Sensitive biomonitoring of monoterpene exposure by gas chromatographic–mass spectrometric measurement of hydroxy terpenes in urine

A gas chromatographic method with mass selective detection was developed which enables the simultaneous determination of the urinary hydroxy terpenes cis-verbenol, α-terpineol, myrtenol, carveol, perillyl alcohol and trans-sobrerol. The sample preparation consisted of enzymatic hydrolysis, solid phase extraction (SPE) with RP-C18 SPE material and clean up with silica gel cartridges. Large volume injection was used and the mass selective detection was done in the single ion modus. Low detection limits in the range of 1.0–4.5 μg/l for the terpene metabolites in urine and mean recoveries of 100% were achieved.