A new study has been completed by researchers at the Harvard School of Public Health showing that levels of secondhand smoke particles in cars can reach dangerous levels, even when windows are open. Based on 45 trials, they report that peak levels with closed windows were over 500 μg m-3, on average, and peak levels with open windows were about 100 μg m-3, on average. See if you can simulate levels of this magnitude using the vehicle simulation model available on this website.
An article describing the study is appearing in the November 2006 issue of the American Journal of Preventive Medicine and can be downloaded.
Vaughan Rees, the lead author on the paper, says that “The smoke particle levels we measured are alarming and are above the threshold for what’s considered unhealthy for sensitive groups — people like children and the elderly."