Traces of Arsenic in Drinking Water May Increase Risk of Diabetes

Author: Drucilla Dyess

It has recently been discovered that drinking water contaminated with arsenic may be associated with the development of type 2 diabetes. Arsenic is a natural metal element of the earth's crust that has been used in committing the "perfect murder" for centuries because it is tasteless, colorless, and odorless. Over time, scientists have proven that long-term consumption of drinking water tainted with arsenic causes cancers of the bladder, lung, kidney, and skin, in addition to other diseases and conditions. Type 2 diabetes is a disease that now accounts for 10 percent of all American dollars spent on healthcare. Trace amounts of arsenic that occur naturally in drinking water supplies may be contributing to the disease with those drinking the contaminated water being totally unaware of the dangers.

Researchers from Johns Hopkins University have found that Americans with the highest inorganic arsenic levels in their urine are more than three times more likely to develop diabetes than those people with the lowest arsenic levels. This discovery coincides with previous research in animals that has shown increases in blood glucose and insulin levels from chronic exposure to arsenic and is consistent with studies from Taiwan, Bangladesh, and Mexico that have connected high arsenic levels with diabetes.

Data was studied from the 2003-2004 National Health and Nutrition Examination Survey, in which 788 adults had their urine tested for arsenic exposure. Those participants with type 2 diabetes had a 26 percent higher level of total arsenic in their urine than those without the disease. Organic arsenic that is non-toxic and often found in seafood, was found to be at similar levels in both groups.

The researchers adjusted for diabetes risk factors and seafood intake and found that participants in the top 20 percent of total urine arsenic had 3.6 times the odds of having type 2 diabetes as those with total urine arsenic in the lowest 20 percent. Researchers then looked at levels of a compound created when inorganic arsenic is metabolized before excretion. Participants with the highest levels had 1.6 times the risk of having type 2 diabetes as those with the lowest levels.

According to Ana Navas-Acien, a physician and epidemiologist at Johns Hopkins University and the lead author of the study, although the law requires utility companies to keep arsenic levels in drinking water below 10 parts per billion, 15 percent of Americans who get their drinking water from private wells are offer much less protection allowing people to have high levels of arsenic in their water and without knowing it. Navas-Acien explained, "People who get their drinking water from private wells and live in areas where groundwater is naturally contaminated with arsenic are at an especially high risk of being exposed to water with levels above the 10 parts per billion acceptable limit set by the Environmental Protection Agency."

There is a simple and affordable lab test that can determine if a well has been contaminated with arsenic. The test costs from $20 to $35 and if contamination is found, water filters and other water quality improvement systems can resolve the problem. This is a small price to pay considering the alternative possibilities.

Some reasons that inorganic arsenic may contribute to diabetes include arsenic's contribution to oxygen-related cell damage, inflammation, and cell death. All of these issues are linked to diabetes. In addition, insulin-sensitive cells exposed to insulin plus sodium arsenic seem to take in less glucose than cells exposed to insulin only. Arsenic may also influence genetic factors that interfere with insulin sensitivity as well as other processes. However, additional research needs to be conducted to determine the level of association between arsenic and diabetes.