International Agency for Research on Cancer (IARC) - Summaries & Evaluations
N-PHENYL-2-NAPHTHYLAMINE
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