[Federal Register Volume 59, Number 137 (Tuesday, July 19, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-17449]


[[Page Unknown]]

[Federal Register: July 19, 1994]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES
 

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

    The HHS' National Toxicology Program announces the availability of 
the MTP Technical Report on the toxicology and carcinogenesis studies 
of benzyl acetate, which is used as a flavoring agent in foods, as a 
fragrance in soaps and perfumes, as a solvent for cellulose acetate and 
nitrate, and as a component of printing inks and varnish removers. The 
NTP previously studied the toxicology and carcinogenicity of this 
chemical in F344/N rats and B6C3F1 mice using the gavage route of 
administration and corn oil as a vehicle. Benzyl acetate increased the 
incidences of pancreatic acinar cell adenomas in male rats and the 
incidences of hepatocellular adenomas and forestomach neoplasms in male 
and female mice. Because of the confounding effect of corn oil on the 
incidences of pancreatic neoplasms and because of controversy over the 
use of the gavage route of administration, the NTP decided to restudy 
benzyl acetate using the dosed feed route of administration.
    Toxicology and carcinogenesis studies were conducted by feeding 
groups of 60 male and female F344/N rats diets containing 0, 3,000, 
6,000, or 12,000 ppm benzyl acetate and groups of 60 male and female 
B6C3F1 mice diets containing 0, 330, 1,000, or 3,000 ppm benzyl 
acetate for 2 years.
    Under the conditions of these 2-year feed studies, there was no 
evidence of carcinogenic activity* of benzyl acetate in male or female 
F344/N rats receiving 3,000, 6,000, or 12,000 ppm; however, rats may 
have tolerated higher doses. There was no evidence of carcinogenic 
activity of benzyl acetate in male or female B6C3F1 mice receiving 
330, 1,000, or 3,000 ppm.
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    *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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    Nasal lesions associated with benzyl acetate exposure in male and 
female mice included nasal mucosa atrophy and degeneration (primarily 
of the olfactory epithelium), cystic hyperplasia of the nasal 
submucosal gland, and luminal exudate and pigmentation of the nasal 
mucosal epithelium.
    In premius 2-year gavage studies, benyzl acetate increased the 
incidence of acinar cell adenomas of the exocrine pancreas in male 
F344/N rats; the gavage vehicle may have been a contributing factor. 
There was no evidence of carcinogenic activity in female F344/N rats 
receiving 250 or 550 mg/kg a day.
    There was some evidence of carcinogenic activity in male and female 
B6C3F1 mice, indicated by the increased incidences of 
hepatocellular adenomas and squamous cell neoplasms of the forestomach.
    Questions or comments about the Technical Report should be directed 
to Central Data Management at P.O. Box 12233, Research Triangle Park, 
NC 27709 or telephone (919) 541-3419.
    Copies of Toxicology and Carcinogenesis Studies of Benzyl Acetate 
(CAS No. 140-11 1) in F344/N Rats and B6C3F1 Mice (Feed Studies) 
(TR-431) are available without charge from Central Data Management, 
NIEHS, MD A0-01, P.O. Box 12233, Research Triangle Park, NC 27709; 
telephone (919) 541-3419.

Kenneth Olden,
Director, National Toxicology Program.
[FR Doc. 94-17449 Filed 7-18-94; 8:45 am]
BILLING CODE 4140-01-M