Los Angeles residents living near freeways experience a hardening of
the arteries that leads to heart disease and strokes at twice the rate
of those who live farther away, a study has found.
The paper is the
first to link automobile and truck exhaust to the progression of
atherosclerosis — or the thickening of artery walls — in humans. The
study was conducted by researchers from USC and UC Berkeley, joined by
colleagues in Spain and Switzerland, and was published this week in the
journal PloS ONE.
Researchers
used ultrasound to measure the wall thickness of the carotid artery in
1,483 people who lived within 100 meters, or 328 feet, of Los Angeles
freeways. Taking measurements every six months for three years, they
correlated their findings with levels of outdoor particulates — the
toxic dust that spews from tailpipes — at the residents’ homes.
They
found that artery wall thickness accelerated annually by 5.5
micrometers — one-twentieth the thickness of a human hair — or more
than twice the average progression in study participants.
The findings show, according to co-author Howard N. Hodis, director of the Atherosclerosis Research Unit at
USC’s Keck School of Medicine, “that environmental factors may play a
larger role in the risk for cardiovascular disease than previously
suspected.”
Read the full story at Greenspace, The Times’ environment blog.
— Margot Roosevelt
Photo: Cars hit a bottleneck as they emerge from the 710 Freeway in Alhambra. Credit: Gary Friedman / Los Angeles Times