Re: Infant Radionuclide Intake from Breast Feeding

[stabin@esper.com (Mike Stabin)]

>i know this sounds bizzare but one of our workers is breast feeding her 
>3 month old and asked what the potential intake would be for her infant 
>through breastfeeding. I remember a draft NRC publication on fetal 
>doses through placenta transfer-is there anything comparable to that 
>regarding breastfeeding ?
>
>Not kidding !
>

As Chris noted (sorry I am slow in responding - home computer has been in
the shop this week) - we have bunches of information on excretion of
radionuclides in breast milk, mostly from the nuclear medicine perspective.
There is certainly some crossover to nuclear power - iodines, xenons.  From
what I can tell, most radiopharmaceuticals that have been administered to
nursing women show up to one degree or another in the breast milk - the
pathway does not seem to be nearly as discriminatory as placental crossover.
We are not entirely clear on the mechanisms; we know that fat-soluble
substances may appear in milk to a good degree, but don't know yet why many
others do.  But I can share what I have.  I will e-mail you directly when I
get back to work Tuesday.  We are working with the NRC to publish some
guidance on this, again, from the pharmaceutical angle.  I did just finish
work with someone on an analysis of the contribution of short-lived nuclides
to mother and infant thyroid and mother's breasts for nursing women in the
Chernobyl area, with comparison to I-131.  I can share some of that also,
with anyone who may be interested.  E-mail me directly at stabinm@orau.gov.

Mike Stabin
Radiation Internal Dose
  Information Center
Oak Ridge, TN
423-576-3449  ph
423-576-8673  fax 
stabinm@orau.gov
http://www.orau.gov/ehsd/ridic.htm