CCCEH Research: Chongqing, China
Begun in 2001 with support from the V. Kann Rasmussen Foundation, the China Study is using novel molecular epidemiology techniques to determine the health risks to children from environmental pollutants generated by burning coal and other fossil fuels. The study site is located in Tongliang County, China. The Tongliang Power Plant was located in the center of town and until recently was the only major source of air pollution in this urban area. It consumed more than 20,000 tons of coal per year and was not equipped with pollution reduction technology. Preliminary results from our Center’s work helped to convince the County and Chongqing Municipal Governments to shut down the power plant in 2004. This has made Tongliang an ideal site for studying the health effects of energy-related air pollution in children because these effects can be studied before and after the shut down. The aim of the study is to determine the health benefits to newborns of reducing in utero exposure to toxic air pollutants generated by coal burning. The research team is using geographic information systems (GIS) to link the research in China with ongoing CCCEH projects in the United States and Poland. The study is also policy-relevant, because information regarding health risks to children, as a sensitive population, is urgently needed to make sound decisions about energy use and health policy.
Pollution in China
China is one of the most populous nations in the world. Like many rapidly developing countries, China has relied heavily on coal-burning for low-cost energy production. However, the cost is being paid in human health. In China, coal-burning accounts for 70 percent of total energy production and releases large amounts of PAHs (polycyclic aromatic hydrocarbons), particulate matter, sulfur dioxide, and mercury. Air pollution from coal burning in China adversely affects the health of people throughout China and worldwide.
The United States Environmental Protection Agency recently estimated that 40 percent of mercury in the United States comes from power plant emissions overseas, especially coal-burning sources in China. China’s coal burning power plants are also a major source of carbon dioxide, the most important global warming gas. Coal-fired power plants in China currently produce 75 percent of the country’s electricity and the majority of new plants are being built to burn coal.
CCCEH Research in Chongqing
Chongqing, with a population of over 3 million, is one of the largest and most polluted cities in China due largely to coal combustion by industry and power plants. Our study of pregnant women and children living near the Tongliang power plant in Chongqing is the first molecular epidemiologic research in China to examine the effect of exposure during pregnancy to air pollutants from coal burning. This study is documenting the health benefits to babies and children of reducing PAHs in ambient air.
Study Methods — CCCEH scientists are documenting exposure, biomarkers, and health outcomes in three groups of babies and children whose mothers were enrolled into the study during pregnancy. One group of pregnant women, or “cohort,” was enrolled before the Tongliang power plant in the center of the city was shut down. The other two cohorts were enrolled after the energy conversion. Our study compares the health of children born to mothers who were exposed to high levels of air pollution during pregnancy when the plant was active, and mothers exposed to much lower levels of air pollution during pregnancy after the plant closed. Between birth and 5 years of age, children’s exposure to pollutants is measured repeatedly with air and biological samples, and children’s health is monitored annually.
Research Findings
Research results to date are demonstrating a critical health need for cleaner energy solutions.
- Newborns with high levels of prenatal exposure to air pollution from coal burning have smaller head circumference at birth and lower growth rate in childhood. Such early exposures can set the stage before a baby is even born for increased cancer risk, asthma, and cognitive delay, the effects of which can play out over an entire lifetime.
- Newborns in the first cohort (those who were in utero during operation of the coal burning power plant) had higher levels of DNA damage due to prenatal exposure to PAHs than newborns in either New York City or Krakow, Poland.
- Children with the highest estimated exposure to PAH from power plant emission had significantly worse performance on developmental tests at age two years.
- Respiratory problems are found to be more prevalent in children who were in utero while the power plant was operational.
As expected, our monitoring and biomarker analyses show significant reductions in air contaminants of concern (PAHs, mercury) since the plant shutdown in December 2004.
- Air monitoring collected as part of the CCCEH project prior to final plant shutdown showed ambient concentrations of benzo[a]pyrene in Tongliang, Chongqing were up to three and a half times higher during the power plant’s operational period than when the plant was not in operation.
- Levels of mercury in umbilical cord blood were significantly lower in babies born after the plant shutdown.
- Birth outcomes of the 2005 cohort collected after the power plant shutdown, were better the 2002 cohort in general, and head circumference size has improved significantly.
Policy Translation of Chongqing Study Results
CCCEH translates the results of this research so they are useful to both scientists and policy makers working to protect child health and develop sustainable energy policy. Working in partnership with Natural Resources Defense Council, our preliminary research findings helped convince governmental officials in China to shut down the Tongliang power plant and convert it to cleaner fuel technology. Our ongoing research findings are aiding China’s expansion of utility-based energy efficiency programs. Such changes are helping to decrease air pollution from coal burning which in turn improves the environmental health of children in China and other nations where coal-burning is prevalent, including the United States.
Our study results are informing policy initiatives worldwide that are substituting cleaner energy alternatives for fossil fuels in order to better sustain natural resources, slow global warming, and improve human health. CCCEH collaborates with the Natural Resources Defense Council’s Clean Energy Project and representatives of the Municipality of Chongqing, including the Chongqing Municipal Economic Commission, Environmental Protection Bureau, and the local health bureau.
- The Municipality is finalizing a plan to shut down its coal-fired plants and expand energy production using hydraulic power or natural gas.
- Scientific data from this project are being used to show government authorities in China the macro environmental, health, and economic benefits of adopting energy efficiency programs in Chongqing and other jurisdictions throughout China.
- CCCEH investigators and NRDC have co-authored an article in the Woodrow Wilson China Journal (China Environment Series 2007, Woodrow Wilson International Center for Scholars) which is widely read by policy makers.