Sources of CFCs.
As aero-propellants cleaning solvent.
In fact food Packing.
In dry Cleaning Industries.
For sterilizing surgical instruments.
In medicinal and oral inhalation products.
For creating and degreasing electronic equipment.
Photochemistry of Ozone Depletion.
Chlorine is also ejected into the atmosphere by volcanic eruptions. A fraction of ejected chlorine reaches the ozonosphere. Oxides of nitrogen generally inactivate chlorine but the lowering of stratosphere temperature changes NO, into non-reactive nitric acid. Thus Cl or F is free to react with ozone, disintegrating it into O2 + O. Each atom of chlorine can destroy more than 1,00,000 molecules of ozone catalytically for converting O3 to O2.
The NO3 Cycle also gives the same result.
The chain reaction mentioned above takes about 40 years before the full effect is felt. The total ozone decreases by 6.5% during the chain. The natural concentration of ozone is maintained by the reversibility of O3, and O2, Due to man-made materials, the abundance of chlorine monoxide-ich air in the stratosphere goes on changing its concentration, This chlorine monoxide-rich with nascent oxygen and free chlorine is formed. This cycle continues and goes on destroying the ozone level.
Now it is strongly realised that unchecked, uncontrolled use of CFCs can create an ecological disaster for the world, CFCs cannot be removed from the atmosphere by the usual processes like photo-dissociation, rainfall, oxidation, etc.
Through the ozone holes, UV rays can travel through easily. The exhaust smoke of supersonic jets floats like thin clouds in the air. The CFCs in such closes react with sunlight to form smog. This raises the temperature of the atmosphere and also causes the thinning of the ozone layer.
Parameters of Ozone Destruction.
Effects of Ozone Holes.
The most significant effect of the ozone hole on human beings would be an increase in various skin cancers. Melanoma is a type of cancer that is malignant and can cause death. Two other types of skin cancers that are increasing are basal and squamous cell carcinomas. It is expected that every 1% loss is ozone leads to a 2% increase in diseases.
The UV rays coming to the earth’s surface can increase the incidence of cataracts and photokeratitis. The reason is that UV rays are easily absorbed by the lens and the cornea of the eye.
UV radiation may damage cell DNA. In this way, the genetic structure of humans, animals, and other organisms is damaged.