CHEMICAL COUPLING BETWEEN ATMOSPHERIC OZONE AND PARTICULATE MATTER

A major fraction of ambient particulate matter arises from atmospheric gas-to-particle conversion. Attempts to reduce particulate matter lev els require control of the same organic and nitrogen oxide (NOx) emiss ions that are precursors to urban and regional ozone formation. Modeli ng of the gas-aerosol chemical interactions that govern levels of part iculate components showed that control of gas-phase organic and NOx pr ecursors does not lead to proportionate reductions of the gas-phase-de rived components of atmospheric particles. The chemical coupling betwe en ozone and particulate matter has implications for strategies to ach ieve the new ozone and particulate matter standards proposed by the U. S. Environmental Protection Agency.