Formaldehyde Causes More Cancer Than Any Other Toxic Air Pollutant. Little Is Being Done to Curb the Risk

In a world flush with hazardous air pollutants, there is one that

causes far more cancer than any other, one that is so widespread

that nobody in the United States is safe from it.

It is a chemical so pervasive that a new analysis by ProPublica found

it exposes everyone to elevated risks of developing cancer no matter

where they live. And perhaps most worrisome, it often poses the

greatest risk in the one place people feel safest: inside their homes.

As the backbone of American commerce, formaldehyde is a

workhorse in major sectors of the economy, preserving bodies in

funeral homes, binding particleboards in furniture and serving as a

building block in plastic. The risk isn’t just to the workers using it;

formaldehyde threatens everyone as it pollutes the air we all breathe

and leaks from products long after they enter our homes. It is

virtually everywhere.

Federal regulators have known for more than four decades that

formaldehyde is toxic, but their attempts to limit the chemical have

been repeatedly thwarted by the many companies that rely on it.

This year, the Biden administration finally appeared to make some

progress. The Environmental Protection Agency is expected to take

a step later this month toward creating new rules that could restrict

formaldehyde. But the agency responsible for protecting the public from the harms

of chemicals has significantly underestimated the dangers posed by

formaldehyde, a ProPublica investigation has found.

The EPA is moving ahead after setting aside some of its own

scientists’ conclusions about how likely the chemical is to cause

myeloid leukemia, a potentially fatal blood cancer that strikes an

estimated 29,000 people in the U.S. each year. The result is that

even the EPA’s alarming estimates of cancer risk vastly

underestimate — by as much as fourfold — the chances of

formaldehyde causing cancer.

The agency said it made the decision because its estimate for

myeloid leukemia was “too uncertain” to include. The EPA noted

that the National Academies of Sciences, Engineering and Medicine,

which the agency paid to review its report, agreed with its decision

not to include myeloid leukemia in its cancer risk. But four former

government scientists with experience doing statistical analyses of

health harms told ProPublica that the myeloid leukemia risk

calculation was sound. One said the risk was even greater than the

agency’s estimate.

Jennifer Jinot, one of the EPA scientists who spent years calculating

the leukemia risk, said there is always uncertainty around estimates

of the health effects of chemicals. The real problem, she said, was

cowardice.

“In the end, they chickened out,

” said Jinot, who retired in 2017

after 26 years working at the EPA. “It was kind of heartbreaking.”

The EPA has also retreated from some of its own findings on the

other health effects of formaldehyde, which include asthma in both

children and adults; other respiratory ailments, including reduced

lung function; and reproductive harms, such as miscarriages and

fertility problems. In a draft report expected to be finalized this

month, the agency identified many instances in which formaldehyde

posed a health threat to the public but questioned whether most of

those rose to a level the agency needed to address. In response to

questions from ProPublica, the EPA wrote in an email that the

report was not final and that the agency was in the process of

updating it.

Still, if the past is any guide, even the limited efforts of President

Joe Biden’s administration are all but guaranteed to hit a dead end

after Donald Trump is inaugurated. And one of the longest-running

attempts to restrict a dangerous chemical in American history

would be set back yet again.

ProPublica reporters have spent months investigating

formaldehyde, its sweeping dangers and the government’s long,

frustrating battle to curb how much of it we breathe.

They have analyzed federal air pollution data from each of the

nation’s 5.8 million populated census blocks and done their own

testing in homes, cars and neighborhood businesses. They have

interviewed more than 50 experts and pored through thousands of

pages of scientific studies and EPA records. They’ve also reviewed

the actions of the previous Trump administration and what’s been

disclosed about the next.

The conclusion: The public health risks from formaldehyde are

greater and more prevalent than widely understood — and any hope

of fully addressing them may well be doomed, at least for the

foreseeable future.

Since its inception, the EPA has been outgunned by the profitable

chemical industry, whose experts create relatively rosy narratives

about their products. That battle intensified over the last four years

as the EPA tried to evaluate the scope of the public health threat

posed by formaldehyde.

Regulatory rules put the onus on the government to prove a

chemical is harmful rather than on industry to prove its products

are safe. Regardless of who is in the White House, the EPA has staff

members with deep ties to chemical companies. During some

administrations, it is run by industry insiders, who often cycle

between jobs in the private sector and the government.

Trump has already vowed to roll back regulations he views as anti-

business — an approach that promises to upend the work of

government far beyond formaldehyde protections. Still, this one

chemical makes clear the potential human toll of crafting rules to

serve commerce rather than public health. And Trump’s last term as

president shows how quickly and completely the efforts now

underway might be stopped.

At the EPA, he appointed a key figure from the chemical industry

who had previously defended formaldehyde. The agency then

quietly shelved a report on the chemical’s toxicity. It refused to

enforce limits on formaldehyde released from wood products until a

judge forced its hand. And it was under Trump that the agency first

decided not to include its estimate of the risk of developing myeloid

leukemia in formaldehyde’s overall cancer risk calculation,

weakening the agency’s ability to protect people from the disease.

The latest efforts to address formaldehyde pollution are likely to

meet a similar fate, according to William Boyd, a professor at UCLA

School of Law who specializes in environmental governance. Boyd

has described formaldehyde as a sort of poster child for the EPA’s

inability to regulate chemicals. Because formaldehyde is key to so

many lucrative industrial processes, companies that make and use it

have spent lavishly on questioning and delaying government efforts

to rein it in.

“The Biden administration was finally bringing some closure to that

process, ” said Boyd. “But we have every reason to suspect that those

efforts will now be revised. And it will likely take years for the EPA

to do anything on this.”

Invisible Threat

Perhaps best known for preserving dead frogs in high school biology

labs, formaldehyde is as ubiquitous in industry as salt is in cooking.

Between 1 billion and 5 billion pounds are manufactured in the U.S.

each year, according to EPA data from 2019.

Outdoor air is often suffused with formaldehyde gas from cars,

smoke, factories, and oil and gas extraction, sometimes at worrying

levels that are predicted to worsen with climate change. Much of the

formaldehyde outdoors is also spontaneously formed from other

pollutants.

Invisible to the eye, the gas increases the chances of getting cancer

— severely in some parts of the country.

This year, the EPA released its most sophisticated estimate of the

chance of developing cancer as a result of exposure to chemicals in

outdoor air in every populated census block across the United

States. The agency’s sprawling assessment shows that, among

scores of individual air pollutants, formaldehyde poses the greatest

cancer risk — by far.

But ProPublica’s analysis of that same data showed something far

more concerning: It isn’t just that formaldehyde poses the greatest

risk. It’s that its risk far exceeds the agency’s own goals, sometimes

by significant amounts.

ProPublica found that, in every census block, the risk of getting

cancer from exposure to formaldehyde in outdoor air over a lifetime

is higher than the limit of one incidence of cancer in a million

people, the agency’s goal for air pollutants. That risk level means

that if a million people in an area are continuously exposed to

formaldehyde over 70 years, the chemical would cause at most one

case of cancer, on top of those from other risks people already face.

According to ProPublica’s analysis of the EPA’s 2020 AirToxScreen

data, some 320 million people live in areas of the U.S. where the

lifetime cancer risk from outdoor exposure to formaldehyde is 10

times higher than the agency’s ideal.

(ProPublica is releasing a lookup tool that allows anyone in the

country to understand their outdoor risk from formaldehyde.)

In the Los Angeles/San Bernardino, California, area alone, some 7.2

million people are exposed to formaldehyde at a cancer risk level

more than 20 times higher than the EPA’s goal. In an industrial

area east of downtown Los Angeles that is home to several

warehouses, the lifetime cancer risk from air pollution is 80 times

higher, most of it stemming from formaldehyde.

Even those alarming figures underestimate the true danger. As the

EPA admits, its cancer risk calculation fails to reflect the chances of

developing myeloid leukemia. If it had used its own scientists’

calculation — “the best estimate currently available,

” according to the agency’s August report — the threat of the chemical would be

shown to be far more severe. Instead of causing 20 cancer cases for

every million people in the U.S., formaldehyde would be shown to

cause approximately 77.

Using the higher figure to set regulations of the chemical could

eventually help prevent thousands of cases of myeloid leukemia,

according to ProPublica’s analysis.

As Mary Faltas knows, the diagnosis can upend a life.

Faltas, 60, is still sorting through the aftermath of having myeloid

leukemia, which she developed in 2019. “It’s like having a storm

come through,

” she said recently. “It’s gone, but now you’re left with

everything else to deal with.”

It wasn’t always clear she’d survive. There are two types of myeloid

leukemia. Faltas had the more deadly acute form and spent a year

and a half undergoing chemotherapy, fighting life-threatening

infections and receiving a bone marrow transplant. Too sick to

work, she lost her job as a dental assistant. She and her husband

were forced to sell their house in Apopka, Florida, and downsize to a

small condo — a move that took place when she was too weak to

pack a box.

It’s almost always impossible to pinpoint a single cause for

someone’s cancer. But Faltas has spent her entire life in places

where the EPA’s data shows there is a cancer risk 30 times the level

the agency says it strives to meet. And in that way, she’s typical.

Nationwide, that’s the average lifetime cancer risk from air

pollution; formaldehyde accounts for most of it. Factor in the EPA’s

myeloid leukemia calculation, and Faltas has lived in places where

cancer risk from formaldehyde alone is 50 to 70 times the agency’s

goal.

Layered on top of the outdoor risk we all face is the much more

considerable threat indoors — posed by formaldehyde in furniture,

flooring, printer ink and dozens of other products. The typical home

has a formaldehyde level more than three times higher than the one

the EPA says would protect people against respiratory symptoms.

The agency said it came up with its recommended level to protect

sensitive subgroups and that the potential for health effects just

above it are “unknown.”

The EPA’s own calculations show that formaldehyde exposure in

those homes would cause as many as 255 cancer cases in every

million people exposed over their lifetimes — and that doesn’t

reflect the risk of myeloid leukemia. The agency also said “there

may not be a feasible way currently to reduce the average indoor

level of formaldehyde to a point where there is no or almost no

potential risk.”

ProPublica will delve more into indoor risks, and how to guard

against them, in the coming days.

The Long Road to Nowhere

The fruitless attempts to limit public exposure to formaldehyde

stretch back to the early ’80s, soon after the chemical was shown to

cause cancer in rats.

The EPA planned to take swift action to reduce the risks from

formaldehyde, but an appointee of President Ronald Reagan named

John Todhunter stopped the effort. He argued that formaldehyde

didn’t pose a significant risk to people. A House investigation later

revealed he had met with chemical industry representatives,

including a lobbyist from the Formaldehyde Institute, just before

making his decision. Todhunter denied being influenced but

resigned under pressure.

In 1991, under President George H.W. Bush, the EPA finally deemed

formaldehyde a probable human carcinogen and calculated the

likelihood of it causing an extremely rare cancer that affects a part

of the throat called the nasopharynx. But it quickly became clear

that more protection was needed.

A 2003 study showed that factory workers exposed to high levels of

formaldehyde were 3 1/2 times more likely to develop myeloid

leukemia than workers exposed to low levels of the chemical.

“Having human data showing an effect like that ... it’s a rare thing,

said Jinot, the former EPA statistician and toxicologist. “You want

to seize that opportunity.”

She and colleagues at the agency crunched numbers, immersed

themselves in the medical literature and consulted with other

scientists to conclude that formaldehyde was a known carcinogen

and caused myeloid leukemia, among other cancers.

But in 2004, their work hit a roadblock. Sen. James Inhofe, R-Okla.,

persuaded the EPA to delay the update of its formaldehyde report

until the National Cancer Institute released the results of a study

that was underway. The harms, meanwhile, continued to mount. In 2006, people who

lost their homes in Hurricane Katrina and were housed in

government trailers began to report feeling sick. The symptoms,

which included breathing difficulties, eye irritation and nosebleeds,

were traced to high levels of formaldehyde.

In 2009, under the Obama administration, the EPA was once again

poised to release its report on the toxicity of formaldehyde. By then,

the National Cancer Institute’s study had been published, making

the link between formaldehyde and myeloid leukemia even clearer.

This time, another U.S. senator intervened. David Vitter, R-La., who

had received donations from chemical companies and a

formaldehyde lobbyist, held up the confirmation of an EPA

nominee. He agreed to approve the nomination in exchange for an

additional review of the formaldehyde report by a panel of the

National Academies of Sciences, Engineering and Medicine.

The outside review found “problems with clarity and transparency

of the methods” used in the EPA report and recommended that, in

its next version, the EPA employ “vigorous editing” and explain its

arguments more clearly.

But the EPA would not issue that next version for more than a

decade. After the outside review, the chemical industry seized on its

findings as evidence of fundamental problems at the agency. For

years afterward, the EPA’s release of chemical assessments — and

its work on the formaldehyde assessment — slowed. “They became

completely cowardly,

” Jinot said. “They were shell-shocked and

retreated.”

As the EPA went about revising its report, it fell behind others

around the world in recognizing that formaldehyde causes cancer.

The World Health Organization’s arm that researches cancer had

already concluded in 2006 that the chemical is a carcinogen. Five

years later, scientists with the Department of Health and Human

Services found that formaldehyde causes cancer, citing studies

linking it to myeloid leukemia.

Between 2011 and 2017, the Foundation for Chemistry Research

and Initiatives, which had been created by an industry trade group,

funded 20 studies of the chemical. The research presented

formaldehyde as relatively innocuous. The industry trade group still

disputes the mainstream science, insisting that “the weight of

scientific evidence” shows that formaldehyde does not cause

myeloid leukemia.

The trade group’s panel on formaldehyde also complained that

regulation would be devastating for business. The argument was

undercut by one of the few limits the EPA did manage to put in

place.

In 2016, the EPA issued a rule limiting the release of formaldehyde

from certain wood products sold in the U.S. Under Trump, the

agency did not implement the rule until a court ordered it to in

2018.

But once the regulation was in effect, many companies complied

with it. Necessity bred invention, and furniture and wood products

makers found glues and binders with no added formaldehyde.

Still, under Trump, the EPA refused to move forward with other

efforts that had been underway to tighten regulations of

formaldehyde. When he assumed office, the agency was yet again

preparing to publish the toxicity report that Jinot had been working

on.

One of the new Trump appointments to the EPA was David Dunlap,

a chemical engineer who, as the director of environmental

regulatory affairs for Koch Industries, had tried to persuade the

EPA that formaldehyde doesn’t cause leukemia. Koch’s subsidiary,

Georgia-Pacific, made formaldehyde and many products that emit

it. (Georgia-Pacific has since sold its chemicals business to Bakelite

Synthetics.) At the EPA, Dunlap had authority over the division

where Jinot and other scientists were working on the toxicity report.

Ethics rules require federal employees not to participate in matters

affecting former clients for two years. Dunlap complied with the

law, recusing himself in 2018 from work on formaldehyde, but only

after taking part in internal agency discussions about its health

effects. He signed his recusal paperwork the same day the EPA

killed the toxicity report. Dunlap did not respond to requests for

comment.

Imperfect Progress, Inevitable Disruption

This August, the Biden EPA finally managed to carry that report

across the finish line, getting it reviewed by other agencies and the

White House. For the first time, it also set a threshold to protect

people from breathing difficulties caused by formaldehyde, such as

increased asthma symptoms and reduced lung function.

In a draft of another key report on formaldehyde released this year,

the EPA found that levels of the chemical were high enough to

potentially trigger health problems in dozens of scenarios, including

workers using lawn and garden products and consumers who might

inhale the chemical as it wafts from cleaners, foam seating and

flooring. But the agency is required to address risks only if they are

deemed “unreasonable.” For many of those risks, the EPA said it

wasn’t certain they were unreasonable.

The EPA made the decision after employing a variety of unusual

scientific strategies. One involved outdoor air. The EPA first

estimated the amount of formaldehyde in the air near some of the

country’s biggest polluters. To determine whether those amounts

posed an unreasonable risk of harm, the agency compared them to a

specific benchmark — the highest concentration of formaldehyde

measured by government monitors in outdoor air between 2015 and

2020. EPA records show that peak level was recorded in 2018 in

Fontana, California, about 50 miles east of Los Angeles. The EPA

concluded the levels near polluting factories would not be

unreasonable if they were below this record high, even though local

scientists had noted that the Fontana reading didn’t meet their

quality control standards, according to documents obtained by

ProPublica. Local air quality officials said they didn’t know what

caused the temporary spike in the level of formaldehyde near the

Fontana monitor.

The fact that an air monitor in Fontana once registered a fluke

reading that dwarfs the level of formaldehyde in the air near her

home is of little comfort to Rocky Rissler.

A retired teacher, Rissler shares her home in Weld County,

Colorado, with her husband, Rick, two horses, one dog and 12

highland cows; she calls it the “Ain’t Right Ranch” — a name that

feels increasingly fitting as the number of oil and gas facilities near

her home has ballooned in recent years.

The rural area is one of hundreds around the country — many of

them in Colorado, New Mexico, North Dakota and West Virginia —

where the formaldehyde risk is elevated because of oil and gas

production. Gusts of nausea-inducing pollution have become so

frequent that Rissler now carries a peppermint spray with her at all

times to ease the discomfort. She has frequent headaches, and her

asthma has worsened to the point where she’s been hospitalized

three times in recent years. Rissler, who is 60 but says she feels “closer to 99,

” has also been diagnosed with chronic bronchitis and chronic obstructive

pulmonary disease, or COPD — conditions that have been linked to

formaldehyde exposure. Just walking up the slight hill from her

horse barn to her front door can leave her winded.

“It feels like a gorilla is sitting on my chest,

” she said. And while she

used to jog in her youth,

“these days, I’m only running if there’s a

bear chasing me.”

Under Biden, EPA scientists have been sharply divided over how to

gauge all the dangers of formaldehyde. Some employees throughout

the agency have been working to strengthen the final health

assessment expected later this month. But they are fighting against

immense outside pressure.

During the past four years, no fewer than 75 trade groups have

pushed back against the EPA’s findings. Among them are the

Fertilizer Institute, the Golf Course Superintendents Association of

America, the Toy Association, the National Chicken Council, the

Asphalt Roofing Manufacturers Association, the Independent

Lubricant Manufacturers Association, the RV Industry Association,

the Halogenated Solvents Industry Alliance and the American

Chemistry Council, which represents more than 190 companies and

led the charge. Meanwhile, scientists with ties to the industry are

pushing the EPA to abandon its own toxicity calculations and use

theirs instead — a move that could seriously weaken future limits on

the chemical.

“I’ve seen the industry engage on lots of different risk assessments,

said Tracey Woodruff, a professor and director of the Program on

Reproductive Health and the Environment at the University of

California, San Francisco. “This one feels next level.”

An EPA spokesperson wrote in an email that the agency’s draft risk

evaluation of formaldehyde was “based purely on the best available

science.”

The industry’s fortunes have now shifted with Trump’s election.

Despite campaign assurances that he wants “really clean water,

really clean air,

” Trump is expected to eviscerate dozens of environmental protections, including many that limit pollution in

water and air. He will have support from a Republican Congress,

where some have long wanted to rewrite environmental laws,

including the one regulating chemicals.

Trump has already laid out a plan to require federal agencies to cut

10 rules for every one they introduce, a far more aggressive

approach than he took during his last time in the White House,

when he rolled back more than 100 environmental rules. And his

transition team has floated the idea of relocating the EPA

headquarters, a move that would surely cause massive reductions in

staff.

According to regulatory experts consulted by ProPublica, the

incoming administration could directly interfere with the ongoing

review of formaldehyde in several ways. The EPA could simply

change its reports on the chemical’s health effects.

“They can just say they’re reopening the risk assessment and take

another look at it. There may be some legal hurdles to overcome,

but they can certainly try,

” said Robert Sussman, an attorney who represents environmental groups and served in the EPA under

Presidents Bill Clinton and Barack Obama.

Project 2025, the conservative playbook organized by the Heritage

Foundation, calls for the EPA’s structure and mission to be “greatly

circumscribed.” Its chapter on the agency specifically recommends

the elimination of the division that evaluated the toxicity of

formaldehyde and hundreds of other chemicals over the past three

decades. Project 2025 also aims to take away funding for research

on the health effects of toxic chemicals and open the EPA to

industry-funded science. Trump distanced himself from Project 2025, saying,

“I don’t know what the hell it is.” But after the election, some of his surrogates

have openly embraced the document, and Trump picked an

architect of the conservative plan to fill a key cabinet post.

Last month, Trump announced he had chosen former U.S. Rep. Lee

Zeldin of New York to head the EPA. Zeldin could not be reached for

comment, and the Trump transition team did not respond to

questions about formaldehyde. In his announcement, Trump said

Zeldin would deliver deregulatory decisions “to unleash the power

of American businesses.”

“The election of Trump is a dream for people who want to

deregulate all chemicals,

” said Woodruff, the University of California, San Francisco, professor. “We are going to continue to

see people get sick and die from this chemical.”