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Blake Darnell on Jan. 17, 2023, at Sunset Park in Lakewood. (Olivia Sun, The Colorado Sun via Report for America)

LAKEWOOD — Blake Darnell and his father, Gordon, gingerly make their way across a layer of sidewalk ice to an overlook, where they peer down at a snow-covered set of bike jumps where Blake spent his teenage years perfecting his moves. 

At age 32, Blake has to limp to the spot. 

Gordon Darnell had thought sending his youngest son to Lakewood High School on a bike, devouring fresh air on the heart-pumping jumps at Sunset Park, was a healthy way for Blake to stay out of trouble. Gordon worked in sporting goods and landed Blake a series of tricked-out Specialized and Diamondback rides that the boy wore out. 

As he talks at the park’s edge, Gordon glances a few hundred yards to the west, where the distinctive roof of Terumo Blood and Cell Technologies slashes across the mountain view. 

The sprawling Terumo campus makes life-saving equipment for blood and cell collection and processing. It’s also been emitting highly toxic ethylene oxide, or EtO, into the surrounding Lakewood neighborhoods for decades, after the chemical sterilizes the gear in the last manufacturing step. The lawsuits are the culmination of years of neighbors’ fears about chemical emissions, and whether state and federal regulators have done enough to protect Lakewood residents. At the very least, neighbors and lawmakers want to know more about what’s coming out of the factory.

The Darnells had no idea Terumo loomed upwind of the bike park until they read the news in 2019 that the U.S. Environmental Protection Agency said the factory’s EtO emissions posed the risk of 600 extra cases of cancer for every 1 million residents who might have high, extended exposure. 

Hearing about Terumo was “like a lightbulb going off,” Gordon Darnell said.

Blake Darnell lost his left leg to acute lymphoblastic leukemia at age 23.  

Treatments permanently damaged his remaining bones and decimated his immune system. Transplanted cord stem cells led to graft versus host disease, which dries up blood flow to joints. He may yet lose his right knee and wrists and shoulders to the creeping necrosis. 

From age 19 to age 24, Blake spent every night in the hospital. He can’t drive a car, in part because he’s been on opioids for pain for 10 straight years. While his friends were graduating, going to college, getting jobs, getting married, Blake says, his life went backward. 

Maybe Blake tipping his front tire down into the park’s bottomland every day was what had first put his life in danger. 

After enduring three home foreclosures from medical bills, double work shifts to pay for $3,000 monthly prescription bills, and countless visits to the ER where they greeted Blake by name, the Darnells want more answers.

What part, if any, Terumo and EtO played in the spirit-crushing illnesses of Blake Darnell and many more Colorado residents will play out in a series of court cases this year. The Darnells and other plaintiffs are suing Terumo for alleged damages, part of a series of cases against a handful of companies using ethylene oxide that make up the nation’s latest and most expensive collection of toxic tort law, targeting various classes of chemicals. 

Ethylene oxide is “insidious,” said Darnell’s attorney, Kurt Zaner, of Zaner Harden Law in Denver. “Blake’s life has been frozen in time.”

Terumo officials say that all along, through years of operations in Lakewood, they have never emitted more than a fraction of the ethylene oxide waste that the EPA allows them under air permits.

But just because Terumo says its emissions were always below government-permitted levels does not give them or any other company “a free pass to injure people by sending out dangerous toxins that cause cancer,” Zaner said.

The percentage of Americans who will develop cancer at some point in their lives.

In September, a Chicago-area jury awarded $363 million to plaintiffs suing over emissions from a medical equipment sterilization plant using ethylene oxide, the first major judgment in the growing body of challenges to the sterilization chemical. Faced with hundreds more suits, Sterigenics in January agreed to pay out $408 million to all the plaintiffs in the Illinois cases.

The courts have consolidated cases from 12 plaintiffs for a July trial in Jefferson County, scheduled over four weeks. A second wave of consolidated cases will follow. 

Some of Terumo’s neighbors are torn between loyalty to what they call “a good company” and the fears raised by the EPA highlighting the plant’s chemical releases. 

Diane Duffey works at Terumo and is also president of the Daniels Welchester Neighborhood Association, part of four generations of family members living three blocks away. Terumo included local leaders on tours in 2018, but not lately, Duffey said. 

Terumo “didn’t invite the heads of the four neighborhoods in because two of the four have cancer,” she said. Duffey is not attributing those cases to ethylene oxide emissions. But she is also not completely reassured by Terumo pointing out that the EPA’s risk calculations are based on a nonexistent scenario of someone living 70 years around the clock in the presence of EtO.

Companies like Terumo, Monsanto with glyphosate, or DuPont and 3M with PFAS “forever chemicals,” endanger neighbors without ever warning them, Zaner said. “It’s great to have a jury system to be a great equalizer, and let members of the community decide,” he said. 

Terumo: Risk is not the same as proof

Cancer rarely arrives with a return address. 

Forty percent of Americans will develop cancer at some point in their lives. What caused it — inhaling smoke, bad diet, genetic traits, the sun or toxic chemicals — usually remains a mystery.

Short-term exposure to EtO can cause breathing problems and other acute issues. Longer term, the EPA says, “scientific evidence in humans indicates that exposure to EtO for many years increases the risk of cancers of the white blood cells, including non-Hodgkin lymphoma, myeloma, and lymphocytic [also known as lymphoblastic] leukemia. Studies also show that long-term exposure to EtO increases the risk of breast cancer in women.”

Terumo officials acknowledge national EPA data assessments saying there may be more risk of cancer in a given area over time. But, Terumo says, the key is that other government agencies have not found counts of actual cancer cases to be above normal rates.

Blake Darnell sits with his father Gordon and Chihuahua, Zoey, at Sunset Park in Lakewood on Jan. 17, 2023. Darnell, 32, had his lower left leg amputated after being diagnosed with cancer and acute lymphocytic leukemia in 2009. He attributes his diagnoses with toxic emissions from the nearby Terumo BCT medical equipment sterilization plant, seen on the horizon from Sunset Park in the next photo. (Olivia Sun, The Colorado Sun via Report for America)

Hypothetical dangers of ethylene oxide don’t tell the story of what Terumo has done to control the substance in its operations, company officials said, in interviews and on a tour of the plant. 

“Sterilization is the most regulated part of a highly regulated company within a highly regulated industry,” said Jessi Done, Terumo’s senior manager of sterilization services in Lakewood.

Terumo’s Lakewood plant makes blood drawing and infusion tubes and containers used in a number of medical settings, from blood banks to hospitals to apheresis centers. Before shipping, boxes of finished equipment are loaded into sterilization chambers. 

An injection of ethylene oxide gas permeates the shipping boxes and packaging materials as the medical equipment sits on large pallets, Terumo explained during a tour. EtO sterilizes the equipment over hours, and the boxes sit inside the sealed bays for hours longer while the gas dissipates. 

A vacuum system sucks nearly all of the spent gas to an internal scrubbing system, Terumo said. The product boxes continue to emit leftover gases for some hours, and Terumo washes the bay with clean air that is also sent to scrubbers. When employees finally open the chambers to remove products for shipping, the vacuum pulls any remaining traces of air away from the open end and sends it through vents to filters. Terumo notes that EtO traces are so low at that point, the employees aren’t required by OSHA to wear ventilators or masks.

About half of medical devices that must be sterile are treated with EtO, the Food and Drug Administration says. The gas is one of the few methods that penetrates all packaging and will not damage delicate plastics or glass materials. 

Sterilization is the most regulated part of a highly regulated company within a highly regulated industry.

— Jessi Done, Terumo’s senior manager of sterilization services in Lakewood

The FDA says it is continually studying new sterilization methods both to reduce EtO use and diversify sterilization options for medical device makers, including a pilot program studying gamma radiation.

In 2018, the EPA released an update to its national database of toxic chemical releases, focusing on 26 manufacturers around the nation using EtO at levels the agency said could pose added cancer risks to neighbors over time. Lakewood was one of those facilities. 

The Colorado Department of Public Health and Environment set up temporary air monitoring outside the Terumo buildings. The state’s measurements confirmed the EPA findings that there could be an elevated risk of developing cancer. But the state also conducted an epidemiological study of actual cancer cases in surrounding ZIP codes. They later announced there was no perceptible increase in cancer cases over the number expected in an average neighborhood.

The U.S. Environmental Protection Agency raised concerns when it disclosed data showing the risks of additional cancer cases from releases of ethylene oxide at the Terumo sterilization plant. State health authorities and Terumo say risks are different from actual cancer cases, and that epidemiology studies have not found elevated levels of cancer. (EPA Terumo/Lakewood website)

Terumo in 2018 noted it was operating well under permitted limits for EtO releases, but also added new safety measures. The company added equipment to remove more EtO before venting and circulate the last of the treatment bay air cycles through scrubbers. The system turns EtO into recyclable ethylene glycol. State officials said the new measures had significantly reduced detectable EtO outside the buildings, and considered the matter closed. 

Those efforts were voluntary, Terumo emphasizes, above and beyond any state or federal permit requirements. And now Terumo says it is doing even more, preparing to hook up a $22 million catalytic oxidizing system that will separate spent EtO gases into water and carbon dioxide. 

Terumo’s existing systems destroy more than 99% of EtO. The catalytic oxidizer system to be plugged in later in 2023 will eliminate 70% of what’s left, officials said. 

The risks of any remaining EtO must be placed in context, Terumo officials say. 

The EPA models potential risk for extra cancers, Done said. That doesn’t mean more people in Lakewood are actually suffering from cancer because of Terumo, Done said. The data models are meant to create targets for further study among federal, state and academic scientists on danger levels and solutions, she said. Like many risk models, Done said, the EPA’s EtO data starts with theoretical exposure levels. 

“It’s unlikely that a single person would have spent 24 hours a day for 70 straight years without leaving this area at all, but the agencies want to be protective of health, and the intent is to to identify areas for further studies,” Done said. “So I think that’s an important point.”

For any Terumo employees that may be exposed regularly to contact with EtO or the equipment that handles it, Colorado state health officials said workplace exposure would be handled by the federal Occupational Safety and Health Administration.

Terumo says plant monitors measure EtO at 16 points inside the plant 24 hours a day. Employees also wear personal monitors on badges. “Our efforts here exceed federal and state requirements,” Terumo spokesperson Christine Romero said. The state has never asked Terumo to do an EtO study on employee exposure, she said.

Blake Darnell, a former ski and snowboarding enthusiast, spent most of his time from age 18-23 in the hospital. (Olivia Sun, The Colorado Sun via Report for America)

Did the state miss something all along? 

It’s not just lawsuit plaintiffs who question those assurances. 

Colorado health officials are studying five possible locations for permanent toxic air monitors around the state to fulfill the demands of legislation passed in 2022 setting up tighter regulations of dangerous chemicals. Co-sponsor Rep. Chris deGruy Kennedy, a Democrat whose district includes the Terumo plant, and he said the state needs more tools to assess whether neighbors of industrial facilities like Terumo’s are truly protected.

“I do believe it’s important we do monitoring here,” deGruy Kennedy said. “Every time I talk to Terumo, they say, ‘It’s not us. It’s this bus depot that’s nearby.’”

Terumo’s campus is part of a light industrial and retail area north of 6th Avenue, wedged between residential neighborhoods to the west and east. Lakewood High School sits just to the southeast of Sunset Park, across Kipling Street.

Terumo and supportive trade associations do point out that ethylene oxide is produced by many things, including vehicle exhaust. 

“We can at least explore the possibility that if they’re right, OK, but if we can rule it out, take that talking point off the table and resume conversations” about whether the controls are effective,  deGruy Kennedy said.

Terumo and its predecessors on the Lakewood site have held air pollution permits from the Colorado Department of Public Health and Environment for decades, Air Pollution Control Division director Michael Ogletree said. The EPA reclassified ethylene oxide as a human carcinogen in 2016 and ratcheted down allowed exposure for the public and employees working with the chemical. 

Ethylene oxide worries exploded in 2018, when the EPA updated a national database of toxic air assessment based on 2014 data about EtO releases. The agency’s listing of 26 plants where neighbors are exposed to relatively high emissions prompted tense town halls with federal, state and industry executives in Lakewood and other cities. 

When the 2018 update came out, Ogletree said, state health officials “mobilized and sampled air for seven consecutive days” at Terumo. The state also set up monitoring to establish local background levels for EtO existing before additional Terumo releases were factored in. 

Terumo’s emissions were still below permitted levels, but worked with the state voluntarily on the new sets of controls for removing more EtO before venting the sterilization bays, according to both state and Terumo officials. The state returned for more monitoring late in 2018 and found a 20% reduction in EtO releases, Ogletree said. 

The air toxin monitoring bill passed last year gives state health officials new tools to assess the risks of specific chemicals, set limits in permits, and create six permanent monitoring stations chosen to assess the highest potential dangers in the state. Current state monitoring stations do not target acutely toxic chemicals, but rather measure an EPA-regulated set of combustion related, multiple-source air pollutants like ozone, nitrogen oxides, sulfur dioxide and particulate matter. 

“We’re not ruling out Terumo as a possible site,” Ogletree said. “It’s obviously on our radar.”

But in locating the new monitors, the state must calculate other factors. Those include historic pollution to disproportionately impacted low-income populations — such as around the Suncor refinery in Commerce City — and the level of risk from local pollutants. 

Duffey, leader of the neighborhood association, acknowledges that Terumo has taken steps to limit EtO emissions, but she wants independent monitoring outside the plant to help prove it. And, she says, neighbors want access to those measurements. 

“I don’t think asking for some monitoring is asking too much,” she said.


deGruy Kennedy said he understands Lakewood might not get one of the first set of new toxin monitors, and he agrees with the logic of prioritizing clearly impacted communities. Still, he said, debates over new permanent monitors don’t preclude the state from returning mobile monitoring equipment to Terumo to gather more data and reassure residents. 

Ogletree agrees. “We have the technology and resources to do that,” he said. “We’re keeping a very close eye on their activities,” including the latest EtO controls scheduled for 2023. 

As for holding Terumo to account for past behavior through the civil court system, deGruy Kennedy said his constituents deserve to be heard. 

“I do believe in the right of citizens to sue big corporations, to make sure that they’re doing what they’re required to do under the law,” he said. 

The lives of the plaintiffs 

Blake Darnell is accompanied nearly everywhere by a rotating team of formal and informal caretakers. His older brother, Gordon Jr., moved back home years ago to help while their dad worked.

Blake’s life is a series of visits with doctors trying to hold his body together, and lawyers trying to assign blame for why it started falling apart. One life he can control is that of Zoey, a trembly chihuahua Blake brings everywhere in a baby stroller. 

Darnell and his friends risked their necks a thousand times on the Sunset Park dirt jumps in the early 2000s. With his artificial leg and winter ice making the access paths treacherous, the Darnells have to stick to the overlook. “Those were really good days and good times,” Blake Darnell said. 

Dozens of other Lakewood residents have joined the legal battle to make Terumo pay for chronic medical conditions they attribute to living for years near ethylene oxide emissions. 

A group of plaintiffs including Ann Jordan filed a lawsuit in Jefferson County District Court in 2021, citing EPA toxic release records showing Terumo put more than 2,000 pounds of EtO emissions into the air every year from 2000 to 2018. Even after Terumo put in the new controls in 2018, the monitoring by state regulators still showed emissions “above the U.S. EPA’s acceptable limit” of EtO, the lawsuit claims. 

Jordan lived and worked less than a mile from Terumo at that time. She was diagnosed with breast cancer in 2012, the lawsuit said, which she attributes to ethylene oxide. 

Susan Kaberline, a plaintiff in another case, lived within a mile of Terumo, and was diagnosed with the rare blood disorder myelodysplastic syndrome in 2019, according to her suit. 

Many of the lawsuits cite the same EtO release statistics and potential elevated cancer risks at those levels in the neighborhoods around Terumo. They also cite various warnings about EtO exposure from government agencies and scientists dating back to the 1970s, including Illinois public health officials counting elevated cases of current cancers around Sterigenics’ facility in Willowbrook, near Chicago. 

The lawsuits claim that since at least 1994, Terumo and its predecessor companies in the Lakewood buildings such as Gambro “knew or should have known that the levels of EtO gas emitted from its facility would have a toxic, poisonous and deleterious effect upon the health, safety and well-being of people living and working in the community, and that these effects would be substantial.”

Blake Darnell with his Chihuahua, Zoey, on Jan. 17, 2023, at Sunset Park in Lakewood. (Olivia Sun, The Colorado Sun via Report for America)

Does a permit absolve a polluter from blame?  

Terumo says it has compassion for anyone struggling with cancer, leukemia or other disease, and that its products deliver life-saving treatments around the world. Terumo’s parent company is based in Tokyo, with 28,000 employees worldwide, including about 2,000 in Lakewood. The company would not comment on specific lawsuits. 

“Our Lakewood facility is operated in accordance with all known environmental, health and safety requirements,” a written statement from Terumo said. “Based on our review of the available data and information, we are confident that the facts and science will show that our operations are not harming residents near our Lakewood facility,” the company statement added.

If trials in ethylene oxide do move forward in the absence of more settlements, they are likely to play out on the spectrum of what it takes to “prove” something to a scientist versus what it takes to persuade a jury with a different standard of judgment. 

“Can anyone tell you whether that person got cancer from ethylene oxide? No,” said Tracey Woodruff, a former EPA scientist and currently a professor of reproductive medicine at the University of California San Francisco medical school. 

What plaintiffs often try to discover during “toxic tort” lawsuits, said Woodruff, who researches toxic chemicals like ethylene oxide but is not involved in any of the cases, is whether a company knew of dangers it didn’t disclose to the public. Personal injury suits targeting a new group of chemicals often consolidate into a new body of law and regulation, or “tort.” 

Tobacco companies have paid out billions in settlements from such cases. The herbicide maker Monsanto has lost judgments in the hundreds of millions from juries who agreed with arguments that the company knew of cancer-causing potential for years and “fought science.”

Ethylene oxide has one purpose: to kill things. So putting that kind of facility and emitting ethylene dioxide into the air, what’s it gonna do when it leaves the facility? It’s going to kill more things.

—Kurt Zaner, of Zaner Harden Law in Denver

Woodruff and other scientists have defended the EPA’s standards on ethylene oxide against challenges from the state of Texas, where petroleum refiners produce much of the EtO supply, and trade associations. A Texas commission ruled EtO was less toxic than the EPA maintains

The American Chemistry Council, an industry trade group, also stepped in to challenge the EPA and demand a lower risk tag for ethylene oxide. 

Woodruff, who helped the EPA develop its National Air Toxics Assessment models, backs the 2018 EPA revisions and says if anything they still underestimate the dangers.

Multiple scientists have told the EPA that the models may not yet factor in the heightened medical dangers of EtO and other chemicals absorbed during pregnancy. Ethylene oxide is one of the few chemical hazards the EPA has tagged with an extra warning about exposure among children, whose developing bodies can be more severely impacted by carcinogens, Woodruff said.

The Union of Concerned Scientists underlined EtO dangers in a report Feb. 7, zeroing in on a handful of locations around the nation where more than one large user of ethylene oxide is located. That includes Colorado, which has other sterilization companies on the Front Range. The report highlights sterilization facilities set in the middle of major population centers, including Terumo. 

The Terumo plant, the report notes, “is within 5 miles of roughly 267,000 people and 240 schools and childcare centers. The proportions of people of color and people with low income are also greater within 5 miles of this facility compared with the county overall.” 

The scientists also say epidemiologists, counting actual cases of cancer in a community rather than future risk, may be missing the contributions of EtO as one factor leading to common breast cancers.

“There’s a lot of breast cancer that’s probably not accounted for,” Woodruff said. In court cases, she added, companies will be challenged about whether they participated in industry groups’ campaigns against higher risk assessments. EtO is not used in all medical sterilization, and the FDA’s pilot programs studying alternatives are promising, Woodruff said.

Terumo said it is not a member of the American Chemistry Council, which has been criticized by researchers for challenging the EPA’s ethylene oxide data.

“Terumo Blood and Cell Technologies supports the EPA’s review of EtO emissions standards and has worked with EPA to provide data to assist it in its review of those standards. We have had continued conversations with the agencies and remain open to more,” company spokesperson Christine Romero said, in a statement. 

Zaner, attorney for Darnell and plaintiffs in other cases, anticipates Terumo’s defense will argue that the company heeded emissions limits at all times. But, Zaner said, just because a company has met a government standard doesn’t absolve it of potential negligence and liability in handling toxic chemicals. 

The companies before Terumo that built the Lakewood facility for sterilization in 1978, and Terumo in adding to the complex in the 2000s, should not have placed a toxic chemical source in a fast-growing area full of houses, day care centers and schools, Zaner said. 

“Especially schools,” Gordon Darnell Jr. said.

“Ethylene oxide has one purpose: to kill things,” Zaner said, noting that highly flammable ethylene oxide has also been used in thermobaric weapons, that disperse a substance and set it alight to create destructive shock waves. 

“So putting that kind of facility and emitting ethylene dioxide into the air, what’s it gonna do when it leaves the facility?” Zaner said. “It’s going to kill more things.”

CLARIFICATION: This story was updated on Feb. 17, 2023, to clarify how ethylene oxide is handled at Terumo’s Lakewood plant. In the current system, air from the sterilization chambers, aeration room and back vent is sent through an emissions control system before it’s released outside. In the catalytic oxidation system Terumo will bring online in 2023, ethylene oxide will be converted into water vapor and carbon dioxide. The story was also updated to clarify the settings in which the company’s products made in Colorado are most commonly used.

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Michael Booth is a Colorado Sun reporter covering health, health policy and the environment. Email: Twitter: @MBoothDenver