2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27 January 2020 - 21 April 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

December 2001

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

December 2002

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: EC No 440/2008, part B: "Acute Oral Toxicity, Acute Toxic Class Method"

Version / remarks:

May 2008

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: JMAFF Guidelines - Appendix to Director General Notification, No. 12-Nousan-8147

Version / remarks:

November 2000, including the most recent revisions

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate

EC Number:

278-051-5

EC Name:

2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate

Cas Number:

75005-95-7

Molecular formula:

C28H30O3

IUPAC Name:

2-ethylhexyl 2-{[1,1'-biphenyl]-4-carbonyl}benzoate

Test material form:

liquid

Details on test material:

Purity/Composition: 96.27%
Storage Conditions: At room temperature
Test Facility test item number: 210244/A
Test item handling: No specific handling conditions required
CAS number: 75005-95-7
EC Number: 278-051-5
Substance Name: 2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate

Specific details on test material used for the study:

Physical Description: Colourless to pale yellow liquid (determined by Charles River Den Bosch)
Purity/Composition: 96.27%
Storage Conditions: At room temperature
Purity/Composition correction factor: No correction factor required
Test item handling: No specific handling conditions required
Chemical name: 2-Ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate
CAS number: 75005-95-7
EC Number: 278-051-5
Molecular formula: C28H30O3
Molecular weight: 414.22


Specific gravity / density: 1.0894 g/cm3 at 20.0 °C (determined by Charles River Den Bosch)

Solubility in vehicle (Polyethylene glycol 400): Not indicated

Stability in vehicle (Polyethylene glycol 400):
Stability for at least 24 hours at room temperature normal laboratory light conditions, stability for at least 8 days in the refrigerator and stability of 0.5 mL samples for at least 3 weeks in the freezer (≤ -15°C) is confirmed over the concentration range 1 to
200 mg/mL (solutions)

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Species: Rat
Strain: Crl: WI(Han)
Condition: Outbred, SPF-Quality
Source: Charles River Deutschland, Sulzfeld, Germany
Number of Animals: 6 Females (nulliparous and non-pregnant). Each dose group consisted of 3 animals.
Age at the Initiation of Dosing: Young adult animals (approximately 8 weeks old) were selected.
Weight at the Initiation of Dosing: 177 to 200 g.

Justification for Test System and Number of Animals
The Wistar Han rat was chosen as the animal model for this study as recognized by international guidelines as a recommended test system. The test method and number of animals were based on the test guidelines.
The study plan was reviewed and agreed by the Animal Welfare Body of Charles River Laboratories Den Bosch B.V. within the framework of Appendix 1 of project license AVD2360020172866 approved by the Central Authority for Scientific Procedures on Animals (CCD) as required by the Dutch Act on Animal Experimentation (December 2014).

Animal Identification
At study assignment, each animal was identified using a subcutaneously implanted electronic identification chip.

Environmental Acclimation
The animals were allowed to acclimate to the Test Facility toxicology accommodation for at least 5 days before the commencement of dosing.

Selection, Assignment, Replacement, and Disposition of Animals
Animals were assigned to the study at the discretion of the coordinating biotechnician, with all animals within ± 20% of the sex mean body weights. Animals in poor health or at extremes of body weight range were not assigned to the study.
Before the initiation of dosing, a health inspection was performed, and any assigned animal considered unsuitable for use in the study were replaced by alternate animals obtained from the same shipment and maintained under the same environmental conditions.
The disposition of all animals was documented in the study records.

Husbandry
Housing
On arrival and following assignment to the study, animals were group housed (up to 3 animals of the same sex and same dosing group together) in polycarbonate cages (Makrolon MIV type; height 18 cm.) containing sterilized sawdust as bedding material (Lignocel S 8-15, JRS - J.Rettenmaier & Söhne GmbH + CO. KG, Rosenberg, Germany) equipped with water bottles. The room in which the animals were kept was documented in the study records.
Animals were separated during designated procedures/activities. Each cage was clearly labeled.

Environmental Conditions
Target temperatures of 18 to 24°C with a relative target humidity of 40 to 70% were maintained. The actual daily mean temperature during the study period was 20 to 21°C with an actual daily mean relative humidity of 48 to 54%. A 12 hour light/12 hour dark cycle was maintained. Ten or greater air changes per hour with 100% fresh air (no air recirculation) were maintained in the animal rooms.

Food
Pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany) was provided ad libitum throughout the study, except during designated procedures.
The feed was analyzed by the supplier for nutritional components and environmental contaminants. Results of the analysis were provided by the supplier and are on file at the Test Facility.
It is considered that there were no known contaminants in the feed that would interfere with the objectives of the study.

Water
Municipal tap-water was freely available to each animal via water bottles.
Periodic analysis of the water was performed, and results of these analyses are on file at the Test Facility.
It is considered that there were no known contaminants in the water that would interfere with the objectives of the study.

Animal Enrichment
For psychological/environmental enrichment, animals were provided with paper (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom), except when interrupted by study procedures/activities.

Veterinary Care
Veterinary care was available throughout the course of the study; however, no examinations or treatments were required.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Details on oral exposure:

Experimental Design
The toxicity of the test item was assessed by stepwise treatment of groups of 3 females. The absence or presence of mortality of animals dosed at one step determined the next step, based on the test procedure defined in the guidelines. The onset, duration and severity of the signs of toxicity were taken into account for determination of the time interval between the dose groups. The first group was treated at a dose level of 2000 mg/kg. Based on the results, one additional group was dosed at 2000 mg/kg.

Administration of Test item
A single dose of test item was administered to the appropriate animals by oral gavage on Day 1, using a syringe with a plastic gavage cannula attached.
The dose volume for each animal was based on the body weight measurement prior to dosing. A dose volume of 10 mL/kg body weight was used for each dose.
The dosing formulations were stirred continuously during dose administration.
Animals were deprived of food overnight (for a maximum of 20 hours) prior to dosing and until 3-4 hours after administration of the test item. Water was available.

Justification of Route and Dose Levels
The oral route was selected as it is a possible route of human exposure during manufacture, handling or use of the test item.
The dose levels were based on the OECD test guidelines and were selected from the series 5 (lowest dose level), 50, 300 and 2000 (highest dose level) mg/kg body weight. The starting dose level should be the one that is likely to produce mortality in at least some of the animals and was selected based on available toxicity data of the test item.

VEHICLE
Identification: Polyethylene glycol 400
Supplier: Merck, Darmstadt, Germany
Specific gravity: 1.125

Rationale for Vehicle
Trial preparations were performed to select the suitable vehicle and to establish a suitable formulation procedure. These trials were not performed as part of this study and these preparations were not used for dosing. Raw Data of these trials will be retained by the Test Facility.

Study Initiation Date: 27 Jan 2020
Initiation of Dosing: 04 Feb 2020
Completion of In-life: 26 Feb 2020
Experimental Start Date: 03 Feb 2020
Experimental Completion Date: 26 Feb 2020

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

6 females treated at 2000 mg/kg bw

Control animals:

yes

Remarks:

historical control

Details on study design:

In-life Procedures, Observations, and Measurements
Mortality/Moribundity Checks
Throughout the study, animals were observed for general health/mortality and moribundity twice daily, in the morning and at the end of the working day. Animals were not removed from cage during observation, unless necessary for identification or confirmation of possible findings.

Clinical Observations
Post-dose Observations
Post-dose observations were performed at periodic intervals on the day of dosing (at least three times) and once daily thereafter. The observation period was 14 days.
All the animals were examined for reaction to dosing. The onset, intensity and duration of these signs was recorded (if appropriate). Signs were graded for severity and the maximum grade was predefined at 3 or 4. Grades were coded as slight (grade 1), moderate (grade 2), severe (grade 3) and very severe (grade 4). For certain signs, only its presence (grade 1) or absence (grade 0) was scored.

Body Weights
Animals were weighed individually on Day 1 (pre-dose), 8 and 15. A fasted weight was recorded on the day of dosing.

Terminal Procedures
All animals were sacrificed by oxygen/carbon dioxide procedure at the end of the observation period. All animals assigned to the study were subjected to necropsy and descriptions of all internal macroscopic abnormalities were recorded.

Statistics:

ANALYSIS
All results presented in the tables of the report are calculated using values as per the raw data rounding procedure and may not be exactly reproduced from the individual data presented.
The oral LD50 value of the test item was ranked within the following ranges: 0-5, 5-50, 50-300 or 300-2000 mg/kg b.w. or as exceeding 2000 mg/kg b.w. The LD50 cut-off value was established based on OECD guideline 423. No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

The results were evaluated according to:
- Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2017) (including all amendments).
- Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of items and mixtures (including all amendments).

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

other: Hunched posture was noted for all animals between Days 1 and 3 and erected fur in all animals on Day 1.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The oral LD50 value of the test item in Wistar Han rats was established to exceed 2000 mg/kg body weight.
According to the OECD 423 test guideline, the LD50 cut-off value was considered to exceed 5000 mg/kg body weight.
Based on these results, the test item does not have to be classified and has no obligatory labelling requirement for acute oral toxicity according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2017) (including all amendments) and Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).

Executive summary:

The objective of this study was to assess the toxicity of the test item when administered in a single dose to female rats at one or more defined dosages. Furthermore, the results of the study allowed the test item to be ranked according to most classification systems, currently in use. This study should provide a rational basis for risk assessment in man.

The study was carried out in compliance with the guidelines described in:

•       OECD No.423 (2001) "Acute Oral Toxicity, Acute Toxic Class Method".

•       EC No 440/2008, part B: "Acute Oral Toxicity, Acute Toxic Class Method".

•       EPA, OPPTS 870.1100 (2002), "Acute Oral Toxicity".

•       JMAFF Guidelines (2000), including the most recent revisions.

The test item was administered by oral gavage to two consecutive groups of three female Wistar Han rats at 2000 mg/kg body weight. Animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice (Day 15).

No mortality occurred.

Hunched posture was noted for all animals between Days 1 and 3 and erected fur in all animals on Day 1.

The body weight gain shown by the animals over the study period was considered to be similar to that expected for normal untreated animals of the same age and strain.

No abnormalities were found at macroscopic post mortem examination of the animals.

The oral LD50 value of the test item in Wistar Han rats was established to exceed 2000 mg/kg body weight.

According to the OECD 423 test guideline, the LD50 cut-off value was considered to exceed 5000 mg/kg body weight.

Based on these results, the test item does not have to be classified and has no obligatory labelling requirement for acute oral toxicity according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2017) (including all amendments) and Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments).