When Robert Fleming watched one of the world's most powerful weapons detonate 60 years ago, little did he know of the lasting impact it would have on future generations.

Eastern Daily Press: The Christmas Island bomb test. Photo: John Greenacre.The Christmas Island bomb test. Photo: John Greenacre.

Aged just 24, the RAF serviceman was stationed on an island in the Pacific Ocean when Britain tested its first megaton-class thermonuclear bomb.

Now aged 83, he believes his prolonged exposure to radiation in the following weeks has led to deformities in three generations of his family.

He said his grandson and great grandson suffered problems with their genitals, while his youngest daughter was born with extra knuckles.

In total, he said eight members of his family - mostly grandchildren and great grandchildren - were born with severe health defects.

Eastern Daily Press: Derek Chappell, nuclear test veteran. Photo: Luke PowellDerek Chappell, nuclear test veteran. Photo: Luke Powell (Image: Archant)

Mr Fleming is one of several veterans from Norfolk who claim their ill health is linked to the nuclear bomb tests they witnessed in the 1950s.

Many have now shared their stories to mark the 60th anniversary of the UK's first true hydrogen bomb test on November 8, 1957, codenamed Grapple X.

Around 22,000 men, many on National Service, were ordered to Australia and Christmas Island in the South Pacific from 1952 to witness the explosion of dozens of atomic and hydrogen bombs.

In the following years, many reported increased cases of blood, thyroid and tongue cancers, as well as rare blood disorders.

Eastern Daily Press: A scroll given to Barry Middleton who was aboard HMS Narvik durinng the tests. Photo: Luke PowellA scroll given to Barry Middleton who was aboard HMS Narvik durinng the tests. Photo: Luke Powell (Image: Archant)

The Ministry of Defence (MoD) has always denied blame.

Mr Fleming, who lives in Downham Market, was on a beach on Christmas Island during the Grapple X test.

He was one of around 3,000 servicemen stationed within a 23-mile radius of the planned detonation point.

The men, who were from the RAF, Navy and Army, were given no protective clothing or individual dosimeters to measure radiation levels.

Eastern Daily Press: An aircraft spraying the island with DDT. Photo: Ron NealAn aircraft spraying the island with DDT. Photo: Ron Neal (Image: Archant)

Instead, they were told to sit with their backs to the blast and cover their eyes.

Mr Fleming, who also took part in the Grapple Y test months later, believed radioactive fallout contaminated water sources on the island.

He said: 'We used to swim in the sea and in the lagoons, shower in sea water and eat fish that were caught there.

'It was all contaminated, but I didn't think anything of it at the time.'

Eastern Daily Press: David Freeman, who witnessed the Christmas Island nuclear bomb test. Pictured with an illustrated memorial poster of the event. Picture: ANTONY KELLYDavid Freeman, who witnessed the Christmas Island nuclear bomb test. Pictured with an illustrated memorial poster of the event. Picture: ANTONY KELLY (Image: Archant Norfolk 2017)

Mr Fleming said he avoided any major health issues until his later years.

Instead, it was his youngest daughter who was the first to show signs of ill-health. She was born with extra knuckles on both hands, and lost her teeth by the time she was 30.

His wife, Jean, 79, said: 'It was frightening. When one of our children fell pregnant we would just think 'please god let them be alright'.

'But they just started getting more and more wrong with them.'

Mrs Fleming said one grandson was born with his knee caps out of place, while another suffered from a condition affecting his genitals.

Their great grandchildren, meanwhile, suffer from a wide range of health defects, including having no enamel on their teeth, hypermobility, eyesight problems, and genital issues.

Fellow Grapple X veteran Derek Chappell, who lives in Swaffham, said he developed a rare blood disorder decades after the tests.

Known as polycythaemia vera, the condition causes too many red blood cells to be produced in the bone marrow.

Cancer Research UK said exposure to radiation can increase the risk of developing the disorder.

Mr Chappell, who was 20 when he witnessed the explosion, had been tasked with recording the blast from the back of an old signals truck.

The 81-year-old said: 'There has to be justice for what has happened, but of course everyone who was involved is now getting on a bit.'

Earlier this year, London's Brunel University announced it was launching a study looking at possible genetic damage caused to nuclear test veterans.

Blood samples were taken from 50 men present at explosions in Christmas Island and South Australia in the 1950s and 1960s.

Samples will also be taken from the men's wives and children to see if any genetic damage has been passed on.

The UK remains the only nuclear power to deny recognition to its bomb test veterans. France, Russia, the USA, China, Australia, New Zealand, Fiji and even the Isle of Man all admit their citizens were harmed by radiation and pay some form of compensation.

My gums started to bleed and my teeth fell out

Veteran David Freeman said his gums started to bleed in the weeks after the Grapple X test.

And within a year, the 78-year-old, from Thorpe St Andrew, said his teeth started to fall out.

But, much like fellow test veteran Robert Fleming, Mr Freeman said it was not just himself who has suffered.

He claimed his daughter also started to lose her teeth, while one grandchild was born deaf, and another only had one kidney.

Mr Freeman, meanwhile, has suffered bowel and bladder cancer.

'When you are exposed to something in the megaton range, you are bound to be affected by radiation of some sort,' he said.

'We must have had the lot, because when it rained on the island, we were walking through six to seven inches of water.'

He also claimed there was an instance on Christmas Island where discoloured rain fell from the sky - a claim backed up by other veterans.

MoD response

The MoD said it was 'grateful' to those who participated in the British nuclear testing programme.

But it added: 'Other than what we have paid out for, we have seen no valid evidence to link these tests to ill health.'

The MoD said there was no published peer-reviewed evidence of excess illness or mortality among nuclear test veterans as a group, which could be linked to their participation in the tests, and claimed there were 'state-of-the-art' procedures in place to ensure the health and safety of those taking part.

The MoD said a possible increase in leukaemia in the first 25 years had been identified. As a result, awards were made under the War Pensions Scheme.

Nuclear test veterans took their case to the Supreme Court but in March 2012 seven justices handed down a majority decision in favour of the MoD.

It said: 'All seven justices recognised the veterans would face great difficulty proving a causal link between illnesses suffered and attendance at the tests.'

The nuclear tests

Operation Grapple was the code-name given to a series of nuclear weapon tests carried out by the British in the late 1950s.

Between 1957 and 1958, nine hydrogen bombs were detonated at Malden Island and Christmas Island.

The first series of Grapple tests at Malden Island failed to reach the predicted destructive yield.

But months later on November 8, the Grapple X thermonuclear bomb was dropped by a Valiant bomber five miles off the south east point of Christmas Island.

It detonated after 52 seconds of freefall and created Britain's first megaton-class explosion, with a yield of 1.8 megatons, 100 times more powerful than the bomb dropped on Hiroshima.

The following test, Grapple Y, was in April 1958 and became the most powerful nuclear weapon ever tested by the UK, with a yield of around three megatons.

In 1958, a moratorium came into effect and Britain never resumed atmospheric testing.

DDT spray over Christmas Island

Radioactive fallout was not the only potential health risk to those stationed on Christmas Island.

Test veteran Gordon Wilcox, 80, from Attleborough, said aircraft would regularly spray the island with the insecticide DDT.

The substance was banned by most developed countries in the 1970s and 1980s.

Mr Wilcox, who is chairman of the Anglia branch of the British Nuclear Test Veterans Association (BNTVA), said: 'There is credible anecdotal evidence to the effect that many individuals would eat their meals in the open air to escape the heat in the mess tents.

'Consequently, they and their food would be invariably exposed to the spray.'

Tests veteran Ron Neal, who attended the anniversary event in Norwich on Wednesday, managed to photograph an aircraft spraying the chemical.

The BNTVA said tests found that DDT is of low hazard and low toxicity to man