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Discarded contaminated gas masks Within the 10km exclusion zone Chernobyl link

On the night of 26th of April 1986, plant operators at pripyat in the former Union of Soviet Socialist Republics undertook a stress test of the pressurized light water reactors that they where in charge of, unfortunately due to a combination of operator error, inherent design flaws and plain bad luck. The reactor reached super critical conditions, the water medium flashed off into super heated high pressure steam cracking the reactor vessel, subsequently reacting with the graphite medium this super heated steam broke down into its constituent Hydrogen and Oxygen. Until with a dull roar this explosive mixture detonated.

The explosion was so powerfull it teared the roof off the reactor vessel, and unseated the hundred ton steel container from its concrete casement, and sending a highly contaminated plume radioactive isotopes of debris ten thousand feat in the air, which subsequently spread across much of eastern Europe, this event came to be known as Chernobyl.

It is notable that before the Chernobyl disaster there was areas that had reached a similar or greater level of contamination such as Rocky Planes Flat, Mayak, or Los Alomos, but all these areas where associated with the manufacture or storage of components for fission or fusion devices and as such operated under a blanket of secrecy and denial.

Chernobyl with its very visible debris plume, close to unfriendly nations and the large numbers of people that had to be evacuated meant that the contamination was impossible to hide, this was exacerbated by the initial unwillingness of the soviet government to fully disclose the scale or scope of the disaster. This helped exaggerate the crisis in the eyes of the west and has arguably, except for the dropping of fat man and little boy been the single most important moment of fixing a negative impression of nuclear technology in the eyes of the general public.

Operating in a vacuum of true information as the Soviet union still had a few more years left to play out, Chernobyl in popular imagination was considered a dead and sterile place, to a much milder extent this overreaction view was shared by the scientific community. At this point it was very well understood that the damage ionizing radiation could do, particular in the form of processed mineral salts or a soluble solution or radioactive elements.

However when western researchers finally gained adequate access to Chernobyl, to allow for long term studies to take place, what they found surprised them to say the least, rather than being a ecologically dead or damaged place , life was thriving in the 30km exclusion zone, with a wolf population and deer population several times that of surrounding uncontaminated land. Clearly life was more resistant than previously expected to nuclear material contamination, in particular the larger animal populations such as European bison (Bison bonasus) did not display the amount of birth defects that was initially expected. One hypothesis is that the wildlife is proving so resistant due to induced radio resistance , this is the phenomenon where after being exposed to ionizing radiation, and given a rest period a organism will the be better to resist further doses as a result. Due to the contamination in Chernobyl being, primarily made up of several hot spots and larger areas of less pollution it is possible that as long as the animals did not linger for too long in a hot spot they are giving themselves time to recover. Although this phenomenon has been intensively documented in laboratory conditions, Chernobyl is one of the few places that it has and indeed could be studied in the wild.

This is a graph showing the effect of fractionation on the ability of gamma rays to cause cell death. The blue line is for cells which were not given a chance to recover while the red line is for cells which were allowed to stand for a time and recover.

Figure 1:Effects of a pre dosing of  gamma radiation on the subsequent ability of cells to resist radiation damage.

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Although a slightly more grim alternative hypothesis is that life in the shadow of a melted PV LWR1 8 series soviet reactor, is less detrimental to  large mammal populations, than is co existing next to normal human habitation, and what we consider healthy populations is actually hopelessly skewed, due to this.

chernobyl wildlife

White tailed eagle  Haliaeetus albicilla scavenging European wolf Canis lupus lupus Chernobyl. 

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The Chernobyl experience has been credited with opening researchers eyes in regard to radio resistant extremophiles, although previously well aware of some forms of bacterium and simple creatures such as Tardigrades, that could tolerat  the Chernobyl experience, it has since been discovered that larger plants, trees and even large mammals have surprising ability to withstand radiation, these normally occur in areas of high natural radiation, such as where there is high levels of natural uranium in the soil, or alternatively areas that end to pool areas of Radon gas.

This renaissance in radio resistant has turned up a number of interesting oddity s such as Hermococcus gammatolerans a hot vent dwelling poly-extremophile Archean, that has been measured to be able to resist a extraordinary 30,000 grays of ionizing radiation, to put that in perspective after a standard x ray you will absorb  in the region of 0.3 Gy, while above 5 Gy would put an average human at the risk of death.

Extremly radioresitant organisms such as gammatolerans have been postulated as a possible method for combatting cancer, viruses, and some genetic conditions due to their very robust DNA repair mechanisms.

Thermococcus gammatolerans.jpg

To conclude from the previous examples it is fair to say that some fears about nuclear contamination are overblown, and the current political climate does not accurately reflect the risks of nuclear contamination, particular when compared to the unheralded risks of conventional fossil fuel energy production, which not only adds to the greenhouse effect through C02 emissions but also causes a surprising amount of direct harm due to particulate inhalation.

Indeed risk analysis determined that once the original plume of radioactive isotopes had decayed. Health out come where better for residents who had stayed in the 30km of exclusion zone then those who had moved to large nearby cites such as Minisk or Kiev, however one small benefit of this overstatement of the risks is the creation of ersatz wildlife sanctuaries. As such these create not inconsiderable wild life hot spots, that are host to many species that are on the decline elsewhere, interestingly these sites seem to be safer in the long term than purpose made and designated sanctuaries,  as they are less vulnerable to development such is the fear of radiation.

 

 

 

 

 

 

 

Hermococcus gammatolerans

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