The health risks and benefits of cycling in urban environments compared with car use: health impact assessment study

Abstract

Objective To estimate the risks and benefits to health of travel by bicycle, using a bicycle sharing scheme, compared with travel by car in an urban environment.

Air pollution as a risk factor in health impact assessments of a travel mode shift towards cycling

“…In one study, Johansson et al [37], individual data on people’s home and work addresses were used, as well as their age, sex, and expected physical capacity, in order to establish realistic bicycle travel distances. Rojas-Rueda et al [38] and Woodcock et al [39] evaluated the current benefit of increased cycling due to a public bicycle-sharing program. Dhondt et al [40] simulated the travel activity patterns before and after an increase in fuel prices, while Macmillan et al [41] simulated the effects of policy changes employing the System Dynamics Modelling.…”

“…All except two studies – Holm et al [42] and Xia et al [46] – measured physical activity as a continuous variable and employed published risk estimates to evaluate the health impacts of increased cycling. The HEAT tool was applied in seven studies to assess impact of physical activity on all-cause mortality [36,38,43,44,47,48,50]. Holm et al [42] and Xia et al [46] used categories of physical activity and the corresponding relative risks (RRs).…”

“…Nine studies examined the air pollution impact on the general population [34–37,40,41,46,48,50], four estimated impacts on active commuters [38,39,42,43], and five included impacts on both the general population and active commuters [22,44,45,47,49]. The included studies modeled both particulate and gaseous pollutants such as particulate matter (PM) less than 2.5 µm and less than 10 µm (PM2.5 and PM10), sulfur dioxide, nitrogen dioxide (NO 2) and nitrogen oxides (NOx), carbon monoxide, ammonia, etc.…”

“…Johansson et al [37] used NOx, NO 2 and black carbon (BC) as exhaust indicators and compared the size of the estimated health impacts. Some studies also employed air pollutants in their sensitivity analysis that were different from the pollutants in their main analysis [38,44]. …”

“…Some studies also performed sensitivity analyses to tackle uncertainties associated with the use of published RRs. Dhondt et al [40], Grabow et al [50], and Rojas-Rueda et al [38,44] used Monte Carlo simulations to check the variation in RRs, whereas Holm et al [42] used the upper and lower limits of the confidence interval to obtain bounds for the disease burden. Johansson et al [37] compared the differences in impacts using different exposure indicators.…”