Dietary arsenic intake and subsequent risk of cancer: the Japan Public Health Center-based (JPHC) Prospective Study

Arsenic is a known human carcinogen and has been linked to adverse health outcomes, including cancer. However, the effects of arsenic exposure from food on health are still unknown. We researched to examine the association between arsenic exposure from food and incidence of cancer in a Japanese population. We conducted a population-based prospective study in 90,378 Japanese men and women aged 45-74 years. Participants responded to a validated questionnaire that included 138 food items. We estimated dietary arsenic intake from 12 food groups (75 items) based on the questionnaire data. During 11 years of follow-up, 7,002 cancer cases were identified. Hazard ratios (HRs) and 95 % confidence intervals (CIs) for cancer were calculated by Cox proportional hazards modeling. Total arsenic and inorganic arsenic showed no association with the risk of total cancer in both men and women. Total arsenic and inorganic arsenic intake tended to be associated with an increased risk of lung cancer in men. In particular, these positive associations were strengthened in currently smoking men, with HRs (95 % CI) in the highest categories of arsenic and inorganic arsenic intake compared with the lowest of 1.29 (95 % CI = 1.03-1.61) and 1.36 (95 % CI = 1.09-1.70), respectively. We also detected an interaction between arsenic and inorganic arsenic intake and smoking status in men (p (interaction) < 0.01 and 0.07, respectively). A significant dose-response trend was seen in the association of arsenic and inorganic intake with lung cancer risk in currently smoking men.