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'Most radioactive man' Hisashi Ouchi was kept alive for 83 days after nuclear blast horror

The 1999 Tokaimura Nuclear Power Plant explosion was the worst nuclear accident in Japan for years - and the start of 83 days of living hell for technician Hisashi Ouchi who was caught in the huge uranium explosion.

As nuclear technician Hisashi Ouchi helped a colleague to pour litres of uranium in to a huge metal vat, he was blissfully unaware that these would be his final moments without pain.

Moments later a blue flash engulfed the room at the Tokaimura Nuclear Power Plant as the gloopy and dangerous mixture reached ‘critical point’, releasing neutron radiation and gamma-rays.

Ouchi, 35, was the worst affected by the unexpected blast as he had been draped across the tank.

He had been helping Masato Shinohara pour the radioactive liquid in to the vat, and colleague Yutaka Yokokawa had been working at a desk 4 metres away.

None of the men had been trained to perform such sensitive procedures, and it was later found that there was 16kg of uranium in the mixture, when the limit was 2.4kg.

What happened at 10:35am, 28 September 1999, would be the worst nuclear accident in Japan for years - and the start of eighty-three days of living hell for Ouchi.

Immediately after the explosion, he was falling in and out of consciousness, violently vomiting, and suffering from extreme burns. It is believed that he absorbed 17 Sieverts of radiation, the highest level any living human has been exposed to.

For context, eight is enough to kill you. Hiroshima and Nagasaki survivors were exposed to 0.5sv, and emergency workers who attended the Chernobyl disaster in Ukraine exposed to 0.25sv. But despite experiencing such huge levels of radiation, Ouchi did not die - at least not immediately.

He was rushed to University of Tokyo Hospital, where doctors were faced with a husk of man who was practically skin-less, had close to zero white blood cells, multiple organ failure and a destroyed immune system.

A team of the finest doctors in Japan and experts from around the world performed skin grafts, and pumped him full of fluids and donor blood, keeping him locked away in a special radiation ward.

According to local reports, he began bleeding from his eyeballs, prompting his wife to exclaim that he was “crying blood”.


The radiation blast obliterated his DNA, so doctors gave him stem cells donated by his sister in the hope that his body would use them to get stronger and help him recover.

It is hard to imagine the level of pain that Ouchi experienced in the weeks after the incident, and despite being pumped full of painkillers and put in to an induced coma at times, he was also reported to have screamed for mercy.

After just seven days of being trapped in this living death, he is reported to have screamed: “I can’t take it anymore! I am not a guinea pig!”

On the 59th day of his hospitalisation, his heart-stopped three times in 49 minutes, but on his family’s request he was resuscitated every time, damaging his brain and kidneys further.

His loved ones must have been desperate for the doctors’ medical interventions and experimental remedies to save poor Ouchi’s life, but after weeks on a life-support machine, his body finally gave up on December 21, 1999, due to multi-organ failure.

1 Comment

shyam kiran
shyam kiran
Dec 23, 2022

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