THE production of bladder tumours by aromatic amines has been correlated with the excretion of ortho-hydroxylated metabolites (Clayson, 1962). In the case of 2-naphthylamine, Bonser, Clayson and Jull (1951) showed that the susceptibility of a species to bladder tumour induction on feeding this agent appeared to depend on the proportion of a dose metabolised to give 2-amino-1-naphthol and its conjugates. It was further shown that 2-amino-i-naphthol was highly carcinogenic upon implantation into the bladders of mice whilst the amine itself was only feebly carcinogenic under these circumstances (Bonser
