Consider the following statements regarding depletion of the ozone layer: 1. Excessive release of chlorine and bromine in the environment from man-made compounds, such as chlorofluorocarbons. 2. Occurrence of certain natural phenomena such as sunspots, and stratospheric winds. 3. Degradation of materials by ultra-violet radiation 4. Major volcanic eruptions. Which of the above can be categorized as causing ozone depletion? Correct Answer 1, 2 and 4 only Causes of Ozone Layer Depletion: Excessive release of chlorine and bromine from man-made compounds such as chlorofluorocarbons (CFCs). CFCs (chlorofluorocarbons), halons, CH3CCl3 (Methyl chloroform), CCl4 (Carbon tetrachloride), HCFCs (hydro-chlorofluorocarbons), hydrobromofluorocarbons and methyl bromide are found to have a direct impact on the depletion of the ozone layer. These are categorized as ozone-depleting substances (ODS). Natural phenomena such as Sunspots and stratospheric winds. Major volcanic eruptions. Effects of ozone depletion: Damage to human health: Humans will be overly exposed to strong UV light. Overexposure to strong UV light causes skin cancer, cataract in eyes, sunburns, weakening of immune system and quick ageing. Devastation to the environment: Many crops species are vulnerable to strong UV light and overexposure may well lead to minimal growth, photosynthesis and flowering. Forests equally bear the brunt of ozone depletion. Threat to marine life: Certain species of marine life have been greatly affected by overexposure to ultraviolet radiation at their early stage. Effect on animals: In domesticated animals, too much ultraviolet radiation could also lead to skin and eye cancer. Effect on certain materials: Materials like plastics, wood, fabrics, rubber is massively degraded by too much ultraviolet radiation. Effect on forests: The productivity of forests will get reduced.