BACKGROUND: From 1950 to 1990 pentachlorophenol (PCP) was used widely in the New Zealand sawmill industry, and persistent claims of long-term health effects have been made. METHODS: We surveyed surviving members of a cohort enumerated to study mortality in sawmill workers employed from 1970 to 1990. Estimates of historical exposure were based on job titles held, using the results of a PCP biomonitoring survey conducted in the 1980s. The survey involved interviews and clinical examinations, with interviewers and examiners blinded to exposure status. RESULTS: Of the 293 participants 177 had not been exposed, and of the 116 exposed all but 10% had low or short-term PCP exposure. Nevertheless, a number of significant associations between PCP exposure and the prevalence of various symptoms were observed including associations between: (i) exposure levels and self-reported tuberculosis, pleurisy or pneumonia (P < 0.01) and a deficit in cranial nerve function (P = 0.04); (ii) duration of employment and thyroid disorders (P = 0.04), and neuropsychological symptoms including often going back to check things (P = 0.04), low libido (P = 0.02) and heart palpitations (P = 0.02), and a strong dose-response trend for frequent mood changes without cause (P < 0.01); and (iii) cumulative exposure and frequent mood changes without cause (P = 0.02), low libido (P = 0.04), and in the overall number of neuropsychological symptoms reported (P = 0.03). CONCLUSIONS: PCP exposure was associated with a number of physical and neuropsychological health effects that persisted long after exposure had ceased.