In last month’s column (Herald. Oct. 6), I discussed how fear of nuclear radiation on the part of the general public was causing governments, most recently Japan and Germany, to make serious mistakes about their energy future. Both countries are encountering debilitating economic and environmental consequences as a result of their decisions to limit or abandon the use of nuclear power because of radiation phobia.
A major cause of that fear is the misleading television coverage about nuclear accidents like the Fukushima Dai-ichi Japanese nuclear power plant damaged recently by a tsunami. It showed people with Geiger counters clicking at alarming rates with the implication that the clicks indicate deadly contamination of the surrounding regions. To correct that implication, I explained in my October column that a World Health Organization team and a United Nations team independently found that residents and nuclear workers in the region adjacent to the plant received yearly doses that were not harmful to their health (Nature, May 12, 2012). Space, however, prevented a discussion of why Geiger counter clicks provide little information about actual health risks.
An article in the journal Science headlined “Radiation and Atomic Literacy for Nonscientists” (Oct. 25) describes an effort that directly addresses that issue. The Center for Math and Science Education at Black Hills State University in South Dakota is involved in a project to raise the level of radiation literacy among college and high school students who typically avoid science. Their research found that one of the main reasons for radiation fear is that nonscientists do not distinguish between radiation and radioactive material. “They think of both as something that spreads out from a source and affects other physical objects and people in the vicinity. Radiation is seen as ‘bad stuff’ like dirt or germs that contaminates things.” Thus Geiger counter clicks to TV viewers and scientifically naïve reporters are direct measures of deadly surrounding contamination.
The Black Hills project allows students to demonstrate for themselves that unlike germs, ionizing radiation is high-speed particles emitted from radioactive atomic nuclei. The particles do damage if they penetrate an object by breaking molecular bonds, but they must penetrate in sufficient amount to damage a person’s health. Three types of particles are emitted from a radioactive source – alpha, beta and gamma – and each has a different penetration power. The students learn that penetration capability is not known from simply hearing clicks from a Geiger counter.
For example, beta particles cannot penetrate clothing or skin and can be stopped by a piece of paper. The only way they can harm a person is if the particles are inhaled, and that can be prevented by wearing a paper mask. Alpha and gamma particles have greater ability to penetrate materials but differ in terms of the biological impact if penetration occurs. Roughly speaking, absorbing one rad (a measure of absorbed dose) from alpha particles has the same overall biological impact in terms of causing cancer, as 20 rad from gamma particles. These reasons are why the media’s preoccupation with Geiger counter clicks at the Fukushima plant continues to provide misleading information about the health effects on people in the regions adjacent to the plant.
Fear of atomic radiation by the general public is a major deterrent to using more nuclear power that emits no greenhouse gases to generate electricity. If society is serious about wanting those emissions reduced, then the power to produce baseline electricity that accounts for 40 to 50 percent of its use, must be carbon free, or nearly so. Nuclear power is the only proven carbon-free means to produce sufficient and consistent amounts to satisfy baseline requirements.
Talk about wind and solar power being able to fill that need as technologies becomes available to solve their dispersion and inconsistency problems is premature because such technologies are not yet even in sight.
But restricting the production of nuclear power is not the only reason why radiation phobia needs to be reduced. We live in a radioactive world with natural occurring background radiation all around us, and artificially produced ionizing radiation becoming more common. Gamma scintigraphy and X-ray computed tomography scans are essential in medicine and industry uses are proliferating. In order to live productively in this environment, the general public should understand what ionizing radiation is, and under what conditions it does or does not pose a health risk. The media and our schools have done a miserable job in conveying that type of understanding to nonscientists.
Garth Buchanan holds a doctorate in applied science and has 35 years of experience in operations research. Reach him at gbuch@frontier.net.
