Incidence of transitional cell carcinoma of the bladder and arsenic exposure in New Hampshire.
OBJECTIVE
Arsenic is a known bladder carcinogen and populations exposed to high arsenic levels in their water supply have reported elevated bladder cancer mortality and incidence rates. To examine the effects of lower levels of arsenic exposure on bladder cancer incidence, we conducted a case-control study in New Hampshire, USA where levels above 10 micro/l are commonly found in private wells.


METHODS
We studied 383 cases of transitional cell carcinoma of the bladder cancer, newly diagnosed between July 1, 1994 and June 30, 1998 and 641 general population controls. Individual exposure to arsenic was determined in toenail clippings using instrumental neutron activation analysis.


RESULTS
Among smokers, an elevated odds ratio (OR) for bladder cancer was observed for the uppermost category of arsenic (OR: 2.17, 95% CI: 0.92-5.11 for greater than 0.330 mcg/g compared to less than 0.06 micro/g). Among never smokers, there was no association between arsenic and bladder cancer risk.


CONCLUSIONS
These, and other data, suggest that ingestion of low to moderate arsenic levels may affect bladder cancer incidence, and that cigarette smoking may act as a co-carcinogen.
Department of Community and Family Medicine, Norris Cotton Cancer Center, Dartmouth Medical School, Lebanon, NH 03756, USA. margaret.karagas@dartmouth.edu
Margaret R
MR
Karagas
Tor D
TD
Tosteson
J Steven
JS
Morris
Eugene
E
Demidenko
Leila A
LA
Mott
John
J
Heaney
Alan
A
Schned
D000328:Adult; D000368:Aged; D001151:Arsenic / Q000009:adverse effects*; D002273:Carcinogens / Q000009:adverse effects*; D002295:Carcinoma, Transitional Cell / Q000453:epidemiology* / Q000209:etiology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009513:New Hampshire / Q000453:epidemiology; D016017:Odds Ratio; D012042:Registries / Q000706:statistics & numerical data*; D012907:Smoking / Q000009:adverse effects; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D014881:Water Supply
D002273:Carcinogens; D001151:Arsenic