Medical/biological study (experimental study)

Measurements of skin surface temperature during mobile phone use med./bio.

By: Anderson V, Rowley J

Published in: Bioelectromagnetics 2007; 28 (2): 159-162

Aim of study (acc. to author)

To measure temperature rises on the side of the face after 6 minutes of continuous mobile phone operation using two models of analog mobile phone system phones (operating in the 835 MHz band) and three GSM mobile phone models operating in the 900 MHz band.

Background/further details

Additionally, the temperature on the side of the face for analog mobile phone system phones while it was inoperative, transmitting, and in stand-by mode was measured in order to separate the contributions to heating from the radiofrequency amplifier and control electronics.

Endpoint

thermoregulation: skin surface temperature

Exposure

- mobile communications
- analog mobile phone
- digital mobile phone
- GSM

Exposure	Parameters
Exposure 1: 835 MHz Exposure duration: continuous for 6 min	power: 600 mW mean
Exposure 2: 900 MHz Exposure duration: continuous for 6 min	power: 250 mW mean

General information

The tests were performed on three GSM and two AMPS phone models that were in use in the mid-1990s and may not be representative of current designs or battery technologies. If the phone had an extendable antenna this was pulled out during the measurements.

Exposure 1

Main characteristics

Frequency	835 MHz
Type	electromagnetic field
Exposure duration	continuous for 6 min

Exposure setup

Exposure source	cellular phone AMPS, at full power
Chamber	The subject sat on a chair in a semi-anechoic chamber during exposure and warm-up period.
Setup	Immediately following a 15 min warm-up period, the phone in test mode transmitting at full power was held loosely with the fingers by the subject against the right hand side of his head and touched the skin in the typical use position for a period of 6 min.
Additional info	An additional comparative test was performed with one of the AMPS phones while it was inoperative, transmitting, and in stand-by mode in order to separate the contributions from the RF amplifier and control electronics.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power	600 mW	mean	-	-	-

Exposure 2

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Exposure duration	continuous for 6 min

Exposure setup

Exposure source	cellular phone GSM, at full power

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power	250 mW	mean	-	-	-

Exposed system:

human
partial body: head (right cheek)

Methods Endpoint/measurement parameters/methodology

thermoregulation: skin surface temperature (at the cheek; recording of infrared images)

Investigated system:

investigation on living organism

Investigated organ system:

Time of investigation:

before exposure
after exposure

Main outcome of study (acc. to author)

For the GSM mobile phones the highest recorded temperature rise difference was 2.3°C and for the analog mobile phone system phones it was 4.5°C. The higher differential temperature rise between the two mobile phone systems may reflect the higher maximum average operating power of analog mobile phone (600 mW) versus GSM 900 (250 mW).
Additionally, comparison of temperature changes at a consistent location on the cheek for an analog mobile phone system phone showed that it was -0.7°C for inoperative status (i.e. cooler than the left control cheek side), +2.6°C for transmitting at full power and in stand-by mode +2.0°C.

Study character:

medical/biological study
experimental study
full/main study
Brief Communication

Study funded by

not stated/no funding

Dorn H et al. (2014): Experimental investigation of possible warmth perception from a head exposure system for human provocation studies with TETRA handset-like signals
Loos N et al. (2013): Is the effect of mobile phone radiofrequency waves on human skin perfusion non-thermal?
Bortkiewicz A et al. (2012): Changes in tympanic temperature during the exposure to electromagnetic fields emitted by mobile phone
Acar GO et al. (2009): Thermal effects of mobile phones on facial nerves and surrounding soft tissue
Tahvanainen K et al. (2007): Effects of cellular phone use on ear canal temperature measured by NTC thermistors
Chen HY et al. (2006): Temperature Increase in Human Heads Due to Different Models of Cellular Phones
Straume A et al. (2005): Skin temperature increase caused by a mobile phone: A methodological infrared camera study
Paredi P et al. (2001): Local vasodilator response to mobile phones
Adair ER et al. (2001): Partial-body exposure of human volunteers to 2450 MHz pulsed or CW fields provokes similar thermoregulatory responses
Bernardi P et al. (2001): Power absorption and temperature elevations induced in the human head by a dual-band monopole-helix antenna phone
Bernardi P et al. (2000): Specific absorption rate and temperature increases in the head of a cellular-phone user
Adair ER et al. (1999): Human exposure at two radio frequencies (450 and 2450 MHz): similarities and differences in physiological response

Measurements of skin surface temperature during mobile phone use med./bio.

Aim of study (acc. to author)

Background/further details

Endpoint

Exposure

General information

Exposure 1

Main characteristics

Exposure setup

Parameters

Exposure 2

Main characteristics

Exposure setup

Parameters

Methods Endpoint/measurement parameters/methodology

Main outcome of study (acc. to author)

Study funded by

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