The Health Protection Agency has, belatedly, started to give some quantitative estimates of the radiation doses detected in the urine samples of the people who are feared to have been slightly contaminated with Polonium-210, following the poisoning of Alexander Litvinenko.
Why could these figures not have been released in November, when they could have reduced the amount of "radioactive dirty bomb" hype and media spin ?
There is a bit more background explanation in their Dose Assessment (.pdf) document, but the Health Protection Agency still gives no indication of the amount of Polonium-210 that Alexander Litvinenko was was killed with, or how much may have been smuggled into the United Kingdom.
There is no indication as to how Alexander Litvinenko was poisoned i.e. by drink, by food, by inhalation or injection etc.
There are still no estimates of how much Polonium-210 may still be in the hotels, bars, restaurants, aeroplanes and other vehicles etc, where traces have been detected.
The Analytical Procedure for testing the urine samples for 210Po (.pdf) seems to require at least a litre of urine per sample !
* 480 people had results ‘below reporting level' - below 30 millibecquerels (mBq) per day (natural levels of Po-210 in urine are typically in the range 5-15 mBq per day). It is therefore unlikely that any of these people had been exposed to Po-210
* 73 people had results above 30 mBq per day in their urine, but with a dose less than 1mSv indicating no public health risk, and no health concern to the individual, but probable contact with Po-210
* 30 people had results above 1 millisievert (mSv), but below 6mSv indicating no public health risk, and no health concern to the individual, but probable contact with Po-210
There are 583 results in categories 1, 2 and 3a and these are NOT of health concern.
* 13 people had results above 6mSv which are not significant enough to result in any illness in the short term and any increased risk in the long term is likely to be very small