1 Used as feed to feed livestock, commonly known as "swill pig". Untreated kitchen waste may contain foot-and-mouth disease, swine fever, Toxoplasma gondii, Salmonella, Trichinella spiralis and Campylobacter. If it is directly used to raise livestock and poultry, it will pose a great threat to the health of livestock and poultry. It may bring harm to human health through the accumulation of toxins and harmful substances in livestock and poultry, thus causing cross-infection between humans and animals. Therefore, this form of food chain connection hides the great threat of pathogen transfer and non-proliferation.

Waste edible oil has caused a series of hazards. The extracted gutter oil will contain impurities and be polluted by aflatoxin, benzene and other toxic substances. Long-term consumption will cause chronic diseases such as tumors, such as stomach tumors and liver tumors. If left unchecked, waste oil will have complex biochemical reactions in water. A series of malodorous substances such as aldehydes and acids with complex components are produced, and the odor of these malodorous substances is emitted into the air, which pollutes the atmosphere and deteriorates the living environment. Waste oil blocked the sewage pipeline, causing sewage to flow backwards. Waste cooking oil pollutes groundwater, consumes oxygen in water, causes eutrophication of water, breeds mosquitoes, flies and other pests to abandon edible oil and flow into rivers, which easily leads to hypoxia and suffocation of fish and shrimp.

3. Affect the city appearance and living environment. In terms of sensory characteristics, kitchen waste is greasy and humid, which affects people's visual and olfactory comfort and life hygiene. The high moisture content and organic components make it a "natural paradise" for microorganisms to exist. At the same time, due to the high moisture content, it is difficult to transport garbage without treatment. In addition, food waste will increase the generation of landfill gas and the precipitation of leachate, thus polluting the surface and groundwater.