Increased incidence of malignancies in Sweden after the Chernobyl accident--a promoting effect?
BACKGROUND
After the Chernobyl accident in 1986, as much as 5% of the released caesium-137 was deposited in Sweden due to a heavy rainfall 2 days after the event. A study of increased incidence of malignancies was initiated after the accident.


METHODS
The cohort included 1,137,106 inhabitants who were 0-60 years old in 1986 and lived in 8 counties of Sweden with the highest fallout of caesium-137. With the dwelling coordinate, GIS-technique and a digital map on caesium-137, each individual was matched for the exposure. Adjustments were made for several potential confounding factors. During the follow-up 33,851 malignancies was recorded 1988-1999.


RESULTS
Exposure categories were: 0-8 (reference), 9-23, 24-43, 44-66, 67-84, and > or =85 nGy/hr. The corresponding adjusted Mantel-Haenszel incidence rate ratios for total malignancies during follow-up amounted to 1.000, 0.997, 1.072, 1.114, 1.068, 1.125, respectively. The excess relative risk per 100 nGy/hr with the same adjustments and time period was 0.042 95% confidence limit 0.001;0.084. An excess for thyroid cancer or leukemia could not be ruled out.


CONCLUSIONS
Increased incidence of total malignancies possibly related to the fallout from the Chernobyl accident is seen.
Tondel
Martin
M
Department of Molecular and Clinical Medicine, Division of Occupational and Environmental Medicine, Linkoping University, Linkoping SE 581-85, Sweden. Martin.Tondel@lio.se
Lindgren
Peter
P
Hjalmarsson
Peter
P
Hardell
Lennart
L
Persson
Bodil
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002588:Cesium Radioisotopes / Q000633:toxicity*; D047852:Chernobyl Nuclear Accident; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D011847:Radioactive Fallout / Q000009:adverse effects*; D013548:Sweden / Q000453:epidemiology
D002588:Cesium Radioisotopes; D011847:Radioactive Fallout