Rice dumplings sold during the Dragon Boat festival will soon have to comply with an official 'national standard' for both content and appearance, the Beijing News said yesterday. A key element of the new regulations would be a ban on additives on the bamboo leaves used for wrapping the dumplings, the paper quoted an expert as saying. The expert was reported to have taken part in the drafting of the new law. Some vendors add chemicals to the bamboo leaves before cooking to retain the fresh green appearance of the dumplings. The ingredients used in the dumplings depend on the region, but the ratio of glutinous rice and other staples within a dumpling will be stipulated in detail. Hygiene standards would be clearly spelled out and strictly enforced, the expert added.