It is ironic that the event that gave birth to our fear of nuclear radiation, the atomic bombing of Hiroshima Japan, should also provide us with the knowledge of how little risk such radiation poses.
Given that fear of radiation gave birth to opposition to nuclear power, leading to the closure of Germany’s last three operating nuclear plants, it seems relevant to consider what the study of the atomic bomb survivors has taught us.
In the United States, many environmental groups still avow fear of radiation as the reason for their continued opposition to nuclear energy.
Ionizing/nuclear radiation is nowhere near the danger that most of us assume.
The Life Span Study has followed 86,600 survivors of Hiroshima and Nagasaki, known in Japan as the hibakusha, and their offspring, for nearly 80 years, comparing their health to Japanese citizens not exposed to the doses and types of radiation the bombs produced.
One key finding is that among those exposed to the terrifyingly highest doses, roughly 14,000 people who were within one kilometer of where the explosion took place, exposure increased the likelihood of death from cancer by less than one percent! (People exposed to those high doses had a 20 percent higher chance of dying from some types of heart disease through the period of 1950-1980.
A second key finding is that people who were exposed to lower doses — but which were still radically higher than those released by nuclear plant accidents like Chernobyl and Fukushima — suffered no increase in cancer compared to those in the unexposed group.
We fear that ionizing radiation exposure causes cancer, and since the 1930s, cancer has been the most feared disease in the industrialized world.
It’s important to note that these exposures occurred not just at the instant of the bomb blast itself but from radioactive fallout the survivors inhaled in the air and ingested in water and food for weeks.
A third key finding is that this exposure caused no multi-generational health effects.
Children born to mothers already pregnant suffered horrific birth defects, but the offspring of the hibakusha who became pregnant later had no genetically related health problems tied to radiation exposure.
These facts fly squarely in the face of the public’s deep and historic belief in the danger of this type of radiation.
Had we known this back when the Ban the Bomb and the environmental movements were starting in the 1950s, motivated by fear of radiation, likely, opposition to nuclear energy based on its supposed dangers might not have arisen.
Fear of radiation resonates with several elements of the psychology of risk perception, the instinctively affective way we figure out what to be afraid of and how afraid to be.
But that opposition, based on that fear, is now entrenched, at least among some.
It is an article of faith, an expected expression of tribal loyalty, among members of Germany’s Green Party, for example.
In the United States, many environmental groups still avow fear of radiation as the reason for their continued opposition to nuclear energy.
Modern opposition to nuclear energy is now framed in economic terms, but when governments consider whether to keep older nuclear plants up and running as part of the solution to greenhouse gas emissions, opponents trot out fear of radiation as the reason for shutting these plants down.
The persistence of this fear is understandable.
Radio-phobia, as it might be called, has been carved into public belief by 70 years of not only warnings from environmental groups but movies and music, and literature, and a frightening drumbeat of alarm from the news media that fail to report what the Life Span Study has found.
Wind and solar power are a long way from supplying all the energy we need, so when nuclear plants close they are replaced by fossil fuels, which contribute to climate change.
Further, fear of radiation resonates with several elements of the psychology of risk perception, the instinctively affective way we figure out what to be afraid of and how afraid to be.
We are more afraid of risks we can’t detect with our senses, more afraid of risks that feel like they are imposed on us — especially from sources like the industry that we don’t trust — and more afraid of risks that are man-made than natural.
Further, we fear that ionizing radiation exposure causes cancer, and since the 1930s, cancer has been the most feared disease in the industrialized world.
Many governments have recognized that the threat from climate change vastly outweighs the risk from radiation and are supporting nuclear energy as one part of a clean energy future.
All that psychological and cultural baggage inflames our fear of radiation far beyond the actual threat.
So when we decide as a society on which forms of clean energy to support in the fight against climate change — clean, as in doesn’t emit greenhouse gases — fear distorts our policy making.
It has in Germany, as well as several US states, where energy policy subsidizes wind and solar energy but not nuclear.
Unfortunately, wind and solar power are a long way from supplying all the energy we need, so when nuclear plants close they are replaced by fossil fuels, which not only contribute to climate change but add to particulate air pollution that kills millions of people around the world each year.
Resistance to nuclear continues to impede its use in some places, and the root of that resistance is fear of radiation.
Thankfully many governments have recognized that the threat from climate change vastly outweighs the risk from radiation and are supporting nuclear energy as one part of a clean energy future.
But resistance to nuclear continues to impede its use in some places, and the root of that resistance is fear of radiation.
We urgently need to respect the evidence about the minimal actual danger posed by such radiation if we are to maximize one of the tools that could help us fight climate change, perhaps the greatest risk humans have ever faced.
A version of this article first appeared on aeon.co
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David Ropeik is a retired Harvard University Instructor, consultant in risk communication, and author of “How Risky Is It, Really? Why our fears don’t always match the facts.”