Chinese officials have arrested 32 people for the sale of the waste oil. The oil was purchases under the guise that it was to be used for producing biodiesel, and instead had been turning it into cooking oil and reselling it as such.
The business was extremely profitable, since the cost of buying the waste oil and refining it was so low.
After a 4 month investigation, officials found 6 places that sold the illegal oil and led to the arrest of the 32 people involved in the scandal.
Chinese authorities have called for tougher penalties, including the death penalty in serious food safety cases.