In January 2018 researchers from the UK and USA published the results of their study to assess the respiratory and cardiovascular effects of walking down a busy street with high levels of pollution or walking in a traffic-free area with lower pollution levels. A total of 119 individuals, aged 60 and over, were involved in the study, of whom 40 were healthy, 40 had chronic obstructive pulmonary disease, and 39 ischaemic heart disease. Each individual was assessed and then undertook a 2 hour walk along a commercial street in London (Oxford Street) or in an urban park (Hyde Park). On a separate occasion the individuals undertook the other walk. During each walk, black carbon, levels of particulate matter, ultrafine particles, and nitrogen dioxide levels were measured, all of which were higher along Oxford Street than in Hyde Park. Results showed that those with chronic obstructive pulmonary disease experienced more cough, sputum, shortness of breath and wheeze after walking down Oxford Street compared with walking in Hyde Park. In all individuals, irrespective of their disease status, walking in Hyde Park led to an increase in lung function. However, this beneficial effect was lost after walking along Oxford Street.
Sinharay R et al. Respiratory and cardiovascular responses to walking down a traffic-polluted road compared with walking in a traffic-free area in participants aged 60 years and older with chronic lung or heart disease and age-matched healthy controls: a randomised, crossover study. Lancet. 2018 Jan 27;391(10118):339-349