Cadmium — biological monitoring
When to suspect: Ni-Cd battery mfg/recycling, electroplating, pigments, PVC stabilisers, alloy & solder, smelting.
Cadmium — blood (CdB) & urine (CdU); β2-microglobulin (renal) (µg/L · µg/g creat)
| Level | Interpretation |
|---|---|
| CdB < 1 / CdU < 1–2 | Non-exposed (higher in smokers) |
| CdB 5 / CdU 5 | ACGIH BEI (sampling time not critical) |
| OSHA 5/10/15 | CdB & CdU action tiers; > 10–15 = mandatory medical removal |
| β2M > 300 | Proximal tubular dysfunction (µg/g creatinine); 1500 = removal |
Pair CdU with urine β2-microglobulin (renal-effect marker; not a BEI).
Biological exposure index
ACGIH BEI: blood Cd 5 µg/L, urine Cd 5 µg/g creatinine (not time-critical). OSHA 29 CFR 1910.1027 removal tiers.
Basis: ACGIH BEI; OSHA 1910.1027 App F.
Sample collection & preparation
- Blood: royal-blue-top K2EDTA. Urine: acid-washed / trace-element-free cup, no metal cap.
- Sampling time not critical (long half-life); collect at start of shift to limit contamination; blood + urine same day.
- Stop supplements; avoid within 72 h of iodinated contrast; remove work clothing / wash hands.
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