Fatty acids, C18-unsatd., trimers, 2-ethylhexyl esters

Endpoint summary

Description of key information

Skin irritation (OECD 404): not irritating (based on read-across from CAS 68334-05-4)
Eye irritation (OECD 405) not irritating (based on read-across from CAS 68334-05-4)

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

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

Adequacy of study:

key study

Study period:

13 Apr - 30 Apr 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP - Guideline study. According to the ECHA guidance document "Practical guide 6: How to report read-across and categories (March 2010)", the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

adopted in 2002

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan, Belton, Leics, England
- Age at study initiation: 7-14 weeks
- Weight at study initiation: 1602 - 2455 g
- Housing: Animals were individually housed in labelled cages with perforated floors (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm).
- Diet: Pelleted, Global Diet 2030 (Harlan Teklad®, Mucedola, Milanese, Italy), approximately 100 grams per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) was provided at least three times a week.
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0 (actual range: 18.6 – 19.3)
- Humidity (%): 40-70 (actual range: 43 - 73)
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

other: untreated sites of the same animal served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): 100%

Duration of treatment / exposure:

4 h

Observation period:

72 h
Reading time points: 1, 24, 48 and 72 hours after the removal of the dressings and test substance.

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: 6 cm² on the dorsal area of the skin
- Type of wrap if used: metalline patch of 2x3 cm mounted on Micropore tape, which was wrapped around the abdomen and secured with Coban elastic bandage (Lohmann GmbH, Neuwied, Germany (Metalline) and 3M, St. Paul, Minnesota, U.S.A. (Micropore and Coban))

REMOVAL OF TEST SUBSTANCE
- Washing: dressing was removed and the skin cleaned of residual test substance using tap water and watery ethanol (50% v/v) (water: Elix, Millipore S.A.S., Molsheim, France; ethanol: Merck, Darmstadt, Germany)
- Time after start of exposure: 4h

SCORING SYSTEM: Draize scoring system

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: mean over 24, 48 and 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: mean over 24, 48 and 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: mean over 24, 48 and 72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 h

Irritation parameter:

edema score

Basis:

mean

Remarks:

of all 3 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Remarks on result:

other: Edema (score = 1) were seen in all animals 1 h after exposure only.

Irritant / corrosive response data:

Four hours exposure to 0.5 mL of Fatty acids, C18-unsaturated, dimers, 2-ethylhexyl esters resulted in very slight erythema (fully reversible within 48 h) and very slight edema (fully reversible within 24 h) in the treated skin areas of the three rabbits. The skin irritation resolved within 48 hours after exposure in all animals. There was no evidence of a corrosive effect on the skin.

Other effects:

Sticky remnants of the test substance were present on the skin immediately after removal of the test substance and dry remnants of the test substance were present at the 1 hour observation time point. No staining of the treated skin by the test substance was observed. No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified

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:

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

Adequacy of study:

key study

Study period:

19 Apr - 29 Apr 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP - Guideline study. According to the ECHA guidance document "Practical guide 6: How to report read-across and categories (March 2010)", the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

adopted in 2002

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Harlan, Belton, Leics, England
- Age at study initiation: 7-9 weeks
- Weight at study initiation: 1572-1809 g
- Housing: animals were individually housed in labelled cages with perforated floors (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm)
- Diet: pelleted, Global Diet 2030 (Harlan Teklad®, Mucedola, Milanese, Italy), approximately 100 grams per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) was provided at least three times a week
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0 (actual range: 18.6 – 19.3)
- Humidity (%): 40-70 (actual range: 43 - 67)
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Vehicle:

unchanged (no vehicle)

Controls:

other: the untreated eye served as control

Amount / concentration applied:

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

Duration of treatment / exposure:

24h

Observation period (in vivo):

72 h
Reading time points: 1, 24, 48 and 72 hours after instillation of the test substance

Number of animals or in vitro replicates:

3 (males)

Details on study design:

SCORING SYSTEM: Draize scoring system

TOOL USED TO ASSESS SCORE: 2% fluorescein (Merck, Darmstadt, Germany) in water (adjusted to pH 7.0)

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

of 3 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Irritation parameter:

iris score

Basis:

mean

Remarks:

of 3 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

2

Reversibility:

other: reversibility: not applicable

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

other: mean over 24, 48 and 72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

other: mean over 24, 48 and 72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

other: mean over 24, 48 and 72 h

Score:

0.3

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

of 3 animals

Time point:

other: mean over 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: reversibility: not applicable

Irritant / corrosive response data:

Instillation of 0.1 mL of Fatty acids, C18-unsaturated, dimers, 2-ethylhexyl esters into one eye of each of three rabbits resulted in irritation of the conjunctivae, which consisted of redness and discharge. The irritation completely resolved within 48 hours in all animals.
No iridial irritation or corneal opacity was observed, and treatment of the eyes with 2% fluorescein 24 hours after test substance instillation revealed no corneal epithelial damage. There was no evidence of ocular corrosion.

Other effects:

Remnants of the test substance were present on the outside of the eyelids on Day 1. No staining of (peri) ocular tissues by the test substance was observed. No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for grouping of substances and read-across

There are no data available for the skin irritation/corrosion and eye irritation of Fatty acids, C18 unsatd., trimers, 2-ethylhexyl esters (CAS 173832-46-7). In order to fulfil the standard information requirements set out in Annex VIII, 8.1 and 8.2, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted.

In accordance with Article 13 (1) of Regulation (EC) No 1907/2006, "information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met.” In particular for human toxicity, information shall be generated whenever possible by means other than vertebrate animal tests, which includes the use of information from structurally related substances (grouping or read-across).

Having regard to the general rules for grouping of substances and read-across approach laid down in Annex XI, Item 1.5, of Regulation (EC) No 1907/2006 whereby substances may be predicted as similar provided that their physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity.

Overview of skin and eye irritation:

CAS	173832-46-7 (a)	68334-05-4 (b)
Chemical Name	Fatty acids, C18 unsatd., trimers, 2-ethylhexyl esters	Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters (ESIS: NLP)
Molecular weight	973.62 1085.84 1184.02	673.10
Skin irritation/corrosion	RA: CAS 68334-05-4	Experimental result: not irritating
Eye irritation	RA: CAS 68334-05-4	Experimental result: not irritating

(a) Category members subjected to the REACh  Phase-in registration deadline of 31 May 2013 are indicated in bold font.

Lack of data for a given endpoint is indicated by “--“.

(b) Surrogate substances are indicated in normal font and are precursors/breakdown products of the target substance (i.e. alcohol and fatty acid moieties). Available data on these substances are used for assessment of toxicological properties by read-across on the same basis of structural similarity and/or mechanistic reasoning as described for the present analogue approach.

The above mentioned substances are considered to be similar on the basis of the structural similar properties and/or activities. The available endpoint information is used to predict the same endpoints Fatty acids, C18 unsatd., trimers, 2-ethylhexyl esters (CAS 173832-46-7).

A detailed analogue approach justification is provided in the technical dossier (see IUCLID Section 13).

 

Discussion

Skin irritation

CAS 68334-05-4

The skin irritation potential of Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters was investigated in a GLP-conform study according to OECD guideline 404 (Stitzinger, 2010). The undiluted test substance (0.5 mL) was applied for 4 h to the clipped skin of 3 male New Zealand White rabbits under semiocclusive conditions. The untreated site of the animals served as control. The scoring of skin reactions (erythema and edema) was performed 1, 24, 48 and 72 h after removal of the dressing and cleaning of residual test substance using tap water and watery ethanol (50% v/v). Very slight erythema and very slight edema (grade 1) were observed on the treated skin of the animals. Skin irritation was fully reversible within 24 h (edema) or 48 h (erythema) after exposure to the test substance. No signs of systemic toxicity were observed in the animals during the test period and no mortality occurred. The mean erythema and edema scores after 24, 48 and 72 h were 0.33 and 0 for all 3 animals.

Based on the results of this study, Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters is not irritating to the skin.

Eye irritation

CAS 68334-05-4

An eye irritation study was conducted with Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters according to OECD guideline 405 and in compliance with GLP (Stitzinger, 2010). The undiluted test substance (0.1 mL) was placed into the conjunctival sac of one eye of 3 male New Zealand White rabbits. The other eye remained untreated and served as control. The eyes were examined and scored 1, 24, 48 and 72 h after application. Instillation of the test substance resulted in redness of conjunctivae in all three animals, which was fully reversible at the 48 h reading. In addition, conjunctival discharge was observed in the treated eyes of all animals at the 1 h reading. No iridial irritation and corneal opacity was noted during the study. Treatment of the eyes with 2% fluorescein 24 hours after test substance instillation revealed no corneal epithelial damage. No evidence of ocular corrosion was seen during the study. Furthermore, no symptoms of systemic toxicity and no mortalities occurred in the animals during the test period. The mean cornea, iris and chemosis scores after 24, 48, and 72 h were 0 for all 3 animals, respectively. The mean score for conjunctivae after 24, 48, and 72 h was 0.3 for all 3 animals.

Based on the results of this study, Fatty acids, C18-unsatd., dimers, 2-ethylhexyl esters is not eye irritating.

Conclusion for skin irritation/corrosion and eye irritation

In conclusion, no data is available on the skin and eye irritation potential of Fatty acids, C18 unsatd., trimers, 2-ethylhexyl esters, but there exists reliable studies from the surrogate substance C18-unsatd., dimers, 2-ethylhexyl esters (CAS 68334-05-4), which are used for read-across based on the analogue approach and which are indicating no skin and eye irritating properties. Therefore, Fatty acids, C18 unsatd., trimers, 2-ethylhexyl esters is not skin and eye irritating.

Justification for selection of skin irritation / corrosion endpoint:
Hazard assessment is conducted by means of read-across from a structural surrogate. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for selection of eye irritation endpoint:
Hazard assessment is conducted by means of read-across from a structural surrogate. The selected study is the most adequate and reliable study based on the identified similarities in structure and intrinsic properties between source and target substance and overall quality assessment (refer to the endpoint discussion for further details).

Justification for classification or non-classification

Based on read-across from the surrogate substance, the available data on skin and eye irritation/corrosion do not meet the classification criteria according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.