Tamer A, Gündüz H, Ozyildirim S. (2009). The cardiac effects of a mobile phone positioned closest to the heart. Anadolu Kardiyol Derg. 9(5):380-4.
The effects of mobile phones on heart rate (HR), blood pressure (BP) and heart rate variability (HRV) have been evaluated in previous studies, with conflicting results. However previous studies positioned the phone in a headset or handset and only tested the ‘on’ and ‘off’ modes of the phone.
The aim of this study was to assess the effects of mobile phones (on, off, and ringing mode) and cardiac electrical activity when the phone is positioned right next to the heart.
A total of 24 healthy male volunteers were included in this study. The mobile phone was placed in a pocket suspended from the neck and hung over the left side of the chest. The phone was set to silent mode so that the participants didn’t know if it was on, off, or ringing. In the first step of the experiment, electrocardiographic (EGC) and blood pressure recordings were made without the mobile phone (baseline), and then while the phone was on, off, and ringing. In the second step of the experiment, the rhythm and blood pressure were recorded with a Holter ECG (to measure heart rate variability) for 30 minutes without the phone (baseline) and in the on position.
The mean age of participants was 32 years. In the first step, there was no significant difference in the blood pressure, heart rate and other heart functioning measurements between the different mobile phone modes. In the second step of the experiment, there was no significant difference in blood pressure, heart rate and heart rate variability parameters from baseline.
Interpretation and Limitations
This study suggests that mobile phones placed in direct proximity to the heart have no effects on heart function, regardless of whether the phone is on, off, or ringing, in healthy adult subjects. Some studies that have investigated the effects of mobile phones on heart function have found significant effects. Nonetheless, the authors’ findings are in accordance with other studies. The main limitations of this study are the small number of included subjects and that the ECGs were only interpreted by one researcher.
The authors conclude that mobile phones have no effect on heart rate, blood pressure, and cardiac electrical activity when they are positioned on the chest in close proximity to the heart in healthy volunteers.