2-(4-tert-butylphenyl)-6-cyano-5-[bis(ethoxycarbonylmethyl)carbamoyloxy]-1H-pyrrolo[1,2-b][1,2,4] triazole-7-carboxylic acid 2,6-di-tert-butyl-4-methylcyclohexylester

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 January 2004 - 04 February 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, done to valid guidelines and the study was conducted under GLP conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: JMAFF, 12 Nousan, Notification No. 8147 (2000)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

448-050-6

EC Name:

-

Cas Number:

444065-11-6

Molecular formula:

C41 H57 N5 O8

IUPAC Name:

2,6-di-tert-butyl-4-methylcyclohexyl 5-{[bis(2-ethoxy-2-oxoethyl)carbamoyl]oxy}-2-(4-tert-butylphenyl)-6-cyano-1H-pyrrolo[1,2-b][1,2,4]triazole-7-carboxylate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): UC-141
- Substance type: White powder
- Analytical purity: 99.7 % by area %; 98.2 % by mass %, calculated as: (100 % - volatile matter) x HPLC area %
- Lot/batch No.: CE-203
- Expiration date of the lot/batch: 01 January 2005
- Stability under storage conditions: Stable
- Storage conditions of test material: At room temperature in the dark

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Strain: Wistar strain Crl:(Wl) BR (outbred, SPF-Quality).
- Age at study initiation: Young adult animals (approx. 10 weeks old) were selected.
- Weight at study initiation: Mean value for males on day 1 of the study was 347 g; mean value for females on day 1 of the study was 246 g. Body weight variation did not exceed ± 20 % of the sex mean.
- Housing: Individually housed in labelled Macrolon cages (type III, height 15 cm) containing purified sawdust as bedding material.
- Diet: Standard pelleted laboratory animal diet, ad libitum.
- Water: tap water, ad libitum.
- Acclimation period: At least 5 days before start of treatment under laboratory conditions.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0 °C (actual range 18.6 – 22.9 °C)
- Humidity (%): 30 – 70 % (actual range 38 – 80 %)
- Air changes (per hr): Approximately 15 air charges per hour.
- Photoperiod (hrs dark / hrs light): 12 hours of artificial fluorescent light and 12 hours of darkness per day.

Administration / exposure

Type of coverage:

occlusive

Vehicle:

propylene glycol

Details on dermal exposure:

TEST SITE
- Area of exposure: One day before exposure (day -1) an area of approximately 5 x 7 cm on the back of the animal was clipped.
- % coverage: 10 % of the total body surface (approximately 25 cm² for males and 18 cm² for females).
- Type of wrap if used: The formulation was held in contact with the skin with a dressing, consisting of a surgical gauze patch (Surgy 1D) successively covered with aluminium foil and a Coban elastic bandage. A piece of Micropore tape was additionally used for fixation of the bandages in females only.

REMOVAL OF TEST SUBSTANCE
- Washing: The dressing was removed and the skin cleaned of residual test material using water.
- Time after start of exposure: 24 hours.

PREPARATION OF SOLUTION
- The formulation (w/w) was prepared within 4 hours prior to dosing. Homogeneity was accomplished to a visually acceptable level. Adjustment was made for specific gravity of the vehicle, which was 1.036.

APPLICATION
- Volume applied: 10 mL/kg bw.

Duration of exposure:

A single application for 24 hours.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5 per sex per dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed for mortality/viability twice daily. Body weights were measured on Days 1 (pre-administration), 8 and 15.
- Observations of clinical signs were carried out at periodic intervals on the day of dosing (day 1) and once daily thereafter, until day 15. The time of onset, degree and duration were recorded and the symptoms graded according to fixed scales:
Maximum grade 4: grading slight (1) to very severe (4)
Maximum grade 3: grading slight (1) to severe (3)
Maximum grade 1: presence is scored (1).
- Necropsy of survivors performed: yes. At the end of the observation period (day 15), all animals were sacrificed by asphyxiation using an oxygen/carbon dioxide procedure and subjected to necropsy. Descriptions of all internal macroscopic abnormalities were recorded.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality occurred.

Clinical signs:

Hunched and flat posture, chromodacryorrhoea (snout) and ptosis were noted among the animals. The animals had recovered from the symptoms between days 3 and 7. Scales, scabs and erythema were seen on the treated skin area among the animals during the observation period.

Body weight:

The changes noted in body weight gain in males and females were within the range expected for rats used in this type of study and were therefore considered not indicative of toxicity.

Gross pathology:

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

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of the test, no death or signs of treatment-related toxicity occurred in five male and five female rats exposed to the test material at 2000 mg/kg bw. The LC50 was therefore determined to be greater than 2000 mg/kg bw.

Executive summary:

The acute toxicity of the test material was determined using Wistar strain rats in an acute dermal toxicity test performed under GLP conditions and in accordance with the standardised guidelines OECD 402, EU Method B.3, EPA OPPTS 870.1200 and JMAFF 12 Nousan, Notification No. 8147.

Ten rats (5 male and 5 female) were exposed to the test material in an occlusive fashion by dermal application at a limit dose of 2000 mg/kg bw in propylene glycol for 24 hours (dose volume 10 mL/kg bw). Animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice.

Under the conditions of the test, no death or signs of treatment related toxicity occurred in the rats. The LC50 was therefore determined to be greater than 2000 mg/kg bw.