1-amidino-2-thiourea

Skin irritation / corrosion

Administrative data

Endpoint:

skin corrosion: in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

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:

1-amidino-2-thiourea

EC Number:

218-308-0

EC Name:

1-amidino-2-thiourea

Cas Number:

2114-02-5

Molecular formula:

C2H6N4S

IUPAC Name:

1-(Diaminomethylidene)thiourea

Test material form:

solid: crystalline

Specific details on test material used for the study:

Supplier: Changzou Foreign Trade Corp.Batch No.: 0041A25 (20141211)Physical state: solid substance, crystalline powderColour: whiteStorage: in a cool, dry place, protected from light

In vitro test system

Test system:

human skin model

Source species:

human

Details on test system:

EpiSkinTM Small Model (EpiSkinTMSM), manufactured by EPISKIN SNC Lyon, France, is a three-dimensional human epidermis model. Adult human-derived epidermal keratinocytes are seeded on a dermal substitute consisting of a collagen type I matrix coated with type IV collagen. A highly differentiated and stratified epidermis model is obtained after 13-day culture period comprising the main basal, supra basal, spinous and granular layers and a functional stratum corneum. Its use for skin irritation testing involves topical application of test materials to the surface of the epidermis, and the subsequent assessment of their effects on cell viability.

Control samples:

yes, concurrent negative control

yes, concurrent positive control

Amount/concentration applied:

10 mg of the test item was applied evenly onto the skin.

Duration of treatment / exposure:

The plates with the treated epidermis units were incubated for the exposure time of 15 minutes (± 0.5 min) at room temperature.

Duration of post-treatment incubation (if applicable):

After rinsing the units were placed into the plate wells with fresh pre-warmed “maintenance medium” (2 mL/well) below them and then incubated for 42 hours (± 1h) at 37°C in an incubator with 5 % CO2.

Number of replicates:

Three replicates were used for the test item and controls respectively.

Results and discussion

In vitro

Results

Irritation / corrosion parameter:

% tissue viability

Value:

65

Vehicle controls validity:

not examined

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The results obtained from this in vitro skin irritation test, using the EPISKIN model, indicated that the test item reveals no skin irritation potential under the utilised testing conditions. The test item AMIDINOTHIOUREA (CAS No. 2114-02-5) is considered to be non-irritant to skin and is therefore not classified (UN GHS No Category).