Banana equivalent dose

[TransformX]

http://en.wikipedia.org/wiki/Banana_equivalent_dose

[Brian Ellis]

Silly article. Ra in Brazil nuts emits essentially alpha radiation and would be present in such minute quantities as to be negligible. Potassium 40 emits beta radiation but comprises only 0.0117% of free potassium in the salts in a banana. You cannot compare the physiological effects of alpha and beta particles, like that.

Don't know why you put this in science and military, as the article is neither scientific nor military.

[Dr Mordrid]

It belongs here because it's a scientific curiosity that's actually used in the really-real world outside of lofty intrrnational confernces. We used BED in radiomedicine all the time, usually to compare relative doses for patients & other lay people but also in our internal conversations.

Normally potassium-40 is rare in soils, but mined potassium used for fertilization often has it in higher than normal levels because those deposits are often found in strata adjacent to those containing uranium deposits. As such you have to deal with decay products from it and any other radioisotopes that may be present. When plants absorb these fertilizers the isotopes get concentrated in its fruit and leaves at higher than background levels.

In the case of banana plants - they concentrate a lot of potassium in their fruit, ~467 mg per, which is why people with low potassium levels are often advised to eat them. The K40 goes along for the ride and also gets concentrated. Fortunately most potassium doesn't stay in the body too long, so mutagenic effects are minimal.

BED: 1 per 150g banana

- amounting to about 520 picocuries worth of both electrons and positrons. K40 can also absorb electrons, emitting an electron antineutrino. This makes it one of the few isotopes that exhibits all 3 forms of beta decay.