Quote:
Nitrites can be readily detected by a urinalysis dipstick test or through direct chemical analysis. Because nitrites do not interfere with immunoassays, samples containing concentrations of THC above the threshold will be routinely assayed for the THC-COOH metabolite by GC/MS. A urine sample that exhibits little or no recovery of a deuterated IS or target drug is highly suggestive of an adulterant such as nitrite (2).
Using elemental analysis, mass spectrometry (for pyridine), ion chromatography (for chloride), and inductively coupled plasma atomic emission spectroscopy, the active ingredient in Urine Luck was determined to be PCC. Urine samples adulterated with PCC tested by GC/MS will produce results that are similar to those for nitrite, i.e., low or no recovery of the IS or target drug. This adulterant differs from nitrite, however, because at high concentrations, the chemical also produces negative immunoassay screening results. Thus, drug testing laboratories unaware of the presence of PCC will not perform GC/MS analysis, and the use of PCC may escape detection. Its presence can be suspected by the presence of an abnormally low pH or the appearance of an orange tint to the urine.
So basically if you can get through without a GC/MS run you may be ok. If not, this stuff will destroy the internal standard which sets off a red flag that the sample may contain an adulterant. An inexperienced GC/MS operator could misinterpret results like this but I have a feeling someone more experienced would have to sign off on it and thus, would recognize.
References:
(1)Alan H.B. Wu,a, Ben Bristol, Karen Sexton, Gina Cassella-McLane, Verena Holtman and Dennis W. Hill. "Adulteration of Urine by "Urine Luck" Clinical Chemistry 45: 1051-1057, 1999;
(2)ElSohly MA, Feng S, Kopycki WJ, Murphy TP, Jones AB, Davis A, Carr D. A procedure to overcome interferences caused by the adulterant "Klear" in the GC-MS analysis of 11-nor-9-THC-9COOH. J Anal Toxicol 1997;21:240-242
Your references are outdated - made long before the current methodologies mandated by DHHS/SAMHSA/DOT:
Quote:
Subpart F - Drug Testing Laboratories
§ 40.95 What are the adulterant cutoff concentrations for initial and confirmation tests?
(a) As a laboratory, you must use the cutoff concentrations for the initial and confirmation adulterant testing as required by the HHS Mandatory Guidelines and you must use two separate aliquots ?? one for the initial test and another for the confirmation test.
(b) As a laboratory, you must report results at or above the cutoffs (or for pH, at or above or below the values, as appropriate) as adulterated and provide the numerical value that supports the adulterated result.
[65 FR 79526, December 19, 2000, as amended at 73 FR 35970, June 25, 2008]
Which brings us to....