Present state of food and feed cycle and accompanying issues around Japan

Nitrogen (N) and phosphorus (P) cycles of food and feed, and the regulation systems for industrial wastewater are studied. The rate of domestic supply of food in Japan is 41% in 1970, 32% in 1990, and 29% in 1998 for N and 33%, 29%, and 28% for P, excluding grass feed. Among 3 countries, Japan, USA and Thailand, Japan is in the most difficult state to recycle food wastes to farmland. Comparing the estimated load of wastewater from food processing industries with the estimated load according to the budget study for N and P cycles, the tentative criteria of wastewater of food processing for P seem to be loose, and de-nitrification might be considered in every stage of N cycles. New regulation of industrial wastewater recently proposed in Japan may induce the chance for environmental business to remove N and P.