4,4'-(2-ethylhexane-1,1-diyl)diphenol

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May to October 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study according to OECD method without significant deviations

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-(2-ethylhexane-1,1-diyl)diphenol

EC Number:

680-046-1

Cas Number:

74462-02-5

Molecular formula:

C20H26O2

IUPAC Name:

4,4'-(2-ethylhexane-1,1-diyl)diphenol

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Name: 4,4’-(2-Ethylhexylidene)bisphenol
Alias: BisP-IOTD
Lot No.: 120601
Appearance: White powder
Content: 99.6%
Date of manufacture: June 2012
Expiration date: Mar. 2014

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

Species, Strains: Rat, Sprague-Dawley (Crl:CD(SD)), SPF
Producer & supplier: ORIENTBIO INC., Korea
Justification for species selection: Sprague-Dawley rats are commonly used in toxicity studies with a large historical control data base.
Sex, number, age and the body weight range (at receipt): 1st: Females, 7 rats, 7 weeks old, 174.4 to 184.2 g
2nd: Females, 7 rats, 7 weeks old, 166.8 to 179.5 g
Sex, number, age and the body weight range (on administration): Females, 12 rats, 8 weeks old, 180.1 to 198.9 g
Quarantine and acclimation 1st: Upon receipt, all animals were subjected to the clinical examination. Body weights were recorded using an electronic balance (CP3202S, Sartorius, Germany).
General health examinations were conducted by responsible personnel of quarantine on the last day of quarantine/acclimation. All animals were observed for general condition and clinical signs daily and body weights were recorded on Day 7 after receipt.
2nd: Upon receipt, all animals were subjected to the clinical examination. Body
weights were recorded using an electronic balance (CP3202S, Sartorius, Germany). General health examinations were conducted by responsible personnel of quarantine on the last day of quarantine/acclimation. All animals were observed for general condition and clinical signs daily and body weights were recorded on Day 7 after receipt. All animals were quarantined for 3 days, moved from the quarantine room to the animal room and acclimated for 4 days
Animal identification
During the acclimation period, a temporary identification number was marked on the tail using a red indelible pen. Each cage was attached a tag for the quarantine and acclimation periods. Following group assignment, the animals were uniquely identified by a blue indelible marking on the tail and a color-coded cage card was placed on each cage.
Group assignment 1st: Following quarantine and acclimation (group assignment), 6 healthy females were selected and randomly distributed into 2 groups (3 females/group). The mean body weights of groups were calculated to ensure limited differences for each group. Each group (Step 1: G1 and Step 2: G2) was given an animal ID (G1: 2101–2103 and G2: 2201–2203).
2nd: Following quarantine and acclimation (group assignment), 6 healthy females were selected and randomly distributed into 2 groups (3 females/group). The mean body weights of groups were calculated to ensure limited differences for each group. Each group (Step 3: G3 and Step 4: G4) was given an animal ID (G3: 2301–2303 and G4: 2401–2403).
Animal Husbandry
Quarantine room No. 2nd: A315
Animal room No. 1st: A323, 2nd: A322
Type & size of a cage: Stainless wire mesh cage, 260W×350D×210H (mm)
Number of animals per cage: One animal/cage (during the study)
Temperature: 21.0 to 23.5 °C
Relative humidity: 39.5 to 60.0%
Air change: 10 to15 clean, fresh, filtered air changes per hour
Lighting: 12 hour light / dark cycle (7 AM to 7 PM via automated timer)
Intensity of illumination: 150 – 300 Lux
Cage washing: Every two weeks; cages and feeders were washed in a cage washer and sterilized by an autoclave.
Feed
Type: Pelleted rodent chow (Teklad Certified Irradiated Global 18% Protein Rodent Diet 2918C) Lot No. 2918C-120212MA
Supplier: Harlan Laboratories, Inc., U.S.A.
Method of supply: The diet was placed in feeders and provided ad libitum.
Analysis of diet: Dietary analyses of all batches used for the study was provided by the supplier, Harlan Laboratories, Inc. The results were confirmed to meet the allowable standard of this facility.
Drinking Water
Type and method of water supply: Public tap water in Cheongju-si was filtered and irradiated by ultraviolet light and provided ad libitum.
Analysis of drinking water: Samples of drinking water are analyzed for specified microorganisms once a month and all environmental contaminants once a year by the Research Institute of Health & Environment, ChungBuk (184, Osong saengmyeong1 (il)_ro (676, Yeonje-ri) Gangoe-myeon, Cheongwon-gun, Chungcheongbuk-do, REPUBLIC OF KOREA) according to the Regulation of Quality Criteria for Potable Water and Test (Ministry of Environment Ordinance No. 439, Revision Dec. 30, 2011). The results were confirmed to meet the allowable standard of this facility.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

Individual doses were calculated based on the animals’ body weight recorded just prior to dosing at a dose volume of 10 mL/kg body weight. Animals were dosed once via gastric intubation with 3-mL disposable syringes fitted with intubation tubes. Animals were fasted overnight, approximately 16 hours prior to dosing. Drinking water was provided ad libitum. Feed was provided approximately 4 hours after dosing.

Doses:

Due to the low expected toxicity of the test substance and based on the information supplied by the sponsor, 2,000 mg/kg was selected as the starting dose for this study. The following sequential dosing steps were based on the mortality and clinical observations of animals three or eighteen days after the previous dose level. The following dosage regimen was selected in accordance with the guideline.
The experimental design is shown as follows:
Group Step Dose (mg/kg) Dose volume (mL/kg) Animals (ID No.) Deaths
G1 Step 1 2,000 10 3 (2101–2103) One animal
G2 Step 2 2,000 10 3 (2201–2203) Two animals
G3 Step 3 300 10 3 (2301–2303) None
G4 Step 4 300 10 3 (2401–2403) None

No. of animals per sex per dose:

see section on doses, 3 animals at 2000 mg/kg bw and 3 animals on 300 mg/kg bw

Control animals:

no

Details on study design:

The study designed followed the OECD protocol 423 with two experiments at starting dose of 2000 mg/kg bw and two further experiments at the dose of 300 mg/kg bw.

Statistics:

Statistical analysis was not performed. Mean scores and values are presented.

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - <= 2 000 mg/kg bw

Based on:

test mat.

Mortality:

The following mortalities were seen and the individual decision steps:
Group Step Dose (mg/kg) Dose volume (mL/kg) Animals (ID No.) Deaths
G1 Step 1 2,000 10 3 (2101–2103) One animal
G2 Step 2 2,000 10 3 (2201–2203) Two animals
G3 Step 3 300 10 3 (2301–2303) None
G4 Step 4 300 10 3 (2401–2403) None

Two animals at 2,000 mg/kg were found dead on Day 1 after dosing and one animal at 2,000 mg/kg was found dead on Day 2 after dosing. All animals at 300 mg/kg were survived the duration of the study.

Clinical signs:

Compound-colored stool, mucous stool and/or soiled perineal region were evident in three to six animals at 2,000 mg/kg from 30 minutes to 6 hours after dosing. Compound-colored stool, decrease in locomotor activity, decrease of fecal volume, irregular respiration, mucous stool and/or soiled perineal region were evident in one to four animals on Day 1 after dosing. Two animals were found dead with signs of compound-colored stool, lacrimation, soiled perineal region and/or prone position on Day 1 after dosing. Greenish stool, irregular respiration, mucous stool and/or soiled perineal region were evident in one to three animals on Day 2 after dosing. One animal were found dead with signs of soiled perineal region and prone position on Day 2 after dosing. Mucous stool, soiled perineal region, greenish stool and/or irregular respiration were evident in one to three animals from Day 3 to Day 7 after dosing. These animals returned to a normal appearance from Day 6 to Day 8 after dosing. Compound-colored stool and mucous stool were evident in four to six animals at 300 mg/kg from 2 to 6 hours after dosing. Compound-colored stool and mucous stool were evident in all animals on Day 1 after dosing. These animals returned to a normal appearance on Day 2 after dosing.

Body weight:

A tendency to suppress body weight gain and/or a decrease in body weight was evident in three surviving animals at 2,000 mg/kg on Day 1 and Day 3 after dosing. Then, these animals returned to normal on Day 7 after dosing. Normal body weight gains were evident in all animals at 300 mg/kg.

Gross pathology:

No grossly visible evidence of morphologic abnormalities was evident in any animals at 300 and 2,000 mg/kg.

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Following the acute class methodology the acute oral toxicity categroy 4 was assigned based on an LD50 value (rat) in the range of 300 - 2000 mg/kg bw.

Executive summary:

The purpose of this study was to assess the potential toxicity and to classify the test substance, 4,4’-(2-Ethylhexylidene)bisphenol, into the category according to GHS classification following a single oral administration to female Sprague-Dawley rats.

Three animals at 2,000 mg/kg were found dead on Days 1 and 2 after dosing. Compound-colored stool, mucous stool and/or soiled perineal region were evident at 2,000 mg/kg on the day of dosing. Compound-colored stool, decrease in locomotor activity, decrease of fecal volume, irregular respiration, mucous stool, soiled perineal region and/or greenish stool were evident from Day 1 to Day 7 after dosing. Three animals were found dead on Days 1 and 2 after dosing. These clinical signs were considered to be test substance-related effects. A tendency to suppress body weight gain and/or a decrease in body weight was evident in three surviving animals at 2,000 mg/kg on Days 1 and 3 after dosing. Then, these animals returned to normal on Day 7 after dosing. These clinical signs and body weight data were considered to be test substance-related effects. No test substance-related effects were evident at necropsy in any animals at 2,000 mg/kg. There were no deaths in any animals at 300 mg/kg. Compound-colored stool and mucous stool were evident at 300 mg/kg on the day of dosing and on Day 1 after dosing. These animals returned to a normal appearance on Day 2 after dosing. These clinical signs in animals at 300 mg/kg were considered to be test substance-related effects. No test substance-related effects were evident in body weight data and necropsy in any animals at 300 mg/kg.

Based on the results of the acute oral toxicity study in Sprague-Dawley rats, the test substance, 4,4’-(2-Ethylhexylidene)bisphenol, was classified to be Category 4 according to the GHS classification (consistent with CLP Regulation EC No 1272/2008).