交通部運輸研究所Institute of Transportation, MOTC

　　Outdoor air pollution contributes to mortality and morbidity. In this dissertation, we estimated the impact of outdoor and traffic-related air pollution on public health in Taiwan. Attributable cases of morbidity and mortality and potential gain in life expectancy were estimated.

　　Epidemiology-based concentration-response functions for a 10 μg/m3 increase in inhalable coarse particulate matter, i.e. PM10, and fine particulate matter, i.e. PM2.5, were used to quantify the effects of air pollution. For PM10, cases attributable to air pollution were estimated for mortality (adults ?30 years), respiratory hospital admissions and cardiovascular hospital admissions (all ages). The traffic-related fraction was estimated based on Taiwan emission data system (TEDS) for PM10 emission inventories. For PM2.5, cases attributable to air pollution were estimated for all-cause mortality (adults ?30 years), cardiopulmonary mortality (adults ?30 years), and lung cancer (adults ?30 years). We quantified the public health impact of long-term exposure to PM2.5 in terms of attributable number of deaths and the potential gain in life expectancy by reducing PM2.5 annual levels to 25 μg/m3, 20 μg/m3, 15 μg/m3, and 10 μg/m3.

　　The results indicate that air pollution caused 18% of total mortality or more than 22,000 attributable cases for PM10 in 2007. More than half of all mortality caused by air pollution could be attributed to motor vehicle traffic, accounting also for 13,000 cases of mortality. 180,000 additional cases of chronic bronchitis, and 210,000 asthma attacks were found to be attributable to motor vehicle emissions. For PM2.5, when the guideline for PM2.5 long-term exposure was set at 25 μg/m3, we could prevent 2.6% of all-causes mortality or 3,600 deaths in 2010. The potential gain in life expectancy at age 30 of this reduction would increase by a range between one month and seven months.

　　These health impact assessments estimate the public health impacts of recent patterns of air pollution. Although individual health risks of air pollution are relatively small, the public health consequences are considerable. Several limitations could affect health impact assessment estimates as sources of uncertainty and variability. However, even after taking the overall uncertainty of these assessments into account, we emphasize the need to consider outdoor air pollution and traffic-related air pollution as a widespread cause of impaired health. In a century moving toward sustainable development and health, closer collaboration of public health and environmental policies will improve the well-being. Our results show that air quality guidelines for PM10 should be tightened both in short-term and long-term. For PM2.5, especially for long-term exposure, should be adopted in Taiwan as soon as possible to protect public health.