On likely linkage between dissociative electron attachment and biological effects produced by xenobiotics

A possible correlation between electron acceptor properties, in particular, dissociative electron attachment (DEA) and biological activity for a series of xenobiotic species (organic pollutants, polyphenolic antioxidants, and ascorbic acid) is reported. Formation and decay of temporary negative ions (TNIs) are studied using electron transmission and DEA spectroscopies. Experimental findings are assigned with the support of density functional theory calculations and are discussed in connection with the effects produced by these compounds in living cells. The basic ideas of the present study are derived from the work published in the earlier 60th of the XX century by A. Szent-Györgyi [1,2] and J. Lovelock [3]. Likely sources of electrons able to interact with xenobiotic molecules to form TNIs under cellular conditions are tentatively associated with mitochondria and cytochrome P450 enzymes. The formed TNIs are supposed to decay via the DEA mechanism producing negatively charged and neutral fragments, in analogy with those observed by DEA spectroscopy under gas-phase conditions. Electrochemical studies of reductive dehalogenation [4] and dehydrogenation [5] in solution demonstrate that TNIs can dissociate in condensed environment instead of dissipating their excess energy. Preliminary conclusions about a correlation between DEA and biochemical processes are summarized.