Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study performed per EPA TSCA 40 CFR 798.1175 under GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report date:
1990

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: EPA TSCA 40 CFR 798.1175
Deviations:
no
GLP compliance:
yes
Test type:
fixed dose procedure
Limit test:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
4-(α,α-dimethylbenzyl)phenol
EC Number:
209-968-0
EC Name:
4-(α,α-dimethylbenzyl)phenol
Cas Number:
599-64-4
Molecular formula:
C15H16O
IUPAC Name:
4-(2-phenylpropan-2-yl)phenol
Constituent 2
Reference substance name:
290-968-0
IUPAC Name:
290-968-0
Details on test material:
- Name of test material: para-Cumylphenol, (PCP, CAS #599-64-4)
- Physical state: solid
- Storage condition of test material: After mixing, the test material was transferred to five small, clear colorless glass vials with beige plastic caps. A separate vial will be used to prepare each dose level. All aliquots were stored at room temperature.
- Purity not stated.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Animals were purchased from a USDS approved supplier, Harlan Sprague-Dawley, Inc.
- Age at study initiation: young adult
- Weight at study initiation: 220 – 357 grams
- Fasting period before study: Food withheld overnight prior to dosing.
- Housing: Housed in groups of two in wire mesh suspension cages.

- Diet: Purina laboratory rodent chow, or other comparable diet, provided ad libitum.
- Water: Tap water ad libitum.
- Acclimation period: All animals were acclimated to the laboratory for at least four days before being used.


ENVIRONMENTAL CONDITIONS
- Photoperiod: The animals were maintained on a 12-hour light/12-hour dark cycle.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on oral exposure:
Young adult Sprague Dawley rats were administered the test material as a 25% w/v formulation in corn oil to five groups of male and female rats.
Doses:
5.0, 2.5, 1.25, and 0.625 g/kg
No. of animals per sex per dose:
Two male and two female young Sprague Dawley rats were used per dose group.
Control animals:
no
Details on study design:
Animals were observed several times on the dose day and at least twice daily for 14 days post-dose. Body weights were measured and a gross necropsy was performed on all animals.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
1.77 other: g/kg
Mortality:
At the 5.0 g/kg dose level, one male and two females died one day after treatment and the second male died day two post dose. At the 2.5 g/kg dose level, one female died one day post dose, one male died day 3 post dose, and the remaining male and female animals died by day 7 post dose. No deaths were recorded at 1.25 g/kg or lower.
Gross pathology:
Mottled liver and spleen, congested kidneys, distended stomach, darkened intestine filled with red fluid, bright red colored lungs, and blackened spleen were observed at the 5.0 g/kg dose level. Mottled liver and spleen, congested kidneys, distended stomach, reddened and transparent intestines were observed at the 2.5 g/kg dose level. No abnormal gross pathology was noted in animals of the 1.25 g/kg or 0.625 g/kg dose groups.
Other findings:
LD50 = 1.77 g/kg

Any other information on results incl. tables

One male and one female died day 1 post dose at the 1.25 g/kg dose level, however, data from this dose group was replaced with a second 1.25 g/kg dose level due to erroneous sacrificing on day 11 of surviving animals in the first group. Only data from the second dose group at 1.25 g/kg with observations to the completion of the observation period were used to calculate the LD50.

Applicant's summary and conclusion

Conclusions:
Under the conditions of this study, the acute oral LD50 of p-Cumylphenol exposure to rats was 1.77 g/kg.