Carbonic acid, C,C'-[4-(2-bromoacetyl)-1,3-phenylene] C,C'-dimethyl ester

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17.07.2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-(2-bromoacetyl)-3-[(methoxycarbonyl)oxy]phenyl methyl carbonate

EC Number:

807-596-9

Cas Number:

1428451-07-3

Molecular formula:

C12H11BrO7

IUPAC Name:

4-(2-bromoacetyl)-3-[(methoxycarbonyl)oxy]phenyl methyl carbonate

Test material form:

solid: bulk

Test animals / tissue source

Species:

cattle

Test system

Controls:

yes, concurrent positive control

yes, concurrent negative control

Duration of treatment / exposure:

240 min

Number of animals or in vitro replicates:

3

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Value:

ca. 2.72

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Any other information on results incl. tables

Opacity:

The change of opacity value of each treated cornea or positive and negative control corneae was calculated by subtracting the initial basal opacity from the post treatment opacity reading (t240 – t0), for each individual cornea. The average change in opacity of the negative control corneae was calculated and this value was subtracted from the change in opacity of each treated cornea or positive control to obtain a corrected opacity.

Permeability:

The corrected OD490 value of each cornea treated with positive control and test item was calculated by subtracting the average negative control cornea value from the original permeability value for each cornea.

IVIS Calculation:

The following formula was used to determine the IVIS of the negative control: IVIS = opacity value + (15 x OD490 value) The following formula was used to determine the IVIS of the positive control and the test item: IVIS = (opacity value – opacity value mean negative control) + (15 x corrected OD490 value) The mean IVIS value of each treated group was calculated from the IVIS values. Depending on the score obtained, the test item was classified into the following category according to OECD guideline 437:

IVIS	In vitro Irritancy Score (according to OECD 437)
<= 3	No Category (according to GHS)
> 3; <= 55	No prediction can be made
> 55	Serious eye damage according to CLP/EPA/GHS (Cat 1)

The test is acceptable because

• the positive control gives an IVIS that falls within two standard deviations of the current historical mean (updated every three months), and because

• the negative control responses result in opacity and permeability values that are less than the established upper limits for background opacity and permeability values for bovine corneae treated with the respective negative control.

Discussion

After a first opacity measurement of the fresh bovine corneae (t0), the 20% (w/v) suspension in saline of the test item 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone, the positive, and the negative controls were applied to corneae and incubated for 240 minutes at 32 ± 1 °C. After the incubation phase the test item, the positive, and the negative controls were each rinsed from the corneae and opacity was measured again (t240). After the opacity measurements permeability of the corneae was determined by measuring spectrophotometrically the transfer of sodium fluorescein after incubation in a horizontal position for 90 minutes at 32 ± 1 °C. With the negative control (saline) neither an increase of opacity nor permeability of the corneae could be observed (mean IVIS = 1.04). The positive control (10% (w/v) Benzalkonium chloride in saline) showed clear opacity and distinctive permeability of the corneae (mean IVIS = 128.43) corresponding to a classification as serious eye damaging (CLP/EPA/GHS (Cat 1)). The mean IVIS of the positive control (mean IVIS = 128.43) was in the range of the historical data (mean IVIS 116.24 ± 2 * 9.31 (see Fig. 3)). Relative to the negative control, the test item 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone caused an increase of the corneal opacity but not of the permeability. The calculated mean IVIS was 2.72 (threshold for serious eye damage: IVIS ≥ 55). According to OECD 437 the test item is not categorized.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, according to the current study and under the experimental conditions reported, 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone is not irritating to eyes.

Executive summary:

An in vitro study was performed to assess the corneal damage potential of 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone by means of the BCOP assay according to OECD 437 using fresh bovine corneae.

After a first opacity measurement of the fresh bovine corneae (t0), the 20% (w/v) suspension in saline (0.9% (w/v) NaCl in deionised water) of the test item 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone, the positive, and the negative controls were applied to corneae fixed in an incubation chamber in horizontal position and incubated for 240 minutes at 32 ± 1 °C. The posterior chamber contained incubation medium. After the incubation phase the test item, the positive, and the negative controls were each rinsed from the corneae and opacity was measured again (t240). After the opacity measurements permeability of the corneae was determined by measuring spectrophotometrically the transfer of sodium fluorescein after incubation in a horizontal position for 90 minutes at 32 ± 1 °C. With the negative control (physiological saline) neither an increase of opacity nor permeability of the corneae could be observed. The positive control (10% (w/v) Benzalkonium chloride in saline) showed clear opacity and distinctive permeability of the corneae corresponding to a classification as serious eye damage (CLP/EPA/GHS (Cat 1)). Relative to the negative control, the test item 2’,4’-Bis(methoxycarbonyloxy)-2-brom-acetophenone an increase of the corneal opacity but not of the permeability compared with the values caused by the negative control. The calculated mean in vitro irritancy score was 2.72. According to OECD 437 the test item is not irritating to eyes.