Benzenesulfonic acid, 4-C10-13-sec-alkyl derivs., compds. with ethanolamine

Endpoint summary

Description of key information

The irritation effects are produced by both the dissociation products (MEA and LAS) of the registered substance. Therefore, an experimental study on MEA-LAS will provide adequate information for hazard identification and classification for irritation. An in vitro skin corrosivity study was conducted in 2018 with the undiluted test substance MEA-LAS. The results of this study are summarised below. The other supporting study (conducted with 50% MEA-LAS) results are also summarised to support the results of the key study.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From Feb. 14, 2018 to Feb. 16, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Reconstructed Human Epidermis (RHE) Test Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Method B.40bis of Commission Regulation (EC) No 440/2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

(UK, OECD and EC Commission Directive principles of GLP)

Test system:

human skin model

Source species:

human

Cell type:

other: Epithelial, derived from human skin, and formed into a stratified, cornified epithelium

Details on animal used as source of test system:

No animal was used as source of test system.

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EPIDERM™ Human Skin Model
- Supplier: MatTek In Vitro Life Sciences Laboratories, Bratislava, Slovakia
- EpiDermTM Tissues (0.63cm2) lot number: 25878
- Assay Medium lot number: 020818ALD
- Date received: 13 February 2018
- Date of initiation of testing: 14 February 2018

TEMPERATURE USED FOR TEST SYSTEM
- Storage prior to test: The sealed 24-well plate was stored in a refrigerator until use.
- Temperature used during treatment / exposure: Room temperature and incubator (37°C)
- Temperature of post-treatment incubation: Room temperature (overnight)

REMOVAL OF TEST MATERIAL AND CONTROLS:
- Volume and number of washing steps: After the appropriate exposure time, Dulbecco’s Phosphate Buffered Saline (DPBS) (without Ca++ Mg++) was used for rinsing to remove any residual test substance. Rinsing was achieved by filling and emptying each tissue twenty times for approximately 40 seconds using a constant soft stream of DPBS.
- Observable damage in the tissue due to washing: No

MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1.0 mg/mL (prepared from a MatTek MTT-100 kit immediately prior to usage)
- MTT extractant solution: 2 mL Isopropanol
- Incubation time: 3 hours
- Spectrophotometer: Labtech LT-4500 microplate reader
- Wavelength: 570 nm

FUNCTIONAL MODEL CONDITIONS WITH REFERENCE TO HISTORICAL DATA: No details were provided in the source.

NUMBER OF REPLICATE TISSUES: Two. One 6-well plate was used for each exposure period. Two cells in the 6-well plate were assigned for each negative control, test substance and positive control.

CONTROL TISSUES USED IN CASE OF MTT DIRECT INTERFERENCE: No interference of the test substance with MTT. The MTT solution containing the test substance did not turn blue/purple indicating that the test substance did not reduce MTT.

NUMBER OF INDEPENDENT TEST SEQUENCES / EXPERIMENTS TO DERIVE FINAL PREDICTION: One for each exposure period

PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be corrosive to skin if the viability after 3 minutes exposure is less than 50%, or if the viability after 3 minutes exposure is greater than or equal to 50 % and the viability after 1 hour exposure is less than 15%.
- The test substance is considered to be non-corrosive to skin if the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%.

Control samples:

yes, concurrent negative control

Amount/concentration applied:

TEST MATERIAL
- Amount applied: 50 μL
- Concentration: 20% formulation (nominal) corresponding to 19.01% formulation (measured)

VEHICLE: No

NEGATIVE CONTROL
- Amount applied: 50 μL sterile distilled water
- Concentration: Not applicable

POSITIVE CONTROL
- Amount applied: 50 μL Potassium Hydroxide
- Concentration: 8.0 N

Duration of treatment / exposure:

3 and 60 minutes

Duration of post-treatment incubation (if applicable):

3 hours

Number of replicates:

One 6-well plate was used for each exposure period. Two cells in 6-well plate were assigned for each negative control, test substance and positive control.

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minute exposure period

Value:

107.5

Vehicle controls validity:

not examined

Negative controls validity:

valid

Remarks:

(According to OECD guideline 431, the mean OD570 of the two negative control tissues should be ≥ 0.8 and ≤ 2.8 for each exposure time. The mean OD570 was 1.737 for the 3-minute exposure period and 1.815 for the 60-minute exposure period.)

Positive controls validity:

valid

Remarks:

(According to OECD guideline 431, the mean viability of the tissue replicates exposed for 1 hour with the positive control (8 N KOH) should be ≤15%. The mean viability for tissues were 5.3 and 3.7% for the 3 and 60 minute exposure periods, respectively.)

Remarks on result:

other: The test substance was considered to be non-corrosive to the skin.

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

60 minute exposure period

Value:

62.6

Vehicle controls validity:

not examined

Negative controls validity:

valid

Remarks:

(According to OECD guideline 431, the mean OD570 of the two negative control tissues should be ≥ 0.8 and ≤ 2.8 for each exposure time. The mean OD570 was 1.737 for the 3-minute exposure period and 1.815 for the 60-minute exposure period.)

Positive controls validity:

valid

Remarks:

(According to OECD guideline 431, the mean viability of the tissue replicates exposed for 1 hour with the positive control (8 N KOH) should be ≤15%. The mean viability for tissues were 5.3 and 3.7% for the 3 and 60 minute exposure periods, respectively.)

Remarks on result:

other: The test substance was considered to be non-corrosive to the skin.

Other effects / acceptance of results:

OTHER EFFECTS:
- Visible damage on test system: No
- Direct-MTT reduction: The MTT solution containing the test substance did not turn blue/purple, indicating the test substance did not reduce MTT.
- Color interference with MTT: The solution containing the test substance did not become colored, indicating the test substance did not have the potential to cause color interference.

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: Yes. According to OECD guideline 431, the mean OD570 of the two negative control tissues should be ≥ 0.8 and ≤ 2.8 for each exposure time. The mean OD570 was 1.737 for the 3-minute exposure period and 1.815 for the 60-minute exposure period.
- Acceptance criteria met for positive control: Yes. According to OECD guideline 431, the mean viability of the tissue replicates exposed for 1 hour with the positive control (8 N KOH) should be ≤15%. The mean viability for the positive control treated tissues were 5.3 and 3.7% for the 3 and 60 minute exposure periods, respectively.
- Acceptance criteria met for variability between replicate measurements: Yes. In the range 20 and 100% viability, the Coefficient of Variation (CV) between tissue replicates should be ≤ 30%. The CV between the two tissue replicates of each treatment group did not exceed 30%.

Table 1: Mean OD570 values and viabilities for the negative control, positive control and test substance (Study# 98499)

Tissue	Exposure period	Mean OD570 of individual tissues	Mean OD570 of duplicate tissues	Standard Deviation	Coefficient of Variation (%)	Relative Mean Viability (%)
Negative control	3 minutes	1.679	1.737	0.082	4.7	100*
		1.795
	60 minutes	1.831	1.815	0.023	1.2
		1.799
Positive control	3 minutes	0.098	0.093	0.008	na	5.3
		0.087
	60 minutes	0.064	0.068	0.006	na	3.7
		0.072
Test substance	3 minutes	1.944	1.867	0.109	5.8	107.5
		1.790
	60 minutes	1.216	1.137	0.112	9.9	62.6
		1.057

OD = Optical density

* = The mean percentage viability of the negative control tissue is set at 100%

na = Not applicable

Interpretation of results:

GHS criteria not met

Conclusions:

In an in vitro test for skin corrosion using the EpiDerm™ Human Skin Model, benzenesulfonic acid, mono- C10-13-alkyl derivs., MEA salts (CAS RN 85480-55-3; 19.01% active) was considered to be non-corrosive to the skin after treatment periods of 3 and 60 minutes.

Executive summary:

An in vitro study was conducted to evaluate the corrosivity potential of benzenesulfonic acid, mono- C10-13-alkyl derivs., MEA salts (CAS RN 85480-55-3; 19.01% active) according to OECD guideline 431 and EU Method B.40bis using the EpiDerm™ Human Skin Model.

Duplicate EpiDerm™ tissues were treated with the test substance for exposure periods of 3 and 60 minutes. Negative control (sterile distilled water) and positive control (8.0 N potassium hydroxide) groups were also treated for each exposure period. At the end of the exposure period, the tissues were rinsed, before each tissue was taken for MTT-loading. After MTT loading each tissue was placed in 2 mL isopropanol for MTT extraction.

At the end of the formazan extraction period each well was mixed thoroughly and triplicate 200 μL samples were transferred to the appropriate wells of a pre-labelled 96-well plate. The optical density (OD) was measured at 570 nm (OD570).

The acceptance criteria for negative control and positive control groups were met in the study. The mean OD570 for negative control treated tissues was 1.737 for the 3-minute exposure period and 1.815 for the 60-minute exposure period. The mean viability for the positive control treated tissues were 5.3 and 3.7% for the 3 and 60 minute exposure periods, respectively. The coefficient of variation (CV) between tissue replicates did not exceed 30%.

The relative mean viabilities for test substance were 107.5 and 62.6% for 3 and 60 minutes exposure periods, respectively. Based on the mean viabilities, the test substance was categorized as non-corrosive.

In an in vitro test for skin corrosion using the EpiDerm™ Human Skin Model, benzenesulfonic acid, mono- C10-13-alkyl derivs., MEA salts (CAS RN 85480-55-3; 19.01% active) was considered to be non-corrosive to the skin after treatment periods of 3 and 60 minutes.

This skin corrosion test is classified as acceptable and satisfies the guideline requirement for the current OECD guideline 431 (In vitro skin corrosion: Reconstructed Human Epidermis (RhE) test method).

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

17 July 1992

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

other: albino

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. Zimmermann, Schweizer Hof, D-73453 Untergroningen/Aalen
- Age at study initiation: Not specified
- Weight at study initiation: Not specified
- Housing: Individually in wire grating cages
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-22
- Humidity (%): 30-70
- Air changes (per hr): Not specified
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To: March 08, 1994 to March 18, 1994

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.05 mL

Duration of treatment / exposure:

4 hours

Observation period:

10 days

Number of animals:

3

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 4 days

Interpretation of results:

GHS criteria not met

Conclusions:

Under the study conditions, the test substance was not irritating to rabbit skin.

Executive summary:

A primary dermal irritation study was conducted with the test substance according to OECD Guideline 404 (1992), under GLP conditions. 0.05 mL of the undiluted test substance was applied on to shaved area in the back of three albino rabbits. The area was covered with an occlusive bandage for 4 hours. After removing the bandage, the exposed area was washed with water and the dermal reactions were observed for a period of 10 days. A dermal irritation in the form of a well-defined erythema and a very slight oedema in all the treated rabbits. All reactions were fully reversible within 4 days of exposure. Under the study conditions, the test substance was not irritating to rabbit skin (Grunert, 1994).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 24, 1986-May 12, 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Species:

rabbit

Strain:

other: New Zealand albino

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Froxfield Rabbits and Buckmasters
- Age at study initiation: 9-13 weeks
- Weight at study initiation: 2.1-3.1 kg
- Housing: individually housed in metal cages, identified by aluminum ear tags
- Diet (e.g. ad libitum): SDS Standard Rabbit Diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation: yes


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 degree C
- Humidity (%): 30-70
- Air changes (per hr): 19
- Photoperiod (hrs dark / hrs light): 12 hrs light/12 hrs dark

IN-LIFE DATES: From: March 24, 1986 To: May 12, 1986

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

0.1 mL aliquot of P-500 N-Na

Duration of treatment / exposure:

For three rabbits the eyelids were then gently held together for one second before releasing.
For three other rabbits the eyes were irrigated with water for 5 minutes following a 4-second exposure.
For the remaining three rabbits the eyes were irrigated for 5 minutes following a 30-second exposure.

Observation period (in vivo):

Eyes were examined after 1 hour and 1, 2, 3, 4, 7, 14 and 21 days after exposure.

Number of animals or in vitro replicates:

9

Details on study design:

SCORING SYSTEM: Draize scale

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2.3

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.7

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.7

Max. score:

2

Reversibility:

not reversible

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

fully reversible

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not reversible

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.7

Max. score:

3

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Irritant / corrosive response data:

The following results were noted:
1) Three animals without any rinsing:  averaged irritation scores (24, 48, 72 hours) for each animal: cornea 2.3, 1.7, 2; iris: 1.3, 0, 0; conjunctivae redness: 3, 1.7, 2; conjunctivae chemosis: 3, 2, 2.  In the first animal the effects were persistent at day 21.
2) Three animals with rinsing for five minutes following a 30 second exposure: averaged scores: cornea 0.7, 1, 1.3; iris: 0, 0.7, 0.3; conjunctivae redness: 1.7, 2, 1.3; conjunctivae chemosis: 2, 1.3, 2.  The eyes were normal 7 or 14 days after instillation.
3) Three animals with rinsing for five minutes following a 4 second exposure: averaged scores: cornea 0.7, 2.3, 0.7; iris: 0, 0, 0; conjunctivae redness: 1.7, 1.7, 1; conjunctivae chemosis: 1.3, 2, 1.  The eyes were normal 7 days after instillation.

Findings lead to a definition of irritating for LAS at 47% applied without rinsing, irritating (even if with lower effects, mainly as cornea opacity and conjunctivae redness) with rinsing after 30 second of exposure, and not irritating with rinsing after 4 second of exposure.

Results of Eye Irritation Study – No Rinsing

		Hours				Days
Animal		1	24	48	72	4	7	14	21
1	Cornea	2	1	2	4	3B	3B	3BC	3BC
	Iris	0	1	1	2	1	1	1	0
	Conjunctiva - Erythema	1	3	3	3	3	3	2	1
	Conjunctiva – Chemosis	2	3	3	3	3	2	2	1
2	Cornea	1	1	2	2	2	1	0
	Iris	0	0	0	0	0	0	0
	Conjunctiva - Erythema	1	1	2	2	1	0	0
	Conjunctiva – Chemosis	1	2	2	2	1	0	0
3	Cornea	1	2	2	2	2	1	0
	Iris	0	0	0	0	1	0	0
	Conjunctiva - Erythema	1	2	2	2	2	1	0
	Conjunctiva – Chemosis	1	2	2	2	2	0	0

Results of Eye Irritation Study – Rinsing after 4 Seconds

		Hours				Days
Animal		1	24	48	72	4	7
1	Cornea	0	0	1	1	1	0
	Iris	0	0	0	0	1	0
	Conjunctiva - Erythema	1	2	2	1	2	0
	Conjunctiva – Chemosis	2	2	1	1	1	0
2	Cornea	0	2	3	2	0	0
	Iris	0	0	0	0	0	0
	Conjunctiva - Erythema	1	2	2	1	2	0
	Conjunctiva – Chemosis	2	2	2	1	1	0
3	Cornea	0	1	0	1	1	0
	Iris	0	0	0	0	0	0
	Conjunctiva - Erythema	1	1	1	1	2	0
	Conjunctiva – Chemosis	2	1	1	1	1	0

Results of Eye Irritation Study – Rinsing after 30 Seconds

		Hours				Days
Animal		1	24	48	72	4	7	14
1	Cornea	0	1	0	D	D	1	0
	Iris	0	0	0	0	0	0	0
	Conjunctiva - Erythema	1	2	2	1	1	1	0
	Conjunctiva – Chemosis	2	1	1	0	0	0	0
2	Cornea	0	1	1	1	2	0
	Iris	0	0	1	1	0	0
	Conjunctiva - Erythema	1	2	2	2	2	0
	Conjunctiva – Chemosis	2	1	2	1	1	0
3	Cornea	0	1	2	1	2A	2AB	0
	Iris	0	0	0	1	1	1	0
	Conjunctiva - Erythema	1	1	1	2	2	2	0
	Conjunctiva – Chemosis	2	2	2	2	1	1	0

A – Loss of Corneal Epithelium

B – Vascularization

C – Pannus

D – Dulling of the Cornea

Interpretation of results:

Category 1 (irreversible effects on the eye)

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

When not rinsed, damage to the eyes due to the test substance was not reversed within 21 days. According to EU GHS guidelines the test substance is a category 1 eye irritant.

Executive summary:

This study examined the potential of the test substance to cause irritation to eyes. Groups of three rabbits had 0.1 ml of test substance placed in each of their eyes. In one group, the eyes were not rinsed. In the second group, the eyes were rinsed after 4 seconds of exposure. In the third group, the eyes were rinsed after 30 seconds of exposure. Observations were made one hour and 1, 2, 3, 4, 7, 14, and 21 days after exposure. Severe irritation was noted in the animals whose eyes were not rinsed. This irritation was not resolved in one of these animals at the end of 21 days. Irritation was also seen in the animals rinsed after 30 seconds, although the irritation was not as severe, and the effects were fully reversible within 14 days. Mild irritation was seen in the animals rinsed after 4 seconds. These effects were fully reversible within 7 days. Since OECD guideline 405 for eye irritation studies calls for an exposure of at least 24 hrs, the results for unrinsed eyes were used for classification. According to these results, the test substance is a category 1 eye irritant because it caused damage that was not reversible within 21 days.

Reference 2

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

(Purity of the test material was not listed)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Principles of method if other than guideline:

BASF-Test

GLP compliance:

not specified

Species:

rabbit

Strain:

Vienna White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.65-2.89 kg
- Diet: ad libitum
- Water: ad libitum

Vehicle:

unchanged (no vehicle)

Controls:

other: adjacent eye (physiological NaCl-solution)

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.05 mL

Duration of treatment / exposure:

not applicable (tests substance was not washed out)

Observation period (in vivo):

8 days

Number of animals or in vitro replicates:

3

Details on study design:

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

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

iris score

Remarks:

(redness)

Basis:

animal #1

Time point:

24/48/72 h

Score:

1.33

Max. score:

2

Reversibility:

not reversible

Irritation parameter:

iris score

Remarks:

(redness)

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

fully reversible

Irritation parameter:

iris score

Remarks:

(redness)

Basis:

animal #3

Time point:

24/48/72 h

Score:

1.33

Max. score:

2

Reversibility:

fully reversible

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.66

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1.33

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.66

Max. score:

3

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

fully reversible

Irritant / corrosive response data:

Chemical burnings, scars on upper eyelid, purulent secretion, bloody discharge, conjunctival bleedings, iritis, staphyloma, ciliar injections

Readings	Animal	Cornea		Iris	Conjunctiva			Additional findings
		op	ar		red	ch	di
1 h	1	1	-	0	0	0	-	cornea black-red coloured, bloody secretion, constricted pupil, strong secretion
	2	3	-	0	0	0	-	cornea black-grey coloured, bloody secretion, constricted pupil, strong secretion
	3	3	-	0	0	0	-	cornea brown-red coloured, chemical burnings, brown-red secretion
24 h	1	3	-	0	2	1	-	chemical burnings
	2	3	-	0	1	2		chemical burnings
	3	3	-	0	0	2	-	cornea brown-red coloured, chemical burnings, brown-red secretion
48 h	1	3	-	2	2	1	-	crust formation (eyelids)
	2	3	-	-	1	2	-	chemical burning of the eyeball and eyelid
	3	3	-	2	0	2	-	purulent secretion
72 h	1	3	-	2	2	0	-	purulent secretion
	2	3	-	0	0	0	-	purulent secretion, conjunctiva covered with purulent fur
	3	3	-	2	0	2	-	purulent secretion,
8 d	1	3	-	2	2	0	-	purulent secretion
	2	3	-	0	0	0	-	loss of hair
	3	3	-	2	0	0	-	Staphyloma, ciliar injections, conjunctiva white and chemically burned, scar on upper eyelid
Mean 24 -72 h	1	3	-	1.33	2	0.66	-
	2	3	-	0	0.66	1.33	-
	3	3	-	1.33	0	2	-
Mean 24-72 h	1-3	3	-	0.88	0.89	1.33	-

- endpoint not addressed

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Conclusions:

Under the conditions of this in vivo eye irritation test, instillation of 0.05 mL of test substance 2 -aminoethanol was found to be corrosive to rabbit eye. The test material is therefore classified as Category 1 (irreversible effects on the eye) based on GHS criteria.

Executive summary:

The eye irritation potential of 2 -aminoethanol on rabbit eye was determined following methods comparable to the OECD 405 guideline (Acute Eye Irritation / Corrosion).

Three Vienna White rabbits weighing between 2.65 - 2.89 kg were used in this study. Tap water and food was provided to the animals ad libitum.

During treatment, 0.05 mL (50µL) of test susbtance was placed in the conjuctival sac of one eye in three animals. The contralateral eye was not treated and served as control.

All animals were observed several times on the day of treatment and up to 7 - 8 days after the treatment. and only findings after 48 and 72 hours were taken into account for final evaluation.

The mean scores for corneal opacity, conjuctival redness and chemosis obtained over period of 24 - 72 hours was 3, 0.89 and 1.33, respectively.

Corneal opacity was irreversible and conjunctivae redness as well as chemosis was fully reversible in all animals.

Irritant / corrosive reponses like chemical burnings, scars on upper eyelid, purulent secretion, bloody discharge, conjunctival bleedings, iritis, staphyloma, ciliar injections were also recorded in animals during observation phase.

Under the conditions of this in vivo eye irritation test, instillation of 0.05 mL of test substance 2 -aminoethanol was found to be corrosive to rabbit eye. The test material is therefore classified as Category 1 (irreversible effects on the eye) based on GHS criteria.

Reference 3

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Three New Zealand White rabbits per sex were dosed with 0.005 ml. The dose was instilled into the lower conjunctival sac of 1 eye per animal so that a total of 3 right eyes and 3 left eyes were dosed. The eye was evaluated after 1 hour, 4 hours, and 1, 2, 3, 7, 14, and 21 days after dosing

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Vehicle:

not specified

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.005 ml

Duration of treatment / exposure:

not applicable, because substance was not washed out

Observation period (in vivo):

21 days

Number of animals or in vitro replicates:

6 animals (3 per sex)

Details on study design:

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

SCORING SYSTEM:
corneal opacity (scale of 0-4),
area of cornea involved (scale of 1-4),
iritis (scale of 0-2),
conjunctival redness (scale of 0-3),
chemosis (scale of 0-4),
discharge (scale of 0-3)

TOOL USED TO ASSESS SCORE: fluorescein

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 1 hr

Score:

2.5

Max. score:

4

Reversibility:

fully reversible within: 21 days

Irritation parameter:

cornea opacity score

Remarks:

(area)

Basis:

mean

Time point:

other: 1 hr

Score:

2.7

Max. score:

4

Reversibility:

not fully reversible within: 21 days

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 1 hr

Score:

1

Max. score:

2

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Time point:

other: 1 hr

Score:

2.8

Max. score:

3

Remarks on result:

other: necrosis observed in all animals

Irritation parameter:

conjunctivae score

Remarks:

(discharge)

Basis:

mean

Time point:

other: 1 hr

Score:

3

Max. score:

4

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 1 hr

Score:

2.7

Max. score:

4

Irritation parameter:

conjunctivae score

Basis:

other: all animals

Time point:

24 h

Remarks on result:

other: haemorrhagia, necrosis, pus-like ocular discharge

Irritation parameter:

cornea opacity score

Basis:

other: 2 animals

Time point:

72 h

Remarks on result:

other: 2 animals with corneal vascularization

Irritation parameter:

cornea opacity score

Basis:

other: 4 animals

Time point:

7 d

Remarks on result:

other: irregular shaped corneas

Instillation of 0.005 ml of monoethanolamine into rabbit eyes was immediately followed by vocalization that lasted for approximately 10 seconds. By one hour, severe corneal injury (avg. scores of 2.5 and 2.7 for opacity and area), iritis (avg. score of 1.0), and severe conjunctival irritation (avg. scores of 2.8, 2.7 and 3.0 for redness, chemosis and discharge), with necrosis, was observed in all 6 animals. A red to brown ocular discharge was also noted in each animal. All animals exhibited hemorrhaging in addition to necrosis of the conjunctivae at 24 hours. At this time, all animals also had a pus-like ocular discharge. Corneal vascularization was noted in 2 animals by 72 hours and a third animal had vascularization at 14 days.

Irregularly shaped corneas (characterized by surface bulges) were evident in 4 animals by 7 days. Severe irritation persisted in 3 animals through 21 days (corneal opacity and area scores were 4 and 2, respectively); although 3 other eyes developed a normal appearance.

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Conclusions:

Under the conditions of this in vivo eye irritation test, instillation of 0.005 mL of test substance 2-aminoethanol was found to be corrosive to rabbit eye. The test material is therefore classified as Category 1 (irreversible effects on the eye) based on GHS criteria.

Executive summary:

The purpose of this study was to determine irritation potential of 2 -aminoethanol in eyes of New Zealand White rabbits.

Six New Zealand White rabbits (three males and three females) were used in this study. During treatment, 0.005 mL of test susbtance was placed in the lower conjuctival sac of one eye / animal and was not washed out. The contralateral eye was not treated and served as control. Eyes of all animals were evaluated after 1 hour, 4 hour, 1, 2, 3, 4, 14 and 21 days after the treatment.

After one hour, severe corneal injury (avg. scores of 2.5 and 2.7 for opacity and area), iritis (avg. score of 1.0), and severe conjunctival irritation (avg. scores of 2.8, 2.7 and 3.0 for redness, chemosis and discharge), with necrosis, was observed in all 6 animals. Red to brown ocular discharge was noted in each animal. Hemorrhage, necrosis and pus-like ocular discharge was also observed in all animals at 24 hours. After 72 hours, corneal vascularization was evident in 2 animals. It was also observed in third animal after 14 days. Irregularly shaped corneas (characterized by surface bulges) were evident in 4 animals by 7 days. Severe irritation persisted in 3 animals through 21 days (corneal opacity and area scores were 4 and 2, respectively); although 3 other eyes developed a normal appearance. Corneal opacity (based on score and area) was not fully reversible within 21 days.

Under the conditions of this in vivo eye irritation test, instillation of 0.005 mL of test substance 2-aminoethanol was found to be corrosive to rabbit eye. The test material is therefore classified as Category 1 (irreversible effects on the eye) based on GHS criteria.

Reference 4

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1975

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The eye irritation potential of MEA-LAS was determined by applying the test substance simultaneously to 3 rabbit eyes. The treated eyes were observed for signs and symptoms for 35 d (or until reversibility of eye symptoms was observed).

GLP compliance:

no

Remarks:

(pre-GLP)

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

No details on test animal and environmental conditions are provided in study report.

Vehicle:

other: Unchanged test substance was used for Group 1 and 2. In Group 3, water was used as vehicle.

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.1 mL
- Concentration: Undiluted and 10% w/v

Duration of treatment / exposure:

Group 1 and 3: Eye not rinsed after treatment
Group 2: 4 sec

Observation period (in vivo):

35 d (or till reversibility of eye symptoms was observed)

Number of animals or in vitro replicates:

3/ Group

Details on study design:

Number of eyes: 3/treatment

PROCEDURE FOR TREATMENT AND REMOVAL OF TEST SUBSTANCE: The procedure is as follows:
Group 1: Animals were treated with undiluted test substance and the eyes were not rinsed after treatment.
Group 2: Animals were treated with undiluted test substance and eyes were rinsed after 4 sec of treatment.
Group 3: Animals were treated with 10% w/v aqueous solution and eyes were not rinsed.

SCORING SYSTEM: No scoring system is provided in study report.
- Measurement of maximum average score (MAS): The maximum average score was calculated as the average of the highest total score observed for the three animals in a given test group on any one day.

TOOL USED TO ASSESS SCORE: Not reported

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 14 d

Score:

39

Reversibility:

not reversible

Remarks on result:

other: for Group 1 (Undiluted, no rinse)

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 35 d

Score:

31

Reversibility:

not reversible

Remarks on result:

other: for Group 2 (Undiluted, rinse)

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 14 d

Score:

26

Reversibility:

fully reversible within: 14 d

Remarks on result:

other: for Group 3 (10% w/v aq. Solution, no rinse)

Irritant / corrosive response data:

The irritation observed in Group 1, 2 and 3 is as follows:
- Group 1 (Undiluted, no eye rinse): Corneal opacity, vascularization of cornea and iritis developed in all three animals. Pannus formation was observed in two animals on Day 14. A diffuse crimson red coloration of the conjunctivae and considerable swelling with the eyelids about half closed was observed in all three animals.
- Group 2 (Undiluted, with eye rinse): Corneal opacity was observed in all animals till 35 d after treatment. Vascularization of cornea and iritis were observed in all animals. A diffuse crimson red coloration of the conjunctivae with considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals.
- Group 3 (10% w/v aq. solution, no eye rinse): Corneal opacities developed in all three animals. Stippling of the cornea was observed in one animal at 24 h reading. Iritis was observed in all three animals at the 24 h reading only. A diffuse crimson red coloration of the conjunctivae with and without considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals.

Other effects:

- Due to severity of the reactions, all animals of Group 1 were sacrificed on Day 14.
- In Group 2, eyes did not recover to normal condition within 35 d after treatment.
- In Group 3, all three treated eyes recovered to normal condition within 14 d after treatment.

Table 1. Average total P&G score and maximum average score (MAS) after treatment with MEA-LAS (Study # 13566)

Treatment	Average total P&G score									Maximum average score (MAS)
	Day 1	Day 2	Day 3	Day 4	Day 7	Day 14	Day 21	Day 28	Day 35
Undiluted test substance (No rinse); Group 1	29	39	38	37	35	36	-	-	-	39
Undiluted test substance (Rinse); Group 2	24	28	28	31	24	14	6	7	6	31
10% w/v solution (No rinse); Group 3	26	13	7	7	2	0	-	-	-	26

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

(when tested undiluted with or without eye rinse)

Conclusions:

Under the test conditions, instillation of undiluted (with and without eye rinse) or 10% w/v solution (without eye rinse) of MEA-LAS to rabbit’s eye produced eye irritation. The reactions were reversible within 14 days when applied as 10% w/v solution of test material and irreversible when applied undiluted.

Executive summary:

The purpose of this in-vivo test was to evaluate eye irritation potential of MEA-LAS when applied once to rabbit eye.

Three treatment groups (3 eyes /group) were used in study. 0.1 mL of test solution was instilled into rabbit eye. The treatment groups are as follows:

    Group 1: MEA-LAS without eye rinse

    Group 2: MEA-LAS with eye rinse (4 sec after treatment)

    Group 3: 10% w/v aqueous solution without eye rinse

In Group 1, corneal opacity, vascularization of cornea and iritis was observed in all three animals. Pannus formation was observed in two animals on Day 14. A diffuse crimson red coloration of the conjunctivae and considerable swelling with the eyelids about half closed was observed in all three animals.

In Group 2, corneal opacity was observed in all animals until Day 35 after treatment. Vascularization of cornea and iritis were observed in all animals. A diffuse crimson red coloration of the conjunctivae with considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals.

In Group 3, corneal opacities developed in all three animals. Stippling of the cornea was observed in one animal at 24 h reading. Iritis was observed in all three animals at the 24 h reading only. A diffuse crimson red coloration of the conjunctivae with and without considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals.

Due to severity of the reactions, all animals of Group 1 were sacrificed on Day 14.

In Group 2, eyes did not recover to normal condition within 35 d after treatment.

In Group 3, all three treated eyes recovered to normal condition within 14 d after treatment.

The MAS score for Group 1, 2 and 3 was 39, 31 and 26, respectively.

Under the test conditions, instillation of undiluted (with and without eye rinse) or 10% w/v solution (without eye rinse) of MEA-LAS to rabbit’s eye produced eye irritation. The reactions were reversible within 14 days when applied as 10% w/v solution of test material and irreversible when applied undiluted. 

Reference 5

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1970

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

The eye irritation potential of MEA-LAS was determined by applying the test substance simultaneously to 3 rabbit eyes. The treated eyes were observed for signs and symptoms for 35 d (or until reversibility of eye symptoms was observed).

GLP compliance:

no

Remarks:

(pre-GLP)

Species:

rabbit

Strain:

not specified

Details on test animals or tissues and environmental conditions:

No details on test animal and environmental conditions are provided in study report.

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Amount applied: Not reported
- Concentration: Undiluted

Duration of treatment / exposure:

Group 1: Eye not rinsed after treatment
Group 2: Eye rinsed, but rinse time not reported

Observation period (in vivo):

35 d after treatment (or until reversibility of eye symptoms was observed)

Number of animals or in vitro replicates:

3/ Group

Details on study design:

Number of eyes: 3/ treatment

PROCEDURE FOR TREATMENT AND REMOVAL OF TEST SUBSTANCE: The procedure is as follows:

Group 1(No rinse): Animals were treated with undiluted test substance and the eyes were not rinsed after treatment.

Group 2 (Rinse): Animals were treated with undiluted test substance and eyes were rinsed after treatment.

SCORING SYSTEM: No scoring system is provided in study report.
- The maximum average score (MAS) was calculated from the observations of treated eyes.

TOOL USED TO ASSESS SCORE: Not reported

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 35 d

Score:

64.6

Reversibility:

other: 2 eyes did not recover within 35 d and 1 eye recovered within 14 d

Remarks on result:

other: For Group 1 (No rinse)

Irritation parameter:

maximum mean total score (MMTS)

Basis:

mean

Time point:

other: 3 d

Score:

21

Reversibility:

fully reversible within: 3 d

Remarks on result:

other: For Group 2 (Rinse)

Irritant / corrosive response data:

Group 1: Undiluted test substance revealed severe ocular damage that persisted in 2 eyes after 35 d of treatment.
Group 2: Rinsing reduced the ocular involvement but diffuse area of corneal translucency (grade 1) and/or moderate to server conjunctivitis which cleared within 3 d, was observed.

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

(without eye rinse)

Conclusions:

Under the test conditions, instillation of undiluted MES-LAS to the rabbit eye produced severe ocular damage (without eye rinse) and was classified under category 1 (based on OECD GHS classification).

Executive summary:

The purpose of this in-vivo test was to evaluate eye irritation potential of MES-LAS when applied once to rabbit eye.

The two treatment groups (3 eyes /group) used in the study were as follows:

    Group 1: Undiluted MES-LAS without eye rinse

    Group 2: Undiluted MES-LAS with eye rinse

In Group 1, undiluted test substance revealed severe ocular damage that persisted in 2 eyes after 35 d.

In Group 2, rinsing reduced the ocular involvement but diffuse area of corneal translucency (grade 1) and/or moderate to severe conjunctivitis, which cleared within 3 d, was observed.

The MAS score for Group 1 and 2 was 64.6 and 21, respectively.

Under the test conditions, instillation of undiluted MES-LAS to rabbits’ eyes produced severe ocular damage (without rinse) and was classified under category 1 (based on OECD GHS classification).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation 

Study1 (MEA-LAS):  

  

An in vitro skin irritation study was conducted with MEA-LAS according to OECD Guideline 431 and EU Method B.40bis, under GLP. Sterile distilled water was kept as negative control and 8 N potassium hydroxide as positive control. At the end of the exposure period, the tissues were rinsed, before each tissue was taken for MTT-loading. After MTT loading each tissue was placed in 2 mL isopropanol for MTT extraction. At the end of the formazan extraction period each well was mixed thoroughly and triplicate 200 μL samples were transferred to the appropriate pre-labelled 96 -well plates. The optical density (OD) was measured at 570 nm. The acceptance criteria for negative control and positive control groups were met in the study. The relative mean viabilities for test substance were 107.5 and 62.6% for 3 and 60 min exposure periods, respectively. Based on the mean viabilities, the test substance was categorized as non-corrosive to skin (Kern, 2018).  

  

Study 2 (C10-13 LAS):  

A primary dermal irritation study was conducted with the test substance according to OECD Guideline 404 (1992), under GLP conditions. 0.05 mL of the undiluted test substance was applied on to shaved area in the back of three albino rabbits. The area was covered with an occlusive bandage for 4 hours. After removing the bandage, the exposed area was washed with water and the dermal reactions were observed for a period of 10 days. A dermal irritation in the form of a well-defined erythema and a very slight oedema in all the treated rabbits. All reactions were fully reversible within 4 days of exposure. Under the study conditions, the test substance was not irritating to rabbit skin (Grunert, 1994).

 

 

Study 4 (MEA):  

  

A primary skin irritation study was conducted with monoethanolamine (MEA) in Vienna White rabbits according to a method similar to OECD Guideline 404. Two New Zealand White rabbits were used in this study. During the treatment phase, a single application of 0.5 mL of dose solution (20% 2-aminoethanol in water) was applied to an intact site on the back of two rabbits clipped on the previous day. Each application was applied under a cotton pad and held in place with a flannel wrap taped to the fur. The test material was held in place for 4 hours and then washed off after the 4 h examination. As chemical burns were observed at the 4 h observation on all rabbits, this study was terminated. Occlusive application of 2-aminoethanol to intact skin resulted into chemical burns in all rabbits. Under the study conditions, the substance was considered to be corrosive to the skin (Dryzga, 1997).

  

Eye irritation 

  

Study 1 (C10-13 LAS):  

  

An eye irritation study was conducted with C10-13 LAS, sodium salt in New Zealand White rabbits. 0.1 mL of the test substance was instilled into the eyes of groups of three rabbits. In one group, the eyes were not rinsed. In the second group, the eyes were rinsed after 4 seconds of exposure. In the third group, the eyes were rinsed after 30 seconds of exposure. Observations were made one hour and 1, 2, 3, 4, 7, 14, and 21 days after exposure. Severe irritation was noted in the animals whose eyes were not rinsed. This irritation was not resolved in one of these animals at the end of 21 days. Irritation was also seen in the animals rinsed after 30 seconds, although the irritation was fully reversible within 14 days. Mild irritation was seen in the animals rinsed after 4 seconds. These effects were fully reversible within 7 days. Under the study conditions, the test substance was corrosive to the eyes (Liggett and Parcel, 1986). 

Study 2 (MEA):  

  

An acute eye irritation study was conducted with monoethanolamine (MEA) in rabbits according to a method comparable to OECD Guideline 405. Three Vienna White rabbits were used in this study. 0.05 mL of undiluted test substance was placed in the conjunctival sac of one eye. The contralateral eye was not treated and served as control. All animals were observed several times on the day of treatment and up to 7 - 8 days after the treatment. The mean scores for corneal opacity, conjunctival redness and chemosis obtained over period of 24 - 72 h were 3, 0.89 and 1.33, respectively. Corneal opacity was irreversible and conjunctivae redness as well as chemosis was fully reversible in all animals. Under the conditions, instillation of undiluted MEA was found to be corrosive to rabbit eyes (BASF, 1966). 

  

Study 3 (MEA):  

     

An acute eye irritation study was conducted with monoethanolamine (MEA) in New Zealand White rabbits according to a method comparable to OECD Guideline 405. Three male and three female rabbits were used in this study. 0.005 mL of undiluted test substance was placed in the conjunctival sac of one eye. The contralateral eye was not treated and served as control. Eyes of all animals were evaluated after 1 h, 4 h, 1, 2, 3, 4, 14 and 21 days after the treatment. After 1 h, severe corneal injury (avg. scores of 2.5 and 2.7 for opacity and area), iritis (avg. score of 1.0), and severe conjunctival irritation (avg. scores of 2.8, 2.7 and 3.0 for redness, chemosis and discharge), with necrosis, was observed in all 6 animals. Severe irritation persisted in 3 animals through 21 days (corneal opacity and area scores were 4 and 2, respectively). Corneal opacity (based on score and area) was not fully reversible within 21 days. Under the conditions, instillation of undiluted MEA was found to be corrosive to rabbit eyes (Myers, 1988).

Study 4 (MEA-LAS):  

  

An eye irritation study was conducted with MEA-LAS in rabbits. Three treatment groups were used in this study. 0.1 mL of test solution was instilled into the rabbit eyes. In Group 1, corneal opacity, vascularization of cornea and iritis was observed in all three animals. Pannus formation was observed in two animals on Day 14. A diffuse crimson red coloration of the conjunctivae and considerable swelling with the eyelids about half closed was observed in all three animals. In Group 2, corneal opacity was observed in all animals until Day 35 after treatment. Vascularization of cornea and iritis were observed in all animals. A diffuse crimson red coloration of the conjunctivae with considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals. In Group 3, corneal opacities developed in all three animals. Stippling of the cornea was observed in one animal at 24 h reading. Iritis was observed in all three animals at the 24 h reading only. A diffuse crimson red coloration of the conjunctivae with and without considerable swelling and partial eversion of the eyelids or with the eyelids about half closed was observed in all three animals. Due to severity of the reactions, all animals of Group 1 were sacrificed on Day 14. Under the study conditions, instillation of undiluted or 10% w/v solution of MEA-LAS to rabbit eyes produced irreversible eye damage to the eyes (Davies and Liggett 1975).  

  

Study 5 (MEA-LAS):  

  

An eye irritation study was conducted with MEA-LAS in rabbits. Three treatment groups were used in this study. 0.1 mL of test solution was instilled into rabbit eye. In Group 1, undiluted test substance revealed severe ocular damage that persisted in 2 eyes after 35 days. In Group 2, rinsing reduced the ocular involvement but diffuse area of corneal translucency (grade 1) and/or moderate to severe conjunctivitis, which cleared within 3 days, was observed. Under the study conditions, instillation of undiluted MEA-LAS to rabbit eyes produced irreversible eye damage to the eyes (Newmann, 1970).

Justification for classification or non-classification

An in vitro skin corrosion study with undiluted MEA-LAS indicates that MEA-LAS is not corrosive to skin. Thein vivoskin irritation study with 50% MEA-LAS indicates no irritation response. Therefore, based on the weight of evidence from the in vitro and in vivo studies with MEA-LAS and as a worst-case approach, the substance warrants a classification as Skin Irrit. 2 (H315: Causes skin irritation) according to EU CLP (1272/2008/EC) criteria.

 

In vivo eye irritation studies with MEA-LAS as well as its dissociation products (MEA and LAS) in rabbits indicated eye damage or severe irritation effects. Based on the results, MEA-LAS warrants classification as Eye Damage 1 (H318 - causes serious eye damage) according to EU CLP (1272/2008/EC) criteria.​