Reaction mass of 2-butylheptanoic acid and 2-ethylnonanoic acid and 2-methyldecanoic acid and 2-propyloctanoic acid

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study, category approach

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying Ocular Corrosives and Severe Irritants)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU method B.47 (Bovine corneal opacity and permeability test method for identifying ocular corrosives and severe irritants)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

940-601-3

EC Number:

940-601-3

IUPAC Name:

940-601-3

Constituent 2

Reference substance name:

Reaction mass of n-undecanoic-acid and 2-methyl-decanoic-acid and 2-ethyl-nonanoic-acid and 2-propyl-octanoic-acid and 2-butyl-heptanoic-acid

IUPAC Name:

Reaction mass of n-undecanoic-acid and 2-methyl-decanoic-acid and 2-ethyl-nonanoic-acid and 2-propyl-octanoic-acid and 2-butyl-heptanoic-acid

Details on test material:

- Name of test material (as cited in study report): Reaction mass of n-undecanoic-acid and 2-methyl-decanoic-acid and 2-ethyl-nonanoic-acid and 2-propyl-octanoic-acid and 2-butyl-heptanoic-acid
- Substance type: pure active substance
- Physical state: liquid
- Storage condition of test material: at room temperature (20 ± 5°C), protected from light

Test animals / tissue source

Details on test animals or tissues and environmental conditions:

Fresh bovine eyes were obtained from a slaughterhose (Müller Fleisch GmbH, Birkenfeld, Germany) on the day of the test. The cattle were between 12 and 60 months old. The eyes were transported to the test facility in Hank's balanced salt solution (supplemented with 0.01% streptomycin and 0.01% penicillin). Then the corneas were dissected and incubated in medium at 32 ± 1°C in an incubation chamber for 1 hour.

Test system

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

TEST MATERIAL
- Amounts applied: 750 µl
- Negative Control: Sodium chloride solution: 0.9% NaCl (CAS-No. 7647-14-5), dissolved in deionised water
- Positive Control: Dimethyl formamide, DMF (CAS-No. 68-12-2), undiluted

Duration of treatment / exposure:

10 min

Details on study design:

After having carefully cleaned and sterilised the cornea holders, they were kept in the incubation chamber at 32 °C ± 1 °C. On the day of the assay, the MEM without phenol red was supplemented with sodium bicarbonate, L-glutamine and 1% fetal calf serum (= complete MEM) and stored in a water bath at 32 °C ± 1 °C. The same was performed with the MEM with phenol red. After the arrival of the corneas they were examined and only corneas which were free from defects were used. The corneas were excised with a scalpel and cut from the globe with a 2-3 mm ring of sclera around the outside. Each cornea was transferred to a cornea holder in which pre-warmed cMEM without phenol red was filled. The holders were then incubated for one hour in the incubation chamber at 32 °C ± 1 °C.
After the initial incubation, the medium was changed and the baseline opacity for each cornea was recorded. None of the corneas showed tissue damage; therefore, all corneas were used. The baseline opacity was measured by placing the holder with the cornea in a spectral photometer and recording the absorption at 570 nm. Opacity is calculated from the measured absorption. For each treatment group (negative control solution, test item and positive control), three replicates were used. After removal of the pre-incubation medium, 750 μl negative controlsolution resp. test item resp. positive control were applied to each replicate. According to the characteristics of the test item, the following treatment procedure was performed:
The respective substance (negative control solution, test item or positive control) was applied by pipetting 750 μL of the appropriate solution through the refill hole in the holder on the cornea. The test item was given on the epithelium in such a manner that as much as possible of the cornea was covered with test item. Exposition time on the corneas was 10 min at 32 ± 1 °C. After thorough rinsing with cMEM with phenol red and final rinsing with cMEM without phenol red, the anterior chamber was filled with cMEM without phenol red, and the corneas were stored for an additional two hours at 32 ± 1°C (post-incubation). After the post-incubation, the cMEM without phenol red was renewed in both chambers.Then, final opacity value of each cornea was recorded (again by measurement at 570 nm). The cMEM without phenol red was removed from the front chamber, and 1 mL sodium fluorescein solution (concentration 4 mg/ml) was added to the front chamber. The chambers were then closed again and incubated for 90 ± 5 min at 32 ± 1 C. After incubation, the content of the posterior chamber was thoroughly mixed. Then, the permeability of the liquid was measured with the spectral photometer as optical density at 490 nm.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

other: IVIS test item

Basis:

mean

Score:

5.493

Results 2

Irritation parameter:

other: IVIS negative control

Basis:

mean

Score:

0.187

Results 3

Irritation parameter:

other: IVIS positive control

Basis:

mean

Score:

86.251

Irritant / corrosive response data:

In the negative control, no signs of eye irritation were observed. The positive control induced serious eye damage on the cornea. The test item Reaction mass of n-undecanoic acid and 2-methyldecanoic acid and 2-ethylnonanoic acid and 2-propyloctanoic acid and 2-butylheptanoic acid showed effects on the cornea of the bovine eye. The calculated IVIS (in vitro irritancy score) is 5.493.

Any other information on results incl. tables

Table: IVIS values
Test group	IVIS	Mean IVIS	rel. SD*
Negative control (0.9% NaCl)	0.253	0.187	32.5%
	0.133
	0.177
Test substance	5.221	5.493	16.6%
	6.511
	4.748
Positive control (DMF)	92.102	86.251	22.3%
	101.837
	64.815
* = relative standard deviation

Applicant's summary and conclusion

Interpretation of results:

other: not eye damaging

Remarks:

Criteria used for interpretation of results: OECD GHS

Conclusions:

The test item was tested pure. A mean IVIS of 5.493 was calculated. According to OECD Guideline no. 437 (Jul. 2013), a substance with an IVIS > 3 and ≤ 55 cannot be classified in a UN GHS Category for eye damage with the BCOP test.

Executive summary:

This in vitro study was performed to assess serious eye damage of Reaction mass of n-undecanoic acid and 2-methyldecanoic acid and 2-ethylnonanoic acid and 2-propyloctanoic acid and 2-butylheptanoic acid by quantitative measurements of changes in opacity and permeability in a bovine cornea following OECD Guideline 437 resp. EU Method B.47 and in accordance with the OECD Principles of Good Laboratory Practice.

The test item was brought onto the cornea of a bovine eye which previously had been incubated with cMEM without phenol red at 32 ± 1 °C for one hour and whose opacity had been determined. The test item was incubated on the cornea for 10 minutes at 32 ± 1 °C. After removal of the test item and two hours post-incubation, opacity and permeability values were measured.

Physiological sodium chloride solution was used as negative control, undiluted dimethyl formamide was used as positive control.

The positive control induced serious eye damage on the cornea, mean IVIS was 86.251. The negative control showed no irritation effects and no serious eye damage, mean IVIS was 0.187.

The test item was tested pure. A mean IVIS of 5.493 was calculated. According to OECD Guideline no. 437 (Jul. 2013), a substance with an IVIS > 3 and ≤ 55 cannot be classified in a UN GHS Category for eye damage with the BCOP test.

No observations were made which might cause doubts concerning the validity of the study outcome. The test is considered valid.