Sep 15, 2019 07:35 PM
https://undark.org/article/nuclear-radiation-fear-lnt/
EXCERPT: . . . It was an example of a phenomenon that scientists and other experts have dubbed radiophobia — the fear of ionizing radiation. Every horror filmmaker worth her fake blood and monster makeup knows that nothing is more terrifying than the unseen: the creak on the stairs, the shadow on the curtains, the hint of fatal evil.
And radiation — a mysterious presence that can’t be felt by our senses — is just such a terror. This fear has become the default setting for most people — and plenty of experts argue that’s for good reason. Ionizing radiation strips electrons from atoms and molecules, converting them into ions, or charged particles. And in atoms and molecules comprising living tissue, such as DNA, it can wreak havoc. If the intensity and rate of exposure are too great, the organism sickens and can die...
[...] Crystallizing events like these have reinforced in the popular mind a technical model that today informs the regulation of nuclear radiation the world over. It’s called the “LNT” model, short for “linear no-threshold,” and it holds that at any level of radiation exposure greater than zero, there is some damage to human DNA. The higher the level, the greater the harm.
[...] To most scientists, regulators, and the public at large, this only makes sense. And yet, an increasingly vocal group of nuclear experts suggests that the LNT model and its zero-sum approach to radiation may well be doing more harm than good. Naturally occurring radiation surrounds us all the time, they point out — emanating up from the Earth itself, and raining down on us from the cosmos. And outsized fear of radiation, they say — driven largely by the LNT framing — does much more than frighten people like the mother who queried Maidment. It drives voters and governments, for example, to abandon or avoid nuclear power — even though its fossil-based alternatives pollute the air and warm the planet, arguably killing far more people each year. (Indeed, according to the World Health Organization (WHO), 4.2 million people die every year from outdoor air pollution — orders of magnitude more deaths than those attributable to all civilian nuclear accidents, and the bombings of Nagasaki and Hiroshima, combined.)
Similarly, the partial meltdown of three reactors at Japan’s Fukushima Daiichi Nuclear Power Plant in 2011 led to mass evacuations that many experts now say resulted in more deaths than the earthquake and tsunami that caused the accident. “Overestimating radiation risks using the LNT model may be more detrimental than underestimating them,” argued researchers Jeffry Siegel and James Welsh in a 2015 article in the journal Technology in Cancer Research and Treatment“as this approach has resulted in unnecessary loss of life due to traumatic forced evacuations, suicides, and unneeded abortions after the Fukushima nuclear accident.”
Are they right? Has the no-amount-is-safe approach to radiation — a paradigm that most of us consider so axiomatic that it informs both law and no shortage of fictionalized movie-house nightmares — actually made us less safe? [...] The divisions run deep: “Underlying the [existing] risk models is a large body of epidemiological and radiobiological data,” the Environmental Protection Agency opined in support of LNT in 2011. “In general, results from both lines of research are consistent with a linear, no-threshold dose (LNT) response model.” That assessment was echoed by the Congressionally chartered National Council on Radiation Protection and Measurements (NCRP) in April 2018. Reviewing more than two-dozen recent studies of the effects of low-dose radiation, the group concluded that the results added “substantial weight to the judgment on the use of the [existing] model for radiation protection.”
But Carol Marcus, a radiobiologist and nuclear medicine physician at UCLA who has recently petitioned the U.S. Nuclear Regulatory Commission (NRC) to relax some regulation of low-dose radiation exposures, disagrees. “The LNT,” she declared in her petition, “is based on hogwash.” (MORE - details)
EXCERPT: . . . It was an example of a phenomenon that scientists and other experts have dubbed radiophobia — the fear of ionizing radiation. Every horror filmmaker worth her fake blood and monster makeup knows that nothing is more terrifying than the unseen: the creak on the stairs, the shadow on the curtains, the hint of fatal evil.
And radiation — a mysterious presence that can’t be felt by our senses — is just such a terror. This fear has become the default setting for most people — and plenty of experts argue that’s for good reason. Ionizing radiation strips electrons from atoms and molecules, converting them into ions, or charged particles. And in atoms and molecules comprising living tissue, such as DNA, it can wreak havoc. If the intensity and rate of exposure are too great, the organism sickens and can die...
[...] Crystallizing events like these have reinforced in the popular mind a technical model that today informs the regulation of nuclear radiation the world over. It’s called the “LNT” model, short for “linear no-threshold,” and it holds that at any level of radiation exposure greater than zero, there is some damage to human DNA. The higher the level, the greater the harm.
[...] To most scientists, regulators, and the public at large, this only makes sense. And yet, an increasingly vocal group of nuclear experts suggests that the LNT model and its zero-sum approach to radiation may well be doing more harm than good. Naturally occurring radiation surrounds us all the time, they point out — emanating up from the Earth itself, and raining down on us from the cosmos. And outsized fear of radiation, they say — driven largely by the LNT framing — does much more than frighten people like the mother who queried Maidment. It drives voters and governments, for example, to abandon or avoid nuclear power — even though its fossil-based alternatives pollute the air and warm the planet, arguably killing far more people each year. (Indeed, according to the World Health Organization (WHO), 4.2 million people die every year from outdoor air pollution — orders of magnitude more deaths than those attributable to all civilian nuclear accidents, and the bombings of Nagasaki and Hiroshima, combined.)
Similarly, the partial meltdown of three reactors at Japan’s Fukushima Daiichi Nuclear Power Plant in 2011 led to mass evacuations that many experts now say resulted in more deaths than the earthquake and tsunami that caused the accident. “Overestimating radiation risks using the LNT model may be more detrimental than underestimating them,” argued researchers Jeffry Siegel and James Welsh in a 2015 article in the journal Technology in Cancer Research and Treatment“as this approach has resulted in unnecessary loss of life due to traumatic forced evacuations, suicides, and unneeded abortions after the Fukushima nuclear accident.”
Are they right? Has the no-amount-is-safe approach to radiation — a paradigm that most of us consider so axiomatic that it informs both law and no shortage of fictionalized movie-house nightmares — actually made us less safe? [...] The divisions run deep: “Underlying the [existing] risk models is a large body of epidemiological and radiobiological data,” the Environmental Protection Agency opined in support of LNT in 2011. “In general, results from both lines of research are consistent with a linear, no-threshold dose (LNT) response model.” That assessment was echoed by the Congressionally chartered National Council on Radiation Protection and Measurements (NCRP) in April 2018. Reviewing more than two-dozen recent studies of the effects of low-dose radiation, the group concluded that the results added “substantial weight to the judgment on the use of the [existing] model for radiation protection.”
But Carol Marcus, a radiobiologist and nuclear medicine physician at UCLA who has recently petitioned the U.S. Nuclear Regulatory Commission (NRC) to relax some regulation of low-dose radiation exposures, disagrees. “The LNT,” she declared in her petition, “is based on hogwash.” (MORE - details)
