Propan-2-yl-oxocyclobutane carboxylate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

13-11-2018 to 04-12-2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

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:

yes

Test material

Test material information

1

Reference substance name:

propan-2-yl 3-oxocyclobutane-1-carboxylate

EC Number:

834-970-9

Cas Number:

130111-95-4

Molecular formula:

C8H12O3

IUPAC Name:

propan-2-yl 3-oxocyclobutane-1-carboxylate

Test material form:

liquid

Details on test material:

Batch (Lot) Number: GR13224
Expiry date: 31 January 2020 (expiry date)
Physical Description: Colourless to pale yellow liquid
Purity/Composition: 99.6%
Storage Conditions: At room temperature

Test animals

Species:

rat

Strain:

Wistar

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 9-10 weeks old) were selected.
Weight at the Initiation of Dosing: 168 to 182 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 an ear mark and tail mark with
indelible ink.

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
according to body weights, with all animals within ± 20% of the sex mean. 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 21°C with an
actual daily mean relative humidity of 40 to 53%. 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:

unchanged (no vehicle)

Details on oral exposure:

A single dose of test item will be administered to the appropriate animals by oral gavage on
Day 1, using a syringe with a plastic gavage cannula attached. The starting dose level will be
2000 mg/kg body weight.
The dose volume for each animal will be based on the body weight measurement prior to
dosing. Dose volume (mL/kg body weight) will be calculated as follows:
Dose level (g/kg) / spec.gravity or density (g/mL).
The dosing formulations will be stirred continuously during dose administration.
Animals will be 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 will be available.

Doses:

2000 mg/kg bw (limit test)

No. of animals per sex per dose:

3 per sex pder dose

Control animals:

no

Details on study design:

Justification of Route and Dose Levels
The oral route is selected as it is a possible route of human exposure during manufacture,
handling or use of the test item.
The dose levels are based on the OECD test guidelines and will be 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 will be selected based on available toxicity data of the test item.

IN-LIFE PROCEDURES, OBSERVATIONS, AND MEASUREMENTS

Mortality/Moribundity Checks
Frequency: Twice daily throughout the study.
Procedure: Animals will be observed for general health/mortality
and moribundity. Animals will not be removed from
cage during observation, unless necessary for
identification or confirmation of possible findings.

Clinical Observations
Postdose Observations
Frequency: At periodic intervals on the day of dosing (at least three
times) and at least once daily thereafter. The observation
period will be 14 days.
Procedure: All the animals will be examined for reaction to dosing.
The onset, intensity and duration of these signs will be
recorded (if appropriate), particular attention being paid
to the animals during and for the first hour after dosing.

Body Weights
Frequency: On Days 1 (predose), 8 and 15.
Procedure: Animals will be individually weighed. A fasted weight
will be recorded on the day of dosing. Terminal body
weights will also be collected from animals if found
dead or euthanized moribund after Day 1.

TERMINAL PROCEDURES
All moribund animals and animals surviving to the end of the observation period will be
sacrificed by oxygen/carbon dioxide procedure. All animals assigned to the study are
subjected to necropsy and descriptions of all internal macroscopic abnormalities will be
recorded.

Statistics:

ANALYSIS
The oral LD50 value of the test item will be 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
will be established based on OECD guideline 423.
No statistical analysis will be performed (The method used is not intended to allow the
calculation of a precise LD50 value).
The results can be evaluated according to the Globally Harmonized System of Classification
and Labelling of Chemicals (GHS) of the United Nations (including all amendments) and the
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

Effect levels 1

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Effect levels 2

Sex:

female

Dose descriptor:

LD50 cut-off

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

other: Lethargy, hunched posture, uncoordinated movements and/or piloerection was noted for all animals on Days 1 and/or 2.

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 PF-06238566 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, PF-06238566 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 determine the potential toxicity of  PF-06238566, when

given by oral  gavage  at a single dose to rats of a single sex (females) at one or more defined

doses to evaluate the potential reversibility of any findings.

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.  

PF-06238566 was administered by oral  gavage  at a single dose 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.

Lethargy, hunched posture, uncoordinated movements and/or piloerection was noted for all

animals on Days 1 and/or 2.

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  PF-06238566 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,  PF-06238566 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).