Nickel — biological monitoring
When to suspect: Electroplating, stainless-steel & Ni-alloy production/welding, NiCd/NiMH battery mfg, catalysts, refining, pigments. (Nickel carbonyl is separately, acutely toxic.)
Urinary nickel (µg/g creatinine)
| Level | Interpretation |
|---|---|
| < 3.8 / 4.3 | Reference (male / female), non-exposed |
| ~30 | Reference-lab occupational action level (soluble) — NOT a BEI |
| > 50 | Excessive exposure |
No ACGIH BEI for nickel — the thresholds are reference-laboratory guidelines (Labcorp/Mayo), not regulatory limits.
Biological exposure index
No ACGIH BEI (TLV-TWA only). Reference-lab action ~30 µg/g creatinine (soluble compounds).
Basis: Reference-lab guidelines (Labcorp/Mayo); ACGIH has no Ni BEI.
Sample collection & preparation
- Spot or 24-h urine; acid-washed metal-free container, NO preservative (mercuric-oxide preservative interferes).
- Avoid metal contact — external contamination is a common false elevation. ICP-MS.
- Co-measure creatinine.
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