Lavender-top (EDTA) tube or green-top (heparin) tube;
7 mL WHOLE BLOOD submit original FULL, UNOPENED tube.
Refrigerate immediately after collection. Do not remove cap.
Sampling time is end of shift for industrial exposure monitoring. Analytes with timing end of shift (meaning the last two hours of exposure) are eliminated rapidly with a half-life less than five hours. Such compounds do not accumulate in the body and, therefore, their timing is critical only in relation to the exposure period.