p-Tert-Butylphenol - UNEP Chemicals

OECD SIDS P-TERT-BUTYLPHENOL
Test substance: purity: 99.9%
Remarks: Author considered there was no systemic toxicity of this chemical but the
tolerable dose of this chemical would be around 250 mg/kg/day for OECD
Combined Repeat Dose and Reproductive/Developmental Toxicity
Screening Test, because of difficulty of breathing, probably causing by
irritation.
Reference: MHW, Japan: Unpublished
(b)
Species/strain: Rat/Crj:CD (SD)
Sex: Female [ ]; Male [ ]; Male/Female [ X ]; No data [ ]
Route of Administration: Oral (gavage)
Exposure period: Male: 44 days
Female: from 14 days before mating to day 4 of lactation
Frequency of treatment:
Post exposure observation period:
Dose: 0 (Vehicle), 20, 60, 200 mg/kg/day
Control group: Yes [X]; No [ ]; No data [ ]; 0.5% aqueous methyl cellulose
Concurrent no treatment [ ]; Concurrent vehicle [X]; Historical [ ]
NOAEL: 200 mg/kg/day as systemic toxicity
LOAEL:
Results: No treatment related changes were observed except noisy respiratory sound
in a few females of the 200 mg/kg. Only plasma albumin in the 200 mg/kg
males was decreased.
Method: OECD Combined Repeat Dose and Reproductive/Developmental Toxicity
Screening Test (OECD TG 422)
GLP: Yes [X] No [ ] ? [ ]
Remarks: Author considered the noisy respiratory sound was likely related to irritation
of the respiratory tract caused by the oral administration of the chemical.
Test substance: purity: 99.9%
Reference: MHW, Japan: 1996
(c)
Species/strain: Syrian Golden hamsters
Sex: Female [ ]; Male [X]; Male/Female [ ]; No data [ ]
Route of Administration: Oral (feed)
Exposure period: 20 weeks
Frequency of treatment: Daily
Post exposure observation period:
Dose: 15 g/kg diet (calculated daily dose as 120 g of body weight and 10 g/day of
food consumption: 1.25 g/kg b.w.)
Control group: Yes [X]; No [ ]; No data [ ]; basal diet
Concurrent no treatment [X]; Concurrent vehicle [ ]; Historical [ ]
NOAEL:
LOAEL: 1,250 mg/kg/day
Results: Body weights were decreased by 5 % and relative liver weights were
increased, compared to the control group. In histological examination,
grossly prominent thickening of the forestomach epithelium with a keratinlike
white substance was observed in the posterior and anterior walls along
the lesser curvature and adjacent to the esophagus. Hyperplasia observed in
the forestomach was classified into three types, mild (< 0.1 mm; 15/15 and
7/15 in treated and control group, respectively), moderate (0.1 - 0.5 mm;
12/15 and 1/15) and severe (> 0.5 mm; 11/15 and 0/15). Another category
of changes was papillomatous lesions (7/15 and 0/15), in which the
epithelium showed papillary upward projection with slight atypia of cells,
UNEP Publications 111