Cadmium

2020-06-19

Cadmium is a malleable blueish, silvery-white heavy metal. Commercially, it is produced as a by-product of treating other metals, including zinc, lead and copper ores. Today, cadmium is produced where zinc is refined, rather than where it is mined. It occurs naturally in the mineral Greenockite. Most cadmium compounds have been classified as a Category 1 carcinogen—carcinogenic in humans. [1,2,3]

Uses [3,4,5]

Cadmium is used across various industries, although it is being phased out, due to its toxicity. Its primary use is in rechargeable nickel-cadmium batteries. It is also found in cordless power tools, cameras, computers, emergency power supplies, mobile phones and lights. Cadmium is used in nuclear reactors to control atomic fission, and to electroplate steel to protect it from corrosion.

Routes of Exposure [4,6]

The primary route of exposure for cadmium is via inhalation.

Occupational exposure is a primary route of exposure.

Cigarette smoke contains cadmium; smokers may inhale twice the amount of cadmium as a non-smoker.

Vegetables grown in contaminated soils can have small traces of the heavy metal.

Livers and kidneys of shellfish and animals may contain higher amounts of cadmium than other foods.

Health Effects

Cadmium poisoning affects a range of systems including the respiratory and nervous systems.

Acute Effects [6]

Severity of symptoms depend on the level and type of exposure.

Initial inhalational exposure to the chemical can result in respiratory symptoms, including inflammation of the throat and a cough.

It can then be followed by ‘metal fume fever’: a flu-like illness with accompanying symptoms.

These symptoms include: conjunctivitis, sweating, muscle aches, fever and chills, a headache, a metallic taste in the mouth and an impaired sense of small.

Symptoms from eight hours to seven days post exposure include: nausea, diarrhoea, nocturia, abdominal pain, persistent cough, weakness and malaise and severe dyspnoea and wheezing.

Workers who have been exposure to the extremely irritating fume of heated carbon could experience pneumonitis or pulmonary oedema—with the onset of symptoms delayed for several hours or days.

  

Chronic Effects [6]

Cadmium is toxic to multiple body systems. Long-term exposure to the chemical can result in irreversible cadmium-induced tubular proteinuria. Chronic exposure to cadmium is associated with osteoporosis, increased fractures and osteomalacia. Long-term inhalation of the heavy metal can result in respiratory insufficiency, namely a chronic obstructive airway disease. Cadmium’s Category 1 status as a carcinogen is related specifically to the development of lung cancer.

Safety

~h2First Aid Measures [7]

  • Ingestion: DO NOT INDUCE VOMITING. Immediately contact a medical professional.
  • Skin contact: Immediately wash affected skin with water for at least 15 minutes, and remove contaminated clothing. Do not re-wear until it has been thoroughly de-contaminated. Continue rinsing contaminated skin. Immediately contact a healthcare professional.
  • Eye contact: Check for and remove contact lenses if easy to do so. Rinse eyes carefully with water or normal saline solution for at least 15 minutes. Take the victim to a medical centre.
  • Inhaled: Take victim to the nearest fresh air source and monitor their breathing. If they are not breathing, and you are qualified, you can administer CPR—with a pocket mask or one-way valve. Immediately contact a medical professional. 
  • General: Never administer anything by mouth to an unconscious, exposed person.

  • Exposure Controls/Personal Protection [7]

  • Engineering controls: Emergency eyewash fountains and safety showers should be accessible in the immediate area of the potential exposure. Ensure there is adequate ventilation. Only use cadmium under a chemical fume hood.

  • Personal protection: Safety glasses, protective and dustproof clothing, gloves, an apron and an appropriate mask. Follow the PPE guidelines set in your jurisdiction. 

Regulation [8]

~h2United States:

The Occupational Safety and Health Administration (OSHA) has set an 8-hour time weighted average (TWA) concentration limit for cadmium of 0.01mg/m3.

Australia [6]

Safe Work Australia has set an 8-hour time TWA for cadmium of 0.01mg/m3.

References

https://www.osha.gov/SLTC/cadmium/

https://www.betterhealth.vic.gov.au/health/HealthyLiving/cadmium

https://www.livescience.com/37044-cadmium.html

https://www.betterhealth.vic.gov.au/health/HealthyLiving/cadmium

https://www.rsc.org/periodic-table/element/48/cadmium

https://www.safeworkaustralia.gov.au/system/files/documents/2002/health_monitoring_guidance_-_cadmium.pdf

https://www.fishersci.com/store/msds?partNumber=C3500&productDescription=CADMIUM+METAL+GRAN+PURIF+500G&vendorId=VN00033897&countryCode=US&language=en

https://www.ncbi.nlm.nih.gov/books/NBK158839/table/T41/