Radiation-induced leukemia risk among those aged 0-20 at the time of the Chernobyl accident: a case-control study in the Ukraine.

A case-control study was conducted to estimate the radiation-induced acute leukemia risk for the period 1987-1997 among residents aged 0-20 at the time of the Chernobyl accident in the most radioactively contaminated territories of the Ukraine (Rivno and Zhytomir regions). Data were collected on 272 leukemia cases diagnosed between 1 January 1987 and 31 December 1997. Of these, 98 cases were verified and interviewed. Verified cases were compared to 151 randomly selected controls matched by age, gender and type of settlement. The mean value of the estimated accumulated equivalent dose to the bone marrow was 4.5 mSv, and the maximum value was 101 mSv. A statistically significant increased risk of leukemia was found among males whose estimated radiation exposure was higher than 10 mSv. This association was statistically significant for acute leukemia cases that occurred in the period 1993-1997, particularly for acute lymphoblastic leukemia. A similar association was found for acute myeloid leukemia, diagnosed in the period 1987-1992. Copyright 2002 Wiley-Liss, Inc.