Ibuprofen

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 431 (In Vitro Skin Corrosion: Human Skin Model Test)

Version / remarks:

13 April 2004

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EU Method B: Methods for the determination of toxicity and other health effects: In Vitro Skin Corrosion: Human Skin Model Test; Official Journal of the European Union, No. L 142

Test guideline 3

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

24 April 2002; for determination of a corrosive/irritant property

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ibuprofen

EC Number:

239-784-6

EC Name:

Ibuprofen

Cas Number:

15687-27-1

Molecular formula:

C13H18O2

IUPAC Name:

2-(4-isobutylphenyl)propanoic acid

Test material form:

solid

Specific details on test material used for the study:

- Name of test substance: Ibuprofen
- Test substance No.: 02/0156-6
- Batch ID: IB1S1290
- Purity: 99.7%
- pH: ca. 4.5 (undiluted test substance, moistened with water)

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

other: EpiDerm™ human epidermis model

Justification for test system used:

Based on the results of ECVAM (European Center for Validation of Alternative Methods) funded validation studies, it was concluded by the ECVAM Scientific Advisory Committee that the EpiDerm™ human epidermis model is suitable to be used for distinguishing between corrosive and non-corrosive chemicals (ECVAM: ESAC statement on the application of the EpiDerm™ human skin model for skin corrosivity testing of 14-15 Mar 2000) as well as between irritant and non-irritant chemicals (ECVAM: ESAC statement on the scientific validity of in-vitro tests for skin irritation testing of 5 Nov 2008).

Vehicle:

unchanged (no vehicle)

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: The EpiDerm™ model consists of normal, human-derived epidermal keratinocytes which have been cultured to form a multi layered, highly differentiated model of the humanepidermis. It consists of organized basal, spinous and granular layers, and a multi-layered stratum corneum containing intercellular lamellar lipid layers arranged in patterns analogous to those found in vivo. The EpiDerm™ tissues (surface 0.6 cm²) are cultured on specially prepared cell culture inserts (MILLICELLs®, 10 mm Ø) and commercially available as kits (EpiDerm™ 200), containing 24 tissues on shipping agarose.
- Origin: MatTek Corporation, Ashland MA, USA

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: room temperature (3 min exposure) and 37°C (1 hour exposure)

REMOVAL OF TEST MATERIAL AND CONTROLS
The tissues were washed with PBS to remove residual test material 3 minutes or 1 hour after start of the application treatment. Rinsed tissues were kept in 24-well plates (holding plates) at room temperature on assay medium until all tissues per application time were dosed and rinsed.

VIABILITY TEST
The assay medium was replaced by MTT solution and tissues were incubated for 3 hours. After incubation, tissues were washed with PBS and the formazan produced by the tissues was extracted with isopropanol over night at room temperature. The optical density at a wavelength of 570 nm (OD570) of the extracts was determined spectrophotometrically. Blank values were established of 6 microtiter wells filled with isopropanol for each microtiter plate.

Control samples:

yes, concurrent vehicle

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied: 25 µL of highly de-ionized water was applied first. Thereafter, a bulk volume of 25 µL of test material was applied with a sharp spoon and homogeneously distributed with water

VEHICLE CONTROL
- Amount(s) applied: 50 µL

POSITIVE CONTROL
- Amount(s) applied: 50 µL

Duration of treatment / exposure:

3 minutes and 1 hour

Number of replicates:

2

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

3 minutes exposure

Value:

106

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

1 hour exposure

Value:

99

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

other: Not corrosive