Failure of pure 1-naphthylamine to induce bladder tumors in dogs.

1-Naphthylamine was administered p.o. to beagles for approximately 9 years at a daily dose of 15 mg/kg (5 days a week).

Di(4-aminophenyl)-methane (MDA): 4-7 year dog feeding study.

9 pure bred female beagles ingested purified or crude MDA (in 70 mg doses on 3 days of the week) over periods ranging from 3 years, 11 months to 7 years, 2 months. Total quantities of MDA ingested ranged from 39.98 g to 66.

Liver cancer deaths in the continental USA from 1930 to 1972.

Since 1944 the general U.S. population has been absorbing organochlorine pesticides, which have recently been largely banned because of a concern that they would cause or contribute to the production of liver cancer.