Arsenic Contamination of Groundwater: A Review of Sources, Prevalence, Health Risks, and Strategies for Mitigation

Abstract

Arsenic contamination of groundwater in different parts of the world is an outcome of natural and/or anthropogenic sources, leading to adverse effects on human health and ecosystem. Millions of people from different countries are heavily dependent on groundwater containing elevated level of As for drinking purposes. As contamination of groundwater, poses a serious risk to human health. Excessive and prolonged exposure of inorganic As with drinking water is causing arsenicosis, a deteriorating and disabling disease characterized by skin lesions and pigmentation of the skin, patches on palm of the hands and soles of the feet. Arsenic poisoning culminates into potentially fatal diseases like skin and internal cancers. This paper reviews sources, speciation, and mobility of As and global overview of groundwater As contamination. The paper also critically reviews the As led human health risks, its uptake, metabolism, and toxicity mechanisms. The paper provides an overview of the state-of-the-art knowledge on the alternative As free drinking water and various technologies (oxidation, coagulation flocculation, adsorption, and microbial) for mitigation of the problem of As contamination of groundwater.

Advances made in Understanding the Effects of Arsenic Exposure on Humans

“…Since arsenic cannot be totally removed from the environment, solution to this problem is by two means -first, with appropriate multi-directional nontechnological based prevention strategies and management programmes, and second, with the use of advanced technology-based mitigation initiatives 69 . Prevention strategies and management programmes like finding an alternative arsenic free water source, use of deep tube wells, well switching, rainwater harvesting, social awareness, educational programmes for children and adults, community-based educational programmes, proper information on irrigation and agriculture, strategies for reducing the cost burden, proper dietary supplements and constant monitoring of health and water quality, will control and minimize the impact of arsenic toxicity [69][70][71] . Furthermore, use of advanced technologybased mitigation initiatives like arsenic sensing using arsenic detection kits and use of modern water filtration units can effectively reduce the amount of arsenic in drinking water and minimize the exposure.…”

“…Furthermore, use of advanced technologybased mitigation initiatives like arsenic sensing using arsenic detection kits and use of modern water filtration units can effectively reduce the amount of arsenic in drinking water and minimize the exposure. Removal of arsenic from water sources by biological and chemical procedures of oxidation, by coagulation-flocculation and by adsorption is also practised 69,71 . It is removed from human body using chelating agents 71 .…”

Adsorption of Arsenic from Aqueous Solutions by Iron Filings and the Effect of Magnetic Field

“…Arsenic pollution in water sources is an outcome of natural and anthropogenic sources [3] . Excessive and prolonged human intake of inorganic arsenic, through drinking water and food, causes arsenicosis, which includes skin disorders, skin cancer, internal organ cancer (bladder, kidney, liver, and lung), arm and leg vascular diseases and diabetes [4] . Arsenate closely resembles the phosphate ion and creates disorder in human energy metabolism while arsenite can link with reactive sulfur atoms present in many human enzymes and cause serious problems [5] .…”

“…Regarding the world standard changes of arsenic in drinking water from 50 to 10µg/l, many of the sources of drinking water supply in Asia are among the waters that are contaminated with arsenic [7] . Several reports on the existence of increased levels of arsenic in groundwater have been made in different countries [4] . Arsenic removal depends highly on the composition and chemistry of the polluted water [8] .…”

Contamination of Drinking Water by Arsenic in South-East Asia: Causes, Effects and Remediation

“…Thereafter, it has become a major public health problem throughout South-East Asia, particularly more severe at the high-dense population areas around the greater Dhaka, Chittagong and Khulna regions of Bangladesh, and therefore, is a great burden on water supply authorities. In developing countries like India and Bangladesh, the high prevalence of contamination, the isolation and poverty of the rural population, and the high cost and complexity of arsenic removal systems have imposed a programmatic and policy challenge on an unprecedented scale [8,9].…”