via composting. The safe reduction of human excreta into compost is possible. Some municipalities create compost from the sewage sludge, but then recommend that it only be used on flower beds, not vegetable gardens. Some claim that this is dangerous or inappropriate without the expensive removal of heavy metals. History Ancient Attica The use of sewage as fertilizer was common in ancient Attica. The sewage system of ancient Athens collected the sewage of the city in a large reservoir and then channelled it to the Cephissus river valley for use as fertilizer. China, Hong Kong, and Singapore The term is known, or even infamous, among the generations that were born in parts of China or Chinatowns (depending on the development of the infrastructure) before 1960. Post-World War II Chinatown, Singapore, before the independence of Singapore, utilized night-soil collection as a primary means of waste disposal, especially as much of the infrastructure was damaged and took a long time to rebuild following the Battle of Singapore and subsequent Japanese Occupation of Singapore. Following the development of the economy and the standard of living after independence, the night soil system in Singapore is now merely a curious anecdote from the time of colonial rule when new systems developed. The collection method is generally very manual and heavily relies on close human contact with the waste. During the Nationalist era when the Kuomintang ruled mainland China, as well as Chinatown in Singapore, the night soil collector usually arrived with spare and relatively empty honey buckets to exchange for the full honey buckets. The method of transporting the honey buckets from individual households to collection centers was very similar to delivering water supplies by an unskilled laborer, with the exception that the item being transported was not at all potable and it was being delivered from the household, rather than to the household. The collector would hang full honey buckets onto each end of a pole he carried on his shoulder and then proceeded to carry it through the streets until he reached the collection point. Chinese has a similar euphemism for night soil collection, dàoyèxiāng, which literally means "emptying nocturnal fragrance". Japan The reuse of feces as fertilizer was common in Japan. In the city of Edo, compost merchants gathered feces to sell to farmers. That was good additional income for apartment owners. Human excreta of rich people were sold at higher prices