BEIJING - The head of China's environmental watchdog said on Tuesday that 29 percent of cities in China lack treatment facilities for household refuse.

Minister of Environmental Protection Zhou Shengxian made the remarks at a bimonthly session of the Standing Committee of National People's Congress, China's top legislature.

Chemical oxygen demand (COD), sulfur dioxide and ammonium-nitrogen emissions continued on a downward trend in the first half of this year, but oxynitride emissions climbed by 6.17 percent, Zhou said, adding that China faces an arduous task in emissions reduction.