My children sometimes touch the the rim of the toilet bowl as shown in the above picture as they have no idea how dirty it is.
We often use "the lip/ rim of a cup/ a pot...".
I am not sure if it is correct to say "Do not touch the rim of the toilet" or "Do not touch the lip of the toilet"?
If we can't say that then do we have to say "Do not touch the edge of the toilet"?