Cashews grow dangling from the bottom of a fruit, and their raw shell is toxic.
Each cashew nut hangs beneath a swollen, pear-shaped cashew apple. The shell around the nut contains an oil related to the irritant in poison ivy, which is why cashews are always sold shelled and roasted or steamed.
Why is this true?
The cashew belongs to the same plant family as poison ivy, mango and pistachio. Processing removes the irritant, but workers who shell cashews by hand often suffer skin burns.
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