This has been discussed before - just recently - do a search on it.
The risk of the "other things" that go down the toilet and CANNOT be removed is high.
Trace minerals - not always good ones, chemicals, prescription and illegal drugs and the like.
There are several studies that have come out of universities that state the risk might be high enough to not take the reward of cheap and often free fertilizer.
Personally I will not have it on the place and I have stopped buying hay from a neighbour that has used it.
If you have customers buying your beef ask them if they like it in their meat.
It is a free world - well sort of, but I know more than a few who stay away from it - myself included. And I will not knowingly buy from anyone who uses it.
Bez