Registration Dossier

Administrative data

Endpoint:
skin sensitisation, other
Remarks:
QSAR
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Justification for type of information:
1. SOFTWARE
QSAR dyes R&C version 5.2

2. MODEL (incl. version number)
QSAR skin sensitization (v. 2.0)

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
EC No.: 228-800-7
CI: Basic Yellow 21

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
- Defined endpoint: Skin senitisation
- Unambiguous algorithm: The developed model is based on locàl similàrity based on à set of molecular descriptors
- Defined domain of applicability: A model report is provided informing about the limitations of eàch prediction in its structural domain and response space.
- Appropriate measures of goodness-of-fit and robustness and predictivity: Procedures to understand if the model is able to reliàbly predict skin sensitization for external test samples were properly applied.
- Mechanistic interpretation: see attachment

5. APPLICABILITY DOMAIN
see attachment Skin Sensitzation QSAR Model

6. ADEQUACY OF THE RESULT
see attached prediction report

Data source

Reference
Reference Type:
other: QSAR Report
Title:
Unnamed
Year:
2018

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: Practical guide How to use and report (Q)SARs
Principles of method if other than guideline:
SKIN SENSITIZATION QSAR MODEL
REPORT N. 08 – 29/04/2016
Project: Study of potential toxicity of dyes by read-across approach and QSAR modelling
Developed by:
Milano Chemometrics and QSAR Research Group, Dept. Earth and Environmental Sciences, University Milano-Bicocca, Italy

GLP compliance:
no
Justification for non-LLNA method:
QSAR prediction

Test material

Constituent 1
Chemical structure
Reference substance name:
2-[2-(2,3-dihydro-2-methyl-1H-indol-1-yl)vinyl]-1,3,3-trimethyl-3H-indolium chloride
EC Number:
228-800-7
EC Name:
2-[2-(2,3-dihydro-2-methyl-1H-indol-1-yl)vinyl]-1,3,3-trimethyl-3H-indolium chloride
Cas Number:
6359-50-8
Molecular formula:
C22H25N2.Cl
IUPAC Name:
(1Z)-2-methyl-1-{2-[(2Z)-1,3,3-trimethyl-2,3-dihydro-1H-indol-2-ylidene]ethylidene}-2,3-dihydro-1H-1lambda5-indol-1-ylium chloride
Test material form:
solid: particulate/powder

Results and discussion

In vivo (LLNA)

Results
Key result
Remarks on result:
no indication of skin sensitisation based on QSAR/QSPR prediction
Cellular proliferation data / Observations:
QSAR skin sensitization (v. 2.0)
Applicability domain: in applicability domain
QSAR prediction: not sensitizing
Reliability score: 0.67
Number of similar structures: 2
Average similarity to nearest structures: 0.60
Occurrence frequency Negative: 1.00
Skin sensitization alerts: none

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
QSAR prediction: not sensitizing
Executive summary:

QSAR skin sensitization (v. 2.0)

Applicability domain: in applicability domain

QSAR prediction: not sensitizing

Reliability score: 0.67

Number of similar structures: 2

Average similarity to nearest structures: 0.60

Occurrence frequency

Negative: 1.00

Skin sensitization alerts: none