PAH (coke-oven / coal-tar) — biological monitoring

When to suspect: Coke ovens & coal-tar, aluminium (Söderberg) potrooms, roofing/road paving (bitumen), creosote/wood preservation, carbon-black, foundries, chimney sweeping, diesel exhaust.

Urinary 1-hydroxypyrene (1-OHP) (µg/L)

Level	Interpretation
< 0.5	General-population background
~1	Benchmark for occupational PAH exposure (not a formal BEI)

ACGIH lists 1-OHP as "Nq" (non-quantitative) — no numerical BEI. Smoking & charbroiled/smoked food raise levels.

Biological exposure index

No numerical ACGIH BEI (Nq). Committee benchmark: 1-OHP above ~1 µg/L (0.5 µmol/mol creatinine) = occupational PAH exposure. EOS at end of workweek.

Basis: ACGIH BEI "Nq"; Jongeneelen benchmark; NHANES background.

Sample collection & preparation

Spot urine, post-shift (often end of workweek); plain container; co-measure creatinine.
Record smoking + charbroiled/smoked food.
Protect from light; refrigerate/freeze.

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