Indeks
Arsenic, a toxic chemical often found at low levels in U.S. public drinking water, may increase the risk of developing diabetes, researchers said.
In the first study of its kind, scientists found Americans with high levels of arsenic in their urine were almost four times more likely to have diabetes than those with trace levels. The risk was apparent at levels generally considered harmless and grew with increasing exposure, according to the study in the Journal of the American Medical Association.
The findings follow recent studies on contaminants, including hormones and antibiotics, making their way into U.S. public tap water. While previous research showed chronic exposure to high levels of arsenic could lead to diabetes, the new report is the first to show that even levels that meet U.S. regulations may be dangerous.
``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 lead researcher Ana Navas-Acien from the Johns Hopkins Bloomberg School of Public Health in Baltimore. ``This reinforces that arsenic is a potentially harmful environmental contaminant and it's important to have drinking water with low levels.''
The researchers analyzed data from the 2004 National Health and Nutrition Examination Survey, a nationwide health study that for the first time collected and tested arsenic levels in urine from nearly 800 volunteers. Participants with type 2 diabetes had a 26 percent higher level of arsenic overall.
Cancer, Heart Damage
Arsenic affects nearly all the organs in the body, causing ailments including lung, skin and kidney cancer, internal bleeding and heart damage, kidney and liver failure, and birth defects.
More research is needed to determine whether the arsenic exposure occurred first and then triggered the diabetes, said Navas-Acien, assistant professor of environmental health science at Johns Hopkins, in a telephone interview. It's also possible that diabetics were less able to filter out the poison, the researchers said.
Arsenic, once known as a potent rat poison, comes from mineral deposits in rocks and soil. Water contaminated with arsenic is often found in the West, Midwest and Northeast. As much as 8 percent of the U.S. public water supply, affecting 13 million Americans, may have levels that exceed government guidelines, according to reports from the Environmental Protection Agency and the U.S. Geological Survey. Millions more are exposed worldwide.
Previous studies showed arsenic raises blood sugar and insulin levels, while chronic exposure to the highest levels in places like Taiwan, Bangladesh and Mexico raised the risk of diabetes. About 24 million Americans and 171 million people worldwide have diabetes, mainly type 2, when insulin doesn't properly convert blood sugar into energy.
Diabetes Pandemic
``Stemming the pandemic of type 2 diabetes is a public health priority and will require a multi-faceted approach,'' wrote Molly Kile and David Christiani, from Harvard University School of Public Health, in an editorial accompanying the study. ``It is prudent to minimize arsenic exposure while its effect on metabolic diseases continues to be researched.''
Tap water is already the cheapest and safest source of drinking water and costs less than 10 cents a gallon compared with as much as $8 for bottled water, said Jennifer Sass, senior scientist in the Natural Resources Defense Council's health program. The organization recommends consumers rely on tap water, which is regulated, and use a filter to improve purity.
``We think the government should be doing more to test and to regulate contaminants,'' Sass said in a telephone interview. ``We'd like the government to do more to keep them out in the first place.''
In the first study of its kind, scientists found Americans with high levels of arsenic in their urine were almost four times more likely to have diabetes than those with trace levels. The risk was apparent at levels generally considered harmless and grew with increasing exposure, according to the study in the Journal of the American Medical Association.
The findings follow recent studies on contaminants, including hormones and antibiotics, making their way into U.S. public tap water. While previous research showed chronic exposure to high levels of arsenic could lead to diabetes, the new report is the first to show that even levels that meet U.S. regulations may be dangerous.
``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 lead researcher Ana Navas-Acien from the Johns Hopkins Bloomberg School of Public Health in Baltimore. ``This reinforces that arsenic is a potentially harmful environmental contaminant and it's important to have drinking water with low levels.''
The researchers analyzed data from the 2004 National Health and Nutrition Examination Survey, a nationwide health study that for the first time collected and tested arsenic levels in urine from nearly 800 volunteers. Participants with type 2 diabetes had a 26 percent higher level of arsenic overall.
Cancer, Heart Damage
Arsenic affects nearly all the organs in the body, causing ailments including lung, skin and kidney cancer, internal bleeding and heart damage, kidney and liver failure, and birth defects.
More research is needed to determine whether the arsenic exposure occurred first and then triggered the diabetes, said Navas-Acien, assistant professor of environmental health science at Johns Hopkins, in a telephone interview. It's also possible that diabetics were less able to filter out the poison, the researchers said.
Arsenic, once known as a potent rat poison, comes from mineral deposits in rocks and soil. Water contaminated with arsenic is often found in the West, Midwest and Northeast. As much as 8 percent of the U.S. public water supply, affecting 13 million Americans, may have levels that exceed government guidelines, according to reports from the Environmental Protection Agency and the U.S. Geological Survey. Millions more are exposed worldwide.
Previous studies showed arsenic raises blood sugar and insulin levels, while chronic exposure to the highest levels in places like Taiwan, Bangladesh and Mexico raised the risk of diabetes. About 24 million Americans and 171 million people worldwide have diabetes, mainly type 2, when insulin doesn't properly convert blood sugar into energy.
Diabetes Pandemic
``Stemming the pandemic of type 2 diabetes is a public health priority and will require a multi-faceted approach,'' wrote Molly Kile and David Christiani, from Harvard University School of Public Health, in an editorial accompanying the study. ``It is prudent to minimize arsenic exposure while its effect on metabolic diseases continues to be researched.''
Tap water is already the cheapest and safest source of drinking water and costs less than 10 cents a gallon compared with as much as $8 for bottled water, said Jennifer Sass, senior scientist in the Natural Resources Defense Council's health program. The organization recommends consumers rely on tap water, which is regulated, and use a filter to improve purity.
``We think the government should be doing more to test and to regulate contaminants,'' Sass said in a telephone interview. ``We'd like the government to do more to keep them out in the first place.''
