Health benefits of traffic emissions controls in Melbourne, Australia

Long term exposure to traffic related air pollution (TRAP) is associated with respiratory and cardiovascular morbidity and mortality. In 2005 and 2013, Australia adopted Euro 4 and Euro 5 emissions standards, respectively, for all new vehicles, leading to gradual decreases in TRAP concentrations and associated ambient NO₂ levels. We estimated the health impacts of those emissions standards in Victoria, Australia and assessed the spatial distribution of benefits. We estimated annual mortality attributable to TRAP under pre-2005 conditions and calculated the years of life gained since. Population weighted annual average NO₂ exposures were estimated for each of the years 2005–2022 using a spatial linear regression (SLR) model and the share from vehicles was determined using a chemical transport model. Attributable mortality was estimated using the mortality concentration-response coefficient for NO₂ (1.023, 95 % CI: 1.008–1.037, per 10 μg/m³ annual average) as recommended by the Committee on the Medical Effects of Air Pollutants. Across the state, 2005 population weighted average NO₂ exposures were 3.8–40.0 μg/m³, and decreased by −1.4–9.7 μg/m³ over the years to 2022. Prior to 2005, the mortality burden of NO₂ from all anthropogenic sources (Mean 20.2 μg/m³) was 685 (95 % CI, 243–1084) premature deaths annually, corresponding with 10,355 [3623–16570] years of life lost (YLL), including 9234 [3230, 14,778] from traffic related NO₂. Tailpipe emissions controls have led to 11,889 [4170, 18,979] additional years of life among residents of Victoria, Australia, since 2005. But these benefits are concentrated in urban areas with no industry.