“…The conversion of aldrin (1,2,3,4,10, 10-hexachloro-l,4,,4a,5,8,8a-hexahydro-1,4-endo -exo-5,8 -dimethanonaph thalene) to dieldrin in mammals was first observed by Barnes as reported by Winter-ingham and Barnes (76), and the conversion was later confirmed by others (7). Using houseflies, Brooks (5) not only demonstrated the metabolism of aldrin to dieldrin and isodrin to endrin, but also obtained data that indicated further degradation of endrin to its known keto rearrangement product (3).…”