Ruling on doing wudoo’ with water that is contaminated but not naajis (ritually impure)
Question

                I would like to know whether it is allowed for a person to use water that maybe unclean for wudu.  What if the water is not suitable for drinking due to it being unclean, can one rinse their mouth out with this water?
Praise be to Allah.This 
          question was answered for us by Shaykh ‘Abd-Allaah ibn Munayyi’, who 
          said:
“One 
          of the basic principles of sharee’ah is the hadeeth of the Messenger 
           (peace and blessings of Allaah 
          be upon him), who said: ‘There should be neither harming nor reciprocating 
          harm.’ Part of this principle is that the Muslim is not permitted to 
          harm himself, which includes not using contaminated water for doing 
          wudoo’.
So it 
          is forbidden to do wudoo’ using contaminated water, but if a person 
          does do wudoo’ using such water his wudoo’ is still valid, because it 
          is not naajis (ritually impure), but his action is haraam because he 
          is harming himself. And Allaah knows best.”