Cases of severe acute carbon tetrachloride poisoning are sporadically described in Spain. We report the cases of three patients that inhaled toxic vapour of carbon tetrachloride that they used as a solvent during their working activity. They developed hepatic disfunction and one of them acute renal failure. The interval between the labour exposure and the medical care was higher than 24 hours. All the patients received N-acetylcysteine treatment (300 mg/kg) and oxygen. The patient ith renal failure recurred hemodialysis. The basic aspects of diagnosis and treatment are commented.