Written by Joyce Smith, BS. Of the twenty teeth with mercury amalgam fillings, Wi-Fi exposure of 2.4 GHz for 20 minutes significantly increased (approximately doubled) the amount of mercury released from the Wi-Fi exposed group compared to the non-exposed group.

dental healthConsumption of fish and seafood is a widely accepted source of mercury contamination; 1 however, mercury released from dental amalgam fillings is an even more toxic source2. A study by Leistevuo et al 20013 demonstrated that methyl mercury, derived from seafood and fish, was shown to be three times higher in the saliva of people with amalgam fillings than those without amalgam fillings (fish consumption was identical for both groups). Research has also shown that the mercury released from dental amalgam fillings may be up to 20 times more toxic than the form of methyl mercury found in fish 4. Moreover, exposure to electromagnetic fields (EMF) such as mobile phones and magnetic resonance imaging (MRI), significantly accelerates the release of mercury in dental fillings 5. These findings were confirmed by Shahidi et in 20146, and in the same year, Kurzun et al revealed that x-rays can also increase mercury release from dental amalgam fillings 7.

The elemental mercury found in dental amalgam is toxic to our central nervous system, renal, respiratory and hematologic systems 8 and has been banned in certain European countries 9. Wireless computer networking, commonly known as Wi-Fi, is an increasingly popular networking technology for electronic devices. A great deal of public concern has arisen regarding the safety of exposure to the electromagnetic fields (EMFs) emitted from these devices that use Wi-Fi. The objective of this study was to evaluate the effect of Wi-Fi signal exposure on mercury release from amalgam fillings.

Twenty healthy premolar teeth, extracted for endodontic treatment, were given cavities that were then restored with amalgam by the same dentist and stored in saline solution for 14 days. (The mercury released from amalgam fillings decreases gradually and reaches a constant level of release by 14 days after the filling 10). Following this procedure the teeth were exposed to artificial saliva which was the equivalent of soft gum tissue. At this point there were no statistically significant differences between the teeth samples. Ten of the teeth were then exposed to Wi-Fi radiation (Wi-Fi group) of 2.4 GHz for 20 minutes while the remaining ten teeth (control group) were protected from exposure. The level of mercury release in both groups was measured and compared for statistically significant differences.

Results revealed that the mean concentration of mercury in the artificial saliva of the Wi-Fi group was approximately double that of the control group [(0.056 ± .025 mg/L) in the Wi-Fi exposed teeth compared to (0.026 ± .008 mg/L) in the non-exposed teeth (P=0.009)].

This in vitro study had some distinct advantages over in vivo studies in that it allowed researchers to control the number and surface of the fillings. A template was used and the cavities prepared by one dentist so that all cavities were the same size and all were identical class V fillings11. After restorations the surfaces of the filled cavities were not polished to allow for a greater amount of mercury release 12. In a previous in vivo study, participants were referred by their own physicians and the investigators had no control over the number and surface of the amalgam fillings 13. Also chewing, temperature effects, food contact and bacteria exposure were confounding factors that researchers were able to control.

While this study is the first to assess the Wi-Fi exposure effect on mercury release from amalgam fillings, further studies are needed to validate these findings.

Source: Paknahad, Maryam, S. M. J. Mortazavi, Shoaleh Shahidi, Ghazal Mortazavi, and Masoud Haghani. “Effect of radiofrequency radiation from Wi-Fi devices on mercury release from amalgam restorations.” Journal of Environmental Health Science and Engineering 14, no. 1 (2016): 12.

© 2016 The Author(s). Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)

Joyce Smith, BS, is a degreed laboratory technologist. She received her bachelor of arts with a major in Chemistry and a minor in Biology from  the University of Saskatchewan and her internship through the University of Saskatchewan College of Medicine and the Royal University Hospital in Saskatoon, Saskatchewan. She currently resides in Bloomingdale, IL.

Posted October 2, 2017.

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