Curried pimento wraps a possible cause of illness (8)
I believe the answer is:
ptomaine
'possible cause of illness' is the definition.
(chemical once thought to cause food poisoning)
'curried pimento wraps a' is the wordplay.
'curried' is an anagram indicator (curry could historically mean to beat).
'wraps' is an insertion indicator (inserted letters get wrapped up).
'pimento' with letters rearranged gives 'ptomine'.
'ptomine' placed around 'a' is 'PTOMAINE'.
(Other definitions for ptomaine that I've seen before include "Pain to me (anag.)" , "A pimento might turn to food poisoning" , "stuff of death?" , "Old term for food poisoning" , "Food poisoning from rotten substances" .)