Traffic moves along Highway 526 in front of Boeing’s Everett Production Facility on Nov. 28, 2022, in Everett, Washington. (Olivia Vanni / Sound Publishing)

Traffic moves along Highway 526 in front of Boeing’s Everett Production Facility on Nov. 28, 2022, in Everett, Washington. (Olivia Vanni / Sound Publishing)

Boeing knew of ‘elevated’ miscarriage rate in ’80s, but followup fizzled

Company doctors found it “difficult” to link chemicals to worker ailments at Auburn facility.

Editor’s note: This is part of ongoing coverage examining the dangers of chemical exposure to Boeing workers in the Puget Sound region. According to records obtained exclusively by The Daily Herald in Everett, the aerospace company has attempted to study the toxicity of chemicals used in its factories — and their potential to impact worker health — with mixed results.

AUBURN — After a series of miscarriages among her pregnant colleagues in 1985, a shop steward in Plastics Fabrication was the first to ask the troubling question.

Women in building 17.05 of the Boeing Company’s Auburn plant began to wonder if the chemicals they used were to blame. Their concerns triggered a company study.

But the answer was neither simple nor definitive.

In short, Boeing’s health and safety experts found what appeared to be an “elevated” rate of miscarriages: 11 of 41 pregnancies among the cohort of study participants, or about 27 percent of cases, according to a health survey. The normal rate was more like 10 to 20 percent, according to studies cited by Boeing.

Further analysis found the worker sample size was too small to “conclude with certainty whether or not the overall rate of miscarriage in the Auburn Plastic Bench Mechanics is higher than the overall rate of miscarriage in the general population.” A corporate memo reported that “no single agent can be identified as a cause of miscarriage in this study,” but pointed to a few chemical products that were “implicated by this study as being associated with miscarriage,” records show.

The Environmental Protection Agency reviewed the results of the miscarriage study and opined that it warranted further research. However, according to depositions of Boeing officials this year, that follow-up never happened.

The internal documents were among hundreds of pages of historical company records discussed in the depositions, taken in a series of lawsuits claiming Boeing factory employees sustained reproductive harm from chemicals they handled on the job. The exposure resulted in “catastrophic” birth defects in the workers’ children, born between 1980 and 2014, the lawsuits allege. The families’ attorneys suspect there are many more people who suffer from lifelong health problems or genetic disorders because of the toxins their parents worked at Boeing manufacturing facilities during the past four decades.

Over the years, Boeing has tried to analyze the health repercussions of industrial poisons routinely used by its workforce, the records show. Yet some of these efforts fizzled before reaching any firm conclusions.

Company epidemiologists spent years building the foundation for a database to find links between specific chemicals employees used and workers’ health ailments, according to the testimony of Dr. J. Michael Muhm, manager of epidemiology for Boeing from 1987 to 1992.

But as Muhm explained in a June 7 deposition, “it was very, very difficult to link the chemicals with which employees worked to the employees.”

“It was not something that was reasonably done on a corporate-wide — or on a company basis,” said Muhm, who worked for Boeing until he retired in 2010. “… I think this was an intent, but I don’t believe we were ever successful at creating this database.”

The documents underscore the complexities of understanding the harm workers could suffer — and possibly pass on to their children.

“One of the realities of industrial workplaces is that unless the company chooses to do a study to determine whether the chemicals it’s using are causing adverse effects amongst its workers and the children of its workers, then it’s very hard for regulators and the scientific community to know what is going on and what health effects are occurring,” said plaintiff’s attorney Michael Connett, a partner at Waters Kraus & Paul who specializes in birth defect litigation.

That’s a massive conflict of interest, he explained.

If a study provides evidence that chemicals cause harm, “then the company is inviting liability,” Connett said. “So companies are disincentivized from doing studies that would bring to light the full spectrum of consequences of the chemicals it handles.”

Boeing has declined to comment on the lawsuits and depositions, citing company policy.

In court filings, the company has argued that the children’s birth defects were not caused by chemicals in its facilities, and that it has always taken measures to protect its employees from potential health hazards.

In October, the company reached terms on an out-of-court settlement with one of the plaintiffs, a North Bend woman born with a heart defect in 1980, when her mother worked at a Boeing Field factory.

Two other lawsuits, still pending, were filed by the families of two men who became fathers while working as mechanics at the Everett plant.

While reporting on the litigation, The Daily Herald obtained eight depositions of current and former employees, including more than a hundred exhibits of corporate memos, reports and scientific studies discussed by high-ranking company officials over the past 40 years.

‘Baseline data’

As early as the 1940s, there was recognition in the medical community that pregnant women are more sensitive to industrial chemicals than the general population.

A top doctor at Boeing warned the company president in 1980 of the disastrous potential of a long list of chemicals and urged improvements to the “industrial hygiene” program, The Herald has reported.

But the suggestion wasn’t well received by then-President Malcolm Stamper, noted Dr. Barry Dunphy, then the company’s occupational health manager. Dunphy remarked that Stamper “did not appear at all sympathetic or indeed faintly happy” about having “this organizational problem brought to his attention,” the deposition records show.

The Auburn Reproductive Health Survey marked a recognition by the company in July 1986 that more information was needed about the harmful effects of chemicals in use at its workplace.

Despite growing concerns about reproductive hazards childbearing women and their partners might encounter on the job, the survey noted, “many chemicals have not been studied for reproductive health effects.”

“The reasons for lack of information on reproductive effects of chemicals include insufficient data from animal experiments on most commercial chemicals and the difficulty of collecting valid information from studies of human populations exposed to chemicals,” says the survey report, written by a company epidemiologist.

The Auburn plant study considered dozens of chemicals, including some organic solvents already suspected of being dangerous to the reproductive system. On the list were toluene, xylene, petroleum distillates and methyl ethyl ketone — some of the same organic solvents named in the recent birth defect lawsuits.

Following the initial 1986 survey, Boeing began evaluating more of its materials for the potential to cause reproductive harm to mothers and fathers working in its factories, records show. An internal report drafted in 1987 outlined the company’s plan to build a list and “continue to add to our information profile” as scientific knowledge advanced.

“At the same time, an increasing number of chemicals are being introduced into the workplace and new industrial processes/tasks are utilized,” says the report. “Evaluation of potential exposure should keep pace with these developments and this represents the baseline data upon which future studies can be performed.”

‘Study the relationship’

Two years after the first report on the Auburn plant miscarriages, the company’s corporate health and safety manager documented mixed conclusions about the data in a 1988 memo, addressed to the Auburn Human Relations and the Auburn Executive Safety Council.

“The overall rate of miscarriage in the organizations included in this study is not conclusively higher than that in the general population, but the results of this study do more to support that contention than to refute it,” says a draft of the memo.

Chemicals associated with higher rates of miscarriage included solvent components in “Frekote 700,” a parting compound, and “Scotchweld adhesive film AF 163-2K.” Miscarriages were also clustered among women whose jobs involved heavy lifting.

The memo noted the study’s limitations, including its small size. It also only accounted for “medically confirmed” pregnancies, so it could have missed early-term miscarriages.

“My understanding of the conclusion of the study was that there wasn’t a significant difference in the number of miscarriages in this group compared to the general population,” said Boeing Senior Toxicologist Brittany Weldon when she was deposed to speak on the company’s behalf in August.

She was not aware of any further study of the miscarriages.

But according to the January 1988 memo, Boeing had plans to revisit the issue.

“The Boeing Company is currently developing an Employee Health and Safety Module as part of the Integrated Employee Record System, a computerized data base which will enhance our ability to study the relationship between exposure to various hazardous agents and adverse medical outcomes,” wrote M. H. Stewart, Boeing’s corporate safety and health manager, in the memo. “When this system is functional, a study of the Auburn area will be repeated to reassess the rate of miscarriage in Plastic Bench Mechanics.”

That spring, Boeing also shared these plans with the EPA when disclosing the Auburn study results, as required by the 1976 Toxic Substances Control Act. The EPA asked Boeing to report back with any further findings and suggested that there were other outcomes, such as low birth rate, that Boeing could examine for signs of reproductive harm.

“Boeing’s investigations demonstrate the difficulty involved in studying reproductive hazards in the workplace,” says an EPA report from April 1988.

“Although it cannot be determined that any particular chemical exposure or process or workplace activity was the cause of miscarriages among the employees at this Boeing facility,” the report continues, “the studies do signal the need for a more extensive examination of the rate of miscarriages at the facility and suggest the need for a monitoring program for workplace exposure to numerous chemicals.”

‘White with dust’

In the 1980s and 1990s, Boeing faced mounting pressure for more information about the connection between chemicals and workforce maladies. Controversy erupted in 1987 over the use of phenol formaldehyde resin, a component in a woven fiberglass cloth that the company began using that year to meet Federal Aviation Administration regulations on flammability.

Though the company discontinued the use of the chemical the following year, it faced the blowback for the next decade, including criticism for its handling of related workers compensation claims and scrutiny from regulators. A lawsuit, brought by sickened workers, led to a landmark state Supreme Court ruling and — ultimately — a multi-million dollar settlement.

When the company began testing the new material at the Auburn plant in February 1987, a supervisor noted employees “complained of dizziness, dryness in nose and throat, burning eyes, and upset stomach,” according to court records in the lawsuit.

There was an “obnoxious odor,” according to the court records, and the air at the production facility was “white with dust.” The supervisor remarked that he expected the problem would only get worse “as temperatures rise and production increases.” Records show he asked for improved ventilation, but management denied the request, saying odors didn’t warrant the cost of the upgrades.

The problem did, indeed, get worse, according to court records and media reports. Workers started to pass out on the job.

The company discontinued the use of phenol formaldehyde in December 1988, the Seattle Post-Intelligencer reported.

Dozens of workers filed claims with the company’s in-house insurance, saying they had been sickened by the chemical during the short time it was in use. Boeing questioned the legitimacy of many of them.

A physician panel, assembled by the company to review the claims, opined in 1989 that some of the physical symptoms were likely the result of anxiety, and there was no clear link between the chemical and the health problems.

The complaints fueled a growing recognition among doctors that more research was needed to understand the impact of industrial toxins on workers’ health. Some doctors adopted the term “multiple chemical sensitivity syndrome” to refer to chemically induced illness. However, many in the mainstream medical community didn’t accept the term as a real diagnosis. The concept remains controversial today.

Fourteen of the Auburn factory workers took their concerns to King County Superior Court in 1991. They sued the company, alleging they suffered lasting injuries and disabilities because of Boeing’s “deliberate intent to injure” and “outrageous conduct.”

The plaintiffs accused the company of removing chemical labels, harassing employees who sought protective gear, threatening to fire those who sought medical restrictions, and using workers as human experiment subjects without their consent. They also alleged the company would clean facilities and ventilation before regulatory inspections to skew test results.

The Washington State Supreme Court remarked in a 1995 ruling that the case was the first to reach the court “in which the acts alleged go beyond gross negligence of the employer, and involve willful disregard of actual knowledge by the employer of continuing injuries to employees.”

The landmark ruling in the case, Birklid v. Boeing Co., expanded the ability of workers to sue companies for injuries they sustained on the job. The state’s highest court held the plaintiffs “demonstrated facts sufficient to justify a jury in finding a deliberate intention by Boeing to injure them.”

“Boeing contended that the workers were not exposed to toxic chemicals beyond safe levels,” the ruling said. “The plaintiffs note, however, that regardless of so-called ‘safe’ levels of exposure, Boeing anticipated that those levels would make its workers sick, and, in fact, the workers became sick.”

The company settled the case out of court for an undisclosed amount, according to a 1997 report by The Seattle Times. One source told The P-I it was in the millions of dollars.

‘High exposures’

Amid the controversy over phenol formaldehyde, worker unions and scientific experts questioned whether regulations were enough to protect workers, given that federal officials found levels of the chemical passed air quality tests at the Auburn plant.

Deposition records in the recent lawsuits also highlight potential shortfalls of regulatory limits on chemicals in workplace air — especially when it comes to birth defects.

The plaintiffs’ attorneys have argued that federally accepted standards weren’t designed to protect everyone.

As of 1991, Boeing’s Occupational Health Examination Guide for Physicians acknowledged that “the potential for adverse reproductive effects were given only minimal consideration” in establishing widely used safety limits for worker chemical exposure.

“Nevertheless, if exposures are maintained within these limits, the possibility of any adverse reproductive effects will be minimized,” says the guide.

A 1990s-era “instructor’s guide” for Boeing’s hazard communication training advises that chemicals can still cause adverse health effects, even below legal thresholds set by the U.S. Occupational Safety and Health Administration.

For decades, OSHA has required companies to inventory their chemicals and disclose the risks of each to its workers.

“For many substances, exposure below the limits can be hazardous,” says the instructor’s pamphlet, created to guide factory worker training. “In addition, people vary a lot in their response to chemicals. There are always people who will react to even low concentrations of chemicals.”

As the pamphlet explains, the only way to know if someone’s exposure to a chemical exceeds the legal limit is monitoring — by measuring the concentration of the chemical in their breathing zone.

The most effective ways to protect workers from overexposure include “replacing hazardous chemicals with safer ones” and “local exhaust ventilation are the best controls,” says the guide. Boeing also instructed workers on when and how to wear personal protective equipment, or PPE, such as gloves and respirators.

But protective gear can only do so much, the instructor’s guide says.

“It does nothing to remove chemicals from the environment,” it says, “so that if the PPE is no good or fails, high exposures could result.”

‘A very weak type of study’

As a Renton-based corporate epidemiologist, Dr. Muhm tried to find data sources to analyze the health of Boeing’s workforce in the late 1980s and early 1990s, he testified. His team laid the groundwork for an analysis of employee mortality data for any “unusual” trends among the company’s employees or subgroups of workers.

“That was an end point that was fairly definite and could be used to determine if the employees of The Boeing Company had health experiences similar to the general population or higher,” he explained. “… The company used a number of toxic chemicals, and clearly we were interested if there was any adverse effects of those.”

The epidemiology group collected employee death certificates showing how current and former employees died, he said. The group also gathered corporate illness and injury statistics, as well as some health information from the employee health insurance provider.

“There were efforts to modify externally sourced databases and make them work in the Boeing environment,” Muhm said. “That was an exceedingly complex and, for me, frustrating effort that had never (come) to pass.”

Muhm said there might also have been some “rudimentary analysis” when he was a manager of the epidemiology group, but said that he did not remember the results.

“The best we could do at that point was called a proportionate mortality study where you looked at the portions of deaths out of the total number of deaths due to a certain cause, and determine whether or not those proportions were similar to or different from that in a standard population and as a very — a very weak type of study,” he said.

Toward the end of his time in the epidemiology group, he was reassigned to a “corporate-wide search” for any documentation of negative health effects that the company had failed to turn over to regulators.

The Toxic Substances Control Act required such documents be turned over to the EPA, at a price of roughly $25,000 per day late per document. However, the federal agency had announced an amnesty program allowing companies to turn them in without penalty, according to Muhm’s testimony. Muhm said he didn’t remember exactly how many documents he gathered that met the legal reporting requirements — or what they said.

But what he found, he testified, was enough to save the company millions.

‘By submitted diagnosis’

From 1992 to 2000, Muhm served as manager of Boeing Occupational Health Services, in the medical department. He oversaw a program “responsible for testing and monitoring health of 40,000 employees,” according to his curriculum vitae.

During his time in the role, the company obtained employee insurance claims data from King County Medical, deposition records show.

“Occupational Health Services has recently begun processing the Boeing employee insurance claims data received from King County Medical,” Muhm wrote in a 1994 internal memo to the company’s medical director. “To date we have counted the numbers of employees submitting claims, and the number of claims submitted, by submitted diagnosis. This provides information that is of value to other physicians in Boeing Medical.”

Attached to the memo was a one-page “sample report” that listed employee claims data for 200 different cancers, diseases and other health conditions from 1987-1993. However, the one-page list lacks context, such as the total number of employees whose data was sought, or the baseline prevalence of the diagnoses in the general population.

In his deposition, Muhm said he could not recall any further analysis of the data.

“Whether or not we went beyond this, I don’t know,” Muhm testified when asked about the numbers, “but we did get access to this private insurance data.”

In the mid-1990s, the company also contracted with the University of Washington to study the incidence of lung cancer among Boeing workers who used chromium.

The study did not rely on insurance claims data, though. Instead, the cancer data came from Fred Hutchinson Cancer Research Center’s Cancer Surveillance System, said Muhm, one of the study’s authors.

The study cost Boeing about $30,000, according to a contract with the university. Boeing provided the school with employee job history data, and UW agreed not to identify Boeing in the study, published in 1996.

The study cohort consisted of 2,500 workers who had spent at least six months in jobs involving hexavalent chromium exposure from 1974 to 1994. Among them, researchers counted fifteen cases of lung cancer and four other cases of respiratory cancer.

“Although based on few cases, an elevated lung cancer risk was found in subjects who had worked for 5 or more years as a chrome plater or surface processor tank tender … and sander/masker or polisher,” the study concluded. “A clear association was not observed between chromate exposure and the risk of lung cancer in this population of workers.”

Today, Chromium-6, or hexavalent chromium, is widely considered carcinogenic to workers. According to OSHA, the longer a worker is exposed, the more likely they are to develop lung, nasal and sinus cancer.

‘Historically exposed’

For years, Boeing also collected data on employee health through “medical surveillance,” or health monitoring, as part of its occupational health and safety program.

According to the 1991 physicians’ exam guide, these periodic examinations were required for employees who were exposed to chemicals over certain thresholds, established either by law or the corporate medical director. Sometimes, the exams included “biological monitoring” tests of a worker’s blood or urine.

As a result of new OSHA regulations in the 1990s, Boeing was required to offer medical screenings to employees who worked with materials containing cadmium, records show.

In 1994, Boeing began testing employees who were being exposed to cadmium on the job.

As of August of that year, more than 500 Boeing Puget Sound employees had been tested, according to an internal company memo. About 10 of those tests yielded abnormal results, Muhm wrote in the memo.

“Boeing’s tested population continues to be very similar to the OSHA non exposed populations in all measures,” says the memo.

With promising early results, the company initially hoped to get a “variance from the requirement to identify and biomonitor historically exposed employees,” records show.

But they encountered resistance from the union representative, who still wanted to see testing results from employees who might have been exposed in the past. Muhm was involved in identifying who needed to be tested to comply with the new rules, according to his deposition. As he confirmed in his deposition, as more time passed, cadmium levels measurable in those employees’ bodies would diminish.

To meet the regulations, Boeing began offering medical screening to employees whose past assignments involved potential exposure to cadmium for five years or more.

In January 1995, the company started by mailing screening paperwork to “historically exposed” workers in Everett. Those results, too, largely came back normal, records show.

But at Muhm’s recommendation, employees considered “historically exposed” were given the chance to opt out of screenings.

“In this case, the exposures no longer exist for historically exposed employees (or they would be currently exposed), and the information gained by the testing will have little/no effect on their health,” Muhm wrote in a 1994 memo.

“It will have more of an impact on the company’s liability,” he added, “should any of these employees develop renal failure or lung cancer somewhere down the road.”

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