Hydrogen sulphide inhalational toxicity at a petroleum refinery in Sri Lanka: a case series of seven survivors following an industrial accident and a brief review of medical literature

Abstract

This case series details clinical observations in 7 survivors of accidental hydrogen sulphide inhalation toxicity at a petroleum refinery in Sri Lanka. One survivor developed status epilepticus and severe neurotoxicity whilst another survivor developed delayed respiratory failure; both patients required intensive care management. One victim manifested mild bronchospasms in the immediate post-exposure period and another developed mild perioral numbness 2 days following the exposure. A brief literature review explores the manifestations, pathophysiology and available modalities of treatment of hydrogen sulphide inhalation toxicity.BackgroundHydrogen sulphide (H2S) is a highly toxic gas. Accidental deaths following H2S exposure is a known hazard amongst petroleum workers exposed to by-products of refineries. Toxicity results mainly due to cellular respiratory poisoning which impairs oxidative phosphorylation. The heart, brain and the lungs are the organs most commonly affected in H2S inhalational toxicity leading to varied clinical presentations.

Acute hydrogen sulfide–induced neuropathology and neurological sequelae: challenges for translational neuroprotective research

“…It is common for victims of acute H 2 S intoxication to develop chronic neurological sequelae. These neurologic effects include recurrent seizures, persistent headache, nausea, vomiting, fatigue, hearing impairment, movement disorders (e.g., spasticity, ataxia), altered psychological states, memory impairment, vision impairment (blindness and color discrimination errors), anosmia, amnesia, psychosis, prolonged coma, persistent vegetative state, anxiety, depression, and sleeping disorders …”

“…These neurologic effects include recurrent seizures, persistent headache, nausea, vomiting, fatigue, hearing impairment, movement disorders (e.g., spasticity, ataxia), altered psychological states, memory impairment, vision impairment (blindness and color discrimination errors), anosmia, amnesia, psychosis, prolonged coma, persistent vegetative state, anxiety, depression, and sleeping disorders. 6,7,30,[32][33][34][35][36][37][38][39][40][41][42][43][44][45] Typically, neurological sequelae have been reported in human victims of H 2 S poisoning who experience coma for periods ranging from 5 to 30 minutes. 34,35 In some reported cases, victims treated for H 2 S exposure recover from the acute effects of H 2 S poisoning and are discharged, only for postexposure neurologic complications to manifest days after apparent recovery.…”

Aggravation of Seizure‐like Events by Hydrogen Sulfide: Involvement of Multiple Targets that Control Neuronal Excitability

“…On the other hand, H 2 S can maintain the excitatory/inhibitory balance in neurotransmission and regulate the activity of a number of targets involved in seizures such as ion channel and NMDA receptor (NMDAR) . Moreover, one survivor of accidental H 2 S inhalation toxicity developed status epilepticus and severe neurotoxicity in Sri Lanka . All of the above evidence suggests that H 2 S may serve as a risk factor for seizures after stroke.…”

Short-term effects of subchronic low-level hydrogen sulfide exposure on oil field workers

“…It was reported that exposure to higher H 2 S concentration caused severe neurotoxicity, status epilepticus, bronchospasms, and delayed respiratory failure [2]. Following inhalation, H 2 S dissociates into free sulfide and hydrogen ions in the blood circulation.…”