Exposure to radiofrequency electromagnetic fields (RF-EMF) has rapidly increased and little is known about exposure levels in children. This study aims to describe personal RF-EMF environmental exposure levels from handheld devices and fixed site transmitters in European children and its day-to-day and year-to-year repeatability.Methods
Environmental RF-EMF exposure (µW/m2) was measured in 529 children (ages 8–18) in Denmark, the Netherlands, Slovenia, Switzerland, and Spain using personal portable exposure metres over 3 days in 2014–2016, and repeated in 28 children one year later. Metres captured exposure every 4 s. Activity diaries collected children’s location and use of mobile devices. Six general frequency bands were defined: total, digital enhanced cordless telecommunications (DECT), television and radio antennas (broadcast), mobile phones (uplink), mobile phone base stations (downlink), and WiFi. We used mixed effects models with region random effects to estimate associations between mobile device use and exposure. Day-to-day and year-to-year repeatability was calculated through Spearman correlations.Results
Median total exposure was 75.5 µW/m2. Downlink was the largest contributor to total exposure (27.2 µW/m2) followed by broadcast (9.9 µW/m2). Exposure from uplink was lower (4.7 µW/m2). WiFi and DECT contributed very little to exposure levels. Exposure was higher during day (94.2 µW/m2) than night (23.0 µW/m2), and slightly higher during weekends than weekdays, although varying across regions. Exposure was generally highest while children were travelling (171.3 µW/m2) and outside (157.0 µW/m2). Children living in urban environments had higher exposure. Older children, girls, and users of mobile phones had higher uplink exposure but not total exposure. Repeatability was high for total, downlink, and broadcast in the year-to-year repeatability (rho between 0.54 and 0.66).Conclusion
Largest contributors to total RF-EMF exposure were downlink and broadcast, which was consistent one year later. Location of home (region and urbanicity) was associated with higher exposure. More frequent mobile phone use was associated with higher uplink exposure. It is important to continue evaluating RF-EMF exposure in children as mobile devices, use habits, and technologies continue to evolve.