Hydrogen peroxide controls odors in sewers by:

Hydrogen peroxide is effective in controlling odors in sewers primarily because it functions as a strong oxidizing agent. When introduced into a sewer system, hydrogen peroxide oxidizes sulfide compounds, notably hydrogen sulfide (H₂S), which is notorious for its foul odor. The oxidation process converts these smelly sulfide compounds into less odorous or odorless substances, such as sulfate or elemental sulfur.

By addressing the root cause of the odors — the presence of these sulfide compounds — hydrogen peroxide significantly reduces the unpleasant smells emanating from the sewage system. This approach is especially valuable in wastewater management, as it helps maintain a more sanitary and less offensive environment in treatment facilities and nearby areas.

Options that suggest decreasing dissolved oxygen or neutralizing pH do not directly relate to odor control through the targeted oxidation of sulfide compounds; therefore, they do not effectively align with the primary mechanism by which hydrogen peroxide combats odors. Providing a source of hydrogen ions is also not a main function of hydrogen peroxide regarding odor control, as the removal of sulfide compounds is the key process here.