One Becquerel a gramme is a safe level fixed by the Malaysian government through the Atomic Energy Licensing Board (AELB).

Their accomplishments led the Royal Swedish Academy of Sciences to award the Curies, jointly with Henri Becquerel , the Nobel Prize in physics for 1903.

One of these models anticipates a max concentration by mid-2015 of up to 27 becquerels per cubic metre of water; the other suggests no more than about two becquerels per cubic metre of water.( ANI )

A record high 140,000 becquerels per litre of beta radiation was detected, compared with 59,000 becquerels on the previous day, the operator of the Fukushima Daiichi Nuclear Power Station said.

Early researchers such as Pierre and Marie Curie, Edward Rutherford and Becquerel eventually found that many other chemical elements besides uranium have radioactive isotopes.

"While the samples are well below the 500 becquerel per kilogram limit set by the authorities, the contaminated seafood still represents a health risk, especially to pregnant women and children, and it is being distributed over a wide area," said Wakao Hanaoka, Greenpeace Japan oceans campaigner.

Becquerel had noted an accidental burn on his skin as the result of carrying an ampoule of radium in his pocket and in 1901 Pierre Curie confirmed this by deliberately producing a burn on his own arm with this material.

Becquerel Watson, 11, from Wattsville, near Caerphilly, participated with her mum Kathryn, 39, and grandmother Val Tucker, 62.

Her husband soon joined in her scientific investigations into the natural radioactivity discovered by another French scientist, Antoine Henri Becquerel .

The Curies began researching radioactive elements after Henri Becquerel discovered, by chance, radioactive uranium.