Reaction products of ((5E)-5-ethylidenebicyclo[2.2.1]hept-2-ene and (5Z)-5-ethylidenebicyclo[2.2.1]hept-2-ene) and 2-methyl-1,3-butadiene, epoxidized

Endpoint summary

Description of key information

Skin irritation: non-irritating, eq. or sim. to OECD 404, 1979

Eye irritation: non-irritating, eq. or sim. to OECD 405, 1979

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:

1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Pre-GLP study following a method equivalent to a recognised OECD guideline. Deviations to recognised guideline are noted. Applicant evaluated and/or recalculated the individual and mean scoring, where necessary.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

Occlusive dressing smaller exposure area (2.5cm2), longer exposure period (24h) shorter observation period (48h)

Qualifier:

according to guideline

Guideline:

other: 16 CFR 1500.41

Version / remarks:

To identify dermal irritation potential as defined in 16 CFR 1500.3(c)(3)(4)

Deviations:

no

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Recognised animal supplier
- Age at study initiation: at least 8 weeks
- Weight at study initiation:
- Housing: housed 2/cage in suspended wire mesh cages (30" x 18" x 18")
- Diet: rabbit chow ad libitum
- Water: ad libitum
- Acclimation period: at least one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 21
- Humidity (%): not reported
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): not reported

Type of coverage:

occlusive

Preparation of test site:

other: clipped / abraded

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): neat (liquid)

Duration of treatment / exposure:

24 hours

Observation period:

72 hours

Number of animals:

1 males; 5 females (6 in total)

Details on study design:

TEST SITE
- Area of exposure: 2.5 cm2
- % coverage: Not reported. The fur was clipped from the backs and sides of the animals. The back to the left of the spinal column of all animals was abraded. The abrasions, extending the length of the exposure site, scratched the stratum corneum but did not reach the derma or produce bleeding. The back to the right of the spinal column remained intact.
- Type of wrap if used: Occlusive (gauze wrapped with imperivous material)

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Not reported
- Time after start of exposure: Not applicable.

SCORING SYSTEM: Draize-scoring system. The mean values (6 rabbits) for erythema/eschar and edema formation on intact and abraded skin at 24 and 72 hours (a total of 8 values) are added and divided by 4 to give the Primary lrritation score. By the criteria of this test, Primary lrritant means a substance which is not corrosive, but which results in an empirical score of 5 or more. References: 16 CFR 1500.41 and 16 CFR 1500.3.

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24/48/72 h

Score:

1.17

Max. score:

8

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24/48/72 h

Score:

0.833

Max. score:

4

Reversibility:

other: Full reversibilty was observed within 72 hours within 3/6 rabbits

Remarks on result:

other: Time points 24 and 72hours are used in intact skin

Remarks:

USA Federal Hazardous Substances Act tests to 16 CFR 1500.3 terminate observations at 72hours.USA Federal Hazardous Substances Act tests to 16 CFR 1500.3 terminate observations at 72hours.

Irritation parameter:

edema score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24/48/72 h

Score:

0.34

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Remarks on result:

other: Time points 24 and 72hours are used in intact skin

Remarks:

USA Federal Hazardous Substances Act tests to 16 CFR 1500.3 terminate observations at 72hours.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24 h

Score:

1

Max. score:

4

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24 h

Score:

2

Max. score:

4

Remarks on result:

probability of mild irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #5

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

24 h

Score:

1

Max. score:

4

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

72 h

Score:

1

Max. score:

4

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

72 h

Score:

1

Max. score:

4

Remarks on result:

probability of mild irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #5

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

72 h

Score:

1

Max. score:

4

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

no indication of irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

no indication of irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #5

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #1

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

edema score

Basis:

animal #2

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

no indication of irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #3

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

no indication of irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #4

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #5

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritation parameter:

edema score

Basis:

animal #6

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Remarks:

intact skin

Irritant / corrosive response data:

Very slight to well defined erythema was noted during the observation period. Scores decreased from 24 to 72 hours.
Very slight to slight edema was noted at 24 hours. All 72 hour edema scores were zero.

Table 1. Skin reactions (using Draize scoring method)

Erythema & Eschar Formation	Hours	Rabbit number						Mean score
		1	2	3	4	5	6
Intact skin	24	1	1	1	2	1	1	1.17
	72	0	1	0	1	0	1	0.50
Abraded skin	24	1	1	1	2	1	1	1.17
	72	0	1	0	0	0	0	0.33
Edema
Intact skin	24	1	0	0	1	1	1	0.67
	72	0	0	0	0	0	0	0.00
Abraded skin	24	1	0	0	1	1	2	0.83
	72	0	0	0	0	0	0	0.00
Sum of mean scores								4.67
Primary irritation index = sum of mean scores/4								1.17

Interpretation of results:

GHS criteria not met

Remarks:

EU criteria not met

Conclusions:

Under the conditions of this study the test substance is not considered to be irritating to the skin of New Zealand white rabbits.

Executive summary:

The pre-GLP study was completed under 16 CFR 1500.41 following a guideline similar to OECD 404, to assess the irritancy potential of the test material to the skin of the New Zealand White rabbit. The test substance was evaluated in 6 New Zealand white rabbits. A dose of 0.5 ml test substance was applied to intact and abraded clipped dorsal skin site under a occlusive dressing for 24 hours. Skin observations were made 24 and 72 hours after patch removal. Very slight to well defined erythema was noted during the observation period. Scores decreased from 24 to 72 hours. Very slight to slight edema was noted at 24 hours. All 72 hour edema scores were zero. The test material produced a mean primary irritation index (PII) of 1.17 and is considered to be non-irritating to skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not 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:

1979

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Pre-GLP study following a method equivalent to a recognised guideline.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: 16 CFR 1500.42

Version / remarks:

To identify ocular irritation potential as defined in 16 CFR 1500.3(4)

Deviations:

no

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Recognised animal supplier
- Age at study initiation: 8 weeks
- Weight at study initiation: not reported
- Housing: housed 2/cage in suspended wire mesh cages {30" x 18" x 18"}.
- Diet: Rabbit chow ad libitum
- Water: ad libitum
- Acclimation period: at least 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 21
- Humidity (%):not reported
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): not reported

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL

Duration of treatment / exposure:

3 days

Observation period (in vivo):

3 days

Number of animals or in vitro replicates:

6 males

Details on study design:

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

SCORING SYSTEM: Draize scoring system. Reference 16 CFR 1500.42.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

48 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

48 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24 h

Score:

0.833

Max. score:

3

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

48 h

Score:

0

Max. score:

3

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

72 h

Score:

0

Max. score:

3

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

24 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

48 h

Score:

0.17

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(n=6) rabbits

Time point:

72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible within: 72h

Remarks on result:

probability of weak irritation

Irritant / corrosive response data:

No positive corneal scores were noted. No positive iridal scores. No positive conjunctival scores. Very slight irritation (redness and chemosis; max score 1) fully reversed within 72 hours.

Other effects:

- Lesions and clinical observations: None reported.
- Ophthalmoscopic findings: None reported.
- Histopathological findings: None reported.
- Effects of rinsing or washing: Not applicable.
- Other observations: None reported.

Interpretation of results:

GHS criteria not met

Remarks:

EU criteria not met

Conclusions:

Under the conditions of this study the test substance cannot be considered as an eye irritant.

Executive summary:

The pre-GLP study was completed under 16 CFR 1500.42 following a guideline similar to OECD 405, to assess the irritancy potential of the test material to the eye following a single application in the New Zealand White rabbit. A volume of 0.1 ml of the test material was placed into the conjunctival sac of one eye of 6 animals. The other eye remained untreated and was used for control purposes. Assessment of ocular damage/irritation was made approximately 24, 48 and 72 hours following treatment. No corneal opacity or iridal irritation was observed on any day. Very slight irritation redness and chemosis; max score 1; fully reversed within 72 hours. Based on the applicants recalculation of the mean scores the test material is not considered to be irritating to the eye under Regulation (EC) 1272/2008 criteria due to a complete absence of Corenal Opacity and Corneal Iritis indicative of full reversibility within 21-days. Redness and Chemosis scores were minor and fully reversed within 72 hours. There was additionally an absence of significant variation of responses.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation:

Eq. or similar to OECD TG 404, 1979: The pre-GLP study was completed under 16 CFR 1500.41 following a guideline similar to OECD 404, to assess the irritancy potential of the test material to the skin of the New Zealand White rabbit. The test substance was evaluated in 6 New Zealand white rabbits. A dose of 0.5 ml test substance was applied to intact and abraded clipped dorsal skin site under a occlusive dressing for 24 hours. Skin observations were made 24 and 72 hours after patch removal. Very slight to well defined erythema was noted during the observation period. Scores decreased from 24 to 72 hours. Very slight to slight edema was noted at 24 hours. All 72 hour edema scores were zero. The test material produced a mean primary irritation index (PII) of 1.17 and is considered to be non-irritating to skin.

Eq. or similar to OECD TG 402, 1979: The pre-GLP study was performed following a method similar to OECD 402 to assess the dermal toxicity of the test substance to the New Zealand white rabbit. The test substance was evaluated in ten female rabbits. A dose of 2000 mg/kg test substance (undiluted), was applied to the back clipped intact and abraded skin sites of the rabbit under a occlusive dressing for 24 hours. After twenty-four hours and any excess material was removed and the approximate amount remaining was noted. The animals were observed for a 14 day period for signs of toxicity and for mortalities. There were three mortalities during the study. In the intact skin sites on mortality occurred at day 13 with pre-mortality clinical signs including lethargy, diarrhoea, ptosis, adipsia and anorexia. In the abraded sites, two mortalities occurred. There were no pre-mortality clinical signs for day 6 mortality. For the day 13 mortality lethargy, ptosis, diarrhoea, yellow nasal discharge and emaciation, was observed. In the intact sites three of four survivors gained weight during the study. In number 7 survivor there was a slight body weight decline (- 0.1 g) at day 14. In the abraded sites, in number 6 there was a slight body weight decline (- 0.1 g) at day 14. In number 8 survivor there was no weight gain. Isolated instances of diarrhoea, lethargy and ptosis were noted in four survivors although remained generally healthy throughout the observation period. Local effects were very slight to well defined erythema and very slight to moderate oedema. Under the conditions of this study the LD50 was determined to be greater than 2000 mg/kg via the dermal route in the female rabbit. Applicant assessment indicates: there was evidence within the study that abrasion relatively increased mortality and/or led to more significant local reactions (reported on day 1) as compared to intact skin. Abrasion is to be avoided within OECD TG 402 as it increases dermal permeability. Additionally, OECD TG 405 utilises semi-occlusive application rather than the occlusive dressing utilised in the study. There is evidence within the study to indicate that the test item does not cause sufficient local effects that meet the GHS Skin Irritation: Category 2 criteria.

Within OECD TG 404, 1979: The mean score at 24 and 72h of intact skin was < 2.3 in all organisms in all response criteria (erythma/escar or odema) but effects persisted to the end of the observation period (72h). Since four or more organisms did not demonstrate a mean score greater than or equal to 2.3; there was an absence of reported significant dermal effects (e.g. alopecia, hyperplasia or scaling) and/or significant variability of responses, the substance is not considered to be irritating. The substance is not irritating to the skin. Further testing for skin irritation is unjustified.

Eye irritation/corrosion:

Eq. or similar to OECD TG 405, 1979: The pre-GLP study was completed under 16 CFR 1500.42 following a guideline similar to OECD 405, to assess the irritancy potential of the test material to the eye following a single application in the New Zealand White rabbit. A volume of 0.1 ml of the test material was placed into the conjunctival sac of one eye of 6 animals. The other eye remained untreated and was used for control purposes. Assessment of ocular damage/irritation was made approximately 24, 48 and 72 hours following treatment. No corneal opacity or iridal irritation was observed on any day. Very slight irritation redness and chemosis; max score 1; fully reversed within 72 hours. Based on the applicants recalculation of the mean scores the test material is not considered to be irritating to the eye under Regulation (EC) 1272/2008 criteria due to a complete absence of Corenal Opacity and Corneal Iritis indicative of full reversibility within 21-days. Redness and Chemosis scores were minor and fully reversed within 72 hours. There was additionally an absence of significant variation of responses.

Justification for classification or non-classification

The substance does not meet classification criteria under Regulation (EC) No 1272/2008 for dermal irritation.

 

The substance does not meet classification criteria under Regulation (EC) No 1272/2008 for eye irritation.

 

For skin irritation, the weight of evidence indicates that the substance has the potential to be slightly irritating however this is not sufficient for classification purposes. Available data indicates negative irritation in an in vivo dermal irritation study and within an in vivo acute dermal toxicity study. The irritation study utilised occlusive dressings (increases percutaneous absorption; potential altering of epidermal lipids, DNA synthesis, epidermal turnover, pH, epidermal morphology) resulting in a predisposition towards positive and irreversible irritation. The acute dermal toxicity study indicated a similar conclusion for intact skin under occlusive dressing day 1 observations, that would have been inadequate for GHS Skin Irritation Category 2 classification. Abrasion was demonstrated to enhance local effects (particularly oedema) and these observations were discarded in assessment. Since the methodology (abraded/occlusive) was not consistent with the modern OECD guidelines. The overall evidence by expert judgement indicates that the substance may produce transient slight irritation by the dermal route which is not sufficient for classification in accordance with the above criteria.

 

For eye irritation, the weight of evidence indicates that the substance has the potential to cause transient mild irritating effects to the eye but which are insufficient for classification based on the applicants recalculation of the mean scoring and evaluation of the results in six organisms demonstrating that the EU criteria had not been met. Effects in vivo on corneal opacity and iritis are non-existent and conjunctival effects are very low which fully reversed within 72 hours; the overall evidence is indicative of transient and reversible effects on the eye.

 

References:

1. ECHA Guidance on Application on the CLP Criteria, section 3.2 (v5.0, July 2017)

2. ECHA Guidance on Information Requirements and Chemical Safety Assessment (Chapter R.7a: Endpoint Specific Guidance, R.7.2.2, v6.0 July 2017)