Effects of oral fluid contamination on two oral fluid testing systems.

Oral fluid is a popular matrix for drug testing; however, little has been published concerning the effect that food or beverages may exert on oral fluid screening tests. This study describes the effects of 19 different foods, beverages and vinegars on two test systems, the Concateno Certus and Orasure Intercept. Samples giving positive screening results were subjected to confirmatory analysis using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry.