Roads near Krasnogorskiy, via Google

In 2013 reports of a strange affliction began emerging from the remote towns of Kalachi and Krasnogorskiy in Kazakhstan; people were randomly falling asleep — sometimes while walking — only to wake up two to six days later with memory loss. Others experienced vivid hallucinations and short-term blackouts. No one was exempt from the mysterious illness; it affected young and old, and even, in one case, a cat. But on July 10 Kazakhstan’s Deputy Prime Minister Berdybek Saparbayev announced that scientists had discovered the cause: a form of carbon monoxide poisoning from a nearby shuttered Soviet-era uranium mine. But in the days that have followed the announcement, skepticism has risen — are the mines really sending residents into a deep sleep?

kazakhstan, kalachi, sleeping illness, carbon monoxide, uranium mine, hallucinations, krasnogorskiyCzech uranium mine, via Shutterstock

The symptoms displayed by the residents of Kalachi and Krasnogorskiy are bizarre to say the least. Last year the Siberian Times detailed a number of cases of the illness, in the case of Lyubov Belkova she keeled over while working at a market stall:

“Other women rushed to her asking what was going on, and then rapidly called an ambulance. The doctor thought she had suffered a stroke, and yet – two months later, a woman working alongside Lubov at the market fell asleep in identical fashion. Then Lyubov Belkova dozed off again. Sooner or later, all five women who were selling things at the small market on the road from Krasnogorsk to Kalachi fell asleep in the same way.

So did their security guard. By the end of it, as journalist Uliana Skoibeda recounted in Komsomolskaya Pravda, pensioner Lyubov Belkova slept in this way seven times, her daughter Natalia Mikhel twice and her 15 year old granddaughter Diana once.”

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The announcement from Deputy Prime Minister Saparbayev may have brought a sense of relief to the inhabitants of the two towns. As reported by The Astanza Times, Saparbayev told press that experts from the Institute of Radiation and Ecology and the Institute of Hygiene and Occupational Diseases, as well as the Institute of Nuclear Physics took samples from Kalachi and sent them to Moscow and Prague. The results came back, and the verdict was carbon monoxide poisoning. The next step? To relocate the several hundred residents of Kalachi and Krasnogorsky away from the suspect uranium mine.

But as quickly as the relief of an explanation came, so did skepticism. Claude Piantadosi, a pulmonologist at Duke University Medical Center told Sarah Zhang at Wired, that “The symptoms fit,” carbon monoxide binds the blood with 200 times the strength of oxygen, and with carbon monoxide in the air, the brain could be deprived of oxygen and subsequently shut down. But, Piantadosi continued “the symptoms are not specific, and that’s the problem.”

Indeed, why did some hallucinate and not others? Why were some affected and not others? Why was everyone not affected at the same time? Moreover, Zhang asks “The gas is indeed a problem in coal mines—it’s what the proverbial canary dies from—but carbon monoxide is the byproduct of combustion. The uranium mine next to the two villages was inactive. So what was carbon monoxide doing in there?”

It appears that the mystery is far from solved, but in the mean time, with residents located, hopefully they will be safe from further sickness.

+ Read Sarah Zhang’s full piece at Wired