تسجيل الدخول

تسجيل

Sweat

المؤلف:  Sue Jickells , Adam Negrusz (Editors)

المصدر:  Clarkes Analytical Forensic Toxicology

الجزء والصفحة:  p142-144

2026-10-03

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Sweat

• According to the 2004 HHS proposals, lab oratories are permitted to test initially all specimens for MAM at 25 ng/patch.

• As for oral fluid, for a specimen to be positive for methamfetamine it must contain amfetamine at a concentration equal to or greater than the limit of detection.

Clearly, there will be a dramatic increase in the complexity of the analyses needed to test these alternative specimens for workplace drug testing, and in the proficiency testing and inspection programmes involved in certifying laboratories to do such testing. Although no mention has yet been made regarding the specimen volume to be collected, it is important to realise that the current urine testing programme requires the collection of at least 45 mL which is divided into two samples: A and B. Sample A is the specimen analysed by the testing laboratory. Sample B is considered to be the donor’s and can only be opened at the request of the donor. It is sealed and stored under suitable conditions and the A sample is analysed. If the A sample is found to be positive, the donor may request analysis of the B sample. The bottle is normally opened for re-test purposes by a second certified laboratory. Given the sensitivity of current technology available for testing urine specimens, there are no concerns regarding specimen availability during this process. However, that may not be the case for the alternative specimens, for which the minimum specimen sizes are recommended to be: hair, 100 mg; oral fluid, 2 mL (1.5 mL for the primary specimen and 0.5 mL for the split specimen); and sweat, one FDA-approved patch worn for 7–14 days. The implementation of these proposed guide lines will require laboratories to be proficient in the use of more sensitive immunoassays (particularly enzyme-linked immunosorbent assay (ELISA)) and tandem mass spectrometry (probably with an LC interface). Included in Table 5.7 is a comparison of hair, oral fluid and sweat as specimens for drug detection.