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
As air pollution increases, symptoms of asthma worsen. Asthma's etiology is poorly understood and currently has no cure. There are many environmental factors that attribute to asthma. The main sources of environmental pollution are the burning of fossil fuels in the combustion engines, dust generated by traffic on road surfaces, and biomass used for cooking and heating. In urban areas, there are high concentrations of particulate matter, nitrogen dioxide, ozone, and other volatile organic compounds and can make breathing more difficult. The health effects of particulate matters with different diameters are related to the length of those particles staying in the atmosphere and the locations of infection in the respiratory tract Young children who are exposed to air pollution are extremely vulnerable. One reason they are more vulnerable is because the average breathing pattern for an adult is 16 to 20 breaths per minute, while a 1-year-old child has a faster breathing pattern which is 20 to 40 breaths per minute. Therefore, children will be inhaling more pollutants than adults.