Bo Ngoc Thu listed them as pulp and paper production, tapioca processing, rubber processing, production of basic chemicals, and leather tanning.

"These five sectors are allegedly the chief culprits that have caused severe pollution in the province in recent years," Dau Tu (Investment) newspaper quoted her as saying.

"So the government is ready to accept a certain reduction in investments to protect people's living environment.

"We will have great difficulty in cleaning up the environmental pollution if we continue to allow investors to invest in these sectors."

A spokesperson for the Dong Nai Industrial Park revealed that recently dozens of foreign businesses sought to invest in the park but had to be refused since the investments were in the five banned sectors.

Dong Nai authorities have also announced a list of sectors to invest in which investors have to meet certain conditions.

They are plating, spraying, metal polishing, dyeing, fertiliser production, fisheries processing, and production of paints, additives, and industrial laundry detergents.

Enterprises seeking to invest in these industries would have to operate in industrial parks and comply with regulations.

The province also gives priority to green and energy-saving projects and those in sectors like technology and supporting industries, new materials, information technology, agriculture, and processing.

This year the province hopes to attract US$1 billion in foreign direct investment, much lower than last year's figure of $1.6 billion. Domestic investment in the province is estimated at nearly VND7 trillion (US$329,473), down from VND8 trillion ($376,541) last year.

Increasing pollution

Dong Nai now has 31 IPs spread over a combined area of 9,838 hectares, of which 27 are operational and house 1,201 projects worth a cumulative US$16.6 billion. Of these, 872 are foreign-owned projects with a combined capital of $14.61 billion by investors from 36 countries and territories.

But despite making an important contribution to the country's socio-economic development, many companies also cause an adverse impact on the environment.

For instance, Vedan Viet Nam Monosodium Glutamate, a Taiwanese seasoning powder producer, was caught red-handed after discharging untreated wastewater into the Thi Vai River for several years. It had contributed to alarming levels of contamination in the river.

Sonadezi Long Thanh, a waste treatment company in the province was fined VND405 million ($19,000) for releasing poorly treated wastewater into the Dong Nai River.

Severe air pollution has also been observed at many IPs in Dong Nai, with pollutants exceeding permissible levels by one to nine times.

Provincial authorities took a series of drastic measures to combat the problem.

As a result, 120 out of 150 companies that had been placed in a list of serious polluters now have proper wastewater treatment facilities and have exited the list.

Lam Dong protects basin

The Central Highlands province of Lam Dong meanwhile says it needs about VND1.16 trillion (US$54.8 million) between 2014 and 2020 to protect the environment in a stretch of Dong Nai River basin running through the province.

The 586 km Dong Nai River runs through Lam Dong, Dak Lak, Binh Duong, Binh Phuoc, Long An, Tay Ninh, Binh Thuan and Dong Nai provinces and HCM City. In recent years, untreated wastewater from millions of households and thousands of factories has polluted the river basin.

Under a decision recently approved by Pham S, vice chairman of the provincial People's Committee, funding would be mobilised from the State and local budgets, official development assistance (ODA), non-governmental organisations and other sources.

The move aims to tackle water pollution and protect plant and animal life, S said.

By 2020, household wastewater treatment systems are set to be installed in Da Lat and Bao Loc cities and Lien Nghia town, while systems to treat industrial wastewater in Loc Son and Phu Hoi industrial zones will be complete. Systems to treat wastewater discharged from traditional medicine hospitals in Da Lat and Bao Loc are scheduled to be built by 2015.

S asked the provincial Natural Resources and Environment Department to finish an overall assessment identifying all pollution sources in the stretch of Dong Nai River basin running through the province by 2017.

A network of environmental observation stations along the stretch of the river basin was expected to be complete by 2020, he said.