california oil and gas

Californians living within miles of oil and gas wells have toxic air

"For many years, communities have been complaining about how oil drilling in their neighborhoods is harmful. Now we have numbers to back that up."

People living within 2.5 miles of oil and gas wells in California are exposed to levels of air pollutants linked to asthma, cancer, cardiovascular diseases, preterm birth, and other long-term health defects, according to a new study published in September in the journal Science of The Total Environment.


Although it is well-established that oil and gas wells can contribute to air pollution and jeopardize the health of surrounding residents, this study is the first to pinpoint to what extent each common air pollutant can be attributed to fossil fuel production using large-scale state-wide data.

The study analyzed roughly one million daily entries from more than 300 air monitors across California from 2006 to 2019. After pairing air monitor data with upstream oil and gas production activities and leveraging wind direction to discern the pollution from the wells, the scientists observed higher concentrations of particulate matter (PM2.5), carbon monoxide, nitrous oxide, and ozone within two miles of the pre-production wells (wells that have not been completed for production). For active wells, the study found spiked PM2.5, nitrous oxide, and volatile organic compounds emissions within 0.6 miles of the production sites, and higher ozone concentrations between 0.6 and 1.2 miles from the wells.

The study adds to mounting evidence of oil and gas production's harm on California's underrepresented and poorly-resourced communities. At the southern end of the state's Central Valley, Kern County—which has roughly 78% of active wells in California and produces more than 70% of the oil and gas in the state—has heavily polluted air that "may put your health at risk," according to the American Lung Association. A 2015-17 community health report published by the county's health department revealed that lung cancer was the leading cause of death for the county's residents, more than half of whom are people of color. Meanwhile, the county—with 19% of people living below the poverty line (1.5 times the national rate)—also experienced higher infant mortality and heart disease death rates than the state average. Between 2015 to 2017, more Kern residents under age 5 and over age 65 went to the emergency room due to asthma than in the state as a whole.

"For many years, communities have been complaining about how oil drilling in their neighborhoods is harmful," David Gonzalez, an environmental scientist at University of California, Berkeley, and lead author of the paper, told EHN. "Now we have numbers to back that up."

Air pollution and health 

There are approximately one million active oil and natural gas wells on U.S. soil, penetrating the Earth from mountains, deserts, and, in many cases, people's backyards. About 12.8 million barrels of oil are sucked out of the country's ground every day.

Across the country, more than 17 million people—including 2.1 million Californians—live within a mile of at least one active drilling well, which is linked to a plethora of deleterious health outcomes—cardiovascular diseases, depression symptoms and sleep disorders, and detrimental birth outcomes. PM2.5—a deadly pollutant particle 30 times smaller than human hair—invades deep inside our lungs and into our blood. Another pollutant studied in this paper, ozone, can stiffen up our airway muscles and, as a result, trap air at the end-branches of our lungs and increase asthma risk. The molecule poses the greatest threat to children, whose respiratory systems are still developing.

Fracking investigation 

One limit of the new study is that it only looked into how common air pollutants were attributed to oil and gas productions. "We're just scratching the surface here," said Gonzalez, adding that there could be plenty of other harmful chemicals and environmental impacts—such as noise and greenhouse gas emissions—not considered in this study.

In 2021, EHN's own 'Fractured' investigation—which examined urine, air, and water samples from households in southwestern Pennsylvania near fracking sites—found chemicals including benzene and butylcyclohexane in drinking water and air samples. The analysis also revealed that breakdown chemical molecules such as ethylbenzene, styrene, and toluene in children residing near fracking wells at levels up to 91 times as high as the average American.

The health effects of drilling wells go beyond adjacent communities. EHN's investigation discovered people who were exposed to harmful compounds five miles away from fracking wells.

Joan Casey, an environmental epidemiology professor at Columbia University who was not involved in the study, told EHN that this new paper "fills a big gap" in understanding how oil and gas developments can harm people's health.

As this study helps "illuminate the black box," Casey said, "the time has come for us to step back and reduce the use of fossil fuels."

Banner photo: Global Climate Action Summit in California in 2018. (Credit: Peg Hunter/flickr)

A gleaming glass skyscraper with the word Allianz on the top.

Insurers warn climate change could unravel financial markets and endanger capitalism

A top executive at Allianz says the climate crisis is pushing insurance and broader financial systems toward collapse as rising temperatures and extreme weather make entire regions uninsurable.

Damian Carrington reports for The Guardian.

Keep reading...Show less
Senator Whitehouse & climate change

Senator Whitehouse puts climate change on budget committee’s agenda

For more than a decade, Senator Sheldon Whitehouse gave daily warnings about the mounting threat of climate change. Now he has a powerful new perch.
Hands of a man sitting at a desk with a laptop filling out a paper form with a pen.

Lawyers turn to pro bono work to drive climate solutions beyond the courtroom

A growing virtual bootcamp trains legal professionals to support climate initiatives through everything from contracts to corporate advising.

Claire Elise Thompson reports for Grist.

Keep reading...Show less
Wind turbines in the distance with a yellow field in the foreground and a blue sky in the background.

Trump tariffs may raise U.S. wind energy prices and stall project growth

Tariffs proposed by President Trump could raise the cost of building wind power projects in the U.S., threatening the already fragile momentum of the renewable energy sector.

Stanley Reed reports for The New York Times.

Keep reading...Show less
A sign in front of a Max-Planck Institut building with bushes nearby.
Credit: ginton/BigStock Photo ID: 71957491

Trump’s anti-science agenda is pushing American researchers overseas

A growing number of U.S. scientists are fleeing restrictive policies under Trump and finding support in Europe, where institutions are rolling out the red carpet for displaced talent.

Fred Schwaller reports for DW.

Keep reading...Show less
hands holding food scraps above a green food composting bucket.
Credit: digitalista/BigStock Photo ID: 468529199

New approach to composting in Massachusetts relies on hands-on help, not just rules

In Massachusetts, a state composting mandate for businesses gets a major assist from a down-to-earth consultant who helps restaurants rethink what they throw away.

Somini Sengupta reports for The New York Times.

Keep reading...Show less
An African man smiles as he stands in front of rural solar infrastructure and water tanks in a golden field.
Credit: Hamish John Appleby / IWMI Flickr Photos

How solar is helping African farmers beat drought and diesel

Solar-powered irrigation is quietly transforming small farms across Africa, helping farmers boost yields, cut costs, and ditch dirty diesel.

Aimable Twahirwa reports for Mongabay.

Keep reading...Show less
A pig on a farm pokes its snout through a rusted cage with more pigs in background.
Credit: Tzido/Big Stock Photo ID: 4126064

Rural families use innovative DNA tool to track pig farm pollution

Communities living near factory farms are using a new scientific tool to track pig feces in their homes — and fight back.

Hana Mensendiek reports for U.S. Right To Know.

Keep reading...Show less
From our Newsroom
Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

People  sitting in an outdoors table working on a big sign.

Op-ed: Why funding for the environmental justice movement must be anti-racist

We must prioritize minority-serving institutions, BIPOC-led organizations and researchers to lead environmental justice efforts.

joe biden

Biden finalizes long-awaited hydrogen tax credits ahead of Trump presidency

Responses to the new rules have been mixed, and environmental advocates worry that Trump could undermine them.

Op-ed: Toxic prisons teach us that environmental justice needs abolition

Op-ed: Toxic prisons teach us that environmental justice needs abolition

Prisons, jails and detention centers are placed in locations where environmental hazards such as toxic landfills, floods and extreme heat are the norm.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.