Mortality, Greenhouse Gas Emissions, and Consumer Cost Impacts of Replacing Short Car Trips with Cycling: A Health Impact Assessment Study

Abstract

Background Physical inactivity is important risk factors for poor health. Replacing short car trips with active travel, such as cycling, provides practical way to incorporate physical activity for everyday life. Such change would also help to reduce fuel costs and transport related greenhouse gas (GHG) emissions. In this study we quantified changes in mortality, GHG emissions, and consumer costs for number of travel scenarios. Methods We used National Travel Survey to estimate number and distance of the short car trips in England. All trips less than 1, 2, 3, 5 and 8 miles long were progressively replaced with cycling by taking into account speed of the average cyclist. For each replaced trip, age, gender and SES of the traveller was recorded. The SES was measured by using the National Statistics Socio-Economic Classification (NS-SEC) system, which is an occupation based classification of SES widely used in the UK. The health benefits were illustrated by estimating changes in physical activity related all-cause mortality. Consumer cost savings were estimated based on average fuel prize and GHG emissions based on the average emission of the private car. All calculations were performed on the working age population (20 to 69 year old) of England, totaling 34.2 million adults. Results Premature mortality was reduced by between 75, 811, 2284, 4904 and 7648 cases per year for 1, 2, 3, 5 and 8 miles scenarios, respectively. Mortality reductions were greatest amongst people of medium and high SES. Similarly transport fuel costs savings fell more for people of high SES. Net GHG emissions decreased by between 0.2 and 10.6 Million tons of carbon dioxide equivalent (MtCO2e) per year for the 1 mile and 8 mile scenarios, respectively, representing 0.5% and 19% reduction in national transport related GHG emissions. Conclusions Replacing short car trips with cycling offers the potential for net benefits for health, GHG emissions and consumer costs. These results give quantitative information on potential health, GHG emission and consumer cost changes that replacing short car trips could achieve in population level.