BMJ.com (nee the British Medical Journal) published a study today showing that a bike share program in Barcelona, Spain saves human lives while reducing greenhouse gas emissions. The benefits from increased physical activity far outweight the risks from increased exposure to traffic and air pollutants.
Researchers in Barcelona compared the risks and benefits of bicycle travel using Barcelona’s Bicing bike share with travel by car in an urban environment. 11% of Barcelona’s residents subscribe to Bicing, with regular users biking an average of 3.29 kilometers in 14 minutes each work day.
The study finds the mortality rate for bike share users increases by 0.03 from crashes and 0.13 from increased exposure to air pollution. The increased physical activity, however, results in 12.46 fewer deaths in this population study.
Bicing has been highly successful in terms of number of subscribers and led to a large increase in trips on bicycles. A previous study showed bike promotion programs generally led to an average 3% increase in the prevalence of cycling in the population. Bicing so far has increased the number of cycling trips by 30%. Eleven per cent of the population in Barcelona subscribes to Bicing, although only 1.7% of the population are regular users.
The researchers conclude that low cost public bicycle sharing systems aimed at encouraging commuters to cycle are worth implementing in other cities, not only for the public health benefits but also for potential co-benefits such as a reduction in air pollution and greenhouse gases. Spain and the United States have roughly equivalent traffic fatality rates, so these conclusions may also apply to American cities.
BMJ is a peer reviewed medical journal published by the British Medical Assocation and advocates evidence based medicine. Because BMJ is an open access journal, the complete text of the study is available online. Which rocks.