Physicochemical properties and risk assessment of perishable waste primary products

Fertilization has become one of the most important ways to recycle perishable waste. In order to reveal the effect of the nutrient of the perishable waste primary products on the market and the possible impact of their application, 136 perishable waste primary products were sampled in nine cities in Zhejiang province, China. The result shows that these products have high nutrient content (average nutrient content was 5.00%). However, the conductivity (7.19 mS/cm) total soluble salt content (12.07%), and grease content (5.99%) were too high. The excessive salt and grease may cause harm to soil and crops, and become the main limiting factors for the fertilizer utilization of perishable waste. Heavy metal content of most of the samples met current commercial organic fertilizer standards, except that lead and chromium content of some samples exceeded the limit standard. Toluene, ethylbenzene, m & p-xylene were generally detected in the samples. These toxic and harmful substances have brought risks to the safe use of perishable waste into fertilizers.