Freon consumption - Implications for atmospheric ozone

Freons are a potential source of stratospheric chlorine and may indirectly cause serious reductions in the concentration of ozone. The reduction could be as large as 3 percent by 1980, or 16 percent by 2000, if Freon consumption were to grow at 10 percent per year. Even if Freon use were terminated as early as 1990, it could leave a significant effect which might endure for several hundred years.