Even the human factor in testing these substances can have problems. While I never did actually chip anything on the frozen component, I have had my share of very bad ice cubes. I think they can get rotten as they age, and become toxic.

You can tell when you get a bad one or two. You wake up in the morning with a headache, nausea, and general malaise. It's really miserable, usually lasts less than a day.

Even humans have limitations. At one time I would have strongly suggested Raoul send a case of whatever to me for qualative analysis, followed by quantative analysis, probably followed by a case of VBIC, or Very Bad Ice Cubes.

Arf