Sir: Chlorofluorocarbon (CFC) is an organic compound that contains carbon, chlorine and fluorine, produced as a volatile derivative of methane and ethane. In the past, it was frequently used in refrigerators, air conditioners, deodorants and in cleaning products. Since scientists have discovered that CFC causes depletion of the ozone layer, it has been abandoned in the modern world. CFC can make a negative impact on human health and the environment. CFC enters the body through the inhalation of air, but sometimes it can be consumed by drinking contaminated water. The inhalation of high levels of CFC can damage our skin, nervous system, brain, heart, lungs, liver and kidney. The exposure of extremely high levels of CFC may even lead to the death of a person. The ingestion of CFC leads to nausea, diphtheria and irritation of the digestive tract. It also damages plants and contributes to global warming. The government should ensure that such elements are completely discarded in order to maintain a better environment. FARWA SAJJAD Karachi