4,4'-bis(diethylamino)benzophenone

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vitro

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08 March 2018 - 30 March 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 442D (In Vitro Skin Sensitisation: ARE-Nrf2 Luciferase Test Method)

Version / remarks:

adopted February, 2015

Deviations:

no

GLP compliance:

yes

Type of study:

activation of keratinocytes

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-bis(diethylamino)benzophenone

EC Number:

202-025-4

EC Name:

4,4'-bis(diethylamino)benzophenone

Cas Number:

90-93-7

Molecular formula:

C21H28N2O

IUPAC Name:

4-[4-(diethylamino)benzoyl]-N,N-diethylaniline

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch No.of test material: 171116

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature protected from light

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Dissolved in DMSO

Results and discussion

Positive control results:

EC1.5 of the positive control was between 5 and 125 µM (61 µM and 98 µM in experiment 1 and 2, respectively). A dose response was observed and the induction at 250 µM was higher than 2-fold (2.75-fold and 2.72-fold in experiment 1 and 2, respectively).

In vitro / in chemico

Results

Results 1

Key result

Run / experiment:

other: Experiment 1

Parameter:

other: Imax

Value:

5.98

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

positive indication of skin sensitisation

Results 2

Key result

Run / experiment:

other: Experiment 2

Parameter:

other: Imax

Value:

5.05

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Remarks on result:

positive indication of skin sensitisation

Other effects / acceptance of results:

The luciferase activity induction obtained with the positive control, Ethylene dimethacrylate glycol, was above the threshold of 1.5-fold in at least one concentration.
The EC1.5 of the positive control was between 5 and 125 µM (61 µM and 98 µM in experiment 1 and 2, respectively). A dose response was observed and the induction at 250 µM was higher than 2-fold (2.75-fold and 2.72-fold in experiment 1 and 2, respectively).
The average coefficient of variation of the luminescence reading for the vehicle (negative) control DMSO was below 20% (8.8% and 14% in experiment 1 and 2, respectively).

Any other information on results incl. tables

Overview EC_1.5, I_max, IC₃₀and IC₅₀Values

	EC1.5(µM)	Imax	IC30(µM)	IC50(µM)
Test item Experiment 1	<0.98	5.98	3.6	5.4
Test item Experiment 2	<0.49	5.05	4.1	6.8
Pos Control Experiment 1	61	2.75	N/A	N/A
Pos Control Experiment 2	98	2.72	N/A	N/A

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

In conclusion, the substance is classified as positive (activation of the antioxidant/electrophile responsive element (ARE)-dependent pathway in keratinocytes) under the experimental conditions described.

Executive summary:

The ability of the substance to activate the antioxidant/electrophile responsive element (ARE)-dependent pathway was evaluated in the in vitro KeratinoSens assay. Two independent experiments were performed. 4,4’-Bis(diethylamino)benzophenone showed toxicity (IC₃₀values of 3.6µM and 4.1µM and IC₅₀values of 5.4µM and 6.8 µM in experiment 1 and 2, respectively). A biologically relevant, dose-related induction of the luciferase activity (EC_1.5values of < 0.98µM and < 0.49µM in experiment 1 and 2, respectively) was measured in both experiments. The maximum luciferase activity induction (I_max) was 5.98-fold and 5.05-fold in experiment 1 and 2 respectively. The substance is positive in the KeratinoSens^TMassay since positive results (>1.5-fold induction) were observed at test concentrations < 1000µM with a cell viability of >70% compared to the vehicle control.