Air pollution is the introduction of harmful substances into the atmosphere, which can cause health issues and environmental damage. It is caused by the burning of fossil fuels like coal and petroleum, which release nitrogen, sulfur, and particulate matter. This can produce smog and acid rain. Regular inhalation of these polluted air can increase risks of diseases like asthma, COPD, and lung cancer. Governments have made efforts to reduce sulfur dioxide emissions with some success, but air pollution remains a threat, especially to children and the elderly. Reduction efforts include embracing cleaner transportation, fuels, production, and increasing green spaces.