Excreta reuse

Reuse of excreta (or re-use or use of excreta) refers to the safe, beneficial use of animal or human excreta, i.e. feces (or faeces in British English) and urine. Such beneficial use involves mainly the nutrient, organic matter and energy contained in excreta, rather than the water content (as is the case for wastewater reuse). Reuse of excreta can involve using it as soil conditioner or fertilizer in agriculture, gardening, aquaculture or horticultural activities. Excreta can also be used as a fuel source or as a building material.

Excreta contains resources that can be recovered: plant-available nutrients nitrogen, phosphorus, potassium as well as micronutrients such as sulphur and organic matter. These resources which are contained in excreta or in domestic wastewater (sewage) have traditionally been used in agriculture in many countries. They are still being used in agriculture to this day, but the practice is often carried out in an unregulated and unsafe manner in developing countries. The WHO Guidelines from 2006 have set up a framework how this reuse can be done safely by following a "multiple barrier approach".

There are a number of "excreta-derived fertilizers" which vary in their properties and fertilizing characteristics: urine, dried feces, composted feces, fecal sludge (septage), sewage, sewage sludge and animal manure.

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