Depletion of ozone is mainly due to chlorofluorocarbons (CFCs). These are synthetic chemicals which are used as refrigerants and in fire extinguishers. Carbon monoxide leads to air pollution. It causes harm to human by combining with haemoglobin, thus affecting `O_(2)` carrying capacity of blood. Methane is a greenhouse gas, released from power stations, chemical industries ect. pesticides are not degradable, thus causes biological magnification.
