Pitfalls in hair analysis - GTFCh

Psychemedics drug and alcohol hair test result. DETECTION PERIOD OF THE TEST Detection Period (HEAD HAIR) - A standard hair test tests a 3.9cm length of hair. This equates to an approximate three (3) month detection period. Head hair grows at a rate of 1.3cm per month. Approximately seven (7) days of hair growth resides below the skin surface. ................
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