Ethylbenzene — biological monitoring
When to suspect: Styrene production (precursor), refinery/petrochemical, paint/coating solvent; present in petrol and mixed-xylene streams.
Urinary mandelic + phenylglyoxylic acid (g/g creatinine)
| Level | Interpretation |
|---|---|
| Negligible | Non-exposed (non-specific marker) |
| 0.15 | ACGIH BEI — last 4 h of last shift of workweek |
Shares MA+PGA with styrene — record other aromatic-solvent exposures. ACGIH A3 (animal carcinogen).
Biological exposure index
ACGIH BEI = 0.15 g/g creatinine MA+PGA, end of shift at end of workweek.
Basis: ACGIH BEI (LabCorp/NMS/Haz-Map; ATSDR).
Sample collection & preparation
- Spot urine in the last 4 h of the last shift of the workweek; plain container; co-measure creatinine.
- Note styrene/aromatic co-exposure.
Statutory basis. Factories Act 1948 sets only AIR limits (Second Schedule TWA/STEL, s.41F) and mandates the hazardous-process exam (s.41C, ≤12-monthly); it gives NO blood/urine values. The ranges below are ACGIH BEI / OSHA / clinical benchmarks (India has not adopted biological limits into law).
Reference information for occupational-health professionals — not medical advice, and not a substitute for examination by a qualified physician.
All 27 agents — toxicology & biological monitoring
MedFactory — Occupational Health Centre software for Indian factories