WASHINGTON — The government issued warnings on Friday about two materials used daily by millions of Americans, saying that one causes cancerand the other might.
Government scientists listed formaldehyde as a carcinogen, and said it is found in worrisome quantities in plywood, particle board, mortuaries and hair salons. They also said that styrene, which is used in boats, bathtubs and in disposable foam plastic cups and plates, may cause cancer but is generally found in such low levels in consumer products that risks are low.
Frequent and intense exposures in manufacturing plants are far more worrisome than the intermittent contact that most consumers have, but government scientists said that consumers should still avoid contact with formaldehyde and styrene along with six other chemicals that were added Friday to the government’s official Report on Carcinogens. Its release was delayed for years because of intense lobbying from the chemical industry, which disputed its findings.
John Bucher, associate director of the National Toxicology Program, which produced the report, said evidence of formaldehyde’s carcinogenicity was far stronger than for styrene and that consumers were more likely to be exposed to potentially dangerous quantities of formaldehyde.
The federal Occupational Safety and Health Administration warned in April that a hair-care product, Brazilian Blowout Acai Professional Smoothing Solution, contained unacceptable levels of formaldehyde, and salon workers have reported headaches, nosebleeds, burning eyes, vomiting and asthmaattacks after using the product and other hair-straighteners.
Studies of workers like embalmers exposed to high levels of formaldehyde have found increased incidences of myeloid leukemia and rare cancers of the nasal passages and upper mouth.
Dr. Otis Brawley, chief medical officer at the American Cancer Society, said that formaldehyde is both worrisome and inescapable. “It’s the smell in new houses, and it’s in cosmetics like nail polish,” he said. “All a reasonable person can do is manage their exposure and decrease it to as little as possible. It’s everywhere.”
Consumers can reduce their exposure to formaldehyde by avoiding pressed-wood products or buying only those that are labeled as U.L.E.F. (ultra-low-emitting formaldehyde), N.A.F. (no added formaldehyde) or C.A.R.B. (California Air Resources Board) Phase 1 or Phase 2 compliant.
Styrene is mostly a concern for workers who build boats, car parts, bathtubs and shower stalls. Studies of workers exposed to high levels of styrene have found increased risks of leukemia and lymphoma and genetic damage to white blood cells. There is also some evidence that styrene increases the risks of cancer of the pancreas and esophagus among styrene workers, the report found. Consumers can be exposed to styrene from the fumes of building materials, photocopiers and tobacco smoke.
As for styrene’s presence in plastic utensils and other consumer products, Dr. Brawley likened the risk from such products to that of coffee and cellphones — uncertain and slight.
An industry spokesman said the action will hurt small businesses.
“It will unfairly scare workers, plant neighbors and could have a chilling effect on the development of new products,” said Tom Dobbins of the American Composites Manufacturers Association. “And our companies are primarily small businesses, and this could hurt jobs and local economies.”
Cal Dooley, president and chief executive of the American Chemistry Council, a trade association that represents companies that make and use polystyrene and formaldehyde, rejected the report’s conclusions. “We are extremely concerned that politics may have hijacked the scientific process,” he said.
Some in the industry have promised to continue fighting the report, and will appeal elements of its findings. But some manufacturers already have begun using alternatives to formaldehyde in their products.
This is the 12th cancer list released by the toxicology program at the National Institutes of Health, and each has been controversial. In 2000, controversy erupted over the ninth report’s listing of secondhand smoke and tanning beds. The 11th report’s listing in 2005 of naphthalene, which is used in mothballs, caused similar concern.
That this latest report would warn about formaldehyde and styrene has been suspected by industry since shortly after the release of the previous report, and industry groups have fought the process behind its release ever since. As a result, the government added numerous public comment periods to the process, and even after it was written, officials at the Department of Health and Human Services delayed the report’s release for months to cope with industry complaints.
“Industry held this report up for four years,” said Jennifer Sass, a senior scientist at the Natural Resources Defense Council. “They have tried to create the impression that there was real scientific uncertainty here, but there’s not.”
The report also lists aristolochic acids, found in plants and sometimes used in herbal medicines, as a known carcinogen and added to the list of probable carcinogens other substances like captafol (a fungicide no longer sold in the United States), finely spun glass wool fibers (used in insulation), cobalt-tungsten carbide (used in manufacturing), riddelliine (plants eaten by cattle, horses and sheep) and ortho-nitrotoluene (used in dyes).
Aristolochic acids are sometimes used in herbal medicines to treat conditions like arthritis and gout. In 2001, the Food and Drug Administration warned against the use of products containing aristolochic acids after seeing an increase in kidney disease among users. Products using the chemical are Rheumixx and BioSlim Doctor’s Natural Weight Loss System Slim Tone Formula.
Glass wool fibers are finely spun fibers of glass that form a mass resembling wool. They are commonly used for insulation or filtration, and people can be exposed to them when they install or remove insulation during home improvement projects. Animal studies have shown that glass wool fibers cause lung tumors, but there is little evidence from human studies of a risk.