Areas with 10,000 Bq/m² of radioactivity considered “highly contaminated” by study — Over 30,000 square kilometers in Japan exceed level, 8% of nation

 

OBJECTIVE: To evaluate the risk of acute childhood leukaemia in areas of Sweden contaminated after the Chernobyl reactor accident in April 1986. [...]

MAIN OUTCOME MEASURES: Risk of leukaemia in areas contaminated after the Chernobyl accident compared with the rest of Sweden and in the same areas before the accident.

RESULTS: During six and a half years of follow up after the accident the odds ratio for acute leukaemia was 0.9 in highly contaminated areas (> or = 10 kBq/m2) compared with the same areas before the accident. For the subgroup acute lymphoblastic leukaemia in children aged under 5 years at diagnosis the odds ratio was 1.5. For all cases diagnosed after May 1986 in highly contaminated areas compared with areas of low contamination the odds ratio was 0.9. For acute lymphoblastic leukaemia in children aged under 5 years at diagnosis the odds ratio was 1.2 in highly contaminated areas compared with areas of low contamination. [...]