Chromium Trioxide


Chemical information

Anhídrido Crómico; Chromic Acid; Chromic Anhydride; Chromu(VI) tlenek; Cromo, trióxido de.
Chemical formula: CrO3 = 99.99.
CAS — 1333-82-0.


Chromium trioxide and other chromium compounds are used in industry. Solutions of chromium trioxide are corrosive, acting by oxidation. Repeated contact with chromium and its salts may cause eczematous dermatitis, particularly in hypersensitive persons and can also cause deep perforating ulcers known as ‘chrome holes’. If inhaled, chromic dusts cause rhinitis and painless ulcers which may perforate the nasal septum; inhalation may cause severe lung damage and inflammation of the eyes. There may also be involvement of the CNS and there is an increased risk of lung cancer. Hexavalent chromium compounds are more dangerous than di- or trivalent compounds. Acute symptoms of poisoning from the ingestion of chromium salts include intense thirst, dizziness, abdominal pain with vomiting and diarrhoea, hepatic injury, anuria or oliguria, and peripheral vascular collapse. Kidney damage may lead to fatal uraemia. Treatment is symptomatic and supportive. Protective measures should be taken when handling or working with chromium and its salts. Chromium trioxide was formerly used as a caustic and astringent.

Adverse effects.

General references1-4 to chromium toxicity including reports of poisoning with ammonium dichromate,5chromium tripicolinate,6 chromium trioxide,7 potassium dichromate,8-10 and sodium dichromate.11
1. WHO. Chromium. Environmental Health Criteri
61. Geneva: WHO, 1988. Available at: ehc/ehc/ehc61.htm (accessed 30/07/08
2. Health and Safety Executive. The toxicity of chromium and inorganic chromium compounds. Toxicity Revie
21. London: HMSO, 1989
3. Barceloux DG. Chromium. J Toxicol Clin Toxicol 1999; 37: 173–94
4. Dayan AD, Paine AJ. Mechanisms of chromium toxicity, carcinogenicity and allergenicity: review of the literature from 1985 to 2000. Hum Exp Toxicol 2001; 20: 439–51
5. Meert KL, et al. Acute ammonium dichromate poisoning. Ann Emerg Med 1994; 24: 748–50
6. Cerulli J, et al. Chromium picolinate toxicity. Ann Pharmacother 1998; 32: 428–31
7. Matey P, et al. Chromic acid burns: early aggressive excision is the best method to prevent systemic toxicity. J Burn Care Rehabil 2000; 21: 241–5
8. Michie CA, et al. Poisoning with a traditional remedy containing potassium dichromate. Hum Exp Toxicol 1991; 10: 129–31
9. Stift A, et al. Liver transplantation for potassium dichromate poisoning. N Engl J Med 1998; 338: 766–7
10. Kolacinski Z, et al. Acute potassium dichromate poisoning: a toxicokinetic case study. J Toxicol Clin Toxicol 1999; 37: 785–91
11. Ellis EN, et al. Effects of hemodialysis and dimercaprol in acute dichromate poisoning. J Toxicol Clin Toxicol 1982; 19: 249–58.


Chromium trioxide is a powerful oxidising agent and is liable to explode in contact with small quantities of alcohol, ether, glycerol, and other organic substances.
Published March 19, 2019.