The reproducibility of self-reported exposure to asbestos and dust was examined in 116 male veterans who completed an initial mail survey and subsequent occupational clinic questionnaire a mean of 213 +/- 68 days later. For the 114 subjects who answered the asbestos question of the mail survey, 68 (60%) gave concordant replies, while 46 (40%) gave discordant answers later in the clinic. Of 51 subjects who answered yes to asbestos exposure in the clinic, 11 (22%) had answered no and 13 (26%) had answered not sure. Failure to note asbestos exposure could not be blamed exclusively on past, relatively low-level of exposure because many of the respondents had significant exposure histories. For dust exposure, 31 (29%) had discordant replies and 77 (71%) had concordant answers. Self-reported history of occupational exposure to asbestos and dust were not as reproducible as the smoking history and may be underreported when mail survey methods alone are used.