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From: Robert Swotinsky MD
Password: orange
Date: 15 Nov 2006
Time: 12:43:37 -0800
Remote Name: 65.206.105.12
It is highly unlikely that someone, even someone with hepatitis, would test positive for cannabinoids by an immunoassay screen 59 days after last use. There are no scientific studies that address marijuana metabolite urine levels among individuals with liver disease. The available literature is instead based on individuals with healthy livers, and in many cases is based on GC/MS tests for THCA (as opposed to immunoassay screens for multiple THC metabolites). Since marijuana is metabolized in the liver, it's possible that liver disease would slow down metabolism and result in longer excretion. Based on my knowledge of the literature and experience as an MRO, I think it highly unlikely that the individual abstained for 59 days and nevertheless tested positive by immunoassay. If the two positive samples were retained, you might consider sending them for lab-based tests that include creatinine, and then comparing the creatinine-adjusted THC values. A ratio of 0.5 or greater between two creatinine-adjusted positive cannabinoid tests can help differentiate between new use and residual excretion.