Arsenic in groundwater of south Asia:The worst hydrogeological problem in the world!

Arsenic in groundwater of south Asia:
The worst hydrogeological problem in the world!

Arsenic (As) is a chemical element occurring naturally in rocks and soils (4). It is introduced into the environment through dissolution from minerals and ore bodies, through erosion of local rocks close to groundwater extraction points, and through the combustion of fossil fuels (1). Mining can intensify As levels in groundwater due to oven roasting of As-bearing ores (e.g. arsenopyrite – FeAsS) (3). As can also be introduced into the environment through industrial effluent and atmospheric deposition (2). Organic arsenic is nowhere near as toxic as inorganic As is to humans and As cannot be seen, tasted or smelled when it is dissolved in water (1,4). According to the World Health Organisation (WHO) Guidelines for drinking water quality, 0.01mg/L is the provisional guideline value of As in drinking water (1). In Bangladesh and other parts of Asia this guideline is raised to 0.05mg/L due to...