EPA study: Air pollution often worse indoors than outdoors


WASHINGTON -- In a study that could help explain the 'sick building syndrome,' federal officials said Thursday testing has found indoor air in new buildings has levels of harmful chemicals 100 times greater than outdoor air.

The Environmental Protection Agency study, the first major U.S. assessment of indoor air pollution in public buildings, said chemical concentrations in new buildings were highest in the initial months after construction was completed and could remain elevated for up to six months.


Altogether, more than 500 chemicals were detected in the 10 buildings sampled in the five-year study, including four homes for the elderly, three office buildings, one hospital, one school and an institute for governmental studies.

The buildings studied were located in Washington; Worcester, Mass.; Cambridge, Mass.; Fairfax, Va.; Martinsburg, W.Va. and Research Triangle Park in North Carolina. Three of the buildings were newly constructed.


Among other chemicals, the study found elevated concentrations of benzene, a known cancer-causing agent in humans, and chloroform, trichlorethylene, carbon tetrachloride and p-dichlorobenzene -- all carcinogenic in animals.

The study focused on a class of chemicals known as volatile organic compounds because they are suspected of contributing to the 'sick building syndrome' -- widespread reports of headaches, eye and nose irritation, fatigue, nausea and other maladies by employees in particular buildings.

The study found volatile organic compounds are emitted by a wide range of materials commonly used or found in buildings, including industrial solvents and cleaners, carpet glue, linoleum tile, vinyl and rubber moldings, toilet air fresheners, particle-board partitions and telephone cable.

'Of the 500 chemicals identified, about half were found only once, suggesting the presence of many small sources rather than a few dominant ones,' the study said.

'Concentrations of individual aromatic and aliphatic compounds such as xylenes and decane were elevated over outdoor levels by factors of 100 in (one) new building studied,' it said.

While emphasizing that the study proved no link between volatile organic compounds and problem buildings, EPA officials said the report made it clear indoor air pollution was a major health concern.

'Air inside buildings is typically more polluted than outdoor air,' said Eileen Claussen, acting deputy assistant EPA administrator for air and radiation. 'Sometimes twice as polluted, sometimes five times more polluted, sometimes 100 times more polluted.'


'We believe indoor air pollution is a serious problem,' she said.

Other indicators of the problem, she said, were health studies showing that inhalation of microscopic house dust mites account for 200,000 hospital visits annually by asthmatics and that 3,500 non-smokers die of lung cancer each year because they are exposed to high levels of residual smoke particles from cigarettes.

EPA officials noted some Scandanavian countries have passed laws to address the problem. For example, Sweden requires all new schools to use only outdoor air for ventiliation for six months after construction.

However, Claussen said EPA officials believe it may be premature to propose similar regulations in the United States because not enough is known about the extent and nature of indoor air pollution.

One of the more publicized 'sick' buildings is EPA headquarters in Washington, where ventiliation systems are now under study for possible improvements following strenuous protests from agency employees about health problems. A health survey of EPA headquarters workers is also being conducted.

One nationwide survey found that 25 percent of American workers feel the quality of the air at their workplace affects their work adversely. ---

The buildings examined in the EPA study were identified as: a three-story office building in Research Triangle Park, N.C.; an eight-story office building in southwest Washington; a multi-story public school in northeast Washington; a five-story nursing home in northwest Washington; a nine-story home for elderly in northwest Washington; a VA hospital in Martinsburg, W.Va.; a nursing home in Martinsburg; an one-story office building in Fairfax, Va.; the Belfer Center at the John F. Kennedy School of Government, Cambridge, Mass.; and the St. Francis Home for Elderly, Worcester, Mass.


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