African male in perfect health ingests arsenic (5)

I believe the answer is:

masai

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'african' is the definition.
(I've seen this before)

I don't understand how the remainder of the clue works.

(Other definitions for masai that I've seen before include "East African pastoralist" , "Highlander in Africa" , "Pastoral people of East Africa - as I am (anag)" , "East African people" , "Tribe in 5" .)

I've seen this clue in The Independent.

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