The Clean Room’s Dirty Secret

The semiconductor industry prides itself on its high-tech ‘clean rooms.’ But as a growing number of workers are finding out, the state-of-the-art protections are meant to safeguard microchips, not humans.

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By all measures, Armida Mesa was an unlikely candidate for breast cancer. She is Latina (Hispanic women have a lower rate of the disease than most ethnic groups); she has given birth to two sons (childbearing also lowers susceptibility); she doesn’t smoke or drink; and neither her mother nor any of her seven sisters has any history of the disease. Why Mesa beat the odds and was diagnosed with cancer in 1984 at age 40 will never be known for certain.

Mesa, now 57, believes she knows why she got sick-and why her co-worker Suzanne Rubio died of breast cancer at age 36, and why several more of her acquaintances also developed cancer. They all worked at an IBM semiconductor plant in San Jose, California, making the silicon chips that run computers, cell phones, and other high-tech products. Now, along with 250 other semiconductor workers and their families, Mesa is trying to prove that the toxic mixture of chemicals used in high-tech factories has caused cancer in workers and birth defects in their children-and that their employers knew of the hazards but did not act to protect them.

“This is a forgotten group of workers,” says Dr. Joseph LaDou, director of the International Center for Occupational Medicine at the University of California at San Francisco, who has studied the industry ever since large-scale semiconductor manufacturing began in the 1970s. In the United States, nearly 300,000 people work in semiconductor plants; about one-quarter perform jobs that put them in routine contact with the toxic chemicals that are used to produce chips. Worldwide, the total number of semiconductor workers is estimated at more than 1 million, with US companies like Motorola and Intel dominating the market and investing billions each year to build new plants in places like Malaysia, the Philippines, and China.

As the industry continues to expand, LaDou predicts that health problems among workers, many of them women and minorities, will mushroom. “It’s quickly going to become a much larger problem than anyone ever conceived,” he warns. “We could be looking at an epidemic larger than what we went through with asbestos.”

In the “clean rooms” where chips are made, workers don protective clothing, including head-to-toe “bunny suits.” But the garments are not meant to safeguard humans; they are designed to keep impurities from contaminating the chips. Air is constantly recirculated, but the filters trap dust, not chemical fumes. Over the course of their shifts, workers breathe or come in contact with dozens of known or suspected carcinogens, including toluene, cadmium, arsenic, benzene, and trichloroethylene. They also can’t escape the compounds created as the various chemicals combine-mixtures whose toxicity has never been tested, except on them.

Industry representatives say workers are exposed to toxins only within the limits set by government agencies such as the Occupational Safety and Health Administration (OSHA). But those rules, health experts and worker advocates note, don’t take into account real-life conditions in factories, where dozens of hazardous substances may permeate the environment at any given time. As workers begin to fall ill with a variety of diseases, they are starting to raise questions about the efficacy of the standards-and about whether their employers knew of the hazards and failed to warn them. At least 250 people have filed lawsuits against high-tech companies, chiefly IBM and National Semiconductor, in New York and California. Also named as defendants are the makers of some of the chemicals used in chip manufacturing, including Union Carbide, DuPont, and Eastman Kodak. The workers claim that the toxic soup inside the production areas has triggered high rates of miscarriages, birth defects in children born to employees, and cancer. “Clean had nothing to do with safe,” says Amanda Hawes, a San Jose attorney who represents many of the workers. Like many IBM employees, Armida Mesa has a distinct memory about her 24 years at Big Blue. Company officials “told us that, number one, they would always look out for you as an individual,” she recalls. “We trusted them totally.”

Mesa felt lucky to land a job at IBM’s Cottle Road disk-manufacturing plant in 1968, when she was 23. That was long before the area was called Silicon Valley, when the hills around San Jose were still dotted with orchards and farm elds. The plant, opened in 1959, was among the rst of a ßood of computer firms-Intel, Hewlett-Packard, National Semiconductor, NEC Electronics-that would eventually set up shop in the valley. The manufacture of semiconductor chips involves hundreds of chemicals, many with long, hazardous track records. Silicon wafers, each about the size of a dinner plate, are imprinted and etched with various acids and solvents to create a three-dimensional pattern that ultimately will carry electric signals through a maze of microscopic wires. At each step, they are immersed in a chemical bath to render them smooth; to alter the chips’ conductivity, chemicals such as arsenic are applied to portions of each wafer.

For nearly a dozen years, Mesa worked in the clean room and on the chip assembly line. She and her coworkers were given protective gowns and shoe covers at rst, then full bunny suits. “The gloves we were wearing got sort of sticky when we’d rinse the chemicals off [the chips],” she recalls. “Sometimes we wouldn’t wear the gloves because they didn’t work. We’d just put our hands in and pull the stuff out.”

Mesa says she often felt slightly ill while working, and she started suffering from headaches and sinus infections, something she had never experienced before. She was diagnosed with breast cancer in 1984, underwent a lumpectomy, and went back to work. But in 1991 the cancer returned, and Mesa had a mastectomy. She left IBM the next year. It wasn’t until later, Mesa recalls, that she heard of other Cottle Road employees, including several of her immediate co-workers, who had developed cancer. “I thought, ‘My God, is this contagious?'”

In 1998, after learning that some of those co-workers were suing IBM, Mesa-who now works as a county law clerk in San Jose-filed her own claim. About 50 such lawsuits are now pending in California and about 200 more have been filed by employees at IBM’s plants in East Fishkill, New York, and Essex Junction, Vermont. (In addition to Silicon Valley, major semiconductor manufacturing centers include New York’s mid-Hudson region; Massachusetts’ Route 128 corridor; Austin, Texas; and Portland, Maine. IBM, based in Armonk, New York, has been the focus of most of the litigation to date because of its long production history.) An IBM spokeswoman declined to comment on the cases.

The rst of the lawsuits to get to court was filed by Faye Calton and Michael Rufng, who worked in clean rooms at the East Fishkill plant. Their son Zachary, now 16, was born with severe skeletal deformities; in 1996, Rufng and Calton sued IBM, asking for $40 million in damages. The case was settled shortly before trial last year for an undisclosed amount, in an agreement that prevents the parties from talking about the lawsuit. At the time, IBM issued a statement saying that it “firmly believes, based upon state-of-the-art science, that it had no liability in this case and that it did not act wrongfully in any manner.” Eight more lawsuits against the company in New York are scheduled for trial later this year. Trial dates have not been set in the California cases against IBM.

Though the specifics vary, all the plaintiffs have one claim in common: that IBM and other high-tech companies ignored scientific studies suggesting that the chemicals they used could endanger workers. In the early 1980s, researchers reported that glycol ethers, chemicals widely used as solvents in the semiconductor industry, could cause reproductive problems in laboratory animals. Subsequent studies, including one sponsored in 1989 by the Semiconductor Industry Association, showed that semiconductor workers exposed to the chemicals suffered miscarriages at double the expected rate.

The industry began phasing out use of glycol ethers in the mid-1990s. But many other chemicals linked to reproductive health problems, including xylene, trichloroethylene, phenols, and acetone, remain in use. In 1991, a Canadian study of pregnant women exposed to workplace solvents similar to those used in clean rooms found that 13 out of 125 had given birth to children with major congenital malformations, compared to only 1 out of 125 in jobs involving no solvents.

The industry’s high rate of reproductive health problems is particularly alarming, researchers say, because semiconductor manufacturing has increasingly become women’s work. Wages in the industry are relatively low (in 2000, median hourly pay for US workers was $12), but large companies like IBM offer good benets and 12-hour shifts that are attractive for workers with families.

In recent years, experts have grown worried about another health risk for semiconductor workers-cancer. As far back as 1985, an IBM chemist wrote a memo to his bosses warning that a disproportionate number of his co-workers had various forms of the disease. In the years since, a number of studies have found that long-term workers in the electronics industry are at increased risk of developing certain cancers. But concern has increased in the wake of a British government survey, released last December, that found elevated rates of breast, lung, brain, and stomach cancer among more than 4,000 workers at a National Semiconductor plant in Greenock, Scotland.

Cancer rates among US semiconductor workers have never been surveyed; a planned 1998 study by the California Department of Health Services failed because semiconductor manufacturers refused to cooperate. “The industry felt there was not enough scientific evidence linking work in a clean room to cancer,” says Molly Tuttle, a spokeswoman for the Semiconductor Industry Association, “and it seemed inappropriate to get involved in a study like that.” In 2000, the association convened its own panel of scientific advisers to determine if more research should be done. Its ndings have not been made public, but Tuttle says industry leaders are taking the issue “very seriously.” Yet a growing number of health experts are not content to wait for companies to take action. A group of US researchers, including LaDou and Dr. John Bailar III, chairman of the Department of Health Studies at the University of Chicago, has urged the World Health Organization to conduct an international study of cancer rates among clean-room workers. An increase in job-related health problems in the industry “should be a matter of broad and deep public-health concern,” Bailar wrote in a January letter to the who’s cancer agency. At particular risk, he warned, were workers in developing countries, where job-safety rules are often weak and where chip factories routinely use chemicals and equipment that are no longer considered safe in the industrialized world. Bailar, who specializes in medical statistics and once served as editor-in-chief of the National Cancer Institute’s scientific journal, says he was prompted to act after reviewing research including the Scottish study, which he found “very worrisome.” “You look at the numbers in this tiny study,” he says. “They were able to detect pretty strong signals of excess cancers in four different sites [of the body]. The data doesn’t prove an excess risk, but it is strongly suggested.”

Miscarriages, birth defects, and certain cancers may all be triggered by the same chemicals, notes Bailar-toxins that, for reasons unknown, damage the human genome. But because the health problems often don’t develop until years after a worker has been exposed, establishing a direct cause-and-effect link has been difficult. “The sad thing is, people have been raising this with the industry for 20 years,” says Dr. Bruce Fowler, director of the toxicology program at the University of Maryland. Had there been a concerted research effort back then, he notes, some of the questions the workers are now raising in lawsuits could long have been answered by now.

Ed Matuszak began working for IBM in January 1988. With a bachelor’s degree in chemistry and a master’s in materials science, he had received no fewer than five job offers from Big Blue, according to his wife, Susan. Convinced that his family would be happiest in northern Vermont, he accepted a job at IBM’s plant in the town of Essex Junction, near Burlington. He was in charge of maintaining the sophisticated equipment in the clean rooms; the work meant so much to him, Susan recalls, that after a 12-hour day on the job, he’d often talk to colleagues on the phone at night.

One day in March 2000, Matuszak came home complaining of the flu. A few hours later, he began thrashing about in a seizure so violent that he dislocated his shoulder. His wife assumed it was caused by a high fever. But in the emergency room that night, a surgeon told her that tests had found “something” that would require a closer look in the morning. “They did an MRI,” recalls Susan. “The neurosurgeon was very blunt. Ed had a brain tumor and might have 5 to 10 years to live.” As Matuszak, 40, underwent surgery and radiation treatments, he asked his colleagues to bring him a laptop so he could stay in touch with operations at the plant. The doctors were optimistic; Matuszak talked of returning to work.

One day, during a rehab session, the therapist gave Matuszak a simple arithmetic test. He couldnÕt add the numbers. “I froze,” Susan recalls. The tumor was growing again. That June, Matuszak suffered a massive seizure; he was dead four weeks later. What the Matuszaks didn’t know at the time was that, in another room of the same hospital, one of Ed’s co-workers, Mike Beaudry, was also struggling with a fatal brain tumor. He died last year.

Whether the two men’s illnesses were connected with their jobs, Susan Matuszak says, was a question workers at the plant didn’t seem to want to ponder. “They wouldn’t say anything,” she recalls. “I guess they thought it didn’t affect them.” Both Susan and Beaudry’s mother are now suing IBM.

Men in jobs like Ed Matuszak’s appear to be at greater-than-average risk of developing brain cancer. A 1996 study of more than 10,000 deaths among IBM workers between 1975 and 1989 showed an elevated rate of brain tumors among male engineers and technicians who had been with the company for 10 years or more. Without further investigation it’s hard to say what caused the increase, says Fowler, but the numbers suggest that “IBM’s got a problem.” In addition, at least two other studies have shown an increased risk of brain tumors among workers in the electronics industry; the largest increase was discovered in the Scottish survey, which found brain cancers appearing in male workers at four times the expected rate.

Still, those statistics don’t answer the most pressing question for people like Susan Matuszak-whether particular workers got sick or died because of their jobs. Proving that specific chemicals used in clean rooms are the direct cause of specific illnesses is a Herculean task, given that the cases involve a dozen or more diseases and more than 100 chemicals covered by federal health and safety guidelines.

As their lawsuits proceed, the workers will also have to counter the industry’s defense: that semiconductor work is one of the safest manufacturing jobs in the nation. Semiconductor makers cite US Bureau of Labor Statistics data showing that semiconductor manufacturing has the sixth-lowest rate of on-the-job injuries among nearly 200 industries in its category. But the data measure only on-the-job injuries and illnesses, not chronic diseases that may take years to develop. Nor do they count reproductive disorders or genetic problems in employees’ children. Those omissions-particularly in an industry with a young, predominantly female workforce and a high turnover rate-make the data misleading, critics say, if not ßat-out wrong. Yet government regulators have taken a hands-off approach to the high-tech industry. Federal agencies charged with overseeing workplace safety have not conducted studies or special monitoring efforts in semiconductor plants. OSHA representatives say the companies’ “clean safety record” has made the industry “low priority” for regulators. “I am so frustrated by the position that we don’t have a problem,” says Hawes, the San Jose attorney. “I’m always being told, ‘You’re wrong, you’re misled. Show us the body count and then we’ll do something.’ We’ve been through this with this industry for a long time.”

Some veteran industry watchers believe it may take widespread, and expensive, litigation to force change. “If the employer doesn’t do what he’s supposed to do, and the government doesn’t step in, then in come the lawyers,” said LaDou. “They’re the last resort.” Even so, Fowler notes, it will likely be years, if not decades, before the medical, environmental, and legal issues are nally resolved. In the meantime, the industry will keep expanding, in the United States and overseas-and workers who fall ill will be left looking for answers. “Remember,” says Fowler, “these were just people who needed a job.”


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