title: Inorganic arsenic and basal cell carcinoma in areas of Hungary, Romania, and Slovakia: a case-control study.
abstract: BACKGROUND
  Inorganic arsenic (iAs) is a potent carcinogen, but there is a lack of information about cancer risk for concentrations < 100 μg/L in drinking water.
  
  
  OBJECTIVE
  We aimed to quantify skin cancer relative risks in relation to iAs exposure < 100 μg/L and the modifying effects of iAs metabolism.
  
  
  METHODS
  The Arsenic Health Risk Assessment and Molecular Epidemiology (ASHRAM) study, a case-control study, was conducted in areas of Hungary, Romania, and Slovakia with reported presence of iAs in groundwater. Consecutively diagnosed cases of basal cell carcinoma (BCC) of the skin were histologically confirmed; controls were general surgery, orthopedic, and trauma patients who were frequency matched to cases by age, sex, and area of residence. Exposure indices were constructed based on information on iAs intake over the lifetime of participants. iAs metabolism status was classified based on urinary concentrations of methylarsonic acid (MA) and dimethylarsinic acid (DMA). Associations were estimated by multivariable logistic regression.
  
  
  RESULTS
  A total of 529 cases with BCC and 540 controls were recruited for the study. BCC was positively associated with three indices of iAs exposure: peak daily iAs dose rate, cumulative iAs dose, and lifetime average water iAs concentration. The adjusted odds ratio per 10-μg/L increase in average lifetime water iAs concentration was 1.18 (95% confidence interval: 1.08, 1.28). The estimated effect of iAs on cancer was stronger in participants with urinary markers indicating incomplete metabolism of iAs: higher percentage of MA in urine or a lower percentage of DMA.
  
  
  CONCLUSIONS
  We found a positive association between BCC and exposure to iAs through drinking water with concentrations < 100 μg/L.
authors.affiliation: Centre for Radiation, Chemical and Environmental Hazards, Health Protection Agency, Chilton, United Kingdom.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Leonardi
authors.forename: Marie
authors.initials: M
authors.lastname: Vahter
authors.forename: Felicity
authors.initials: F
authors.lastname: Clemens
authors.forename: Walter
authors.initials: W
authors.lastname: Goessler
authors.forename: Eugen
authors.initials: E
authors.lastname: Gurzau
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
authors.forename: Rupert
authors.initials: R
authors.lastname: Hough
authors.forename: Kvetoslava
authors.initials: K
authors.lastname: Koppova
authors.forename: Rajiv
authors.initials: R
authors.lastname: Kumar
authors.forename: Peter
authors.initials: P
authors.lastname: Rudnai
authors.forename: Simona
authors.initials: S
authors.lastname: Surdu
authors.forename: Tony
authors.initials: T
authors.lastname: Fletcher
mesh_terms: D001151:Arsenic / Q000378:metabolism / Q000633:toxicity*; D002280:Basal Cell Carcinoma / Q000139:chemically induced* / Q000453:epidemiology; D016022:Case-Control Studies; D004781:Environmental Exposure; D006814:Hungary / Q000453:epidemiology; D016015:Logistic Models; D018570:Risk Assessment; D012307:Risk Factors; D012383:Romania / Q000453:epidemiology; D012878:Skin Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D018154:Slovakia / Q000453:epidemiology
chemical_list: D001151:Arsenic