International Agency for Research on Cancer (IARC) - Summaries & Evaluations


VOL.: 16 (1978) (p. 325)

5. Summary of Data Reported and Evaluation1

5.1 Animal data

N-Phenyl-2-naphthylamine has been tested in mice by oral and single subcutaneous administration and in a small number of dogs by oral administration. Results of the experiment by oral administration in mice indicate a statistically significant increase in the incidence of all tumours, and in particular of hepatomas, in males of one of the two tested strains. In addition, subcutaneous administration of this compound produced a significant increase in the total incidence of tumours in females of one strain and of hepatomas in males of the other strain. These findings suggest that the compound is carcinogenic but do not allow a conclusive evaluation of the carcinogenicity of this compound to be made.

5.2 Human data

In one study, in one factory, of men with known exposure to N-phenyl-2-naphthylamine in rubber processing under controlled conditions, there was no indication of an excess incidence of bladder tumours. However, a broader study of rubber workers who had no exposure to 2-naphthylamine has shown an increased risk of bladder tumours. In the latter study, exposure was mixed but probably included exposure to N-phenyl-2-naphthylamine for many workers.

These findings do not permit an assessment of the presence or absence of an elevated risk for cancer of the urinary bladder in persons exposed to N-phenyl-2-naphthylamine.

1 Subsequent to the finalization of this evaluation by the Working Group in June 1977, the Secretariat became aware of an abstract of a paper by Checkoway et al. (1977) describing a retrospective cohort mortality study of bladder cancers in 4 major US rubber companies between 1964-1973; however, the study cannot be evaluated on the basis of the data presented.

Subsequent evaluation: Suppl. 7 (1987)

Last updated: 26 March 1998

    See Also:
       Toxicological Abbreviations
       N-Phenyl-2-naphthylamine  (IARC Summary & Evaluation, Supplement7, 1987)