Outdoor characterization of radio frequency electromagnetic fields in a Spanish birth cohort

• Spot measurements were performed in the immediate surrounds of children's dwellings.
• Mean root mean-square electric field and power density values were calculated.
• Most recorded values were far below international standard guideline limits.
• Data demonstrate spatial variability in the distribution of exposure levels.
• While adverse effects are proven, application of the precautionary principle may be appropriate.

There is considerable public concern in many countries about the possible adverse effects of exposure to non-ionizing radiation electromagnetic fields, especially in vulnerable populations such as children. The aim of this study was to characterize environmental exposure profiles within the frequency range 100 kHz–6 GHz in the immediate surrounds of the dwellings of 123 families from the INMA-Granada birth cohort in Southern Spain, using spot measurements. The arithmetic mean root mean-square electric field (ERMS) and power density (SRMS) values were, respectively, 195.79 mV/m (42.3% of data were above this mean) and 799.01 µW/m2 (30% of values were above this mean); median values were 148.80 mV/m and 285.94 µW/m2, respectively. Exposure levels below the quantification limit were assigned a value of 0.01 V/m. Incident field strength levels varied widely among different areas or towns/villages, demonstrating spatial variability in the distribution of exposure values related to the surface area population size and also among seasons. Although recorded values were well below International Commission for Non-Ionizing Radiation Protection reference levels, there is a particular need to characterize incident field strength levels in vulnerable populations (e.g., children) because of their chronic and ever-increasing exposure. The effects of incident field strength have not been fully elucidated; however, it may be appropriate to apply the precautionary principle in order to reduce exposure in susceptible groups.