Leaf surfaces collect tiny particles from vehicle exhaust
PORTLAND, Ore. — Foliage on trees lining traffic routes could serve as low-tech pollution sensors, a new analysis suggests.
The exhaust of many vehicles, particularly those that burn diesel, includes copious quantities of microscopic particles of many sizes. Although particles larger than 10 micrometers in diameter are efficiently filtered by the upper respiratory system, those smaller than 2.5 micrometers across can reach areas deep within the human lung to trigger disease and inflammation, says Bernard Housen, a geophysicist at Western Washington University in Bellingham.
When Housen and university colleague Luigi Jovane analyzed leaves colle