Here is a timeline of notable food safety incidents in China:

2008: Six babies are killed and 300,000 others sickened after drinking milk formula is contaminated with an industrial chemical

Dumplings are discovered tainted with an insecticide

2010: Food sciences professor exposes recycled cooking oil taken from sewers outside restaurants

Green beans are found to be tainted with a pesticide

2011: 'Exploding' watermelons in eastern Jiangsu province are blamed on overuse of growth hormones

Hundreds are sickened in April after eating pork tainted with the steroid clenbuterol

Pork is contaminated with phosphorescent bacteria that causes meat to emit a blue light

Eleven people die and at least 120 are sickened after consuming vinegar tainted with anti-freeze