Scientists at the Swiss Tropical and Public Health Institute (Swiss TPH) looked at the relationship between exposure to radiofrequency electromagnetic fields (RF-EMF) from wireless communication devices and memory performance in adolescents.
The study found that cumulative RF-EMF brain exposure from mobile phone use over one year may have a negative effect on the development of figural memory performance in adolescents, confirming prior results published in 2015.
Figural memory is mainly located in the right brain hemisphere and association with RF-EMF was more pronounced in adolescents using the mobile phone on the right side of the head.
"This may suggest that indeed RF-EMF absorbed by the brain is responsible for the observed associations," said Martin Roosli, Head of Environmental Exposures and Health at Swiss TPH.
The rapid evolution of information and communication technologies (ICT) goes along with an increase in exposure to radiofrequency electromagnetic fields (RF-EMF) in our daily life.
The most relevant exposure source to the brain is the use of a mobile phone close to the head, researchers said.
Several studies have been conducted to identify potential health effects related to RF-EMF, though results have remained inconclusive.
Other aspects of wireless communication use, such as sending text messages, playing games or browsing the Internet cause only marginal RF-EMF exposure to the brain and were not associated with the development of memory performance.
"A unique feature of this study is the use of objectively collected mobile phone user data from mobile phone operators," said Roosli.
He emphasised that further research is needed to rule out the influence of other factors.
"For instance, the study results could have been affected by puberty, which affects both mobile phone use and the participant's cognitive and behavioural state," said Roosli.
"It is not yet clear how RF-EMF could potentially affect brain processes or how relevant our findings are in the long-term," said Roosli.
"Potential risks to the brain can be minimised by using headphones or the loud speaker while calling, in particular when network quality is low and the mobile phone is functioning at maximum power," he said.