LIVER AND LUNG TUMORS IN DOGS FROM "4,4'-METHYLENE-BIS(2-METHYLANILINE)

  • 1 January 1978
    • journal article
    • research article
    • Vol. 1  (3) , 339-356
Abstract
Six female beagle dogs were given, by capsule, a daily dose of 100 mg 4,4''-methylene-bis(2-methylaniline) [MeMDA], 3 times/wk for 6 wk, then 5 times/wk for 5 wk, at which time the dose was reduced to 50 mg 5 times/wk, continuously for periods up to 7.0 yr. Six female beagle dogs were kept as untreated controls for several studies and were sacrificed after 8.3-9 yr test. MeMDA dogs developed renal atrophy with an elevated blood urea nitrogen during an approximate 6 mo. period prior to death or being sacrificed in extremis. As 3 of 3 MeMDA dogs that survived for 5.2 yr-7.0 yr developed hepatocellular carcinomas and 2 of the 3 dogs also developed primary lung tumors, with no liver or lung tumor in 6 control dogs, MeMDA was considered to be carcinogenic for the dog [liver tumors: P < .05; lung tumors: P < .10; Fisher''s Exact Test, 1 tail].