Why can't I find cashews in the shell?

My Friend Matt:

Why don't I ever see cashews in the shell? Do cashews have shells? Peanuts in the shell are cheaper than peanuts out of the shell, so wouldn't cashews be? Why can't I buy them that way? I'd be willing to crack them myself.

-- Nutty on the net

You'd make it through maybe the first dozen, but then you'd have to stop and search frantically for your car keys so you could get yourself to the emergency room. Long ago the U.S. passed laws against importing the nuts in their shells (all cashews sold here are imported from China, India, or Brazil). On the hoof, they're toxic.

Cashew grove: Imagine a tree covered with small, yellow-red apples. From the bottom of each grows something that looks like an inflated lima bean. That's the nut. It has a thick outer shell and thin, membranous inner shell, between which is an oily liquid that is quite irritating and potentially toxic. When cashews are processed, the outer shell is removed, the liquid drained off, the nuts are dried, and the membrane shell is removed, and the detoxed nuts are packed in tins for export. The oily liquid is recycled into bug spray. Lurking in the branches of the cashew's family tree are a couple of nasty relatives: poison oak and poison ivy.