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From: Robert Swotinsky MD
Password: orange
Date: 16 Aug 2009
Time: 16:23:56 -0700
Remote Name: 98.229.131.90
You asked how much drug/metabolite will deteriorate in a non-DOT split specimen that has been stored for 1-2 months and is now being tested. I can't exactly answer your question. But, I can offer a few comments that you may find sufficient.
(1) Under DOT, the donor gets 72 hours in which to ask for his/her split. You're in a non-DOT setting in which apparently a longer period of time has been allowed for initiation of the split test. If that's what the policy calls for, or if that's what the arbitrator has ordered, so be it.
(2) The split test is different than the primary test. The split test identifies the presence of drugs/metabolites at or above the limit of detection (LOD). A laboratory's LOD is the lowest concentration at which an analyte can be reliably shown to be present. LODs are much lower than cutoff values. The LOD is used instead of the cutoff value for several reasons, including the possibility that some drug/metabolite will deteriorate over time, even in split specimens while stored in the freezer. This phenomenon is thought to be more significant for marijuana and 6-AM than most other drugs, such as amphetamine. Another reason for testing to the LOD is the possibility that a slow-acting adulterant will degrade the drug/metabolite, allowing a positive result in the primary test but a failure to reconfirm with the split. This latter scenario is also unlikely, though, because the timing and the rate of adulterant activity would have to be just right to allow a positive initial result but sub-LOD split result.