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.
Air pollution in the United States
Even though the mechanistic association between air pollution and infections is still unclear and require further research, some studies shows that the some air pollutants, including secondhand smoking, ozone (O), particulate matter (PM), and nitrogen dioxide (NO), may cause the infections. According to the Consumer Product Safety Commission (CPSC), children have higher risk of lower respiratory tract infections, such as pneumonia and bronchitis, if their parents smoke. CPSC mentions that 150,000 to 300,000 children (under 18 month) are affected by the lower respiratory tract infections which leads to 7,500 to 15,000 hospitalizations each year based on the EPA estimation. Exposure to higher level NO2 or long term exposure to low level NO2 also leads to higher risk for infections.