The health costs of motor-vehicle-related air pollution.

Motor vehicles have significantly larger health costs than previously reported. Particulates are the most damaging pollutant, while ozone and other pollutants have smaller effects. Diesel vehicles cause more damage per mile than do gasoline vehicles, because of greater particulate emissions. Very fine particles appear more dangerous than larger particles, and combustion particles appear more dangerous than road dust. The possibility cannot be ruled out that ozone is linked to mortality and chronic illness, effects which are costly and would considerably raise the costs of ozone pollution. These results suggest that emphasis should be placed on the regulation of particulates. (Author/publisher).