Phosphoric acid, mono- and di-isotridecyl esters, compd. with 2,2'-iminobis[ethanol]

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 September 12, 2016 to September 19, 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

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:

yes

Remarks:

but the study integrity was not adversely affected by the deviations

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

but the study integrity was not adversely affected by the deviations

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Phosphoric acid, mono- and di-isotridecyl esters, compd. with 2,2'-iminobis [ethanol]

Cas Number:

85409-75-2

IUPAC Name:

Phosphoric acid, mono- and di-isotridecyl esters, compd. with 2,2'-iminobis [ethanol]

Constituent 2

Reference substance name:

Bis(2-hydroxyethyl)ammonium dihydrogen phosphate

EC Number:

249-913-8

EC Name:

Bis(2-hydroxyethyl)ammonium dihydrogen phosphate

Cas Number:

29870-32-4

Molecular formula:

C4H11NO2.xH3O4P

IUPAC Name:

bis(2-hydroxyethyl)ammonium dihydrogen phosphate

Constituent 3

Reference substance name:

bis(2-hydroxyethyl)ammonium diphosphate

IUPAC Name:

bis(2-hydroxyethyl)ammonium diphosphate

Constituent 4

Reference substance name:

Water

EC Number:

231-791-2

EC Name:

Water

Cas Number:

7732-18-5

Molecular formula:

H2O

IUPAC Name:

Dihydrogen oxide

Test material form:

other: highly viscous liquid

Details on test material:

- Name of test material (as cited in study report): Phosphoric acid, mono- and di-isotridecyl esters, compd. with 2,2'-iminobis [ethanol]
- ZS name: PHOSPHORSÄUREPARTIALESTER, DEASALZ I-C13
- ZS number: 1577
- Batch: RE 10-7
- Appearance, Color: Colorless, highly viscous liquid

Specific details on test material used for the study:

Batch no.: RE 10-7
Purity/composition: 10% dry matter
Appearance: withish liquid

In vitro test system

Test system:

human skin model

Remarks:

human three dimensional epidermal model (EPISKIN Small Model (EPISKIN-SMTM))

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

The test is based on the experience that irritant chemicals show cytotoxic effects following short term exposure to the stratum corneum of the epidermis. The test was designed to predict and classify the skin irritation potential of a test substance by assessment of its effect on a three dimensional human epidermis model. In the interest of sound science and animal welfare, a sequential testing strategy is recommended to minimise the need of in vivo testing. One of the validated in vitro skin irritation tests is the EPISKIN test, which is recommended in international guidelines (e.g. OECD and EC).

Vehicle:

unchanged (no vehicle)

Details on test system:

The test substance was applied undiluted (25 µl) directly on top of the skin tissue for 15 ± 0.5 minutes. After a 42 hour post-incubation period, determination of the cytotoxic (irritancy) effect was performed. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

25 µL

Duration of treatment / exposure:

15 min

Duration of post-treatment incubation (if applicable):

42 h

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Reduction of MTT to MTT formazan

Value:

78

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

Skin irritation was expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 15 ± 0.5 minutes treatment with the test substance compared to the negative control tissues was 78%. Since it was above 50% after 15 ± 0.5 minutes treatment the test substance was considered to be non-irritant. The positive control had a mean cell viability of 15% after 15 ± 0.5 minutes exposure. The absolute mean OD570 (optical density at 570 nm) of the negative control tissues was within the laboratory historical control data range. The standard deviation value of the percentage viability of three tissues treated identically with the reference items was less than 13%, indicating that the test system functioned properly.
It was concluded that this test was valid and that the test substance was non-irritant in the in vitro skin irritation test under the experimental conditions described in this report.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the study conditions, the substance was considered to be non-irritant to human skin.

Executive summary:

A study was conducted to determine the in vitro skin irritation potential of the substance according to OECD Guideline 439 and EU Method B.46, in compliance with GLP. Human three dimensional epidermal tissue model was exposed in triplicate to at least 25 µL test substance for 15 min. After a 42 h post-incubation period, a determination of the cytotoxic (irritancy) effect was performed. Cytotoxicity was expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT at the end of the treatment. Skin irritation was expressed as the remaining cell viability after exposure to the test substance. The relative mean tissue viability obtained after 15 ± 0.5 min treatment with the test substance compared to the negative control tissues was 78%. Since it was above 50% the test substance was considered to be non-irritant. The positive control showed a mean cell viability of 15% after 15 ± 0.5 min exposure. The absolute mean OD570 (optical density at 570 nm) of the negative control tissues was within the laboratory historical control data range. The standard deviation value of the percentage viability of three tissues treated identically with the reference substance was less than 13%, indicating that the test system functioned properly. Under the study conditions, the substance was considered to be non-irritant to human skin (Verbaan, 2016).