Gutter oil is a dim, turbid and reddish paste. These foul-smelling garbage can be turned into clear "edible oil" after only one night of filtration, heating, precipitation and separation, and finally returned to people's dining tables through low-price sales. This three-no product, called "waste oil", is still composed of triglycerides, but there are many more toxic substances that cause disease and cancer than real edible oil.

In the process of refining "gutter oil", a series of chemical changes, such as rancidity, oxidation and decomposition, occur after animal and vegetable oils are polluted, resulting in substances that are highly toxic to human body; Arsenic is one of them;

. "Waste edible oil" is a refined oil made from swill (swill, leftovers, etc.). ) and waste edible oil collected from hotels and restaurants to remove odor and flow to the edible oil market. Waste oil contains aflatoxin and benzopyrene, both of which are carcinogens.