A specific activity effect in the metabolism of Tc.
A study of transfer to milk of three isotopes of Tc indicated different results for 99mTcO4-, 95mTcO4-, and 99TcO4-. When the three isotopes were given orally to lactating goats in separate experiments, the milk transfer coefficients increased with decreasing specific activity. Gut absorption of Tc administered as pertechnetate (TcO4-) was decreased by reduction of TcO4- in the rumen. The rate of reduction of TcO4- in the rumen was greater for higher specific activity doses of Tc. These results suggest that the specific activity of a radioisotope may significantly influence the estimated dose to humans from contaminated milk and, probably, other food products.
Ennis
M E
ME
Department of Radiology and Radiation Biology, Colorado State University, Fort Collins 80523.
Johnson
J E
JE
Ward
G M
GM
Voigt
G M
GM
D000818:Animals; D005507:Food Contamination, Radioactive; D006041:Goats; D008892:Milk / Q000378:metabolism*; D011851:Radioactivity; D013667:Technetium / Q000378:metabolism*
D013667:Technetium