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Summary: Air pollution is known to harm children’s respiratory health, but its specific impacts on infection rates have remained unclear. A new analysis provides evidence of a link between the two in low-income settings, and indicates one industry may play an outsized role in the problem.

Studies have shown air pollution is a major risk factor for respiratory infection — the leading cause of death among children under five — but bad air’s specific impacts on developing bodies have remained somewhat of a mystery.

A Stanford-led study reveals a link between tiny airborne particles and child health in South Asia, a region beset with air pollution and more than 40 percent of global pneumonia cases. The analysis, published in Environmental Pollution, estimates the effect of increased particulate on child pneumonia hospitalizations is about twice as much as previously thought, and indicates a particular industry may play an outsized role in the problem.

The findings could help public health officials and policymakers better target emissions reduction programs to improve child health.

“Everybody wants to protect kids’ health,” said study lead author Allison Sherris, a postdoctoral research fellow in Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences. “Now, we have evidence of a clear health benefit to children from reducing ambient PM2.5 emissions in Dhaka.”

For many of the 21 million residents of Dhaka, Bangladesh — the study’s focus area — air pollution is an all-too-regular part of life, especially in winter, when coal-burning brick kilns around the city operate. Of special concern is PM2.5, airborne particles 2.5 micrometers wide or smaller. The larger of these particles are about one-thirtieth the width of a human hair, small enough to inhale deep into the lungs.

Once inside the lungs, these particles can cause inflammation and impair the body’s ability to fight infection. But particles from different sources can have different shape, size and chemical composition, and it’s not clear what specific components of PM2.5 might be most harmful.

Few studies have evaluated the health effects of PM2.5 in infants and young children, especially in low-income countries where children are more than 60 times as likely to die from air pollution exposure as children in high-income countries, according to the World Bank. Among studies that have, most focused on the indoor environment, where the use of biomass-burning cookstoves has been associated with child respiratory infection.

“Specifying the impact of industry-generated air pollution on child health provides compelling evidence to support interventions to reduce pollution,” said study senior author Stephen Luby, a professor of infectious diseases at Stanford University. “This is often more salient to politicians than the marginal contribution of emissions to global climate change.”

Sherris, Luby and their colleagues analyzed long-term PM2.5 monitoring data alongside community health surveillance of respiratory infections from the Atomic Energy Centre, Dhaka, and the International Centre for Diarrhoeal Disease Research, Bangladesh. They found pneumonia incidence among children under 5 increased by 3.2 percent for every PM2.5 increase of 10 micrograms per cubic meter of air — a standard measure in air pollution analysis.

The mean PM2.5 level in Dhaka was on average over three times higher than the World Health Organization standard. The association between air pollution and child pneumonia suggests that air pollution is a major contributor to the leading cause of child death in Bangladesh and across South Asia.

That difference equates to more than 200,000 additional child pneumonia cases in Bangladesh each year, and nearly two million additional cases across South Asia. The increase is also approximately double similar prior estimates of pneumonia hospitalizations associated with increased PM2.5 and about 10 times more than such estimates for outpatient visits.

The difference from previous findings may reflect the young age of the study population — most children in the study were two or younger — the source composition of particulate matter in Dhaka, and the fact that the study included nearly all community infection cases, rather than just focusing on cases that made it to clinics and hospitals.

Prior studies by researchers at the Atomic Energy Centre, Dhaka found that biomass burning contributed the most to outdoor PM2.5 levels, followed by brick kiln emissions and soil dust. However, on days when brick kilns contributed a heavier than-usual amount of PM2.5 to the mix of bad air, the link between PM2.5 and child pneumonia was stronger.

The findings are among the first evidence that communities and policymakers can point to that suggests a measurable impact of brick kilns on child health. Considering 9 out of 10 people live in areas with air pollution exceeding World Health Organization guidelines, further investigation into whether particles from brick kilns and other sources have different health impacts could inform health and environmental interventions around the world. Luby leads a collaboration among public health experts, industry stakeholders, technology consultants and government agencies to improve the industry. He received funding for related work focused on brick kilns and other industries, funded by the Sustainability Initiative that gave rise to Stanford’s new school focused on climate and sustainability.

“We’re still only looking at a small slice of the potential health outcomes that might be linked to this kind of air pollution, and we still lack perfect measurements of exposure to it,” said Sherris. “The true health burden is likely much greater.

Pollution’s impact on child health — ScienceDaily

Studies have shown air pollution is a major risk factor for respiratory infection – the leading cause of death among children under five – but bad air’s specific impacts on developing bodies have remained somewhat of a mystery.

A Stanford-led study reveals a link between tiny airborne particles and child health in South Asia, a region beset with air pollution and more than 40 percent of global pneumonia cases. The analysis, published in Environmental Pollution, estimates the effect of increased particulate on child pneumonia hospitalizations is about twice as much as previously thought, and indicates a particular industry may play an outsized role in the problem.

The findings could help public health officials and policymakers better target emissions reduction programs to improve child health.

“Everybody wants to protect kids’ health. Now, we have evidence of a clear health benefit to children from reducing ambient PM2.5 emissions in Dhaka.” Allison Sherris, study lead author, postdoctoral research fellow in Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences

For many of the 21 million residents of Dhaka, Bangladesh – the study’s focus area – air pollution is an all-too-regular part of life, especially in winter, when coal-burning brick kilns around the city operate. Of special concern is PM2.5, airborne particles 2.5 micrometers wide or smaller. The larger of these particles are about one-thirtieth the width of a human hair, small enough to inhale deep into the lungs.

Once inside the lungs, these particles can cause inflammation and impair the body’s ability to fight infection. But particles from different sources can have different shape, size and chemical composition, and it’s not clear what specific components of PM2.5 might be most harmful.

Few studies have evaluated the health effects of PM2.5 in infants and young children, especially in low-income countries where children are more than 60 times as likely to die from air pollution exposure as children in high-income countries, according to the World Bank. Among studies that have, most focused on the indoor environment, where the use of biomass-burning cookstoves has been associated with child respiratory infection.

“Specifying the impact of industry-generated air pollution on child health provides compelling evidence to support interventions to reduce pollution,” said study senior author Stephen Luby, a professor of infectious diseases at Stanford University. “This is often more salient to politicians than the marginal contribution of emissions to global climate change.”

Sherris, Luby and their colleagues analyzed long-term PM2.5 monitoring data alongside community health surveillance of respiratory infections from the Atomic Energy Centre, Dhaka, and the International Centre for Diarrhoeal Disease Research, Bangladesh. They found pneumonia incidence among children under 5 increased by 3.2 percent for every PM2.5 increase of 10 micrograms per cubic meter of air – a standard measure in air pollution analysis.

The mean PM2.5 level in Dhaka was on average over three times higher than the World Health Organization standard. The association between air pollution and child pneumonia suggests that air pollution is a major contributor to the leading cause of child death in Bangladesh and across South Asia.

That difference equates to more than 200,000 additional child pneumonia cases in Bangladesh each year, and nearly two million additional cases across South Asia. The increase is also approximately double similar prior estimates of pneumonia hospitalizations associated with increased PM2.5 and about 10 times more than such estimates for outpatient visits.

The difference from previous findings may reflect the young age of the study population – most children in the study were two or younger – the source composition of particulate matter in Dhaka, and the fact that the study included nearly all community infection cases, rather than just focusing on cases that made it to clinics and hospitals.

Prior studies by researchers at the Atomic Energy Centre, Dhaka found that biomass burning contributed the most to outdoor PM2.5 levels, followed by brick kiln emissions and soil dust. However, on days when brick kilns contributed a heavier than-usual amount of PM2.5 to the mix of bad air, the link between PM2.5 and child pneumonia was stronger.

The findings are among the first evidence that communities and policymakers can point to that suggests a measurable impact of brick kilns on child health. Considering 9 out of 10 people live in areas with air pollution exceeding World Health Organization guidelines, further investigation into whether particles from brick kilns and other sources have different health impacts could inform health and environmental interventions around the world. Luby leads a collaboration among public health experts, industry stakeholders, technology consultants and government agencies to improve the industry. He received funding for related work focused on brick kilns and other industries, funded by the Sustainability Initiative that gave rise to Stanford’s new school focused on climate and sustainability.

“We’re still only looking at a small slice of the potential health outcomes that might be linked to this kind of air pollution, and we still lack perfect measurements of exposure to it,” said Sherris. “The true health burden is likely much greater.

Study reveals a link between air pollution and child health

Summary: Researchers found increased concentrations of air pollutants downwind from oil and gas wells in California, likely affecting millions of Californians who live near them.

In a 14-year analysis of air quality across California, Stanford researchers observed higher levels of air pollutants within 2.5 miles of oil and gas wells, likely worsening negative health outcomes for nearby residents.

The scientists analyzed local air quality measurements in combination with atmospheric data and found that oil and gas wells are emitting toxic particulate matter (PM2.5), carbon monoxide, nitrous oxide, ozone and volatile organic compounds (VOCs). The findings, which appear in the journal Science of the Total Environment, will help researchers determine how proximity to oil and gas wells may increase the risk of adverse health outcomes, including preterm birth, asthma and heart disease.

“In California, Black and Latinx communities face some of the highest pollution from oil and gas wells. If we care about environmental justice and making sure every kid has a chance to be healthy, we should care about this,” said lead author David Gonzalez, who conducted research for the study while a PhD student in Stanford’s Emmett Interdisciplinary Program in Environment and Resources (E-IPER). “What’s novel about our study is that we’ve done this at a population, state-wide scale using the same methods as public health studies.”

The findings align with other smaller-scale studies that have measured emissions from a handful of wells. At least two million Californians live within one mile of an active oil or gas well.

“It’s really hard to show air quality impacts of an activity like oil and gas production at a population scale, but that’s the scale we need to be able to infer health impacts,” said senior study author Marshall Burke, an associate professor of Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “While it’s not necessarily surprising that drilling and operating oil and gas wells emit air pollutants, knowing the magnitude of the effect improves our broader understanding of who is exposed to what and how to intervene to improve health outcomes.”

A global killer

The research reveals that when a new well is being drilled or reaches 100 barrels of production per day, the deadly particle pollution known as PM2.5increases two micrograms per cubic meter about a mile away from the site. A recent study published in Science Advances found that long-term exposure to one additional microgram per meter cubed of PM2.5 increases the risk of death from COVID-19 by 11 percent.

“We started in 2006 because that’s when local agencies started reporting PM2.5 concentrations,” said Gonzalez, who is now a postdoctoral researcher at the University of California, Berkeley. “We’re very concerned about particulate matter because it’s a leading global killer.”

The team evaluated about 38,000 wells that were being drilled and 90,000 wells in production between 2006 and 2019. They developed an econometric model incorporating over a million daily observations from 314 air monitors in combination with global wind direction information from the National Oceanic and Atmospheric Administration (NOAA) to determine if the pollutants were coming from the wells.

Other factors that could be contributing to elevated emissions were controlled for — such as wildfire smoke or industrial activities — and monitors located far from drilling sites were used to identify those factors unrelated to wells. They also analyzed locations with air quality data from both before and after a well was drilled.

“Sometimes the wind is blowing from the well, sometimes it’s not, and we found significantly higher pollution on days when the wind is blowing from the wells,” Gonzalez said. “As a control, we assumed wells that are downwind of the air monitor shouldn’t contribute any pollution — and that is indeed what we saw.”

The research also reveals that ozone — a powerful oxidant that can cause wheezing, shortness of breath and aggravated lung disease — was present up to 2.5 miles from wells. Children are at the greatest risk from exposure to ozone because their lungs are still developing, according to the Environmental Protection Agency (EPA).

Chronic exposure

The new study contributes to a growing body of evidence about the dangers of living near oil and gas wells that may help guide ongoing policymaking around residential setbacks from drilling sites. For example, LA County recently voted to phase out oil and gas drilling, citing issues of climate change, environmental impacts and equity, and other California cities are in discussion about neighborhood drilling regulations.

“Many of California’s oil fields have been operating for decades. People that live near them have been chronically exposed to higher levels of pollution — and a lot of these wells are located in neighborhoods that are already burdened by pollution,” Gonzalez said. “Our study adds to the evidence that public health policies are needed to reduce residents’ exposure to air pollution from wells.”

Although data for the research is from California, the co-authors say the findings are likely applicable to other regions with oil and gas operations.

“We’ve had earlier papers suggesting that proximity to oil and gas production worsens health outcomes, and the likely channel was through air pollutants, but we previously didn’t have a good way to demonstrate that was the case,” Burke said. “This new work is helping confirm that air pollution was the missing link between this type of energy production and the bad outcome that we cared about.

Living near oil and gas wells increases air pollution exposure — ScienceDaily