My son (age 4, about 16kg) had to have a barium enema last year and I was wondering how much radiation he received. When I called the hospital they told me that he got 60 mGy amount of radiation, which (they said) was about 1/5 of the background radiation of 300 mGy we would get during a year in USA (California, low altitude). Is that correct?
When checking the Internet, I see that 1mGy=1mSv and the background radiation for a year listed online is ~3mSv. Do you think they told me the wrong units? Or the 60mGy is NOT the actual effective dose that he was exposed to.
This was not an easy answer to find! But I think I did find some information that will help you:
Pediatric radiation dose: http://radbandit.net/Dose_Factors.html
Patient Dose comparison: http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_xray
Dose Units Conversion table: http://www.civildefensemuseum.com/southrad/conversion.html
Compare mGy to mSv: http://hps.org/publicinformation/ate/q3142.html
According to the websites referenced above, your son probably received 7.2 to 8 mSv and the annual dose from natural occurring background radiation is 3 mSv. The hospital used the wrong units and might have meant micro instead of milli. mGy measures radation dose to any material, mSy is the measure of exposure to human tissue.
If your son did truly get 60 mSv instead of 60 micro-sieverts, that would be extremely excessive. I'd be inclined to use the information in the charts above.
Hope this helps,
Santa Barbara Extremity MRI