Strong radioactive release finally recognized in Russia: analysis of the french association for control of radioactivity in the West (ACRO)

Updates at the end of the document:

  • Russia recognizes ruthenium contamination, but denies leak, Nov. 20 2017
  • Russia tries to be reassuring, November 24
  • IAEA data leaked, November 27
  • Result of the “independent” survey led by Rosatom, December 8
  • Rosatom recognized ruthenium-106 released into the environment, December 14
  • Ruthenium 103 was also present in the rejection, February 5 2018

The Institute for Radiation Protection and Nuclear Safety (IRSN) has just announced (in French and English) that traces of ruthenium-106, a radioactive element, detected in Western Europe last September, were probably due to a massive release, on the order of 100 and 300 terabecquerels, “somewhere between the Volga and the Urals without it being possible to specify the exact location of the point of discharge with the available data.

The Institute adds that “the consequences of an accident of this magnitude in France would have required locally to implement measures to protect populations on a radius of a few kilometers around the place of rejection.

Still according to the IRSN, the release would have taken place during the last week of September 2017 and would be finished.


Ruthenium 106 is a radioactive fission product from the nuclear industry that does not exist in its natural state. Its half-life is a little over a year (373 days), which means that the present amount is halved each year. By disintegrating, ruthenium-106 is transformed into rhodium-106, which is also radioactive with a half-life of 30 seconds. Each decay of ruthenium-106 goes with the disintegration of rhodium-106, shortly after. Thus, the ruthenium-rhodium pair should be considered which doubles the quantity released of 100 and 300 terabecquerels announced by the IRSN.

Rhodium-106 will be responsible for most of the dose caused by the incorporation of inseparable pairs of radioactive isotopes.

Origin of the release

In case of release from a nuclear reactor, various radioelements are detected. Here, since ruthenium-106 and rhodium-106 are the only radioelements to have been identified, the origin can not be a nuclear reactor. On the other hand, it may be the accidental release of a spent fuel treatment facility or the manufacture of radioactive sources.

ACRO sometimes detects the ruthenium-rhodium pair around the Areva factories in La Hague. In 2001, two incidents in these factories led the association to demonstrate that the operator, still known as Cogéma, underestimated its ruthenium-rhodium releases into the atmosphere. In May and again in October 2001, the quantities actually released were about 1,000 times higher than what had been announced (see technical note in french). Studies following this ACRO alert showed that atmospheric ruthenium-rhodium releases have been systematically underestimated.

In February 2016, ACRO had again detected this pair of radioelements around the La Hague plants, which was indicative of greater atmospheric release than usual, possibly indicative of undeclared dysfunction.

Quantity released

IRSN announces a source term in Russia of 100 and 300 terabecquerels for the only ruthenium-106, and therefore the double also taking into account rhodium-106. A terabecquerel is 1,000 billion becquerels.

As a comparison, the authorization of atmospheric discharges from the Areva factories in La Hague is 0.001 terabecquerel (1 GBq) per year for beta-gamma emitters (including ruthenium-rhodium) other than tritium, rare gases and iodines. For liquid discharges, for the only ruthenium-106 released at sea, the limit is 15 terabecquerels per year.

The quantity released during the incident reported by the IRSN is therefore considerable and this event should be classified at Level 5 of the INES international scale. Chernobyl and Fukushima were at 7, which is the maximum level. However, no information is available on the IAEA website.

Provisional conclusion

60 years after the Kychtym disaster in the Urals and more than 30 years after the Chernobyl disaster, the fact that an event of this magnitude can remain secret for more than a month is incredible. This is particularly serious for local populations who have been exposed without any protection, as in 1957 and 1986.

It should be noted that as early as October 11, the Bundesamt für Strahlenschutz in Germany pointed to the South of the Urals (communicated in German and English), stating that IRSN shared this point of view. There was therefore no progress in a month in identifying the origin of this rejection.

Is such secrecy explained by the fact that a military installation is involved? Russia has denied being behind this rejection. It should publish all its measurement data in the environment.


Several websites are targeting the Mayak nuclear complex in Chelyabinsk Oblast as the source of this contamination, without our being able to validate these claims. Originally, this secret military-industrial complex is designed to manufacture and refine plutonium for nuclear warheads and has become infamous for its serious nuclear accidents, including that of Kychtym. The site is still active and serves as a spent fuel treatment center (operator’s website).

Russia recognizes ruthenium contamination, but denies leak , Update on November 20

At the request of Greenpeace Russia, it was the Russian meteorological agency that finally admitted that the origin of the leak is in Russia (release in Russian). The press releases is entitled: “extremely high and high pollution”. Meanwhile, the state-owned company Rosatom still denies being at the origin of this pollution. (release in English). In its press release, the weather agency does not give the ruthenium-106 or rhodium-106 contamination, but rather the total beta contamination of aerosols. But we can suppose that the excess is essentially due to this couple of radio-elements.

The highest concentration was found in Argayash, in Chelyabinsk Oblast, which includes Mayak and Kychtym between September 26 and October 1: 7,610 × 10-5 Bq / m3, or 986 times more than is usually measured in this station. In Novogorny, still in the Chelyabinsk Oblast, it was 5,230 × 10-5 Bq / m3 these days, 440 times more than the usual values. Excessive radioactive aerosol values ​​were also detected in the North Caucasus, up to 2,147 × 10-5 Bq / m3, or 230 times background noise, and in Tatarstan. Other data is available in this document in Russian.

It is now confirmed that a serious rejection has taken place on a Russian nuclear installation which is still secret. But the meteorological agency has apparently not launched a warning and it is the local populations, who live in an already highly polluted environment, who have been exposed. What are its tags for? The meteorological agency explains that the levels recorded are well below the local limits set at 4.4 Bq / m3. A non-event in Russia.  These concentrations are very high compared to what is usually measured and is the unambiguous signature of an abnormal rejection. On the other hand, the atmospheric concentrations announced do not require sheltering or evacuation, even under French standards.

The measurement station at Argayash (Aragasy), where the highest concentration has been measured, is about thirty kilometers from the Mayak nuclear complex. Near the point of discharge, pollution may be higher. Independent environmental measures are essential. The Russian meteorological agency also mentions fallout from 10 to 50 Bq / m2 and per day, in places. the IAEA website still does not indicate anything.  It should be noted that the weather agency also mentions radioactive iodine pollution in the Obnisk region (Обнинск), located about 100 km southeast of Moscow. Concentrations reached 1.85 × 10-3 Bq / m3 on 18 and 19 September and would be due to a local research center.

On November 21st, IRSN stated in French media that the results of its modeling gave much higher values ​​in the immediate vicinity of the discharge point. But, if the tags whose results have been published are not under the winds at the time of rejection, it remains compatible. And the Institute adds: “We can therefore ask ourselves the question of the role of the IAEA. It is not normal to arrive at this situation. It is not normal to observe ruthenium in the air of all Europe, without ever knowing the source.

Russia tries to be reassuring, Update on November 24

The regulator of agricultural products Rosselkhoznadzor issued a statement (in Russian only) denying the contamination of Russian agricultural products. It  talks about panic in the grain market that would be due only to rumors and media speculation, but gives no measurement results.
Meanwhile, the Institute of Nuclear Security of the Russian Academy of Sciences (IBRAE RAS) announced the creation of a commission of inquiry in a statement (in Russian only) whose purpose is to determine the origin ruthenium and rhodium pollution. It is also reassuring by saying that the levels found in Russia are largely in the norms and has already concluded that Rosatom, the Russian national company, is not involved. And Rosatom will inform the public of the results of the investigation.
In the absence of an independent laboratory on site, there is still room for improvement in terms of public transparency and radiation protection in Russia.

IAEA data leaked, Update on November 27 

ACRO uploads data collected by the IAEA on ruthenium pollution detected in Europe that the UN agency refuses to make public. This table, dated October 13, 2017, does not contain any Russian data.  As for Rosatom, the Russian state-owned company,  it invites journalists and bloggerson its Facebook page  to visit Mayak, which, according to Western journalists, has become the cradle of ruthenium. On the agenda, “literacy” on ruthenium.

Result of the “independent” survey led by Rosatom, Update on December 8 2017

The state-owned nuclear company Rosatom held a press conference to communicate the findings of the “independent” ruthenium-rhodium contamination survey carried out in late September throughout Europe: it is not responsible for this pollution. Nothing on his website for the moment … To be continued!

Only an independent international inquiry will shed light on this rejection. Russia could start by publishing all its environmental data in the suspected area.

Rosatom acknowledges releasing ruthenium-106 in the environment, routinely, Update on December 14, 2017

According to News Agency AP, Yuri Mokrov, an adviser to the Mayak Nuclear Center’s managing director, acknowledged that processing spent fuel leads to releases of ruthenium-106 into the environment. He then added that Mayak plant is not the cause of the abnormally high rejection that was detected throughout Europe last September. According to him, discharges would be minimal and hundreds of times below allowable limits. Authorized levels are not given in the article.

Our summary:
Russia first didn’t detect radioactive ruthenium detected throughout Europe;
Then, following the calculations made in Germany and France that pointed to the Urals, the country ended up admitting to having detected it at extremely high levels, but without danger. In fact, the advertised levels are much higher than what is measured routinely, but do not require any particular protection measure. The measurement of an air pollution is done by filtering the air for several days. This may be a long-term average that mitigates the peak pollution. The measurement period is not given.
Rosatom, the state nuclear industry in Russia denies any involvement in the rejection. It sets up an “independent” commission which concludes in the same direction and which brings out the thesis of the fall of a satellite. And there, all of a sudden, Rosatom recognizes regular rejections of ruthenium-106 in the environment and declares these rejections are within the admissible limits. And there wasn’t any particular incident to report. This means the limit must be very high.

The conclusion is that Russia has not changed much since Chernobyl. Without an independent laboratory on site, glasnost did not affect the nuclear sector.

Ruthenium-103 was also present in the rejection , February 5 2018

A meeting with international experts took place in Russia at the end of January 2018 about this ruthenium case, including IRSN. It appears that in some countries ruthenium-103 was also present in the radioactive cloud. Surprisingly, there has been no official communication so far, which gives some indication of the potential source of this contamination. On January 22nd, the Bundesamt für Strahlenschutz in Germany was still saying that there was only ruthenium-106.

 The half-life of ruthenium-103 is 39.26 days, which means that it disappears much faster than ruthenium-106, which has a half-life of 373.6 days. And so the nuclear fuel at the origin of the rejection must not be out of the reactor for a long time: 3 to 4 years maximum. However, in general, the treatment of spent fuels is done on older fuels.

 The Russian press deduces that this exonerates the Mayak site. It does makes it possible to exclude a priori vitrification which was strongly suspected until now, unless, for some obscure reason, young fuel could be treated and the residues vitrified. On the other hand, the manufacture of radioactive sources is generally done on “young” spent fuel. And Mayak makes sources …

French press mentions the commission by CEA and INFN in Italy to the Mayak nuclear complex of a source of cerium-144 for a physics experiment. However, the production of this source requires the treatment of “young” fuels, less than 5 years old. The article speaks of troubling coincidence.

This rejection is mysterious enough to put everything on the table and we hope for an official communication from the international experts present in Russia.

On February 6, IRSN posted a briefing note in French and English and a report in English only summarizing its investigations confirming the detection of ruthenium-103 and studying the hypothesis of the manufacture of a source of cerium-144. The report is rich in information.

Article initially published on November 11, 2017 on the ACRO website.

ACRO is a French non governmental organisation that operates a laboratory for radioactivity analysis. It was created in 1986 as a response to people’s demands for information and reliable independent testing. It is a member of NTW since 2013.