THYROID-CANCER AMONG LIQUIDATORS OF THE CHERNOBYL ACCIDENT

In 1986, immediately after the Chernobyl accident, the USSR Ministry o f Health adopted a large scale programme of establishing an All-Union Distributed Registry of persons affected by radiation due to the accid ent. The registry was based at the Medical Radiological Research Centr e of the Russian Academy of Medical Sciences (MRRC RAMS). In 1992, whe n the USSR was dissolved, this registry database contained information on 659000 persons, including 284000 Chernobyl accident emergency work ers (''liquidators''). Currently, the Russian National Medical Dosimet ric Registry (RNMDR) contains data on 435276 persons, including 167862 liquidators. This paper reviews the data for 47 verified thyroid canc ers in the liquidator subgroup of the RNMDR. Analyses show that there is an excess relative risk of thyroid cancer per Gy of 5.31 (95% confi dence intervals 0.04 and 10.58) and an excess absolute risk of thyroid cancer per 10(4) person-years per Gy of 1.15 (95% confidence interval s 0.08 and 2.22).