1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 October 2015 - 26 October 2015

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)

Version / remarks:

Variation between the three identically treated negative control tissues exceeded the ≤ 18% standard deviation limit as given in the study protocol. The standard deviation for the negative control group in this study was 20%. However as there was a high confidence in the results, ie there were no borderline results in the negative control, positive control or test item treated groups a repeat of the study was considered unnecessary.

Deviations:

yes

Remarks:

This deviation was considered not to affect the purpose or integrity of the study.

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Variation between the three identically treated negative control tissues exceeded the ≤ 18% standard deviation limit as given in the study protocol. The standard deviation for the negative control group in this study was 20%. However as there was a high confidence in the results, ie there were no borderline results in the negative control, positive control or test item treated groups a repeat of the study was considered unnecessary.

Deviations:

yes

Remarks:

This deviation was considered not to affect the purpose or integrity of the study.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

bis(2,4,4-trimethylpentan-2-yl)trisulfane

EC Number:

941-787-9

Cas Number:

98222-50-5

Molecular formula:

C16 H34 S3

IUPAC Name:

bis(2,4,4-trimethylpentan-2-yl)trisulfane

Test material form:

liquid

Details on test material:

Name: DAILUBE IS-30
Chemical Name: 1, 3-bis (2, 4, 4-trimethylpentan-2yl) trisulfane
Use: Lubricant Additive
Molecular Formula: CH3-C(CH3)2-CH2-C(CH3)2-SSS-C(CH3)2-CH2-C(CH3)2-CH3
Molecular Weight: 322 g/mol
Appearance Pale yellow
Physical State: Liquid
Batch Number: L002
Purity: 95.4% by weight
Storage: Room temperature, in the dark
Expiry Date: 2016/8/15

Specific details on test material used for the study:

Batch: L002
Purity: 95.4%
Physical state / Appearance: Pale yellow liquid
Expiry date: 15 August 2016
Storage Conditions: Room temperature in the dark

In vitro test system

Test system:

human skin model

Source species:

human

Cell type:

non-transformed keratinocytes

Cell source:

other: The main basal, supra basal, spinous and granular layers and a functional stratum corneum.

Source strain:

not specified

Justification for test system used:

Reconstructed human epidermis model showed evidence of being a reliable and relevant stand-alone test for predicting rabbit skin irritation when the endpoint is measured by MTT reduction and for being used as a replacement for the Draize Skin Irritation Test for the purpose of distinguishing between Irritating and Non-Irritating test items.

Vehicle:

unchanged (no vehicle)

Details on test system:

TEMPERATURE USED FOR TEST SYSTEM
- Temperature used during treatment / exposure: 37 °C
- Temperature of post-treatment incubation (if applicable): 37 °C
DYE BINDING METHOD
- Dye used in the dye-binding assay:MTT
- Spectrophotometer: microplate reader
- Wavelength: 562 nm
- Filter:without
- Filter bandwidth: na
NUMBER OF INDEPENDENT TESTING RUNS / EXPERIMENTS TO DERIVE FINAL PREDICTION:
PREDICTION MODEL / DECISION CRITERIA
- The test substance is considered to be irritant to skin if relative mean tissue viability is ≤50%
- The test substance is considered to be non-irritant to skin if relative mean tissue viability is >50%

Control samples:

yes, concurrent negative control

yes, concurrent positive control

yes, concurrent MTT non-specific colour control

Amount/concentration applied:

TEST MATERIAL
- Amount(s) applied: 10 µL
- Concentration (if solution): 26.3 µL/cm2

NEGATIVE CONTROL
- Amount(s) applied: 10 µL of DPBS

POSITIVE CONTROL
- Amount(s): 10 µL of SDS 5% w/v: positive control

Duration of treatment / exposure:

15 minutes

Duration of post-treatment incubation (if applicable):

42 hours

Number of replicates:

Triplicate tissues

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Run / experiment:

Main

Value:

82.6

Vehicle controls validity:

not applicable

Negative controls validity:

not valid

Remarks:

There were no borderline results in the negative control, positive control or test item treated groups a repeat of the study was considered unnecessary.

Positive controls validity:

valid

Remarks on result:

no indication of irritation

Other effects / acceptance of results:

Mean OD562 Values and Percentage Viabilities for the Negative Control Item, Positive Control Item and Test Item (Table 1).

Any other information on results incl. tables

Table 1: Mean OD562 Values and Percentage Viabilities for the Negative Control Item, Positive Control Item and Test Item

Item	OD562of tissues	Mean OD562of triplicate tissues	±SD of OD562	Relative individual tissue viability (%)	Relative mean viability (%)	± SD of Relative mean viability (%)
Negative Control Item	0.871	0.702	0.146	124.1	100*	20.8
	0.619			88.2
	0.617			87.9
Positive Control Item	0.042	0.084	0.041	6.0	12.0	5.9
	0.124			17.7
	0.085			12.1
Test Item	0.642	0.580	0.056	91.5	82.6	8.0
	0.564			80.3
	0.534			76.1

OD=Optical Density

SD=       Standard deviation

*=        The mean viability of the negative control tissues is set at 100%

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

UN GHS Not classified for Irritation (category 3 can not be determined).

Conclusions:

The test item was classified as non-irritant.
The following classification criteria apply:
EU DSD & CLP Not classified for Irritation.
UN GHS Not classified for Irritation (category 3 can not be determined).