BEIJING -- With Chinese factories discharging more and more sulfur dioxide, one third of China's territory was bathed in acid rain last year, according to a parliamentary report.

More than half the 696 Chinese cities and counties monitored had experienced acid rain. In some regions, every rainy day was an acid rain day, according to the pollution control inspection report released by the country's top legislature on Saturday.

The report was based on lawmakers' recent inspection of environmental protection efforts in 15 provinces, autonomous regions and municipalities, and was submitted to the Standing Committee of the National People's Congress (NPC) for review on Saturday.

With 25.49 million tons of sulfur dioxide discharged in 2005 - 27 percent more than in 2000 - China has become the world's biggest sulfur dioxide polluter.

"Increased sulfur dioxide emissions meant that one third of China's territory was affected by acid rain, posing a major threat to soil and food safety," said Sheng Huaren, vice-chairman of the NPC Standing Committee, when briefing lawmakers on the report.

He said the sulfur dioxide emissions doubled the acceptable environmental limit. Coal-burning power stations and coking plants were the main culprits.

According to the report's findings, nearly 650 out of 680 coking plants in Shanxi, the country's major coal mining province, discharged excessive sulfur dioxide.

"In 40 percent of Chinese cities the air is polluted, mainly by sulfur dioxide and particulates suspended in the air," Sheng said.

Smoke and industrial dust emissions also increased in 2005, despite the government's vow to reduce the emissions by 9 percent annually, the report said.

Sheng said the deteriorating environment was the price local governments paid for the headlong pursuit of economic growth, acknowledging that many localities set economic growth targets of over 7.5 percent.

"It is especially worrying that most local governments base economic growth on energy consuming industries, disregarding the environment's capacity to sustain industrial expansion," Sheng said.

Environmental inspectors recommend that the central government take decisive action to curb high energy consuming and polluting business by restricting land approvals and loans while simultaneously raising pollution control standards, Sheng said.

"Small coking plants and coal-burning power stations should be shut down or restructured," he said.