3,3'-[methylenebis(oxymethylene)]bisheptane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2008-04-29 to 2008-05-02

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP lab following OECD guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 431 (In vitro skin corrosion: Human Skin Model Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

3,3'-[methylenebis(oxymethylene)]bisheptane

EC Number:

244-815-1

EC Name:

3,3'-[methylenebis(oxymethylene)]bisheptane

Cas Number:

22174-70-5

Molecular formula:

C17H36O2

IUPAC Name:

3,3'-[methylenebis(oxymethylene)]diheptane

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): 2-ethylhexylal
- Physical state: liquid
- Analytical purity: 99.82%
- Lot/batch No.: 0803181500
- Expiration date of the lot/batch: 2009-03-18
- Storage condition of test material: room temperature

Test animals

Species:

human

Strain:

other: Episkin Standard Model

Test system

Type of coverage:

open

Vehicle:

unchanged (no vehicle)

Controls:

not required

Duration of treatment / exposure:

3, 60 and 240 minutes

Observation period:

3 hours after end of exposure

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: other: Cell Viability

Value:

> 35

Remarks on result:

other:

Remarks:

Basis: mean. Time point: 240 minutes. Reversibility: no data. Remarks: Following OECD Guideline 431: the cell viability is never below 35% even after 4 hours exposure. (migrated information)

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Remarks:

Migrated information: non corrosive

Conclusions:

According to the obtained results (cell viability never below 35% for tested exposure time) and reporting to the UN and EU classification criterias for corrosive chemical categorisation, we can conclude that the organic solvent 2-ethylhexylal can be classified as non corrosive.

Executive summary:

The objective of this study is to predict and classify the skin corrositivity potential of the chemical product 2-ethylhexylal according to chemical safety regulation, by assessment of its effect on a reconstructed human epidermis.

The principle of this test is based on the experience that corrosive chemicals show cytotoxic effect following short-term exposure on the stratum corneum of the epidermis. The test protocol does not provide adequate information on skin irritation. The assay was conducted according to the OECD guideline n° 431 "In vitro skin corrosion: Human Skin Model Test".

The Episkin is a highly differentiated and stratified epidermis validated model comprising the main basal, supra basal, spinous and granular layers and a functional stratum corneum obtained after a culture period. Its use for skin corrositivity testing involves topical application of the test material to the surface of the epidermis, and the subsequent assessment of its effects on cell viability.

The selected positive and negative reference chemicals are phosphate buffer saline and acetic acid glacial.

Corrositivity potential of 2-ethylhexylal involved topical application of test item to the surface of the reconstructed human epidermis and the subsequent assessment of its effect on cell viability. 10µl of the test item was applied topically to the epidermal model for 3, 60 and 240 minutes (3 epidermis units were used per test material, 2 for positive and 1 for negative controls and time exposure). At the end of the treatment, all residual test item and chemical controls were removed by thoroughly rinsing epidermis units with 25 ml of sterile phosphate buffered saline solution. The resulting cell viability was further assessed by incubating tissues for 3 hours at 37°C, 5% CO2 atmosphere with MTT (0.3 mg/ml) in assay medium. The basis of this test is that viable cells metabolize MTT into intra-cellular formazan crystals. The precipitated formazan was finally extracted using acidified isopropanol and quantified spectrophotometrically at 550 nm by comparison to a blank (acidified propanol).

According to the obtained results (cell viability never below 35% for tested exposure time) and reporting to the UN and EU classification criteria for corrosive chemical categorization, we can conclude that the organic solvent 2-ethylhexylal can be classified as non corrosive (OECD 431: non-corrosive to skin if the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%).