Environment of Pakistan
The Air pollution is the release of chemicals and particulates into the atmosphere. Common gaseous pollutants include carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs) and nitrogen oxides produced by industry and motor vehicles. Photochemical ozone and smog are created as nitrogen oxides and hydrocarbons react to sunlight. Particulate matter, or fine dust is characterized by their micrometre size PM to PM. The air in Karachi is rapidly polluted by automobile smoke, especially Rickshaws and Buses, industrial emissions, open burning of garbage, house fires, and other particles but the government and environment organizations seems non-serious to tackle the issue timely.
The two-stroke engines on rickshaws and motorcycles are one of the major polluters of air in Karachi and the rest of Pakistan. The two-stroke engines as well as defective or unturned vehicles are major polluters with carbon dioxide emissions. Two-stroke engines as well as defective vehicles using substandard lubricant are major emitters of sulfur dioxide and smoke. Automobiles operating on compressed natural gas and liquefied petroleum gas are major air polluters.
National Emissions Standards Act
The six common air pollutants of primary concern to the United States are particle pollution, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. These pollutants are detrimental to health, the environment, and a person's home and other belongings. The worst two of the six pollutants are particle pollution and ground-level ozone, which have to be regulated by the EPA. Particle pollution, or particle matter, consists of soot, smoke, and chemically formed "droplets". These particles are very small and can bury themselves deep inside the lungs. Ground-level ozone is found in smog and can also negatively affect the lungs. Smog contains volatile organic compounds (VOCs) and nitrogen oxides (NOx). VOCs come from cars burning gasoline, petroleum refineries, chemical manufacturing plants, etc., while NOx results from burning gasoline, coal, or oil.