Experts test the water quality at Taiyuan monitoring centre, part of the national water quality monitoring network, in north China's Shanxi province on June 30, 2007. (Xinhua Photo)

    BEIJING, June 30 (Xinhua) -- China's new national standard for drinking-water quality will take effect as from Sunday to ensure clean tap water supply to the country's urban and rural residents.

    "In some of China's cities, water supply has been contaminated and residents are threatened with unsafe water," said Zhang Chengyu, an official with the Ministry of Health.

    The current standard, issued in 1985, are out-dated and can not protect citizens from health hazards, said Zhang.

    The new standard will raise the quality of tap water in terms of organism, microorganism and disinfection by bringing 71 more quality indicators into monitoring in addition to the original 35 indicators, he said.

    They will also ensure an uniform standard on urban and rural areas.

    The new standard, according to Zhang, were prepared with reference to World Health Organization's guidelines for drinking-water quality.