Tiny sample of xenon confirms nuclear test

A miniscule amount of radioactive material produced from the North’s nuclear test earlier this month has been detected in South Korea, the Ministry of Science and Technology said yesterday.
“This is an official confirmation that North Korea conducted an underground nuclear test on Oct. 9,” the ministry said.
The amount detected in the South Korean atmosphere was extremely miniscule, and not harmful to human health, the ministry said.
“The radioactive material, xenon, was found in the air samples collected in South Korea,” said Lee Jae-yeong, a spokesman of the science ministry, who noted the equipment came from Sweden. “We, however, cannot say where specifically in the South the air samples were collected because it is confidential.”
Sweden also sent three specialists to the South on Oct. 11.
The analysis was completed in Sweden.
Xenon-133 is a radioactive isotope created in a nuclear explosion. It is a chemically inert gas, so it can stay in the air for days after a blast.
The science ministry also said the United States conducted its own tests and found radioactive material in an air sample. The ministry declined to elaborate further on the U.S. information.