A 2018 analysis of more than a century of literature found USC to be among the world’s most active institutions researching outdoor air pollution and respiratory health.

Researchers from Najah National University in Palestine assessed articles published in peer-reviewed journals from 1900 to 2017 to analyze trends in air pollution research, and identify influential researchers, countries and institutions in the field. The journal Multidisciplinary Respiratory Medicine published the findings in January.

USC ranked as the third institution with the highest research output, after Harvard University and the U.S. Environmental Protection Agency.

Over the 117-year analysis period, two of the top 10 most cited papers were co-authored by USC researchers in the Keck School of Medicine of USC Department of Preventive Medicine’s environmental health and biostatistics divisions as part of the Southern California Children’s Health Study. Faculty in the two divisions have led cutting edge research on air pollution since the study began in 1993. The divisions work together under the research umbrella of the Southern California Environmental Health Sciences Center and the Southern California Children’s Environmental Health Center.

The two frequently cited papers from the USC researchers demonstrated that air pollution increases the risk of asthma, and stunts the development of children’s lungs. These and other papers by the USC group were instrumental in supporting policies to reduce air pollution levels in southern California, according to W. James Gauderman, PhD, professor of preventive medicine and a member of the research team.

In follow-up research, the USC group showed that cleaner air over the past two decades has translated into significant improvements in children’s lung development and reductions in asthma-related symptoms. “This research is an environmental success story, with real benefits to our children’s health,” said Gauderman, who also directs the Department of Preventive Medicine’s division of biostatistics.

The analysis also noted a rapid increase in research regarding air pollution and respiratory health — but a gap in international, multidisciplinary research.

Conducting global research is often challenging, especially in low- and- middle-income countries, where the capacity to coordinate complex multi-disciplinary projects is limited.

“Paradoxically, air pollution is often more dangerous in these settings because more people rely on indoor burning for cooking and heating,” said Kiros Berhane, PhD, professor of preventive medicine and director of USC’s graduate programs in biostatistics and epidemiology.

To address this issue, USC is assisting research in eastern Africa, in partnership with Addis Ababa University in Ethiopia and with participation from scientists in Uganda, Kenya and Rwanda. The studies are designed after the Children’s Health Study in each of the four countries as part of the Global, Environmental and Occupational Health (GEOHealth) Hub for Eastern Africa – one of seven such hubs around the world funded by the Fogarty International Center of the National Institutes of Health, Canadian International Development Research Centre, National Institute of Environmental Health Sciences, and Centers for Disease Control and Prevention.

Despite the great progress in reducing air pollution over recent decades, problems persist in southern California, the United States and internationally. Los Angeles metro area, for example, continues to top the American Lung Association’s State of the Air report as the most polluted U.S. city for ozone.

“These adverse impacts are large and are totally preventable with science-based interventions and regulations,” said Frank Gilliland, MD, PhD, professor of preventive medicine.

But USC’s team remains committed, he said. “Our team of investigators will continue to do world-class research to provide the scientific knowledge about current and emerging exposures that is needed to protect people’s health now and into the future.”

— Larissa Puro