[Nervous system damage caused by H2S poisoning without unconsciousness]

Acute H2S (hydrogen sulfide) poisoning can cause permanent damage to the nervous system. We describe two patients with such damage. Both reported nausea, feeling unwell and irritation of the eyes during work, and have developed persistent memory problems and neurasthenic symptoms. Neither of them had been unconscious. The first patient was exposed during one and a half hours welding of a sewage pump. The second patient worked for three weeks in a laboratory where hydrogen sulfide leaked from faulty equipment. The cases demonstrate the need for thorough work and symptom anamnesis together with neuropsychological testing in order to achieve a correct diagnosis of encephalopathy caused by hydrogen sulfide exposure.