China's top environmental official said on Thursday the craze for growth among provincial governments might make new national anti-pollution targets difficult to achieve.

Two new pollutants - nitrogen oxides and ammonia nitrogen - will be included in the country's mandatory pollution control program between 2011 and 2015, while in 2011 the government hopes to achieve a 1.5-percent reduction for four major air and water pollutants.

The program currently manages emissions of sulfur dioxide and chemical oxygen demand, Minister of Environmental Protection Zhou Shengxian told a national work conference.

But the five-year targets are still awaiting approval from the National People's Congress, China's top legislature.

The recovery of the global economy and provincial governments' desire for major investment at the beginning of the 12th Five-Year Plan (2011-2015) period will become major challenges for the country's green campaign, Zhou said.

"Some provinces have set their annual economic growth target at 14 percent; you can imagine how much pollution that will bring," he said.

Although China's central government has put economic rebalancing high on its agenda for the next five years, with a lowered growth target in mind, most provinces are still aiming at 10 percent economic growth this year, with some even wanting to double economic output in the coming five years, local figures show.

Zhang Ping, who heads the National Development and Reform Commission, recently urged local governments to take into account the supply of "energy, environment, water and land" to set more reasonable growth targets.

Wu Changhua, Greater China director of The Climate Group in Beijing, said growth-obsessed practices at local level could lead to blind industrial expansion and might thwart the central leadership's pursuit of a more balanced and sustainable development model.

"When putting together the provincial targets, we find that the result is already much higher than the national plan. We have to find ways to curb this trend," said Wu.

Zhou also said it is essential to bring local development plans into line with national targets.

Some economists predicted the central government might bring down the annual growth target to 7 percent for the next five years from the current 10 percent.

Zhou said China had achieved a breakthrough in fighting pollution over the past five years, exceeding the 10-percent reduction target for water and air pollution.

Emissions of sulfur dioxide and chemical oxygen demand have dropped 14 percent and 12 percent respectively between 2006 and 2010, he said.

Zhou also vowed to establish a sound prevention mechanism to tackle the increased outbreaks of heavy-metal pollution accidents.

By 2015, the country will see an optimized industry structure for the heavy-metal sector, an emergency management system and an evaluation system on pollution and health risk, he said.

A nationwide plan to tackle heavy-metal pollution is waiting for approval from the State Council, which is likely to pass it this month, according to Zhou.

In a latest pollution accident, more than 200 children in Anhui province were tested for excessive levels of lead in their blood caused by pollution from a nearby battery factory.

The incident came after nationwide check-ups for heavy-metal producers, suggesting loopholes still exist in management, said Zhou.