Titanium carbide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-08-22 to 2012-08-27

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Standard GLP study performed according to the OECD Guideline 439 (2010).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

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:

Titanium carbide

EC Number:

235-120-4

EC Name:

Titanium carbide

Cas Number:

12070-08-5

Molecular formula:

CTi

IUPAC Name:

titanium carbide

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Titanium carbide
- Substance type: pure active substance
- Physical state: solid
- Batch No.: 82496
- Storage condition of test material: room temperature

Test animals

Species:

human

Test system

Type of coverage:

other: non-relevant, in vitro study with the model EPISKIN-SM

Preparation of test site:

other: non-relevant, in vitro study with the model EPISKIN-SM

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 10 mg (26.3 mg/cm2)
The test material was applied after application of distilled water (5 µl) to the reconstructed human epidermis (Rhe), so as to achive the maximum possible contact.

Duration of treatment / exposure:

15 ± 0.5 min and 42 h post-incubation

Details on study design:

Pre-test: the non-specific MTT-reducing capacity of Titanium carbide was assessed prior to the intitiation of the main study.
Main test: the tissues of the EPISKIN-SM kit were incubated, and therafter treated with each dose group in triplicate. Phosphate buffered saline was used as negative control and 5% sodium dodecyl sulfate in distilled water as positive control. Exposure lasted 15 min and after washing with PBS a 42 hpost-exposure incubation followed. After incubation 2 ml of MTT were transferred in each well. Incubation of 3 h followed. The OD was measured at 550 nm.

Barrier function and morphology, were provided by the Rhe model supplier to assure the proper functioning of the tissues.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

other: other: relative mean tissue viability

Remarks on result:

other:

Remarks:

Remarks: The results are presented in the table below. (migrated information)

In vivo

Irritant / corrosive response data:

See below 'any other information on results incl. tables'.

Any other information on results incl. tables

Table 1: Experimental results of the EPISKIN-SM test after application of Titanium carbide powder.

Name	Negative Control			Positive Control			Test Item
Tissue	1	2	3	1	2	3	1	2	3
Mean OD550of 3 replicate tissues (blank-corrected	0.742			0.184			0.740
SD OD550	0.052			0.080			0.077
Relative tissue viabilities (%)	100.2	104.6	95.2	37.6	21.6	15.1	105.8	105.6	87.9
Mean relative tissue viability (%)	100			25			100
SD tissue viability (%)	4.7			11.6			10.3
CV (% viability)	4.7			46.8			10.3

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Titanium carbide is no irritant in the human skin model EPISKIN-SM.

Executive summary:

In this in vitro dermal irritation study with the three-dimensional human skin model EPISKIN-SM, the irritation potential of Titanium carbide was examined. The test substance was applied topically on the tissue for 15 min, and thereafter the exposed tissue culture was incubated for 42 h. A positive and a negative control were used. The determination of cytotoxic effects was performed with the MTT assay. Irritation potential of the test susbstance was determined based on the cytotoxicity observed (mean tissue viability). The results revealed a mean relative tissue viability higher than 50%, and hence, the test substance is not a skin irritant under the conditions of this test.