Another reason to clear the air

A British study found a connection between pollution and stroke death, as Reuters news service:

Of 3,320 men and women who lived in a specific south London region and had a first stroke between 1995 and 2005, Dr. Ravi Maheswaran, at the University of Sheffield, and colleagues found more deaths among those exposed to higher estimated traffic-related pollution over more than a decade.

Maheswaran's team used 2002 estimates of two common traffic pollutants -- nitrogen dioxide and small, inhalable particles called particulate matter -- linked to breathing difficulties and other health problems.

Their report, in the journal Stroke, shows risk of dying increased 28 percent when nitrogen dioxide levels rose by just 10 micrograms per 3 square meters of air. A likewise increase in particulate matter increased death risk by 52 percent, they report.