The State Environmental Protection Administration (SEPA) has warned that China's efforts to hold acid rain and sulfur dioxide (SO₂) at bay will fail if no further action is taken.

It estimates that the country will discharge 28 million tons of SO₂ in 2020, 16 million tons more than the amount the country's environment can accommodate.

The damage to the environment and human health caused by acid rain and SO₂ pollution translates into economic losses of 110 billion yuan (US$13.3 billion) annually.

Such losses will increase continuously, officials said.

In 1995 the country designated major regions with high SO₂ emissions and serious acid rain pollution as "two controls" regions.

The designated regions include Beijing, Shanghai and 21 provincial capitals, covering nearly 1.1 million square kilometers. Most are developed regions.

SO₂ irritates the respiratory organs and inhalation of high-density sulfur dioxide can cause laryngeal edema and bronchitis.

Acid rain, meaning precipitation with a pH lower than 5.6, can erode buildings and harm crops. It can also lead to diseases like lung edema. Pure water has a pH of 7.0, while normal rain has a pH of 5.6.

SEPA reports that overall discharge of SO₂ in the "two controls" regions dropped from 13.2 million tons in 2000 to about 11.5 million tons in 2002, while total SO₂ discharge nationwide dropped from 19.9 million tons in 2000 to 19.3 million tons in 2002.

However, last year saw a significant increase in coal consumption, from 1.4 billion tons in 2002 to 1.6 billion tons. As a result, SO₂ emissions in the "two controls" regions and in the whole country jumped to 13.3 million tons and 22.2 million tons, respectively.

At the same time, acid rain in some regions worsened last year. Within the "two controls" regions, 16.5 percent of the cities reported precipitation with a pH lower than 4.5, an increase of 12.6 percent from 2000.

In some cities, including Zhejiang Province's Shaoxing and Ningbo, acid rain accounted for more than 90 percent of total precipitation last year.

"In recent years, acid rain has been more and more serious in Ningbo," said a chief engineer of the Ningbo Environment Monitoring Center, who only gave his surname, Xu.

Xu attributed the phenomenon to the industrial sector in the city, especially coal-fueled power plants, few of which are equipped with adequate desulfurization facilities because of the high cost.

"They would rather be fined than buy such expensive facilities," he said.

SEPA Vice Minister Wang Jirong said the main hurdles for SO₂ and acid rain control lie in the country's excessive demand for energy, failure to build enough pollution treatment projects and a large number of small coal-burning power plants.

Economic growth and need for energy have surpassed expectations, she said.

Current development trends indicate coal consumption in the country will exceed 1.8 billion tons in 2005, 400 million tons more than expected.

That would add another 6 million tons of SO₂ emissions nationwide in 2005. The "two controls" regions would see more than 3 million tons of additional SO₂ discharge.

At the same time, pollution treatment projects are being constructed at a very slow pace, Wang said.

The country's 10th Five-Year Plan (2001 - 2005) calls for 279 SO₂ control projects to be constructed during the period, which would reduce SO₂ discharge by more than 3 million tons each year.

However, by 2003, only 61 projects had been completed and 72 were under construction. Another 89 are in the initial design or feasibility study stages, while 57 have not been launched at all.

In addition, the power supply shortage caused a delay in the plan to shut down small coal-burning power generators by the end of last year. In fact, some power generation facilities that had been shut down resumed operation.

Wang said that SEPA will strengthen supervision and management so that SO₂ discharge can be minimized.

More effort will be made to ensure that 80 percent of the planned pollution treatment projects are built and put into operation and more coal-burning power plants are equipped with desulfurization facilities.

(China Daily April 27, 2004)