The Clinton administration, under intense pressure from industry, has
set aside plans to list as a cancer-causing substance the fiber glass
insulation used in 90 percent of U.S. homes.
Four major manufacturers of fiber glass insulation have campaigned for
three years to prevent their product from being labeled a carcinogen by
the federal National Toxicology Program (NTP). Members of the NTP
concluded unanimously in 1990 that fiber glass "may reasonably be
anticipated to be a carcinogen" and were preparing to list fiber glass
that way in the SEVENTH ANNUAL (1992) REPORT ON CARCINOGENS, the NTP's
annual listing of cancer-causing substances. The ANNUAL REPORT is
mandated by Public Law 95-622 and represents a consensus of 10 federal
health agencies. The International Agency for Research on Cancer
(IARC), of the World Health Organization, listed fiber glass as a
"probable carcinogen" in 1987.
In June of this year Mr. Clinton's Secretary of Health and Human
Services (HHS), Donna Shalala, ordered a review of the National
Toxicology Program's decision to list fiber glass as a carcinogen, and
thus postponed publication of the SEVENTH ANNUAL REPORT. It is the
first time HHS has ever called for review of an NTP decision.
Shalala's decision was a direct response to pressure from the North
American Insulation Manufacturers Association (NAIMA). NAIMA hired
Washington, D.C. attorney Harrison Wellford, a former "Nader's Raider"
and member of the Clinton transition team who had worked with Shalala
in the Jimmy Carter White House in the late '70s.
On February 25 Wellford wrote a "Dear Donna" letter in which he
reminisced about their days together in the White House. Then he
complained about the process by which government scientists had
concluded that fiber glass causes cancer, and finally he threatened
that NAIMA might take legal action if the NTP listed fiber glass as a
probable carcinogen. NAIMA has four members: CertainTeed Corp.; Owens-
Corning Fiber Glass Corp.; Knauf Fiber Glass GMBH; and Schuller
International, Inc. (formerly Manville Co.).
Soon after Shalala received Wellford's letter, the National Toxicology
Program staff prepared a response, denying his request for a re-review
of fiber glass. But that letter was never sent.
In late May, representatives of NAIMA met with Donald A. Henderson,
deputy assistant secretary for health and science at HHS, where they
found a receptive ear.
At the same time, the industry organized a letter-writing campaign to
members of Congress by employees of fiber glass manufacturing plants.
On June 9 Shalala told Wellford she was granting the delay he had asked
for. Three weeks later, the industry filed a formal petition asking for
the delay. The industry challenged the criteria used by HHS and NTP in
determining what substances to list as carcinogens. The World Health
Organization uses the same criteria.
A week after the formal petition was filed, according to the WASHINGTON
POST, Donald Henderson told his staff he agreed with the industry
position that the decision on fiber glass should be put to a formal
vote of the NTP executive committee and that he wanted all the
appropriate review committees to reconsider their decisions. Henderson
is former Dean of the School of Public Health at Johns Hopkins
University and is famous for organizing the program that successfully
eradicated smallpox worldwide. Within HHS, he has become known for
playing a role similar to that played by Dan Quayle's Competitiveness
Council in the Bush administration (see RHWN #251)--an informal,
behind-the-scenes court-of-last-resort where industry can appeal to
modify policies and scientific conclusions that it does not like.
The carcinogenicity of fiber glass and other MMMFs [man-made mineral
fibers] has been the subject of scientific and medical research for
more than 20 years. In 1970, Dr. Mearl F. Stanton at the National
Cancer Institute announced that "it is certain that in the pleura of
the rat, fibrous glass of small diameter is a potent carcinogen." The
pleura is the outer casing of the lungs; cancer of the pleura in humans
is called mesothelioma and it is caused by asbestos fibers. Stanton
continued his research and showed that it was the size of the fibers
that caused them to be carcinogenic: when glass fibers are manufactured
as small as asbestos fibers, they cause cancers in laboratory animals,
as asbestos fibers do. Asbestos is a potent human carcinogen, which
will have killed an estimated 300,000 American workers by the end of
this century. The finding that fiber glass causes diseases similar
to asbestos was chilling news in the early 1970s, and an additional 20
years of research has not made the problem seem less serious. Workers
in fiber glass and mineral wool manufacturing plants are exposed to
numbers of fibers far lower than the numbers to which asbestos workers
were exposed, yet several industry-sponsored epidemiological studies in
the U.S., Canada, and Europe have reported statistically significant
elevations in respiratory disease, including lung cancers.[5,6,7,8]
The immediate concern is for the health of manufacturing workers, and
for the health of insulation installers who may have even more exposure
(and in poorly-ventilated, enclosed spaces) compared to manufacturing
workers. Homeowners who handle small quantities of fiber glass
insulation briefly are probably in substantially less danger, though
wearing a special mask capable of filtering out tiny fibers is always a
good idea when handling fiber glass, mineral wool or asbestos. A
longer-term concern is that all the billions of pounds of fiber glass
insulation now in buildings will eventually go somewhere after the
buildings deteriorate. Fiber glass--which only came into commercial use
in 1940--is a very persistent substance and can now be measured at low
levels on remote rural mountain tops, giving rise to a concern that
humans will eventually pollute the entire atmosphere with low levels of
persistent, dangerous and irritating fibers. Glass fibers buried in the
ground have been measured "leaking" into the air above the surface of
burial sites such as landfills.
But for the present the government is only concerned about fiber glass
as it affects worker health. A 1988 review of fiber glass studies by
the National Institute of Occupational Safety and Health (NIOSH)
concluded, "Published experimental evidence [from laboratory animals]
demonstrates that fibrous glass has the same potential for inducing
cancer as asbestos fibers of the same dimension. Recently published
epidemiological data [from studies of exposed humans] indicates that
there has been a risk of lung cancer in people employed in both the
rock or slag wool and glass wool sectors of the man-made mineral fiber
industry amounting to some 25% above normal 30 years after first
employment. Furthermore, it is likely that man-made mineral fiber may
have about the same carcinogenic potential as asbestos fibers of the
Since July, 1991, the U.S. Department of Labor has required certain
fiber glass products, including insulation, to carry a warning label
that says, "Possible cancer hazard by inhalation."
NAIMA has challenged research findings, based on the way laboratory
animals are exposed to MMMFs, such as fiber glass. When rats breathe
mineral fibers in the air, their nasal passages efficiently capture the
fibers and prevent them from entering the lungs. Because rats cannot
breathe through their mouths (the way many children do, and the way
workers exerting themselves on the job may do), fibers are injected
directly into the lungs of rats to test for an effect. Medical
researchers consider this appropriate, since humans breathing through
their mouths can draw airborne fibers deep into their lungs. NAIMA has
challenged this technique for exposing laboratory animals to MMMFs, and
is thus challenging some of the fundamental practices of science,
medicine and public health, internationally. It is this aspect of Donna
Shalala's final response to her friends at NAIMA that will be most
interesting, and most telling.
 Frank Swoboda, "U.S. Rethinks Calling Fiberglass Possible
Carcinogen," WASHINGTON POST September 10, 1993, pg. B-1. And see:
Melissa Levy, "U.S. To Review Research That Suggests Fiberglass
Insulation is Carcinogen," WALL STREET JOURNAL September 13, 1993, pg.
 The annual list of carcinogens is drawn up by an inter-agency
Working Group for the Annual Reports on Carcinogens, which includes
representatives from the Agency for Toxic Substances and Disease
Registry (ATSDR); the Centers for Disease Control (CDC); the National
Institute for Occupational Safety and Health (NIOSH); the Consumer
Product Safety Commission (CPSC); the U.S. Environmental Protection
Agency (EPA); the Food and Drug Administration (FDA); the National
Cancer Institute (NCI); the National Institute of Environmental Health
Sciences (NIEHS); the National Library of Medicine (NLM); and the
Occupational Safety and Health Administration (OSHA).
 The early history of research on fiber glass was reviewed by
Katherine and Peter Montague, "Fiber Glass," ENVIRONMENT Vol. 16
(September 1974), pgs. 6-9.
 Philip J. Landrigan, "Commentary: Environmental Disease--A
Preventable Epidemic," AMERICAN JOURNAL OF PUBLIC HEALTH Vol. 82 (July
1992), pg. 941.
 L. Simonato and others, "The International Agency for Research on
Cancer Historical Cohort of MMMF Production Workers in Seven European
Countries: Extension of the Follow-Up," ANNALS OF OCCUPATIONAL HYGIENE
Vol. 31, No. 4B (1987), pgs. 603-623.
 Philip E. Enterline and others, "Mortality Update of a Cohort of
U.S. Man-Made Mineral Fibre Workers," ANNALS OF OCCUPATIONAL HYGIENE
Vol. 31, No. 4B (1987), pgs. 625-656.
 Harry S. Shannon and others, "Mortality Experience of Ontario Glass
Fibre Workers--Extended Follow-Up," ANNALS OF OCCUPATIONAL HYGIENE Vol.
31, No. 4B (1987), pgs. 657-662.
 John R. Goldsmith, "Comparative Epidemiology of Men Exposed to
Asbestos and Man-Made Mineral Fibers," AMERICAN JOURNAL OF INDUSTRIAL
MEDICINE Vol. 10 (1986), pgs. 543-552.
Descriptor terms: donna shalala; bill clinton; fiber glass;
carcinogens; insulation; iarc; hhs; north american insulation
manufacturers association; harrison wellford; certainteed; owens-
corning fiber glass; knauf fiber glass; schuller international;
manville co; donald henderson; who; world health organization; dan
quayle; competitiveness council; man-made mineral fibers; asbestos;
mearl stanton; niosh; studies;