Wildfire smoke increases the risk of preterm birth: research

Exposure to wildfire smoke during pregnancy increases the risk of preterm birth. The risk is exacerbated, a new study from Stanford University found.

the study, Published in Environmental ResearchThe addition of 7,000 preterm births in California may have been due to exposure to wildfire smoke between 2007 and 2012. According to the author, preterm birth occurs 37 weeks before gestation, with incomplete fetal development leading to neurodevelopment, gastrointestinal and respiratory complications, and death.

During the smokeiest season featured in the 2008 survey, the authors found that wildfires could have contributed to more than 6% of preterm births. That year, heavy thunderstorms, strong winds and high temperatures combined Set a stage with particularly severe conditions, Said a news release accompanying the study.

However, according to study co-author Marshall Burke, the devastation that occurred in 2008 already outweighed the devastation in 2020, when smoke exposure was 2.5 times worse than in 2008. And the authors are afraid that this phenomenon will repeat in 2021.

“2020 doesn’t look that unusual because of what we expect in the future,” Burke, an environmental economist at Stanford University, told Hill. “Unfortunately, we need to think of it as a new common sense.”

California is working on one of the worst wildfire seasons in history. Dixie Fire, northeast of San Francisco, It was still expanding after 5 weeks As of Sunday, only 37 percent were included, according to the Associated Press. According to AP, the Caldor fire on August 14 burned the Sierra Nevada Mountains, with zero containment by Sunday, but only 10% of the French fire in Southern California.

These fires are destroying what is still moving CalFire is called “2020 Fire Siege” It burned about 4 million acres and caused some of the worst daily air pollution ever recorded in California.

Wildfire smoke is especially dangerous due to the high levels of PM 2.5 — particulate matter 2.5 micrometers in diameter, or 1/30 of the diameter of a single human hair, According to the Environmental Protection Agency. These particles can penetrate deep into the lungs, and sometimes even into the bloodstream, the EPA said.

A Stanford University study builds on an established link between particle contamination and the adverse effects of childbirth, but this is the first time a news release has identified the effects of wildfire smoke on preterm birth.

To establish this correlation, the author analyzed smoke plume satellite data from the US National Oceanic and Atmospheric Administration with 2,610 zip codes in the 2007-2012 window. The data was then developed using machine learning algorithms that fuse data from air quality sensors, satellite observations, and computer models that track how pollutants move through the atmosphere. Combined with level PM2.5 contamination estimates.

According to the news release, preterm birth data was taken from California birth records, excluding multiples of twins and above that generally arrive early due to other factors. After considering other factors related to preterm birth risk, the author investigated how such birth patterns at each zip code change with a surge in smoke days and intensity.

“We see amazing consistency across households,” Burke told Hill.

Ultimately, the authors found that daily smoke exposure during pregnancy increased the risk of preterm birth, regardless of race, ethnicity, or income, the news release said. Weekly exposure meant a 3.4% higher risk compared to mothers who had not experienced wildfire smoke exposure, but the greatest effects occurred during the second trimester.

According to a news release, scientists have not yet determined the exact health effects of wildfire smoke. Wildfire smoke has a different chemical composition than other PM2.5 sources such as agriculture, tailpipe emissions and industry.

However, according to the author, one potential explanation for the surge in preterm birth is that smoke can trigger an inflammatory response that initiates the labor process. They acknowledged that this risk was small compared to other factors that contributed to health and maturity.

“But finding clues like this here against a background where we know very little about why some women give birth too early, prematurely, and others don’t. It helps us stitch together larger puzzles, “co-author Gary Shaw, a professor of pediatrics and co-principal researcher at the March of Dimes Premature Infant Research Center at Stanford University, said in a news release.

Sam Heftneil, lead author and researcher at Stanford University’s Center for Food Security and the Environment, said that “due to the confluence of factors” such as climate change and fire, heavy exposure to such smoke will increase in the future. I warned you to continue. Suppression.

“As a result, exposure to smoke, including preterm birth, is likely to increase the health burden,” Heftneil said in a news release.

According to Shaw, the short-term solution for pregnant women is to stay indoors or wear a suitable mask outdoors. In the long run, the authors said their work demonstrates the value of wildfire mitigation investments such as open burning and thinning.

“There is a lot of evidence that open burning is a cheap way to reduce the chances of these really bad fires,” Burke told Hill.

Preterm birth costs about $ 25 billion annually to the national health system, so Burke argued that even a slight reduction in the risk of preterm birth could provide “huge social benefits.”

The average social cost of each preterm birth is about $ 65,000. That is, the social costs associated with smoke exposure in California in 2008 were approximately $ 130 million. He calculated that by 2020, it would be about 2.5 times the exposure and the associated costs would approach $ 325 million.

Burke explained that assessing the cost of open burning is a bit more “everywhere” and that $ 1,000 per acre is one of the most commonly used indicators. He said this would require an investment of approximately $ 1 billion if California needed about 1 million acres to be treated.

With these numbers in mind, Burke explained that preterm birth alone can justify about one-third of the amount California needs to spend to mitigate the risk of wildfires.

“But the spending needed cannot be justified by the effects of preterm birth alone,” he added.