what is cfc in styrofoam?
<answer> It is the chemicals that break down ozone in the troposphere. <context> Does polystyrene deplete the ozone layer? 1  Initially a portion of polystyrene production was aided by the use of chlorofluorocarbons (CFCs), the chemicals that break down ozone in the troposphere. 2  Though polystyrene manufacturers claim that their products are ozone-friendly or free of CFCs, this is only partially true. The use of hydrocarbons in polystyrene foam manufacture releases the hydrocarbons into the air at ground level; there, combined with nitrogen oxides in the presence of sunlight, they form tropospheric ozone -- a serious air pollutant at ground level.