[Federal Register Volume 59, Number 10 (Friday, January 14, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-910]


[[Page Unknown]]

[Federal Register: January 14, 1994]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES
 

National Toxicology Program; Availability of Technical Report on 
Toxicology and Carcinogenesis Studies of Furan

    The HHS' National Toxicology Program announces the availability of 
the NTP Technical Report on the toxicology and carcinogenesis studies 
of furan, used primarily as an intermediate in the synthesis and 
preparation of other organic compounds and also in the preparation of 
numerous polymeric compounds used for preparation of temperature-
resistant structural laminates. Copolymers of maleic acid and furan 
form complexes with alkaline earth ions and are used in metals, 
foodstuffs, and machine dishwashing products as alternatives to 
phosphorus- and nitrogen-containing detergents.
    Two-year toxicology and carcinogenesis studies were conducted by 
administering to both sexes of rats doses of 0, 2, 4, or 8 mg furan per 
kg body weight and 0, 8, or 15 mg/kg furan to both sexes of mice in 
corn oil by gavage 5 days per week for 2 years.
    Under the conditions of these 2-year gavage studies there was clear 
evidence of carcinogenic activity\1\ of furan in male and female F344/N 
rats based on increased incidences of cholangiocarcinoma and 
hepatocellular neoplasms of the liver and on increased incidences of 
mononuclear cell leukemia. There was clear evidence of carcinogenic 
activity of furan in male and female B6C3F1 mice based on increased 
incidences of hepatocellular neoplasms of the liver and benign 
pheochromocytomas of the adrenal gland.
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    \1\The NTP uses five categories of evidence of carcinogenic 
activity observed in each animal study: two categories for positive 
results (``clear evidence'' and ``some evidence''), one category for 
uncertain findings (``equivocal evidence''), one category for no 
observable effect (``no evidence''), and one category for studies 
that cannot be evaluated because of major flaws (``inadequate 
study'').
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    Nonneoplastic liver lesions associated with furan administration in 
rats and mice included biliary tract fibrosis, hyperplasia, 
inflammation, and proliferation, as well as hepatocellular cytomegaly, 
degeneration, hyperplasia, necrosis, and vacuolization. In rats, 
increased severity of nephropathy with an associated increased 
incidence of parathyroid hyperplasia was associated with exposure to 
furan.
    The study scientist for this bioassay is Dr. R. D. Irwin. Questions 
or comments about the Technical Report should be directed to Dr. Irwin 
at P.O. Box 12233, Research Triangle Park, NC 27709 or telephone (919) 
541-3340.
    Copies of Toxicology and Carcinogenesis Studies of Furan (CAS No. 
110-00-9) in F344/N Rats and B6C3F1 Mice (Gavage Studies) (TR-402) are 
available without charge from Central Data Management, NIEHS, MD AO-01, 
P.O. Box 12233, Research Triangle Park, NC 27709; telephone (919) 541-
3419.

    Dated: January 7, 1994.
Kenneth Olden,
Director, National Toxicology Program.
[FR Doc. 94-910 Filed 1-13-94; 8:45 am]
BILLING CODE 4140-01-M