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Wendy Klag Center for Autism & Developmental Disabilities

Autism and Air Quality in China

Strict pollution controls for 2008 Beijing Olympics created unique natural experiment

smoggy 2008 Olympic park in Beijing China

Olympic Park, pictured in 2008, during a period of restricted emissions.                                      Alan Phillips/Getty Images

Researchers at the Johns Hopkins Bloomberg School of Public Health will lead an autism research study in Beijing, China, that explores the neurologic development of children born around the 2008 Beijing Olympics, when air pollution was tightly controlled.  Li-Ching Lee, PhD, ScM, a psychiatric epidemiologist with the Bloomberg School’s Departments of Epidemiology and Mental Health, was the original principal investigator for the five-year, $2.8 million China project. Upon Lee's death in 2021, the project leaders became Christine Ladd-Acosta, PhD, of JHSPH and Junfeng Zhang, PhD, of Duke University.  The project is funded by the National Institutes of Health. The study will explore the potential for reducing early-life air pollution exposure as a public-health intervention to reduce risk for autism spectrum disorder (ASD).

China took major steps to improve air quality for the Olympic and Paralympic Games, ordering industries to cut emissions and restricting auto traffic July 20 to Sept. 19, 2008. The Olympic Games ran from Aug. 8-24, and the Paralympic Games ran from Sept. 6-17. Pollution control measures ended Sept. 19, 2008. Prior studies from the United States and Europe suggest that prenatal air pollution exposure and exposure during early infancy increase risk for ASD.

“The findings of this study, which has a unique study design coupled with a historical intervention that drastically affected exposure, are expected to improve our understanding about a potential causal relationship between prenatal air quality and autism,” Lee said when project funding was announced.

Investigators will estimate the prevalence of ASD in Beijing among children who were in utero before, during and after the Olympic period. This will involve screening more than 18,000 children born in the months before and nearly a year after the temporary pollution controls. Researchers also will assess time-window-specific effects of prenatal air pollution exposure. For example, did children who were in utero during a specific trimester of the cleaner-air period have lower risk for ASD?

Lee, who was an associate director of the Wendy Klag Center for Autism and Developmental Disabilities at the Bloomberg School, was an expert in global autism research whose work often took her many time zones away. She also was a longtime principal investigator on estimating autism prevalence in the United States.

Other collaborating institutions of this project include Peking University in China, as well as Emory University and Duke University in the United States.

The study is funded by the National Institute of Environmental Health Sciences, part of NIH.

A delegation of Chinese psychiatrists visited Johns Hopkins Bloomberg School of Public Health as part of an autism air pollution study.     JHU air pollution team

A five-member delegation of top psychiatrists from China visited JHSPH in December 2019 as part of their role in a joint research project exploring autism and air pollution. The project team from Peking University and JHSPH are (left to right) Xue Li, MD, PhD; Yanqing Guo, MD; Peng-Chou Tsai, MD; Li Yang, MD, PhD; Yufeng Wang, MD; PhD; Li-Ching Lee, PhD; Aniket Kini, MD; Heather Volk, PhD; and Jing Liu, MD, PhD.  The photo at the right shows JHU team members Peng-Cho Tsai, MD, and Chris Ladd-Acosta, who replaced Li-Ching Lee as a principal investigator.