To those who promote its use in agriculture the word is "biosolids", to those who fear its use it is "sewage sludge". Either way it has been the subject of much life cycle assessment over the years.
A fresh contribution to this subject has just been deposited in the journal Water Science and Technology (75(9):2013-2024): "Life cycle assessment of sludge management with phosphorus utilisation and improved hygienisation in Sweden".
Magdalena Svanström, expat Greg Peters and colleagues show that the differences in impacts between the different treatment technologies have more to do with the benefits water utilities can create by making byproducts, than by reducing impacts by directly reducing sludge treatment emissions.