The most important thing about radiation

Nuke Ampel, by NeilGHamilton on Flickr

Those of you who follow me on Twitter (@millysievert) will know that a few weeks ago I asked some questions about radiation and got more of a response than I had bargained for.

It started with “Hey, I’ve heard that cancer risk increases from a dose of 100milliSieverts, is that per year or some other duration?” It ended with me backing out of the days-long conversation entirely, taking some time away from Twitter and several weeks off blogging. The more information I was given the less I understood, and it was hard not to feel that this subject (and nuclear energy itself! I don’t do shades of grey very well) was simply beyond my comprehension.

A few weeks later I feel like I’ve finally, finally, figured out something useful: it’s not that this topic was beyond my comprehension; I was just asking the wrong questions, led by a misguided belief that the most important thing about radiation is the radiation itself when it very rarely is.

Yes, for professionals working with highly radioactive substances the radiation is indisputably the most important bit. But for a layperson like me – and we outnumber those professionals significantly – the most important thing about radiation is how acceptable a risk it presents to me. I asked questions about radiation to try and work out once and for all what risk it presents without considering just how intensely personal the concept of risk is.

I have never smoked. I don’t like feeling dependent on anything, increasing my everyday expenditure or standing outside in the cold. For me, any positives of smoking are not worth the increased risk of cancer. At the same time, I rarely wear sunscreen. I have skin that doesn’t burn easily, I hate the faff of reapplication every couple of hours and, as a Brit, I’m only occasionally in enough sunlight for long enough for it to be a consideration. For me, the positives of ignoring sunscreen are worth the increased risk of cancer.

Someone who has watched a loved one die from cancer might choose differently or be disgusted by my own choices. That’s valid. “Is this risky?” is a question not actually answered by a yes or a no; the answer depends on many variables, from past experience to family obligations to current standard of health to sheer gut instinct. Emotions are an important part of risk perception and should be respected as such. A decision made by one individual in one set of circumstances is no more or less rational than a decision made by another individual in different circumstances.

I am not suggesting that there is no point at which the risk of harm is objectively unacceptably high. There is a certain level of radiation to which nuclear professionals of every industry, education and amount of experience will agree humans should not be exposed, except in an emergency situation that would drastically distort the acceptability of risk. Below that level, however, there is not a consensus among nuclear professionals across the nuclear spectrum, which causes problems when trying to communicate the risk of radiation to laypeople – as I think the well-meaning professionals on my Twitter feed unintentionally demonstrated.

I was directed to link after study after book, and most recommendations were immediately refuted by other professionals with opposing opinions. Through this, the pattern I picked up on is a tendency towards one of two schools of thought on radiation exposure: do you believe permitted radiation exposure should be ALARP, As Low As Reasonably Practicable, or AHANE, As High As Naturally Existing? To put it a different way and take it to extremes, do you lean more towards thinking that radiation should be treated as automatically harmful unless definitely proven otherwise or automatically harmless unless definitely proven otherwise?

Both views make sense and come from the best of intentions. It is indisputable that radiation negatively affects the human body, and people have a right to know whether choosing a home or a job within reach of a nuclear power plant increases the possibility they may get cancer. However, it is important to be clear about how small that increase is and how that possibility compares to other activities – such as smoking, or choosing not to apply sunscreen.

There is a certain point below which most people will assess a risk to be insignificant. There are also points at which it is undeniably significant but we take the chance anyway, such as with driving a car, giving birth or taking a sedentary job in an office. These relatively high-risk activities add such great benefits to our lives (well, maybe not the office bit…) that we don’t let the scarily high numbers of illness, injury or death associated with them deter us from taking part.

Again, this is intensely personal. But that’s the point: there is no magic number at which radiation becomes safe for everyone, because the very concept of safety is, below a certain threshold of risk, flexible and individual and subject to many variables.  Would I personally expose myself to a higher level of radiation than the evacuation limit for Fukushima? Absolutely. What if I were pregnant? Suddenly the question is more complicated. Entrusted with my baby nephew? Now I have no idea.

Wanting to keep people’s exposure to radiation as low as possible is understandable, but does not necessarily weigh up the risk of exposure against other risk factors. People have died from the events of Fukushima. Not from the accident itself, but from psychological and physical stress from forced evacuations. How much does the possibility you may die from stress increase after you are evacuated from your home and not permitted to return? How about the possibility of suffering from depression, or of existing depression being exacerbated to suicidal levels? Of vulnerable hospital patients worsening or even dying sooner than was avoidable? Should such factors be taken into account when considering how much ‘risk’ is associated with maintaining an exclusion zone after a nuclear accident?

The most important thing I have learned about radiation is that we cannot always measure the risk of exposure by numbers alone. We need to promote a more nuanced understanding of risk than “Low-level radiation is harmless!” and “Low-level radiation is harmful!” This is part of a broader risk communication strategy we need to adopt industry-wide in which we acknowledge that emotions are important and integrate that understanding into our entire range of communications.

A final note: there is a chance that you object to any of my assumptions above. I know I’m on shaky ground, hence why none of my drafts from the past three weeks have made it up here. Just remember that I gained these impressions by asking questions of people who work with and study radiation, who gave me information and advice that I have been mulling over for weeks. If I’ve come out with the wrong idea about something, start considering how such professionals and experts can better collaborate on developing and distributing clear messages to give people like me when we start asking questions that we naively believe to be simple.