Ok I called Morgan Composting that makes dairy doo and a bunch of other products. Before I new it I was talking to Brad Morgan the president,that kind of thing usually never happens when you call a company. He told me they do constant testing and there is slight chance you could get a batch that could harm the worms but unlikely. They sell worm castings and use dairy doo to feed their own worms,and I found out they even sell worms at $22 a pound. They use about a 30% mix of dairy doo with their worms and only use dairy cattle calves for their source of manure because of the controlled diet their fed,make a more consistent compost. I've been using their products since last year and they seem very good. I had my mix a little hot so I just got done mixing in a little more paper and some coco coir,worms seem happy.