Dietary acrylamide intake and the risk of head-neck and thyroid cancers: results from the Netherlands Cohort Study.

Acrylamide exposure has been related to an increased incidence of oral and thyroid tumors in animal studies. In 1986, 120,852 persons (aged 55-69 years) were included in the Netherlands Cohort Study. Dietary acrylamide intake was assessed with a food frequency questionnaire and was based on chemical analysis of all relevant Dutch foods. Hazard ratios were adjusted for smoking and other confounders. After 16.3 years of follow-up, there were 101, 83, 180, and 66 cases of oral cavity, oro-hypopharynx, larynx, and thyroid cancer, respectively. Average daily dietary acrylamide intake was 21.8 microg (standard deviation, 12.1). Dietary acrylamide intake was not associated with increased risk of oral cavity (hazard ratio (HR) per 10-microg intake/day = 0.90, 95% confidence interval (CI): 0.73, 1.10), oro-hypopharynx (HR = 0.74, 95% CI: 0.53, 1.03), larynx (HR = 1.05, 95% CI: 0.91, 1.21), or thyroid (HR = 1.03, 95% CI: 0.82, 1.27) cancer. For nonsmokers, hazard ratios were not increased either. Dietary acrylamide was statistically significantly associated with increased risk of oral cavity cancer in female nonsmokers, but case numbers were small. Dietary acrylamide intake was not positively associated with risk of head-neck and thyroid cancer, except with oral cavity cancer risk for female nonsmokers. A negative association for males was indicated.