Air Date: Week of July 18, 2008

In 2004, the Chinese government shut down an old coal-fired power plant in the city of Tongliang. It afforded researchers the perfect opportunity to study the developmental effects of exposure to air pollutants both while the plant was running and immediately after it was shut down. Dr. Frederica Perera is the lead author of the study, and Director of the Columbia Center for Children’s Environmental Health.

Transcript

GELLERMAN: It’s Living on Earth, I’m Bruce Gellerman.

In 2004 Chinese Government shut down a coal-fired power plant in the Midwestern city of Tongliang. The plant closing provided researchers with a unique opportunity to study the effects of the coal pollution on the development of children in the area. Doctors Deliang Tang and Frederica Perera with the Columbia Center for Children’s Environmental Health conducted the research in China. Their study now appears in the latest edition of Environmental Health Perspectives. Dr. Perera is the Director of the Center. And Dr Perera –seems you got lucky with the closing of this coal-fired power plant.

PERERA: We certainly did. These are rare opportunities where one can actually study and measure the benefits of an intervention—in this case, the closure of a polluting coal-fired power plant. And that allowed us to enroll one group of pregnant mothers and their babies and follow them for several years and then enroll a second group after the plant had been shut down and compare their exposures and their developmental outcomes.

GELLERMAN: So what did you find?

PERERA: Well when the babies were more exposed they had higher levels of the pollutants in their umbilical cord blood and they fared less well on the developmental tests at age two, particularly in the motor area. And we’re certainly not talking about loss of IQ points here but the test is intended to detect children who are intellectually at risk and in need of remediation to avoid later problems in academic performance.

GELLERMAN: How significant were the differences in these two groups of children?

PERERA: There was a 40 percent reduction in the level of exposure as we measured it and a 60 percent reduction in the frequency of developmental delay in the motor area.

GELLERMAN: What pollutants were you looking at specifically?

PERERA: Oh specifically we’re looking at the polycyclic aromatic hydrocarbons. And these are known as PAHs. They are very common combustion products from coal burning and burning of other organic material. And they do many things. They’re known carcinogens as well as developmental toxicants.

GELLERMAN: How polluting was this power plant that closed down?

PERERA: Well the power plant was fairly polluting. It burned 25,000 tons of coal a year. It emitted particulates and SO2 at a rate exceeding the US standard certainly and the Chinese standards and that was the reason why the government had ordered shutdown not only this plant but of the entire category of the older power plants.

GELLERMAN: What about these new modern coal fired power plants that China’s now building?

PERERA: Well I think these newer power plants will certainly be less polluting than the one we were studying, no question about it. And of course one can’t directly extrapolate from one study in a setting such as the one we had here to others but I can say though that in our studies in other countries in the U.S. and in Poland at lower levels of exposure than we were measuring here in China we could detect significant effects on early child development as well as on fetal growth.

So we take from that that there is no apparent threshold or safe level of exposure to these pollutants. So that as we infer that as one reduces the level of exposure to these contaminants, one will see benefits in terms of child health and development.

GELERMAN: Of course China’s producing three-quarters of its electricity from coal-fired power plants.

FERERA: That’s correct. I think China as well as many other countries are working very hard now to achieve more independence from fossil fuel and also to switch to renewables and efficient utilization of energy but in the meantime I hope that our study will be helpful in showing the good news from an action by a government and recording that benefit in terms of child health.

GELLERMAN: Dr. Frederica Perera is Director for the Columbia Center for Children’s Environmental Health. Well Dr. Perera I want to thank you very much.

PERERA: You’re most welcome.

 

Links

To read Federica Perera's study, click here

Fore more on coal, check out Living on Earth's series "Generating Controversy"