At any given time, in most any workplace, at least a few people have a cough or itchy eyes. Maybe it's a headache or breathing trouble.
They're allergic to work, right? No, but close. Something about the place where they workâbe it car exhaust leaking in from a window, bacteria from mold or chemicals from the carpetâcould be making them ill or causing irritation that goes away shortly after they leave work.
The phenomenon is known as sick building syndrome. Symptoms include headache, itchy skin or eyes, dry cough, dizziness, nausea, chest tightness and fatigue.
"I would suggest it [affects] probably 30 percent of the buildings built since the 1960s," says Jack Rostron, a lawyer and professor at John Moores University's School of the Built Environment in Liverpool, England. The World Health Organization has provided a similar estimate.
In the United States, the problem came to light in the 1970s, when industry began sealing buildings tighter for energy efficiency, says Mark Mendell, an epidemiologist with Lawrence Berkeley National Laboratory. Research into workers' complaints of illness didn't point to any one cause, leading some observers to suspect the symptoms were psychosomatic.
The "usual suspects" were studied, such as light, noise, vibration and chemicals. But it was hard to draw any broad conclusions from one building or work force to the next, Mendell says.
Since then, SBS has been substantiated, though the possible culprits are many and solutions are often just best guesses, say Rostron and Mendell. Science hasn't nailed down all the causes of SBS, or how frequently a given cause, such as mold, makes people sick. One building could have a mixture of problems or different problems from one area to the next, causing a range of symptoms. Potential problems will vary based on a building's age, location (industrial area, humid climate), industry and how well its heating, ventilating and air conditioning systems are maintained.
J. David Odom, an indoor air quality expert who specializes in moisture and mold-related problems, says mold is a big troublemaker. "It appears to me, and I believe many others, that mold is by far the most common indoor air complaint of building owners," he says.
Common symptoms of mold problems include eye, nose and respiratory irritation, he says. And while you can sometimes see or smell mold, often it's hard to locate, he says.
Odom notes that grocers have a few extra reasons to carefully monitor moisture levels in their buildings. Refrigeration equipment and water sprays in the produce department may increase humidity levels and lead to condensation problems.
Chemical sources include glues, upholstery, carpet, cleaning agents, copy machines and composite wood products that emit volatile organic compounds, including formaldehyde. Motor vehicle exhaust and other fumes can enter the building from outside.
Biological sources of SBS include bacteria, viruses and molds. One indoor bacteria known to grow in standing water can lead to Legionnaires' disease, a type of pneumonia.
No matter the cause of SBS in a particular building, its occupants typically get sick by inhaling something. But identifying a cause of SBS is also hard because workers who complain of symptoms don't operate in a vacuum. Two people in the same department may say they get headaches only at work. One might be sensitive to chemical fumes in the carpet, while the other gets head-aches from job stress.
With so many variables, some building owners simply ignore the problem, Mendell says. And though it's difficult to prove in court that a building made you sick, a few workers have won personal injury settlements based on SBS.
(While SBS refers chiefly to symptoms that disappear upon leaving work, buildings also can be the source of longer-term health problems, referred to as "building-related illnesses." In this instance, the symptoms?including cough, fever, chills and muscle achesâcan be clinically defined and, unlike SBS, the cause of the illness is clear, according to the U.S. Environmental Protection Agency. Radon and asbestos are not included in SBS because they are known to cause serious illness).
Scientists and private firms agree on several ways building owners can avoid or mitigate problems that could cause building-related symptoms.
- Walk through the building and look for signs of leaks, mold and ventilation problems.
- Maintain heating, ventilation and air conditioning systems so that the rate of exchange of new air for old is, at minimum, up to today's building codes, no matter how old the building is. New codes have higher standards. Also keep filters, vents and other equipment clean.
- Maintain indoor temperature at proper levels. Typically, the comfort range is thought to be 72 to 76 degrees, but fewer people complain of SBS symptoms at the lower end of the range, Mendell says.
- Eliminate sources of standing water, which can create mold. Sources can include roof leaks, equipment leaks and stagnant water in a humidifier, duct or drain pan. Water-stained ceiling tiles should be replaced.
- It's also wise to measure carbon monoxide levels, particularly if the building is in a high-traffic or industrial area.
"There are lots of studies that show dampness or visible mold in buildings can be related to asthma," Mendell says, "but nobody knows what exactly in there is causing the problemâfungi, microbials, dust mites."
For more help go to www.epa.gov/iaq/iaqinfo.html, or contact private firms that test air quality and provide remediation services.Kelly Pate Dwyer is a freelance writer in Denver.
Natural Foods Merchandiser volume XXVII/number 4/p. 14, 16