Reaction product of 6H-dibenz[c,e][1,2]oxaphosphorin 6-oxide, itaconic acid and ethylene glycol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-12-23 - 2017-02-08

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Bis(2-hydroxyethyl) (6H-dibenz[c,e][1,2]oxaphosphorin-6-ylmethyl)succinate P-oxide

EC Number:

264-313-6

EC Name:

Bis(2-hydroxyethyl) (6H-dibenz[c,e][1,2]oxaphosphorin-6-ylmethyl)succinate P-oxide

Cas Number:

63562-34-5

Molecular formula:

C21H23O8P

IUPAC Name:

Butanedioic acid, 2-​[(6-​oxido-​6H-​dibenz[c,​e]​[1,​2]​oxaphosphorin-​6-​yl)​methyl]​-​, 1,​4-​bis(2-​hydroxyethyl) ester

Test material form:

semi-solid (amorphous): gel

Details on test material:

purity > 95%

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Details on test system:

As the test item is highly viscous, Ukanol FR 70 was applied to a nylon mesh prior to application to the skin surface. 25 mg of test item were applied to the nylon mesh and incubated at 37°C, 5% CO2 and 95% relative humidity for 60 minutes to test for possible interaction between test substance and the mesh.

Control samples:

yes, concurrent no treatment

yes, concurrent positive control

Amount/concentration applied:

positive control: 30µl
negative control: 30µl
test item: 25 mg on a nylon mesh

Duration of treatment / exposure:

60 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3

Results and discussion

In vitro

Results

Results 1

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

negative control

Value:

100

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Results 2

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

positive control

Value:

7.2

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Results 3

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

test item

Value:

98.3

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the present test conditions, Ukanol FR 70 tested at an exposure time of 60 minutes and a 42-hour post-treatment incubation period, was non-cytotoxic and, hence, predicted to be non-irritant to skin in an experiment employing an artificial three-dimensional model of human skin. Hence, the test item did not show irritant properties and is therefore not classified as irritant (UN GHS no category).

Executive summary:

The purpose of this study was to determine cytotoxic properties of Ukanol FR 70 to skin cells, which might lead to irritation of human skin, by using an artificial three-dimensional model of human skin. The EpiDermTM model was employed.

Three tissues were used for each treatment and concurrent control groups. The optical density (OD) was determined by using the MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide, Thiazolyl blue) reduction assay and expressed as relative percentage of viability of the negative control-treated tissues.

As the test item is highly viscous, Ukanol FR 70 was applied to a nylon mesh prior to application to the skin surface. The nylon mesh loaded with 25 mg of test item was applied to the skin model which was moistened with Dulbecco’s phosphate buffered saline (D-PBS).D-PBS was used as the negative control.5% aqueous sodium dodecyl sulphate (SDS)was used as the positive reference item. An exposure time of 60 minutes was employed followed by a 42-hour post-treatment incubation period in fresh medium. The mean viability of cells exposed to Ukanol FR 70 was 98.3% of the negative controls and, hence, was well above the cut-off percentage cell viability value that distinguishes irritant from non-irritant test items of > 50%. Ukanol FR 70 was considered to be non-cytotoxic and predicted to be non-irritant to skin.

The mean optical density (OD) of 3 negative control tissues was 1.472 and was well within the acceptable range of ≥ 1.0 to ≤ 2.5.The viability of cells treated with the positive reference item, 5% SDS, was 7.2 of the negative control and fulfilled the acceptance criterion of ≤20%.

The standard deviation of all triplicates determined was below the limit of acceptance of 18%.Hence, all acceptance criteria were fulfilled.