Sewer gas Sewer gas Sewer gas is a complex mixture of toxic and nontoxic gases produced and collected in sewage systems by the decomposition of organic household or industrial wastes, typical components of sewage. Sewer gases may include hydrogen sulfide, ammonia, methane, esters, carbon monoxide, sulfur dioxide and nitrogen oxides. Improper disposal of petroleum products such as gasoline and mineral spirits contribute to sewer gas hazards. Sewer gases are of concern due to their odor, health effects, and potential for creating fire or explosions. Sewer gas is typically restricted from entering buildings through plumbing traps that create a water seal at potential
Gas gangrene as a degree of loud and distinctive crepitus caused by gas escaping the necrotic tissue. Gas gangrene is caused by exotoxin-producing "Clostridium" species (most often "C. perfringens", and "C. novyi", but less commonly "C. septicum" or "C. ramnosum"), which are mostly found in soil, but also found as normal gut flora, and other anaerobes (e.g., "Bacteroides" and anaerobic streptococci). The exotoxin is commonly found in "C. perfringens" type A strain and is known as alpha toxin. This alpha toxin is a lethal toxin and also known as phospholipase C (lecithinase). It increases vascular permeability and produces necrotizing activity. These environmental