No additional signs of radiation from last week’s North Korean nuclear test have so far been detected by China’s environmental ministry, according to local media.

A report from Xinhua news said none of the 36 monitoring stations near the Chinese-DPRK border had detected any radioactive pollution, with all readings within the normal range.

Beijing’s Ministry of Environmental Protection is currently conducting tests using automated equipment and sending staff to collect samples.

“(Our detectors measure) radiation dosage rate using sodium iodide crystals. This method is currently the most accurate and stable,” deputy head of Jilin Province’s Radiation Environment Monitoring Station said in comments carried by Xinhua.

The Korea Institute of Nuclear Safety (KINS) has also been conducting tests, and last week announced it had detected traces of Xenon 133, one of the isotopes released after a nuclear explosion.

Further analysis however has proved inconclusive, with KINS telling reporters in Seoul yesterday that there had been no subsequent detection of Xenon.

“As the result of whole analysis, it’s impossible to judge what kind of nuclear test took place. For the first, second and third analyses the minimum of xenon was detected but for the fourth and fifth, it was not,” KINS told reporters in Seoul yesterday.

RADIOACTIVE NEEDLES IN A HAYSTACK

A report from the International Strategic and Security Studies Programme (ISSSP) at India’s Bangalore Program published after the January 6 explosion details how different nuclear devices can be identified the elements produced after the explosion.

While North Korea claimed last week’s test was a small hydrogen device, many experts have concluded the lack of a corresponding increase in the strength of the seismic signature indicates the test was more similar to North Korea’s previous detonations.

“While expert opinion around the world seems to be veering towards the view that the 2016 test was indeed that of a fission device, from a purely technical point of view one cannot rule out the possibility that the test was that of a small thermonuclear device,” the report reads.

Thermonuclear devices like hydrogen bombs however should emit a different radioactive signature, which could be used to identify the weapon.

According to the ISSSP report, researchers will currently be looking for one of four different types of Xenon to confirm if the detonation was nuclear, though elevated levels of Argon gas would be indicative of a thermonuclear blast.

“In order to establish or disprove the North Korean claim of having tested a thermonuclear device, Argon-37 has to be detected by the international radionuclide monitoring stations,” the report reads.

The authors also warn however that the detection of various isotopes is by no means a guarantee. Without onsite inspections, the detection process is dependent upon how weather, and how well the North Koreans sealed the test site.

Other residual gases like tritium or deuterium would also show if North Korea tested a hydrogen bomb, though these are less likely to travel far from test site.

“Prospects for detection of the thermonuclear nature of a test by sampling atmospheric air for these at a distance appear low,” the authors note.

All in all, the authors are not optimistic conclusive evidence of the nature of North Korea’s most recent test will come from atmospheric testing.

“It is possible that if the test is completely contained there will no venting taking place. In such a situation it is unlikely that radionuclide monitoring will provide convincing evidence that North Korea had indeed tested a thermonuclear or a boosted fission device.”

Additional reporting by Hyunbi Park

Featured Image: 2012-0115 by VGB.Studios on 2012-05-24 17:17:49