Determination of serum levels of dietary thiocyanate.

A spectrophotometric method was used to determine thiocyanate (SCN-) levels in human serum, in an attempt to relate serum levels of this ion to the dietary intake of vegetables of the genus Brassica. Thiocyanate ion was measured before and after a one-week period during which the subjects ate a diet rich in these vegetables. We also determined the serum increase in SCN- 2 h after the administration of 0.5 g KSCN.