Cesium 137 (L. caesius, blue sky); Cs; at. Mass 136,9070895(5); at. n° 55; m.p. 28,44°C; b.p. 671°C; sp. gr. 1,873; half-life 30,0700 years; 8,684E1 Ci/gr; β-; 0,514 MeV; range ~1560 μ. The cesium 137 have a physical half-life of 30,07 years, a biological half-life of 70 days an a effective half-life of 69,56 days. (λ physic 7,309E-10, λ biologic 1,146E-7, λ effective 1,153E-7.) Assessing the rationality of official internal dose factor. The incorporation of 1 Bq of cesium 137 conduce after 50 years to suffer (1 Bq/1,153E-7 λe) * 1-(EXP(50*31536000*-1,153E-7)) = 8,670E6 disintegrations β- and absorb 8,67E6 disintegrations * 0,514 MeV * 1,602E-13 Joule per MeV = 7,140E-7 Joule and 7,14001 Erg which dissipate, for IRCP, in a body mass of 148,75 kg... ((8,67E6 Emissions * 0,5140 MeV * 1,602E-6 Erg per MeV * 1 EBR)/(4,800E-9 Sv/Bq * 1 Bq * 100 Erg/gr * 100 Rad/Sv) = 148,75 kg) with a radius of (148750,2595 cm3/(4/3*3,14159))^(1/3) = 32,8693 cm. The particle β- which penetrate no more than 1560 μ in tissues travel in rational calculation 210,7 times far away it can physically go... (328692,43 μ/1560 μ = 210,7.) In other words the real absorbed dose is reduce 9,35 millions times. (210,70^3 = 9,35E6 or1,49E5 gr/1,59E-2 gr = 9,35E6.) This dose factor is false. iIs here for reduce the real absorbed dose. Is a serial killer dose factor. Calculating real the dose produce by one β- particle with 0,514 MeV energy and 1560 μ penetration capacity in tissues: (1 Bq * 0,5140 MeV * 1,602E-6 Erg per MeV * 1 EBR)/((4/3 * 3,14159 * (1560 * 0,0001^3)) gr * 100 Erg/gr * 100 Rad/Sv) = 5,18E-9 Sv/Bq or 5,18 nanoSievert per Becquerel. The committed dose for 1 Bq in 50 years is then (1 Bq/1,15E-7 λ effective s-1 * (1-Exp(50*365*24*60*60 * -1,15E-7 λ effective))) * 5,18E-9 Sv/Bq) = 0,0449 Sv/Bq or 44,90 milliSievert per Becquerel.
Posted on: Mon, 15 Jul 2013 11:09:38 +0000
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