Which chemical compounds are commonly associated with wastewater odors?

Nitrogen and sulfur compounds are commonly associated with wastewater odors due to their involvement in biological processes occurring during decomposition.

In wastewater treatment plants and other environments where organic matter decomposes, various microorganisms break down proteins and other nitrogen-rich materials, leading to the release of ammonia and other nitrogen compounds. Ammonia has a distinct, unpleasant odor often associated with sewage.

Simultaneously, sulfur compounds such as hydrogen sulfide are produced during the anaerobic digestion of organic matter, particularly in the absence of oxygen. Hydrogen sulfide has a characteristic rotten egg smell and is notorious for its strong odor even in very low concentrations. The presence of these nitrogen and sulfur compounds in wastewater is a primary cause of the foul odors that can emanate from untreated sewage or poorly managed wastewater treatment facilities.

In contrast, the other combinations do not correlate as strongly with wastewater odors. Oxygen, while critical for aerobic treatment processes, does not contribute to the odor itself. Hydrogen and carbon are more associated with organic compounds but lack the strong, recognizable odors linked to nitrogen and sulfur compounds.