Arsenic in drinking water:sources,occurrence and health effects(a review)

摘要

Because dramatic cases of arsenic contamination of water resources,soils,vegetables,humans and animals increase,this review has focussed on the fate and behaviour of this element and what kind of health impacts are related with its release in surface or ground waters.In a first part,we point out how the primary minerals can lead to As mobilization and exportation by surface waters and suspended matter.We also emphasize the particular key role for As retention through both adsorption onto natural Fe(III)(hydr)oxides,Mn oxides and/or precipitation as Fe(III)arsenates.Nowadays,numerous and efficient systems for arsenic removal from any natural resources are available to produce good quality drinking water(with <10 mu g/l As);however it is not within the scope of the present review.In a second part we focus on recent knowledge about the human toxicity of the various arsenic species.Chronic exposure to As in drinking water lead to many health diseases and,although the mechanisms of toxification/detoxification are not well identified,the role of methylated species is discussed.Some epidemiologic studies are cited,but the exact relationship between past chronic As exposure and present health diseases has been questioned.