Wildfire Smoke Could Affect Pregnant Women Disproportionately

CALIFORNIA — Rachel Morello-Frosch co-authored one of the first studies looking at the effects of wildfire smoke on pregnant women in 2012. Today, she worries that the massive smoke plumes rising from California's largest ever fire season could be putting marginalized women at a higher risk.

Morello-Frosch, an environmental epidemiologist and a professor at UC Berkeley, studied the effects of wildfire smoke on pregnancy years ago, but little is actually known of the subject. She says researchers are now working to "play catch up" to identify how severe the effects actually could be for women across different communities.

"What keeps me up a lot a night is the effects on marginalized population groups, people who live in poorer quality housing or who work in jobs outside," Morello-Frosch said. "They don't have a lot of control in their ability to reduce their exposures."

In 2012, Morello-Frosch surveyed a data bank of all 2003 birth certificates across California, particularly looking at those who were born during the 2003 Southern California wildfires and whose mothers lived in smoke impacted areas.

She discovered that babies born during these circumstances had a difference in average birth term weight of about 7 grams less than babies born in areas that weren't polluted by smoke.

"At an individual level, it may not seem like a lot," she said. "But when you think about a population shift downward of 7 grams and a large number of people that were exposed to bad air quality...then it takes on more of a public health significance."

But babies aren't the only ones affected by polluted and smokey air. The U.S. Environmental Protections Agency says a number of physiological changes a woman undergoes during pregnancy can increase vulnerability to wildfire smoke, such as higher respiratory rates and increased blood and plasma volumes.

During wildfire season, hospitals tend to see more patients for respiratory issues, according to a study by University of California San Francisco. This is because the microscopic particles released by wildfire smoke can be inhaled deep into the lungs, according to Dr. John Balms, a professor of medicine at UCSF.

These particles can cause a range of health problems, from burning eyes and a runny nose to increased risk for chronic heart and lung diseases. Exposure to these particles has also been linked to premature death.

"The air quality issue is a concern for vulnerable groups of all sorts including pregnant women, especially when it lasts for a really long time," Morello-Frosch said. "And there is very good science that has shown the adverse affects of [unhealthy air] exposure on fetal growth among [pregnant] women who were exposed."

And while very little is known about the very specific impacts of wildfire smoke on pregnancy, even less is known of the possible impacts this heavily polluted air could be having on women who don't have access to the necessary protections from the smoke, or even the option to stay indoors.

"I am not optimistic that people are really thinking about that so much, about these vulnerable populations," she said. "The generational equity implications of these wildfire events on newborns and how that might impact them long term definitely worries me."

Throughout September, unprecedented levels of smoke choked the Golden State, plaguing countless Californians with chest pain, sore throats and a whole other buffet of side effects amid the COVID-19 pandemic.

And while some only reported mild symptoms, researchers at Stanford University found that between 1,200 and 3,000 California senior citizens died from wildfire smoke-related health conditions between Aug. 1 and Sept. 10.

Senior citizens and pregnant women were among populations listed as an "at-risk" and were advised by public health officials to stay inside, use an air purifier, wear an N95 mask while outdoors, or in some cases, flee.

"There's a broader issue here about the need to protect vulnerable people who don't have the capacity to do these individual actions," she said. "Many farm workers that are forced to work outside are women, and many of them could be pregnant — not to mention families that have to bring their kids to the field."

While the California Office of Emergency Services sent millions of N95 and surgical masks to agriculture commissioners across the state in May and again in September, Cal Matters reported that masks were still widely unavailable to farm works.

And Morrello-Frosch says that those protections alone may not be enough since the pay structure at many farm locations does not usually incentivize taking breaks or days off to take cover from heavily smokey days on shift.

"They're paid on a piece-meal rate so even if there's rules governing rest breaks, providing protective equipment and drinking water, the incentive is not there to use those opportunities to protect themselves because it's literally money out of their pockets," she said. "The pay structure discourages people from doing what they need to do to protect themselves and that includes women and pregnant women.

Instead, many farm works continue to toil in "horrible air," she said

"Those of us who are environmental epidemiologists are really trying to understand this better," she said. "I think as the data rolls in, there's going to be some concerning results from that work."

Rebecca J. Schmidt, a UC Davis researcher, has been working on a study that will help shed light on the affects of wood smoke from wildfires on on pregnant women. She's the leading scientist for the university's ongoing study called the Bio-Specimen Assessment of Fire Effects or B-SAFE.

The study has invited women who were pregnant during several major wildfires that have occurred over the last several years, including the deadliest and most destructive fire in California state history, the Camp Fire, which sparked Nov. 8, 2018.

The project is funded by the National Institute of Environmental Health Sciences and will soon be accepting participants who were pregnant during the 2020 wildfire season.

Although there is no definitive answer on the direct effects of wildfire smoke on pregnancy, a mother's exposure to wildfire smoke could harm a developing fetus, much like it can harm a young child's developing lungs, both the EPA and the CDC warned.

While the agency also acknowledges that there isn't an abundance of studies on the subject, there are studies on combustion-related air pollutants such as cigarette smoke and indoor biomass smoke that have confirmed that hampered air quality has a negative effect on pregnancy.

Morello-Frosch's co-authored findings of reduced birth weight were "slight," but researchers drew a similar line to pregnant women who smoke cigarettes; however, the affects were much less.

Women who smoke cigarettes during pregnancy typically have babies whose weight can be reduced by as much as 150 grams, according to UC Berkeley's study.

Regardless of these findings, both the Centers for Disease Control and the EPA have warned all populations about the dangers of wildfire smoke.

Smoke billowing from California's largest ever fire season shrouded the entire U.S. continent in mid-September, prompting widespread concern.

These fires have also unleashed record-breaking amounts of carbon dioxide and particulate-matter pollution into the atmosphere in both California and Oregon, according to multiple reports. The season has triggered the first increase in wildfire emissions in the U.S. since 2015, Bloomberg Green reported.

Health agencies urge anyone who lives close a wildfire burning to check at local air quality reports daily here.

The EPA also warns that surgical and cloth masks that are typically worn to protect against COVID-19, will not work for wildfire smoke. Particulate masks, N-95 or P-100 respirators will help if they fit well and are used correctly.

Most of all, people are advised to just stay home.

"Keep your windows and doors closed, unless it's extremely hot outside," the EPA said. "Run your air conditioner, if you have one. Keep the filter clean to prevent bringing additional smoke inside."