Acid rain Acid rain Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids. Some governments have made efforts since the 1970s to reduce the release of sulphur dioxide and nitrogen oxide into the atmosphere with positive results. Nitrogen oxides can also be produced naturally by lightning strikes, and sulphur dioxide
Nitrogen dioxide poisoning The standards also based on the concentration of nitrogen dioxide that show a significant and profound effects on the function of the pulmonary of asthmatic patients. Historically, some cities in the United States including Chicago and Los Angeles have high levels of nitrogen dioxide but the EPA set a standard values less than 100 ppb for a one-hour exposure and less than 53 ppb for chronic exposure. Nitrogen dioxide poisoning is not harmful to all forms of life just like "chlorine gas poisoning" and carbon monoxide poisoning. It is easily absorbed through the lungs and its inhalation result in heart