Arsenic (inorganic) — biological monitoring
When to suspect: Smelting, glass, wood preservatives, pesticides, semiconductor (GaAs), alloy & e-waste.
Urinary inorganic As + methylated metabolites (speciated) (µg As/L)
| Level | Interpretation |
|---|---|
| < 10–15 | Non-exposed background (sum inorganic + MMA + DMA), excluding seafood |
| 35 | ACGIH BEI — sampled END OF WORKWEEK |
Speciate (inorganic + MMA + DMA, EXCLUDING arsenobetaine) — total urine arsenic is confounded by seafood.
Biological exposure index
ACGIH BEI = 35 µg As/L (sum of inorganic + methylated), end of workweek.
Basis: ACGIH BEI; ATSDR clinical guidance.
Sample collection & preparation
- Acid-washed / trace-element-free plastic; no metal cap; do not transfer with metal utensils. 24-h or creatinine-corrected spot.
- Collect END OF SHIFT at END OF WORKWEEK.
- MUST avoid all seafood/shellfish 48–72 h before AND during collection (dietary organic arsenic massively elevates results).
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