Previous research has shown that air pollution boosts the chances of acute cardiovascular events such as stroke and heart attack, but it hasn’t been known whether it also increases the likelihood of chronic diseases such as diabetes and high blood pressure.
In this study, researchers examined the link between these chronic illnesses and exposure to nitrogen oxides and particulate matter, also known as particle pollution. Nitrogen oxides are indicators of traffic-related air pollution.
The study included about 4,000 black women living in Los Angeles who were followed from 1995 to 2005. During that time, 531 new cases of hypertension and 183 new cases of diabetes were diagnosed in the women, said study leader Patricia Coogan, an associate professor of epidemiology at the Boston University School of Public Health and the Slone Epidemiology Center at Boston University, and colleagues.
For each increase of 12 parts per billion (ppb) in exposure to nitrogen oxides, there was a 24 percent rise in the risk of diabetes and an 11 percent rise in the risk of hypertension. Exposure to particle pollution also appeared to increase the risk for having both diseases, but the evidence for this was weaker than for nitrogen oxides.