受的饮用水平。尽管在孟加拉三角洲地区发现数千万人砷中毒已经过去了近四十年，但仍未开发出（或获得）普遍适用的解决方案。即使在今天，这个问题仍然存在科学、技术、健康和社会等方面的问题。
