Fish vendors at Beijing's biggest seafood market have been using a dental treatment that is believed to have a tranquilising effect to help reduce fish deaths and injuries during transport, triggering more public concerns over food safety.
Many vendors pour zinc oxide eugenol cement, which is usually used for temporary dental fillings, into tanks before delivering fish to customers, China National Radio reported on Tuesday.
Although there is no scientific evidence that the practice could harm consumers, it is not a permitted food additive.
Vendors at Beijing Dahongmen Jingshen seafood market were quoted as saying that the cement, which usually sells for 12 yuan (HK$15) per 200 millilitre pack, helps to calm fish during the travelling, reducing the chance of injury from jumping and reducing death rates by at least 10 per cent.
Tong Yanjian, who mainly trades lobsters at the market, said that tranquilising fish during transport had been a common practice in the industry for years.
'Usually people add some tranquiliser to the water before transporting fish. This way the fish becomes quiet and won't hurt itself from jumping. When it arrives at the market, it revives and looks good,' he said.
He said that people used to use machines to add oxygen to the water during transport to prevent fish from dying, but adding chemicals was cheaper.