Type 2 diabetes linked to air pollution

BOSTON, Oct. 4 (UPI) -- There is a strong, consistent correlation between adult diabetes -- type 2 diabetes -- and particulate air pollution, U.S. epidemiologists suggest.

Study leaders John Pearson and John Brownstein of the Children's Hospital Boston Informatics Program analyzed county-by-county data on PM2.5 pollution -- fine particulates of 0.1-2.5 nanometers in size -- from the U.S. Environmental Protection Agency covering every county in the contiguous United States for 2004 and 2005.

The researchers examined the data along with data from the Centers for Disease Control and Prevention and the U.S. Census to track the prevalence of adult diabetes. They factored in known diabetes risk factors such as obesity, exercise, geographic latitude, ethnicity and population density.

The study, published in the journal Diabetes Care, found a strong and consistent association between diabetes prevalence and PM2.5 concentrations. For every 10 micrograms per cubic meter increase in PM2.5 exposure, there was a 1 percent increase in diabetes prevalence, the researchers learned.

"We didn't have data on individual exposure, so we can't prove causality, and we can't know exactly the mechanism of these people's diabetes," Brownstein said in a statement. "But pollution came across as a significant predictor in all our models."

The correlation was seen even at exposure levels below the current EPA safety limit, the study revealed.