Aerosol cans used to use CFCs, but this propellant has been banned in many places due to its impact on the ozone layer.
The term “ozone depletion” actually refers to two separate events: the steady depletion of ozone in the stratosphere at a rate of 3% per year, and the seasonal depletion of the ozone layer in the polar region. This layer protects the Earth from the effects of ultraviolet light (UVB); a steady decline in ozone means more of these rays reach the planet’s surface, increasing the risk of skin cancer and affecting everything from plankton populations to agricultural production.
Atmospheric chlorine derived from chlorofluorocarbons (CFCs) converts ozone into oxygen molecules.
The main culprits in the destruction of the ozone layer are chlorofluorocarbon compounds (CFCs), also known as freons, and bromofluorocarbon compounds, also known as halons. CFCs are mainly used as refrigerants. Until 1995, they were the base compound used in aerosol sprays, air conditioners, and as cleaning agents for electronic equipment. Since then, the Montreal Protocol has banned their use in commercial products and urged manufacturers to replace CFCs with less harmful chemicals, such as hydrochlorofluorocarbons (HCFCs), which affect the ozone 90% less than CFCs.
Until 1995, aerosols used chlorofluorocarbon compounds, which deplete the ozone layer.
Some of the more common products that contain ozone-depleting chemicals include aerosol inhalers for asthma sufferers and fire extinguishers. Although the active production of CFCs is already banned in the United States, many countries around the world still manufacture them or sell products that contain them, such as solvents, aerosol sprays, and blowing agents used in factories. CFCs in car air conditioners were once a big problem, but a new system in cars now recycles CFCs instead of releasing them into the atmosphere. However, this is only true for newer models, and cars in developing countries and models made before 1993 still have the old system. The same goes for CFCs present in refrigerators and air conditioning units in homes and buildings.
HCFCs, although less harmful, still cause problems. They are being phased out of production, but official sources estimate that a complete ban will not occur until 2030. If all use of CFCs and HCFCs is stopped, the ozone layer could eventually repair itself.