Tall oil, polymd., oxidized

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

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)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Test material

Test material information

1

Reference substance name:

Tall oil, polymd., oxidized

EC Number:

683-326-1

Cas Number:

68815-17-8

Molecular formula:

Not applicable (UVCB substance)

IUPAC Name:

Tall oil, polymd., oxidized

Test material form:

liquid

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

This test uses the EPISKIN-SM™ reconstructed human epidermis model (SkinEthic) which consists of normal human epidermal keratinocytes (NHEK) and therefore represents in vitro the target organ of the species of interest and closely mimics the biochemical and physiological properties of the upper parts of the human skin, i.e. the epidermis.

Vehicle:

unchanged (no vehicle)

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

The test item was applied undiluted. 10 μL (26.3 μL/cm2) of the test item was dispensed directly atop the tissue.

Duration of treatment / exposure:

15 ± 0.5 minutes.

Duration of post-treatment incubation (if applicable):

42 ± 1 hours.

Number of replicates:

The test was performed on a total of 3 tissues per dose group.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

ca. 32.8

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

In this study under the given conditions the test item showed irritant effects. The relative mean tissue viability after 15 min of exposure and 42 h post-incubation was ≤ 50%. The test item is therefore classified as “irritant” in accordance with UN GHS “Category 2”.

Executive summary:

In the present study the skin irritant potential of Tall oil, polym., oxidized was analysed. The EPISKIN-Standard Model™ (EPISKIN-SMTM), a reconstituted three-dimensional human epidermis model, was used as a replacement for the Draize Skin Irritation Test (OECD TG 404) to distinguish between UN GHS “Category 2” skin irritating test substances and not categorized test substances (“No Category”) which may be considered as non-irritant. Hereby, the test item was applied topically. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT after a 15 min exposure and 42 h post-incubation period and compared to those of the concurrent negative controls.

The test item showed no non-specific MTT-reducing but colouring potential in the range of 570 ± 30 nm. Therefore, additional viable tissue controls were treated with the test item to determine the non-specific colour (NSCliving). NSCliving was > 5% and ≤ 30% (15.4%) relative to the negative control of living epidermis. Therefore, correction of the results was necessary.

The test item showed irritant effects. The mean relative tissue viability (% negative control) was ≤ 50% (32.8%, after correction for NSCliving 17.5%) after 15 min treatment and 42°h post-incubation.