As I was bringing indoors some of the stuff in my pool shed in for the winter, I noticed that a couple of unopened bleach bottles seem to be bloated, like they are rounded in shape. It is fall in Chicago, but we've hardly had any extreme weather to this point. Any ideas what would cause this? Or more importantly, what I should do about it? I am afraid if I open them I will get a bleach blast in the eye or something, but also afraid if I leave them they may split.