Six people have received jail terms for up to five years for manufacturing and selling "gutter oil" in east China's Jiangxi province, according to a court ruling.

Wan Aimei, Wan Bin and Wan Jun, who founded Jiangxi Huanyu Biodiesel Co., Ltd in 2008, were guilty of buying substandard cooking oil and using it to manufacture oil for animal feed since 2010.

They sold about 1,000 tonnes of the oil between February 2011 and August 2011 and got about 7 million yuan (1.12 million U.S. dollars) from the sale.

They were sentenced from 2.5 years to five years in jail for the crime of producing and selling poisonous food, according to a Nanchang County People's Court ruling.

Zhang Shengfei, Zhao Junjian and Huang Xiaoxing, who managed a drinks manufacturer in south China's Guangdong Province, bought the oil from Jiangxi Huanyu Biodiesel Co., Ltd and sold 114 tonnes to cooking oil distributors.

They were given jail terms of between three and five years for the crime of selling poisonous food, according to the ruling.

The six defendants did not appeal their sentences in court.

"Gutter oil" refers to recycled oil made from kitchen waste dredged from gutters behind restaurants as well as inedible animal oil. The oil is dangerous if consumed, as it contains carcinogenic substances.

The use of "gutter oil" is a chronic problem in China.

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