Chronic arsenic poisoning in drinking water in Inner Mongolia and its associated health effects.

Since 1990, a large number of people have been experiencing various health problems from drinking arsenic contaminated water (50-1860 microg/L) in 13 counties of Inner Mongolia, China, most of which are located in the Hetao Plain area. It is calculated that 411,243 people are currently at risk from arsenic poisoning. Clinical and epidemiological investigations were carried out on 13,021 people to ascertain the nature and degree of morbidity that occurred due to chronic arsenic toxicity.