Food waste and the embedded phosphorus footprint in China

Abstract

The increasing food waste volume causes inadequate resource usage and results in partially avoidable environmental degradation. Although previous research has developed cost-effective processes for food waste treatment, the significance of embedded resources in food waste, especially the unreplaceable and depleting phosphorus, has been overlooked. This paper quantifies food waste in China at the provincial level by considering both at-home and away-from-home consumption, where phosphorus loss factor derived from substance flow analysis will be used to estimate phosphorus loss along the food supply chain. The results provide meaningful information regarding the volume and composition of food waste, as well as its impact on phosphorus resource and the environment at the provincial level. The calculation confirmed that at-table food waste was 53.7 million tons in 2015, while the embedded phosphorus was 86,300 tons. The off-table phosphorus loss was then back-calculated along the food supply chain, showing a total phosphorus loss of 424,400 tons, which was equivalent to 16.4% of the total mineral phosphate fertilizer consumption in China. Given China’s importance on the global food cycle, effective phosphorus management along the food supply chain, at-table food waste minimization and phosphorus recovery are recommended to close the current imbalanced phosphorus cycle.