Dodecanedioic acid, compound with 2,2',2''-nitrilotriethanol (1:2)

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07 February 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Version / remarks:

26 July 2013

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dodecanedioic acid, compound with 2,2',2''-nitrilotriethanol

EC Number:

285-271-5

EC Name:

Dodecanedioic acid, compound with 2,2',2''-nitrilotriethanol

Cas Number:

85049-97-4

Molecular formula:

C12H22O4.xC6H15NO3

IUPAC Name:

dodecanedioic acid - 2,2',2''-nitrilotriethanol (1:1)

1

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Dihydrogen oxide

Test material form:

solid

Remarks:

paste

Details on test material:

Name as cited in report: DDDA TEA salt
Physical appearance: beige to pale yellow paste
Storage conditions: at room temperature

Specific details on test material used for the study:

- Purity correction factor: 1.25
- Stability at higher temperatures: No, maximum temperature: 25°C
- Irritant or corrosive: yes

Test animals / tissue source

Species:

cattle

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Donor animals: young cattle
- Source: slaughterhouse (Vitelco, 's-Hertogenbosch, the Netherlands)
- Storage, temperature and transport conditions of ocular tissue: eyes were excised by a slaughterhouse employee as soon as possible after slaughter. Subsequently, eyes were collected and transported in physiological saline in a suitable container under cooled conditions.
- indication of any existing defects or lesions in ocular tissue samples: eyes exhibiting defects were discarded.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 750 µL

POSITIVE CONTROL
- Amount(s) applied: 750 µL

NEGATIVE CONTROL
- Amount(s) applied: 750 µL

Duration of treatment / exposure:

10 ± 1 minutes

Duration of post- treatment incubation (in vitro):

120 ± 10 minutes

Number of animals or in vitro replicates:

3

Details on study design:

SELECTION AND PREPARATION OF CORNEAS: The eyes were checked for unacceptable defects by removing them from the physiological saline and holding them in the light. Those exhibiting defects were discarded. The isolated corneas were stored in a petri dish with cMEM containing 1% (v/v) L-glutamine and 1% (v/v) Foetal Bovine Serum. The isolated corneas were mounted in a corneal holder (one cornea per holder) of BASF with the endothelial side against the O-ring of the posterior half of the holder. The anterior half of the holder was positioned on top of the cornea and tightened with screws. The compartments of the corneal holder were filled with cMEM of 32 ± 1°C. The corneas were incubated for the minimum of 1 hour at 32 ± 1°C. After the incubation period, opacity determinations were performed and corneas that had an initial opacity reading higher than 7 were not used. Three corneas were selected at random for each treatment group.

TREATMENT METHOD: holders with corneas were placed in a horizontal position to ensure uniform distribution the solutions over the entire cornea. Corneas were incubated in horizontal position for 10 minutes.

POST-INCUBATION PERIOD: yes, 120 +/- 10 min

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: 1 (with MEM with phenol red (Earle’s Minimum Essential Medium, Life Technologies) and thereafter with cMEM)

- POST-EXPOSURE INCUBATION: 120 ± 10 minutes at 32 ± 1°C in cMEM for opacity measurements and 90 ± 5 minutes at 32 ± 1°C in sodium fluorescein for assessing the permeability (after the final opacity measurement).

METHODS FOR MEASURED ENDPOINTS:
- Corneal opacity: the opacity of a cornea was measured by the diminution of light passing through the cornea. The light was measured as illuminance by a light meter (opacitometer).
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of microtiter plate reader (OD490)

SCORING SYSTEM: In Vitro Irritancy Score (IVIS)

DECISION CRITERIA:
A test substance that induces an IVIS ≤ 3 is not classified for eye irritancy (UN GHS: no category);
A test substance that induces IVIS >55 is defined as a corrosive or severe irritant (UN GHS: category 1);
For a test substance that induces an IVIS >3 and ≤55, no prediction on irritant potency can be made.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Run / experiment:

Mean of 3 replicates

Value:

-0.1

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

Individual IVIS of test item replicates were 0.5, 0.6 and -1.6.
IVIS scores of positive and negative controls ranged from 1.0 to 2.9 and from 48.1 to 62.1, respectively.

OTHER EFFECTS:
A pH effect of the test item was observed on the rinsing medium, therefore the corneas were rinsed until no color change of the medium was observed.

DEMONSTRATION OF TECHNICAL PROFICIENCY: ethanol was used as a positive control and indicated that the test system was accurate and reliable.

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes, results were within historical range
- Acceptance criteria met for positive control: yes, results were within historical range

Any other information on results incl. tables

Table 1 Historical control data for the BCOP studies

	Negative control			Positive control
	Opacity	Permeability	In vitro Irritancy Score	In vitro Irritancy Score
Range	-2.9 – 3.0	-0.016 – 0.042	-2.8 – 3.0	35.8-77.0
Mean	0.20	0.01	0.32	57.55
SD	1.02	0.01	1.10	12.12
n	63	59	57	38

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the outcome of a Bovine Corneal Opacity and Permeability test (BCOP), performed according to OECD guideline and GLP principles, it is concluded that no classification for eye irritancy is required for DDDA TEA salt (based on IVIS scores < 3 after 10 minutes of treatment).