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Smoking in cars harms kids even when windows are open

Smoking in cars produces harmful pollution exceeding World Health Organisation “safe” levels - even if windows are down and the air conditioning is on.

Such exposure is “likely” to affect the health of children in the car, claimed the study, published in Tobacco Control.

Researchers endorsed the recent report from the Royal College of Physicians Tobacco Advisory Group, calling for a ban on smoking in cars, in a bid to reduce the overall prevalence of smoking and the harms associated with exposure to second hand smoke.

Several other countries, including Canada, the US, Australia, Cyprus and South Africa have already introduced state or national legislation to ban smoking in cars in which children are passengers.

Researchers measured the levels of fine particulate matter every minute in the rear passenger area during typical car journeys made by 17 smokers and non-smokers over a three day period.

The drivers - 14 of whom were smokers, made a total of 104 journeys, lasting from 5 to 70 minutes, with an average duration of 27 minutes.

Particulate matter levels were available for 83 journeys, of which 34 were smoke free. They averaged 7.4 µg/m3 during non-smoking journeys, but were around 10 times as high (85 µg/m3) during smoking journeys.

Even though smokers opened car windows to provide some ventilation, levels of particulate matter still exceeded the maximum safe limit recommended by the World Health Organisation of 25 µg/m3, at some point during all car journeys during which somebody smoked.

Exposure to second hand smoke is linked to several children's health problems, including sudden infant death, middle ear disease, wheeze and asthma.

“Children are likely to be at greater risk from [second hand smoke] exposure due to their faster breathing rates, less developed immune system and their inability to move away from the source in many home and car settings,” said the researchers.