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Administrative data

Description of key information

No data available for p-TSH.

For OBSH no testing data is available, however 61 of 246 notifiers use a classification as Skin Sens 1 for OBSH. It is not known whether this is related to human observations, but if some hydrolysis occurs on the humid skin this would result in formation of hydrazine which based on human evidence is classified as a skin sensitiser. Using the OECD QSAR Toolbox V3.1 resulted in a positive prediction for skin sensitisation.

No reliable QSAR-predictions onp-TSH could be made using VEGA, Danish DTU QSAR or the OECD Toobox. Thus, a precautious approach would be to consider p-TSH as a skin sensitiser based on read-across to hydrazine and OBSH.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin sensitisation, other
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
No data available for target substance (T) - Toluene-4-sulphonohydrazide (p-TSH).

Read-across from one closely structural and physicochemical related substance: 4,4'-Oxybis (benzenesulfonyl hydrazide) (OBSH).

For OBSH no testing data is available, however 61 of 246 notifiers use a classification as Skin Sens 1 for OBSH. It is not known whether this is related to human observations, but if some hydrolysis occurs on the humid skin this would result in formation of hydrazine which based on human evidence is classified as a skin sensitiser. Using the OECD QSAR Toolbox V3.1 resulted in a positive prediction for skin sensitisation.

No reliable QSAR-predictions on p-TSH could be made using the QSAR VEGA programme, the Danish QSAR database or the OECD QSAR Toobox. Thus, a precautious approach would be to consider p-TSH (T) as a skin sensitiser based on read-across to OBSH and hydrazine.

For further read-across justification see document attached in section 13.
Reason / purpose:
read-across source
Related information:
Composition 1
Test material information:
Composition 1
Remarks on result:
positive indication of skin sensitisation based on QSAR/QSPR prediction
Interpretation of results:
Category 1 (skin sensitising) based on GHS criteria
Executive summary:

No data is available for Toluene-4-sulphonohydrazide (T).

Therefore, read-across from the closely structural and physicochemical related substance 4,4'-Oxybis (benzenesulfonyl hydrazide) (OBSH) has has been used.

For OBSH no testing data is available, however 61 of 246 notifiers use a classification as Skin Sens 1 for OBSH. It is not known whether this is related to human observations, but if some hydrolysis occurs on the humid skin this would result in formation of hydrazine which based on human evidence, is classified as a skin sensitiser. Using the OECD QSAR Toolbox V3.1 resulted in a positive prediction for skin sensitisation.

Therefore, according to CLP criteria OBSH is classified as Skin Sens. 1; H317.

No reliable QSAR-predictions on p-TSH could be made using the QSAR VEGA programme, the Danish QSAR database or the OECD QSAR Toobox. Thus, a precautious approach would be to consider p-TSH as a skin sensitiser based on read-across to OBSH and hydrazine. Thus, according to CLP criteria p-TSH should be classified as Skin Sens. 1; H317.

For further read-across justification see document attached in section 13.

Endpoint:
skin sensitisation, other
Remarks:
in vivo
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Justification for type of information:
The prediction was based on dataset comprised from the following descriptors: "A B C" Estimation method: Takes highest mode value from the 5 nearest neighbours Domain  logical expression:Result: In Domain ("a" and ("b" and "c" )  ) Domain logical expression index: "a" Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Carbenium Ion Formation AND SN1 >> Carbenium Ion Formation >> Hydrazine by DNA binding by OECD Domain logical expression index: "b" Parametric boundary:The target chemical should have a value of log Kow which is >= -1.58 Domain logical expression index: "c" Parametric boundary:The target chemical should have a value of log Kow which is <= 0.797
Reference:
Composition 0
Guideline:
other: REACH Guidance on QSARs R.6 - Read across using the OECD QSAR Toolbox V3.1
Test material information:
Composition 1
Specific details on test material used for the study:
c1(S(=O)(=O)NN)ccc(Oc2ccc(S(=O)(=O)NN)cc2)cc1
Remarks on result:
other: QSAR prediction result
Remarks on result:
other: QSAR prediction result
Remarks:
QSAR prediction made using the OECD QSAR Toolbox
Remarks on result:
other: QSAR prediction result

The prediction was based on dataset comprised from the following descriptors: "A B C"
Estimation method: Takes highest mode value from the 5 nearest neighbours
Domain  logical expression:Result: In Domain

("a" and ("b" and "c" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as SN1 AND SN1 >> Carbenium Ion Formation AND SN1 >> Carbenium Ion Formation >> Hydrazine by DNA binding by OECD

Domain logical expression index: "b"

Parametric boundary:The target chemical should have a value of log Kow which is >= -1.58

Domain logical expression index: "c"

Parametric boundary:The target chemical should have a value of log Kow which is <= 0.797

The Toolbox made read-across from phenylhydrazine CAS 100 -63 -0 and from mercapto-acetic acid hydrazide CAS 760 -30 -5 both of which were considered as skin senstisers and predicted OBSH to be positive for skin sensitisation.

This can supported by the fact that OBSH by hydrolysis generate hydrazine which is CLH-classified as Skin sens. 1.


Interpretation of results:
other: Positive
Remarks:
Criteria used for interpretation of results: EU
Conclusions:
Test substance is a skin sensitizer based on OECD-toolbox prediction and read-across
Executive summary:

OECD QSAR Toolbox V3.1 has been used and read across results showed that the substance is a skin sensitizer.

The Toolbox made read-across from phenylhydrazine CAS 100 -63 -0 and from mercapto-acetic acid hydrazide CAS 760 -30 -5 both of which were considered as skinsenstisers and predicted OBSH to be positive for skin sensitisation.

This can be supported by the fact that OBSH by hydrolysis generate hydrazine which is CLH-classified as Skin sens. 1.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (sensitising)

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

No data available for p-TSH.

For OBSH no testing data is available, however 61 of 246 notifiers use a classification as Skin Sens 1 for OBSH. It is not known whether this is related to human observations, but if some hydrolysis occurs on the humid skin this would result in formation of hydrazine which based on human evidence is classified as a skin sensitiser. Using the OECD QSAR Toolbox V3.1 resulted in a positive prediction for skin sensitisation.

No reliable QSAR-predictions onp-TSH could be made using VEGA, Danish DTU QSAR or the OECD Toobox. Thus, a precautious approach would be to consider p-TSH as a skin sensitiser based on read-across to hydrazine and OBSH.

For further read-across justification see document attached in section 13.