|
THURSDAY, Oct. 19 (HealthDay News) -- Rolling the windows down
while driving doesn't eliminate the unhealthy effects of
secondhand smoke for kids and other sensitive passengers, a new
U.S. study finds.
"The levels were above the threshold for what's considered
unhealthy for sensitive groups -- people like children and the
elderly -- as determined by the Environmental Protection Agency
(EPA)," study author Vaughan Rees, a research associate at
the Harvard School of Public Health, said in a prepared statement.
For this study, researchers attached a pollution monitor to a
child safety seat in a car and had a smoker-volunteer drive an
hourlong route. This was repeated 45 times. On some drives, all
the car windows were down. On other journeys, the driver's side
window was opened only about two inches, and the other windows
were closed.
The pollution monitor measured levels of "PM 2.5"--
particulate matter or particle pollution in the air that was 2.5
micrometers in diameter or smaller. The smaller the particles, the
easier it is for them to get into the lungs.
According to the EPA's Air Quality Index, 24 hours of exposure
to PM 2.5 levels greater than 40 micrograms per cubic meter is a
health risk for sensitive people, including children, the elderly,
and those with certain medical conditions. Levels of PM 2.5
greater than 250 micrograms are a health hazard for all people.
When all the car windows were wide open, the average level of
PM 2.5 in the car was 51 micrograms, compared to 272 micrograms
when only the driver's window was opened slightly, the study said.
"At 40 miles an hour, on an open road, there's quite a lot
of air movement inside the vehicle, but that wasn't sufficient to
completely remove the secondhand smoke. In other words, the smoke
really hangs around," Rees said.
The study is published in the November issue of the American
Journal of Preventive Medicine.
Some U.S. states have banned smoking in private vehicles to
protect children from secondhand smoke.
More information
The American Lung Association has more about secondhand
smoke and your family.
|