Biological Action of Radiations

Abstract

IT has been shown previously¹ that when radiation (for example, X-rays, a-particles, neutrons) is absorbed in aqueous solutions, an indirect chemical effect is produced due to the formation of free radicals and atoms: In general, this is followed by the recombination: and by interactions of these radicals with other acceptor substances (S, S₁ S₂) present, for example: This scheme of reactions must exist also in the aqueous systems of biological subjects. From the point of view of the older 'hit' theory², reaction (3) corresponds to a single 'hit', while if, for example, one gets a successive change of the (starting) substrate (S) by 1,2 ' n interactions with, for example, OH radicals, which is equivalent to 1,2 n 'hits'. It can be shown that—under certain conditions—there is a complete formal analogy between the 'hit' theory, which is described by Poisson's formula, and the mathematical expression for the above system of equations (3, 3·1, 3·n).