Research just published indicates that New South Wales has one third of the people smoking in cars compared to New Zealand.
Of nearly 5000 cars observed in Sydney, only 1% had smokers, compared to 2.9% of 10,000 cars in New Zealand. Since 2009, vehicles have legally been required to be smokefree in New South Wales when there is a child under 16 as a passenger, but there is no similar law in New Zealand.
University of Otago, Wellington researcher, Associate Professor Nick Wilson, says that the much lower level of cars with people smoking in Sydney is likely to be a result of the New South Wales law.
He says smoking in cars creates extremely high levels of pollution, even higher than in smoky pubs, and impacts on the health of children and non-smokers.
"This is further evidence why New Zealand politicians need to protect children with a law against smoking in cars. We have laws for seat belts and mobile phone use by drivers, and protecting children's health is also very important."
He added that "while New Zealand used to be an international leader in controlling the tobacco epidemic, it is now falling behind Australia in a number of areas such as smoking in cars and plain packaging of tobacco packs."
"Second-hand smoke in a car is 23 times more toxic than in a house, due to the enclosed space," says Dr Tristram Ingham, Medical Adviser for the Asthma Foundation. "Smoke-exposed children have more respiratory and ear infections, chronic bronchitis, wheezing, and asthma. They also have more frequent medical visits, are hospitalised more frequently, and miss more schooldays."
The research involved developing an app for smartphones to allow observers to count cars with people smoking. The app is available free from the TobaccoFree website, and app users who register on the website can download new observations on smoking in cars from anywhere in the world. Currently, both Android and iPhone (iOS) versions are supported.
Another University of Otago researcher, Dr Mariusz Nowostawski, says that both the smartphone application and website source code are freely available. This means they can be used as the basis for further refinements to the existing app, or the code can be used as a basis for other usages. Those uses could include counting observed mobile phone use in cars to help improve the effectiveness of the law on mobile phone use.
This study has been published in the international journal Journal of Epidemiology and Community Health.
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Download the app for free from the NZDIS TobaccoFree website.