Hydroxylammonium chloride

Endpoint summary

Description of key information

Skin sensitisation (guinea pig): sensitising

RA from source substance bis(hydroxyammonium) sulfate (CAS 10039-54-0)

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

refer to analogue justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Details on study design:

B. CHALLENGE EXPOSURE
- Exposure period: 24 h
- Site: naive skin site

Key result

Reading:

1st reading

Group:

test chemical

Dose level:

intradermal induction 5%, challenge 10%

No. with + reactions:

15

Total no. in group:

15

Group:

negative control

Remarks on result:

other: not specified

Group:

positive control

Remarks on result:

other: not specified

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

CLP: Skin Sens. 1, H317 (corresponding to the harmonized classification according to Annex VI of CLP Regulation)

100% of the treated guinea pigs showed a positive reaction. Based on a self-made ranking and classification system (Gad,1988), hydroxylamine sulfate has to be classified in class III (moderate sensitizer).

Based on the test results, the test substance is considered to be skin sensitising category 1. The available data are not sufficient for a decision on the appropriate subcategory according to the criteria of the CLP Regulation.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Sensitisation

Justification for read-across

There are no data available regarding skin sensitisation for Hydroxylammonium chloride (CAS 5470-11-1). Therefore read-across from an appropriate substance is conducted in accordance with Regulation (EC) No 1907/2006, Annex XI, 1.5. in order to fulfil the standard data requirements defined in Regulation (EC) No 1907/2006, Annex VII, 7.3. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across. A detailed justification for the analogue read-across approach is provided in the technical dossier (see IUCLID Section 13).

As no data on skin sensitisation is available for Hydroxylammonium chloride (CAS 5470-11-1), information available for the analogue substance Bis(hydroxyammonium) sulfate (CAS 10039-54-0) are taken into account to fulfil the standard data requirements defined in Regulation (EC) No 1907/2006, Annex VII, 7.3.

 

CAS 110039-54-0

A skin sensitisation study was performed with the test substance according to OECD guideline 406 (Gad et al., 1986). 15 Hartley guinea pigs were treated for 48 h with 5 and 25% test substance for intra- and epidermal induction, respectively. Six animals served as negative control. Epidermal challenge was performed with 10% of the test substance for 24 h. Skin examination revealed positive skin reactions in all 15 animals of the test group. No positive control substance was tested and no information on negative control results is available. Based on the available data, the test substance has to be considered to be a skin sensitiser according to Regulation (EC) No 1272/2008. A conclusive decision on the appropriate subcategory in accordance to the criteria of the CLP Regulation cannot be made based on the available information.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Since the analogue concept is applied to Hydroxylammonium chloride, data will be generated from information on reference source substance(s) to avoid unnecessary animal testing. Additionally, once the analogue read-across concept is applied, substances will be classified and labelled on this basis.

The available data on the relevant read-across substance bis(hydroxyammonium) sulfate (CAS 10039-54-0) for skin sensitisation meet the criteria for classification for Skin Sensitisation, Category 1 (H317). Therefore, applying the RA-A approach, the target substance Hydroxylammonium chloride (CAS 5470-11-1) is also considered to meet the criteria for classification for Skin Sensitisation, Category 1 (H317) according to Regulation (EC) No 1272/2008 (CLP).

The classification is in consistency with the harmonized classification, which is available for the target and the source substance according to Regulation (EC) 1272/2008, Annex VI (both with the Index No. 612-123-00-2), the target substance Hydroxylammonium chloride meets the criteria for classification as Skin Sens Cat. 1, H317.