Tritiated bile acids: problems and recommendations.

Kinetic studies of cholic and chenodeoxycholic acids were carried out in three patients by simultaneous intravenous administration of appropriate pairs of (3)H- and (14)C-labeled compounds. The results obtained indicated two sources of error: chemical impurity and loss of tritium by biological exchange. Precautions are listed for use of tritiated bile acids in studies of pool sizes and turnover rates.