Will the 5G wavelengths cause cancer or not? A conclusive answer to that question is yet to be found. And it is only one unanswered question regarding the potential health effects of 5G. There is no real scientific consensus yet on how the newest generation might affect the human body. For a better understanding of the current scientific debates, we asked two scientists the same questions – the differences in their answers show how much we still have to learn and research.


Anssi Auvinen is a professor of epidemiology at the University of Tampere (Finland). He focuses on the health effects of radiation, cancer, screening, urological and neurological diseases.


Fiorella Belpoggi is the Research Director at the Italian Ramazzini Institute. The pathologist launched a ten-year research programme on the effects of electromagnetic field contamination on rats.

Interview about health

What do we know about potential health effects of 5G?

  • How do you evaluate the quality of scientific studies regarding 5G’s effects on human health?
  • AUVINEN: There are hardly any studies to justify the quality. (laughs) My overall feeling as an epidemiologist, who studies populations, is: The populations exposed to 5G are extremely few and the exposure extremely short. So, it is really hard to conclude anything or to do anything else but start observations.

    BELPOGGI: First of all, we must distinguish 5G in the three different frequencies that are proposed of which some are already in use. These different frequencies have different scientific assessments. The 700-3600 MHz are part of the same band of frequencies already in use. From 6 GHz up to 100 GHz and more, we have millimetric waves. The first part of 5G was already studied in different studies. In my interim report – I have not written the conclusion yet – I have found numerous studies regarding the first two frequencies. In particular, I was looking for carcinogenesis and reproductive developmental endpoints. On these bands of frequencies, we have good quality studies and the IARC evaluation as possible carcinogens. These studies represent situations in which biological long-term effects are observed, in particular tumours of the nervous cells, both in strong, heavy users of mobile phones (this was already known in 2011 when the radiofrequencies were classified as possible carcinogens by IARC) and on exposed experimental animals. The review of available literature for frequency already in use shows that fertility in men and in male animals is also affected by radio frequencies in terms of number of sperm, and in mobility of the sperm. This implies men are not as fertile as our grandfathers were. People will suffer not only from cancer but also from chronic diseases like infertility that could affect younger men. Therefore, one of the suggestions is to take the phone out of the pants and far away.
  • Is there a scientific consensus on the effects of 5G on human health?
  • AUVINEN: Not really, because consensus would be a shared interpretation of the evidence. But there is no evidence, so I don’t think there could be any consensus yet. What scientists agree about is that it will be ubiquitous, very hard to measure, it will not penetrate the body to the same extent as the previous generation, so it will potentially affect the outer layers of the body. That’s all we know at the moment, I think.

    BELPOGGI: We have consensus on climate change because we see it. We don’t macroscopically see the effects of radiofrequency on health, because the most part of the population is exposed and control groups are practically inexistent, so the evidence is weak, because different variables could affect health: workplace, food, air pollution and so on. So, if we don’t apply measures to contain the exposure to radiofrequency in general, and in particular to the 5G millimetric waves, in 20 or 30 years, we could observe adverse effects on humans. If we spread millimetric waves at the present state of knowledge we will jump into the dark, and this is very frustrating for scientists. We have examples of early warnings that were not taken into account. Asbestos or benzene are both good examples. But these agents are still around us – even though we had early warnings.
  • What do you think are the reasons for the lack of scientific consensus?
  • AUVINEN: We don’t know anything yet. I don’t think there can be anything besides extrapolations and opinions. There isn’t any evidence.

    BELPOGGI: The reason is somewhat related to the independence of scientific studies. Not all scientists are independent. Furthermore, scientists have to follow certain guidelines in order to make their studies considered good for risk assessment. Sometimes, technological progress is quicker than our scientific rules. Nowadays, we have rules that are not adequate to expose the low-level hazards that affect billions of people. When we started our work in the 70s, we had high doses in the factories, so we had few people exposed to high doses in a closed environment. Nowadays we are applying the same guidelines to another situation: very low doses spread all over. This is a matter of uncertainty.
  • What do we know for sure about the effects of 5G technology on human health?
  • AUVINEN: All we know is more or less physics, which is pertinent for health effects. And that is not enough.

    BELPOGGI: We have some certainties about the lower frequencies as there are epidemiological studies and experimental studies which show that glial cells are target cells; no data are available for long term effects of millimetric waves used for the 5G deployment. Additionally, we have data both in humans and animals regarding male fertility. We can control these hazards through lowering the exposure. Furthermore, if we spread millimetric waves as a technology without any knowledge on the exposure assessment, and on the outcomes in the long term, we will perform a huge experiment on 7 billion people. That is for sure.
  • Which aspects are the least well-researched?
  •  AUVINEN: (laughs) Almost everything! What I think is probably most important is observations from real people on real health outcomes under real circumstances. Of course, we can make models and calculations on biophysics – there might be an effect or not. The next step is to make observations on cells and molecules and try to make some inference to human health, but that would be still uncertain. Then the next step would be to make observations on animals and their biological systems. But the endpoints are not always equivalent to humans and typically the exposure would be much higher than it would ever occur in humans. So as an epidemiologist myself, what we would like to study is a large number of people, well-characterized exposures – some with high exposures, some with lower exposures – and then look at various health outcomes. So far, we have some biophysics and everything else is missing.
  • How can the concern that there won't be an unaffected control group for possible long-term effects be addressed?
  • AUVINEN: It’s tricky. And it’s an interesting challenge. That’s what I meant when I said the exposure assessment will be difficult. Just the fact whether or not someone is using a mobile phone will not be enough to judge whether, or to what extent, a person is exposed. So, we have to find new approaches. Imagine: If we would have maps showing where the base stations are located and if we would be able to track people's movements through their mobile phones, then we might be able to construct the exposure but not for a long period of time. We might need to follow them for a week or two to assume that would be their typical exposure levels and then we would find people that are more exposed, and others who are less exposed, and then compare the health outcomes among those. But I don’t think anybody knows at the moment how that will be best achieved.

    BELPOGGI: This is really a problem. We have to change the scientific paradigms, as I have mentioned before. The whole planet is exposed to 5G, this is very evident. Therefore, I am asking for an integrated experimental study using as few animals as possible, because animals should only be used if we have no other possibility. In one experiment we should be studying not only carcinogenesis but also reproductive/developmental diseases, neurotoxicology, immunotoxicology – all the different issues that arose in the last decade. With this approach, we want to spare animals and learn as much as possible about early and long-term effects, and their correlation.
  • What have we learnt from studying electromagnetic fields regarding the intensity and frequency of exposure?
  • AUVINEN: Well, I must say we have very little solid evidence. What has been observed very consistently is that in these extreme low-frequency fields, children with residential exposure to higher levels have leukaemia. Is this really an effect of electromagnetic fields? We don’t know for sure, but the epidemiological observations are rather consistent. And I think that is the best evidence for an effect that we have. Most evidence is against an effect. There are still major uncertainties, but there are many studies showing the same thing. For higher frequencies, I don’t think we are able to show anything for certain or with consistency. So it’s hard to say what would be the potential effect of an increasing frequency. As an epidemiologist, I am an empiricist. Some people make wild claims that theoretically it’s very obvious that it will go this or that way – but I don’t put much weight on those claims.
  • Lower radio frequencies are already around us. Is there a scientific consensus on the effects on human health?
  • AUVINEN: No, there isn’t.

    BELPOGGI: The National Toxicology Program studied 900 MHz, as it is very close to the 700 MHz we are going to have with 5G. We studied 1.8 GHz, and both Laboratories found that nerve cells are target tissues for radiofrequencies. But the frequency is not the problem, the problem is in the electromagnetic field generated by the frequency, including millimetric waves.
  • What do we know about the health effects of millimetric waves?
  • AUVINEN: They don’t penetrate very deeply. The exposures are very local. Everybody agrees that assessing exposures in people every day will be very, very challenging.

    BELPOGGI: Millimetric waves are more problematic than other used frequencies to be assessed. I receive dozens of letters every day from people writing to me that they have a 700 MHz antenna close to their children’s school, asking what will happen? Nothing more than before, I’d say, if the level of exposure is in compliance with the Italian law, where electromagnetic fields are limited to 6/Vm – which I consider to be a relatively safe level for long term exposure on the basis of the results of our study. The problem is to maintain the electromagnetic field at a level in which we haven’t observed carcinogenesis.  [4] Millimetric waves themselves cannot go very deeply into the body. They have just one centimetre more[FB5]  or less of penetration into the skin. We have to remember that in the skin there are nerve terminations, known to be target tissues for radiofrequencies. Furthermore, we don’t know what will happen when we present frequencies from 700-3600 MHz and 26 GHz together: could the electromagnetic fields generated by these different sources be under the 6 V/m level of safety? And what will happen with the continuous change in exposure due to the beamforming technology? Is it possible to appropriately assess the level of the generated electromagnetic field? Actually, with the beamforming, depending on the users, you can have different situations of exposure at any moment. This is worrying me because we have not a clear exposure assessment.
  • How can we ensure that the everyday exposure to millimetric waves is below the guideline levels?
  • BELPOGGI: To guarantee low levels of exposure the millimetric waves should be emitted by a very large number of antennas. If there is a conventional antenna very close to you, that doesn’t mean you are more exposed than people far from it. If there is a huge antenna covering a large area, it doesn’t mean you are more exposed the closer you get. That is not how it works. The fact that we have more antennas means that each of them has lower potency, they could affect us less than the distant ones. Because the distant antennas are more powerful in order to reach the users. So, it is not a question of number, but a question of energy that reaches you and will be absorbed by your body. But usually, people believe in what they see, so more antennas for the general population means more exposure. The exposure is related to the electromagnetic field generated by the emission, not by the number of antennas. The health-related problems are raised from the difficulty of exposure assessment and from the lack of information about the long term effects of the field generated by millimetric waves. Hypothetically, if we could maintain the limits of the electromagnetic fields to what we have now in Italy, the hazards would be exactly the same we have nowadays with the already used frequencies.
  • When will scientists be able to forecast actual exposures to 5G networks and their health effects?
  • AUVINEN: It’s very hard to say. If there are very obvious effects, they could be demonstrated quickly. But most likely if we are talking about similar situations as we have for ILF and RIF[9]  then it would take decades. It is impossible to show that something is completely harmless. From a scientific viewpoint, you cannot prove the negative. So even if you say there is no effect on a certain level, there could be an effect below that level. That being said, if there are effects like smoking and lung cancer, if there is a large effect on a lot of people and a common disease, we will find that out very quickly. But prediction is impossible.

    BELPOGGI: The bureaucracy is slowing down the process. The process to assess the risk of a compound is not directly from the lab to the regulators. There are many panels, conferences, discussions, that smother the data from the lab. I am very worried that the discussion on 5G will be so long that the industry cannot wait for the results. So the risk of the scientific process is not well-governed. The hazard should be governed, not ignored or likewise put into alarm.
  • From an ethical perspective: How can we pursue a technology that can potentially be harmful without being able to assess how harmful it is?
  • AUVINEN: (laughs) If we had good reasons to believe that there actually are health effects, then I think we should pursue it very cautiously. That is all I can say.

    BELPOGGI: I think we should set a compromise in the framework to produce new research starting tomorrow. We would need about five years to gather all the data, to forecast it in the right way. In these 5 years industry could deploy the 700 MHz and 3600 MHz. These two frequencies could be improved without any additional risk to the human population when the electromagnetic fields they are generating remain within the limits. We have to concentrate science to give answers to the possible hazards. Above all, we have to study devices in order to produce safer mobile phones. Additionally, if there are other kinds of technologies that could transport data without exposing to EMF our body and avoiding affecting our health, we should use and improve these technologies.
  • Imagine the exposure is too high and it would be damaging to human health: What is the exit strategy?
  • AUVINEN: We are a democratic society. There are ways to make decisions, to evaluate the benefits and harms. I don’t see 5G as something we are bound to forever. But I am a realist in the sense that we have been doing research on the health effects of mobile phones for 15 years, maybe more. And I am very convinced if we would find out now that the use of mobile phones on a daily basis doubles the risk of brain tumours. I don’t think that would affect people’s behaviour. They are used to it. It is the same thing that we see with tobacco. Given it has been around for such a long time, it cannot be banned anymore. I think this is applicable to the use of mobile phones or 5G. So it is up to democratic processes what benefits and harms people perceive.

    BELPOGGI: I am a toxicologist, so I am familiar with the problem of chemical residuals also when they are banned (as an example, atrazine). In the case of 5G, when further research could demonstrate a hazard, we just have to put the emission off – there will not be any residuals. We can stop it in one second. But it would not be ethical to perform a study on humans without adequate safety limits. Therefore, I push for more research, because this is what we, as developers, innovators, and a human-rights society, should do. I am not so worried about stopping 5G, in case we will find any problems, but from what we know now, the precautionary principle should be applied to limit the exposure at 6 V/m. In Italy we have it, this means that precautionary limits could be applied in the whole of Europe.
  • From your expertise as a scientist and based on the existing body of scientific evidence, how would you advise policy makers to implement and expand 5G in a way that’s as safe as possible for human health?
  • AUVINEN: They should be alert and make sure that research is becoming available, collect information, find out as soon as possible if there are real dangers.

    BELPOGGI: First of all, the legislators should work on having safer devices. Second, they should maintain the level we know as safe, i.e 6 V/m. And third, promote as quickly as possible research on millimetric waves combined with the other used frequencies and studying possible synergistic effects when combined with low doses of chemicals, that is just what happens to humans.
  • How significant are results from animal and cell studies for estimating the effects on human health?
  • AUVINEN: I think they can give us valuable leads. One of the problems is that we don’t know what are the diseases we should be investigating. And if those studies show it affects the nervous system or sting tumours, then we could focus our attention. So we need both: We need these experimental cell and animal studies, and we need human studies. The obvious benefits of lab studies are that you can control the circumstances, what the rats or mice eat, so you can exactly identify the effect of the exposure.

    BELPOGGI: In vitro studies, cell studies, could be good for orientation. But if we study carcinogenesis or reproduction or neurotoxicology, immunotoxicology, we need the whole organism. On the one hand, I support in vitro studies to focus on the endpoint. But on the other hand, we need to have a living organism to observe the behaviour of the different parameters and find out possible biomarkers/target organs to be then studied in humans.
  • What do you think about studies in which life-long exposure on rats was researched?
  • AUVINEN: I think they can be informative assuming that the exposures are still close enough to humans as well as the health outcomes. If we can be sure they reflect the same physiological response as in humans. But of course, the issue with high exposure levels is if it's only through electromagnetic fields or also thermally, how can we distinguish between the two things and make sure that the effect we observe is not due to overheating of the tissue?
  • Can we be certain that a response observed in animals or cell culture will be similar in humans?
  • AUVINEN: We cannot be sure. It depends on the model that you have, what is the relevance, how similar is the physiological system that you observe. There is no single answer.

    BELPOGGI: To perform animal studies you need very sophisticated design and procedures. You have to plan it very well, with a multidisciplinary approach. In our lab, we are applying an experimental model in which the animals are reproducing tumours very similar to humans per number and histotype. Rats live 3 years - that is comparable to 90 years in humans. So, in 3 years you can gather all the information. My background is in human pathology. I am fascinated by the fact that tumours are the same in rats and humans. Perhaps we are more similar to rats than to mice (laughs). So it is easier to reproduce a human situation in rats. We have a very ethical approach to animals. We maintain them up to their natural death – we are not killing them. We apply a “human-equivalent model”. Let me say that in about 50 years of activity, out of more the 200 compounds that were studied in our laboratory (founded in 1971), about 40% showed to be carcinogenic, and all, also over decades, were confirmed as such in epidemiological studies. Experimental studies on mice and rats are a very important tool for primary prevention because they are predictive. But they should be planned in a proper way, possibly in collaboration with epidemiologists and other specialists, in order to perform a proper study design and so obtain robust results.

The interview with Fiorella Belpoggi was conducted on 09. December 2020 and with Anssi Auvinen on 10. December 2020. Both answered the same questions.