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Prior to our technological age, human waste was often treated as a resource and thus taken out of the waste stream. Ancient Romans sold their urine to tanners and clothes washers (who transformed the urine into a more antiseptic ammonia). Solid waste was regularly used as a fertilizer in most cultures. Clearly the move to turn waste into a resource is nothing new.
What is different is what we have done with sewage in our technological age. We have treated sewage as something that is unclean that needs to be processed and released in nature to be transformed into something else. We don't treat it as a resource, we treat it as a waste for processing. We put scientists in charge at treatment plants to manage it and release personal responsibility to local governments for the handling of it. While some advanced sewage treatment plants try to turn waste into a resource, most do not.
The examples highlighted in the Nature article show us that we can find new ways, or return to old ways, of turning waste into a resource.