The two biggest air pollution culprits are transportation sources such as cars and trucks and stationary sources such as oil refineries and industrial facilities. The ALA rankings look at two different pollutants: ozone (smog) and fine particulate matter. Take the first step and take your vehicle to the STAR stations to be carried out necessary checks.
Ground-level ozone is formed when nitrogen oxides and volatile organic compounds "cook" in sunlight to produce ozone. This mix of chemicals largely stems from the burning of fossil fuels: the pollution that comes from o…