title: Mortality and cancer incidence among a population previously exposed to environmental cadmium.
abstract: OBJECTIVE
  This paper evaluates the associations of previous exposure to environmental cadmium (Cd) and renal function with total mortality and cancer incidence.
  
  
  METHODS
  The study population comprised 275 residents (aged 40-92 years at baseline) in a Cd-polluted area located on Tsushima Island, Nagasaki, Japan. In the study area, the dietary intake of Cd decreased because the soil of the Cd-polluted rice fields was replaced with new soil between 1980 and 1983. The mortality rate from 1982 to 1997 and cancer incidence from 1985 to 1996 were investigated. Standardized mortality and incidence ratios (SMR and SIR) were calculated by using regional reference rates. The associations of renal function and urinary Cd levels with total mortality and cancer incidence were evaluated with Cox regression models.
  
  
  RESULTS
  The SMR for all subjects, and those with a urinary beta2-microglobulin (U-beta2M) concentration > or = 1,000 microg/g creatinine (Cr) and < 1,000 microg/g Cr was estimated at 90 [95% confidence interval (CI) 73-109], 138 (95% CI 101-183) and 66 (95% CI 49-87), respectively. After adjustment for age and other potential confounders, in men, serum beta2M (S-beta2M) (> or = 2.3 mg/l) and in women, serum Cr (> or = 21.2 mg/ 100 ml), relative clearance of beta2M (> or = 21%) and U-beta2M (> or = 1,000 microg/g Cr), were associated with a significantly increased risk of mortality, with hazard ratios exceeding 2.0. After further adjustment for log(U-beta2M), the rate ratio of deaths associated with, in men, increased S-beta2M was 2.53 (95% CI 0.97-6.65) and, in women, increased serum Cr (S-Cr) concentrations was 2.75 (95% CI 1.24-6.14). Urinary Cd concentrations (> or = 10 microg/g Cr) were not significantly associated with mortality. The overall SIR of all malignant neoplasms was 71 (95% CI 44-107).
  
  
  CONCLUSIONS
  These findings suggest that renal tubule dysfunction and a reduced glomerular filtration rate are predictors of mortality among persons previously exposed to environmental Cd. However, the results also suggest that overall mortality rates in Cd-polluted areas are not necessarily increased, because of the low mortality among those with no, or only slight, signs of low-molecular weight proteinuria. Overall cancer incidence may not be increased among residents in Cd-polluted areas.
authors.affiliation: Department of Preventive Medicine and Health Promotion, Nagasaki University School of Medicine, Sakamoto, Nagasaki, Japan. k-iwata@net.nagasaki-u.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Arisawa
authors.forename: A
authors.initials: A
authors.lastname: Nakano
authors.forename: H
authors.initials: H
authors.lastname: Saito
authors.forename: X J
authors.initials: XJ
authors.lastname: Liu
authors.forename: M
authors.initials: M
authors.lastname: Yokoo
authors.forename: M
authors.initials: M
authors.lastname: Soda
authors.forename: T
authors.initials: T
authors.lastname: Koba
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Kinoshita
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002104:Cadmium / Q000009:adverse effects*; D002423:Cause of Death; D015331:Cohort Studies; D004785:Environmental Pollutants / Q000009:adverse effects*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007564:Japan; D007684:Kidney Tubules / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009369:Neoplasms / Q000139:chemically induced* / Q000453:epidemiology*; D012737:Sex Factors
chemical_list: D004785:Environmental Pollutants; D002104:Cadmium