A total of 134 people in Shandong Province were arrested last year for producing and selling gutter oil.
A total of 19 people have been prosecuted, with 12 officials losing their positions for dereliction of duty, said Zhou Yuhua, head of the Shandong Provincial Higher People's Court. In one case, two people were sentenced to 10 years in prison for selling more than 110 tons of gutter oil, an illegal food additive made by processing used vegetable oil.
Scientists said that it is difficult to test for the substance, as profiteers have already become sophisticated enough to fool the inspectors.