From 94 to 220 million people, 85 to 90 percent of whom live in South Asia are at risk of getting arsenic in the body due to the water companies: they use deep groundwater for drinking water and crop irrigation. Scientists have made a map of the world distribution of arsenic in groundwater and assess the risk of consumption by people, the results of a study published in the journal Science.
Arsenic is an extremely toxic chemical element, the ingress of which into the human body can lead to diseases of skin, cardiovascular and nervous systems and contribute to the development of cancer. The world health organization has set the recommended concentration of arsenic in drinking water at no more than 10 milligrams per liter. The main threat is the use of groundwater: arsenic accumulates in aquifers, where reductive conditions favor the release of iron-bearing minerals.
In many arid regions of the world underground rock strata is the main source of fresh water for drinking and irrigation of crops, and the local population at risk of arsenic poisoning through rice and drinking water. Global risk assessment of arsenic poisoning of groundwater has still not been conducted due to difficulties with obtaining data on the use of water resources and agriculture in developing countries, as well as careful environmental monitoring of the chemical composition of groundwater in such regions.
Scientists led by Joel Podgorski (Joel Podgorski) and Michael Berg (Michael Berg) from the Swiss Federal Institute of aquatic science and technology created the first world map of the distribution of arsenic in groundwater (from a depth below 100 metres from surface). For its development they have compiled data from nearly 80 studies of arsenic in aquifers, which included 200 thousand analyses of water and about 55 thousand points of testing in the territories of Burkina Faso, Argentina, Mexico, China, South and South-East Asia, USA and the red river Delta in Vietnam, and sedimentary basins around the world.