The sentencing on Tuesday comes just two weeks after a Chinese court handed down harsher sentences, including a suspended death penalty, to five people involved in producing and selling pork tainted with clenbuterol, a toxic chemical used to produce prized lean meat, underscoring the level of official and public concern over the scandal.

The seven, who had been selling clenbuterol to farmers since 2009, were also fined between 1,000 yuan ($156) and 28,000 yuan, the Xinhua report said.

Lean meat sells for a premium in China, the world's largest producer and consumer of pork, which spurs some farmers to resort to using clenbuterol.

If eaten excessively by humans, however, the chemical can lead to muscle tremors, dizziness, headaches and gastric irritations.

State media said clenbuterol-tainted pig feed had been distributed to eight provincial regions, including Henan, Shandong and Jiangsu provinces. State media named Henan Shuanghui Investment & Development Co Ltd, the country's top meat processor, as one of the main companies that had sold the contaminated pork.

China is no stranger to food safety scares, including one involving tainted milk, despite repeated government campaigns to crack down on the problem and tough punishments handed out to those involved.

Reuters