"The bureau has reinforced supervision and carries out regular inspections. We also encourage companies to upgrade technologies to reduce emissions."

Yan Caiming, general manager of Binhai-based coating supplier PPG Asia Pacific, said the company has invested nearly $10 million in two incinerators that can burn away more than 80 percent of the noxious gases generated during production.

"The flow of air enables airborne pollutants to travel a long distance and have a long-ranging effect on the local environment, so our facilities are not only beneficial to our frontline employees but also the district as a whole," she said.

Yan said the environmentally friendly waterborne automobile coating, which is usually more expensive than other types of products, used to be more welcomed by overseas auto manufacturers than domestic automakers.

"But in recent years we see more local customers, which I see as a gradual awakening of environmental awareness among Chinese companies," she said.

Yan said her company is looking to expand its production of auto waterborne coatings to meet the rising demand from the domestic market.