It can be carried via country to country (internationally) by the wind, which causes pollution to spread. Rain can remove air pollution, causing soil and water pollution. Sunlight can help to convert air pollution into a variety of things. Air pollution is caused by human and natural resources. Although most air pollution problems are caused by local or regional sources, air pollution is not limited to national borders. Some air pollutants are known to spread around the world and are stored in bodies of water and water away from their sources.
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