What type of gas is commonly produced during the decomposition of organic material in sewers?

During the decomposition of organic material in sewers, hydrogen sulfide is a common gas produced. This gas originates from the breakdown of sulfur-containing amino acids and proteins by bacteria in anaerobic conditions, which are often present in sewer environments where oxygen is limited. Hydrogen sulfide is particularly notable because it has a characteristic rotten egg odor and can be hazardous at higher concentrations, posing risks to health and safety.

While other gases may also be produced during decomposition, such as carbon dioxide and methane, hydrogen sulfide is specifically associated with the anaerobic decomposition of organic matter in sewers. Carbon dioxide is a more generalized byproduct of decomposition, while methane, although produced under anaerobic conditions, is not as closely identified with the immediate sewer environment compared to hydrogen sulfide. Chlorine, on the other hand, is typically associated with disinfection processes rather than organic decomposition.