Licence, page-43

1 becquerel

(apologies to Dr Looi, not trying to do your job, mate)

Seeing activities written down in becquerels often gives the impression that such activities are exceptionally high and thus very dangerous. This is mainly due to the small value of a Becquerel, and substances are rarely that dangerous. The Becquerel is like the Deutschmark used by the Weimar republic in the 1920s when a wheelbarrow full of which was needed to buy a croissant.
http://www.radioactivity.eu.com/site/pages/Activity_Doses.htm

Becquerel or Bq : the unit of activity for a radioactive source

The Becquerel: a very small unit…:
The becquerel, the commonly-used unit of activity, corresponds to a decay rate of one nucleus per second. This unit on the scale of the atom is so small (and therefore ill-adapted to describe the activities of most radioactive substances we deal with) that multiples of becquerels are frequently used: kilo (thousands), mega (millions), giga (billions) and terabecquerels (thousands of billions), etc. The diagram above shows the range of activities different substances – from a litre of water up to the spent fuel extracted from the core of nuclear reactors – can have.

http://www.radioactivity.eu.com/site/pages/Activity_Doses.htm



Food is naturally radioactive !
The food we eat is lightly radioactive, as we can see from the levels measured in various different foodstuffs. Activities of several hundred becquerels (Bq) per kilogram or litre may seem high, but the bequerel is a very small unit : the body of a 70kg man has a natural activity of 8000 Bq.
IN2P3
The spring water that we drink is also radioactive. Before bursting out of the ground it has dissolved various mineral salts from its underground path, including a large variety of radioisotopes. The most radioactive waters come from areas with granite or volcanic rocks, where uranium, thorium and their descendants are present in the ground. The exposure levels here, however, vary wildly.



Radioactivity of spring water:
Water contains small amounts of radioactivity owing to the radioactive rocks it flows over and dissolves. As an example, the above graph displays the annual dose one would receive from a granitic spring water, supposing that one drinks a litre of this water every day for a whole year. This study shows that the contribution to the annual dose would be a fraction of millisievert (mSv) to be compared to the 2,4 mSv average dose due to natural radioactiviry.
IN2P3
In the United States, the average activity of household drinking water is of 18.5 Bq/litre, which corresponds to a truly inconsequential risk given the tiny value of the becquerel.

http://www.radioactivity.eu.com/site/pages/Radioactivity_food.htm

Muppets !!!!!