Dangerous element from artist fellow (5)
I believe the answer is:
radon
'dangerous element' is the definition.
(radioactive chemical element)
'artist fellow' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'fellow' becomes 'don' (both can mean an academic).
'ra'+'don'='RADON'
'from' is the link.
(Other definitions for radon that I've seen before include "Gaseous element, Rn" , "hazardous substance" , "gets no reaction" , "Element, symbol Rn" , "Rare noble gas" .)