Effects of magnetic fields on biochemical reactions

Jørgen Boiden Pedersen (Foredragsholder)

Aktivitet: Foredrag og mundtlige bidragForedrag og præsentationer i privat eller offentlig virksomhed

Beskrivelse

Effects of magnetic fields on biochemical reactions

 

J. Boiden Pedersen, M. J. Hansen, N.N. Lukzen, A.B. Doktorov

Department of Physics and Chemistry, University of Southern Denmark

Campusvej 55, DK-5230 Odense M, Denmark

 

 

The aim of the present work is to determine to what degree magnetic fields and especially rf-fields can influence biochemical and biological reactions and whether such effects can conceivable be hazardous to human health.

 

Our investigation is based on numerical and analytic solutions of the relevant model equations for the radical pair mechanism (RPM). The RPM is a well established mechanism for magnetic field effects on chemical reactions and it has been used to obtain detailed information on the intermediate radical pair step in such reactions. The good agreement between experimental results and accurate solutions of the model equations proves that model calculations can be used to provide reliable estimates of the effects; In most cases even more accurate than experimental measurements that may be extremely difficult to carry out. This procedure allows us to consider a large range of systems and types of reactions.

 

Our results for the influence of rf-fields, radiated from mobile phones, on biochemical reactions are divided into four different types of reactions.

 

Reactions in liquids,  where the radicals are free to diffuse apart. Such reactions show no measurable effect of the weak rf-field radiated by mobile phones.Reactions on membranes are characterized by a very slow diffusion and a reencounter probability equal to one in the absence of scavengers. These characteristics give rize to a very large effect of magnetic fields. However, there are several conditions that must be satisfied in order to have an effect of a rf-field. The frequency of the field, i.e. 900 MHz or 1800 MHz, must be in resonance with an electron spin transition. This requires that the radicals have very large hyperfine constant, much larger than the most common values. Another condition is that the lifetime of the radical pair must be long, i.e. scavenging must be slow; Such reactions are rare.Reactions of types 1 or 2 may show an enlarged effect if the reaction scheme includes chain reactions. An example is the lipid peroxidation which is described by a complicated set of reaction steps that include chain reactions. This leads to bifurcations and under some conditions the reaction explodes. We have determined the trigger point and is investigating its dependence on magnetic fields.Enzyme reactions or electron transfer reactions often involves radicals in fixed spatial positions and metal radical ions with large hyperfine constants. Such reactions have the potential to be affected by magnetic fields. The phosphorylation by ATP synthase has been been observed to have a very large isotope effect1. Our calculations2 confirm the new reaction scheme and show that a strong dependence on a static magnetic field may be expected; The effect of rf-fields from mobile phones is under investigation.

 

1A. L. Buchachenko et al, Proc. Nat. Acad. Sci.. USA, CCB, 48, (2005), 886-894.

2 A.L. Buchachenko, N.N. Lukzen, J. Boiden Pedersen, Chem. Phys. Lett., in press.

 

This work has been partially supported by a research grant from the Danish Council for Strategic Research under the program, Non-ionizing radiation, and INTAS grant No. 05-1000008-8070.

Periode12. apr. 2007
Begivenhedstitel8th Congress of European Bioelectromagnetics Association
BegivenhedstypeKonference
PlaceringBordeaux, France, Frankrig