Chinese police have seized more than 30,000 tonnes of tainted chicken feet and arrested 38 people involved in the sale, as the country's food woes continue to grow.

Chicken feet, one of the favourite snacks in China, are common on restaurant menus in the country. They are often broiled or put in soups.

The food products contaminated with hydrogen peroxide were seized from different provinces in the country, including the eastern province of Zhejiang, the official Xinhua news agency reported.

The police have raided and sealed nine factories in the provinces of Jiangsu, Anhui, Henan and Guangdong, Xinhua said. They are still hunting for 11 suspects.

The factories used hydrogen peroxide solutions as bleach and antiseptics, making the food item poisonous. Hydrogen peroxide is widely used in manufacturing and medical sectors as a disinfectant and bleach, but its use in food products could be detrimental to health.

The chemical, which causes health problems if consumed, may have been used to give the chicken feet a whiter, cleaner appearance.

Food safety has been a serious issue in China ever since the 2008 milk scandal when infants fell ill or died after consuming tainted milk powder.

Earlier in August, US ketchup maker HJ Heinz Co apologised to Chinese consumers after recalling some infant cereal due to excess levels of lead.

In July, Shanghai Husi Food, owned by US-based food supplier OSI Group LLC, was found to have sold chicken and beef past their expiry date to international food chains including McDonald's, KFC and Pizza Hut.

Subsequently, KFC and McDonald's said they stopped using products from the supplier, and apologised to Chinese consumers for the issue.

This is not the first time chicken feet are at the centre of a food scandal in China. In July 2013, police seized 20 tonnes of badly expired chicken feet – some of them as old as 46 years – from a warehouse.