[ RadSafe ] C-14 uptake in breast milk

[James Talty]

Dear group,
I have a young lady who will be using C-14 labeled amino acids (100s of mics/month) compounds and is also nursing a new baby (~2 months). Although she is very skilled at handling radioactive materials (+10 yrs experience), she is worried that some of the C-14 may be passed to her new baby while nursing. I've searched the literature but can't find much information that helps. I did find one article that estimates an uptake of 0.001%, however, the study involved rats. I believe the probability of actual uptake is extremely low and would not have any impact on the baby, however, she wants more proof and reassurance than I can currently provide. I would appreciate any help.
Thank You,
Jim Talty
Utah State University