6,6'-di-tert-butyl-4,4'-butylidenedi-m-cresol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

11 to 25 March 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed in accordance with OECD & EU test guidelines in compliance with GLP and reported with a valid GLP certificate.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Naugalube 531

IUPAC Name:

Naugalube 531

Constituent 2

Reference substance name:

125643-61-0

Cas Number:

125643-61-0

IUPAC Name:

125643-61-0

Test material form:

liquid: viscous

Details on test material:

Sponsor's identification: NAUGALUBE 531
Date received: 17 December 1996
Description: dark straw-coloured viscous liquid
Storage conditions: ambient temperature (< 25°C), stored under artificial light

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

Five male and five female Sprague-Dawley CD (Crl : CD BR) strain rats supplied by Charles River (UK) Ltd, Margate, Kent were used. At the start of the study the males weighed 208 to 229g, and the females 21 6 to 239g, and were approximately eight to twelve weeks old. After a minimum acclimatisation period of five 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.
The animals were housed in suspended polypropylene cages furnished with woodflakes. The animals were housed individually during the 24-hour exposure period and in groups of five, by sex, for the remainder of the study. Free access to mains drinking water and food (Rat and Mouse Expanded Diet No.1, Special Diets Services Limited, Witham, Essex, UK) was allowed throughout the study.
The animal room was maintained at a temperature of 19 to 22 °C and relative humidity of 47 to 53%. The rate of air exchange was approximately fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light and twelve hours darkness.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

On the day before treatment the back and flanks of each animal were clipped free of hair using veterinary clippers.
The calculated volume of the test material, as received, was applied uniformly to an area of shorn skin (approximating to 10% of the total body surface area) using a graduated syringe. A piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage. The bandage was further secured with a piece of BLEN DERM wrapped around each end. 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 distilled water to remove any residual test material. The animals were returned to group housing for the remainder of the study period.

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 males and 5 females used

Control animals:

not required

Details on study design:

The animals were observed for deaths or overt signs of toxicity ½, 1, 2 and 4 hours after dosing and subsequently once daily for fourteen days.
After removal of the dressings and subsequently once daily for fourteen days, the test sites were examined for evidence of primary irritation and scored according to the following scale from Draize J H (1 977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington DC
Any other skin reactions, if present were also recorded.
Individual bodyweights were recorded prior to application of the test material on Day 0 and on Days 7 and 14.
At the end of the study the animals were killed by cervical dislocation and subjected to gross pathological examination. 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.

Statistics:

Data evaluations included the relationship, if any, between the animal's exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, gross lesions, bodyweight changes, mortality and any other toxicological effects.
Using the mortality data obtained, an estimate of the acute dermal median lethal dose (LD50) of the test material was made.

Results and discussion

Effect levels

Sex:

male/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 study.

Gross pathology:

No abnormalities were noted at necropsy.

Other findings:

No signs of skin irritation were noted during the study.

Any other information on results incl. tables

TABLE 1: INDIVIDUAL CLINICAL OBSERVATIONS AND MORTALITY DATA

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period after Dosing (Days)
		½	1	2	3	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	1-0 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	1-1 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	1-2 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	1-3 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	1-4 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-1 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-2 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-3 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-4 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0 = no signs of systemic toxicity

 

TABLE 2: INDIVIDUAL DERMAL REACTIONS

Dose Level mg/kg	Animal Number and Sex	Observation	Effects Noted After Initiation of Exposure (Days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	1-0 Male	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	1-1 Male	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	1-2 Male	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	1-3 Male	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	1-4 Male	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	2-0 Female	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	2-1 Female	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	2-2 Female	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	2-3 Female	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0
	2-4 Female	Erythema Oedema Other	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0	0 0 0

0 = no signs of dermal irritation

 

TABLE 3: INDIVIDUAL BODYWEIGHTS AND WEEKLY BODYWEIGHT CHANGES

Dose Level mg/kg	Animal Number and Sex	Bodyweight (g) at Day			Bodyweight Gain (g) During Week
		0	7	14	1	2
2000	1-0 Male	229	275	328	46	53
	1-1 Male	215	238	259	23	21
	1-2 Male	208	254	296	46	42
	1-3 Male	218	261	305	43	44
	1-4 Male	222	271	319	49	48
	2-0 Female	222	233	245	11	12
	2-1 Female	219	231	243	12	12
	2-2 Female	216	236	241	20	5
	2-3 Female	239	256	271	17	15
	2-4 Female	223	223	235	2	10

 

TABLE 4: INDIVIDUAL NECROPSY FINDINGS

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	1-0 Male	Killed Day 14	No abnormalities detected
	1-1 Male	Killed Day 14	No abnormalities detected
	1-2 Male	Killed Day 14	No abnormalities detected
	1-3 Male	Killed Day 14	No abnormalities detected
	1-4 Male	Killed Day 14	No abnormalities detected
	2-0 Female	Killed Day 14	No abnormalities detected
	2-1 Female	Killed Day 14	No abnormalities detected
	2-2 Female	Killed Day 14	No abnormalities detected
	2-3 Female	Killed Day 14	No abnormalities detected
	2-4 Female	Killed Day 14	No abnormalities detected

 

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute dermal median lethal dose (LD50) of the test material, NAUGALUBE 531, in the Sprague-Dawley CD strain rat was found to be greater than 2000 mg/kg bodyweight. No symbol and risk phrase are required according to EU labelling regulations.

Executive summary:

A study was performed to assess the acute dermal toxicity of the test material in the Sprague-Dawley CD strain rat. The method used followed that described in the OECD Guidelines for Testing of Chemicals No. 402 "Acute Dermal Toxicity" (adopted 24 February 1987) and Method B3 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC). The study was performed in accordance with the Principles of Good Laboratory Practice (GLP) and reported with a valid GLP certificate.

 

The results may be used as a basis for classification and labelling under Annex VI of Council Directive 67/548/EEC (as adapted to technical progress by Commission Directive 93/21/EEC) relating to the classification, packaging and labelling of dangerous substances.

A group of ten animals (five males and five females) was given a single 24-hour, semi occluded dermal application to intact skin at a dose level of 2000 mg/kg bodyweight. The animals were observed for fourteen days after the day of treatment and were then killed for gross pathological examination.

 

There were no deaths. No signs of systemic toxicity were noted during the study. No signs of skin irritation were noted during the study.

 

All animals showed an expected gain in bodyweight during the study.

No abnormalities were noted at necropsy.

 

The acute dermal median lethal dose (LD50) of the test material in the Sprague-Dawley CD strain rat was found to be greater than 2000 mg/kg bodyweight. No symbol and risk phrase are required according to EU labelling regulations.