Taking the bus in crowded cities is a good way to reduce overall traffic, save money on gas, and do a good turn for the environment. Unfortunately, bus riders often are exposed to large amounts of pollution in the process.
Over 50 million Americans mow their lawns each week, which uses 800 million gallons of gas per year and produces tons of air pollutants. Garden equipment engines were completely unregulated with respect to emissions until the late 1990s and still emit high levels of carbon monoxide, volatile organic compounds, and nitrogen oxides. In fact, gas mowers and their relatives like leaf blowers and edgers produce 5% of the air pollution in this country.