摘要：Inorganic arsenic is naturally occurring in groundwaters throughout the United States. This study investigated arsenic exposure and self-report of 9 chronic diseases. We received private well-water samples and questionnaires from 1185 people who reported drinking their water for 20 or more years. Respondents with arsenic levels of 2 μg/L or greater were statistically more likely to report a history of depression, high blood pressure, circulatory problems, and bypass surgery than were respondents with arsenic concentrations less than 2 μg/L. Inorganic arsenic is commonly found in groundwaters throughout the United States. In October 2001, the US Environmental Protection Agency reduced the maximum contaminant level drinking water standard for arsenic from 50 μg/L to 10 μg/L. By 2006, all public drinking water supplies in the United States are required to comply with the new standard. This new standard is based on existing epidemiological evidence documenting the association between arsenic exposure and cancers of the lung and bladder. The health effects associated with inorganic arsenic exposure are numerous and include basal cell cancer of the skin; tumors of the bladder, kidney, liver, and lung 1– 4 ; blood vessel damage 5 ; peripheral vascular and cardiovascular disease 4, 6– 8 ; numbness in the hands and feet 9, 10 ; and diabetes mellitus. 11, 12 Many studies have documented associations between arsenic exposure and chronic illness; however, most have focused on high exposures and cancers. 2, 4, 5, 13– 15 Less studied have been the effects of low-level arsenic exposure. In 1987, a groundwater study conducted by the Wisconsin Department of Natural Resources identified arsenic in groundwater above the maximum contaminant level coincident with a bedrock layer at the interface of the St. Peter Sandstone and Sinnippee Dolomite. The geologic formation exists beneath more than 20 000 private water supply wells throughout several Wisconsin counties. Water samples collected from 1943 private wells between 1992 and 1993 contained arsenic concentrations that ranged from less than 2 μg/L to 12 000 μg/L. Nearly 20% of the water samples contained concentrations that exceeded the new federal drinking water standard of 10μg/L. 16 The principal objective of this research was to evaluate the prevalence of 9 different chronic diseases in adults who drink water from privately owned wells in the at-risk area.
