The effects of commonly used adulterants on the detection of spiked LSD by an enzyme immunoassay

The effects of 15 chemicals and household agents on an enzyme immunoassay (EIA) for LSD were investigated. The presence of many of these was detected by pH and specific gravity measurements and by sample inspection. A number of agents caused false positives in the assay at 10% adulteration, but only two produced false positive results at 1%. Adulterated samples spiked with LSD produced no false negatives, demonstrating that none of the adulterants tested were able to conceal the presence of LSD by interfering with the EIA. The assay is shown to be a robust method for the screening of urine for LSD when used in conjunction with sample inspection and a sound confirmatory method.