Jennifer Lake's Blog

December 4, 2017

Petkau Effect: devastating low dose radiation

In 1972, more than 46 years ago, the nuclear science world got its first definitive proof of the devastating effects of low-level radiation on humans and the environment. The messenger of that news was Dr. Abram Petkau who worked for the Canadian nuclear establishment. His work lives on as the Petkau Effect.

Dr. Abram Petkau*

I recently obtained a book The Petkau Effect; Nuclear Radiation, People and Trees by Ralph Graeub, updated fourth edition 1992. Dr. Ernest Sternglass provided a lengthy introduction including a description of damage to biological cells:

“…Petkau and his co-workers showed that the cell membrane damage was due to a completely different biological mechanism than the direct hit on the DNA molecules in the nucleus of cells that had been observed at the high doses and dose-rates of atomic bomb detonation or medical exposures. It turned out that the cell membranes were destroyed as the result of the action of a negatively charged, short-lived form of ordinary oxygen, the so-called O2-negative free radical, produced by the absorbed radiation from the life-giving oxygen dissolved in the surrounding fluid. This highly toxic form of oxygen diffused to the outside of the membranes, where it initiated a chain reaction that dissolved the membrane in a matter of minutes to hours, causing the cell to leak and die.
“It became clear that a single O2negative molecule was sufficient to destroy an entire cell, so that only a handful needed to be produced per cell-volume at very low dose rates. But at high dose rates, many millions would be formed in the same volume in the lifetime of the molecule. This was a form of overkill, much like the case of a balloon where a single dart is enough to destroy it, and throwing millions of darts at it only represents a waste of energy. In fact, the more free radicals are created in a given volume, the more they tend to run into each other causing them to become deactivated to harmless ordinary oxygen. Thus, per unit of energy deposited in living tissue consisting of cells, high doses given at the rate of 10,000 rads per minute were found to be 100 billion times less efficient in destroying a cell than at one ten-millionths of a rad per minute, the rate at which we experience background radiation.
“As described in The Petkau Effect, the consequence of the enormously greater efficiency of radiation at low, as compared to high, dose rates is that the dose-response curve rises very rapidly at small doses…
“…As discussed by Graeub, the indirect free radical type of damage that dominates at low dose-rates is particularly serious for the cells of the immune system, which must be constantly renewed from their progenitors in the bone marrow. This is especially true for strontium-90 and other bone-seeking isotopes chemically similar to calcium that concentrate in bone and emit relatively long-range beta particles or electrons…”


*Dr. Ernest Sternglass:

*** “Graeub presents enormously important but little-known evidence that nuclear plant releases are also contributing to the production of acid rain, ground-level ozone and the death of forests… the death of trees has reached epidemic proportions…   Again, the indirect effects of radiation through the production of free radicals on ordinary air pollutants and the cell membranes of plants seem to be the reason…” [into p.25, The Petkau Effect]

*The Petkau Effect:*

“In 1972 the scientist Abram Petkau at the Canadian Atomic Energy Commission’s Whiteshell Nuclear Research establishment in Manitoba, made an accidental discovery deserving of the Nobel Prize. Petkau irradiated artificial cell membranes under water, using phospholipid membranes which are similar to the cell membranes in living cells. He discovered that if the irradiation continued over an extended period, the membranes would tear after a much lower total absorption of radiation dose than if this total dose were emitted in the form of a short burst, as used for x-ray film. A living cell consists of a cell membrane and a cell nucleus. But the cell membrane is not only there to hold the watery cell plasma together; it has many important functions in biological processes. These tasks have been compared with those of an entire industrial corporation. Thus, intact cell membranes are essential for a healthy life. What Petkau discovered was the following: A short term irradiation of 26 rads per minute (i.e., a high dose rate) from a large x-ray machine required the high total dose of 3,500 rads in order to destroy the cell membrane. However, with protracted radiation of only 0.001 rads per minute (i.e., a low dose rate) from radioactive table salt (Na22Cl) dissolved in water, a total dose of only 0.7 rads was required to break it. Thus, in the case of low-level, protracted irradiation, a 5,000-times smaller total dose was necessary. This was truly an incredible discovery.” [p86]


“Ionizing radiation affects the structure and chemistry of the cells. Ions [or electrically charged molecules] are formed, and..may be split apart, forming radicals. Radicals are pieces of molecules that are chemically very aggressive and can form new compounds which are foreign and in some cases toxic.” [p26]
“In the cell fluid, which contains dissolved oxygen, the radiation can cause the formation of a highly toxic, unstable form of oxygen. These so-called ‘free radicals of O2- [or superoxide anions] are attracted by the cell membrane, where they set off a chain reaction that successively oxidizes the molecules of the cell membrane; this weakens or even destroys the membrane. Thus, unlike the case of the cell nucleus [containing DNA], the damage is not the direct result of radiation; rather it occurs indirectly, as the result of the ‘free radicals’ created by the radiation.
…The fewer free radicals present in the cell plasma, the greater their efficiency in producing damage. This is because the free radicals can deactivate each other to form ordinary oxygen molecules. Thus, the fewer free radicals created by radiation in a given volume –and smaller doses create fewer of them– the greater their chances of reaching..the cell wall without first being subjected to a recombination.
Conversely, the more free radicals created..the faster they recombine and become ineffective before they can reach and damage the membrane. In addition, there is a further effect. Cell membranes generate an electrical field in the cell plasma which attracts negatively-charged molecules such as the highly toxic free radical. Computer calculations have shown that the greater the concentration of free radicals, the weaker the attraction by the electric field. Thus, if the concentration of radicals is high, [they] are even less capable of reaching the cell wall than if the immediate concentration of radicals is very low.” [p88]
“Numerous scientific studies of the past..have shown that indirect cell membrane damage must also be effective in biological systems, even at the most minimal doses of 10-100 mrads [millirads] (0.1–1mGray), i.e. in the range of natural radiation, fallout and emissions from a nuclear power plant.” [p90]


* Low-dose radiation effects on insects living near nuclear power plants are under close observation by scientific illustrator Cornelia Hesse-Honegger, who says in her own words: “When Chernobyl happened, I knew it was time for me to act… I traveled to Sweden, which was also affected by the radioactive plume, to look for mutated bugs… They stay near the same piece of ground for generations, making them excellent subjects for the study of..prolonged radiation… I found terribly deformed insects, even though the levels of radiation there were relatively low… In the southern part of Switzerland, which was highly irradiated by Chernobyl, I collected three pairs of [fruit] flies and bred them in my kitchen… From the first generation on, the flies were deformed. In 1988, I published this and similar data…  In 1992, I decided to start a systematic study of the effects of nuclear power, traveling to nuclear plants around the world and gathering..bugs living around them… What I found was..a consistently higher rate of deformations.”


“The first signs of forest death coincide with the first appearance of artificial radioactivity in our environment. [p162, The Petkau Effect] …Of all civilization-induced pollutants, radionuclides have had the highest rate of increase relative to their natural rate of production. The military and civilian use of nuclear energy is responsible for the massive increase in the level of radioactive pollutants… For instance, the atmospheric concentration of krypton85 has increased by millions…  [L]arge accumulations of radionuclides and their daughter products in leaves, needles and the soil due to the bomb fallout of the ’50s and ’60s have been proven with certainty. This is also true for plutonium, americium, tritium and carbon14… [It’s] now determined that forest death has been strongly increasing throughout the Northern Hemisphere since the time that the long-lived radionuclides from the A-bomb tests started spreading to the root areas of trees… Thus, the observed delay of the damage… [pp155-157] “Reduction of its concentration in the air by dry sedimentation or wet precipitation is only minimally successful. This is a very serious factor, for 97% of the krypton remains in the atmosphere and is eliminated only by..radioactive decomposition which may take decades… The long half-life of krypton means irresistable build-up in the environment… If the krypton reaches even one percent of the maximum permissible concentration in the air (300 nCi/m3), measurable global changes in the electric conditions of the atmosphere will begin to occur… It might be possible for lightning bolts in widely separated regions to be connected by electrical feedback. This may cause unexpected changes in the weather.” [p140-141]




“During the 1950s and 1960s, there must have been a global wave of air pollution which caused the initial damage. It was certainly not our cars with NOx emissions and photosmog that were to blame, nor is it likely that SO2 was solely responsible…[p123]
“The acid rain hypothesis [in forest death] is based on the assumption that sulphuric, nitric, hydrochloric and carbonic acids lead to chemical reactions in the soil. This liberates plant-toxic aluminum and manganese ions, damaging to root hairs…. However, if SO2 (sulphur dioxide) is dissolved in water in the lab, nearly the only thing that is produced is sulphurous acid (H2SO3) which is much weaker than sulphuric acid (H2SO4). In order to produce the very acidic sulphuric acid, it is first necessary to oxidize the sulphur dioxide (SO2) to sulpher trioxide (SO3)… It is thought that photo-oxidants such as ozone and hydrogen peroxide (generated by the effect of sunlight on NOx’s and hydrocarbons) act as catalysts or promoters of the reaction. However, artificial radioactive substances may have the same effect. Artificial radiation produces radiant energy and can directly oxidize SO2 to SO3, or form ozone from atmospheric oxygen. Radiolysis in water can form hydrogen peroxide directly, and may even produce NOx from atmospheric nitrogen. [p124]
“At a 1975 meeting of the International Atomic Energy [Agency], a number of very interesting correlations involving radioactivity were presented by the scientist K.C. Vohra of the Bhabba Atomic Research Center at Trombay, India… Vohra began with the assumption that so-called condensation nuclei are constantly forming in our atmosphere by means of chemical reactions of various substances. He was able to determine by experiment that this condensation-nucleus formation increased somewhat in the [sulphur dioxide]-rich exhaust gases under the effect of sunlight or cosmic radiation. However, when radioactive gases were released from the nuclear power plant, condensation-nucleus formation increased rapidly. The SO2 was quickly oxidized to SO3, which in turn leads to sulphuric acid, which also forms condensation nuclei much more readily.” [p125]
“Moreover, ozone can be produced in the lower atmosphere by radioactivity, utterly independent of sunlight. Thus, such radioactive inert gases as krypton85 and xenon133, which are released unchecked in all atomic fission processes, are known as effective ozone-generators.” [p132]

……….more to come: quotes from The Petkau Effect and info on oxygen free radicals…………..


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