Sodium methanesulphonate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 June 2016 - 18 July 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

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:

Sodium methanesulphonate

EC Number:

219-203-2

EC Name:

Sodium methanesulphonate

Cas Number:

2386-57-4

Molecular formula:

CH4O3S.Na

IUPAC Name:

sodium methanesulfonate

Test material form:

liquid

In vitro test system

Test system:

human skin model

Remarks:

reconstructed human epidermis

Source species:

human

Cell type:

other: human epidermal keratinocytes

Cell source:

foreskin from multiple donors

Vehicle:

water

Details on test system:

The EpiskinTM model consists of an airlifted, living, multilayered epidermal tissue construction (surface 0.38 cm2), reconstructed from normal human epidermal keratinocytes for 13 days and produced in polycarbonate inserts in a serum-free and chemically defined medium. The model features a normal ultra structure and is functionally equivalent to human in vivo epidermis supplied by Episkin, Lyon, France.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 µL of the test item.
NEGATIVE CONTROL
- Amount(s) applied (volume or weight): 10 µL
POSITIVE CONTROL
- Amount(s) applied (volume or weight): 10 µL
- Concentration (if solution): SDS at 5% (w/v).

Duration of treatment / exposure:

Exposure period of 15 minutes, followed by rinsing.

Duration of post-treatment incubation (if applicable):

42-hour recovery period.

Number of replicates:

Triplicate tissues for each tested substance (test item, negative control, positive control).

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

15 min exposure + 42h expression

Value:

112

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Other effects / acceptance of results:

- OTHER EFFECTS:
- Visible damage on test system: no
- Direct-MTT reduction: no
- Colour interference with MTT: no

ACCEPTANCE OF RESULTS:
- Acceptance criteria met for negative control: mean cOD of the three negative controls should be = 0.6 and the Standard Deviation (SD) value of the % viability should be = 18%,
- Acceptance criteria met for positive control: relative mean viability of the positive control should be = 40% of the relative mean viability of the negative control and the SD value of the % viability should be = 18%.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

SPS 10LS, is considered to be non-irritant to skin.According to the results of this study, the classification of the test item should be:- no category (UN GHS and Regulation (EC) No. 1272/2008).

Executive summary:

The skin irritation potential of SPS 10LS was evaluated using the Episkin^TMreconstructed human epidermis model. The study design was based upon international guidelines (OECD Guideline No. 439 and Commission Regulation (EC) No. 761/2009, B.46). The studywas conducted in compliance with CiToxLAB France standard operating procedures and the principles of Good Laboratory Practice. Preliminary tests were performed to detect the ability of the test item to directly reduce MTT as well as its colouring potential. Following the preliminary tests, the skin irritation potential of the test item was tested in the main test. The test item and both the negative and positive controls were applied topically on triplicate tissues and incubated at room temperature for 15 minutes. At the end of the treatment period, each tissue was rinsed with D-PBS and incubated for 42 hours at +, 5% CO₂in a humidified incubator. The cell viability was then assessed by means of the colourimetric MTT reduction assay. Relative viability values were calculated for each tissue and expressed as a percentage of the mean viability of the negative control tissues which was set at 100% (reference viability). In addition, the concentration of the inflammatory mediator IL-1awas evaluated in the culture medium retained following the 42-hour recovery period. This quantification, based on an ELISA assay, was performed since the mean relative viability of the test item-treated tissues was > 50% following the MTT reduction assay.

In the preliminary tests, the test item was found not to have direct MTT reducing properties or colouring potential.

All acceptance criteria for the negative and positive controls were fulfilled. The study was therefore considered to be valid.

Following a 15-minute exposure and 42 hours of recovery period, the relative mean viability of the tissues treated with the test item was 112% with a Standard Deviation of 2% as assessed by the MTT assay. As the mean relative viability > 50% after the MTT reduction, the IL-1a concentrations in culture media samples retained from the three negative controls and the three test item-treated tissues were analyzed by ELISA. The IL-1a concentration value of one tissue was found below the limit of quantification (< 5.00 pg/mL). Consequently, the mean IL-1a concentration from the three test item-treated tissues was not calculated. The IL-1aconcentration values of the two other test item-treated tissues were found < 60 pg/mL (i.e. 6.23 and 6.65 pg/mL). Therefore, the results met the criteria for an in vitro classification as non-irritant to skin.

Under the experimental conditions of this study, SPS 10LS is considered to be non-irritant to skin.