Biochemistry is most succinctly described as "organic chemistry using an aqueous solvent.". Each cell is essentially a little bag of water, with various molecules and ions floating in it. Much of biochemistry is dependent on the relative concentrations of these ions, and when there's two much...
I'm not a lawyer, but don't most liability releases discuss potential risks? Perhaps the plaintiffs would have to prove gross negligence, but this might well be provable.