What secret report reveals about British nuclear weapons tests – veterans claimed they were harmed by the fallout
“The Ministry of Defence has always maintained that it never rained,” said Ken McGinley, founder of the British Nuclear Test Veterans Association (BNTVA). “I’m sorry, you’re liars … I was there!”
McGinley, who was a royal engineer, gave this interview in January 2024, shortly before his death, as part of our Oral History of British Nuclear Test Veterans project.
McGinley was present during the Grapple nuclear weapons test series, conducted by the UK on the central Pacific island of Kiritimati (also known as Christmas Island) in the late 1950s. At the time, this remote atoll was inhabited by 250 villagers as well as thousands of British servicemen.
For decades, many of those present during this and other above-ground British nuclear weapons tests have argued they were harmed by radioactive fallout. McGinley founded the BNTVA in 1983 to “gain recognition and restitution” for the veterans who took part in British and American nuclear tests and clean-ups between 1952 and 1965.
Rain became a key symbol in their argument as one of the only tangible signs of fallout taking place. The nuclear physicist Sir Joseph Rotblat described these alleged post-blast showers as “rainout”, a phenomenon whereby rain and mushroom clouds interact, leading to the contamination of rain droplets by harmful radionuclides.
In almost all cases, any link to subsequent health issues has been denied by the UK government because of lack of evidence of widespread radioactive contamination. However, a review of the evidence – written in 2014 by anonymous government scientists in response to freedom of information requests – was recently leaked by whistleblowers.
It reveals that post-blast radiation readings increased by a factor of up to seven on the island, compared with the normal background level. In our view, this would be more than enough to satisfy the “reasonable doubt” that tribunals require for veterans to receive a war pension due to illness or injury related to their service, as stated in the Naval, Military and Air Forces (Disablement and Death) Services Pension Order.
The top secret review, first revealed publicly by the Mirror newspaper on March 14 2026, also contains new evidence of radioactive contamination of fish in the island’s waters.
The repeated dismissal of veterans’ testimony in court cases and pension appeals caused stress and trauma for many. The majority died insisting they were not deceitful or forgetful – and that it did indeed rain while they were living on Kiritimati.
‘Factually inaccurate’
Kiritimati was monitored for fallout by the Ministry of Defence (MoD) after each detonation over the island – the largest of which, Grapple Y, was 200 times more powerful than the bomb dropped on Hiroshima.
In 1993, environmental monitoring data was collated into a report by a team at the MoD’s Atomic Weapons Establishment (AWE). Known as the Clare report, this informed the UK’s official position on fallout: namely, that none occurred over populated areas and that veterans would need to prove otherwise to secure redress.
However, the 2014 review of fallout data concluded the Clare report was “incomplete and, in some cases, factually inaccurate”.
Despite this review being passed on to the MoD, however, it was kept secret for more than a decade. Following its release, the legal implications could be gamechanging. According to the 2014 review: “The instrument readings could potentially be used to challenge the validity of statements made by MoD and UK government regarding … fallout on Christmas Island.”
In a recent House of Commons debate on the issue, the UK minister for veterans and people, Louise Sandher-Jones, confirmed her commitment “to the nuclear test veterans and their fight for transparency … They have had a very long fight, and I really recognise how difficult it has been for them, and I want them to understand that I am committed to them.”
What Merlin reveals
Behind the scenes, the release of newly declassified archival material in the publicly accessible Merlin database has added to calls for government accountability about the nuclear tests.
Compiled by the treasury solicitor during a class action against the MoD between 2009 and 2012, the database was stored at AWE until the journalist and author Susie Boniface discovered it held information about the medical monitoring of servicemen and Indigenous people. Her work led to its release in 2025.
Holding over 28,000 files, Merlin was commissioned by the MoD in response to the compensation claims made by almost 1,000 veterans from 2009. Its contents include official reports and communications, photographs, maps, safety guidelines and health monitoring information. Video footage includes the Grapple X test in November 1957.
A University of Liverpool team based in The Centre for People’s Justice and the Department of History is working with Boniface and campaign group Labrats International to catalogue and analyse the contents of Merlin – combining it with other sources, including personal testimony. Recently released files indicate nuclear fallout in the island’s ground sediment and rainwater, and heightened radioactivity in its clams.
Evidence has also emerged of radioactive waste being dropped from aeroplanes into the sea off Queensland in 1958 and 1959. Although dumping radioactive waste was surprisingly common during the cold war, this revelation raises questions about how risk and danger was understood and managed during Britain’s nuclear test programme.
The files also show workers without protective clothing around a plutonium pit at Maralinga in South Australia, site of seven British atmospheric nuclear tests in 1956-57.
The Merlin releases have galvanised claims that not so long ago may have been interpreted as conjecture. The recent releases suggest that servicemen and islanders were exposed to radioactive fallout – not just from rain showers, but from the fish they ate and the water they drank.
While a causal link with subsequent health conditions would be hard to prove, we believe it is time for the UK government to get behind a public inquiry into the full impact of Britain’s nuclear weapons testing programme.
Christopher Hill was Principal Investigator of 'An Oral History of British Nuclear Test Veterans', a two-year project funded by the UK Office for Veterans' Affairs.
Jonathan Hogg receives funding from Research England’s Policy Support Fund to support research into the Merlin database. He was Co-Investigator on 'An Oral History of British Nuclear Test Veterans', a two-year project funded by the UK Office for Veterans' Affairs. The final report can be viewed here: https://www.liverpool.ac.uk/humanities-and-social-sciences/research/projects/nuclear-test-veterans/