there is definetly no problem with doing it. also some of the excess sodium will be washed away which is good. I used to do it all the time years ago when I was eating 4 cans a day.
Yeah, fitnessfrk is right on. It is great to do when consuming a nut load of tuna so you can reduce your sodium intake. It also helps to rinse chicken breasts before you cook them if you buy the "ice glazed" kind.