title: Cancer mortality and other causes of death in users of geothermal hot water.
abstract: BACKGROUND
  Residents of geothermal areas have increased incidence of non-Hodgkin's lymphoma, breast, prostate, and kidney cancers. The aim was to study whether this is also reflected in cancer mortality among the population using geothermal hot water for space heating, washing, and showering.
  
  
  METHODS
  The follow-up was from 1981 to 2009. Personal identifier of those 5-64 years of age was used in record linkage with nationwide death registry. Thus, vital and emigration status was ascertained. The exposed population was defined as inhabitants of communities with district heating generated from geothermal wells since 1972. Reference populations were inhabitants of other areas with different degrees of volcanic/geothermal activity. Hazard ratio (HR) and 95% confidence intervals (CI) were adjusted for age, gender, education, housing, reproductive factors and smoking habits.
  
  
  RESULTS
  Among those using geothermal water, the HR for all causes of death was 0.98 (95% CI 0.91-1.05) as compared with cold reference area. The HR for breast cancer was 1.53 (1.04-2.24), prostate cancer 1.74 (1.21-2.52), kidney cancer 1.78 (1.03-3.07), and for non-Hodgkin's lymphoma 2.01 (1.05-3.38). HR for influenza was 3.36 (1.32-8.58) and for suicide 1.49 (1.03-2.17).
  
  
  CONCLUSIONS
  The significant excess mortality risk of breast and prostate cancers, and non-Hodgkin's lymphoma confirmed the results of similarly designed studies in Iceland on cancer incidence among populations from high-temperature geothermal areas and users of geothermal hot water. The risk is not confined to cancers with good prognosis, but also concerns fatal cancers. Further studies are needed on the chemical and physical content of the water and the environment emissions in geothermal areas.
authors.affiliation: The Centre of Public Health Sciences, Faculty of Medicine, University of Iceland , Reykjavik , Iceland.
authors.forename: Adalbjorg
authors.initials: A
authors.lastname: Kristbjornsdottir
authors.forename: Vilhjalmur
authors.initials: V
authors.lastname: Rafnsson
mesh_terms: D000293:Adolescent; D000328:Adult; D001943:Breast Neoplasms / Q000401:mortality*; D002423:Cause of Death; D005260:Female; D045482:Hot Springs; D006801:Humans; D007055:Iceland / Q000453:epidemiology; D007251:Influenza, Human / Q000401:mortality*; D007680:Kidney Neoplasms / Q000401:mortality*; D008228:Lymphoma, Non-Hodgkin / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000401:mortality*; D012307:Risk Factors; D017678:Sex Distribution; D013405:Suicide / Q000706:statistics & numerical data*; D018707:Volcanic Eruptions / Q000009:adverse effects