Man-made causes of depletion of ozone layer: The main cause for the depletion of ozone is determined as excessive release of chlorine and bromine from man-made compounds such as chlorofluorocarbons (CFCs).

The release of Chlorofluorocarbons (CFCs) is the main reason for ozone layer depletion. CFCs are human-made chemicals that are commonly used in refrigerants, solvents, and aerosol sprays.

Impact of CFCs on the Ozone Layer:

1. Destruction of Ozone Molecules: CFCs are released into the atmosphere, where they are broken down by ultraviolet radiation, releasing chlorine atoms. These chlorine atoms then react with ozone molecules, breaking them down into oxygen molecules and destroying the ozone layer.

2. Reduction of Ozone Thickness: Ozone depletion leads to a reduction in the thickness of the ozone layer, allowing more harmful UV radiation to reach the Earth's surface. This can lead to several health problems such as skin cancer, cataracts, and weakened immune systems.

3. Global Warming: CFCs also contribute to global warming, as they are potent greenhouse gases that trap heat in the atmosphere.

Prevention of Ozone Depletion:

1. Ban on CFCs: The Montreal Protocol, signed in 1987, aims to phase out the production and consumption of ozone-depleting chemicals, including CFCs.

2. Use of Alternatives: Alternatives to CFCs, such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), have been developed. However, these also have a negative impact on the environment, and efforts are being made to find more sustainable alternatives.

3. Public Awareness: Awareness campaigns can help educate the public about the harmful effects of ozone depletion and encourage them to take steps to reduce their own CFC emissions.

In conclusion, the release of CFCs is the main reason for ozone layer depletion, which has negative impacts on human health and the environment. Efforts are being made to reduce CFC emissions and find sustainable alternatives to prevent further damage to the ozone layer.