title: Cardiovascular disease and arsenic exposure in Inner Mongolia, China: a case control study.
abstract: BACKGROUND
  Millions of people are at risk from the adverse effects of arsenic exposure through drinking water. Increasingly, non-cancer effects such as cardiovascular disease have been associated with drinking water arsenic exposures. However, most studies have been conducted in highly exposed populations and lacked individual measurements.
  
  
  OBJECTIVE
  To evaluate the association between cardiovascular disease and well-water arsenic exposure.
  
  
  METHODS
  We conducted a hospital based case control study in Inner Mongolia, China. Cases and controls were prospectively identified and enrolled from a large hospital in the Hangjin Hou area. Cases were patients diagnosed with cardiovascular disease and controls were patients free from cardiovascular disease, admitted for conditions unrelated to arsenic exposure. Water from the primary water source and toenail samples were collected from each subject and tested for inorganic arsenic.
  
  
  RESULTS
  Arsenic exposures were moderate with mean and median arsenic exposures of 8.9 μg/L and 13.1 μg/L, respectively. A total of 298 cases and 275 controls were enrolled. The adjusted odds ratio (AOR) and corresponding 95% confidence interval (95% CI) for a 10 μg/L increase in water arsenic were 1.19 (95% CI: 1.03, 1.38). Compared to exposures less than 10 μg/L, the AOR for water arsenic exposures above 40 μg/L was 4.05 (95% CI: 1.1-14.99, p = 0.04). Nail arsenic above 1.38 μg/g was also associated with an increased risk of cardiovascular disease.
  
  
  CONCLUSIONS
  By using standardized case definitions and collecting individual measurements of arsenic, this study addressed several limitations of previous studies. The results provide further evidence of the association between cardiovascular disease and arsenic at moderate exposures.
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, Chapel Hill, North Carolina, USA. wade.tim@epa.gov.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Wade
authors.affiliation: Inner Mongolia Centers for Endemic Disease Control and Research, Huhhot, Inner Mongolia, China. yajxia@126.com.
authors.forename: Yajuan
authors.initials: Y
authors.lastname: Xia
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, Chapel Hill, North Carolina, USA. jmumford5@gmail.com.
authors.forename: Judy
authors.initials: J
authors.lastname: Mumford
authors.affiliation: Inner Mongolia Centers for Endemic Disease Control and Research, Huhhot, Inner Mongolia, China. wkg1959@163.com.
authors.forename: Kegong
authors.initials: K
authors.lastname: Wu
authors.affiliation: University of Alberta, Edmonton, Alberta, Canada. xc.le@ualberta.ca.
authors.forename: X Chris
authors.initials: XC
authors.lastname: Le
authors.affiliation: United States Environmental Protection Agency, Office of Research and Development, Chapel Hill, North Carolina, USA. sams.elizabeth@epa.gov.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Sams
authors.affiliation: University of North Carolina, Chapel Hill, North Carolina, USA. wesanders@me.com.
authors.forename: William E
authors.initials: WE
authors.lastname: Sanders
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001151:Arsenic / Q000633:toxicity*; D002318:Cardiovascular Diseases / Q000139:chemically induced / Q000453:epidemiology*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D060766:Drinking Water / Q000032:analysis*; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D060986:Water Wells; D055815:Young Adult
chemical_list: D060766:Drinking Water; D014874:Water Pollutants, Chemical; D001151:Arsenic