IT has been assumed that there is only one form of fluoride in serum, the inorganic F ion. It would therefore seem that either the value for serum fluoride which I found (1 µM) (refs. 1 and 2 ...

A serum iron test can reveal unusually low or high blood iron levels. Your doctor will most likely order this test after another lab test shows an abnormal result. Having too much iron — or not ...