What are the primary sources of phosphorous in municipal wastewater?

The option identifying human waste and detergents as the primary sources of phosphorus in municipal wastewater is accurate because both of these components significantly contribute to phosphorus levels.

Human waste contains phosphorus primarily from bodily waste, as it's a key element found in organic matter, including food consumed by individuals. This organic matter is broken down in wastewater treatment processes, thereby releasing phosphorus into the wastewater stream.

Detergents are another major source of phosphorus. Many types of laundry and dishwashing detergents used in households and businesses have historically contained phosphates, which are compounds of phosphorus. Though regulations have shifted to limit or ban phosphorus in detergents in many regions, it has nevertheless historically contributed significantly to phosphorus levels in wastewater.

In contrast, while pesticides, industrial discharge, and agricultural runoff can contain phosphorus, they are not the primary sources in the context of municipal wastewater treatment. These sources are typically more relevant in discussions about environmental phosphorus loading into bodies of water rather than directly from municipal wastewater treatment systems.