Slide 28 of 30
- Total emissions for all criteria pollutants shown, except Nitrogen Oxides, have declined even though vehicle miles traveled and gross domestic product have increased. (pollutants shown include carbon monoxide, organic compounds, sulfur dioxide and particulate matter)
- Total emissions declined substantially on a per-capita basis, from about 1.2 pounds per person in 1972 to 0.68 in 1996. The decreases are attributable to the Clean Air Act regulations which began in 1970 and continued into the 1990's. Changes in the business cycle and improved manufacturing practices also have played a role in the decline.
- Lead emissions (too small to report in the graph) declined from an estimated 221 thousand short tons in 1970 to 3.9 thousand tons in 1996, largely due to the removal of lead from gasoline.
Source: Environmental Protection Agency, Office of Air and Radiation, National Air Pollutant Emission Trends Report: 1900 - 1996, EPA-454/R-97-011, (Washington, DC, December 1997), Appendix A.
Note: Particulate emissions including fugitive dust consist of particles less then 10 microns in diameter (PM-10).
