Late cancer and noncancer risks among Chernobyl emergency workers of Russia.

The presented work summarizes data on estimated radiation risks among Chernobyl emergency workers of the Russian Federation. In 1991-1998, the excess relative risk (ERR) of death from malignant neoplasm was statistically significant: excess relative risk per 1 Gy (ERR/Gy)=2.11 with 95% confidence interval (CI) (1.31-2.92). In 1991-2001, the ERR estimation for incident solid cancers gives a positive, but statistically insignificant value: ERR/Gy=0.34 with 95% CI (-0.39; 1.22). In 1986-2003, radiation risk for leukemia incidence was investigated. During the first 10 y after the Chernobyl accident (1986-1996) the relative risk (RR) of leukemia (excluding chronic lymphocytic leukemia) was statistically significant: RR=2.2 with 95% CI (1.3-3.8) for emergency workers with doses>0.15 Gy in comparison with less exposed workers. In 1986-2000, a statistically significant dose response was observed for incident cerebrovascular diseases: ERR/Gy=0.39, 95% CI=(0.004; 0.77). For doses>0.15 Gy a statistically significant risk of cerebrovascular diseases as a function of mean daily dose was observed: ERR per 0.1 Gy d(-1)=2.17 with 95% CI=(0.64; 3.69). Different but overlapping cohorts of Russian emergency workers were used for these estimations. No adjustments were made for recognized risk factors for cerebrovascular diseases. All results should be considered as preliminary.