April 2004

Failure to replicate Lai and Singh's reports of DNA damage

Drs. Lai and Singh (1995, 1996) reported that 2450 MHz microwaves induced DNA damage (single- and double-strand breaks) in the brain cells of exposed rats. Researchers from Dr Roti Roti's laboratory in Washington University, St Louis, Missouri, have published results from two recent studies that are in contrast to those by Drs. Lai and Singh.

In the first paper, Lagroye and colleagues did in vitro experiments to try to determine whether the results obtained by Lai and Singh, but not by others, could be related to a particular step in the assay the Lai and Singh used. They found no difference in the results whether or not this step was included - and no evidence of DNA damage from the radiofrequency radiation (RFR).

In the second study rats were exposed to the microwaves in the same way that Lai and Singh had done. Lagroye and colleagues examined the rats' brain cells for signs of DNA damage, using the assay described by Lai and Singh - but in an ancillary experiment they also used various modifications of this assay. Again, there was no evidence of DNA damage from the RFR, no matter which assay method was employed.

References:
Lagroye I, Hook GJ, Wettring BA, Baty JD, et al. Measurements of alkali-labile DNA damage and protein-DNA crosslinks after 2450 MHz microwave and low-dose gamma irradiation in vitro. Radiat Res 2004 (a);161:201-214.

Lagroye, Anane R, Wettring BA, Moros EG, et al. Measurements of DNA damage after acute exposure to pulsed-wave 2450 MHz microwaves in rat brain cells by two alkaline comet assay methods. Int J Radiat Biol 2004 (b);80:11-20.

Review of EEG studies

James Lin, in the latest of a series of articles in Radio Science Bulletin on radiofrequency radiation safety and health, examines the electroencephalogram (EEG) and mobile phone radiation. He reviews the basic physiology of the nervous system, discusses the various EEG patterns that can be seen, and outlines some of the studies that have been done in subjects exposed to radiofrequency radiation from cell phones. The article can be found at www.ursi.org

Reference: Lin JC. Human electroencephalograms (EEG) and mobile phone radiation. Radio Science Bulletin 2004;308:52-54.

Publication of a review of health risks of EM fields

R Habash and colleagues have published a review of the health risks of electromagnetic fields. The review is in two parts. The first deals with electric and magnetic fields, and the second with radio frequency radiation. The authors state in their summary:

" Overall, the existing evidence for a causal relationship between RFR and adverse health effects is limited. Additional research is needed to clarify possible associations between RFR and biological effects noted in some studies. Particular attention should be paid to long-term, low-level exposure to RFR".

Habash is at the McLaughlin Centre for Population Health Risk at the University of Ottawa.

Reference: Habash RWY, Brodsky LM, Leiss W, Krewski D, Repacholi M. Health risks of electromagnetic fields. Part II: Evaluation and assessment of radio frequency radiation. Crit Rev Biomed Eng 2003;31:197-254.

NRPB recommends adoption of international guidelines in UK

The National Radiation Protection Board has recommended that the UK adopt the guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) for limiting exposure to electromagnetic fields (EMFs) between 0-300 GHz. In 1993 NRPB published exposure guidelines that recommended the same limitations for those with occupational exposure to EMFs and for members of the general public. They now are recommending the two-tier system of ICNIRP, in which there are one set of guidelines for occupational exposure and a more restrictive set for the general public.

The report can be read at http://www.nrpb.org/publications/documents_of_nrpb/abstracts/absd15-2.htm