Blood analysis in electrosensitivity (2005-2009)
P. De Boever, F. Boonen, R. Weltens & D. Ooms
Hypersensitivity to electricity : a genetic investigation
It was investigated to what extent DNA damage can detected when blood cells are exposed to electric current and electromagnetic radiation. A particular aim was to verify if electrosensitive patients could be discriminated from their controls based on the in vitro differential reaction of blood cells when exposed to electromagnetic radiation.
The project focused on the comet assay and the micronucleus assay as sensitive techniques to detect DNA damage. Blood cells of presumed electrosensitive persons did not react in a different way to electromagnetic radiation. No significant differences were found using the comet assay and the micronucleus test. It was shown that the baseline DNA damage between individuals varies substantially. The results are in agreement with the generally accepted hypothesis that electromagnetic radiation of 50 Hz does not induce direct DNA damage (strand breaks) because of the low energy content of the nonionizing radiation.
In a second stage of the project, the comet assay was optimized to allow for the detection of DNA damage caused by the oxidation of guanine to 8-oxoguanine. This new test protocol was used for detecting oxidative stress in a THP-1 monocytic cell line. The results indicate that cytotoxicity of THP-1 cells is significantly increased when the cells are treated with paraquat (to induce oxidative stress) in combination with an exposure to 50 Hz fields. This effect only occurred at high concentrations of paraquat ( 0.625 mM to 5 mM ) and intense doses of 500 µT and 1 mT. It could be confirmed with the comet assay that significantly more oxidative DNA damage occurred at non-cytotoxic test conditions ( 0.625 mM paraquat and 500 µT 50 Hz) in a combined exposure compared to treatment with paraquat or 50 Hz fields separately. Comparable experiments were done with primary cells obtained from blood of healthy volunteers. The comet assay repeatedly showed that exposure of peripheral blood mononuclear cells to 100 µT led to an increased amount of oxidative DNA damage compared to control cells. Combined exposure of 50 Hz with hydrogen peroxide and Ro 12-9786 (a fotosensitizer) was done to test the hypothesis that 50 Hz could change the reactivity of the cells. No additive effect of 50 Hz exposure was observed in the different experimental conditions that were tested.
The results of the project did not allow for a discrimination of electrosensitive patients based on a cytogenetic test. It is believed that the selected endpoint is not sensitive enough and the study cohort too small. It is also questionable if general cytogenetic tests can help to explain the problem of electrosensitivity. The results from the in vitro experiment indicate that 50 Hz may cause increased oxidative DNA damage in a monocytic cell line and primary mononuclear cells. If this DNA damage is not repaired adequately in vivo , this may lead to DNA mutations. Primary blood cells appeared to be more sensitive than a cell culture of monocytes as they already responded on a 30 min treatment with 100 µT.
The finding of increased oxidative DNA damage as measured with the comet assay has not been reported in the literature and it may trigger off research to reveal the mode of action under in vitro conditions.
L. Verschaeve, A. Maes & R. Anthonissen
Hypersensitivity to electricity: a cytogenetic laboratory investigation
During the past few years we have had the opportunity to investigate (partly in the framework of BBEMG activities) the origin of Lipoatrophia semicircularis (L.s.); this is a rare, idiopathic condition characterized by semicircular impressions of the skin, at the front and sides of both thighs. We hypothesized an "electromagnetic origin" of this new office-related "disease" (cf. Maes et al., 2003) and found evidence that individuals who are afflicted by L.s. might be "Electromagnetic hypersensitive".
This preliminary study pointed towards the comet assay as a possible tool to discriminate between electromagnetic hypersensitive and non-hypersensitive subjects. This is the aim of our present research.
This last year, first of all, we completed our previous studies with further analyses at the molecular level (microarray analysis or genotyping). In order to further investigate whether electromagnetic hypersensitive subjects are "at risk" upon exposure to electromagnetic fields we also proposed to apply the micronucleus test on EMF-exposed blood cells from alleged hypersensitive and non hypersensitive subjects. This test is considered as one of the most important genetic tests, especially when it is extended by what is now called the "cytome" assay. This method enables us to further investigate modifications in genes. However, the cytome assay is not fully validated yet and part of our work in the first year of the new BBEMG project comprised its validation, as well as the validation of an image analysis system.
Presumed hypersensitive individuals are subjected to a number of examinations and investigations at the University of Liege (see PNE team). Blood is taken in Liege for our investigations but need to be transported to Mol. The protocol for transfering blood from subjects to our laboratory was also done this last year.
Reference : Maes A., Curvers B., Verschaeve L. (2003) Lipoatrophia semicircularis: the electromagnetic hypothesis. Electromagn et. Biol. Medicine, 22, 183-193.