Up here in the cold NE most places like West Marine carry 3 flavors of 'antifreeze'. The pink at -50 degrees or blue -100 for your potable water systems and the Purple at -60 * with rust inhibitors ect... * for your engine. All three are environmentally friendly and not poisenous. Different companies have different degrees of protection and colors but if possible look for the rust inhibitor stuff for your engine if availible. If not don't worry that much about it many people I know have used the pink in thier engines for many years (before the engine specific safe stuff was around) without a problem.
Wickford/Narragansett Bay RI