Sodium Hydrosulfide

CAS RN:16721-80-5

Health Effects

    • A) USES: Used as drain openers, household cleaners (oven, bathroom), hair relaxers, dishwasher soap, and in automobile air bags. In industry used as cleaners, in cement, and as chemical precursors.
    • B) TOXICOLOGY: Alkaline corrosives cause liquefaction necrosis. They saponify the fats in the cell membrane, destroying the cell and allowing deep penetration into mucosal tissue. In gastrointestinal tissue an initial inflammatory phase may be followed by tissue necrosis (sometimes resulting in perforation), then granulation and finally stricture formation.
    • C) EPIDEMIOLOGY: Exposure is common. Serious effects are rare in the developed world (generally only seen in adults with deliberate ingestion), largely because mostly low concentration corrosives are present in products available in the home. Serious effects are more common in developing countries.
      • 1) MILD TO MODERATE ORAL TOXICITY: Patients with mild ingestions may only develop irritation or grade I (superficial hyperemia and edema) burns of the oropharynx, esophagus or stomach; acute or chronic complications are unlikely. Patients with moderate toxicity may develop grade II burns (superficial blisters, erosions and ulcerations) are at risk for subsequent stricture formation, particularly esophageal. Some patients (particularly young children) may develop upper airway edema.
        • a) Alkaline corrosive ingestion may produce burns to the oropharynx, upper airway, esophagus and occasionally stomach. Spontaneous vomiting may occur. The absence of visible oral burns does NOT reliably exclude the presence of esophageal burns. The presence of stridor, vomiting, drooling, and abdominal pain are associated with serious esophageal injury in most cases.
        • b) PREDICTIVE: The grade of mucosal injury at endoscopy is the strongest predictive factor for the occurrence of systemic and GI complications and mortality.
      • 2) SEVERE ORAL TOXICITY: May develop deep burns and necrosis of the gastrointestinal mucosa. Complications often include perforation (esophageal, gastric, rarely duodenal), fistula formation (tracheoesophageal, aortoesophageal), and gastrointestinal bleeding. Hypotension, tachycardia, tachypnea and, rarely, fever may develop. Stricture formation (esophageal, less often oral or gastric) is likely to develop long term. Esophageal carcinoma is another long term complication. Upper airway edema is common and often life threatening. Severe toxicity is generally limited to deliberate ingestions in adults in the US, because alkaline products available in the home are generally of low concentration.
      • 3) INHALATION EXPOSURE: Mild exposure may cause cough and bronchospasm. Severe inhalation may cause upper airway edema and burns, stridor, and rarely acute lung injury.
      • 4) OCULAR EXPOSURE: Ocular exposure can produce severe conjunctival irritation and chemosis, corneal epithelial defects, limbal ischemia, permanent visual loss and in severe cases perforation.
      • 5) DERMAL EXPOSURE: Mild exposure causes irritation and partial thickness burns. Metabolic acidosis may develop in patients with severe burns or shock. Prolonged exposure or high concentration products can cause full thickness burns.
    • A) USES: Hydrogen sulfide is a highly toxic, colorless gas. It is denser than air with a rotten egg odor. Hydrogen sulfide is produced naturally by biological degradation of sulfur-containing products (eg, fish, sewage, and manure) and produced as a byproduct in many industrial processes (ie, paper mills, heavy-water production, petroleum refineries, tanneries, mines, carbon disulfide production, and hot asphalt fumes). It can often be found naturally in sulfur hot springs, volcanoes, and underground deposits of natural gas.
    • B) TOXICOLOGY: It interrupts oxidative phosphorylation by inhibition of cytochrome oxidase a3. By inhibiting oxidative phosphorylation, hydrogen sulfide effectively causes cellular asphyxia.
    • C) EPIDEMIOLOGY: Hydrogen sulfide exposure is uncommon; however, with severe exposure manifestations are life-threatening.
      • 1) EXPOSURE: Hydrogen sulfide exposure occurs primarily by inhalation, but can also cause dermal and ocular injury. Suspect hydrogen sulfide toxicity in anyone found unconscious, in a confined space with an odor of rotten eggs present. Darkening of jewelry or silver coins in the vicinity of the victim should also heighten suspicion for hydrogen sulfide exposure.
      • 2) MILD TO MODERATE TOXICITY: In mild to moderate exposures, hydrogen sulfide is primarily an irritant causing upper-airway irritation, conjunctivitis, corneal injury, dermatitis, pharyngitis, pneumonitis, and pulmonary edema (which can be life-threatening). It can also manifest as headache, nausea, vomiting, chest pain, shortness of breath, weakness, dizziness, disequilibrium, keratoconjunctivitis, corneal ulceration and rarely irreversible corneal scarring.
      • 3) SEVERE TOXICITY: Severe exposure manifests as central nervous system depression, seizures, coma, hemoptysis, myocardial ischemia, dysrhythmias, acute lung injury, and death. Central nervous system depression is usually rapid and profound. While recovery may be complete in patients rapidly removed from exposure, permanent sequelae (eg, dementia, memory failure, delirium, ataxia, tremor, muscle rigidity) may result from prolonged hypoxia.
  • A) Spontaneous abortions have occurred after exposure to life-threatening concentrations.
    • A) IARC Carcinogenicity Ratings for CAS7783-06-4 (International Agency for Research on Cancer (IARC), 2016; International Agency for Research on Cancer, 2015; IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2010; IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2010a; IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2008; IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2007; IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2006; IARC, 2004):
      • 1) Not Listed
    • A) In Rotorua, New Zealand (an active geothermal zone where hydrogen sulfide is released to the atmosphere), cancer deaths were not related to the extent of hydrogen sulfide exposure and there was no overall excess mortality found.
  • A) Hydrogen sulfide exposure was associated with an increased risk of chromosome aberrations in chemical workers. Other factors may be involved in these multiply-exposed cohort populations.
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