1-ethyl-3-methyl-3H-imidazolium dicyanidoamide(1-)

Eye irritation

Administrative data

Endpoint:

eye 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:

guideline study

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 492 (Reconstructed Human Cornea-like Epithelium (RhCE) Test Method for Identifying Chemicals Not Requiring Classification and Labelling for Eye Irritation or Serious Eye Damage)

Version / remarks:

July, 2015

Principles of method if other than guideline:

according to:
- MatTek Corporation, Ashland, MA 01721, USA: EpiOcularTM human cell construct: Procedure details, Version 3.1a of February 10, 2010.
- Harbell J.W. et al. (2009): COLIPA Program on Optimization of Existing In Vitro Eye Irritation Assays for Entry into Formal Validation: Technology Transfer and Intra/Inter Laboratory Evaluation of EpiOcular Assay for Chemicals. Poster # 378, Society of Toxicology, March 2009.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3-ethyl-1-methyl-1H-Imidazolium salt with N-cyanocyanamide (1:1)

EC Number:

609-330-5

Cas Number:

370865-89-7

Molecular formula:

C6 H11 N2 .C2 N3

IUPAC Name:

3-ethyl-1-methyl-1H-Imidazolium salt with N-cyanocyanamide (1:1)

Specific details on test material used for the study:

- Name of the test substance (as cited in study report): EMIM Dicyanamid
- Purity: 97.4 g/100 g
- pH value: ca. 5 (undiluted test substance)

Test animals / tissue source

Species:

other: reconstructed human cornea model

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

Amount / concentration applied:

50 uL

Duration of treatment / exposure:

30 min

Duration of post- treatment incubation (in vitro):

2-hour post-incubation period

Number of animals or in vitro replicates:

Two tissues (test group)

Details on study design:

To remove the test substance, the tissues were washed with sterile PBS. For this purpose the tissues were immersed and swiveled three times in each of three beakers filled with PBS. Washed tissues were immediately immersed into 12-well plates, pre-filled with 5 mL/well prewarmed medium (post-soak immersion) in order to remove residual test substance. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation using a colorimetric test. The reduction of mitochondrial dehydrogenase activity, measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the test substance treated epidermal tissues is compared to that of negative control tissues. The quotient of the values indicates the relative tissue viability. After 12 minutes of post-soak immersion, each tissue was dried on absorbent paper and transferred to fresh 6-well plates filled with 1 mL/well pre-warmed medium. Subsequently, the tissues were incubated at standard culture conditions for 2 hours (liquids) (postincubation period). The irritation potential of the test materials is predicted from the mean relative tissue viabilities compared to the negative control tissues concurrently treated with sterile water. A chemical is considered as "irritant", if the mean relative tissue viability with a test material is less than or equal to 50%. According to the new OECD guideline 492 (July 28th, 2015), the percentage tissue viability cut-off value distinguishing classified from non-classified test chemicals is 60%.

Results and discussion

In vitro

Results

Irritation parameter:

other: mean viability in %

Value:

69

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Remarks:

H2O

Positive controls validity:

valid

Remarks:

Methyl acetate

Remarks on result:

no indication of irritation

In vivo

Irritant / corrosive response data:

The test substance is not able to reduce MTT directly.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met