Verbs

(v)tarnish, stain, maculate, sully, defilemake dirty or spotty, as by exposure to air; also used metaphorically“The silver was tarnished by the long exposure to the air”, “Her reputation was sullied after the affair with a married man”
(v)foul, befoul, defile, maculatespot, stain, or pollute“The townspeople defiled the river by emptying raw sewage into it”

Adjectives

(s)defiled, maculatemorally blemished; stained or impure
(s)maculatespotted or blotched