NINGBO - Twenty people in China were given jail terms ranging from seven years to life for manufacturing and selling "gutter oil" in two provinces, a local court announced Tuesday.

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

Liu Liguo from the eastern province of Shandong was handed a life sentence after being convicted of "producing and selling hazardous and substandard food," according to a verdict from the Ningbo Intermediate People's Court in Zhejiang province.

Liu sold 99.9 million yuan ($16.2 million) worth of the unsafe edible oil made from kitchen waste between December 2007 and July 2011, the court found.

Six others who worked for Liu were sentenced to seven to 14 years in prison.

Bu Qingfeng from the central province of Henan was also sentenced to life in prison for "selling hazardous and substandard food," according to the verdict.

Bu earned 201 million yuan by selling "gutter oil" bought from Liu to food makers, pharmaceutical companies and feed producers between January 2010 and June 2011, the court found.

In a third case, Yuan Yi, a stall owner at a grain and oil market in Zhengzhou, capital city of Henan, was sentenced to 15 years in prison.

Yuan was convicted of selling 2.95 million yuan worth of "gutter oil" he purchased from Liu to construction-site canteens, roadside food stalls, and oil sellers, according to the verdict.

Eleven others who worked for Bu and Yuan were given jail terms ranging from seven to 15 years.

None of the defendants appealed their sentences in court.