The argument over whether producers should use flour bleach is not new. It first began about a decade ago.

There is no unified international standard on whether to use bleach, or how much to use.

The only function of BPO is to make flour have a better look.

Critics of its use say BPO, or flour bleach, can destroy the nutritional structure of flour, and has the potential harm the liver.

Experts say something contained in BPO could lead to liver failure. Healthy people will suffer benzene poisoning, and feel nervous, dizzy and weak if they eat bleached flour often enough for a long period of time.

They argue it should be forbidden because it does nothing but harm people's health.

Advocates say the argument against BPO is the result of business competition. Smaller factories usually overuse the bleacher to make flour appear whiter, and therefor increase the perception it is better, in order to enlarge sales.

Wang Yongxiang, supermarket employee, said, "Old people usually see brands and they like whiter ones."

Advocates also believe more serious food security problems will appear if BPO is forbidden. Some small companies producing products with flour may add something more poisonous to make their products look more attractive.

Chen Rui, vice-director of Food Security Control Bureau, Ministry of Health, said, "There are a lot of different opinions. We have to do much research on this issue. The new Food Security Law will place strict requirements on food security, so we need to do plenty of work before we make rules."

The recently published notice by the Ministry of Health says relevant bleacher inspection measures will be done to ensure food security regulations are being followed once BPO is prohibited.