Table 1.

Estimated annual regional brain cell loss and cell dose per gram tissue from ²¹⁰Po high energy alpha particles (5.305 MeV) in the proteins and lipids.*

Brain structure	Emissions	Estimated cell loss		Cell dosimetry Energy absorbed	Biolgical effectiveness
	Bq•y•g-1	Number	%•y-1	βGy•yr-1	mSv•y-1
Amygdale	347 828	1 043 484	16.65	295	5.90
Hippocampus	106 475	319 426	4.99	90	1.80
Temporal lobe	50 078	150 233	2.35	42	0.85 0.79a
Frontal lobe	49 545	148 635	2.32	42	0.84 0.75a
Occipital lobe	43 739	131 217	2.05	37	0.74
Parietal lobe	39 005	117 016	1.83	33	0.66
Substantia nigra	30 855	92 564	1.45	27	0.54
Locus ceruleus	6 848	20 544	0.30	6	0.12
Nucleus basalis	6 848	20 544	0.30	6	0.12

*The average person absorbs ≈450 βGy of cosmic radiation in a year. Since all ²¹⁰Po radiation is composed solely of alpha particles then a relative effective factor is 20 (1 Sv = 20 Gy) [29].

^aMomčilović et al.[2,3].