Can chemical mutagens which enter the testis cause all the spermatogonial stem cells to mutate such that sperm will permanently contain the mutation?

Not likely. It may cause mutations in some or most but unlikely to damage "all" the stem cells. Unless there's a huge dose which would affect other parts of the body as well. As with everything in nature there are outliers that don't get affected or are severely effected by any given event.

Related Questions