EMGO Institute for Health and Care Research Quality of Care Improving communication about electromagnetic fields and health: What can we learn from lay mental models of risk? Liesbeth Claassen 1 Tjabe Smid 1,2, Fred Woudenberg 3, Ann Bostrom 4, Danielle R. M. Timmermans 1 1 Department of Public and Occupational Health, VU University Medical center, Amsterdam 2 KLM Health Services, Schiphol 3 Municipal Health Service, Amsterdam 4 Evans School of Public affairs, University of Washington

What are electromagnetic fields? What do you know about elektromagnetic fields?

Exposure to EMF Do you think you can reduce exposure? In which situation is the total exposure to EMF for the portrayed figure person highest?

EMF and health Do you think EMF of mobile phones, base stations and /or power lines can affect the body? –And health? What do you know about government policy on EMF? How would you react to the placing of new EMF equipment in your own neighbourhood?

Information WHO Low-frequency electric fields Influence the human body just as they influence any other material made up of charged particles. When electric fields act on conductive materials, they influence the distribution of electric charges at their surface. They cause current to flow through the body to the ground. Low-frequency magnetic fields induce circulating currents within the human body. The strength of these currents depends on the intensity of the outside magnetic field. If sufficiently large, these currents could cause stimulation of nerves and muscles or affect other biological processes. Both electric and magnetic fields induce voltages and currents in the body but even directly beneath a high voltage transmission line, the induced currents are very small compared to thresholds for producing shock and other electrical effects.

Background With advancing technology and growing electricity demand, people’s exposure to EMF is increasing People’s understanding of EMF technology is poor There is (some) public concern about the potential danger of exposure to EMF Communication on EMF technology and risks (e.g. scientific results and governmental policy) often fails to address knowledge gaps and may unintentionally enhance concerns

Aims of the project Assess how people understand EMF technology, it risks and risk management actions Examine how this understanding is affected by information Develop guidelines for improved risk communication and educational material

Mental models approach States that accurate and clear risk communication should be aimed on what people need to know and understand to make informed decisions By comparing the expert model of risk with the lay model of risk you can identify knowledge gaps and typical non-expert beliefs –Expert model: summary of the current scientific knowledge and insights on risk, including disagreements and uncertainties –Lay model: summary of what people know and think about the risk

Research questions 1.What information is available to the general public? 2.What are the most important knowledge gaps and typical non-expert beliefs? 3.How can we reduce important knowledge gaps and address non-expert beliefs?

Study design three parts 1.Descriptive study: –Construction expert model: based on literature search and interviews with experts –Media-analysis: analysis of the available information (coverage on EMF and health in newspapers and TV over the last two years and the internet) –Construction lay model: based on interviews and online survey of the general public 2.Experimental study: –Testing effects of different information formats on knowledge and beliefs 3.Development of guidelines for communication

Results: the “expert” model Experts (n=15) agreed on most of the elements and links in the model Some disagreement concerning physiological mechanisms: –Some claimed that there was only a small heating effect of exposed tissue to RF fields at very close range –Others argued that there was an effect on biochemical processes in and between cells (e.g. transport through the cell membrane), and/or on brain activity

Results: media analyses The media did not reflect the current state of science (nor the government standpoint) but rather followed a laymen’s perspective on risk Information: –did not discuss technical aspects, exposure and regulation policy –suggested hazards without discussing specifics –featured local issues

Results: Lay mental models (interviews) -Little knowledge on EMF technology: “It is a mystery to me. You don’t see it …. Waves through the air?” -EMF is perceived as a potential danger: “I’ve read somewhere that some people have sleeping problems, there are even people who say it can cause cancer.” -But most people have no serious concerns: “When I read about it, I sometimes think “gee” but yes, I usually forget it very quick” -Little knowledge of and trust in risk management: “If they (i.e. the government) are doing anything than perhaps it is just on paper, they should enforce the rules but I wonder if that is the case”

Confirmatory questionnaire Aim: identification of important and common non expert beliefs and knowledge gaps Online survey (n=403): –Knowledge and beliefs on: Technical aspects and exposure Biological mechanisms, potential health effects Concerns Risk management Government policy

Results: confirmatory questionnaire (1) Knowledge gaps: Technical aspects of EMF and exposure –The sun is an important source of EMF: 47% correct –EMF are present in the body: 56% correct –EMF of power lines are characterized by high frequency waves (untrue) 10% correct –In which picture below, is the exposure highest? –Exposure is highest in B: 8.4% correct

Results: confirmatory questionnaire (2) Non-expert beliefs Effects on the body and health –It is proven that long term radiation by mobile phones are a danger to health (41%) –Long term exposure to EMF of base stations will lead to cell and DNA damage (28%) –Many people can feel the presence of EMF (41%) Concerns (range 1 -5; not at all, barely, a little, fairly, surely) –I worry about …

Results confirmatory questionnaire (3) Risk manageability (range 1-5) –I can influence the amount of radiation I am exposed to (M= 2.4; sd= 0.9) Knowledge about government policy –There is no policy: 37% –Instigates research: 57% –Informs about health risks:20% –Sets exposure limits:58% –Gives a say in placement equipment: 21% Trust in government on EMF (5 items, range 1-5) –The government …

Conclusions: comparison lay and expert model Lay knowledge about the technical aspects of EMF/ and determinants of exposure to EMF is very limited In contrast to experts, most lay people believe EMF carry health risks Many think that EMF have carcinogenic effects and that some people are especially sensitive to EMF Personal perceptions of EMF risk are low and people do not particularly worry about the danger of EMF Personal manageability of exposure is perceived as limited Lay people have little knowledge of/ and trusts in government policy towards EMF

Why bother?

Lessons for risk communication Educate people about exposure Communicate transparent about government policy Explain study results in lay terms

Experimental study (1) Testing effects of different information formats: Information on exposure and government policy (base stations, mobile phones, high voltage power lines) Internet panel Factorial (3 X 2) between subjects design (n= 25 in each condition) consecutive experiments

Experimental study (2) Testing effects of different information formats (aspects on which messages may vary): –Uncertainty of evidence, framing of risk (e.g. results of associations studies) –Exposure management (personal/ precautionary measures) –Origin of information/ conflicting interests

Questions and comments