NEW YORK (Reuters Health) - Exposure to low-to-moderate levels of inorganic arsenic in drinking water and food may increase the risk of type 2 diabetes, according to a study released Tuesday, which found that individuals with diabetes had higher levels of arsenic in their urine compared to individuals without diabetes.
High chronic exposure to inorganic arsenic is a documented risk factor for diabetes, but the effect of lower levels of exposure is unknown, Dr. Ana Navas-Acien, from Johns Hopkins Bloomberg School of Public Health in Baltimore, and colleagues note in the Journal of the American Medical Association for August 20.
The researchers examined urine samples taken from 788 U.S. adults 20 years or older.
They found that subjects with type 2 diabetes had 26 percent higher total arsenic levels than subjects without diabetes. The likelihood of diabetes was more than 3.5-fold higher in subjects with higher urine arsenic levels relative to those with lower arsenic levels in urine.
The primary sources of inorganic arsenic are contaminated drinking water due to naturally occurring arsenic in rocks and soils, and food, the researchers point out. In the U.S., roughly 13 million people live in areas where the concentration of inorganic arsenic in the public water supply exceeds EPA-established standards, primarily in the West, Midwest and Northeast regions. Dietary intake of inorganic arsenic in the U.S. ranges from 8.4 to 14 micrograms per day for various age groups.
"Given widespread exposure to inorganic arsenic from drinking water worldwide, elucidating the contribution of arsenic to the diabetes epidemic is a public health research priority," Navas-Acien and colleagues conclude.
Drs. Molly L. Kile and David C. Christiani, at Harvard University School of Public Health in Boston, advise in a commentary published with the study: "It is prudent to minimize arsenic exposure while its effect on metabolic diseases continues to be researched."
SOURCE: Journal of the American Medical Association, August 20, 2008.
