Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well documented study according to internationally accepted guidelines and GLP compliant.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2013
Report date:
2013

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

Constituent 1
Chemical structure
Reference substance name:
α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol
EC Number:
246-042-5
EC Name:
α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol
Cas Number:
24155-42-8
Molecular formula:
C11H10Cl2N2O
IUPAC Name:
1-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethanol
Test material form:
solid: crystalline
Details on test material:
Test item: IMIDAZOLE ETHANOL (CAS No. 24155-42-8)
Batch No.: L36066N
Physical state: Light-yellow powder
Active ingredient content (titrimetry): 92.1%
Impurities (HPLC): 9.18%
Storage: 15-30°C

Test system

Details on study design:
Human skin model:
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 (Tinois et al., 1994). 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.
Justification for selection of the test system: The EPISKIN model has been validated for irritation testing in an international trial.

Results and discussion

In vitro

Results
Irritation / corrosion parameter:
other:
Remarks on result:
other: EPISKIN
Other effects / acceptance of results:
Disks of EPISKIN (three units / chemical) were treated with test item and incubated for 15 minutes at room temperature. Exposure of test material was terminated by rinsing with PBS 1x solution. Epidermis units were then incubated at 37 °C for 42 hours in an incubator with 5% CO2. The viability of each disk was assessed by incubating the tissues for 3 hours with MTT solution at 37°C in 5% CO2 protected from light. The formazan precipitated was then extracted using acidified isopropanol and quantified spectrophotometrically.
SDS (5% aq.) and PBS treated epidermis were used as positive and negative controls respectively. For each treated tissue viability was expressed as a percentage relative to negative control.
The test item is considered to be irritant to skin, if the mean relative viability after 15 minutes exposure and 42 hours post incubation is less or equal (≤) to 50% of the negative control.

Any other information on results incl. tables

Substance

Optical Density (OD)

Viability (%)

Negative Control:

1 x PBS

mean

0,631

100

standard deviation (SD)

3,11

Positive Control:

SDS (5%aq.)

mean

0,228

36

standard deviation (SD)

1,33

Test Item:

IMIDAZOLE ETHANOL

mean

0,370

59

standard deviation (SD)

6,51

 

Applicant's summary and conclusion

Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
In this in vitro skin irritation test in the EPISKIN model with test item “IMIDAZOLE ETHANOL” (CAS No. 24155-42-8) the results indicated that the test item is Non Irritant (NI) [UN GHS: No Category].