Cj. Hardy et al., 28-DAY REPEATED-DOSE INHALATION EXPOSURE OF RATS TO DIETHYLENE GLYCOLMONOETHYL ETHER, Fundamental and applied toxicology, 38(2), 1997, pp. 143-147
This study was carried out to provide information on the effects of in
halation of diethylene glycol monoethyl ether, a substance used in ind
ustry which may be accidentally inhaled by man. Sprague-Dawley CD rats
were exposed by inhalation to a test atmosphere containing diethylene
glycol monoethyl ether in a nose-only exposure system for 6 hr a day,
5 days a week for 28 days. Mean exposure levels were 0.09, 0.27, and
1.1 mg/liter. At the two lowest exposure levels the test substance was
present entirely as vapor, but at the highest exposure level the test
atmosphere was approximately equally divided by mass into respirable
droplets (aerosol) and vapor. A comprehensive battery of toxicological
evaluations including food consumption, body weight, clinical signs,
hematology, and biochemistry revealed no evidence of a systemic effect
of exposure. Histopathological examination showed changes indicative
of mild nonspecific irritation in the upper respiratory tract of rats
exposed at the two highest exposure levels. These changes consisted of
foci of necrosis in the ventral cartilage of the larynx of rats expos
ed at 0.27 or 1.1 mg/liter and an increase in eosinophilic inclusions
in the olfactory epithelium of the nasal mucosa of rats exposed at 1.1
mg/liter. The no observed adverse effect level for systemic effects w
as 1.1 mg/liter and the no observed adverse effect level for signs ind
icative of mild nonspecific irritation of the upper respiratory tract
was 0.09 mg/liter. (C) 1997 Society of Toxicology.