When one sits on a flush toilet to relieve himself, pure water which comes out from the water supply falls onto the impure water at the bottom of the bowl and this causes the water to splash. Drops of the water that is splashed sometimes touch one's body. Does this render the body impure?

All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

Flowing water that is mixed with impure water is considered impure. Impurity of that water is certain because it is stagnant water that is mixed with impurity and they can not be separated. Therefore, it is obligatory to avoid it. When that water touches either one’s garment or body, the affected part must be washed. Allaah Almighty says (what means): {And your clothing purify.} [Quran 74: 4]

Allaah Knows best.