Nuclear Industry Radiation Releases, Environmental Contamination and Health Consequences

The Nuclear Regulatory Commission (NRC) has promulgated a draft Generic Environmental Impact Statement for public comment which outlines their plans and assurances for the continuing ability to safely deal with spent nuclear reactor waste. Their term is “waste confidence.” These are some of my comments concerning the accuracy and credibility of that draft which I submitted during their public comment period.

Although the nuclear enterprise is only about 70 years old and the commercial nuclear power industry is only about 60 years old, there is quite an abundant history from which to draw observations and conclusions as to the risk and safety of the enterprise. We are informed by catastrophic nuclear “accidents/events,” both intended and unintended, with widespread radiological contamination of the environment, which have impacted the health, homes, property, livestock, livelihoods, and the pursuit of happiness of millions of people in scores of countries. Most of those losses were incurred by ordinary people, who happened to be in the way, and occurred almost entirely without compensation. These past actions have not shown responsibility on the part of either the nuclear industry or their governments in the conduct of this enterprise. Instead, they demonstrate a reckless disregard for ordinary citizens.

Almost every facility in the nuclear complex has experienced at one time or another, during its operation, a radiological release off-site of greater or lesser magnitude. Transport of radioactive isotopes has occurred by air, ground and water. Some radionuclides have been absorbed by plant life and concentrated in the food chain and so have contaminated food and livestock. During the atmospheric nuclear bomb testing era, some pathetic countermeasures such as the iodination of table salt and the promotion of baby formula over breast feeding were attempted to mitigate the effect of iodine-131, (a short-lived environmental and food contaminant); but the majority of contaminants were simply ignored even though they most certainly caused harm. Scores of radionuclides of varying half-lives and activities combined in hundreds of chemical compound variations are produced by nuclear fission in both bombs and reactors. Although many of these decay quickly, others persist long enough to be incorporated chemically into animal and plant tissues, through a myriad of physiological and biochemical pathways to become constituent building blocks of cells. These incorporated radioisotopes can cause mutagenic and oncogenic transformations in the host or adjacent cells. Each compound can be metabolized by a variety of anabolic and catabolic pathways with different biological outcomes. The simple-minded approach used by the NRC to estimate risk is almost entirely based on the external fluence of gamma and beta radiation, distributed uniformly over large areas, and largely ignores the multitude of specific risks due to in-situ radionuclide incorporation. Unlike other toxic biochemical reactions which require a certain minimum concentration of reactants (toxicants) or activation energy to proceed, nuclear processes emit particles or photons with sufficient energy to precipitate a chemical reaction from the decay of a single nucleus. Thus, there is no threshold concentration for nuclear induced chemical processes as there is with chemical toxins. In fact, some radionuclides such as polonium-210, which can be present in waste fuel, are lethally toxic even in the sub-microgram range. Analyses of the radioisotope composition of the waste from each kind of starting fuel mixture, while taking into account the degree of fuel burn-up and the stage in the cooling/aging process, is essential to fully evaluate the toxicity of all the different radioisotopes in the waste fuel in the event of an accidental release. The NRC assertion that spent fuel from mixed-oxide fueled reactors is “substantially the same” as that from uranium fueled reactors shows that they have ignored the isotope composition of the waste fuel in their risk estimations.

Ideally, when dealing with intact spent fuel elements shielded by water in pools or in steel and concrete casks only the fugitive gamma and X-radiation is of health significance; but we know from experience that the fuel doesn’t always remain clad and in place and that fissionable elements, fission products and activated reactor components often end up contaminating the surroundings. We also know from experience that radioactive contamination is not distributed uniformly as the NRC has assumed. The NRC classifies the risk of catastrophic accidents as “small” not because it believes that widespread radiological contamination is not a catastrophic event; but because it assumes the likelihood of such an event to be vanishingly small. Unfortunately, history shows us that this assumption is flat-out wrong. History shows that catastrophic nuclear accidents with widespread contamination, (with various combinations of land use sacrifice and large population relocations), have occurred about every 20 to 30 years. Examples include the reactor accidents at Fukushima and Chernobyl and the radiological waste accident at Kyshtym/Mayak/Techa River. Other intentional releases and contaminations, some with widespread dislocations, have occurred at Bikini, Mururoa, Eniwetok, Hanford, Nevada, Semipalatinsk, Lop Nor, Novaya Zemlya, Maralinga, Christmas and Monte Belo Islands, Sahara, etc. Serious accidents with major releases of radioactive materials off-site have occurred approximately once every decade. Some examples include: Windscale, Fermi 2 and Three Mile Island in addition to the above incidents. Accidents at a military reactor in Idaho and a research reactor in Yugoslavia, as well as several lethal and non-lethal criticality accidents like the one at Tokaimura, which usually affect only workers, happen with about the same frequency. Near misses include numerous “excursions,” an electrical fire at a Browns Ferry plant and a near perforation of the reactor vessel at a Davis-Bessie plant. All these demonstrate the extreme risks and perils of the nuclear enterprise. There is no reasonable expectation that in the future we will be any more clever or lucky than we were in the past.

Nuclear reactions are so dangerous because they are fundamentally uncontrollable. There is no off switch! Once enough purified, fissionable material is collected into a small enough space it achieves a life of it’s own. After a chain reaction has been initiated and the fuel has burned up to a certain degree it also becomes so radioactively and thermally hot that it is very difficult to handle. The reactor operator attempts to limit run-away chain-reactions using cadmium, boron and other neutron scavengers in control rods. Sometimes control fails because it depends on the physical integrity of the reactor. If the process gets outside of its design parameters, fuel assemblies and control rod channels can bulge, warp or distort in such a way as to prevent the proper insertion and operation of the control rods. This can lead to a rapid increase in the chain-reaction, a temperature excursion, further disruption of the reactor components and an eventual meltdown of the core. Even if the chain-reaction can be stopped the fuel components continue their radioactive decay and this keeps the fuel elements incredibly hot. If the cooling system fails to remove the decay heat from the rods and provide replacement water for that which evaporates, the rods can become exposed to air and can self-ignite burning the zirconium metal cladding. Zirconium is pyrophoric, i.e., will self-ignite and burn in air if the temperature becomes high enough. Uranium and plutonium metals are also pyrophoric and so will ignite and burn in air at high temperatures. Small modular reactors which can use metallic fuels are therefore fundamentally much more dangerous than the metal oxide fuels in common use today in large commercial reactors.

Fuel rods in cooling pools suffer from the same vulnerability as those in a reactor accident. Any sustained loss of electrical power could result in a loss of cooling, evaporation of the cooling water, exposure of the fuel assemblies to air, spontaneous ignition of the zirconium cladding and widespread dispersion of radioactive particles. Once contamination of the surrounding area has occurred it becomes virtually impossible to perform damage control to prevent further escalation of the event and to conduct remediation and clean-up efforts because of the high ambient radiation levels. This is particularly problematic if there are several contiguous facilities which may contaminate each other when impacted by the same event. Different radioisotopes have different volatilities and therefore different propagation characteristics in the event of a fire. The size of the particles also determines the distance they travel in the event of an accidental release. The draft report contains some serious estimated consequences for the volatile ruthenium group of radionuclides in fuel newly removed from the reactor, if it should be released by a spent fuel fire. The NRC attempts to rationalize this into a less serious event by postulating an early and complete evacuation of people after the accident. Unfortunately, history shows us that early post event evacuations are the exception rather than the rule. It seems to be human nature for nuclear managers to attempt first to cover-up the incident and only later reluctantly agree to evacuation. No mention is made in the report of how an emergency evacuation would be carried out to avoid the radioactive hot spots in the contamination plumes. In Fukushima, for example, some people were actually evacuated from an area of lower radiation level to an area of higher radiation because there was a failure to monitor the plumes and coordinate the evacuation based on the monitoring data.

Fuel rod storage under water in fuel pools also has the problem of radiolytic hydrogen generation which can react with the zirconium cladding and other metallic components to cause hydride embrittlement. This creates problems for the future handling of the rods in the dry cask systems because the fuel elements become fragile and can break during transfer or repackaging, thereby releasing their contents. It is unclear whether the embrittlement gets worse with continued aging in dry storage. The NRC states that the Fukushima disaster proves the design strength of spent fuel pools, in that all pools survived the tsunami and reactor explosions virtually intact. They do not mention the fact that these pools are now perched precariously six stories above the destroyed reactors and are almost impossible to access. Removing the spent fuel to a safer location would expose workers to high ambient, perhaps lethal, radiation levels. Photos of the pools in news reports from the site appear to show debris lying in the pools although the water level seems to be maintained. Two and a half years after the accident Tokyo Electric Power Company (TEPCO), the owner of the destroyed Fukushima plant, has only just now begun to deal with this spent fuel and the outcome is still far from certain.
Fuel tank radiation leaks can occur, sometimes unnoticed, through corrosion of the stainless steel liner caused by pool chemistry and emissions from the fuel elements, as well as micro-cracks in the concrete support structure. On-site discoveries of boric acid penetration as well as large tritium contamination outside the pool structures have been reported, which prove silent pool leakage. The problem with tritium is that it migrates relatively easily off-site with the liquid drainage from pool leaks or by evaporation as water vapor. Tritium is a strong biological toxin because it is readily incorporated into biological tissues. It doesn’t even require a chemical reaction since an organic molecule can incorporate tritium through an exchange mechanism between tritiated water and the hydrogen atoms of organic compounds by simple incubation in aqueous solution. Thus, tritium can be absorbed from the environment by both ingestion and inspiration. Once incorporated into the body, tritium is particularly dangerous because hydrogen is ubiquitous in biological tissue. Tritium decays at a high activity rate but emits a low energy electron. Low energy electrons have a high linear energy transfer to their surroundings and therefore cause maximum biological damage in a small volume of tissue. This energy deposition in a very small area of an organ results in a very high micro-dose to specific cellular and tissue components, which can lead to cancer or mutation if a cell is transformed and not cleared by the immune system. Therefore, micro-dose calculation is important for assessing the carcinogenic potential of tritium decay, in situ, and this micro-dose is much larger than what would be expected if the dose were to be distributed uniformly throughout the organ.

Other radionuclides present in spent fuel are also selectively incorporated into certain biological tissue because they mimic some essential biological elements. For example: radioactive cesium and rubidium mimic potassium and so are concentrated in the muscles where they can cause wasting disease such as polymyocytis, or contribute to autoimmune disorders like multiple sclerosis or even heart disease. Plutonium and strontium mimic calcium and so concentrate in the bones near the bone marrow which can cause leukemia and disorders of the blood forming units. Some alpha emitters in the circulatory system damage the vascular lining causing inflammation resulting in calcified arterial plaques which can cause infarcts and heart disease. Radioactive noble gases dissolve in fatty tissues and so concentrate in tissues like the brain, breast and bone marrow, causing cancers in these organs. A variety of radionuclides mimic iron and so are transported and stored in the body by transferrin and ferritin. Radio-iodine concentrates in the thyroid, but can also be incorporated into radioactive thyroxin which can damage the thyroxin receptors in the tissues. (Dioxin is so chemically toxic precisely because it disrupts this thyroxin/receptor binding site). It is not enough to say that these atoms are simply radioactive but one must also know where in the body they are concentrated and how their decay affects the adjacent tissue and its biochemistry. These pathways are so complex that it is virtually useless to attempt to predict biological risk based on the decay properties of radioisotopes themselves outside the body. Most of the NRC risk analyses are clearly done by physicists with limited knowledge of biology or biochemistry and so lack the insight of the biological disciplines. Physicists concentrate on the external radiation component of dose, in most cases, while ignoring the subtleties of the tissue doses at the molecular level. Radiation has also been shown to have other demonstrated statistical effects besides increasing cancer rates, such as depression of the normal bodily immune response mechanisms against pathogens and a non-specific life shortening in irradiated populations.

It is therefore curious that the NRC has chosen to add an internal radon dose to their estimate of NBR. This “radon” dose cannot even be generalized since it depends on so many factors such as smoking habits, house ventilation/air exchange systems and the composition of the underlying bedrock and soils. The NRC uses this approach when it suits their purpose of inflating the background dose for comparison purposes against NRC allowed exposure limits; but they ignore internal doses when they go against their otherwise optimistic risk projections. It is also curious that they add a significant dose due
to medical procedures which are clearly not “ natural” at all. In the USA, per capita expenditures for medical “care” are more than twice as high as the next highest developed country. Total radiation exposure due to medical procedures is also much higher in the USA than in other countries. Unfortunately this excess expenditure for health care and the excess radiation exposure from medical treatment does not translate into better health. The USA ranks low compared to other countries in such objective measures of health as life expectancy.

Prior to the nuclear age an estimated one person in ten died of cancer, now it is about one in four. Clearly environmental contamination with radionuclides and chemical toxins has effectively quadrupled the overall cancer rate between 1940 and 1980. The NRC “permissible” dose from man-made radiation (500 mR/yr) is about four to five times higher than the true level of external NBR. This would suggest that the cancer rate in people subjected to the NRC allowed exposure level to man-made radiation might be four to five times higher than the natural rate. Although the average exposure to man-made radiation during those same years probably did not reach the maximum level, it is still possible that the roughly four-fold increase in cancer rate during this period might be explained by the significant radioactive contamination of the environment due to nuclear bomb testing and radioactive emissions from power plants and the rest of the nuclear complex. The overall cancer rate post 1980 appeared to be leveling or decreasing slightly as the radioactive contamination of the environment, (after the cessation of atmospheric nuclear bomb tests) was slowly cleared and the latency period for radiogenic cancers had run its course. Unfortunately, the reactor accidents at Chernobyl and Fukushima, once again added a considerable new radioactive burden to the planet so I expect that cancer rates will hold steady or increase again in the near future.

One event which happened in 1953 is illustrative of the danger posed by radioactive contamination of the environment. Earlier in that year several above-ground nuclear bomb tests had been conducted at the Nevada Test Site, which dropped significant fallout on the downwind areas. Later in the year Hollywood filmed a movie called “The Conqueror,” starring John Wayne, in Snow Canyon, Utah, about 120 miles downwind from the test site. The particulate radioactive fallout from the earlier tests had mixed in with the soil in the canyon and the horses and wind machines stirred up large amounts of dust, together with fallout, during the filming of the movie. Years later it was observed that of the approximately 220 cast and crew members on the movie set more than 90 including John Wayne himself had contracted cancer. This is a cancer rate of nearly one person in two, a rate so far above the national average that it is statistically impossible to explain by chance.

Some genetic variations, the so-called inborn errors of metabolism, also confer increased sensitivity to radiation damage on certain susceptible individuals, rendering them much more vulnerable to environmental radiation than others. This means that the same amount of radiation which might be tolerated by one person might cause harm in another. One example is hemochromatosis, a genetic defect in iron metabolism associated with a greatly increased susceptibility to radiation damage. It has also been suggested that the more common heterozygous persons with this trait may also be at increased risk. Many other genetic variations including ataxia telangiectasia also increase the radiation risk in susceptible individuals. It is well known that pregnant women and children are also more sensitive to radiation damage than are adults.

In the end, the number one priority of the NRC should always be the preservation of the health of nuclear workers and the general public. The report mentions nothing in its risk assessment about susceptible genetic variants in the population or the need for increased levels of protection for pregnant women and children. This omission shows a total lack of consideration for the most vulnerable members of society, and a lack of caution in this regard could have devastating effects on the future of our nation since pregnant women and children represent our future. The NRC GEIS Draft Report is, therefore, not a true analysis of radiation health risk and is not based on the entirety of the scientific knowledge.

One Response to Nuclear Industry Radiation Releases, Environmental Contamination and Health Consequences

  1. Dennis Nelson says:

    This section on Radiation Releases and their Health and Environmental Consequences is taken in part from comments I submitted to the Nuclear Regulatory Commission upon their Request for Public Comments on a Generic Nuclear Waste Environmental Impact Statement rule-making. Those comments can be viewed in their entirety on the NRC Adams database. The online link to those comments is:
    https://www.nrc.gov/docs/ML1335/ML13351A006.pdf

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