That's why I've been hesitant to switch over to essential oils instead of FO's. My own knowledge of herbs tells me that some are just inherently dangerous, especially to children, pets and pregnant women. But I was hoping someone here might have knowledge of actual research that has been done with regard to burning EO's. I'm thinking it might be a valid concern because of what happens when a gardener accidentally burns some poison oak or poison ivy in his leaf pile. Inhaling the smoke could land him in the hospital...or worse. Still, I've seen EO "burners" in health-food stores, where the oil is suspended over a tealight so it can vaporize into the air and scent your home. Seems kind of risky to me. Sounds good to me. I think I'll save my FO's and EO's for making "scent bead" sachets. They lightly scent a room without actually having to burn something, and no one breathes enough of it to get sick.