Despite assurances of environmental safety, experts and locals alike are wary about a petrochemical plant planned for west China's Three Gorges Reservoir area.

"I suggest holding a referendum, as this kind of project cannot be decided by a small group of people," said a netizen named Jialin from Shanghai.

BASF, the German petrochemical giant, said yesterday it expected the Chongqing petrochemical plant to be approved by the Chinese government before the end of 2009.

Earlier reports by the 21st Century Economy Herald said it was to be located in Changshou district, a petrochemical industry park in Chongqing municipality that is within 3 km of a densely populated area and the river head for more than 70,000 local residents.

"The industrial park is already sending out a nauseous smell. Being healthy is much more important than money for citizens," a netizen named Meng Mei from Chongqing said.

When finished, the project will be one of the world's largest methylene diphenyl diisocyanate (MDI) plants.

MDI is an allergen. People developing sensitivity to the chemical may have dangerous reactions, including respiratory failure, to even an extremely small exposure.

About 400 million people in six provinces and the city of Shanghai live downstream from the plant, drawing most of their water from the Yangtze River.

The company said yesterday that final approval of the project by Chinese regulators is expected this year.

Capable of producing 400,000 tons of MDI annually, the plant is targeted for completion in 2013 and commercial operation by 2014.

"It is quite normal for public concern to be aroused by this project, but if BASF gets the final approval, it must meet extremely strict national requirements," said Shang Hongbo, an official from the policy research center of the Ministry of Environmental Protection.

"The ministry will make the decision very carefully, especially since the project is located in the Three Gorges Reservoir area," he said.

There has also been criticism from experts, who say there is no precedent for building an MDI project near such an upstream reservoir, warning the production procedure is highly toxic and needs a very large buffer zone.

Melanie Maas-Brunner, group vice-president of BASF Polyurethanes Asia Pacific, said that a strong commitment to environmental protection is a necessary precondition for any project like this.

Maas-Brunner said BASF operates world-scale MDI plants in many other countries, such as Belgium and the United States. But this has not been enough to comfort people.

Jiang Wenju, a professor with the petrochemical institute of Sichuan University, said no petrochemical program in the world is "absolutely safe".

"It is the contradiction between economic benefit and environmental protection. I can't tell you how dangerous the project is, but strict technological requirements and sufficient information disclosure are definitely necessary," he said.