I just started using store bought ZooMed sphagnum moss with my toads and they seem to like it. Took them some getting used to first but it does do a good job keeping the terrarium damp. It made the room smell terrible for the first few hours but it aired out pretty quick.

I think store bought would be the safest option as far as bacteria goes but that's just my estimate. It's worth mentioning that when I opened my box I found a live stick bug in the moss (The box does say it's all-natural, so...).