A Fatal Exposure to Hydrogen Sulfide

Document Type

Conference Proceeding

Publication Date


Publication Title

J Med Toxicol


Background: Hydrogen Sulfide (H2S) is considered a “knock down” agent. Inhalation of H2S causes cellular asphyxia, collapse, and cardiac arrest. We report a case of a 56-year-old male who suffered a fatal exposure to hydrogen sulfide gas while cleaning the interior of a hazardous waste disposal truck.

Methods: Single-patient chart review. Case: A 56-year-old male was cleaning the interior of a tanker truck at a hazardous waste disposal site. He removed his personal protective equipment to better visualize the interior of the tank. He then stood up and collapsed. He fell from the top of the truck, landing on his head. Coworkers found him in cardiac arrest and performed CPR. EMS arrived and transported the patient to a local ED. On arrival to the ED, ACLS protocol was initiated. His evaluation was complicated by a lack of information regarding hazardous materials present at his work site, and the presence of white powder covering his body. Because of a concern for cyanide exposure, the patient was given hydroxocobalamin with rapid return of circulation. Following resuscitation, diagnostic testing showed severe metabolic and respiratory acidosis. Radiographic studies showed multiple traumatic injuries including subarachnoid hemorrhage and cerebral edema. Testing at the exposure site by HAZMAT confirmed the presence of hydrogen sulfide gas. The white powder was identified as calcium carbonate. In the ICU, his acid-base status improved; however, his cardiovascular status deteriorated. Based on his poor neurologic prognosis, further resuscitative measures were not attempted. He died on hospital day two.

Discussion: Clinicians should maintain awareness of hydrogen sulfide as a “knock down” gas and potential cause of sudden cardiac arrest. Inhalation of large quantities can be fatal and lead to cellular asphyxia and cardiopulmonary arrest. In this case, there was rapid return of circulation following administration of hydroxocobalamin, which is consistent with prior animal studies and case reports suggesting efficacy.

Conclusion: Those working near sources of hydrogen sulfide should wear personal protective equipment. Assessment of potentially hazardous exposures and appropriate decontamination procedures can assist in the rapid treatment of life-threatening exposures. Hydroxocobalamin should be considered for severe toxicity secondary to hydrogen sulfide exposure.





First Page


This document is currently not available here.