I don't know anything about how toxic the processing of bamboo is, but I do know, from living in cotton growing country, that the defoliants that are sprayed on it before harvest are horrible, so if that is the reason you wouldn't use bamboo, you might want to rethink using cotton also. We also know that the making of polyester is a toxic process. I don't know what the conscientious consumer should do. Hobbs does make an organic cotton batting, I assume that means it is grown and processed safely. We probably need to check with the companies to see just how toxic the processing, etc.. really is.