ethyl N,S-bis(4-oxo-4-(2,6,6-trimethylcyclohex-3-en-1-yl)butan-2-yl)cysteinate

Endpoint summary

Description of key information

The acute oral toxicity of Scentaurus Berry (GR-87 -0307) has been tested under the OECD guideline No. 423.

It has been concluded that the median lethal dose of Scentaurus Berry after single oral administration to female rats is:

LD50 (female rat): greater than 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.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 April 2018 to 24 April 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

conducted under GLP conditions

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2001

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Version / remarks:

2002

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

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: 156 to 180 g.

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

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 43 to 51%. 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.

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

The Test Item, GR-87-0307, was administered as received. The test item was stored in the refrigerator and was allowed to warm to room temperature for at least 30 minutes before dosing.
Adjustment was made for density of the test item. A factor of 1.11 was used to correct for the purity/composition of the test item.
Any residual volumes were discarded.

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.

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. Dose volume (mL/kg body weight) was calculated as follows:
Dose level (g/kg) / spec.gravity or density (g/mL).
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.

Doses:

2000 mg/kg

No. of animals per sex per dose:

2 groups of 3 females

Control animals:

no

Details on study design:

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:
Postdose Observations: Postdose 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 (predose), 8 and 15. A fasted weight was recorded on the day of dosing.
- Terminal procedures: All and 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.

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.

Statistics:

No statistical analysis was performed (The method used is not intended to allow the calculation of a precise LD50 value).

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Key result

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: Hunched posture, piloerection, salivation and/or uncoordinated movements were noted for the animals on Day 1.

Gross pathology:

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

Interpretation of results:

GHS criteria not met

Conclusions:

The oral LD50 value of GR-87-0307 in Wistar 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.

Executive summary:

The objective of this study was to determine the potential toxicity of GR-87-0307, when given by oral gavage at a single dose to rats of a single sex 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 ClassMethod"

·        EC No 440/2008, part B: "Acute Oral Toxicity, Acute Toxic ClassMethod"

·        EPA, OPPTS 870.1100 (2002), "Acute OralToxicity"

·        JMAFF Guidelines (2000), including the most recentrevisions.

GR-87-0307 was administered by oral gavage to two consecutive groups of three female Wistar 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, piloerection, salivation and/or uncoordinated movements were noted for the 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 GR-87-0307 in Wistar 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.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Additional information

The study was performed to assess the acute oral toxicity of the test material in the Wistar rats Crl: WI(Han) strain, in accordance with the GLP principles and following OECD guideline 423 (2001) and the EC No 440/2008, part B "Acute Oral Toxicity, Acute Toxic Class Method".

The tested substance was given by oral gavage to two consecutive groups of three female at 2000 mg/kg body weight.

No mortality or abnormalities were observed after treatment. Macroscopic examination of the animals at the end of the observation period did not reveal treatment-related gross changes.

Under the test conditions, the oral LD50 of the test substance is > 2000 mg/kg bw in rats. In accordance with OECD Guideline 423, the LD50 cut-off of the test substance may be considered to be > 5000 mg/kg bw by oral route in rats. Therefore it is not classified according to the Regulation (EC) N° 1272-2008 and according to the GHS.

Justification for classification or non-classification

The substance does not meet classification criteria under Regulation (EC) No 1272/2008 for acute toxicity: oral (LD50 > 2000 mg/kg)