1540s, "one who renders unclean or impure, one who profanes," agent noun from pollute (v.). Ecological sense is by 1958.
Entries linking to polluter
pollute v.
late 14c., polluten, "to defile, violate the sanctity of, render ceremonially unclean," a back formation from pollution, or else from Latin pollutus, past participle of polluere "to defile, pollute, contaminate." Related: Polluted; polluting. Meaning "make physically foul" is from 1540s; specific sense "contaminate the environment" emerged by 1860, but was not yet in the 1895 Century Dictionary.