Chlorofluorocarbons stratospheric accumulation

This chapter has outlined the history and conceptual understanding of the processes responsible for ozone depletion by chlorofluorocarbons in the stratosphere. In brief, the long lifetimes of chlorofluorocarbons are reflected in their observed worldwide accumulation in the atmosphere. Their role in stratospheric ozone depletion depends critically on... 

The rate of chemical transformation determines the rate of disappearance of a chemical from the environment and, in turn, its spatial distribution. Only very persistent chemicals can be distributed widely. The gasoline additive MTBE is widely dispersed in contaminated aquifers because it is fairly resistant to degradation in groundwater. The pesticide DDT can accumulate in remote regions, in organisms, and in the food chain because it is extremely persistent. And chlorofluorocarbons could only reach the stratosphere because of an extraordinary resistance to undergo reactions in the troposphere. 

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