Arsenic may be linked to type 2 diabetes

A new study of government data is the first to link low-level level arsenic exposure to type 2 diabetes, most likely from drinking water.

The results of 788 adults’ medical tests showed a nearly fourfold increase in the threat of diabetes in people with low arsenic concentrations in their urine when compared with people showing even lower levels.

Past research outside the U.S. has shown large levels of arsenic in drinking water to increase the risk for diabetes. The link at low levels is what’s new.

The Journal of the American Medical Association has printed the findings in the August 20, 2008 issue.

Lead author Dr. Ana Navas-Acien of Johns Hopkins Bloomberg School of Public Health in Baltimore said “The good news is, this is preventable.” “Since we already have a safety standard for arsenic levels in drinking water and we know drinking water is the main source of exposure, it’s important to reduce arsenic levels in drinking water where it exists,” said Navas-Acien.

New and safer drinking water standards  may be needed if new findings are similar in future studies. A new study of 4,000 people has begun.

It is known that arsenic can get into drinking water naturally when minerals dissolve. It is also an industrial pollutant from copper smelting and coal burning. Utilities use filtration systems to filter it out of drinking water.

Non-toxic organic arsenic is also found in seafood. Analysis was adjusted by the researchers for signs of seafood intake and it was found that people with type 2 diabetes had 26 percent higher inorganic arsenic levels than people without type 2 diabetes.

It is unkown how arsenic, once used as a powerful rat poison, could contribute to diabetes, but past studies have shown abnormal secretion in pancreas cells that were treated with an arsenic compound.

According to Molly Kile, an environmental health research scientist at the Harvard School of Public Health, arsenic in urine reveals exposures from all areas - air, food and water, so it is hard to trace the exact source of arsenic exposure and use these findings to establish drinking water standards.

She said it is unknown whether diabetes changes the way people metabolize arsenic. People with diabetes may even excrete more arsenic.

In 2001, the U.S. lowered arsenic standards for public water systems to 10 parts per billion because of known cancer risks. Compliance was required by 2006, after the results were collected in 2003 and 2004.

More research is necessary because of the study’s limitations. Public water systems are already in the process of meeting stricter U.S. arsenic standards.