5ml
Lithium Heparin Whole Blood
No gel separator tubes
Whole blood EDTA
No gel separator tubes
17 days
Refrigerated
Normal Range (<0.4ug/L)
NB: the quoted reference range is for the general population
Cobalt: 1 ug/L = 1 ppb (parts per billion)
Serum concentrations > 1 ug/L may indicate environmental or
occupational exposure. Levels greater than 5 ug/L may be considered potentially toxic.
UK MHRA recommendations for metal-on-metal hip replacements:
RANGES APPLY TO WHOLE BLOOD SAMPLES
If either cobalt or chromium ion levels are elevated above 7 ppb (i.e. 134 nmol/L Cr or 119 nmol/L Co ) then a 2nd
test should be performed three months after the first in order to identify patients who require closer surveillance,
which may include cross-sectional imaging.
Expected chromium and cobalt concentrations with well functioning hips:
Metal on plastic: chromium 0.8 ug/L; cobalt 0.6 ug/L.
Unilateral metal/metal: chromium 2.3 ug/L; cobalt 1.8 ug/L.
Bilateral metal on metal: chromium 2.3 ug/L; cobalt 2.6 ug/L
SAMPLE REQUIREMENTS FOR COAGULATION TESTS
PROCEDURE
Sample Requirements and Collection
Transportation and Storage