Every week cities around the world bemoan their traffic problems and look for ways to solve them. Reports abound on the knock-on effects that traffic chaos has on our stress levels and the health and wealth of our economies. The typical debate surrounding investment in public transport vs new roads tends to focus largely on dollars, but some new research gives us perhaps the best reason to consider leaving the car at home: public health.
Earlier this month, the results of a major European study published in The Lancet has found that even low levels of pollution caused by traffic fumes can cause cancer. The presence of microscopic particles (“particulate matter” or PM as it is known) in the air we breathe has been shown to significantly increase the incidence of lung cancer, specifically, adenocarcinoma (the only form of lung cancer commonly found among non-smokers).
The study was purposefully broad – combining data from seventeen existing studies in nine European countries, including more than 300,000 people who had died of lung cancer, tracked over 13 years. The research team sourced environmental data retrospectively from the locales of the cancer victims to identify the potential risk. The result: there is no safe level of particulate matter in our air, despite the quality standards set for us by our authorities. At every level tested, the presence of particulate matter increased the risk of lung cancer.
The concentration of these particles in our air varies from day to day and even hour to hour (NSW residents can check here, for example), and the average exposure over time is reported. The study found that a 5 mcg/m3 increase of of PM 2.5 (these are particles 30 times smaller in diameter than a human hair) resulted in an 18% increase in cancer risk, while an 10mcg/m3 increase in concentration of of PM10 (a slightly larger particle, still microscopic), led to a 22% higher risk factor.
Ole Raaschou-Nielsen from the Danish Cancer Society Research Centre in Copenhagen summed up the results: ”We found no threshold below which there was no risk,” ‘The more the worse, the less the better.”
Air pollution is everybody’s problem, and like it or not, driving a car is a significant contributor to pollution. There are no easy solutions, but in light of studies such as this, it is essential that both the short-term and the long-term costs are considered in in the decision-making process.