1,4-diethylbenzene

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Validated in-vitro study, GLP compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.46 (In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1,4-diethylbenzene

EC Number:

203-265-2

EC Name:

1,4-diethylbenzene

Cas Number:

105-05-5

Molecular formula:

C10H14

IUPAC Name:

1,4-diethylbenzene

Test material form:

other: liquid

Details on test material:

purity: 99.3%

Test animals

Species:

other: reconstructed human epidermis model

Strain:

other: EST 1000

Details on test animals or test system and environmental conditions:

Skin model: Batch no. EST-121112-001; CellSytems® Biotechnology GmbH, 53562 Katharinen, Germany

Test system

Amount / concentration applied:

30 µL 1,4-Diethylbenzene were applied to the skin model with a surface area of 0.6 cm2 to uniformly cover the skin surface

Duration of treatment / exposure:

The models were cultivated at 21°C for 20 minutes according to the instructions of the EST1000 supplier CellSystems®. An incubation time with the test item for 20 minutes was recommended by the European Centre for the Validation of Alternative Methods (ECVAM).

Observation period:

Post-treatment incubation period of the rinsed tissues in fresh medium of 42-hours.

Number of animals:

Three replicate tissues were employed

Details on study design:

Concurrent negative and positive controls were used, each in triplicate, to demonstrate that viability (NC), barrier function and resulting issue sensitivity (PC) of the tissues are within a defined historical acceptance range. For the negative control the same dose volume as the test item was used, i.e. 30 µL. The PC item was 5% aqueous sodium dodecyl sulphate (SDS) and was applied to the skin at a volume of 30 µL. The NC item was phosphate buffered saline (PBS)3

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

other: other: % exticntion compared to control

Value:

12.2

Remarks on result:

other:

Remarks:

Basis: mean. Reversibility: no data. Remarks: Test item. (migrated information)

Results 2

Irritation / corrosion parameter:

other: other: % extinction compared to the control

Value:

0

Remarks on result:

other:

Remarks:

Basis: mean. Reversibility: no data. Remarks: Negative control: phosphate buffered saline. (migrated information)

Results 3

Irritation / corrosion parameter:

other: other: % extinction compared to the control

Value:

2.3

Remarks on result:

other:

Remarks:

Basis: mean. Reversibility: no data. Remarks: Positive control 5% aqueous sodium dodecy sulphate. (migrated information)

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant)

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item was considered to be cytotoxic and is predicted to be irritant to skin in accordance with UN GHS category 2.
This Test Guideline used provides an in vitro procedure that may be used for the hazard identification of irritant chemicals (substances and mixtures) in accordance with UN GHS and EU CLP Category 2

Executive summary:

The cell viabilitywas measured by determining theoptical density (OD) at a wavelength of 540 nm. An exposure time of 20 minutes was employed.

The test item, 1,4-Diethylbenzene,was applied to the model skin surface. Water for injection was used as the negative control. 5% aqueous sodium dodecyl sulphate (SDS)was used as the positive reference item. The mean viability of the cells exposed to the test item was 12.2% of the mean negative controls and, hence, below the 50% cut-off value. The test item was considered to be cytotoxic and is predicted to be irritant to skin in accordance with UN GHS category 2.The viability of cells treated with the positive reference item, 5% SDS, was 2.3% of the negative controls and below the 50% cut-off value. Hence, 5% SDS is predicted to cause pronounced skin irritation. All quality criteria required were fulfilled.