Selling human waste products as fertilizers became much less common after World War II, both for sanitary reasons and because of the proliferation of chemical fertilizers, and less than 1% is used for night soil fertilization.[clarification needed] The presence of the United States occupying force, by whom the use of human waste as fertilizer was seen as unhygienic and suspect, was also a contributing factor: "the Occupationaires condemned the practice, and tried to prevent their compatriots from eating vegetables and fruit from the local markets".[5]