Finland, Sweden, and Norway have seen unusual low levels of human-caused radioactivity in recent days, a rise that is harmless to humans, who according to a Dutch institute has found its source in western Russia, while a French NGO has ruled out a lead to Latvia.
The Comprehensive Nuclear-Test-Ban Treaty Organization, whose stations also measure increases in civilian radioactivity, posted a map on Twitter showing the source’s likely area of origin, according to its measurements.
The area covers roughly the southern third of Sweden, the southern half of Finland, Estonia, Latvia, as well as a large area surrounding Russia’s northwestern border, including St. Petersburg.
These isotopes (cesium 137, cesium 134, and ruthenium 103, among others) are most likely of civil origin. We are able to indicate the likely region of the source, but it is not part of the mandate of the CTBTO to determine its exact origin,” Lassina Zerbo, secretary-general of the Vienna-based international organization, commented on Twitter.
Russian nuclear power producer Rosenergoatom has denied any incidents at the two power plants it operates in the sector.
“No anomalies were recorded at the Leningradskaya and Kolskaya nuclear power plants,” a spokesman told Russian news agencies. Emissions “did not exceed control values for the specified period” and “there were no incidents related to radionuclide release beyond established levels,” he continued.
According to calculations by the Dutch Institute for Public Health and the Environment (RIVM), “radionuclides come from the leadership of Western Russia” although the measurements do not identify a more precise location.
The nuclides found are very artificial and therefore of human origin. And their composition “may indicate damage to a combustible element in a nuclear power plant,” the Dutch authority said in a statement.
In addition to Russia, Finland and Sweden operate nuclear reactors in the area, but no incidents have been reported. The Baltic countries do not have an active reactor, as Lithuania has closed its only nuclear power plant of Soviet origin as part of its entry into the European Union.
On the other hand, radioactivity problems have been reported in recent years in conventional power plants in Latvia. They used wood from parts of Belarus, including the Gomel and Moguilev areas in the east of the country, which had been particularly contaminated by the fallout from the Chernobyl nuclear disaster.
The operator of the heating and electricity network in the Latvian capital Riga apologised in 2018 for using wood containing radioactive elements. And the company, Rigas Siltums, announced in a statement on 17 June that it had launched a research project “on the control of the radioactivity of wood and ash” of its power plants.
But according to Criirad, an anti-nuclear NGO specializing in radioactivity control, some of the isotopes detected can rule out this trail.
“The detection in Helsinki of short-term radioactive elements, cesium 134 (two-year period) and especially ruthenium 103 (39-day period), excludes that it is solely the burning of biomass contaminated by the fallout from Chernobyl in 1986,” Bruno Chareyron, a nuclear physics engineer and director of the Criira laboratory in Valencia, told AFP.