Why you should walk to work through quieter routes

London: Commuting to work by walking on quieter side streets rather than main roads can help people avoid exposure to harmful air pollution, says a new study.

Lee Koh from London's Queen Mary University used a hand-held monitor to measure levels of black carbon particulate matter while walking between Whitechapel in the east of London to Moorgate, between 4.00 p.m. to 7.00 p.m. using main roads.

She then used an urban walking route planner to plan a quieter route that might potentially have lower levels of air pollution.Short-term exposure to black carbon is associated with increased hospital admissions due to respiratory symptoms,

and that long-term exposure is associated with exacerbations and increased prevalence of asthma. Black carbon is one of the components of air pollution, and comes from incomplete combustion by diesel vehicles.