I have no idea if they are. I imagine it would be fine over the heater, since its actually made for reptiles, they had to assume someone would put it near a heat source.

I accidentally cover my frogs in calcium all the time. -_- They just sit there and wait for me to wash it off now, lol.

As for the baby food, I get ... I think its Earthland's Best Organic chicken and rice. The only stuff in there is chicken, squash, and rice. Granted, squash and rice isn't in his natural diet, but I can't imagine either of them would hurt his digestion, especially in the small amount he would be eating.