Lung cancer and arsenic exposure in drinking water: a case-control study in northern Chile.
In some Chilean cities, levels of arsenic (As) in drinking water reached 800 (micrograms/L between 1950 and 1970, while current levels are 40 (micrograms/L. To evaluate the causal role of this exposure in lung and bladder cancers, we conducted a case-control study in Regions I, II, and III of the country. From 1994 to 1996, cases diagnosed as lung cancer and two hospital controls were entered in the study; one control was a patient with a cancer, while the other was a patient without cancer, both conditions unrelated to As. Controls were matched with cases by age and sex. A standard survey containing questions about residence, employment, health history, was administered to study subjects. Data on As concentrations in water were obtained from records of the municipal water companies. A total of 151 lung cancer cases and 419 controls (167 with cancer and 242 without cancer) were enrolled. Median level of lifetime As exposure was significantly higher among cases, with a clear dose-response relationship between mean As exposure levels, with an OR (95% CI) of: 1, 1.7 (0.5-5.1), 3.9 (1.2-13.4), 5.5 (2.2-13.5), and 9.0 (3.6-22) for strata one to five respectively. This study provides new evidence that As in drinking water can cause internal cancers and gives an estimate of the form of this relationship.
Ferreccio
C
C
Grupo para el Desarrollo de la Investigación en Salud (GREDIS). Casilla 52750, Correo Central, Santiago, Chile.
González Psych
C
C
Milosavjlevic Stat
V
V
Marshall Gredis
G
G
Sancha
A M
AM
D001151:Arsenic / Q000009:adverse effects* / Q000032:analysis; D002274:Carcinogens, Environmental / Q000009:adverse effects* / Q000032:analysis; D016022:Case-Control Studies; D002677:Chile / Q000453:epidemiology; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D008297:Male; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014505:Urban Population / Q000706:statistics & numerical data; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000032:analysis; D014881:Water Supply / Q000032:analysis / Q000706:statistics & numerical data
D002274:Carcinogens, Environmental; D014874:Water Pollutants, Chemical; D001151:Arsenic