From what I see on the Purinize site, I wouldn't touch the stuff. I think that it is probably Alum in water solution. A lot of claims, no proof. If it is Non-Toxic, it won't kill pathogenic bacteria or protozoans. Flocculants are not disinfectants. Alum is cheap and readily available, although you might have to go to a farm store to find it. Settling and decanting can reduce the disinfectant demand or help prevent filter clogging. It will require carrying more stuff, which may be worthwhile if turbidity is a real problem.

http://www.iwapublishing.com/news/simple-options-remove-turbidity