China has the most air pollution fatalities with 1.4 million deaths a year followed by India with 645,000 and Pakistan with 110,000. Worldwide, agriculture is the No. 2 cause of deaths by polluting air. The problem with farms is ammonia from fertilizer and animal waste. The big air pollution killers are the soot particles resulted from combining the ammonia with sulfates from coal-fired power plants and nitrates from car exhaust. Traffic and power plants would be the biggest cause of deadly soot and smog. The United States had 54,905 deaths linked to polluted air in 2010.