Cadmium and its Compounds

Cadmium

Main Industries and Occupations At Risk

  • Waste treatment plants handling cadmium-containing waste;
  • Sampling of waste water from plants handling cadmium;
  • Cadmium electroplating;
  • Plastics industry, especially compounding of polyvinyl chloride (PVC); used as thermal stabiliser;
  • Nickel-cadmium battery manufacturing (tableting and assembly of Cd electrodes);
  • Pigment manufacture and use e.g., for plastics, textile, paper, rubber industries; in inks, enamels and glazes;
  • Alloy manufacture, e.g., low melting-point brazing alloys, Ag-Cd & Cu-Cd;
  • Fungicides manufacture and use;
  • Silver brazing using cadmium-containing fillers, welding on cadmium-containing alloys;
  • Manufacture of refrigerators, air-conditioners, television picture tubes, semiconductors, photo-cells & fl uorescent lamps, and as neutron absorber in nuclear reactors;
  • Jewellery manufacture;
  • Automobile and aircraft industries;
  • Smelting and refining of Zn, Pb or Cu ores and scrap processing;
  • Spray painting using cadmium-containing paints, removal of cadmium paints by blasting or scraping;
  • Manufacture of cadmium telluride solar panels.
  • Footnote: Locally, high exposures are sometimes seen in the Waste treatment industry.

Medical Examinations

Indications:

  • Any work where workers are exposed to cadmium.

Types of Tests and Frequency of Examinations:

  • Pre-placement medical examination: within three months of exposure
    • Clinical examination shall include a detailed medical and work history with emphasis on:
      • i.  past, present, and anticipated future exposure to cadmium;
      • ii. renal, olfactory, cardiovascular, respiratory, haematopoietic, reproductive, and/or musculo-skeletal system dysfunction;
      • iii. current usage of medication with potential nephrotoxic side-effects;
      • iv. a history of smoking.
    • Tests:
      • i. Blood cadmium (B-Cd) estimation (venous blood in heparinised container);
      • ii. Urine Beta2 – microglobulin (U-β2m) estimation.
      • Note:  Special instruction for collection of specimen for U-β2m estimation:
        • DO NOT USE EARLY MORNING URINE SPECIMEN.
        • Collect morning urine specimen 2 hours after drinking 15 ml. Mist Potassium Citrate.
        • Discard specimen if urine pH lower than 5.6.
        • Keep specimen refrigerated after collection and in ice during transportation.
        • Specimens should reach the laboratory within 2 hours after collection.
    • Unfit for exposure to cadmium:
      • i. History of renal dysfunction or persons with raised U-β2m test results;
      • ii. Pregnant women.
  • Periodic medical examinations: every 12 months
    • Clinical examination shall include a detailed medical and work history with emphasis on:
      • i.  renal, olfactory, cardiovascular, respiratory, haematopoietic, reproductive, and/or musculo-skeletal system dysfunction;
      • ii.  current usage of medication with potential nephrotoxic side-effects;
      • iii.  a history of smoking.
    •  Tests:
      • i.  B-Cd estimation (venous blood in heparinised container)
        BTLV for B-Cd   = 5 mcg/L    Action Level for B-Cd  = 4 mcg/L
      • ii. U-β2m estimation   Normal level ≤290 mcg/L Creatinine