1. Risk Assessment of Radiation-Induced Stomach Cancer in Population of Belarus M.V.Malko Institute of Power National Academy of Sciences of Belarus, Minsk, Belarus

2. The incidence in stomach cancers in the Belarusian population are presented in the report. It is found that approximately 2,740 additional stomach cancers appeared in Belarus in 1990-2007 (95% CI from 2,020 to 3,470 cases). The number of stomach cancers registered in Belarus in this period is about 67,076 cases (64,335 expected cases). According to performed assessment the relative risk of additional or radiation-induced stomach cancers averaged for the period 1986-2001 is equal to 1.03 (95% CI from 1.04 to 1.05). The excessive absolute risk of stomach cancers, EAR, averaged for the same period is assessed as 67 cases per 10 4 PYSv (95% CI from 49 cases to 85 cases per 10 4 PYSv). The averaged excessive relative risk, ERR, is estimated equal to 1.9% per 1 mSv (95% CI from 1.4 to 2.4 % per 1 mSv) and the averaged attributive risk, AR, is estimated equal to 4.1% (95% CI from 3.0 to 5.1%).

3. Contaminated areas in Belarus with the level of caesium-137 equal to 37 kBq/m 2 (1 Ci/km 2 ) or higher (in square kilometers) OblastLevel of contamination, Bq/m 2 (Ci/m 2 ) 37–185 (1-5) 185-555 (5-15) 555-1,480 (15-40) >1,480 (>40) Brest3,800470 Vitebsk35 Gomel16,8706,7402,7601,625 Grodno1,69012 Minsk2,03048 Mogilev5,4902,9001,450525 Total29,91510,1704,2102,150

4. Deposition of the isotope 137 Cs in separate provinces of Belarus as a result of the Chernobyl accident (Assessment of M.Malko) Regions of Belarus Absolute amount of deposited 137 Cs, Bq Relative amount of deposited 137 Cs (in %) Brest 6.310 14 3.9 Vitebsk 4,310 12 0.03 Gomel 1.110 16 66.5 Grodno 2.110 14 1.3 Misk region together with the city Minsk 2.710 14 1.7 Mogilev 4.310 15 26.6 Republic of Belarus 1.610 16 100

5. By calculation of doses of the whole body irradiation all radionuclides that gave some measurable contribution to the summary exposition in 1986 were considered. They are 131 I, 132 Te, 103 Ru, 106 Ru, 140 Ba, 134 Cs and 137 Cs. The short-lived isotopes 131 I, 132 Te, 103 Ru, 106 Ru, 140 Ba and 134 Cs determined approximately 85% of the summary exposition dose in the period from 26 April 1986 to 31 August 1986. The isotope 137 Cs was taken after the accident at the Chernobyl NPP as an indicator of the radioactive contamination. Therefore, only this isotope is mentioned here and below by characterizing of radioactive contamination despite the fact that contribution of other isotopes to irradiation doses is also considered.

6. Irradiation doses of inhabitants of rural settlements situated in contaminated areas of Belarus in mSv (Assessment of M.Malko) YearContamination level, kBq/m 2 (Ci/km 2 ) 3.7 (0.1)37 (1)37-185 (1-5) 185-555 (5-15) 555-1,480 (15-40) 1,480 (40) 19860.09720.97192.8968.33923.6238.87 19870.04680.46811.3954.01611.3718.72 19880.02960.29570.88122.5377.18611.83 19890.01810.18060.53821.5494.3887.224 19900.01040.10420.31040.89382.5314.167 19910.00890.08850.26390.75972.1523.542 19920.00790.07720.23020.66281.8773.090 19930.00690.06860.20430.58831.6662.743 19940.00620.06210.18490.53241.5082.482 19950.00570.05700.16980.48901.3852.280 19960.00530.05310.15830.45561.2902.124 19970.00490.04950.14750.42471.2031.980 19980.00470.04690.13970.40211.1391.875 19990.00440.04430.13190.37991.0761.771 20000.00430.04250.12670.36471.0331.700 20010.00410.04050.12060.34720.98331.619 1986-20010.26512.6517.89922.7464.41106.0

7. Assessment (M.Malko)of irradiation doses of inhabitants of rural settlement Vysoki Barok (Krasnapolye district, Mogilev region) and Chudziany (Cherikau district, Mogilev region) YearIrradiation doses, mSv Vysoki Barok Chudziany Contamination level, kBq/m 2 (Ci/km 2 ) 2,479 (67)5,420 (146.5) 198665.1142.4 198731.468.6 198819.843.3 198912.126.5 19907.015.3 1986-1990135.4296.1

8. Comparison of average irradiation doses of inhabitants of the Belarusian, Russian and the Ukrainian rural settlements situated in areas with contamination levels in 137 Cs ranges from 555 to 1,480 kBq/m 2 (15 – 40 Ci/km 2 ) CountriesAverage doses of the whole body irradiation, mSv 19861986 – 1995 1986 – 2000 Belarus23.757.863.4 Russia2060.4 Ukraine2674

9. Numbers of the Belarusian evacuees, liquidators and resettled persons as well as their equivalent irradiation doses Group of peopleNumber of persons Average irradiation dose, mSv Collective irradiation dose, personSv Evacuated inhabitants of 30-km zone 24,725  20 495 Liquidators: including liquida- tors in 1986-1987: 1988-1989: 116,567 78,380 38,187  42.6  53.6  20 4,965 4,200 765 Resettled persons110,275  60 6,600 Evacuees, liquidators and resettled persons combined together 251567  48 12,000 Republic Belarus as a whole 10,000,000  2.3 23,000