What evidence exists on the impact of anthropogenic radiofrequency electromagnetic fields on animals and plants in the environment? A systematic map

Background

Exposure to radiofrequency (RF) electromagnetic fields (EMF), particularly from telecommunications sources, is one of the most common and fastest growing anthropogenic factors on the environment. In many countries, humans are protected from harmful RF EMF exposure by safety standards that are based on guidelines by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The ICNIRP guidelines are based on knowledge of how RF EMF affects the human body, however, there are currently no recognised international guidelines to specifically protect animals and plants. Whether the ICNIRP guidelines for humans are adequate to provide protection to the environment is a subject of active debate. There is some public concern that new telecommunications technologies, like the 5G mobile phone network may affect the natural environment. This systematic map presents a searchable database of all the available evidence on whether anthropogenic RF EMF has an effect on plants and animals in the environment. The map also identifies gaps in knowledge, recommends future research and informs environmental and radiation protection authorities.

Methods

The method used was published in an a priori protocol. Searches included peer-reviewed and grey literature published in English with no time and geographic restrictions. The EMF-Portal, PubMed and Web of Science databases were searched, and the resulting articles were screened in three stages: title, abstract and full text. Studies were included with a subject population of all animals and plants, with exposures to anthropogenic RF EMF (frequency range 100 kHz–300 GHz) compared to no or lower-level exposure, and for any outcomes related to the studied populations. For each included study, metadata were extracted on key variables of interest that were used to represent the distribution of available evidence.

Review findings

The initial search, search update and supplementary searches produced 24,432 articles and of those 334 articles (237 on fauna and 97 on flora) that were relevant were included in the systematic map. The vast majority of studies were experiments conducted in a laboratory rather than observational studies of animals and plants in the natural environment. The majority of the studies investigated exposures with frequencies between 300 and 3000 MHz, and although the exposure level varied, it was mainly low and below the ICNIRP limits. Most of the animal studies investigated insects and birds, whereas grains and legumes were the most investigated plants. Reproduction, development and behaviour were the most investigated effects for animals, and germination and growth for plants. The vast majority of the studies employed poor quality methods.

Conclusion

There are distinct evidence clusters: for fauna, on insect and bird reproduction, development and behaviour; and for flora, grain and legume germination and growth that would benefit from specific systematic reviews. The systematic map also highlights the clear need for investigating the effects of RF EMF on more species and more types of effects, and for an improvement in the quality of all studies.

Keywords

Anthropogenic radiofrequency electromagnetic fields, Base stations, 5G, Broadcast towers, Radar, Telecommunication, Plants, Animals, Environment

Background

Exposure to radiofrequency (RF) electromagnetic fields (EMF), particularly from telecommunications sources, is one of the most common and fastest growing anthropogenic factors on the environment. In many countries, humans are protected from excessive RF EMF exposure by safety standards that are based on guidelines by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The ICNIRP guidelines are based on knowledge of how RF EMF affects the human body, however, there are currently no recognised international guidelines to specifically protect animals and plants. Whether the ICNIRP guidelines for humans is adequate to provide protection to the environment is a subject of active debate. This systematic map will collate all the available evidence on whether anthropogenic RF EMF has a negative effect on plants and animals in the environment. The map will also identify gaps in knowledge, recommend future research and inform environmental and radiation protection authorities.

Methods

The proposed systematic map will include peer-reviewed and grey literature published in English. The EMF—Portal, PubMed and Web of Science databases will be searched using a search string prepared by the review team and tested for comprehensiveness against a list of known relevant reviews. Once duplicates are removed, retrieved articles will be screened in three stages: title, abstract, and full text. Studies will be selected with a subject population of all plants and animals, with exposures to anthropogenic RF EMF (frequency range 100 kHz–300 GHz) compared to no or lower-level exposure, and for all outcomes related to the studied populations. Kappa statistic tests will be conducted at each stage to ensure consistency of decision-making regarding the predefined inclusion/exclusion criteria. Eligible studies will then proceed to the data extraction phase, which will extract meta-data such as bibliographic information, taxonomic information, RF EMF exposure data, outcome(s), sample size, etc. The extracted data will then be organised into a systematic map and the findings summarised by cross-tabulating key meta-data variables in heat maps, charts or other data visualization methods. The systematic map will identify gaps in knowledge, priorities for future research and potential subtopics for further analysis and/or systematic review.