Disodium naphthalene-1,5-disulphonate

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

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)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Disodium naphthalene-1,5-disulphonate

EC Number:

216-732-0

EC Name:

Disodium naphthalene-1,5-disulphonate

Cas Number:

1655-29-4

Molecular formula:

C10H8O6S2.2Na

IUPAC Name:

disodium naphthalene-1,5-disulphonate

impurity 1

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:

solid: crystalline

Details on test material:

Test item: Armstrongsäure-di-Natriumsalz Monohydrat
CAS name: 1,5-Naphthalenedisulfonic acid, sodium salt (1 :2) Monohydrat
CAS number: 207569-02-6
Empirical formula: C10 H6 O6 S2 * 2Na * H2O
Molecular mass: 350.3 g/mol
Batch number: CHNHFC1602
Content monohydrat-form: 99.8 %
Corresponds to 94,7 % anhydrous form, CAS: 1655-29-4

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Justification for test system used:

Commercially available test system

Vehicle:

physiological saline

Details on test system:

RECONSTRUCTED HUMAN EPIDERMIS (RHE) TISSUE
- Model used: epiCS® (CellSystems, Troisdorf, Germany).
- Tissue batch number(s): Cat.-No.CS-1001
- Date of initiation of testing: 25 Nov 2015
TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: incubator (37 ± 2° C) for 20 min- exposure
- Temperature of post-treatment incubation (if applicable): 37 ± 2° C
MTT DYE USED TO MEASURE TISSUE VIABILITY AFTER TREATMENT / EXPOSURE
- MTT concentration: 1mg/ml
- Incubation time: 3 hours
- Spectrophotometer: EL808, Bio-Tek
- Wavelength: 570 nm
NUMBER OF INDEPENDENT TESTING RUNS / EXPERIMENTS TO DERIVE FINAL PREDICTION:
the optical density of the isopropanol-extracts of 3 insert was determined by duplicate per insert = 6 OD values.
PREDICTION MODEL / DECISION CRITERIA:
- The mean optical density (OD) value obtained with the test item was used to calculate the percentage of viability relative to the negative control, which is set at 100 %.
- A category of UN GHS (Category 2 or Category 1) is predicted if the mean percent tissue viability after exposure and post treatment incubation is less than or equal (≤ ) to 50 %.

The irritating potential of the test item is assessed by determination of its cytotoxic effect on an in vitro reconstructed human epidermis. The test principle is based on the MTT assay reflecting the cell viability after exposure to the topically applied test item.
All tests were performed in triplets for each time point. The test item was applied at a 100% concentration, i.e. 30 µl per insert for 20 min. Cell viability was measured by the amount of MTT reduction (calculated on the basis of optical density of the negative control).

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied: 30 μl
- the test item and the solvent ethyl acetate were tested in parallel

NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 30 μl
- Concentration (if solution): 0.9% NaCl

POSITIVE CONTROL
- Amount(s) applied (volume or weight): 30 µl
- Concentration (if solution): 0.3% Sodium Dodecyl Sulfate (SDS)

Duration of treatment / exposure:

20 min

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

3

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

result for test material

Value:

ca. 111

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

DEMONSTRATION OF TECHNICAL PROFICIENCY:
- Reliability of the test was previously confirmed by interlaboratory validation

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: yes
- Acceptance criteria met for positive control: yes
- Acceptance criteria met for variability between replicate measurements: yes

Any other information on results incl. tables

Compound	Cell viability [%]	Evaluation
Armstrongsaure-di-Natriumsalz	110.55	Non-irritant
Positive control	1.02	Irritant
Negative control	100.00	Non-irritant

Applicant's summary and conclusion

Executive summary:

A study was performed for the assessment of the skin irritancy of the test item Armstrongsaure-di-Natriumsalz with reconstructed human epidermis (RhE). The experiment

was carried out in vitro using the commercially available test method epiCS®. The study was conducted in accordance with OECD TG 439 and EU Test Method B.46.

The test item was applied undiluted topically to the RhE tissue construct in triplicates and incubated for 20 minutes, followed by a 42 hours post-treatment incubation period.

Cell viability was measured in a photometer by the amount of MTT (methylthiazole tetrazolium) reduction. The optical density value obtained for the test item was used to

calculate the percentage of viability relative to the negative control, which is set at 100%. The results of the concurrent negative control (NC, 0.9% NaCl) and positive control

(PC, 5 % SDS) demonstrated the viability (NC) and sensitivity (PC) of the test model. The following value of cell viability was recorded for the test item: 111 % (rounded).

In conclusion the results of the assay used show no skin irritant properties of the test item Armstrongsaure-di-Natriumsalz and thus, the test item requires no classification according to UN GHS (Category 2 or Category 1).