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'''Pollution''' is contamination of a system with harmful foreign components.<ref>http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=pollution</ref>. The most common usage of the word pollution refers to [[environmental pollution]], which is contamination of the air, ground, or water with harmful chemicals. A less common use is noise pollution, which is "contamination" of a quiet space by annoying sounds.

'''Pollution''' is contamination of a system with harmful foreign components.<ref>http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=pollution</ref>. The most common usage of the word pollution refers to [[environmental pollution]], which is contamination of the air, ground, or water by harmful chemicals or particulate matter. A less common use is noise pollution, which is "contamination" of a quiet space by annoying sounds.

==References==

==References==