Inside the radioactive island with mutant sharks that was used to test nuclear bombs

Mutant sharks. White sand laced with plutonium. Water tainted with strontium. Hub cap-sized hermit crabs eating coconuts containing caesium. A dome ‘coffin’ crammed with radioactive material in plastic bags.

The Marshall Islands, a ring of coral reefs in the middle of the Pacific Ocean, looks like the perfect place to throw on a floppy sun hat and read a book below swaying palm trees.

But in the 1940s and ’50s, the US used two of the far-flung atolls, Bikini and Enewetak, to test out 67 nuclear bombs.

One was 1,000 times more powerful than the Hiroshima bomb, according to Hibakusha Worldwide, which tracks nuclear incidents.

This was part of Operation Crossroad, an atomic testing programme that came out of the anxiety of the Cold War.

With 52,000 Marshallese people calling the islands home at the time, the 20 islands are the remnants of ancient volcanoes halfway between Hawaii and Australia.

Yet entire islands were vaporized and craters gouged into its shallow lagoons, forcing hundreds of people out of their homes, never to return.

Bikini Atoll now has such a reputation for groovy wildlife it inspired the setting of Spongebob Squarepants.

While the islands are unlikely home to talking sponges, the radiation that lingers in its waters is impacting the wildlife.

Nurse sharks with just one dorsal fin swim around the Bikini Atoll and car-sized coral grows along the seafloor.

‘Popular belief is that radiation causes mutations, and you know what, it’s true,’ Steve Palumbi, a professor of marine sciences also at Stanford, told The Sun.

Even low levels of radiation can cause genetic mutations. Caesium, strontium and other radioactive isotopes break apart DNA, compressing thousands of years of evolution into a few decades in what one paper once described as ‘unnatural selection‘.

Marine life is on the rebound in Bikini. ‘The fact there is life there and the life there is trying to come back from the most violent thing we’ve ever done to it is pretty hopeful,’ said Steve Palumbi, a professor in marine sciences at Stamford University.

The water, though, remains undrinkable and sealife and plants cannot be eaten due to the radioactive water and soil.

People living on nearby islands, now part of the Republic of the Marshall Islands, during and after the testing show a higher risk of developing cancer – not one of the top two causes of death – and birth defects.

The list of woes for the Marshallese does not end there, with rising sea levels fuelled by climate change slowly swallowing up the habitable atolls.

The largest nuclear detonation was the hydrogen bomb Castle Bravo, fired on March 1, 1954, in Bikini. As the mushroom-shaped clast cast a shadow over the island, the radioactive fallout and debris spewed well beyond the shorelines.

‘Traces of radioactive material were later found in parts of Japan, India, Australia, Europe, and the US,’ says the Atomic Heritage Foundation.

‘This was the worst radiological disaster in US history and caused worldwide backlash against atmospheric nuclear testing.’

Bikini, the colonial spelling of Pikinni, became so radioactive there’s little hope it’ll ever be habitable.

After the Limited Test Ban Treaty of 1963 put an end to atmospheric nuclear testing, this left American officials – and the islands’ displaced citizens – with one option: wait.

The Defence Department concluded in the ’70s that the soil was so contained with cesium-137 and strontium-90 – both taking about three decades to decay, called a half-life – that the best course of action was to just let it rot.

Plutonium-239, however, takes a little longer; 24,000 years. The US dumped 437 plastic bags filled with lumps of plutonium that had spewed after a bomb misfired into a 33-foot crater left behind in 1958 by a nuke on Runit Island.

That, and about 35 Olympic-sized swimming pools’ worth of radioactive soil and nuclear waste.

The crater was plugged up by a 350-foot-wide slab of concrete called the Rumit Dome, which locals call ‘The Tomb’, in the ’70s. The dome almost looks like something from a science fiction movie, surrounded by a tropical paradise.

And the dome is leaking. ‘The dome is a significant visible scar on the landscape,’ Ken Buesseler, a marine radioactivity expert at the Woods Hole Oceanographic Institution (WHOI), told Oceans magazine in 2020.

‘But it’s a relatively small source of radioactivity.’

Overall, more than half of the 167 original inhabitants of Bikini Atoll have died. Some started showing cancers related to radiation exposure in the 1960s, while people living downwind of the explosions suffered burns and low blood counts.

Several generations later, about 5,400 Bikinians are still living in exile. Some live on a lone Pacific island called Kili, roughly 400 miles from Bikini, and others from Honolulu to the ‘Wheat Capital’ of Oklahoma, Enid.

Bikini Atoll largely remains uninhabited, with a tiny caretaker team taking care of the island infrastructure and divers pop in from time to time.

Bikinians continue to fight, however. Lobbying the US Congress for money to redevelop and clean up the place they once called home.

Scientists are hopeful. Remediation efforts include sprinkling affected areas with potassium fertilizer which reduces how much cesium-137 seeps into locally grown crops. How radioactive the soil is has also been decreasing.

The Marshall Islands Program advises that, once resettlement finally begins, a radiation monitoring programme be set up.

‘In this way, the Kili-Bikini-Ejit Local Government and the people of Bikini can be assured that radiological conditions on the islands remain at or below applicable safety standards, and the United States Government can avoid mistakes of the past,’ the programme says.

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