March 27, 1996 10:30 am
The drinking water in Zimapán has an average arsenic concentration of 0.3 mg/L. The WHO drinking water standard is 0.05 mg/L. The residents of Zimapán are beginning to show ill health effects of chronic arsenic poisoning which include skin cancer and kidney and liver disease. Montgomery and Tichenor are trying to determine the source of the arsenic and the pathway by which it enters the groundwater supply.