4-phenylbenzophenone

Endpoint summary

Description of key information

In a reliable in vitro skin corrosion study human skin tissue (epidermis keratinocytes) was exposed to undiluted substance for 3-minutes and 1-hour. There was 99% and 94% tissue viability following the 3-minutes and 1-hour exposure points, respectively. Resultantly, the substance is considered to be a non-irritant and non-corrosive to skin.

In a reliable in vitro skin irritation study human skin tissue (epidermis keratinocytes) was exposed to the undiluted substance for 15-minutes. There was 109% tissue viability following the 15-minute exposure point. Resultantly, the substance is considered to be a non-irritant to skin.

In a reliable in vitro eye corrosion/irritation study isolated bovine cornea was exposed to neat substance for 240-minutes. The mean in vitro irritancy score was -2.8 and resultantly, the substance is considered to be a non-irritant to the eye.

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:

11 Jul 2017 - 14 Jul 2017

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)

Version / remarks:

Adopted 29 July 2016

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EC Guideline No. 440/2008

Version / remarks:

Part B: Methods for the Determination of Toxicity and other health effects, Guideline B.40 BIS: "In Vitro Skin Corrosion: Human Skin Model Test". Official Journal of the European Union No. L142, 31 May 2008.

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch No.of test material: 20161118
- Expiration date of the lot/batch: 17 November 2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature protected from light
- Stability under test conditions: Yes, maximum temperature: 90°C

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

Recommended test system in international guidelines (OECD and EC).

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: EpiDerm Skin Model
- Tissue batch number(s): 26490

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: All incubations, with the exception of the test item incubation of 3 minutes at room temperature, were carried out at 37.0 ± 1.0°C.

NUMBER OF REPLICATE TISSUES: 2

PREDICTION MODEL / DECISION CRITERIA (choose relevant statement)
- The test substance is considered to be corrosive to skin if [complete, e.g. 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%.]

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 3-minute exposure: 34.1 mg; 1-minute exposure: 41.2 mg??

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 50 µl

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 50 µl
- Concentration (if solution): 8N

Duration of treatment / exposure:

3- minutes and 1-hour

Number of replicates:

Two tissues per timepoint.

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3-minute

Value:

99

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

1-hour

Value:

94

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes
- Range of historical values if different from the ones specified in the test guideline: yes

Mean Absorption in the in vitro Skin Corrosion Test

	3 -minute application				1 -hour application
	A (OD570)	B (OD570)	Mean (OD570)	SD	A (OD570)	B (OD570)	Mean (OD570)	SD
Negative control	1.622	1.712	1.667	± 0.063	1.666	1.821	1.744	± 0.11
Substance	1.587	1.711	1.649	± 0.088	1.603	1.658	1.630	± 0.039
Positive control	0.114	0.109	0.112	± 0.004	0.18	0.155	0.168	± 0.018

Interpretation of results:

GHS criteria not met

Conclusions:

The substance is not corrosive in the in vitro skin corrosion test under the experimental conditions described.

Executive summary:

In an in vitro skin corrosion study human skin tissue (epidermal keratinocytes) was exposed to undiluted substance for 3-minutes and 1-hour. There was 99% and 94% tissue viability following the 3-minutes and 1-hour exposure points, respectively. Resultantly, the test material is considered to be a non-irritant and non-corrosive to skin.

Reference 2

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9 August 2017 - 14 August 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 439 (In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method)

Version / remarks:

28 July 2015

Deviations:

yes

Remarks:

The EpiSkin supplier adviced to transfer the Episkin tissues in the 12-well plates to maintenance medium for at least 2 hours instead of 24 hours. Since all acceptability criteria were met this has no adverse effect on the study integrity.

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch No.of test material: 20161118
- Expiration date of the lot/batch: 17 November 2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Use amber glassware or wrap container in aluminum-foil; At room temperature protected from light

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

Validated in vitro skin irritation model.

Vehicle:

unchanged (no vehicle)

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

10.2 to 22.1 mg

Duration of treatment / exposure:

15 ± 0.5 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3 tissues per test item (triplicate)

Irritation / corrosion parameter:

% tissue viability

Value:

109

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

The positive control had a mean cell viability after 15 ± 0.5 minutes exposure of 4.8%. The absolute mean OD570 of the negative control tissues was within the laboratory historical control data range. The standard deviation value of the percentage viability of three tissues treated identically was ≤ 3%, indicating that the test system functioned properly.

	Mean tissue viability (percentage of control)	Standard deviation (percentage)
Negative control	100	1.3
Omnirad 4-PBZ	109	2.1
Positive control	4.8	2.3

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, the substance is non-irritant in the in vitro skin irritation test under the experimental conditions described and should not be classified according to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) of the United Nations.

Executive summary:

The potential for the substance to cause skin irritation was evaluated employing an in vitro human three dimensional epidermal model (EPISKIN Small model (EPISKIN-SM^TM)). The design of this study was based on the OECD Guideline 439. In vitro Skin Irritation: Reconstructed Human Epidermis Test Method, (adopted 28 July 2015). The possible skin irritation potential of the substance was tested through topical application for 15 minutes. Cytotoxicity (irritancy) is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment.Skin irritation is expressed as the remaining cell viability after exposure to the substance. The relative mean tissue viability obtained after 15 ± 0.5 minutes treatment with the substance compared to the negative control tissues was 109%.  Therefore,the substance is considered to be a non-irritant.

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:

19 Jun 2017 - 20 Jun 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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:

July 26, 2013

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and batch No.of test material: Sponsor and 20161118
- Expiration date of the batch: 17 November 2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature protected from light
- Solubility and stability of the test substance in the solvent/vehicle: Not soluble in physiological saline

FORM AS APPLIED IN THE TEST (if different from that of starting material): Since no workable suspension of Omnirad 4-PBZ in physiological saline could be obtained, the test item was used as delivered by the sponsor and added pure on top of the corneas.

Species:

cattle

Strain:

not specified

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

Since no workable suspension of the substance in physiological saline could be obtained, the substance was used as delivered by the sponsor and added pure on top of the corneas (318.12 to 327.82 mg).

Duration of treatment / exposure:

240 ± 10 minutes

Duration of post- treatment incubation (in vitro):

None.

Number of animals or in vitro replicates:

Triplicate.

Details on study design:

SELECTION AND PREPARATION OF CORNEAS

QUALITY CHECK OF THE ISOLATED CORNEAS
The eyes were checked for unacceptable defects, such as opacity, scratches, pigmentation and neovascularization by removing them from the physiological saline and holding them in the light. Those exhibiting defects were discarded.

TREATMENT METHOD: open chamber

POST-INCUBATION PERIOD: no.

REMOVAL OF TEST SUBSTANCE
- Number of washing steps after exposure period: three washing steps

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 (I = luminous flux per area, unit: lux) by a light meter.
- Corneal permeability: passage of sodium fluorescein dye measured with the aid of [UV/VIS spectrophotometry / microtiter plate reader] (OD490). After the incubation period, the medium in the posterior compartment of each holder was removed and placed into a sampling tube labelled according to holder number. 360 µl of the medium from each sampling tube was transferred to a 96-well plate. The optical density at 490 nm (OD490) of each sampling tube was measured in triplicate using a microplate reader (TECAN Infinite® M200 Pro Plate Reader).

SCORING SYSTEM: In Vitro Irritancy Score (IVIS) = mean opacity value + (15 x mean OD490 value)

DECISION CRITERIA: please specify if the decision criteria as indicated in the TG was used:

IVIS range UN GHS
≤ 3 No Category
> 3; ≤ 55 No prediction can be made
>55 Category 1

Irritation parameter:

cornea opacity score

Value:

-3.5

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Irritation parameter:

fluorescein retention score

Value:

0.045

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Irritation parameter:

in vitro irritation score

Value:

-2.8

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Treatment	Mean Opacity	Mean Permeability	Mean In vitro Irritation Score
Negative control	3.4	0.021	3.7
Positive control	108	2.328	143
Substance	-3.5	0.045	-2.8

Interpretation of results:

GHS criteria not met

Conclusions:

The substance did not induce ocular irritation.

Executive summary:

In an in vitro eye corrosion/irritation study isolated bovine cornea was exposed to neat substance for 240-minutes. The mean in vitro irritancy score was -2.8 and resultantly, the substance is considered to be a non-irritant to the eye.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the findings of reliable in vitro studies, classification of the substance is not justified.