Reuse of excreta
Reuse of excreta (alternative spelling: re-use) refers to the safe, beneficial use of animal or human excreta, i.e. feces (or faeces in British English) and urine. Such beneficial use can be as a soil conditioner or fertilizer in agriculture, gardening, aquaculture or ornamental activities. Other possible uses include use as building material, fuel source or protein production. An alternative term is also ""use of excreta"" rather than ""reuse"" as strictly speaking it is the first use of excreta, not the second time that it is used.Reuse of excreta is one example of resource recovery of the resources contained in excreta, mainly the plant-available nutrients nitrogen, phosphorus, potassium as well as micronutrients such as sulphur and organic matter. These resources which are contained in wastewater, excreta and greywater have traditionally been reused in agriculture in many countries and are still being reused in agriculture to this day, but the practice is often carried out in an unregulated and unsafe manner for example in many developing countries (e.g. Mexico, India, Bangladesh, Ghana). The WHO Guidelines from 2006 have set up a framework how this reuse can be done safely by following a multiple barrier approach.Excreta-based fertilisers vary in their general properties and fertilising characteristics and include the following types: urine, dried feces, composted feces, faecal sludge (septage), municipal wastewater, sewage sludge and animal manure. Reuse of sanitised excreta in agriculture has also been called a ""closing the loop"" approach for sanitation and agriculture and is central to the ecological sanitation approach.Reuse of excreta is the final step of the sanitation chain which starts with collection of excreta (by use of toilets) and continues with transport and treatment (wastewater treatment is one example) all the way to either disposal or reuse.