Jia Youling, China's chief veterinarian at the country's Ministry of Agriculture said that some farmers still use banned growth-enhancing drugs, food coloring and other chemicals, which continue to harm consumers, while feed additives with high concentrations of metal pollute water and crops.

According to Bllomberg news agency he said that food safety is a government priority after tainted products harmed consumers around the world as China prepares to host the Beijing Olympic Games. Pet food, toothpaste, seafood and frozen dumplings have been recalled in the U.S., Japan and the EU after toxic chemicals were found in ingredients and raw materials.

"Cases of illegal drug use still exist, potentially contaminating animal products and endangering public health," Jia said. A significant number of farmers use additives with heavy metals, which accumulate in animal feces and "pose a serious risk of polluting soil and crops," Bloomberg heard.

Rising incomes and better diets have fueled growth in meat, dairy and seafood production. Rapid expansion, intense competition and cases of inadequate quality control have increased the risk to food safety.