4-chloro-2-nitroaniline

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation

Remarks:

other: QSAR

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: OECD QSAR Toolbox for Grouping Chemicals into Categories

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Qualifier:

according to guideline

Guideline:

other: based on: Guidance on information requirements and chemical safety assessment, Chapter R.6: QSARs and grouping of chemicals (ECHA, May 2008)

Qualifier:

according to guideline

Guideline:

other: based on: Guidance Document on the Validation of (Quantitative) Structure-Activity Relationship Models (OECD, September 2007)

Qualifier:

according to guideline

Guideline:

other: based on: GUIDANCE DOCUMENT FOR USING THE OECD (Q)SAR APPLICATION TOOLBOX TO DEVELOP CHEMICAL CATEGORIES ACCORDING TO THE OECD GUIDANCE ON GROUPING OF CHEMICALS (OECD Feb. 2009)

Principles of method if other than guideline:

QSAR Toolbox prediction of skin sensitisation potential based on read-across

GLP compliance:

no

Type of study:

other: QSAR

results of the QSAR prediction described in the sield "executive summary"

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: expert judgment

Conclusions:

The predicted value using the QSAR toolbox is "negative". The substance is therefore considered to be not sensitising.

Executive summary:

Method

Most skin sensitizing organic chemicals must initially react covalently with skin proteins before being recognized by the immune system as skin sensitizers. But for the target chemical 4-chloro-2-nitroaniline, no protein-binding profiler is identified, which means that there is no specific mechanism or mode of action relevant for the endpoint of sensitization. Therefore, structure similarity is used for conducting a primary grouping.

Prediction of the skin sensitizing potential of 4 -chloro-2 -nitroaniline was assessed by collecting a set of test data for chemicals considered to be in the same category. The category is defined by the structure similarity common to all the chemicals in the category

The prediction was based on dataset comprised from the following endpoints: "Skin sensitization"

Estimation method: Taking highest mode value from the 5 nearest neighbours, based on 11 data points from 5 neighbour chemicals.

Domain logical expression:Result: In Domain

("a" and ("b" and "c") )

Domain logical expression index: "a"

Similarity boundary: Target: c1(N)c(N(=O)=O)cc(Cl)cc1; Threshold=80%, Dice(Atom pairs).

Domain logical expression index: "b"

Parametric boundary: The target chemical should have a value of log Kow which is >= 2.45.

Domain logical expression index: "c"

Parametric boundary: The target chemical should have a value of log Kow which is <= 3.1.

Prediction approach:

Read-across among category members:

1-chloro-4-nitrobenzene, CAS 100 -00 -5 (Negative, 2x)

1-chloro-2-nitrobenzene, CAS 88 -77 -3 (Negative, 1x; Positive, 1x)

2-chloro-6-nitrotoluene, CAS 83-42-1 (Negative, 1x)

1,2-dichloro-4-nitrobenzene, CAS 99 -54 -7 (Negative, 5x)

1,4-dichloro-2-nitrobenzene, CAS 89 -61 -2 (Negative, 1x)

Experimental values for the target substance (if any) were not used in prediction calculations.

Result

The target substance FALLS within applicability domain.

Prediction confidence: 90.9%

10 of 11 neighbours' data points have experimental value equal to prediction "Negative"

The predicted value using the QSAR toolbox is "negative".

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

QSAR-Analysis using the OECD QSAR Toolbox revealed a negative prediction for skin sensitizing properties with a confidence level of 90.9%. Experimental result (positive) is published in the literature but no methodological data are given for an assessment. Therefore 4-chloro-2 -nitroaniline was considered to be not a skin sensitizer.

Migrated from Short description of key information:
OECD QSAR toolbox: negative
Experimental result: positive, but no methodological data given for an assessment
Conclusion for 4-chloro-2-nitroaniline: negative

Justification for classification or non-classification

Available data from QSAR-Analysis support the conclusion that classification is not warranted.