Use of Calcium Hypochlorite in Pools and Hot Tubs

I am trying to get the Houston area YMCAs to use Calcium Hypochlorite instead of Sodium Hypochlorite in their pools and did a google search and the articles kept saying that there was no difference in toxicity between the two. We know that is not the case but I need scientific proof that Calcium Hypo is safer. Does anyone have any good references for this?
Also, my stepdad was wondering if he could mms in his hot tub. Or is Calcium Hypochlorite better? Thanks, Emily

Hi Emily. Yes he could add MMS to the hot tub, but it won't last long. @ 103f the MMS will gas off in less than an hour whereas the calcium hypochlorite stays in solution.