Russians release details on radiation

MOSCOW — Russia’s state weather and environment monitoring agency on Monday released new details about a brief spike in radioactivity after a mysterious explosion at the navy’s testing range.

The Aug. 8 incident at the range in Nyonoksa on the White Sea killed two servicemen and five nuclear engineers and injured six others.

The incident has been surrounded by secrecy and fueled fears of increased radiation levels. Authorities reported a rise in radiation levels in nearby Severodvinsk but insisted the increase didn’t pose any danger.

Russia’s state weather and environmental monitoring agency Rosgidromet said Monday that the brief rise in radiation levels was caused by a cloud of radioactive gases containing isotopes of barium, strontium and lanthanum that drifted across the area. The agency said its monitoring has found no trace of radiation in air or ground samples since Aug. 8.

It has previously said that the peak radiation reading in Severodvinsk on Aug. 8 briefly reached 1.78 microsieverts per hour in just one neighborhood — about 16 times the average. Readings in other parts of Severodvinsk varied between 0.45 and 1.33 microsieverts for a couple of hours before returning to normal.

The authorities said those readings didn’t pose any danger, and that the recorded levels were several times less than what an airline passenger is exposed to on a longhaul flight.

Alexei Karpov, Russia’s envoy to international organizations in Vienna, told the Comprehensive Nuclear Test-Ban Treaty Organization on Monday that “the tragic accident that occurred has nothing to do with nuclear tests.”

But, he said, the tests at the range “were related to the development of weapons, which we had to start creating as one of the retaliatory measures in connection with the U.S. unilateral withdrawal from the Anti-Ballistic Missile Treaty in 2002,” according to a Russian Foreign Ministry transcript.

Contradictory statements from the authorities and their reluctance to reveal details of the explosion have drawn comparisons to the Soviet cover-up of the 1986 explosion and fire at the Chernobyl nuclear power plant, the world’s worst nuclear disaster.