Styrene Urine Testing

Solvents & VOCs · Solvents & VOCs overview

Styrene exposure is verified by measuring the sum of urinary mandelic acid and phenylglyoxylic acid. The combined biomarker captures the major metabolic pathway and is the standard end-of-shift test for GRP, FRP and styrene-based composite operations.

Biomarker and reference value

Styrene is oxidised to styrene-7,8-oxide, hydrolysed to styrene glycol and then to mandelic acid and phenylglyoxylic acid. The sum of urinary mandelic + phenylglyoxylic acid is the recommended biomarker. ACGIH BEI is 400 mg/g creatinine end-of-shift; HSE has no published BMGV.

Glass-reinforced plastic operations

Open-mould GRP lay-up, spray-up and pultrusion processes produce high airborne styrene concentrations and significant dermal uptake from resin contact. Biomonitoring is the most reliable verification method because RPE fit and glove integrity dominate the dose more than air concentration alone.

Practical sampling

End-of-shift urine; samples are stable for 24 h at 4 °C. Smokers and recent dietary mandelate intake (almonds, bitter cherries) can affect background; document confounders.