BEIJING - China has set its pollution reduction targets for 2012, which include lowering both sulfur dioxide (SO2) and chemical oxygen demand (COD) by 2 percent and ammonia nitrogen by 1.5 percent, and maintaining zero-growth in the emission of nitrogen oxides.

The target was announced Wednesday at the National Environmental Protection Conference, which ran on December 20 and 21.

Minister of Environmental Protection Zhou Shengxian urged relentless efforts in cutting emissions of pollutants, and briefed the conference on progress achieved in fulfilling this year's emission reduction targets.

Zhou said emissions of SO2 and COD were estimated to have fallen by about 2 percent in 2011, exceeding the pre-set goal of 1.5 percent, but ammonia nitrogen emissions had only decreased by 0.9 percent while nitrogen oxide emissions rose by 7.2 percent.

Zhou also urged an early overhaul of the current air quality monitoring standard in order to address public complaints of underestimated air pollution by authorities. The revamp should include factoring in PM2.5, the measure of microscopic airborne particles, as well as measures of ozone and carbon monoxide into its pollution monitoring system.