Registration Dossier

Administrative data

Description of key information

Skin irritation (similar to OECD 404): not irritating

Data read-across from the source substance bis(2-(2-butoxyethoxy)ethyl) adipate (CAS No. 141-17-3)

Eye irritation (OECD 492): not irritating

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:
4 Nov 1997 - 11 Nov 1997
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to an accepted and published method. Experimental documentation was limited but adequate for the purposes of this summary.
Qualifier:
according to
Guideline:
EPA OTS 798.4470 (Acute Dermal Irritation)
Deviations:
no
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
no
GLP compliance:
yes
Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
TEST ANIMALS- Source: Davidson Mill Breeding Laboratories, Jamesburg, New Jersey, USA- Age at arrival: 3 months- Fasting period before study: none- Housing: stainless steel cages- Diet: Lab Diet Certified Rabbit Diet #5322, ad libitum- Water: ad libitum- Acclimation period: 13 daysENVIRONMENTAL CONDITIONS- Temperature (°C): 18 - 24 (65 - 75 °F)- Photoperiod (hrs dark / hrs light): 12/12IN-LIFE DATES: From: To: 4 Nov 1997 to 11 Nov 1997
Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
unchanged (no vehicle)
Controls:
other: not required, untreated sites of the same animal served as control
Amount / concentration applied:
0.5 mL
Duration of treatment / exposure:
4 hours
Observation period:
7 days Reading time points: 4.5, 24, 48, and 72 h and 7 days after treatment)
Number of animals:
6 (3 males, 3 females)
Details on study design:
TEST SITE- Area of exposure: approximately 6 cm²- Type of wrap if used: The area was covered with a 2.5 cm² surgical gauze pad (Johnson & Johnson). This was held in place with 3 inch Johnson & Johnson hypo-allergenic cloth tape, semi-occlusively. Animals were collared for the deration of the exposure to preclude access to the siteREMOVAL OF TEST SUBSTANCE- Washing (if done): Remaining test article was gently washed from the skin with water and paper towels.- Time after start of exposure: 4 hSCORING SYSTEM: Each site was then individually examined and scored at 30 and 60 minutes following unwrapping for erythema and edema according to the Draize Scoring System.OTHERThe hair of the mid-dorsal area of the trunk of each animal, between scapulae and pelvis, was shaved using an Oster small animal clipper with surgical head (#40). Care was taken to avoid abrasion of the skin during clipping. Prior to dose application, animals were placed into wooden restrainers.
Irritation parameter:
erythema score
Basis:
mean
Remarks:
out of all 6 animals
Time point:
24/48/72 h
Score:
0.72
Max. score:
4
Reversibility:
fully reversible within: 7 days
Remarks on result:
other: One animal showed accumulation of loose fragments of horny layer of skin (stratum corneum). Peeling. Only uppermost layer involved.
Irritation parameter:
edema score
Basis:
mean
Remarks:
out of all 6 animals
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: reversibility: not applicable
Other effects:
The animals did not exhibit any abnormal clinical signs for the duration of the study.

Table 1: Primary dermal irritation in rabbits / individual results

Rabbit (number)

4 ½ hr

24 hr

48 hr

72 hr

Day 7

Erythema

Edema

Erythema

Edema

Erythema

Edema

Erythema

Edema

Erythema

Edema

1

1

0

1

0

1

0

0

0

-

-

2

1

0

1

0

1

0

1

0

0

0

3

1

0

1

0

1

0

0

0

-

-

4

1

0

1

0

1

0

1

0

0

0

5

1

0

1

0

1

0

1

0

0

0*

6

1

0

0

0

0

0

0

0

-

-

* Accumulation of loose fragments of horny layer of skin (stratum corneum). Peeling. Only uppermost layer involved.

The primary dermal irritation index was 0.65. The animals in this study did not exhibit any abnormal signs for the duration of the study. Under the conditions of this study, the test article elicited minimal irritation.

 

 

 

Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records
Reference
Endpoint:
eye irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
12 - 19 Jan 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)
Version / remarks:
adopted 28 July 2015
Deviations:
yes
Remarks:
no historical data of positive and negative controls
GLP compliance:
yes (incl. certificate)
Remarks:
GROlJPE lNTERMlNISTERIEL DES PRODUITS CHIMIQUES, 67, rue Barbes, 94201 Ivry-sur-Seine CEDEX, France
Species:
human
Strain:
other: EpiOcular™
Vehicle:
unchanged (no vehicle)
Controls:
yes, concurrent positive control
yes, concurrent negative control
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied: 50 µL
Duration of treatment / exposure:
30 min
Duration of post- treatment incubation (in vitro):
2 h
Number of animals or in vitro replicates:
in duplicates for each treatment and contol group
Details on study design:
- RhCE tissue construct used, including batch number: EpiOcular™ (OCL-212-ver2.0, supplied by MatTek Corporation), batch No. 23759
- Duration and temperature of exposure, post-exposure immersion and post-exposure incubation periods: 30 min exposure (37 °C), 12 min post-exposure immersion (room temperature), 2 h post-exposure (37 °C)
- Indication of controls used for direct MTT-reducers and/or colouring test chemicals: The optical pre-experiment (colour interference pre-experiment) to investigate the test item’s colour change potential in water or isopropanol did not lead to a change in colour. Therefore, an additional test with viable tissues without MTT addition was not necessary. Optical evaluation of the MTT-reducing capacity of the test item with MTT-reagent did not show blue colour. Therefore, an additional test with freeze-killed tissues was not necessary.
- Description of the method used to quantify MTT formazan: The absorbance at 570 nm of each well was measured with a microplate reader (model ELx800, BioTek) and the software Gen5 ELISA V1.05.11 (BioTek). No reference wavelength measurement was used.
- Acceptability criteria: 1) Negative control: OD values of the two replicates in the range> 0.8 and< 2.5; 2) Tissues treated with the positive control substance should show a mean tissue viability < 50%; 3) The difference of viability between two tissue replicates should be less than 20% (or the SD between three replicates should not exceed 18%).
- Decision criteria/Prediction model: If the test item-treated tissue viability is > 60% relative to the negative control treated tissue viability, the test item is identified as not requiring classification and labelling for skin irritation. If the test item-treated tissue viability is ≤ 60% relative to negative control treated tissue viability, the test item is identified as potentially requring classification and labelling for skin irritation.
Irritation parameter:
other: % mean relative absorbance of 2 tissues
Run / experiment:
30 min exposure
Value:
100.32
Vehicle controls validity:
not applicable
Negative controls validity:
valid
Positive controls validity:
valid
Other effects / acceptance of results:
ACCEPTANCE OF RESULTS:
- Acceptance criteria for negative control: The negative control mean OD values (0.684 and 0.585) were not in the range of > 0.8 and < 2.5. Considering the results obtained, this deviation is considered to have no impact on the conclusion of the study.
- Acceptance criteria met for positive control: The mean relative viability of the positive control is below 50% of the negative control viability (5.04%).
- Deviations from acceptability criteria: The difference of viability between 2 tissues for the test item was 34.52%, instead of 20% as initially scheduled. Considering the results obtained, this deviation is considered to have no impact on the conclusion of the study.

Table 1: Results after 30 min incubation time

 

 

 

Tissue

 

OD

 

Mean OD/ disc (#)

 

Mean OD/ product

Viability

%

Meanviability

%

Differenceofviability

%

 

Conclusion

 

 

0.758

 

 

 

 

 

 

 

I

0.635

0.684

 

107.80

 

 

Negativecontrol

 

0.659

 

0.635

 

100.00

15.60

 

0.558

 

 

 

2

0.607

0.585

 

92.20

 

 

 

 

0.590

 

 

 

 

 

 

 

0.032

 

 

 

 

 

 

 

3

0.032

0.032

 

5.04

 

 

 

Positivecontrol

 

0.033

 

0.032

 

5.04

0.00

UN GHS Category 2 or I

 

0.039

 

 

 

4

0.029

0.032

 

5.04

 

 

 

 

 

0.029

 

 

 

 

 

 

 

 

0.622

 

 

 

 

 

 

 

5

0.811

0.746

 

117.57

 

 

 

Test item

 

0.805

 

0.637

 

100.32

34.52

No Category

 

0.519

 

 

 

6

0.517

0.527

 

83.06

 

 

 

 

 

0.545

 

 

 

 

 

 

Note: the optical density was measured after a 1:2 dilution of the formazan extracts in isopropanol.

viab > 60% = No Category

viab </= 60% = Irritant

 

#: :mean of 3 values (triplicate of the same extract)

OD: opticaldensity

Acceptability criteria:

- Negative control: OD values of the two replicates in the range > 0.8 and < 2.5;

- Tissues treated with the positive control substance should show a mean tissue viability < 50%;

- The difference of viability between two tissue replicates should be less than 20% (or the SD between three replicates should not exceed 18%).

Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.
Conclusions:
Under the conditions of the conducted test, the test substance is non irritating towards human-derived epidermal keratinocytes in the EpiOcular™ model.
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

The read-across approach uses 'bis(2-(2-butoxyethoxy)ethyl)adipate' (CAS No. 141-17-3) as structurally similar source substance to transfer (read-across) data to the target substance 'reaction mass of bis[2-[2-(2-butoxyethoxy)ethoxy]ethyl]adipate and [2-[2-(2-butoxyethoxy)ethoxy]ethyl](3,6,9,12-tetraoxahexadecyl)adipate' (EC No. 943-330-9). The common feature of the source substance and the target substance is that they are diester derivatives of adipic acid, containing only even numbered and linear ethoxylated side chains. Both carboxylic functions of adipic acid are used to form esters with ethylene glycol monobutyl ethers of varying length. While the side chains of the target substance contain tri- and/or tetraethylene glycol monobutyl ether moieties, the side chains in the source substance are made up solely of diethylene glycol monobutyl ether. Thus, the ethylene glycol monobutyl ether substituents in the target substance contain 1 or 2 additional ethylene glycol monobutyl ether units. Although the constituents of the target substance are hence larger in size and have a higher molecular weight, it can be assumed that no significant steric hindrance is introduced when compared to the smaller side chains of the source substance. All parts of the ethylene glycol monobutyl ether side chains are freely rotatable due to the fact that neither a ring system nor π-bonds exert any constraints on rotatability. Therefore, it is feasible to assume an identical environmental and metabolic fate of both substances. In order to avoid the need to test every substance for every endpoint, the read-across from an analogue substance concept is applied for the assessment of environmental fate and environmental and human health hazards. Thus, where applicable, environmental and human health effects are predicted using adequate and reliable data from the source substance in accordance with Annex XI, Item 1.5, of Regulation (EC) No. 1907/2006 (REACH). Structural similarity and similarities in properties and/or activities of the source and target substance are the basis of read-across.

Skin irritation / corrosion

No data regarding skin irritation / corrosion obtained with the target substance are available and therefore read-across of adequate information from the source substance is used. A key study was conducted similar to the OECD TG 404 test guideline and in compliance with GLP (Consumer Products Testing, 1997b). Three New Zealand White rabbits received the neat test item at a volume of 0.5 mL on the shaved skin under semiocclusive conditions. After 4 h, the test item was removed by washing of the application sites and the animals were observed and scored for erythema and oedema for up to 7 days. According to the Draize Scoring System the mean erythema score over 24, 48 and 72 h out of all six animals was 0.72, the respective oedema score was 0. The erythema observed was fully reversible within 7 days. One animal showed accumulation of loose fragments of horny layer of skin (stratum corneum), however, only the uppermost layer was involved. The animals in this study did not exhibit any abnormal signs for the duration of the study. In conclusion, the test item was not irritating to the skin under the conditions of the test.

Eye irritation

The eye irritation potential of reaction mass of bis[2-[2-(2-butoxyethoxy)ethoxy]ethyl] adipate and [2-[2-(2-butoxyethoxy)ethoxy]ethyl](3,6,9,12-tetraoxahexadecyl)adipate (EC No. 943-330-9) was investigated in a study according to OECD TG 492 observing GLP conditions (Phycher, 2017). The undiluted test substance was applied at a dose of 50 µL to 2 living RhCE patches (EpiOcular™ tissue model, size 0.60 cm2) for a duration of 30 minutes at 37 °C, 5% CO2 and 95% humidity. The exposure period was followed by extensive rinsing with phosphate buffered saline at room temperature, a 12 minutes post-exposure immersion period at room temperature and a 2 hours post-exposure incubation at 37 °C, 5% CO2 and 95% humidity. The tissue viability was measured by performing an MTT assay. An additional test with viable tissues without MTT addition and an additional test with freeze-killed tissues were not necessary as there was no interference of the test substance with MTT. Adequate positive (methyl acetate) and negative (distilled water) controls were also investigated and yielded the expected results, thus validating the experiment. All applicable acceptability criteria were fulfilled. The mean corrected percent tissue viability of the RhCE replicates treated with the test item was 100.32%, versus 5.04% in the positive control. In conclusion, under the experimental conditions adopted and in accordance with Regulation EC No. 1272/2008 (CLP), the test item does not require classification for eye irritation or serious eye damage.

Conclusion on skin and eye irritation / corrosion

The skin irritation / corrosion properties of the source substance have been investigated in vivo indicating no skin irritating properties. Moreover, the potential of the target substance to induce eye irritation or severe eye damage was studied using an appropriate and validated in vitro method and resulting in no eye irritation. All available data on skin and eye irritation / corrosion indicate a lack of irritating properties of the source and the target substance. No hazard for skin and eye irritation / corrosion is therefore identified for the target substance.

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 (REACH) information on intrinsic properties of substances may be generated by means other than tests, e.g. using information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI states that “substances whose physico-chemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Thus, data gaps can be filled by a read-across approach from a structural analogue source substance to avoid unnecessary animal testing.

The analogue concept is also used to derive the C&L of the target substance taking the properties of the source substance into account. Based on the analogue concept and on data obtained with the target substance, all available data on skin and eye irritation / corrosion do not meet the classification criteria according to Regulation (EC) No. 1272/2008 (CLP) and are therefore conclusive but not sufficient for classification.