2,6-di-tert-butyl-4-nonylphenol

Endpoint summary

Description of key information

An in vivo skin irritation study in 3 New Zealand White rabbits according to OECD TG 404 with 0.5 mL undiluted test item for 4 hours semi-occlusive was irritating to rabbit skin.

An in vivo eye irritation study according to OECD TG 405 was initially performed in 1 New Zealand White rabbit with a single instillation of 0.1 mL undiluted test item in the conjunctival sac of the right eye. After consideration of the ocular responses in the first animal, two additional animals were treated. The test item did not produce positive criteria in any rabbit according to the EU labelling regulations. No symbol and risk phrase are therefore required.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was performed between 27 April 1995 and 4 May 1995.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted 17 July 1992

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Version / remarks:

of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 99/26.12.94

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature under nitrogen

FORM AS APPLIED IN THE TEST (if different from that of starting material): clear colourless liquid

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd., Moston, Sandbach, Cheshire, UK
- Age at study initiation: twelve to sixteen weeks old
- Weight at study initiation: 2.30 to 2.88 kg
- Housing: The animals were individually housed in suspended metal cages
- Diet (e.g. ad libitum): Free access to food (STANRAB SQC Rabbit Diet, Special Diets Services Ltd., Witham, Essex, UK) was allowed throughout the study.
- Water (e.g. ad libitum): Free access to mains drinking water was allowed throughout the study.
- Acclimation period: minimum acclimatisation period of five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 20 °C
- Humidity (%): 49 to 66%
- Air changes (per hr): approximately 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Remarks:

on the day before the test

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

4 hours

Observation period:

Up to 72 hours after exposure. An additional observation was made on day 7 to assess the reversibility of skin reactions.

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: dorsal flank area
- % coverage: 2.5 cm x 2.5 cm
- Type of wrap if used: A quantity of 0.5 mL of the test material was introduced under a 2.5 cm x 2.5 cm cotton gauze patch and placed in position on the shorn skin. The patch was secured in position with a strip of surgical adhesive tape (BLENDERM: approximate size 2.5 cm x 4.0 cm). To prevent the animals interfering with the patches, the trunk of each rabbit was wrapped in an elasticated corset (TUBIGRIP) and the animals were returned to their cages for the duration of the exposure period.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Four hours after application the corset and patches were removed from each animal and any residual test material removed by gentle swabbing with cotton wool soaked in 74% Industrial Methylated Spirits.
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
Approximately one hour following the removal of the patches, and 24, 48 and 72 hours later. An additional observation was made on day 7 to assess the reversibility of skin reactions.

SCORING SYSTEM:
- Method of calculation: according to the following scale from Draize J.H., (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington D.C. p.31.

-Erythea and Eschar Formation:
No erythema: 0
Very slight erythema (barely perceptible): 1
Well defined erythema: 2
Moderate to severe erythema: 3
Severe erythema (beef redness) to eschar formation (injuries in depth): 4
-Oedema Formation:
No oedema: 0
Very slight oedema (barely perceptible): 1
Slight oedema ( edges of area well defined by definite raising): 2
Moderate oedema (raised approximately 1 mm): 3
Severe erythema (raised more than 1 mm and extending beyond exposure area): 4
Any other skin reactions, if present, were also recorded.
An additional observation was made on day 7 to assess the reversibility of skin reactions.

Irritation parameter:

primary dermal irritation index (PDII)

Remarks:

total mean (12 values) divided by 6

Basis:

mean

Time point:

other: 24 and 72-hour readings

Score:

3.5

Max. score:

8

Reversibility:

other: Desquamation was noted at two treated skin sites and crust formation, considered to be reversible, at one treated skin site at the 7-day observation.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.3

Max. score:

4

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.7

Max. score:

4

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 72 h

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.7

Max. score:

4

Reversibility:

fully reversible within: 72 h

Irritant / corrosive response data:

Well-defined erythema was noted at all treated skin sites at the 1 and 24-hour observations with very slight to well-defined erythema at the 48 and 72-hour observations.
The reaction extended up to 4 cm bevond one treated skin site at the 24, 48 and 72-hour observations.
Very slight to slight oedema was noted at all treated skin sites at the 1-hour observation with very slight to moderate oedema at the 24 and 48-hour observations.
Slight oedema was noted at two treated skin sites at the 72-hour observation.
Desquamation was noted at two treated skin sites and crust formation, considered to be reversible, at one treated skin site at the 7-day observation.

Interpretation of results:

GHS criteria not met

Conclusions:

The test material, ISONOX 232, produced a primary irritation index of 3.5 and was classified as a MODERATE IRRITANT to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

Executive summary:

A study was performed to assess the irritancy potential of the test material to the skin of the New Zealand White rabbit. The method used followed the recommendations of the OECD Guidelines for Testing of Chemicals No. 404 "Acute Dermal Irritation/Corrosion" (adopted 17 July 1992) and Method B4 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

The results may be used as a basis for classification and labelling under Regulation No. 1272/2008 (CLP).

A single 4-hour, semi-occluded application of the test material to the intact skin of three rabbits produced well-defined erythema and very slight to slight oedema. Desquamation and crust formation were also noted.

The test material produced a primary irritation index of 3.5 and was classified as a moderate irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was performed between 1 May 1995 and 5 May 1995.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

adopted 24 February 1987

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Version / remarks:

Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 99/26.12.94

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature under nitrogen

FORM AS APPLIED IN THE TEST (if different from that of starting material): clear colourless liquid

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: supplied by David Percival Ltd., Moston, Sandbach, Cheshire, UK,
- Age at study initiation: twelve to sixteen weeks old
- Weight at study initiation: 2.88 to 3.42 kg
- Housing: The animals were individually housed in suspended metal cages
- Diet (e.g. ad libitum): Free access to food (STANRAB SQC Rabbit Diet, Special Diets Services ltd., Witham, Essex, UK) was allowed throughout the study.
- Water (e.g. ad libitum): Free access to mains drinking waterwas allowed throughout the study.
- Acclimation period: a minimum acclimatisation period of five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 22 °C
- Humidity (%): 58 to 66%.
- Air changes (per hr): approximately 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Vehicle:

unchanged (no vehicle)

Controls:

other: The left eye remained untreated and was used for control purposes

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): A volume of 0.1 mL of the test material was instilled into the conjunctival sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after instillation, to prevent loss of the test material, and then released.

Duration of treatment / exposure:

single treatment

Observation period (in vivo):

Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment.

Number of animals or in vitro replicates:

One rabbit was initially treated. After consideration of the ocular responses produced in the first treated animal, two additional animals were treated.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): No

SCORING SYSTEM: Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical evaluation given in Appendix I, (from Draize J.H. (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington D.C. p.48 to 49).

TOOL USED TO ASSESS SCORE: . Examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Remarks:

586 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #2

Remarks:

7 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #3

Remarks:

121 Female

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #1

Remarks:

586 Male

Time point:

24/48/72 h

Score:

0.3

Max. score:

3

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #2

Remarks:

7 Male

Time point:

24/48/72 h

Score:

0

Max. score:

3

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #3

Remarks:

121 Female

Time point:

24/48/72 h

Score:

0.3

Max. score:

3

Irritation parameter:

chemosis score

Basis:

animal #1

Remarks:

586 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #2

Remarks:

7 Male

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #3

Remarks:

121 Female

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

animal #1

Remarks:

586 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #2

Remarks:

7 Male

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #3

Remarks:

121 Female

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritant / corrosive response data:

Residual test material was noted around all treated eyes at the 1-hour observation. Dulling of the normal lustre of the corneal surface was noted in one treated eye at the 1-hour observation.
Iridial inflammation was noted in two treated eyes at the 1-hour observation.
Minimal to moderate conjunctival irritation was noted in all treated eyes at the 1-hour observation with minimal conjunctival irritation in two treated eyes at the 24-hour observation.
No ocular effects were noted in one treated eye at the 24-hour observation and the remaining treated eyes at the 48-hour observation.

Interpretation of results:

GHS criteria not met

Conclusions:

The test material, ISONOX 232, produced a maximum group mean score of 13.3 and was classified as a MINIMAL IRRITANT (CLASS 3 ON A 1 TO 8 SCALE) to the rabbit eye according to Regulation No. 1272/2008 (CLP). The test material did not produce positive criteria in any rabbit according to the EU labelling regulations. No symbol and risk phrase are therefore required.

Executive summary:

A study was performed to assess the irritancy potential of the test material to the eye of the New Zealand White rabbit. The method used followed that described in the OECD Guidelines for Testing of Chemicals No. 405 "Acute Eye Irritation/Corrosion" (adopted 24 February 1987) and Method B5 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

The results may be used as a basis for classification and labelling under Regulation No. 1272/2008 (CLP).

A single instillation of the test material to the non-irrigated eye of three rabbits produced iridial inflammation and minimal to moderate conjunctival irritation.

Dulling of the normal lustre of the corneal surface was also noted. No ocular effects were noted in one treated eye at the 24-hour observation and the remaining treated eyes at the 48-hour observation.

The test material produced a maximum group mean score of 13.3 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system. The test material did not meet the criteria for classification as irritant according to Regulation No. 1272/2008 (CLP).

No symbol and risk phrase are required.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A key in vivo study was performed to assess the irritancy potential of the registered substance to the skin of the New Zealand White rabbit (Snell, 1995). The method used followed the recommendations of the OECD Guidelines for Testing of Chemicals No. 404. A single 4-hour, semi-occluded application of the test material to the intact skin of three rabbits produced well-defined erythema and very slight to slight oedema. Desquamation and crust formation were also noted. The test material produced a primary irritation index of 3.5 and was classified as a moderate irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

A key study was performed to assess the irritancy potential of the test material to the eye of the New Zealand White rabbit (Snell, 1995). The method used followed that described in the OECD Guidelines for Testing of Chemicals No. 405. A single instillation of the test material to the non-irrigated eye of three rabbits produced iridial inflammation and minimal to moderate conjunctival irritation. Dulling of the normal lustre of the corneal surface was also noted. No ocular effects were noted in one treated eye at the 24-hour observation and the remaining treated eyes at the 48-hour observation. The test material produced a maximum group mean score of 13.3 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system. The test material did not meet the criteria for classification as irritant according to EU labelling regulations. No symbol and risk phrase are required.

Justification for classification or non-classification

No classification and labelling is needed for skin and eye irritation of 2,6-di-tert-butyl-4-nonylphenol according to Regulation No. 1272/2008 (CLP).