Child leukaemia cases linked to gamma rays

 

Natural gamma rays may be responsible for around 40 cases of childhood leukaemia in the UK each year, research suggests.

Scientists found a small but significant link between the risk of the disease and exposure to gamma radiation from environmental sources.

Higher levels of gamma radiation were associated with a greater likelihood of children developing leukaemia.

The findings contradict the widely held belief that very low radiation doses have little or no effect on cancer rates.

They follow separate results published last week suggesting that low dose X-rays from a type of hospital scan can triple the chances of children developing leukaemia or brain cancer.

Gamma rays are essentially a highly penetrating form of invisible light that form part of the natural background radiation everyone is exposed to.

The main sources of natural gamma rays are radioactive isotopes, or atomic variants, of uranium, thorium and potassium. These can be found in the soil, rocks, drinking water and even building materials. Another source is cosmic radiation from outer space.

Study leader Dr Gerald Kendall, from the Childhood Cancer Research Group at Oxford University, said: "We found a statistically significant correlation between natural gamma-rays and childhood leukaemia.

"What is new in our findings is the direct demonstration that there are radiation effects at these very low doses and dose-rates.

"In terms of preventing childhood cancers caused by natural gamma-rays, there's not a lot you can do.

"We have estimated that about 15% of the 500 or so cases of childhood leukaemia which occur annually in the UK are due to natural background radiation.

"Natural gamma-rays account for about half the dose (of background radiation) reaching children's bone marrow from all sources. So they account for approaching 40 childhood leukaemias a year."

Natural gamma ray dose rate varied in different parts of the UK, said the researchers writing in the journal Leukaemia.

The highest average exposure of 120 nanograys per hour (nGy/hr) was found in South Yorkshire, Cornwall, the Isles of Scilly and the Scottish Borders.

Powys in mid-Wales, Dorset and Wiltshire, had the lowest measured rate of 70 nGy/hr.

The study is the largest ever conducted on links between childhood cancer and background radiation.

Dr Kendall's team analysed tens of thousands of cases from the National Registry of Childhood Tumours, a complete record of UK childhood cancers.

The scientists looked at radiation exposures for almost 27,500 children diagnosed with cancer between 1980 and 2006, including more than 9,000 with leukaemia. These were compared with exposures for almost 37,000 cancer free children.

Cumulative gamma radiation exposures from birth to diagnosis were estimated for different regions.

The researchers found a 12% increase in the risk of childhood leukaemia for every millisievert of natural gamma rays entering the bone marrow. Millisieverts are used to measure radiation absorption by biological tissue.

No significant associations were discovered between natural gamma rays and other childhood cancers. Nor was a link found between any kind of cancer and levels of radon, a radioactive gas produced by certain rocks.

Co-author Professor Richard Wakeford, from the University of Manchester, said: "Radiation protection measures assume that even low doses of radiation pose some, albeit small, risk of cancer.

"Naturally occurring gamma-rays provide an ever-present, very low-level source of exposure to radiation, but this very large epidemiological study suggests that even at these very low levels there is a very small risk to health."

Last week another team of British-led scientists reported a tripling of leukaemia and brain cancer risk in children linked to CT (computed tomography) head scans.

The research, published in The Lancet medical journal, led to calls for greater efforts to ensure use of the X-ray scans is justified.

PA

Voices
Homeless Veterans charity auction: Cook with Angela Hartnett and Neil Borthwick at Merchants Tavern
charity appealTime is running out to secure your favourite lot as our auction closes at 2pm tomorrow
Arts and Entertainment
J Jefferson Farjeon at home in 1953
booksBooksellers say readers are turning away from modern thrillers and back to golden age of crime writing
Sport
Amir Khan is engaged in a broader battle than attempting to win a fight with Floyd Mayweather
boxing Exclusive: Amir Khan reveals plans to travel to Pakistan
News
Stacey Dooley was the only woman to be nominated in last month’s Grierson awards
mediaClare Balding and Davina McCall among those overlooked for Grierson awards
PROMOTED VIDEO
Life and Style
ebookNow available in paperback
Life and Style
ebooksA superb mix of recipes serving up the freshest of local produce in a delicious range of styles
Voices
Joseph Kynaston Reeves arguing with Russell Brand outside the RBS’s London offices on Friday
voicesDJ Taylor: The great tradition of St Paul and Zola reached its nadir with a worker's rant to Russell Brand
News
Twitchers see things differently, depending on their gender
scienceNew study shows that birdwatching men have a lot in common with their feathered friends...
News
i100
Arts and Entertainment
Caroline Flack became the tenth winner of Strictly Come Dancing
tvReview: 'Absolutely phenomenal' Xtra Factor presenter wins Strictly Come Dancing final
Life and Style
A still from the 1939 film version of Margaret Mitchell's 'Gone with the Wind'
life
News
Xander van der Burgt, at the Royal Botanic Gardens, Kew
scienceA Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there
Arts and Entertainment
British actor Idris Elba is also a DJ and rapper who played Ibiza last summer
film
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    Recruitment Genius: Finance Director

    £65000 - £80000 per annum: Recruitment Genius: Finance Director required to jo...

    Recruitment Genius: Medico-Legal Assistant

    £15000 - £25000 per annum: Recruitment Genius: This is a unique opportunity fo...

    Ashdown Group: (PHP / Python) - Global Media firm

    £50000 per annum + 26 days holiday,pension: Ashdown Group: A highly successful...

    The Jenrick Group: Quality Inspector

    £27000 per annum + pension + holidays: The Jenrick Group: A Quality Technician...

    Day In a Page

    The week Hollywood got scared and had to grow up a bit

    The week Hollywood got scared and had to grow up a bit

    Sony suffered a chorus of disapproval after it withdrew 'The Interview', but it's not too late for it to take a stand, says Joan Smith
    From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?

    Panto dames: before and after

    From Widow Twankey to Mother Goose, how do the men who play panto dames get themselves ready for the performance of a lifetime?
    Thirties murder mystery novel is surprise runaway Christmas hit

    Thirties murder mystery novel is surprise runaway Christmas hit

    Booksellers say readers are turning away from dark modern thrillers and back to the golden age of crime writing
    Anne-Marie Huby: 'Charities deserve the best,' says founder of JustGiving

    Anne-Marie Huby: 'Charities deserve the best'

    Ten million of us have used the JustGiving website to donate to good causes. Its co-founder says that being dynamic is as important as being kind
    The botanist who hunts for giant trees at Kew Gardens

    The man who hunts giants

    A Kew Gardens botanist has found 25 new large tree species - and he's sure there are more out there
    The 12 ways of Christmas: Spare a thought for those who will be working to keep others safe during the festive season

    The 12 ways of Christmas

    We speak to a dozen people who will be working to keep others safe, happy and healthy over the holidays
    Birdwatching men have a lot in common with their feathered friends, new study shows

    The male exhibits strange behaviour

    A new study shows that birdwatching men have a lot in common with their feathered friends...
    Diaries of Evelyn Waugh, Virginia Woolf and Noël Coward reveal how they coped with the December blues

    Famous diaries: Christmas week in history

    Noël Coward parties into the night, Alan Clark bemoans the cost of servants, Evelyn Waugh ponders his drinking…
    From noble to narky, the fall of the open letter

    From noble to narky, the fall of the open letter

    The great tradition of St Paul and Zola reached its nadir with a hungry worker's rant to Russell Brand, says DJ Taylor
    A Christmas ghost story by Alison Moore: A prodigal daughter has a breakthrough

    A Christmas ghost story by Alison Moore

    The story was published earlier this month in 'Poor Souls' Light: Seven Curious Tales'
    Marian Keyes: The author on her pre-approved Christmas, true love's parking implications and living in the moment

    Marian Keyes

    The author on her pre-approved Christmas, true love's parking implications and living in the moment
    Bill Granger recipes: Our chef creates an Italian-inspired fish feast for Christmas Eve

    Bill Granger's Christmas Eve fish feast

    Bill's Italian friends introduced him to the Roman Catholic custom of a lavish fish supper on Christmas Eve. Here, he gives the tradition his own spin…
    Liverpool vs Arsenal: Brendan Rodgers is fighting for his reputation

    Rodgers fights for his reputation

    Liverpool manager tries to stay on his feet despite waves of criticism
    Amir Khan: 'The Taliban can threaten me but I must speak out... innocent kids, killed over nothing. It’s sick in the mind'

    Amir Khan attacks the Taliban

    'They can threaten me but I must speak out... innocent kids, killed over nothing. It’s sick in the mind'
    Michael Calvin: Sepp Blatter is my man of the year in sport. Bring on 2015, quick

    Michael Calvin's Last Word

    Sepp Blatter is my man of the year in sport. Bring on 2015, quick