(FORTUNE Magazine) – IN THE EXPANDING DEBATE over the safety of video display terminals, what's most startling is how little each side really knows. One example of the poor quality of the information being propounded: A recent California study found that pregnant managers who use terminals up to 20 hours a week were 70% less likely to have a miscarriage than peers who didn't sit before a VDT. That's right, 70% less likely. This doesn't mean VDT use is beneficial. The same study provoked widespread concern with its finding that the risk of miscarriage shot up 140% among clerical workers who use VDTs more than 20 hours a week. The debate, while not shedding much light, is putting steadily more heat on the business community. After years of trying, legislators are finally enacting restrictions on use of VDTs. Worried employees, especially women, are asking tough questions that companies need to answer, if only to avoid lawsuits later on. Increasingly unions are demanding contract provisions governing the use of VDTs. New studies on animals are raising troublesome concerns about the biological effects of VDT radiation. But with a huge human population potentially at risk, amazingly few follow-up studies are under way that could help assuage fears or suggest protective measures. And while the debate over radiation continues, much remains to be done in the workplace to address less exotic health problems known to be associated with VDTs, such as eyestrain and musculo-skeletal disorders. The benefits of video display terminals are indisputable. About 15 million are in use today in offices, factories, and homes across America, dutifully arraying data for all manner of computerized systems. The ubiquitous boxes have made a wide range of tasks, including the writing of this story, immensely easier. We sit and stare at the glow much as our ancestors attended to the cook fire, with patience and intensity. Since the late Seventies, though, suspicions have been aroused that these modern-day glowing hearths may radiate something less benign than gentle warmth. Scattered reports began reaching health officials that VDT operators from some workplaces suffered more miscarriages than normal in the overall population. But the few studies that had seriously focused on VDT workers seemed to dispel fears. Then, in June, the Kaiser Permanente Medical Care Program in Oakland published the research indicating that pregnant clerical workers who spent more than 20 hours a week on VDTs had greater than twice the chance of miscarrying as other clerical employees. The story was picked up as far away as Peking. Says Jeanne Stellman, a Columbia University professor of public health who runs the Brooklyn-based Women's Occupational Health Resource Center: ''I'm now getting calls from women all around the country asking me if they should quit their jobs if they're pregnant.'' Her answer: No, based on the evidence so far. Michael Polen, one of three researchers who worked on the Kaiser report, says: ''I regret that our study has increased the level of fear, and I think that's unwarranted. All we can say for sure is that we need more studies.'' In one respect the evidence on VDTs is sufficient and clear: It shows that operators will be uncomfortable, unhealthy, and unhappy unless they employ certain work practices and physical arrangements. These practices can be lumped under the heading ''ergonomic'' -- meaning engineered for human needs. Studies have shown that workers who spend long hours at a VDT suffer increased eyestrain as well as musculo-skeletal problems. A study financed by the National Institute of Mental Health and headed by Stellman found that job satisfaction among office workers declines in proportion to their use of VDTs, with full-time VDT operators complaining the most of physical ailments, unreasonable workloads, and a lack of say about their jobs.

Employers need to pay more attention to the VDT issue. Says Richard Victor, executive director of the Workers Compensation Research Institute, a Cambridge, Massachusetts, outfit that gets money from the insurance industry: ''This could be absolutely nothing, or it could be something that makes asbestos look small. We just don't know. So companies should be investing in information now.'' No employer or VDT manufacturer has yet been found liable for injuries suffered by an operator claiming injury from one of the machines. But 27 telephone operators at Mountain Bell in Denver have filed a complaint against Computer Consoles Inc., a VDT manufacturer. They charge that ergonomic defects, including hard-to-depress keys, caused them to develop carpal tunnel syndrome, a potentially crippling nerve disorder of the wrist. The greatest fears in the VDT debate center on radiation, the issue about which least is known. At first, suspicion focused on ionizing radiation such as X-rays, which can harm people by breaking the chemical bonds in the molecules of their tissue. But tests demonstrated that VDTs did not increase exposure to this type of radiation. So speculation has shifted to non-ionizing radiation, a much weaker form that cannot break molecular bonds but may still do damage in as yet unidentified ways. VDTs emit non-ionizing radiation as pulses of a very low frequency electromagnetic field. Until recently most scientists presumed any danger was impossible at the weak levels of radiation emitted by a VDT. But in June a study financed by the U.S. Office of Naval Research reported finding a significant increase in abnormalities among chicken embryos exposed to very low frequency pulsed magnetic fields. Less rigorously conducted research in Sweden has found deformations in mouse fetuses following exposure to electromagnetic fields very similar to those emitted by VDTs. Though these studies prove nothing about VDTs and people, they do suggest that magnetic fields at VDT frequencies can have a biological effect. It's all the more surprising, then, that studies aren't being done on the potential radiation danger to humans from VDTs. A promising study seeking to correlate the outcome of pregnancies with exposure has been proposed by researchers at Mt. Sinai Medical Center in New York, but this spring the National Institutes of Health, pressed for funds, at least temporarily turned down the $3.2 million project. THE KAISER REPORT didn't measure radiation and found that miscarriage risk increased significantly only for clerical workers using VDTs, not for women in other jobs who were also heavy users of the machines. According to the Kaiser researchers, stress associated with a poorly planned VDT work environment could explain the results as easily as radiation. Though the research so far gives cause for concern, many VDT manufacturers and some big corporate users tend to be remarkably sanguine. Lawrence Zippin, executive vice president of the American Insurance Association and chairman of the Center for Office Technology, a coalition of corporations making and using VDTs, says flatly: ''The scientific evidence to date proves to us that there's no radiation hazard. There's no need for further studies.'' Zippin points to epidemiological studies that found no significant risk and calls them conclusive. Responds Columbia's Stellman: ''That sort of statement just makes the public more anxious. Even though the people in the industry say it's absolutely safe, I think they're scared and don't trust what the results of an outside study would be.'' Louis Slesin, editor of VDT News, a publication recognized for its authority on health and safety issues, agrees: ''I'm forced to the conclusion that the manufacturers and government just don't want to know.'' Some industry experts appear to be growing more sensitive to the nuances of the debate. Robert Bettendorf, IBM's point man in the VDT controversy, admits it was hard for him to accept that science couldn't prove the technology absolutely safe, though he personally has no doubts. ''I wanted the proof positive, but I eventually realized we couldn't get that,'' he says. ''Whether or not we feel VDTs are safe, the issue remains.'' IBM is the only manufacturer now helping to pay for independent research on VDT radiation -- specifically a carefully controlled study at the University of Toronto that will expose pregnant mice to very low frequency electromagnetic fields at varying intensities and then evaluate the effect. Bettendorf maintains that it's important to establish the level, if any, at which the radiation has a biological effect, so manufacturers can ensure that emissions from their terminals stay well below it. In the light of all this uncertainty, what should a responsible company be doing? The height of prudence would probably be to deploy only terminals specially designed to reduce emissions. Such protection is not currently offered in the U.S. by any manufacturer -- and it would be costly. In Sweden the government is pressuring business to lower emissions, and IBM sells reduced-radiation terminals there that cost 10% to 15% more than comparable European models. At a minimum a company needs to be sensitive to the concerns of pregnant workers, perhaps agreeing to provide alternative jobs during pregnancy. CORPORATIONS should also be taking ergonomics seriously. Warns Marvin Dainoff, the director of the Center for Ergonomic Research at Ohio's Miami University: ''Office workers who work in fixed postures at a VDT are almost as much at risk for muscular disorders as construction workers.'' The optimal VDT environment includes lower light levels than in areas devoted to paperwork, partly to reduce glare on the screen, and maximum adjustability of furniture and lighting for the machine operator. He should be given brief rest breaks whenever he wants. One study found that merely allowing workers to take discretionary breaks, with no other improvements in the work environment, reduced musculo-skeletal complaints. Along with other companies, IBM is already taking action. The 175,000 IBM employees who work on VDTs can generally take a break whenever they choose. Since 1981 the company has offered special glasses to anyone who spends more than 20% of their time at a terminal. The glasses are designed to allow operators to focus on a VDT at a distance of about 20 inches. Normal reading glasses provide optimal acuity at about 14 inches. Education helps too. In 1986, IBM considered buying new ergonomic chairs for its entire work force but decided to save the $33 million expense and methodically teach people how to adjust the chairs they had. At the Los Angeles Times, employees can request special furniture and choose from different types of chairs. The company provides eye exams and special glasses, and an orthopedic surgeon visits the medical department periodically to advise employees about pains that may accompany VDT work. Observes James Trunzo, a New York architect who has built his practice around the design of automated offices: ''Management is scared because they think they've got to lob grenades into their spaces and start anew, but sometimes it takes no more than rearranging the furniture and removing a few light bulbs.'' Studies done by the Buffalo Organization for Social and Technological Innovation suggest it is possible to raise office productivity 2% to 7% by tweaking up the office environment. The group says such changes pay for themselves within five years. Some companies are going beyond ergonomics and taking VDT complaints as a cue for broader organizational change, such as the redesign of work. Aetna Life & Casualty in Hartford last year reorganized its payroll department to combine ten full-time data-entry jobs with ten jobs that involve paperwork and telephoning. Now nobody in the department spends more than 70% of his day on a VDT. Morale and productivity have gone up dramatically since the change, says Richard Assunto, Aetna's payroll services manager. If more isn't done to calm concerns about VDTs in the workplace, companies may have the matter taken out of their hands. In June Suffolk County in New York enacted the nation's first law governing the use of VDTs. It specifies particular kinds of furniture and lighting. Business groups are challenging the law in court. Most European governments already restrict workers to a maximum of four hours of VDT use per day. THROUGH the mounting clamor of the debate, two points come clear: First, we need to know more about VDT safety. Second, companies should be doing more to support the research effort. In the face of uncertainties like those surrounding the video display terminal, any prudent manager wants to gather as much information as he can -- to protect his employees and to sleep with a clear conscience. He wants to get ahead of the issue. On VDT safety, he still has an opportunity to do just that.