Heart Insure

Even in environments with low air pollution, long term exposure to traffic exhaust near people's homes may heighten their risk of stroke, according to a new study from Sweden. The culprit appears to be a fine particle air pollutant called black carbon.

The researchers came to this conclusion after investigating links between exposure to different types of particulate matter and rates of heart disease and stroke

They report their findings in a recent Environmental Health Perspectives study paper.

The authors write that they observed "few consistent associations" between heart disease and stroke and different types of particulate matter and their sources.

"However," they conclude that "long term residential exposure to locally emitted [black carbon] from traffic exhaust was associated with stroke incidence."

"This study," he says, "identifies local traffic exhaust as a risk factor for stroke, a common disease with great human suffering, high mortality and significant costs to society."

Black carbon is a sooty material that comes from burning fossil fuels. According to the study, it is a significant component of fine particle air pollution.

Vehicle and other engines that run on gas and diesel and power plants that run on coal and other fossil fuels emit black carbon along with other particulate matter.

Road traffic is the primary source of black carbon emissions in cities. Scientists have tied black carbon inhalation to respiratory conditions, cancer, cardiovascular disease, and birth abnormalities.