Linking China’s air pollution to export markets
As much as 10–40% of the air pollutants emitted in China’s Pearl River Delta region can be tied to exports, a new ES&T analysis shows.
As one of the world’s fastest growing industrial areas, the Pearl River Delta (PRD) region on China’s south coast churns out more than $100 billion worth of goods annually. Factory after factory produces inexpensive items, such as electronics, clothing, and toys, most of them destined for export to eager consumers in North America, Europe, and other parts of Asia. The dark side of this economic powerhouse is high levels of air pollution.
In a first-of-its-kind study posted today to ES&T’s Research ASAP website (DOI: 10.1021/es051275n), researchers found that a significant percentage of the SO2, NOx, and particulate matter (PM) in the air can be directly attributed to the production of exports. They also show that these emissions could be significantly cut back with fairly modest investments in pollution-control technologies.
“We in the West take advantage of cheap goods manufactured in China and other developing countries, and one reason they’re cheap is because there aren’t a lot of environmental controls,” says David Streets, an energy and environmental policy scientist at Argonne National Laboratory and the lead author of the study. “So we get the benefits of the cheap goods, and they absorb the air pollution; there’s something not quite right about that.”
The PRD region encompasses Hong Kong and parts of Guangdong Province, where PM levels have been measured at as much as 5 times the annual U.S. standard, notes Michael Bergin, an atmospheric scientist at the Georgia Institute of Technology and a study coauthor.
Bergin, Streets, and their colleagues from the University of Iowa and Zhongshan University (China) analyzed Guangdong provincial statistics and a detailed emissions inventory of various activities in the region to estimate the export-related emissions of four primary air pollutants: volatile organic compounds (VOCs), PM, NOx, and SO2. Sources include not only the manufacturing facilities but also the power plants that generate the electricity, the trucks that transport raw materials to the facilities and finished goods for export, and the ports and ships that handle overseas goods.
Overall, they found that 37% of the total SO2 emissions in the region, 28% of NOx, 24% of PM, and 8% of VOCs are caused by export-related activities. In the city of Shenzhen alone, which is the regional leader in industrial development and trade, a whopping 75% of the VOCs, 71% of PM, 91% of NOx, and 89% of SO2 emissions from the industrial sector were linked to export manufacturing. In 2005, Shenzhen housed 11 million people on 2000 square kilometers of land, as reported in the English-language newspaper China Daily.
The researchers also looked at an array of mitigation measures, such as placing emission controls on power plants and industrial smokestacks and upgrading motor-vehicle emissions standards, in a range of scenarios all the way to zero emissions. They found that ambient air quality could be improved by 5–30%, depending on the extent of controls adopted, at a cost of only 0.3–3.0% of the value of the goods produced. A $100 DVD player, for example, would only cost consumers $0.30 more after emissions controls were put in place, Streets points out.
“We have a tendency in the West to look upon what’s occurring in China and their pollution as something divorced from us and our activities,” notes Bill Chameides, chief scientist for Environmental Defense, a nonprofit advocacy group. This study “is a really interesting way of illustrating how the global economy links all of us in terms of environmental impacts.” He recommends that the study be extended to look at greenhouse gas emissions and be used as a basis for future international agreements on climate change.
The study’s findings also have implications for air-quality management in the PRD region, where China plans to double economic output over the next 10 years.
For the first time, “they’ve given us some hard numbers on what it would mean to clean up the air,” says Christine Loh, who is the executive officer of Civic Exchange, a nonprofit, independent public-policy think tank, and is a former Hong Kong legislator. “This should help people think through some of the policy adjustments that could be made in terms of what’s viable and could be done.”
The findings are also important from the U.S. EPA’s perspective, because air pollutants generated in China can impact U.S. air quality through long-range atmospheric transport over the Pacific Ocean, says Carey Jang, a senior environmental scientist in the agency’s Office of Air Quality Planning and Standards.
