Contaminated (7)
'contaminated' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for unclean that I've seen before include "Dirty; immoral" , "Defiled" , "Dirty or unwashed" , "Foul" , "(Ritually) tainted" .)
(Other definitions for tainted that I've seen before include "Spoiled, stained" , "I attend to spoiled condition" , "Corrupted, sullied" , "Adulterated" , "Flawed, contaminated" .)