How does wildfire smoke affect pregnancy and children?

How does exposure to wildfire smoke affect pregnant women and their developing children? UC Davis Health researchers hope to answer that question with a new two-year, $1.35 million grant from the U.S. Environmental Protection Agency.

The study is led by molecular epidemiologist Rebecca J. Schmidt, assistant professor of public health sciences, and Miriam Nuno, professor of biostatistics.

Researchers are collecting birth and health records, as well as data on exposure to smoke from wildfires in California. They will look for links between wildfire smoke pollution and low birth weight, developmental delay and autism.

The team is also partnering with regional organizations to educate underserved communities about smoke exposure and suggest strategies to reduce exposure.

“This is a California study, but the entire country is exposed to wildfire smoke,” explained Schmidt, who is also a faculty member at the UC Davis MIND Institute, Center for the Perinatal Origins of Inequality (POD), and Environmental Health Sciences. Center. “It’s important to figure out what the real problems might be during pregnancy, including perhaps what times in pregnancy we need moms to be most careful about their exposure.”

Schmidt has experience studying the effects of wildfire smoke on pregnancy and children. Her previous research has included collecting hair, blood, and other samples from pregnant women and newborns. Her findings from this study will complement this new work.

It’s critical to figure out what the real problems might be during pregnancy, including perhaps what times in pregnancy we need moms to be most careful about their exposure.” —Rebecca J. Schmidt, Associate Professor, Public Health Sciences

Collection of data on smoke exposure, fertility and health

Wildfire seasons are getting longer and more severe. Wildfire smoke is estimated to be responsible for 339,000 premature deaths worldwide each year.

In California, where large-scale wildfires such as Camp, Kaldor and Dixie have affected both urban and rural areas, hundreds of thousands of pregnant women have been exposed to wildfire smoke.

“Studies have shown an association between wildfire smoke and lower birth weight or preterm birth, which are associated with later health outcomes,” Schmidt said.

The study focuses on four areas:

1. Find out which areas of California have experienced the most air pollution from wildfires.
2. Examine the effects of wildfire smoke before pregnancy and during each trimester of pregnancy. Researchers will look at these in relation to birth weight and gestational age, as well as factors such as neighborhood and local environment.
3. Explore links between wildfire smoke exposure, autism and developmental delay.
4. Work with community partners to share research findings and tools to help reduce smoke exposure for vulnerable populations.

“Our first step is to find out who is most affected by these recurring wildfires,” Schmidt explained. “Then we’ll look at how it depends on factors such as race, ethnicity, whether you live in a rural or urban area, poverty levels, and exposure to other pollutants.”

The study will include all people born in California between January 1, 2000 and December 31, 2021—approximately 11 million births. However, when looking at autism and developmental delay, the researchers will only include people older than 3 years by the end of 2021. Autism diagnosis is generally more reliable after this age.

The researchers will use state birth records, historical air monitor readings, and medical records from the California Department of Development.

Pregnant women experience stress due to the impact of wildfires, especially those who are more vulnerable. Justice calls for this information to be provided to these women.”—Miriam Nuno, Professor, Public Health Sciences

Empowerment of Vulnerable Populations

The study aims to identify vulnerable populations where people are exposed not only to wildfire smoke but also to other pollutants and pesticides and have less access to health care.

“Despite the fact that we are all exposed to smoke from forest fires, we all have different risks,” Nuno explained. “If you can work from home versus working outdoors, that’s where those differences really come into play.”

The researchers are collaborating with March of Dimes, Empower Yolo, and Knights Landing One Health Center, which provides medical care in rural areas of the Central Valley.

Together they will provide their findings and strategies to reduce the impact of wildfire smoke on underserved communities. This will include providing materials and training to help people make Corsi-Rosenthal airbags. It is an inexpensive filtration system that has proven effective in removing particulate matter from indoor air. Creator Richard L. Corsi, dean of the UC Davis College of Engineering, is a project partner.

“This project will advance solutions to issues at the intersection of climate change and environmental justice, both here in California and in communities across the country,” said EPA Pacific Southwest Regional Administrator Martha Guzman. “Advancing scientific research that helps protect public health and the environment is central to the EPA’s mission, and this project will have long-term results for years to come.”

Environmental justice is in the spotlight, says Nuno, who is also interim director of the Center for Health Policy and Research.

“Pregnant women are stressed by the impact of wildfires, especially those who are more vulnerable. Justice calls for this information to be provided to these women,” she said.

Other contributors include:

• Beate Ritz, professor of epidemiology, environmental health, and neuroscience at the University of California, Los Angeles.
• Irva Hertz-Picciotto, director of the Center for Environmental Health Sciences
• Katherine Conlon, Associate Professor, Department of Public Health Sciences and School of Veterinary Medicine, Department of Medicine and Epidemiology
• Michael Kliman, Professor of Civil and Environmental Engineering
• Sean Raffuz, Associate Director of Software and Data, UC Davis Air Quality Research Center
• Deborah Bennett, Professor, Department of Public Health Sciences
• Natalia Dib-Sossa, Professor of Chicana/o Studies

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