Method: GC-MS (Gas Chromatography/Mass Spectrometry) measuring organic acid metabolites in urine (CLIA 17D0919496); not cleared or approved by the FDA. Results in mmol/mol creatinine. Not a stand-alone diagnosis; should be interpreted in clinical context.
Mandelic acid has two origins: normal phenylalanine breakdown, and as a major byproduct of styrene, an industrial chemical in plastics, resins, and packaging.



