27 October 2006
Smoking in Cars a Health Risk for Children
New research published in the New Zealand Medical Journal today shows smoking in cars causes extremely high levels of
particulate air pollution from fine particulates. It is the first study in New Zealand investigating the effects on air
quality of smoking in vehicles.
The University of Otago researchers argue this demonstrates the potential adverse health effects of smoking in cars for
non-smoking passengers, particularly children whose lungs are still developing. The findings validate the public health
rationale for the current Health Sponsorship Council social marketing campaign that encourages smokers to protect their
children from the harms of second-hand smoke, by not smoking in their car.
The Wellington School of Medicine and Health Sciences researchers suggest the Government should consider a law banning
smoking in cars, where children are passengers. Some states in the USA already have this legislation, and it is being
considered in other jurisdictions e.g. New South Wales and Ontario.
“The levels of measured air pollution due to smoking in cars are extremely high, “says Dr Edwards from the Department of
Public Health at the School.” These results suggest that smokers should not smoke in cars to protect their non-smoking
passengers, particularly children.”
The investigators recorded the level of fine particles (PM2.5) in the air whilst a front seat passenger smoked a
cigarette. These particles have been associated with adverse health effects in studies of outdoor air pollution.
Average levels of fine particles were 199 micrograms/m3, (peak 217 μg/m3) when a cigarette was smoked with the smoker’s
window fully down, 162 micrograms/m3 (peak 181 μg/m3) with the window half down, and 2926 micrograms/m3 (peak 3645
μg/m3) with all windows closed.
“These levels of particulates are similar to those found in a typical smoky bar, and when the window was closed it is at
least twice as polluted as the most smoky pub,” says Dr Edwards.
For comparison, PM2.5 levels were recorded at a busy traffic intersection (Basin Reserve, Wellington) at 5pm, and were
only 3-5 micrograms/m3. Compared to very poor air quality days in Auckland (PM2.5 around 35-40 μg/m3), particulate
levels in the car during smoking were about five times higher with a window wholly or partially open, and up to 100
times higher with the windows closed. The World Health Organization guidelines for annual average and 24 hour average
PM2.5 levels are 10 micrograms/m3 and 25 g/m3 respectively.
This research follows another study last month that showed a quarter of cars in Wellington with someone smoking also had
other occupants. This research was based on 16,000 vehicles in the Wellington area.
ENDS