The third generation of Apple's AirPods (aka AirPods 3) was introduced in 2021.
April 2, 2019
Second-Generation AirPods
The newly-released second generation of Apple's AirPods (aka AirPods 2) emits Bluetooth microwave radiation in the 2.402 – 2.480 GHz frequency range to communicate with a smart phone or other wireless device.
The Specific Absorption Rate (or SAR) for the right AirPod is 0.581 watts per kilogram (averaged over 1 gram). (1) The SAR for the left AirPod is 0.501 watts per kilogram. (2)
News about the potential health risks from use of wireless headsets first went viral in 2016 (see posts below). This story has gone viral again at this time for the following reasons:
- Apple announced that it is taking orders for a new version of its wireless headset, AirPods (aka AirPods 2).
- In the past year, two major studies found conclusive evidence that microwave radiation caused cancer in rats. These studies conducted by the National Toxicology Program in the U.S. and the Ramazzini Institute in Italy received worldwide media coverage.
- The proliferation of new cell towers and antennas in preparation for the deployment of 5G,fifth generation cellular technology, has stimulated many people to seek out information about the health effects from exposure to the radiation these antennas emit on a 24-7 basis in their neighborhoods.
- More people now realize we cannot trust governments to protect us from environmental toxins. Industry has too much influence over government regulatory agencies, and governments have conflicts of interest because the telecom industry pays governments substantial taxes and fees.
News Stories
Markham Heid, Medium, March 7, 2019
https://medium.com/s/the-nuance/are-airpods-and-other-bluetooth-headphones-safe-214a0449e13a
Scientists warn wireless, Bluetooth devices may carry cancer risk
Healio: Hematology/Oncology Today, March 13, 2019
http://bit.ly/BTHealio
Earpods for Cell Phones — Are There Health Risks?
Roxanne Nelson, RN, BSN, Medscape Medical News, March 15, 2019
https://www.medscape.com/viewarticle/910453
Bethania Palma, Snopes, March 28, 2019
(1) UL Verification Services, Inc. SAR Evaluation Report for Bluetooth Earbud. FCC ID: BCG-A2032. Model Name: A2032. Report Number: 12458150-S2V1. Issue Date: 3/15/2019. Fremont, CA. https://fccid.io/BCG-A2032/RF-Exposure-Info/12458150-S2V1-FCC-Report-SAR-4204549
(2) UL Verification Services, Inc. SAR Evaluation Report for Bluetooth Earbud. FCC ID: BCG-A2031. Model Name: A2031. Report Number: 12458150-S1V1. Issue Date: 3/15/2019. Fremont, CA. https://fccid.io/BCG-A2031/RF-Exposure-Info/12458150-S1V1-FCC-Report-SAR-4204479
December 13, 2016
Apple announced today that AirPods can be ordered online and will be available in stores next week. The wireless earbuds will be available in limited quantities in more than 100 countries and territories.
Apple originally planned to ship AirPods in October and has not explained the reason for the delay. The Wall Street Journal reported that the delay was due to problems with the Bluetooth wireless technology employed by this device.
Apple’s new AirPods are wireless earbuds that employ Bluetooth technology to communicate with your smart phone, laptop, or smart watch.
According to Apple, “After a simple one-tap setup, AirPods are automatically on and always connected.”
The Specific Absorption Rate (SAR) for the AirPods
The right AirPod emits Bluetooth microwave radiation in the 2.402 – 2.480 GHz frequency range to communicate with a smart phone or other wireless device. The Specific Absorption Rate (or SAR) for the right AirPod is 0.466 watts per kilogram (averaged over 1 gram). (1) The SAR for the left AirPod is 0.510 watts per kilogram. (2)
For more information about the SAR see my post on the iPhone 7.
If one uses the AirPods many hours a day, the cumulative exposure to the brain from this microwave radiation could be substantial.
According to EE Times, the left AirPod communicates with the right AirPod using a different technology, "near field magnetic induction (NFMI)."
Although there is a substantial research literature on the health risks of exposure to magnetic fields, I am not aware of any biologic research that examines NFMI. Hence, this post focuses on the risks to the brain from exposure to Bluetooth radiation.
Is Bluetooth safe?
More than 240 scientists who have published research on electromagnetic radiation safety believe that current national and international guidelines for exposure to radio frequency radiation are inadequate to protect human health (see the
In August 2022, I found only two peer-reviewed studies have examined the effects of exposure to Bluetooth radiation. The studies which employed small samples evaluated the effects of brief exposure to Bluetooth radiation on the auditory system. Given the study limitations, the absence of significant effects is not surprising. These studies do not provide the basis to argue that long-term exposure to Bluetooth radiation is safe.
Zhou N, Qin W, Zhang JJ, Wang Y, Wen JS, Lim YM. Epidemiological exploration of the impact of bluetooth headset usage on thyroid nodules using Shapley additive explanations method. Sci Rep. 2024 Jun 21;14(1):14354. doi: 10.1038/s41598-024-63653-0.AbstractWith an increasing prevalence of thyroid nodules globally, this study investigates the potential correlation between the use of Bluetooth headsets and the incidence of thyroid nodules, considering the cumulative effects of non-ionizing radiation (NIR) emitted by these devices. In this study, we analyzed 600 valid questionnaires from the WenJuanXing platform using Propensity Score Matching (PSM) and the XGBOOST model, supplemented by SHAP analysis, to assess the risk of thyroid nodules. PSM was utilized to balance baseline characteristic differences, thereby reducing bias. The XGBOOST model was then employed to predict risk factors, with model efficacy measured by the area under the Receiver Operating Characteristic (ROC) curve (AUC). SHAP analysis helped quantify and explain the impact of each feature on the prediction outcomes, identifying key risk factors. Initially, 600 valid questionnaires from the WenJuanXing platform underwent PSM processing, resulting in a matched dataset of 96 cases for modeling analysis. The AUC value of the XGBOOST model reached 0.95, demonstrating high accuracy in differentiating thyroid nodule risks. SHAP analysis revealed age and daily Bluetooth headset usage duration as the two most significant factors affecting thyroid nodule risk. Specifically, longer daily usage durations of Bluetooth headsets were strongly linked to an increased risk of developing thyroid nodules, as indicated by the SHAP analysis outcomes. Our study highlighted a significant impact relationship between prolonged Bluetooth headset use and increased thyroid nodule risk, emphasizing the importance of considering health impacts in the use of modern technology, especially for devices like Bluetooth headsets that are frequently used daily. Through precise model predictions and variable importance analysis, our research provides a scientific basis for the formulation of public health policies and personal health habit choices, suggesting that attention should be paid to the duration of Bluetooth headset use in daily life to reduce the potential risk of thyroid nodules. Future research should further investigate the biological mechanisms of this relationship and consider additional potential influencing factors to offer more comprehensive health guidance and preventive measures.
Open access paper: https://www.nature.com/articles/s41598-024-63653-0
In 1975, Allan Frey published a paper in the Annals of the New York Academy of Sciences which reported that exposure to low intensity microwave radiation could open the blood-brain barrier in rats. Moreover, pulsed radio frequency waves (like Bluetooth) were more likely to produce this effect than continuous waves. (3)
The effect of microwave radiation on the blood-brain barrier is nonlinear—it occurs with low intensity exposures but not at higher intensity exposures.
Although other published studies have failed to find the blood-brain barrier effect, these studies tended to use higher intensity exposures or employed small samples.
Recommendations
We may not be certain of the long-term risks of using Bluetooth devices, but why would anyone insert microwave-emitting devices in their ears near their brain when there are safer ways to use a cell phone?
In the past few days, numerous news stories have appeared citing industry-affiliated scientists who claim that AirPods are safe. Nonetheless, a few news reports have addressed the potential health risks from using AirPods:
(2) UL Verification Services, Inc. SAR Evaluation Report for Wireless Headset. FCC ID: BCG-A1722. Model Name: A1722. Report Number: 16U23784-S1V1. Issue Date: 8/30/2016. Fremont, CA. https://fccid.io/BCG-A1722/RF-Exposure-Info/16U23784-S1V1-FCC-SAR-Report-3118428.pdf
(3) Peer-reviewed studies which reported on the effects of brief exposure to Bluetooth radiation:
Mandalà M, Colletti V, Sacchetto L, Manganotti P, Ramat S, Marcocci A, Colletti L. Effect of Bluetooth headset and mobile phone electromagnetic fields on the human auditory nerve. Laryngoscope. 2014 Jan;124(1):255-9. http://www.ncbi.nlm.nih.gov/pubmed/23619813
(4) Peer-reviewed studies which reported opening of the blood-brain barrier from exposure to low-intensity microwave radiation:
Sirav B, Seyhan N. Effects of radiofrequency radiation exposure on blood-brain barrier permeability in male and female rats. Electromagn Biol Med. 2011 Dec;30(4):253-60. http://www.ncbi.nlm.nih.gov/pubmed/22047463
Eberhardt JL, Persson BR, Brun AE, Salford LG, Malmgren LO. Blood-brain barrier permeability and nerve cell damage in rat brain 14 and 28 days after exposure to microwaves from GSM mobile phones. Electromagn Biol Med. 2008;27(3):215-29. http://www.ncbi.nlm.nih.gov/pubmed/18821198
Belyaev IY, Koch CB, Terenius O, Roxström-Lindquist K, Malmgren LO, H Sommer W, Salford LG, Persson BR. Exposure of rat brain to 915 MHz GSM microwaves induces changes in gene expression but not double stranded DNA breaks or effects on chromatin conformation. Bioelectromagnetics. 2006 May;27(4):295-306. http://www.ncbi.nlm.nih.gov/pubmed/16511873
Salford LG, Brun AE, Eberhardt JL, Malmgren L, Persson BR. Nerve cell damage in mammalian brain after exposure to microwaves from GSM mobile phones. Environ Health Perspect. 2003 Jun;111(7):881-3; discussion A408. http://www.ncbi.nlm.nih.gov/pubmed/12782486
Leszczynski D, Joenväärä S, Reivinen J, Kuokka R. Non-thermal activation of the hsp27/p38MAPK stress pathway by mobile phone radiation in human endothelial cells: molecular mechanism for cancer- and blood-brain barrier-related effects. Differentiation. 2002 May;70(2-3):120-9. http://www.ncbi.nlm.nih.gov/pubmed/12076339
Schirmacher A, Winters S, Fischer S, Goeke J, Galla HJ, Kullnick U, Ringelstein EB, Stögbauer F. Electromagnetic fields (1.8 GHz) increase the permeability to sucrose of the blood-brain barrier in vitro. Bioelectromagnetics. 2000 Jul;21(5):338-45. http://www.ncbi.nlm.nih.gov/pubmed/10899769
Fritze K, Sommer C, Schmitz B, Mies G, Hossmann KA, Kiessling M, Wiessner C. Effect of global system for mobile communication (GSM) microwave exposure on blood-brain barrier permeability in rat. Acta Neuropathol. 1997 Nov;94(5):465-70. http://www.ncbi.nlm.nih.gov/pubmed/9386779
Salford LG, Brun A, Sturesson K, Eberhardt JL, Persson BR. Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50, and 200 Hz. Microsc Res Tech. 1994 Apr 15;27(6):535-42. http://www.ncbi.nlm.nih.gov/pubmed/8012056
Frey AH, Feld SR, Frey B. Neural function and behavior: Defining the relationship. Annals of the New York Academy of Sciences, 247: 433–439. 1975.