Cyclohexanepropanol, 2,2,3,6-tetramethyl-.alpha.-propyl-

Endpoint summary

Description of key information

Skin irritation, in vivo: not irritating (may cause mild transient irritation), OECD TG 404, 2007

Eye irritation, in vivo: not eye irritating, OECD TG 405, 2007

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin corrosion: in vitro / ex vivo

Data waiving:

other justification

Justification for data waiving:

an in vitro skin irritation study does not need to be conducted because adequate data from an in vivo skin irritation study are available

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
In accordance with REACH Regulation (EC) No. 1907/2006 Annex VII, column 2 section 8.1.1 (as amended by Commission Regulation (EU) 2016/863) the in vitro skin corrosion (OECD TG 431) study does not need to be conducted based on the available information allowing a definitive conclusion on the classification of the substance. An available in vivo (OECD TG 404) skin irritation study is available and data in other endpoints (such as skin sensitisation and/or acute dermal toxicity) indicates that the substance is not skin corrosive and a definitive conclusion on the classification can be made. Furthermore, in accordance with section 1.2 of REACH Regulation (EC) No. 1907/2006 Annex XI the weight of evidence indicates that the substance is not skin corrosive and therefore in vitro testing may be omitted. According to ECHA Guidance on Information Requirements and Chemical Safety Assessment (Chapter R.7a: Endpoint Specific Guidance, R.7.2, July 2017) the study does not need to be conducted.

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27-03-2007 to 03-04-2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP. All relevant validity criteria were met.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

inspected: August 2005; signature: November 2005

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Recognised Supplier
- Age at study initiation: 12 to 20 weeks
- Weight at study initiation: 2.0 to 3.5 kg
- Housing: Individually housed in suspended cages.
- Diet (ad libitum): Certified Rabbit diet (Recognised Supplier); provided ad libitum
- Water (ad libitum): mains drinking water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23
- Humidity (%): 30 to 70
- Air changes (per hr): at least 15
- Photoperiod (hrs dark / hrs light): 12 h light / 12 h dark

IN-LIFE DATES: From: 27-03-2007 To: 03-04-2007

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 mL
- Concentration (if solution): Not applicable.

VEHICLE
- Amount applied: Not applicable.

Duration of treatment / exposure:

4 hours

Observation period:

72 hours (initial observation); additional observations are made daily up to Days 7 and 14 to assess the reversibility of skin reactions (as appropriate).

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: dorsal
- Type of wrap if used: semi-occlusive (2.5 cm x 2.5 cm cotton gauze patch secured with surgical adhesive tape)

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Yes, any residual test item removed by gentle swabbing with cotton wool soaked in distilled water.
- Time after start of exposure: 4 hours. Earlier if appropriate based on observations.

OBSERVATION TIME POINTS
(indicate if minutes, hours or days): 1 hour, 4 hours, 24 hours, 48 hours and 72 hours. Additional observations daily up to 7 or 14 days, as appropriate

SCORING SYSTEM: Draize Scale:
Erythema and Eschar Formation
No erythema _______________________________________________________ 0
Very slight erythema (barely perceptible) __________________________________ 1
Well-defined erythema ________________________________________________ 2
Moderate to severe erythema ___________________________________________3
Severe erythema (beet redness) to slight 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 millimetre) _______________________________ 3
Severe oedema (raised more than 1 millimetre and extending beyond the area of exposure) ___4
Any other skin reactions and clinical signs of toxicity, if present, were also recorded.

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

1.77

Max. score:

4

Reversibility:

not fully reversible within: Slight desquamation at day 7

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 7 days

Remarks:

Slight desquamation at day 7

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.33

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 7 days

Remarks:

Slight desquamation at day 7

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.33

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 7 days

Irritant / corrosive response data:

See table 1.

Other effects:

- Other adverse local effects: None reported.
- Other adverse systemic effects: None reported. Individual bodyweights were not reported during the study.

Table 1. Individual Scores and Mean Scores following 4-hour exposure

Skin Reaction	Reading (hours)	1# Male	#2 Male	3# Male
Erythema/Escar Formation	24	2	2	2
	48	2	2	1
	72	2	2	1
	Total	4.0	4.0	4.0
	Mean	2.0	2.0	1.33
Oedema Formation	24	2	1	1
	48	1	1	1
	72	1	1	0
	Total	4.0	3.0	2.0
	Mean	1.33	1.0	0.67

 

At day 7 all eryhema/eschar scores were Zero (0) and all edema scores were Zero (0). Individual #1 and #2 at 7 days indicated 'slight desquamation'

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study, the test item is not considered to be irritating.

Executive summary:

The study was performed to OECD TG 404 and EU Method B.4 in accordance with GLP to assess the primary skin irritancy potential of the test item in New Zealand White rabbits. The test item was applied sequentially by semi-occluded application to the intact rabbit skin with 0.5 mL test item introduced under a 2.5 cm x 2.5 cm cotton gauze patch onto the clipped skin. The patch was secured in position with a strip of surgical adhesive tape. After exposure to the test item, the patches were removed and individual dose sites were scored at approximately 1, 24, 48, and 72 hours. No corrosive effects were noted. Well-defined erythema and slight oedema were noted. Mean scores for following grading at 24, 48 and 72h were score = 2.0 , 2.0 and 1.67 in erythema and eschar and score = 1.33, 1.0 and 0.67 in oedema scoring criteria. Slight desquamation persisted to day 7 in two of three treated sites. One site appeared normal at the 7-day observation. Under the conditions of the study, the test item is not considered to be a skin irritant.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

other justification

Justification for data waiving:

an in vitro eye irritation study does not need to be conducted because adequate data from an in vivo eye irritation study are available

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
In accordance with REACH Regulation (EC) No. 1907/2006 Annex VII, column 2 section 8.1.2 (as amended by Commission Regulation (EU) 2016/863) the serious eye damage / eye irritation (OECD TG 437 or OECD TG 438) study does not need to be conducted based on the available information allowing a definitive conclusion on the classification of the substance. An available in vivo (OECD TG 405) eye irritation study is available that indicates that the substance is not eye irritating and a definitive conclusion on the classification can be made. According to ECHA Guidance on Information Requirements and Chemical Safety Assessment (Chapter R.7a: Endpoint Specific Guidance, R.7.2, July 2017) the study does not need to be conducted.

Reference 2

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10-04-2007 to 19-04-2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP. All relevant validity criteria were met.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

inspected: August 2005; signature: November 2005

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Recognised Supplier
- Age at study initiation: 12 to 20 weeks
- Weight at study initiation: 2.0 to 3.5 kg
- Housing: Individually housed in suspended cages.
- Diet (ad libitum): Certified Rabbit diet (Recognised Supplier); provided ad libitum
- Water (ad libitum): mains drinking water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23
- Humidity (%): 30 to 70
- Air changes (per hr): at least 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 hour light / 12 hour dark

IN-LIFE DATES: From: 10-04-2007 To: 19-04-2007

Vehicle:

unchanged (no vehicle)

Controls:

other: left eye remained untreated

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL ; which was determined to weigh approximately 91 mg (measured by gentle compacting into adapted syringe).
- Concentration (if solution): undiluted

VEHICLE
- Amount(s) applied (volume or weight with unit): Not applicable.
- Concentration (if solution): Not applicable.

Duration of treatment / exposure:

A volume of 0.1 mL of the test item, was placed 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 treatment, to prevent loss of the test item, and then released. The left eye remained untreated and was used for control purposes. Irrigation of the eye with distilled water or saline, after 1 hour was deemed not necessary during the study.

Observation period (in vivo):

Ocular assessment was conducted at approximately 1, 24, 48 and 72 hours after instillation of the test item, according to numerical evaluation.

Number of animals or in vitro replicates:

3 (male). Testing was conducted sequentially following testing with a sentinel.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): none

SCORING SYSTEM:
The irritation was assessed according to Draize (1977) numerical scoring system. At each observation period, the highest scores given were recorded. Any other ocular effects were also noted.

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:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

0.4

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0.2

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

No corneal effects were noted, all scores were zero.
No iridial effects were noted, all scores were zero.
Moderate conjunctival irritation (score = 2) was noted in all treated eyes 1 h after treatment. Chemosis and Redness was minimal (score = 1 to 0) at the 24 h observation in all treated eyes and all effects had reversed (score = 0) at the 72 h observation.

Other effects:

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

Table 1.0: Individual and Mean Scores for Cornea, Iris and Conjunctivae

Number and Sex	Time After Treatment	Corneal Opacity		Iridial Inflammation	Conjunctival Redness	Conjunctival Chemosis
1# Male	24 Hours	0		0	1	0
	48 Hours	0	0		0	0
	72 Hours	0	0		0	0
Total		0		0	1	1
Mean		0.0		0.0	0.3	0.0
#2 Male	24 Hours	0		0	1	1
	48 Hours	0	0		1	0
	72 Hours	0	0		0	0
Total		0		0	2	1
Mean		0.0		0.0	0.7	0.3
#3 Male	24 Hours	0		0	1	1
	48 Hours	0	0		1	0
	72 Hours	0	0		0	0
Total		0		0	2	1
Mean		0.0	0.0		0.7	0.3

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the test item is not irritating to the eye.

Executive summary:

The study was performed to OECD TG 405 and EU Method B.5 guidelines under GLP to assess the irritancy potential of the test item to the eye following a single application in the New Zealand White rabbit. A volume of 0.1 mL of the test item was placed into the conjunctival sac of one eye of three animals. The other eye remained untreated and was used for control purposes. The test was conducted in a stepwise manner conducted singularly and then on a further two rabbits in accordance with the guideline. Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment. A single application of the test item to the non-irrigated eye of three rabbits produced no corneal opacity, iridial inflammation and moderate conjunctival irritation (redness, score = 2) at one hour which was minimal (redness and chemosis, score = 1 to 0) after 24 hours. All treated eyes appeared normal at the 72-Hour observation (score = 0). Under the conditions of this study, the test item is not considered to be irritating to the eye.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Skin Irritation:

Key study : in vivo, OECD TG 404, 2007 : The study was performed to OECD TG 404 and EU Method B.4 in accordance with GLP to assess the primary skin irritancy potential of the test item in New Zealand White rabbits. The test item was applied sequentially by semi-occluded application to the intact rabbit skin with 0.5 mL test item introduced under a 2.5 cm x 2.5 cm cotton gauze patch onto the clipped skin. The patch was secured in position with a strip of surgical adhesive tape. After exposure to the test item, the patches were removed and individual dose sites were scored at approximately 1, 24, 48, and 72 hours. No corrosive effects were noted. Well-defined erythema and slight oedema were noted. Mean scores for following grading at 24, 48 and 72h were score = 2.0 , 2.0 and 1.67 in erythema and eschar and score = 1.33, 1.0 and 0.67 in oedema scoring criteria. Slight desquamation persisted to day 7 in two of three treated sites. One site appeared normal at the 7-day observation. Under the conditions of the study, the test item is not considered to be a skin irritant.

 

Applicant assessment indicates: that the CLP Regulation (EC) 1272/2008 Skin Irritation : category 2 classification within the inflammation criteria (erythema/eschar and oedema) being mean score at 24, 48 and 72 h > or = 2.3 in  two of three sites was not met. The study was originally classified under DSD 67/548/EEC which utilised a mean score of 2.0 for positive result. The study was terminated on day 7 under DSD 67/548/EEC, all inflammation had ceased although ‘slight desquamation’ persisted in two of three sites to day 7. It could be envisaged that all effects may have reversed and full repair may have occurred by day 14 had the study not been terminated. The substance should be more properly classified under GHS Skin Irritation Category 3: Mild Irritant.

 

Eye Irritation:

Key study : In vivo, OECD TG 405, 2007 : The study was performed to OECD TG 405 and EU Method B.5 guidelines under GLP to assess the irritancy potential of the test item to the eye following a single application in the New Zealand White rabbit. A volume of 0.1 mL of the test item was placed into the conjunctival sac of one eye of three animals. The other eye remained untreated and was used for control purposes. The test was conducted in a stepwise manner conducted singularly and then on a further two rabbits in accordance with the guideline. Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment. A single application of the test item to the non-irrigated eye of three rabbits produced no corneal opacity, iridial inflammation and moderate conjunctival irritation (redness, score = 2) at one hour which was minimal (redness and chemosis, score = 1 to 0) after 24 hours. All treated eyes appeared normal at the 72-Hour observation (score = 0). Under the conditions of this study, the test item is not considered to be irritating to the eye.

 

Respiratory Irritation:

INHALATION:

Key study : OECD TG 436, 2018 : The study was performed according to OECD TG 403 accordance with GLP to assess the acute inhalation toxicity of the test item. A single group of ten RccHan : WIST strain rats (five males and five females) were exposed to an aerosol atmosphere of the test item. The groups were exposed for four hours using a nose only exposure system, followed by a fourteen day observation period. During preliminary characterisation trials a 5 mg/L test item aerosol atmosphere could not be achieved. A maximum practical exposure level was targeted. The mean achieved aerosol concentration value was lower than anticipated due to generation problems (atomizer needle blocking). The characteristics of the atmosphere were as follows: Group 1: 5.00 mg/L (target concentration) or 2.08 mg/L time-weighted mean measured concentration. The characteristics of the achieved atmosphere was Mean Mass Median Diameter (particle size) and Inhalable Fraction <7 μm and the Geometric Standard Deviation was : 2.3 μm and 87%, was 2.6, respectively. There was no mortalities during the study. Immediately after the exposure, swaying was observed in two males and all females, unsteady gait was observed in all males/females. Swaying had resolved 1 hour post exposure. Unsteady gait had resolved in all males/females, with the exception of one male 2 hours post exposure. This sign had resolved by the end of day 1. Partially closed right eyelid was observed in one male immediately after exposure and chin rubbing was observed in one male immediately after exposure. These signs had resolved in both males 1 hour post exposure. Wet rales were observed in one male and one female 1 hour post exposure. At 2 hours post exposure, wet rales were observed in one male and two females and were still present at the end of day 1 in all males/females observed with this sign. On the day following exposure, wet rales were present at the morning check in one male and one female. This sign had resolved by the end of day 2 and was not observed for the remaining observation period. Piloerection was observed for one male and one female 1 hour and 2 hours post exposure. At the end of day 1 piloerection was observed for these males/females and an additional female. This sign had resolved by the morning check of day 2. Dull eyes and vocalisation were observed for one female 1 hour post exposure and both signs had resolved by day 2. On one occasion, on Day 4, dry rales were observed at the morning check for one male. This had resolved by the end of day 4. There were no clinical signs at the end of the observation period. On day 2, following exposure slight body weight loss was observed in all males. Body weight gain was seen in four of five females with one female maintaining body weight on day 2. Body weight gain was observed on the next weighing occasion (day 4) for all males and two females. On Day 8, body weight gain was observed in all males/females and continued for the remainder of the observation period. No macroscopic abnormalities were observed at the end of the observation period. Under the conditions of this study, the mean maximum attainable atmosphere concentration over 4 hours was 2.08 mg/L. The inhalation 4h-LC50 (male/female) was considered to be > 2.08 mg/L within the Wistar (RCCHan: WIST) strain rat.

 

Applicant assessment indicates: at mean maximum achieved concentration 2.08 mg/L using a target concentration of 5.0 mg/L the MMAD was between 1 to 4 µm and GSD < 3.0 (actual MMAD = 2.3 µm and GSD = 2.6). It was considered that within this study, the test item could not achieve an atmosphere concentration of 5 mg/L and/or equivalent particle size of 1 to 4 μm due to the properties of the test item. The test item was causing blockages of the nebulizer syringe at higher concentrations. OECD TG 403 guideline discourages further testing above 2 mg/L unless a respirable particle sizes may be achieved, and the results are directly relevant for the protection of human health. Less than 50% mortality was achieved at the maximum attainable concentration, therefore further testing was not necessary.

 

References:

1. OECD TG 403 (2009)

2. OECD 39 (2009)

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, further in vitro skin corrosion testing does not need to be conducted based on the available information allowing a definitive conclusion on the classification of the substance. The substance does not demonstrate sufficient skin corrosion potential necessary for classification and labelling. The substance was not classified within an available skin irritation in vivo assay (OECD TG 404) for skin irritation. Applicant assessment indicates: that the CLP Regulation (EC) 1272/2008 Skin Irritation : category 2 classification within the inflammation criteria (erythema/eschar and oedema) being mean score at 24, 48 and 72 h > 2.3 in two of three sites was not met. The study was originally classified under DSD 67/548/EEC which utilised a mean score of 2.0 for positive result. The study was terminated on day 7 under DSD 67/548/EEC, all inflammation had ceased although ‘slight desquamation’ persisted in two of three sites to day 7. It could be envisaged that all effects may have reversed and full repair may have occurred by day 14 had the study not been terminated. The substance should be more properly classified under GHS Skin Irritation Category 3: Mild Irritant.

 

For eye irritation, the weight of evidence indicates that the substance has the potential to cause transient irritating effects to the eye which are insufficient for classification based on the mean scoring and evaluation of the results in three organisms demonstrating that the EU criteria had been met. Effects in vivo on corneal opacity and iritis are low to non-existent and conjunctival effects are low to non-existent all of which fully reversed within 72 hours; the overall evidence is indicative of mild transient and reversible effects on the eye.

 

Within the respiratory route, there were some indications (wet rales) of sensory irritation, however, there was an absence of other relevant clinical signs and/or macroscopic correlates and/or body weight declines that persisted during the study period. As a consequence, the substance is not classified for respiratory irritation or local cytotoxic effects in the respiratory tract.

 

References:

1. Guidance on Application of the CLP Criteria, ECHA, version 5.0, July 2017