This study investigates the association between long-term exposure to traffic-related air pollution and the risk of coronary heart disease (CHD) hospitalization and mortality. The research included 452,735 residents of Metropolitan Vancouver aged 45-85 years, who were followed for 4 years after a 5-year exposure period. Traffic-related air pollutants, including black carbon, fine particles (PM2.5), nitrogen dioxide (NO2), and nitric oxide (NO), were estimated using land-use regression models. The results showed that an interquartile range increase in black carbon concentration was associated with a 3% increase in CHD hospitalization and a 6% increase in CHD mortality. There was a clear linear exposure-response relationship between black carbon and coronary events. The study concludes that long-term exposure to traffic-related fine particulate air pollution, indicated by black carbon, may explain the observed associations between exposure to road traffic and adverse cardiovascular outcomes.This study investigates the association between long-term exposure to traffic-related air pollution and the risk of coronary heart disease (CHD) hospitalization and mortality. The research included 452,735 residents of Metropolitan Vancouver aged 45-85 years, who were followed for 4 years after a 5-year exposure period. Traffic-related air pollutants, including black carbon, fine particles (PM2.5), nitrogen dioxide (NO2), and nitric oxide (NO), were estimated using land-use regression models. The results showed that an interquartile range increase in black carbon concentration was associated with a 3% increase in CHD hospitalization and a 6% increase in CHD mortality. There was a clear linear exposure-response relationship between black carbon and coronary events. The study concludes that long-term exposure to traffic-related fine particulate air pollution, indicated by black carbon, may explain the observed associations between exposure to road traffic and adverse cardiovascular outcomes.