Pollution influences life expectancy. The BBC reports on a study done in the U.S. finds, unsurprisingly, that the more pollution, the shorter the life expectancy, and that when the air gets cleaner, life expectancy goes up: "It has taken a quarter of a century, but US researchers say their work has finally enabled them to determine to what extent city air pollution impacts on average life" (Hawkley, Humphrey, "City air pollution 'shortens life'" (http://news.bbc.co.uk/2/hi/health/7946838.stm). The researchers' study, begun in the 1980s, concluded that life expectancy rose two-and-a-half years, and 15% of the improvement is caused by air quality improvement (ibid). But there is much to still be done to improve air quality, especially for people who are in high-pollution areas every day such as around commuter trains and highways that have high diesel truck traffic and who are thus more susceptible to allergies, asthma, cancer, and cardio-vascular trouble (ibid.)
It's good to lower pollution levels, but what if there were not any pollution at all because the energy for power and even transportation came from something other than fossil fuels? For more information, please see www.campaignforgreen.org.