adverseeffects aerosols air airpollutants analysis atmosphere atmospheric atmosphericozone cancer climaticchanges congresses environmentalaspects fluorocarbonsindustry globalwarming governmentpolicy greenhouseeffect kk8083 organohalogencompounds ozone ozone-depletingsubstances ozonelayer ozonelayerdepletion pollution scienceandstate skin stratosphere tropics unitedstates wa754a84571979