(Z)-α-[[2-(tert-butoxy)-1,1-dimethyl-2-oxoethoxy]imino]-2-(tritylamino)thiazol-4-acetic acid

Endpoint summary

Description of key information

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight.

The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2000 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:

27 November 2017 to 13 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Specific details on test material used for the study:

Batch: 14TATT-S01025C
Purity: 100.1% w/w
Physical state I Appearance: White powder
Expiry Date: 24 December 2017
Storage Conditions: room temperature in the dark

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Female Wistar (RccHan™:WIST) strain rats were supplied by Envigo RMS (UK) Limited, Oxon, UK. On receipt the animals were randomly allocated to cages. The females were nulliparous and non-pregnant. After an acclimatization period of at least 5 days the animals were selected at random and given a number unique within the study by indelible ink-marking on the tail and a number written on a cage card. At the start of the study the animals were 8 to 12 weeks of age. The body weight variation did not exceed ±20% of the mean body weight of any previously dosed animals.

The animals were housed in groups of up to four in suspended solid-floor polypropylene cages furnished with woodflakes. With the exception of an overnight fast immediately before dosing and for approximately 3 to 4 hours after dosing, free access to mains drinking water and food (2014C Teklad Global Rodent diet supplied by Envigo RMS (UK) Limited, Oxon, UK) was allowed throughout the study. The diet, drinking water and bedding were routinely analyzed and were considered not to contain any contaminants that would reasonably be expected to affect the purpose or integrity of the study. The temperature and relative humidity were set to achieve limits of 19 to 25 °C and 30 to 70% respectively. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness. The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Route of administration:

oral: gavage

Vehicle:

arachis oil

Remarks:

arachis oil BP

Details on oral exposure:

VEHICLE
For the purpose of the study the test item was freshly prepared, as required, as a suspension in arachis oil BP. Arachis oil BP was used because the test item did not dissolve/suspend in distilled water. The test item was formulated within 2 hours of being applied to the test system. It is assumed that the formulation was stable for this duration.

Doses:

A total of five animals were therefore treated at a dose level of 2000 mg/kg in the study.
Concentration: 200 mg/mL
Dose Volume (mL/kg): 10
All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to the fasted body weight at the time of dosing. Treatment of animals was sequential. Sufficient time was allowed between each dose group to confirm the survival of the previously dosed animals.

No. of animals per sex per dose:

5 f/dose

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations were made 30 minutes, 1, 2, and 4 hours after dosing and then daily for up to 14 days. Individual body weights were recorded on Day O ( the day of dosing) and on Days 7 and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, necropsy

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths.

Clinical signs:

other: No signs of systemic toxicity were noted during the observation period.

Gross pathology:

No abnormalities were noted at necropsy.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System - Unclassified).

Executive summary:

Introduction

The study was performed to assess the acute oral toxicity of the test item in the Wistar strain rat.

Methods

Following a sighting test at a dose level of 2000 mg/kg, an additional four fasted female animals were given a single oral dose of test item, as a suspension in arachis oil BP, at a dose level of 2000 mg/kg body weight. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

Results

Mortality. There were no deaths.

Clinical Observations. There were no signs of systemic toxicity.

Body Weight. All animals showed expected gains in body weight.

Necropsy. No abnormalities were noted at necropsy.

Conclusion

The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System - Unclassified).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04 December 2017 to 19 December 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Limit test:

yes

Specific details on test material used for the study:

Batch: 14TATT-S01025C
Purity (Dry): 100.1%w/w
Physical state I Appearance: white powder
Expiry Date: 24 December 2017
Storage Conditions: room temperature in the dark over silica gel

Species:

rat

Strain:

Wistar

Sex:

male/female

Type of coverage:

semiocclusive

Vehicle:

arachis oil

Details on dermal exposure:

On the day before treatment the back and flanks of each animal were clipped free of hair. Using available information on the toxicity of the test item, a group of five male and five female rats was treated with the test item at a dose level of 2000 mg/kg. The appropriate amount of test item, moistened with arachis oil BP, was applied as evenly as possible to an area of shorn skin (approximately 10% of the total body surface area). A piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage. The animals were caged individually for the 24-Hour exposure period. Shortly after dosing the dressings were examined to ensure that they were securely in place. After the 24- Hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with arachis oil BP to remove any residual test item. The animals were returned to group housing for the remainder of the study period. The animals were observed for deaths or overt signs of toxicity 30 minutes, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days. After removal of the dressings and subsequently once daily for 14 days, the test sites were examined for evidence of primary irritation and scored according to the following scale:

No erythema 0
Very slight erythema (barely perceptible) 1
Well-defined erythema 2
Moderate to severe erythema 3
Severe erythema (beef redness) to slight eschar formation (injuries in depth) 4

Edema Formation
No edema 0
Very slight edema (barely perceptible) 1
Slight edema ( edges of area well-defined by definite raising) 2
Moderate edema (raised approximately 1 millimeter) 3
Severe edema (raised more than 1 millimeter and extending beyond the area of 4
exposure)

Any other skin reactions, if present were also recorded.

Individual body weights were recorded prior to application of the test item on Day O and on Days 7 and 14. At the end of the study the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Duration of exposure:

24-Hour

Doses:

2000 mg/kg

No. of animals per sex per dose:

5/sex/dose

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed for deaths or overt signs of toxicity 30 minutes, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days. Individual body weights were recorded prior to application of the test item on Day O and on Days 7 and 14.
- Necropsy of survivors performed: yes
- Other examinations performed: mortality, clinical signs, dermal irritation, body weight,necropsy

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

There were no deaths.

Clinical signs:

other: No signs of systemic toxicity were noted during the observation period.

Gross pathology:

No abnormalities were noted at necropsy.

Interpretation of results:

GHS criteria not met

Conclusions:

The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2000 mg/kg body weight. The test item does not meet the criteria for classification according to the Globally Harmonized System of Classification and Labelling of Chemicals

Executive summary:

Introduction

The study was performed to assess the acute dermal toxicity of the test item in the Wistar strain rat.

Methods

A group often animals (five males and five females) was given a single, 24 hour, semi-occluded dermal application of the test item to intact skin at a dose level of 2000 mg/kg

body weight. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

Results

Mortality. There were no deaths.

Clinical Observations. There were no signs of systemic toxicity.

Dermal Irritation. There were no signs of dermal irritation.

Body Weight. All animals showed expected gains in body weight.

Necropsy. No abnormalities were noted at necropsy.

Conclusion

The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2000 mg/kg body weight. The test item does not meet the criteria for classification according to the Globally Harmonized System of Classification and Labelling of Chemicals

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed