How much of a risk are we to exposure to dangerous levels of radiation?

That’s part of what Fiona McNeill, McMaster University’s director of radiation sciences, is trying to answer with her work. The professor and researcher is part of a documentary called “RISK FACTOR” premièring Aug. 2 at 9 p.m. on TVO. McNeill is among a group of experts interviewed in the documentary by filmmaker Robert Lang, unpacking the true level of risk in various aspects of our lives and how to better assess and face those risks. The Spectator recently spoke with McNeill about her participation in the documentary and her work. Her responses have been edited for length.

Spectator: How and why did you decide to participate in “RISK FACTOR”?

Fiona McNeill: It started about two years ago, I had just come off research leave and an email came to my inbox from a researcher (for the documentary) trying to find a radiation scientist to talk about risk. I decided I would meet with them. The timing was interesting because I had been starting to think that communication in science is becoming ever more important. I had just taken over the graduate program and really wanted to introduce them to communication. I thought I could show the graduate students why it should be an obligation (to explain science to the public).

Spectator: What can you tell me about your work?

Fiona McNeill: I’m a professor at McMaster, and spend about 40 per cent of my time teaching mostly at the senior level. About half my students go into the nuclear industry and the other half the medical field (working with radiation often in cancer treatment). And then I do research. In my research I do two things: I build bio medical devices, and my other work is in collaboration with a colleague looking at low-dose radiation effects. Some classes and research is in the nuclear reactor at McMaster. (For instance) I did a study where I bought a whole bunch of tea. I looked very strange at the grocery store checkout. I came back to McMaster and brewed the tea and then (used) the reactor to work out how much fluorine is in tea. We could see from research that people in Hamilton, tea drinkers, are getting more fluoride than those who don’t. And the study confirmed, yes, there is fluorine. There is no other university in Canada where students spend time in a reactor. It produces a number of radio isotopes for medical and industrial use. The most common is the radioiodine used in prostate cancer treatment.

Spectator: How do we get exposed to radiation?

Fiona McNeill: Everybody gets exposed to radiation on a daily basis. Some of it is just contained within soil. You also get cosmic exposure because we’re spinning through space. There is a proportion of normal exposure, such as X-rays at the dentist or an X-ray for broken bones at the hospital. If there is a concern you may have cancer, radiation is often used in diagnoses: mammograms, CT scans, PET scans. So, as human beings we have been exposed to radiation all through evolution. Your exposure varies on the planet. India and Iran have a natural background of high radiation. At high altitudes (including on planes) there is less atmosphere to protect you from cosmic radiation. Fighter pilots can be exposed to more radiation. Commercial airline pilot and flight attendants tracked in a system. Astronauts are exposed to very high radiation. People are exposed to radiation a lot even if they don’t realize it. Our body has the capacity to repair that damage at a low level.

Spectator: How much is too much radiation?

Fiona McNeill: The question “When is it too much?” is one of my areas of study. We know what happens very clearly when exposed to high levels. Researchers use data from Hiroshima and Nagasaki. Obviously we’re never going to test radiation on people, so you have to use the data that’s available to you. A high dose can kill you. It affects bone marrow and the gastrointestinal tract. It’s a very unpleasant way to die. The challenge is when you look at data you have to make assumptions. We’re trying to look at some of these low-dose effects … but there is still uncertainty on the low level. Currently radiation protection is probably very conservative and perhaps costs more than it needs to. What we’re trying to do to provide more data so that you can get more certainty on what the true risk is. As you go down (from high dose to low dose) the effects are not deterministic. At a low dose it becomes more a matter of probability that something may happen. When looking at the people who survived the initial (Hiroshima and Nagasaki) bombing, there are higher cancer rates, and they did see some increases in birth defects. The way we do radiation protection is we say there is a level at which people are likely to get an increase in cancer. Scientists would say it’s not until 100 to 200 sieverts that you start to see excess cancer and some would say not until even higher levels of exposure. There is so much uncertainly. The general protection levels for people in Canada are set 100 times lower and managed even lower than that. Generally the levels are set so low that when someone gets exposure (it’s manageable). People who work with radiation have annual limits set, so if there is a slightly elevated exposure that worker would typically be removed from radiation exposure for the rest of the year. In some cases there have been bone marrow transplants to treat higher level exposures, but at certain doses that’s not possible. Fortunately accidents are extremely rare.

Spectator: What do you hope people will take away from “RISK FACTOR”?

Fiona McNeill: There are two messages. One is this whole personal exploration of risk, how do you make your own assessments of risk; there may be hazards but you can reduce your risks with different strategies. The other part of it is about how do you communicate this? How as scientists do we try and communicate. I think there is an aspect in this climate, this political climate of fake news and alternative facts. How do people find real information? Scientists need to find new ways to communicate with the public. Then explain how they came to those conclusions. We must learn to trust people with nuance and the grey area. In science it isn’t always black and white and we need to explain if something’s in a grey area why we made a decision.

*Original article online at