LAUSR

The beneficial cardiopulmonary effects of walking can be impaired by traffic pollution in patients with ischaemic heart disease (IHD) or chronic obstructive pulmonary disease (COPD), and in healthy individuals. In a randomized, crossover study published in The Lancet, 135 participants (39 with IHD, 40 with COPD, and 40 healthy controls) were assigned a 2 h walk along Oxford Street (a commercial street in London, UK) or in Hyde Park (an urban park). Oxford Street had higher concentrations of black carbon, NO2, PM10, PM2.5, and ultrafine particles than Hyde Park. All participants showed a beneficial increase in lung function and a decrease in pulse wave velocity and augmentation index (measures of arterial stiffness) up to 26 h after walking in Hyde Park; these effects were attenuated after walking on Oxford Street. “Policies should aim to control ambient levels of air pollution along busy streets in view of these negative health effects,” conclude the investigators.