The Chernobyl Forest Fires and Levels of Radioactive Elements Spread Through Europe by the Smoke.

[NNadir]

Last edited Sun Oct 31, 2021, 06:22 AM - Edit history (1)

There are three papers I'll discuss in this post, one of which is about the always popular discussion of the Chernobyl accident that took place 35 years ago. Chernobyl is always more interesting to people than other industrial "accidents," and the associated mortality. Everyone wants to talk about Chernobyl; very few people in my experience are interested in discussing the deaths since 1986 of between 200,000,000 and 250,000,000 people from air pollution.

Of course, the air pollution deaths are not "accidents." They are the deliberate result of wishful thinking, selective attention, absolute contempt for future generations, and I argue, of Chernobyl and Fukushima, since, for example, Germany will be burning coal - and killing both people and the future - this winter because of Chernobyl.

The three papers I'll discuss are all in the same issue of the scientific journal Environmental Science and Technology, Vol 55, Issue 20, (2021), as of this writing (10/29/21), the current issue.

The first paper, the eye catching one, is this one:

Europe-Wide Atmospheric Radionuclide Dispersion by Unprecedented Wildfires in the Chernobyl Exclusion Zone, April 2020 The reference is this: Environmental Science & Technology 2021 55 (20), 13834-13848. The authorship is rather broad. I count 44 scientists from 22 European Countries, and a larger number of research institutions I didn't bother to count. The lead corresponding author is from France, a country which will be immune from dangerous natural gas shortages this winter whether the wind is blowing or not. He is: Olivier Masson − Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-Aux-Roses 92260, France. His institution's name is full of English cognates Institut de Radioprotection et de Sûreté Nucléaire translates as "The Institute of Radioprotection and Nuclear Safety."

Today - any "today" and not just the "today" I spending writing about the scientific paper covering the 2020 Chernobyl forest fires - between 16,000 and 19,000 people will die from air pollution. The most recent data from which this figure can be calculated can be found here: Global burden of 87 risk factors in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019 (Lancet Volume 396, Issue 10258, 17–23 October 2020, Pages 1223-1249). I reference this paper frequently in this space when people want to offer me an insipid lecture on either Chernobyl or Fukushima.

I can safely guarantee that 44 scientists from 22 European Countries will not write about the air pollution deaths today - any "today" - although in truth, the much broader list of scientists and countries, wrote the Lancet paper, which listed all sorts of causes of mortality, the overwhelming number on the list being more dangerous than nuclear power, even though people often say that nuclear energy is "too dangerous" and things that kill in far more vast numbers, say, for instance, eating fatty foods, are not considered "too dangerous." The same people who tell me that nuclear power is "too dangerous" imply that climate change is not "too dangerous." They imply this even though their favored fantasies about wind and solar energy have done absolutely nothing to address climate change.

During the 21st century, a century thus far associated with vast, expensive and wild enthusiasm for solar and wind energy, the rate at which the dangerous fossil fuel waste carbon dioxide has been rising in the planetary atmosphere, has risen from 1.52 ppm per year (the end of October 2000) and 2.54 ppm per year (the end of October 2021). I get these figures from a spreadsheet of records of carbon dioxide at the NOAA Mauna Loa carbon dioxide observatory that I have maintained for many years. They express a 12 month running average of the weekly figures for carbon dioxide concentrations and comparison with the figures recorded ten years previous.
(The observatory makes this comparison when releasing the weekly average figures: Weekly average CO2 at Mauna Loa. The annual trough for these concentrations, which usually occurs in September appears to have been reached was recorded in the week beginning September 12, 2021, when the reading was 413.09 ppm. The annual maximum, usually observed in April, was observed in the week beginning April 25, 2021, when the reading was 420.01 ppm. This is the first reading ever to exceed 420 ppm. The same week ten years previous to that week was 393.41 ppm. The first reading to exceed 400 ppm was observed for the week beginning March 16, 2014, less than ten years ago.

All of this enthusiasm for solar and wind didn't address climate change. It isn't addressing climate change. It won't address climate change. I would thus argue that this enthusiasm for solar and wind as tools to address climate change is "too dangerous." It hasn't worked. It isn't working. It won't work. The deluded enthusiasm has made things become worse faster than they were before the enthusiasm was translated into action, ineffective action.

Before discussing the exciting paper on forest fires in the Chernobyl Exclusion Zone, which is now sort of a nature preserve, albeit a radioactive exclusion zone, as a consequence of the radiation preventing it from being overly trammeled by human beings, let me introduce the two other papers I'd like to discuss which are arguably related to the Chernobyl event. They are these:

Air Quality Data Approach for Defining Wildfire Influence: Impacts on PM2.5, NO2, CO, and O3 in Western Canadian Cities (Stephanie R. Schneider, Kristyn Lee, Guadalupe Santos, and Jonathan P. D. Abbatt Environmental Science & Technology 2021 55 (20), 13709-13717)

Hydroxyl Radical Production by Air Pollutants in Epithelial Lining Fluid Governed by Interconversion and Scavenging of Reactive Oxygen Species (Steven Lelieveld, Jake Wilson, Eleni Dovrou, Ashmi Mishra, Pascale S. J. Lakey, Manabu Shiraiwa, Ulrich Pöschl, and Thomas Berkemeier Environmental Science & Technology 2021 55 (20), 14069-14079)

Let's start with the last paper, which is a paper outlining the mechanism by which air pollutants kill people, the paper on reactive oxygen species. Radical chemistry - which is often associated by the way with radiation, and is part of the mechanism by which sunbathing causes melanoma - is in the best case associated with cell death; in the worst case, as in Melanoma, it is a cause of cancer.

This is one of the important mechanisms by which air pollution kills people, but it is not the only one. The other is associated with placing additional strain on hearts.

From the introduction to the text:

Ambient air pollution is responsible for 4–9 million excess deaths per year. (1−3) Air pollutants can cause and exacerbate ischemic heart disease (e.g., myocardial infarction), cerebrovascular disease (e.g., stroke), lower respiratory infections (e.g., pneumonia), and chronic obstructive pulmonary disease (COPD). (4−6) The air pollutants that most strongly correlate with negative health outcomes are nitrogen dioxide (NO2), ozone (O3), and fine particulate matter with a diameter less than 2.5 μm (PM2.5), with the latter likely contributing more than 80% to the total excess mortality. (7,8)

PM2.5 is a complex mixture that can encompass thousands of different chemical constituents, each having distinct properties. PM2.5 originates from both natural and anthropogenic sources, including mineral dust from deserts, gasoline and diesel motor exhausts, tire and brake wear, power generation, residential energy use, agriculture, biomass burning, cooking, and cigarette smoking. Because of the great heterogeneity in both PM2.5 composition and sources, targeted PM2.5 pollution control is challenging, and, to date, there is no clear connection between one particular PM2.5 constituent and mortality estimates. (9−12) In spite of fundamental challenges studying causal relationships between air pollutants and health outcomes, it has been generally accepted that the underlying pathology of air pollutant exposure includes oxidative stress and systemic inflammation. (7,13−15) Moreover, in recent years, the oxidative potential of PM2.5 has become a common metric for measuring PM2.5 toxicity. (13,16−19) The oxidative potential of PM2.5 has been shown to vary greatly among sampling sites and proximity to the emitting source. (16,20−22) Based on case-crossover studies, it has been suggested that the risk of respiratory illness and myocardial infarction was increased in exposure episodes with high PM2.5 oxidative potential. (13,23)...

Reference 3 is the Lancet paper is routinely use to describe how many people have been dying each year from dangerous fossil fuel use since the Chernobyl reactor blew up in 1986, producing a risk that is far more interesting than more than 200,000,000 deaths from air pollution, a death toll three to four times greater than World War II, which is also more interesting than air pollution.

This paper focuses on air pollution deaths from particulates.

A little more from the introductory text:

PM2.5 contains redox-active components, most notably copper, iron, secondary organic aerosols (SOA), and quinones, which trigger the formation of reactive oxygen species (ROS) in the epithelial lining fluid (ELF) of the respiratory tract. (14,24−28) The umbrella term “ROS” encompasses several highly reactive molecules, including hydrogen peroxide (H2O2), the hydroperoxyl radical (HO2), the superoxide radical anion (O2–), and the hydroxyl radical (OH). (29) Their reactivity and stability vary greatly, with H2O2 being the most stable, and OH the most reactive. (30) ROS may induce oxidative stress and inflammation in the ELF, thereby causing adverse health effects. (14,24,31−33)

NO2 is an irritant gas that has been linked to mortality in epidemiological studies. (34,35) However, because NO2 is often co-emitted with PM2.5 and other pollutants in combustion processes, it remains unclear if it poses an independent health risk. (36,37) In the ELF, NO2 can consume antioxidants and form nitrite (NO2–) in the process. (38,39) The oxidized forms of antioxidants are typically nontoxic, but their reactive intermediates have been suggested to form ROS in small yields in the case of the glutathiyl radical. (39,40)

"ELF" is defined in the abstract of the paper as "Epithelial lining fluid," which occurs in the lungs and in other places.

I find these comments about NO2 interesting. To my knowledge - which is limited - a possible mechanism for carcinogenesis associated with NO2 is the formation of nitrous acid. The known epidemiological associative risk of air pollution and lung cancer to my mind may be tied to the formation from lysine side chains, which terminate with an amino group, suggests the possibility of the formation of nitrosamines, which are well known in the mechanism by which cigarettes cause cancer, since nitrosamines can decompose to give strong alkylating agents which alkylate DNA guanine residues, leading to cancer. Lysine is an important amino acid found in lung tissue, since the amino group is involved in carbon dioxide transport. Probably this has been discussed somewhere, I should look.

Sorry for the aside musing.

After discussing other pollutants like ozone, the authors rely on a model called "KM-SUB-ELF" to trace the carcinogenic reactive oxygen mechanism detailing one way dangerous fossil fuels kill people, not that this is as interesting as Chernobyl's explosion 35 years ago. "KM-SUB-ELF" refers to the kinetic multi-layer model of surface and bulk chemistry of epithelial lining fluid.

Well, let's not spend too much time on this; let's work our way to getting to those far more interesting fires in the Chernobyl Exclusion Zone, a nature preserve formed by the fact that humans are scared, generally, to go there, although there is a scientific/tourist element of humans who do visit the region.

Here's a few dull pictures from the ELF paper just discussed, before we go, not that the relation between air pollution and lung cancer is interesting:



The caption:

Figure 1. (a) Total ROS concentration, C∑ROS, and (b) cumulative production of ROS, N∑ROS, in the ELF as a function of ambient PM2.5 concentration after a 2 h period of pollutant exposure. The right axis in (b) shows the cumulative ROS production rate (N’∑ROS, Table S4). The solid lines represent a standard PM2.5 composition based on median mass fractions of redox-active constituents of 0.03% copper, 0.8% iron, 0.002% quinones, and 33% SOA. Markers represent explicit PM2.5 composition field data for the indicated redox-active constituents (Tables S5–S7) to illustrate the sensitivity and variance induced by the PM2.5 constituents. Shadings indicate a dynamic range of each concentration metric as a function of PM2.5 composition and concentration of gaseous pollutants.

The caption:

Figure 2. (a) Individual ROS concentrations, C, and (b) gross chemical production, P, of individual ROS in the ELF as a function of ambient PM2.5 concentration. The right axis in (b) shows the gross chemical production rate of individual ROS (P′, Table S4). The solid lines represent a standard PM2.5 composition, and the markers represent explicit PM2.5 compositions derived from field data (Tables S5–S7). CO2− and CHO2 in (a) are calculated using acid–base equilibria, as detailed in the Supporting Information, Section S6. In (b), PO2− also includes PHO2. The dotted line in (a) shows the steady-state O3 concentration in the ELF.

The caption:

Figure 4. Relative contributions of pollutants, enzymes, and antioxidants to chemical production, scavenging, and conversion of ROS in ELF for three characteristic pollution scenarios (clean, urban, megacity; see the Methods section): (a) ROS production, (b) ROS scavenging, (c) ROS net production, (d) O2–-to-H2O2 conversion, and (e) H2O2-to-OH conversion. Concentrations of individual PM2.5 constituents are determined based on a standard PM2.5 composition obtained from field observations (Tables S5–S7).

The caption:

Figure 5. (a) Production, interconversion, and scavenging of reactive oxygen species (ROS) by air pollutants and endogenous molecules in the epithelial lining fluid (ELF). Organic and inorganic constituents of fine particulate matter (PM2.5) can produce, convert, and scavenge ROS. Enzymes (catalase; superoxide dismutase, SOD) intercept ROS through the disproportionation of O2– and the decomposition of H2O2 (green). Antioxidants (ascorbate; glutathione, GSH; uric acid, UA; α-tocopherol, α-Toc) intercept OH, O2–, and H2O2, but the reaction of antioxidants and surfactant lipids with NO2 and O3 can also produce ROS (yellow). Note that PM2.5 constituents are able to convert the relatively stable reservoir species H2O2 into the highly reactive OH radical, which may cause oxidative stress (distress) and physiological damage. (30,79) (b) Schematic summary of the main reaction pathways.

I'll refer very briefly to the paper on Canadian wildfires and the pollutants they produce. In this paper, they are trying to distinguish from the "normal" air pollutants in cities that kill people and whether the same pollutants discussed in the uninteresting paper on ELF and reactive oxygen species, effect the these levels. It is, apparently, a mixed bag, depending on whether the wind blows, just like pollution associated with electricity in California and Germany depends on whether the wind blows, but the output of these pollutants is well known from forest fires.

The introductory text:

As the climate changes, it is recognized that extreme wildfire burning events will occur more frequently over larger areas. (1,2) The increase in frequency and size of wildfires has already led to negative environmental and economic effects. For example, the 2016 Horse River fire in Alberta, Canada, burned an area of 590 000 hectares in northeast Alberta. (3) The natural disaster, Canada’s costliest to date, resulted in over $3.5 billion in insurance claims and in the evacuation of 88 000 people from the city of Fort McMurray. (4) Anthropogenic climate forcing effects are estimated to have increased the likelihood of extreme wildfire events in the region by 1.5–6 times relative to natural climate forcing alone. (5)

In addition to economic and environmental impacts, wildfires can also affect air quality, as occurred from the Horse River fire. (3) Primary pollutants emitted by wildfires include greenhouse gases, such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). (6,7) Also widely studied are emissions of particulate matter, particularly PM2.5 (defined as particulate matter less than 2.5 μm in diameter), and ozone (O3) precursors such as carbon monoxide (CO), volatile organic compounds (VOCs), and nitrogen oxides (NOx, which include NO2 and NO). There is also evidence of wildfire influence on enhanced O3 production. (8)
Exposure to pollutants contained in wildfire smoke has negative impacts on human health, with adverse respiratory, cardiovascular, and perinatal health outcomes that can lead to premature death. (9) In Canada, this can range from 54 to 240 deaths annually as a result of short-term exposure and 570 to 2500 annual premature mortalities from long-term exposure. (10) A recent toxicological study has suggested that PM2.5 from wildfires is more toxic per unit mass than PM2.5 from other sources. (11) It has become apparent that there are serious health risks from PM2.5 and O3 exposure below the regulatory standards, making the wildfire contributions to PM2.5 and O3 important to understand. (12)

Governmental agencies set air quality guidelines by recommending thresholds for selected air pollutants. In Canada, the PM2.5 threshold as implemented by the Canadian Ambient Air Quality Standard (CAAQS) is set at an annual mean of 8.8 μg/m3 and a 24 h mean of 27 μg/m3. (13) The U.S. equivalent, the National Ambient Air Quality Standard (NAAQS), is set at an annual mean of 12.0 μg/m3 and a 24 h average of 35 μg/m3. These standards reflect the recommendations of air quality standards published by the World Health Organization. (14) Extreme wildfire events are considered “exceptional events” in the NAAQS and the CAAQS since they do not reflect changes in anthropogenic emissions and are removed from the data when calculating the 24 h averages and the annual mean of PM2.5. (15) In the United States and Canada, there is no reporting standard about the impact of wildfires on air quality.
A major challenge to determining the impacts of wildfires on local air quality, and the focus of this paper, is determining when ambient air has been affected by wildfires. Overall, there is no widely accepted method to evaluate the influence of wildfires on local air quality, especially in populated regions. A combination of ground-based measurements, models, and satellite measurements has been used to make that determination, as summarized recently by Diao et al. (16) Understanding the contribution of wildfires to PM2.5 and other pollutants has become increasingly important with the increasing frequency and severity of wildfires as the climate warms...

Who cares? Chernobyl!

There were a lot of fires in British Columbia this summer, soon to fall down the memory hole along with the Deep Horizon Oil disaster, among other things. The British Columbia, Washington State, Oregon and California fires were caused by extreme heat, in many places heat so extreme, and so record breaking that people literally dropped dead from it.

However, according to the rhetoric I hear and the way I choose to interpret it, most people think that nuclear power is "too dangerous" implying that climate change is not "too dangerous."

We live in an age where insanity is celebrated and gleefully reported.

Nuclear power is "too dangerous" because...because...because...Chernobyl. Fukushima. ...and...of course...as a professor at Princeton University recently reminded me while talking about how solar energy is so great...Three Mile Island.

These three nuclear events outweigh everything...hundreds of millions of air pollution deaths at a continuing rate of around 18,000 deaths a day, the coasts of continents in flames, people dropping dead in the streets from heat...everything.

Why? Because Chernobyl is radioactive. This brings me to the first paper referenced in this post, the forest fires - probably induced by climate change, but who cares? - in the Chernobyl Exclusion Zone, where there are lots of living things that are not human beings.

So let's begin with the scary graphic introducing the paper on the Chernobyl Exclusion Zone forest fires:



Scary enough for you? Look at all those sinister looking radioactivity symbols flying up!

Now let's turn to the introduction to the text:

As a result of global fallout from atmospheric nuclear explosions and the Chernobyl nuclear accident, the Eurasian boreal forest represents one of the greatest stocks of long-lived anthropogenic radionuclides in the terrestrial environment, primarily 137Cs (T1/2 = 30.1 years). (1) Since the large wildfires in 1992, the fire hazard in the Chernobyl area has been viewed with serious concern. (2) These fire events are capable of emitting radionuclides (RN) into the atmosphere and can redistribute part of the already deposited RN. (3) These RN are found in topsoil layers, forest litter, and in the biomass. Emission of natural RN such as 210Po is also known to occur from wildfire events. (4,5) Wildfires in heavily contaminated areas generate radioactive smoke particles and thus an additional radiation exposure through inhalation or ingestion of contaminated foodstuff, following RN re-deposition. (6) The consequences of wildfires in the highly contaminated area around the CNPP (parts of northern Ukraine, southern Belarus and the western part of the Russian Federation) as well as emission factors or resuspension factors have already been investigated at a local level. (7−12) Evidence for long-range transport of RN from fires on an international scale is more recent. (1,13) Considerable efforts have been made by Ukraine, Belarus, and the Russian Federation to limit the consequences of fires in contaminated areas. (14,15) However, despite preventive measures (e.g., controlled fires, fire-breaks, access trails, limitation of fuel quantities in some areas, minimization of human presence) intended to limit both ignition and the spread of wildfires, they occur on a yearly basis in the Chernobyl area (16,17) and affect wildlife. (18) The Chernobyl ecosystem has regularly suffered from major wildfires notably in 1992, 1999, 2000, 2002–2004, 2006, 2010, 2015, 2016, and 2018 (15,19) with major impacts on the vegetation cover. (20) For a brief historic review of wildfires in contaminated areas, see the Supporting Information (SI).

Herein, we investigate the devastating April 2020 wildfires, which lasted for about 4 weeks in the Ukrainian part of the contaminated areas around the CNPP. The detailed geographic analysis and timeline is provided in the SI. The fire situation in the CEZ and bordering areas was characterized by a combination of numerous ignitions and subsequent spread of fires. Their magnitude varied according to different parameters: (1) biomass type, vegetation density, and location accessibility (forest, meadow, peatland, and marshland); (2) meteorological parameters (wind speed, wind direction, precipitation frequency, and amount). These multiple factors hindered firefighting, despite the mobilization of nearly 400 firefighters and 90 specialized aerial and terrestrial vehicles (two AN-32P airplanes, one Mi-8 water-bombing helicopter, heavy engineering equipment, and seven additional road construction machines of the Armed Forces of Ukraine). The first 3 weeks of April saw the development of particularly large and numerous fires. Two main fire areas were identified during this period: in the Polisske district and in the Kopachi-Chistogalovka-CNPP cooling pond (less than 12 km from CNPP). Daily information about burned areas including vegetation cover, contamination density, and radionuclide emissions were then published by the Ukrainian Hydrometeorological Institute (UHMI). (21) According to the UHMI, 870 km2 were burned in total, including 65 km2 in proximity to the CNPP and 20 km2 on the left bank of the Pripyat river...

Later on the authors turn to some background information, of which many people are aware because we talk far more about Chernobyl than we do about the more than 200,000,000 who died from air pollution since the reactor exploded:

Starting on April 26, 1986, and for a period of 10 days, the Chernobyl accident released harmful quantities of radionuclides of I, Cs, Te, Sr, Pu, and others (see Table S1, SI). Some regions of Belarus, Ukraine and the Russian Federation were seriously affected by the radioactive fallout from the CNPP accident. (29) About 6 million ha of forest including 2.5 million ha in Ukraine were heavily contaminated. In the most contaminated regions following the accident, the dominant forests were young or middle-aged pine and pine-hardwood stands, with a high fire risk. (8) The highest radionuclide deposition density occurred in the area surrounding the CNPP, in the so-called Chernobyl Exclusion Zone (CEZ) in Ukraine and in the Polesie State Radioecological Reserve (PER) in Belarus. The CEZ, initially about 30 km in radius around the CNPP was subsequently enlarged to an oblong area of 2600 km^2 with a 439 km circumference. It is located approximately 100 km north of Kiev (see Figure S1, SI). The CEZ is mostly covered by forest where radionuclides are distributed between soil, forest litter, and vegetation. Between 57 and 79% of the total 137Cs contamination is stored within the upper soil layer (0–2 cm). (30) Only a few percent of the 137Cs inventory is contained in the living biomass, where 137Cs behaves like potassium, its chemical analogue. During fire events in forested areas, the main source of radioactive aerosols is the burning forest litter. In comparison, the trees affected by the fire emit minor amounts of 137Cs and 90Sr and only trace amounts of Pu isotopes and 144Ce. (31,32) More information about radionuclide apportionment in the terrestrial ecosystem and fire impact is provided in the SI.

It is unlikely very much Ce-144 (cesium-144) remains after 35 years and I have no idea why the authors mention it other than to discuss historical fires, where some may have survived, for example the 1992 fire. It's half-life is 284.9 days. The date of the 1992 fires is not readily available, but if we choose July 15, 1992 arbitrarily assuming the fire was in the middle of summer, less than 0.4% of the original cerium present remained. As of today's date as of this writing, 10/30/2021, about two hundred billionths of it remain.

The half-life of cesium-137 in the paper is given both as a rounded number, 30.1 years, and the generally accepted number, 30.07 years one sees most often. A more recent and more precise figure, out of the ENDF file at the Brookhaven National Laboratory gives the half-life as 9.4925E+08 seconds, which works out to 30.08 years; whether the more precise figure is also accurate is not for me to say.

Using the ENDF value for the half-life it seems that as of this writing 44.1% of the original cesium-137 remains.

The text suggests that most of this remaining cesium-137 is sequestered in soils; the adsorption of cesium onto minerals is well known and this is unsurprising. Nevertheless, some radioactivity is taken up by the forest and ends up in the flammable litter, and the question is how much is volatilized in the fires, the question the paper with the scary graphic in the intro takes up.

Apparently these fires scare the shit out of people, particularly journalists. Here for instance is an article on this subject from the popular press, from the Atlantic, a publication I generally like even though, as we shall see below, the journalists there are incompetent to discuss most issues in science, as we shall see: FOREST FIRES ARE SETTING CHERNOBYL’S RADIATION FREE. At least, albeit surprising, the authors include a subheading that refers to a reason that the world's forests are burning up. Here's the subtitle:

Trees now cover most of the exclusion zone, and climate change is making them more likely to burn.

Let's return from my bad habit of bashing the woeful scientific ignorance of journalists and return to the scientific paper detailing how much radioactivity the fires released using the only units that matter, units of concentration.

The graphics give a feel for the concentrations in cubic meters - the volume of a breath is about 0.002-0.003 cubic meters for an average human adult. I will explain the "μBq" unit in the ordinate units below.

To wit:



The caption:

Figure 1. (Left) Airborne 238Pu and 239+240Pu vs 137Cs concentrations in the CEZ, Ukraine, April 2020. (Right) Airborne 238Pu concentration vs 239+240Pu concentration in aerosols sampled in the CEZ, April 2020.

A few years back, a correspondent on this website called up one of my old pro-nuclear posts to tell me all about a tunnel that collapsed at the Hanford Reservation, the site where historically plutonium for nuclear weapons was made. The point that was to be made, I guess, is that nuclear power is "too dangerous." To my mind, a correspondent using this particular example has his or head so far up his ass that, if he or she is wearing glasses, the screws in the frames might damage his or her duodenum.

Although I have had the distinct onus of attracting a broad array of anti-nukes, who want to raise specious points about nuclear energy, this on a planet where approximately 18,000 people die per day from air pollution because we don't use nuclear power, this particular correspondent sticks in my mind.

I've come rather to like the guy or gal in question, because he or she often whines that "I didn't say xxx or yyy or zzz" and - this apparently ranks in his or her mind as a crime against humanity worse than indifference over approximately 18,000 deaths per day - that I am guilty of producing a "strawman."

I have little tolerance for ignorance that kills people. To me, anti-nuke ignorance is precisely equivalent to anti-vax ignorance, worse actually because on the entire planet there have been few, if any, days where 18,000 people died from Covid in a single day.

Air pollution is a plague, even if we carry on day to day pretending that more important issues face us.

Nevertheless, again, I rather like the guy or gal, and take him or her off my ignore list from time to time to check in and hear him or her whine about "strawmen." One claimed "strawman" was when I offered the sarcastic remark that such as anti-nuke as this person is, might be more concerned about a single radioactive atom decaying in his or her tiny little brain than, say, climate change or air pollution deaths.

Neither of these disasters are, to my mind, necessary. The technology to eliminate them exists; it's not easy nor cheap to utilize this technology, and it will involve the minds of people with spectacular intellects, education and training, but it exists. It is more effective than tearing the shit out of virgin wilderness with diesel trucks and bulldozers to render that wilderness into industrial parks for wind turbines than will be landfill in 20 to 25 years or less. The use of this technology will require a race of human beings who once existed but have nearly vanished, a race of human beings who care more for the future than they do for the parochial concerns of the contents of their bourgeois pockets and pocketbooks.

So why do I like the guy or gal with the big concern about the collapsed tunnel at the nuclear weapons site? It has to do with measuring the depth of stupidity. One can actually learn a lot by measuring such a depth.

I had great fun, and learned an awful lot about the geochemistry of anthropogenic radionnuclides in writing this post, even though I would be the first to agree that no one should read it because it's desultory, boring, and extremely esoteric. (I write to learn.)

828 Underground Nuclear Tests, Plutonium Migration in Nevada, Dunning, Kruger, Strawmen, and Tunnels

In that piece I discussed the unit, the "μBq," in measuring the depth of stupidity associated with the "strawman" that this person, because it turns out that the unit very much involves a single atom. A "Becquerel" is the unit of radioactivity, named after the discoverer of nuclear decay, that corresponds to the decay of a single radioactive atom per second. One atom. To make sense of a "microbequerel" one must take its reciprocal, which will give the number of seconds that it will take to observe a single decay.

In the graphic immediately above, designed to show the ratio between plutonium and cesium, we see that most measurements of cesium-137 data points were below 10,000 μBq/m^3. This means that one must wait, on average, 100 seconds to observe a single decay of a single radioactive decay of a single atom of radiocesium in a cubic meter at 10,000, ten seconds at 100,000 μBq/m^3. . An adult human breath is about 0.002 to 0.003 cubic meters.

I'll post a relevant excerpt from my diatribe about the 828 nuclear tests:

The radioactivity described in the surface waters near Rocky Flats is not very impressive, although they surely would excite most anti-nukes into paroxysms of stupidity. 7.8 X10^-3 Bq means that one would need to wait more than two minutes (128 seconds) to observe a single nuclear decay of a single atom of plutonium in the water. One of the more abysmally stupid things that anti-nukes say is that "there is no safe level of radioactivity." This ignores the fact that potassium is an essential element, without which all life, including human life, would not exist on this planet, and that all of the potassium on earth - without extensive and hardly ever practiced laboratory processing - is radioactive, owing to the natural presence of potassium-40, (K-40) which has a half-life of 1.227 billion years. It is also worth noting therefore that when life evolved, potassium was more than twice as radioactive as it is now; life has always been bathed in radiation. A 70 kg human being contains about 140 grams of potassium (cf: Emsley, John, The Elements, 3rd ed., Clarendon Press, Oxford, 1998.) It is straight forward to calculate that the radioactivity associated with this potassium, given the isotopic fraction of K-40 in potassium, and its half-life. It works out to 4,250 Bq per body. Seawater, considering only it's potassium content and not the significant quantities of uranium and uranium decay daughters it contains, is more radioactive than Rocky Flats water, 1.29 X 10^(-2) Beq/liter.

K-40 has, by the way, a very energetic decay, well over a million electron volts per atom.

One often hears the statement, usually from poorly educated anti-nukes, that "there is no safe level of radioactivity." This is contradicted by the fact that every and any human being would die without being radioactive; a normal adult human being needs to have about 4000 nuclear decays in their flesh per second in order to live.

Facts matter.

The statement that "there is no safe level of radioactivity" is based on an oft applied assumption in radiobiology called the "Linear No Threshold" assumption, or "LNT." The "LNT" has never been definitively been proved, nor has it definitively been disproved. If it was true this will mean that some people - obviously not all people - are killed by an element of their bodies without which they could not live, so the construction of a control group will always be impossible, since the control group would be killed by eliminating potassium from their bodies.

The LNT model, which informs most safety information in connection with radiation to this day, is largely based on work conducted by a husband and wife research team working with mice, the Russells working at Oak Ridge National Laboratory, building on work . They had a co-worker, Richard Shelby, their Ph.D. student in fact, who on review of their data, discovered that they had underestimated the mutation rate in their control group, thus placing their data in serious question.

A Health Scientist at the University of Massachusetts, Edward Calabrese, has been on a quest - whether it is quixotic or not is not relevant - to have the LNT model discarded. He is not alone in this quest; others question it as well, but to me, it's angels dancing on the head of a pin. It may be true that some people occasionally have cancers induced by potassium-40 decay, but attempts at preventing this from ever happening would kill any experimental subjects involved in the matter.

Some of Calabrese's polemics make for interesting reading. Here are some examples:

The linear No-Threshold (LNT) dose response model: A comprehensive assessment of its historical and scientific foundations (Calabrese, Chemico-Biological Interactions 301 (2019) 6–25)

On the origins of the linear no-threshold (LNT) dogma by means of untruths, artful dodges and blind faith (Calabrese, Environmental Research 142 (2015) 432–442)

The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 1. The Russell-Muller debate (Calabrese, Environmental Research, 154 (2017) 435–451)

Support for rejecting the LNT comes from the known mechanisms for DNA repair; when these fail, cancer is often the result. If not addressed by innate immunological responses - most of us generate cancer cells fairly regularly but unless these cells possess immunological checkpoints, they are destroyed by an immune response - a cancerous disease state will result.

Calabrese is not alone in his considerations. The search terms LNT and validity in Google scholar will generate over 35,000 hits, over 3,000 in the last 5 years.

It is difficult however, in my view to argue that a single atom of cesium-137 decaying every hundred seconds, or even every ten seconds is going to result in mass fatalities.

The Chernobyl forest fire is hoopla if the concern is radiation. The more serious concern with that fire is the same as with every fire, including those in Canada, a fire clearly started by climate change which the half a century of wind and solar energy worship has failed miserably to addressed. That concern is air pollutants, the far more serious effect on "ELF" described above.

The Chernobyl fire paper does contain a few more graphics and comments. Here they are:



The caption:

Figure 2. April 2 to 24 137Cs average daily release rates reconstructed by Monte Carlo analysis using n = 15,000 samples (blue rectangles) and the associated standard deviations (orange bars). The green dashed line represents the number of observations used for each daily release assessed by inverse modeling.

The caption:

Figure 3. 137Cs airborne concentration maps (μBq·m–3) over the course of the April 2020 wildfire event in Ukraine. (A) Maximum observed concentrations; (B) maximum simulated concentrations; (C) maximum values based on hourly simulated concentrations (i.e. maximum time-resolved peak concentrations). The same color scale applies to all maps.

The caption:

Figure 4. Example of comparisons between simulated and observed airborne 137Cs concentrations at several European locations. The gray line shows the observed concentrations for each sampling period and the red line the simulated concentrations. The blue dashed line represents the simulated hourly concentrations.

The later sections near the end of the paper include this language:

The inhalation dose rate (0.013 μSv·h–1) would have also remained about 8-fold lower than the average ambient dose rate of 0.1 μSv·h–1 from the natural background. (6) When considering maximum airborne concentrations, the hourly dose rate estimation (1.7 μSv·h–1) by inhalation of artificial RN for firefighters is similar to the order of magnitude of the external exposure dose rate from the highly contaminated environment (1–10 μSv·h–1). It would have been 10 to 20 fold higher than the external ambient dose rate from the natural background radiation of 0.1 μSv·h–1 (range 0.07–0.23 μSv·h–1) and the internal dose of 0.18 μSv·h–1 (range 0.05–1.3 μSv·h–1), respectively. (6,63) Our estimates are consistent with those from previous studies, (6,62,63) which also indicate the predominant contribution of transuranic elements in the internal inhalation exposure. (6) These studies also point out that the dose received by firefighters because of smoke inhalation (internal dose) was only about 1% of the dose induced by ground shine, and the effective external dose would have exceeded the expected internal dose for firefighters even without protective equipment. (6) The dose of external radiation from the smoke (cloud shine) in case of fire was not taken into account as it is negligible (104–105 fold lower) as compared to the external dose (ground shine) from the contaminated environment. (32)

Chernobyl-labeled radionuclides aside, naturally occurring radionuclides with a high dose coefficient and that are prone to emission during a wildfire have to be considered. This is typically the case for, among others, 210Po (T1/2 = 138 days) as a progeny of the relatively long-lived 210Pb (T1/2 = 22 years), which accumulates in the biomass through foliar uptake. Polonium-210 has an effective dose coefficient of 3.3 10–6 Sv/Bq and 3.0 10–6 Sv/Bq for an adult of the public and for a worker, respectively, and given a type M solubility corresponding to chloride, hydroxide, volatilized Po, and all unspecified Po forms. Polonium is among the radioactive elements with a low fusion point (about 254 °C for elemental Po under 1 atm). The volatilization points of common polonium compounds are about 390 °C and thus much lower as compared to mean wildfire temperatures (>500 °C with maximum of 1000–1200 °C). (5) As a result, 210Po is easily emitted during a fire...

As the world burns, not just at Chernobyl, where people are prone to pay attention, but along the coasts and interiors of all the temperate and tropical continents, fires that fly down the memory hole, a little critical thinking would be in order.

Nuclear energy is not risk free, nor should it be required to be, unless some technology of lower risk exists, and I have convinced myself that no such technology exists. In times of climate change, much like potassium, its possible risks delineated with a dose of sarcasm, nuclear energy is essential to the survival not only to our way of life, but life itself.

Enjoy the rest of the weekend.

[hunter]

1. I find the NO2 discussion interesting as well.

How many people know their gas appliances are like mini-Chernobyls spewing out carcinogens? (Cars of course are worse, and it's not just the tailpipe emissions.)

California is officially discouraging gas appliances in new construction these days, mostly because of air pollution concerns, and the EPA is no longer awarding "Energy Star" ratings to gas water heaters for similar reasons.