Gegevens

Gepubliceerd: vrijdag 13 februari 2015 10:19

Blogpost van Prof.  Dariusz Leszczynski die uitlegt dat de blootstelling bij vele experimenten tot nu toe onrealistisch laag was onder druk van industriewetenschappers (o.a. Nokia), te laag om effecten te vinden. Men kreeg pas financiering voor studies wanneer de blootstelling onrealistisch laag was (minder dan 2,0 SAR). De lokale blootstelling (SAR-waarden) in weefsels bij een reële (real life) blootstelling aan gsm-straling blijkt echter veel hoger dan theoretisch aangenomen tot nu toe.

"The general trend of exposing cells at 2.0 SAR was strongly advocated and propagated by the scientists from the telecom industry. It was a normal occurrence at the scientific meetings that whenever scientist reported biological effects at SAR over 2.0, the above mentioned industry scientists jumped up to the microphone to condemn and to discredit the results. The argument was always the same – safety standards are set at 2.0 and examining effects above it is futile. Furthermore, any study with SAR above 2.0 was suggested to be caused by thermal effect. It meant, according to these industry scientists that the obtained biological data were irrelevant.

It was the continuous and relentlessly executed peer pressure from the industry scientists that discouraged, and in the end prevented, scientists from the academia to do freely research at SAR higher than 2.0, even when the exposure chamber had cooling system.

Later on, as I gained some experience in cell phone radiation research, I considered the limitation of 2.0 SAR as not correct. In my opinion the in vivo exposures in human head models justified the use of higher SAR. (...) the distribution of radiation field was not uniform. In center of the cell culture dish the SAR was even up to 5.5 whereas at the edges of the cell culture dish it was well below 1.0.

"This means that substantial volumes of cells contained in the skin (e.g., fibroblasts and keratinocytes) and the blood (e.g., lymphocytes and leukocytes) may experience significantly higher SAR during phone calls under realistic worst-case conditions than has been tested in most of the in vitro studies carried out so far."

"Our purpose in writing this paper is to quantify discrepancies between SAR levels applied during in vitro experiments and actual SAR levels observed in vivo. In future calls for research and recommendations of funding agencies, we strongly recommend the addition of exposure levels well above 2 W/kg for experiments intended for use in the context of risk assessments."

"Our results show that exposure levels used in most in vitro studies published so far concerning possible adverse effects of exposure from GSM mobile phones are too low to be meaningful in the context of the peak local tissue exposure expected under conservative conditions during mobile phone use operating in the frequency bands 900 and 1800 MHz, in particular for cells contained in superficial tissues as skin and blood."

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In the spring of 1999, while I was still working as an Assistant Professor at the Harvard Medical School and the Massachusetts General Hospital, I took part in the planning meeting of the EU REFLEX Project. At that time I was virtually unknown in the area of cell phone radiation research and for the invitation to join REFLEX project I need to thank Bernard Veyret, whom I meet once, at the radiation meeting in Capri.

Two persons, one present and one absent from the REFLEX meeting, impacted heavily on the direction of the research executed by my group at STUK.

The present person was Mays Swicord of Motorola, who was invited by Franz Adlkofer, to be coordinator of the REFLEX project, to provide advice. It was Mays Swicord who got visibly agitated and outright dismissed my pilot results that I presented at this meeting. In his opinion it was wrong to use high SAR even if exposure system had water cooling to keep temperature of the endothelial cell culture at 37 + 0.2-0.3^oC.

The results that I presented showed dramatic changes in protein expression in human endothelial cell line EA.hy926 exposed at 10.0 SAR. Mays Swicord said, very authoritatively that what we did was wrong, even if the temperature was controlled. As a beginner in this research arena, I took M Swicord’s advice seriously and we changed our exposure conditions to ca. 2.0 SAR (as it was calculated later it was 2.3 SAR).

Our logic to use 10.0 SAR was that effects observed at low SAR, close to the safety standard of 2.0 SAR, are difficult to detect. Thus, we wanted first see what is happening at high SAR, with temperature controlled, and then scale down exposures to closer resemble safety standards.

However, it was not good explanation to Mays Swicord. He strongly advocated use of 2.0 SAR at the most. As it appears now, see the rest of the story below, we made mistake by subduing to peer pressure of Mays Swicord.

The absent person from the first REFLEX meeting was Niels Kuster, who provided dosimetry support for the project. As I learned later, it was a great pity that Niels was absent and did not counter comments from Mays Swicord.

In the autumn 1999 Niels visited my lab in Helsinki and we discussed preliminary results of my research group. Niels was excited when got to know about the significant changes in protein expression observed at exposure level of 10.0 SAR. He was clearly disappointed when got to know that we scaled-down exposure to be close to the current safety standards. Niels suggested to continue experiments at high SAR but, we already decided to follow the general trend – exposures at 2.0 SAR.

Niels was right when asked for continuation of experiments at higher SAR and we were wrong to not listen to him…

The general trend of exposing cells at 2.0 SAR was strongly advocated and propagated by the scientists from the telecom industry. It was a strong peer pressure from, among others, Mays Swicord, Joe Elder and C-K Chou of Motorola, USA, and Sakari Lang and Jafar Keshvari of Nokia, Finland, that caused lack of in vitro studies at SAR higher than 2.0. These five scientists mentioned above were the most active in exercising peer pressure.

It was a normal occurrence at the scientific meetings, and I attended really a lot of them, that whenever scientist reported biological effects at SAR over 2.0, the above mentioned industry scientists, singularly or as a group, jumped up to the microphone to condemn and to discredit the results. The argument was always the same – safety standards are set at 2.0 and examining effects above it is futile. Furthermore, any study with SAR above 2.0 was suggested to be caused by thermal effect. It meant, according to these industry scientists that the obtained biological data were irrelevant.

It was the continuous and relentlessly executed peer pressure from the industry scientists that discouraged, and in the end prevented, scientists from the academia to do freely research at SAR higher than 2.0, even when the exposure chamber had cooling system.

Later on, as I gained some experience in cell phone radiation research, I considered the limitation of 2.0 SAR as not correct. In my opinion the in vivo exposures in human head models justified the use of higher SAR. I spoke about it already in the autumn 2002.

In the spring 2002 my research group published the first study where we presented observation that cell phone radiation at average SAR of 2.3 caused activation of p38MAP kinase/Hsp27 stress response pathway in EA.hy926 cells. Our exposure equipment was not perfect and the distribution of radiation field was not uniform. In center of the cell culture dish the SAR was even up to 5.5 whereas at the edges of the cell culture dish it was well below 1.0. Summa summarum, the average SAR in our culture dished was ca. 2.3 SAR.

Then, I saw images of SAR levels and radiation distribution in human head models and I thought that our experimental setting with non-uniform SAR distribution in cell culture dish resembles the in vivo situation in human head.

I reported this idea at the meeting in London, UK, in the autumn 2002 (2002 London Subtle termal Leszczynski; see slides 4 and 29). Unfortunately, this presentation, and also presentations in several other meetings, of this idea, did not resonate among the scientists. In fact, I had relatively heated discussion in London with Nokia’s Jafar Keshvari, whom I meet there for the first time. According to him, all what I said and did was wrong. Needless to say, I strongly disagreed with Jafar then, as I disagree now, too.

Therefore, with the extreme delight I read the recent paper in Bioelectromagnetics “The Discrepancy Between Maximum In Vitro Exposure Levels and Realistic Conservative Exposure Levels of Mobile Phones Operating at 900/1800 MHz” by Gernot Schmid and Niels Kuster.

Here are few quotes from this gamechanging paper by Schmid and Kuster:

• “In the majority of published in vitro studies, the applied avgSAR_culture values chosen for RF exposure levels were on the order of 2 W/kg or less”

• “The SAR level of 2 W/kg is widely known as the basic limit for localized exposure defined by widely adopted guidelines of the International Commission for Non-Ionizing Radiation Protection [ICNIRP, 1998] and, as such, is often used by design and/or requested by funding agencies as maximum in vitro exposure level” [bold text DL]

• “Another rationale for the use of avgSAR_culture values of 2 W/kg or less is to ensure RF induced temperature increase in cell culture is below 0.1 8C that may cause thermally induced biological effects”

• “In the context of in vitro evaluations, it is rarely discussed that exposure levels occurring locally at cell layers close to the skin or at interfaces of materials with largely different dielectric constants can be significantly higher than the psSAR10g for which 2 W/kg (general public) and 10 W/kg (occupational exposure) are the widely adopted limit values for compliance with safety guidelines” [bold text DL]

• “Kuster and Schönborn [2000] have suggested that, for in vitro experiments to adequately assess health risks associated with the use of wireless communication technologies, exposure levels applied must be considerably higher or at least equal to the maximum values locally induced in vivo in a user’s tissues.” [bold text DL]

• “The reported maximum exposure levels engendered by modern mobile phones held against the ear or body may approach the psSAR10g limit of 2 W/kg, which raises the important question of whether the avgSAR_culture levels applied during in vitro experiments, particularly those with cell types found in peripheral tissues (blood cells, keratinocytes, fibroblasts, etc.), are sufficiently high enough to represent realistic maximum mobile phone exposure.”

• “In general, it can be seen clearly that peak local SAR in skin and blood is substantially higher than 2 W/kg in all cases, which is reasonable when the relatively wide depth of averaging in computation of the 10 g average”

• “For irradiation of the TLMVT with the phone model, peak local SAR values at 900 and 1800 MHz of 12.4 and 30.7 W/kg, respectively, in the main blood vessel and 7.3 and 17.1 W/kg, respectively, in the skin were obtained.” [bold text DL]

• “local SAR, particularly in superficial tissues, is substantially above 2 W/kg, even though the mobile phone model meets the psSAR10g basic restriction for compliance testing.” [bold text DL]

• “This means that substantial volumes of cells contained in the skin (e.g., fibroblasts and keratinocytes) and the blood (e.g., lymphocytes and leukocytes) may experience significantly higher SAR during phone calls under realistic worst-case conditions than has been tested in most of the in vitro studies carried out so far.”

• “Our results show that exposure levels used in most in vitro studies published so far concerning possible adverse effects of exposure from GSM mobile phones are too low to be meaningful in the context of the peak local tissue exposure expected under conservative conditions during mobile phone use operating in the frequency bands 900 and 1800 MHz, in particular for cells contained in superficial tissues as skin and blood.”

• “This limitation of in vitro studies could be overcome by including avgSAR_culture levels that extend to higher than 20 W/kg, which, however, would require additional control experiments to probe the effect of RF-induced temperature increases, that is, >0.1 8C versus effects of non-RF induced temperature increases.”

• “Our purpose in writing this paper is to quantify discrepancies between SAR levels applied during in vitro experiments and actual SAR levels observed in vivo, an issue we have raised on several occasions. We encourage all researchers working in this area to discuss these findings in future reviews. In future calls for research and recommendations of funding agencies, we strongly recommend the addition of exposure levels well above 2 W/kg for experiments intended for use in the context of risk assessments.” [bold text DL]

There seems to be a lot of experimental work that needs to be re-done. It is a pity that it took such a long time to make this issue clear. However, it is out in open now. As saying says: “better later than never”.

Article by Schmid and Kuster is The GameChanger, with a far reaching consequences and impact on the future research. At least it should be.

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