Average Dose Rate of 1.11x108 Bq 131I in Thyroid

AI Thread Summary
The discussion centers on calculating the average dose rate of 131I in the thyroid after a patient receives an injection of 1.11×10^8 Bq, with 30% directed to a 20 g thyroid mass. The formula used is D=1.60×10–10AE Gy s–1, where A is calculated as 1.665×10^6 Bq/g. The energy value used is 0.192 MeV, leading to a dose rate of 51 μGy/s. A key point of confusion arises regarding the missing factor of 10^6 in the calculation of A, which affects the final result. Clarification is sought on this calculation error.
xamy
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Homework Statement


A patient receives an injection of 1.11×108 Bq of 131I,30% of which goes to the thyroid, having a mass of 20 g.What is the average dose rate in the organ?


Homework Equations


D=1.60×10–10AE Gy s–1

The Attempt at a Solution

A=(1.11x108x(30/100))/20=1.665x106Bqg-1

E=0.192Mev

=1.60x10-10 (1.665)(0.192Mev)

= 51μGy s–1

This is my solution. Can anyone point out the mistake here.
 
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xamy said:
=1.60x10-10 (1.665)(0.192Mev)

What happened to the factor 10^6 you had in calculating A?
 

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