Particulate Matter is a complex mixture of extremely small particles and liquid droplets. It consists of a number of components, including acids (such as [[nitrates]] and [[sulfates]]), organic chemicals, metals, and soil or dust particles.
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'''Particulate Matter''' is a complex mixture of extremely small particles and liquid droplets. It consists of a number of components, including acids (such as [[nitrates]] and [[sulfates]]), organic chemicals, metals, and soil or dust particles.