Mystery cloud over Estonia in June

Andres Einmann
The Sosnovy Bor NPP lies just 70 kilometers from the Estonian border. Officials say there have been no problems at the plant.
The Sosnovy Bor NPP lies just 70 kilometers from the Estonian border. Officials say there have been no problems at the plant. Photo: Peter Kovalev/TASS/Scanpix

The Environmental Board’s Harku radiation monitoring station picked up a cloud of radioactive particles of unknown origin that passed over Estonian in mid-June. Stations in Finland and Sweden have also registered radioactive particles. While Dutch officials believe the radioactive particles are from western Russia, the latter denies it.

The board’s Harku monitoring station detected very small quantities of cesium, cobalt and ruthenium isotopes in the air. Teet Koitjärv from the board’s radiation department said that the quantities of isotopes were negligible and only detectable under laboratory conditions.

The particles were discovered when the filters of the Harku station were analyzed on June 14-21.

“Such quantities pose no health risks,” Koitjärv said, adding that radiation monitoring is active 24/7 in Estonia.

The Environmental Board has no information to suggests where the radioactive isotopes came from. The Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO) Preparatory Committee has published a preliminary map of the potential spread of the isotopes. The map shows that the particles were detected over much of northeastern Russia, Estonia and Latvia, as well as parts of Lithuania, also Finland and Sweden. The westward fringe of the cloud of particles covered parts of Denmark and southern Norway, stretching over the North Sea.

Nordics pick up on radiation

Minister of Foreign Affairs Urmas Reinsalu contacted his Finnish, Latvian and Lithuanian colleagues to exchange information on the particles on Sunday.

“Several counties have reported a slight rise in radioactive isotope concentrations in northeastern Europe. Even though these levels are in no way harmful to humans, it is in our interests and those of international security to detect the origin of this hike as it is surely manmade,” Reinsalu said on social media.

He added that Estonia is in touch with the International Atomic Energy Agency (IAEA) and other countries.

The radiation and nuclear safety watchdogs of Finland, Norway and Sweden said last week they had discovered harmless concentrations of radioactive isotopes in Finland, southern Scandinavia and the Arctic.

In early June, iodine-131 isotopes were found in Norway, with cesium-134, cesium-137, cobalt-60 and ruthenium-203 isotopes detected in Sweden and Finland.

The Swedish Radiation Safety Authority said on Tuesday that it is impossible to say what could have caused the spike in radiation. Finnish and Norwegian authorities have also discussed a potential source.

The Dutch public health and safety authority said on Friday that it has analyzed data from the Nordics, with calculations suggesting the isotopes came from the direction of western Russia.

“The radionuclides are artificial, meaning they are manmade. The makeup of the nuclides could indicate a damaged fuel element in a nuclear power plant,” the Dutch agency said, adding that a more specific source cannot be identified because of limited data.

No problems

Russian news agency TASS wrote that according to information from national nuclear power operator Rosenergoatom, the two nuclear power plants in northeastern Russia have not reported any problems.

The Leningrad nuclear power plant near St. Petersburg and the Kola NPP near Murmansk are working normally and radiation levels are within permitted levels, TASS reported.

A spokesperson for Rosenergoatom told TASS on Saturday that radiation is unchanged in and around the Leningrad and Kola plants.

“Both plants are operating normally. We have heard no complaints in terms of functionality,” TASS quoted the spokesperson as having said. No incidents of radionuclides released into the air have been reported.