A national epidemiologic study has found a strong, consistent correlation between adult diabetes and particulate air pollution that persists after adjustment for other risk factors like obesity and ethnicity, according to researchers from Children’s Hospital Boston. The relationship was seen even at exposure levels below the current EPA regulations.
The report, published in the October issue of Diabetes Care, is among the first large-scale, population-based studies to link diabetes prevalence with air pollution. It is consistent with prior laboratory studies that found an increase in insulin resistance, a precursor to diabetes, in obese mice exposed to particulates, and an increase in markers of inflammation (which may contribute to insulin resistance) in both the mice and obese diabetic patients after particulate exposure.
Like the laboratory studies, the current study focused on fine particulates of 0.1-2.5 nanometers in size (known as PM2.5), a main component of haze, smoke and motor vehicle exhaust. The investigators, led by John Pearson and John Brownstein, Ph.D., of the Children’s Hospital Informatics Program, obtained county-by-county data on PM2.5 pollution from the Environmental Protection Agency (EPA), covering every county in the contiguous United States for 2004 and 2005.