What is H2S

Hydrogen sulfide (H2S), a chemical compound, is a colorless gas that has an overpowering odor likened to rotten eggs. Hydrogen sulfide is naturally produced when organic materials undergo a microbial breakdown and oxygen is absent. Hydrogen sulfide is heavier than air and therefore found in low lying areas. H2S is poisonous and considered highly toxic to human health. This is because H2S akin to carbon monoxide (CO) prevents cellular respiration. Hydrogen sulfide is also flammable, highly reactive, and is a corrosive agent.