I'll be interested in the responses to this as well. I have seen this color as well, though I haven't covered the glass with a book. I've seen where Jim says that the chlorine smell is normal coming from the mixture, he says it just cleans the air. I'm not crazy about breathing chlorine gas at any amount but it hasn't seemed to bother me in the big picture. I haven't noticed any white gas though. As far as I know, "it is OK" but maybe someone else will have more info, I've only been at it for 2-3 weeks.