title: Long-term dietary cadmium intake and cancer incidence.
abstract: BACKGROUND
  Cadmium, a ubiquitous environmental pollutant, is classified as a carcinogenic substance. Several laboratory and epidemiologic studies of workers and subjects in polluted areas have suggested a positive association between cadmium exposure and risk of several cancers. However, data from general populations are sparse. We prospectively examined the association between cadmium exposure and incidence of cancer in a Japanese population with a relatively high dietary intake of cadmium.
  
  
  METHODS
  We conducted a population-based prospective study in 90,383 Japanese men and women 45-74 years of age. Participants responded to a validated questionnaire that included 138 food items. We estimated dietary cadmium intake from 6 food groups, based on the questionnaire data. During 9 years of follow-up, 5849 cancer cases were identified. Hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer were calculated by Cox proportional hazards modeling.
  
  
  RESULTS
  There was no evidence of an association of cadmium consumption and total cancer, with HRs in the highest versus lowest cadmium intake group of 0.94 (95% CI = 0.82 to 1.08; test for trend, P = 0.46) for men and 0.96 (0.81 to 1.15; 0.60) for women. No site-specific cancers were associated with cadmium intake in men or women.
  
  
  CONCLUSIONS
  We found no associations of cancer with cadmium, at least at the exposure levels observed in a general population in Japan.
authors.affiliation: Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan. nsawada@ncc.go.jp
authors.forename: Norie
authors.initials: N
authors.lastname: Sawada
authors.forename: Motoki
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Manami
authors.initials: M
authors.lastname: Inoue
authors.forename: Ribeka
authors.initials: R
authors.lastname: Takachi
authors.forename: Shizuka
authors.initials: S
authors.lastname: Sasazuki
authors.forename: Taiki
authors.initials: T
authors.lastname: Yamaji
authors.forename: Taichi
authors.initials: T
authors.lastname: Shimazu
authors.forename: Yoko
authors.initials: Y
authors.lastname: Endo
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Tsugane
mesh_terms: D000328:Adult; D000368:Aged; D002104:Cadmium / Q000032:analysis / Q000633:toxicity*; D004034:Diet Surveys; D005260:Female; D005500:Follow-Up Studies; D005506:Food Contamination / Q000032:analysis; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009369:Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012042:Registries; D011795:Surveys and Questionnaires
chemical_list: D002104:Cadmium