Cambodians rank second in air quality satisfaction with an overall dissatisfaction rate of just 4 percent, according to a Gallup survey released to coincide with the 40th anniversary of Earth Day last week. The survey, which polled people from 153 countries and areas from 2006 to 2010, found that roughly 1.1 billion people are critical of the air quality in their communities. According to World Health Organization estimates, about 2 million premature deaths occur each year due to the effects of air pollution.