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Atmospheric implications

The rates of the tropospheric reactions of the alkenes and, in particular, haloalkenes with OH, NO3, Cl, etc. are important compared with those of other saturated volatile organic compounds. For the haloalkenes, reactivity decreases with increasing substitution by halogen atoms in the molecule. Of all the chloroethenes, only C2Cl4 has an atmospheric lifetime which allows its presence in the upper troposphere where photolysis might take place, thus contributing to stratospheric ozone depletion through catalytic cycles.
In general, rapid removal of haloalkenes in the troposphere through reaction with OH and other radicals could lead to a decrease in tropospheric radical concentrations, thus having an indirect impact on stratospheric ozone through enhanced catalytic destruction.