Manganese bis(dihydrogen phosphate)

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study has been performed according to a standard methodology and under laboratory conditions. There is no indication of GLP compliance and such this study is considered to be justified for use as a key study in accordance with Regulation (EC) No. 1907/2006 (REACH) Annex XI, Section 1.1. Further this study is considered to be adequate and reliable for the purpose of assessing sensitisation potential in accordance with Regulation (EC) No 1272/2008 (EU CLP). Read-across in accordance with Annex XI, Section 1.5 of Regulation (EC) No. 1907/2006 (REACH) is justified on the following basis: Manganese phosphates such as manganese hydrogen phosphate and manganese bis(dihydrogen phosphate) are soluble manganese-containing inorganic compounds. The toxicology of these materials is considered to be related to the presence of the Mn2+ ion (as phosphate itself is not considered to be toxic). As such it is scientifically justified to read-across to other soluble materials containing Mn2+. In this instance the manganese chloride is considered to be appropriate as the chloride ion itself shows no propensity for sensitisation.

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

yes

Remarks:

No justification for choice of vehicle (not a standard vehicle for this study)

Principles of method if other than guideline:

The protocol used followed the standard methodology as described in Kimber I, Basketter DA (1992) The murine local lymph node assay;collaborative studies and new directions: A commentary. Food ChemToxicol. 30:165-169.

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Olac, Bicester, UK
- Age at study initiation: 7-12 weeks

Vehicle:

other: petrolatum

Concentration:

5, 10, 25%

No. of animals per dose:

4 (3 dose groups: vehicle and test)

Details on study design:

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Murine Local Lymph Node Assay
- Criteria used to consider a positive response: A substance was regarded as a skin sensitizer if, at any concentration, the proliferation in treated lymph nodes was threefold or greater than that in the concurrent vehicle treated controls

Parameter:

SI

Remarks on result:

other: Test Concentration Stimulation Index 5.0% 1.1 10.0% 0.6 25.0% 1.0

Authors state that the negative result obtained in the LLNA study corresponds to human observations in which manganese is not considered to be a sensitiser.

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Manganese chloride and hence manganese itself is not considered to be a sensitiser under the conditions of this study.
Read-across in accordance with Annex XI, Section 1.5 of Regulation (EC) No. 1907/2006 (REACH) is justified on the following basis:
Manganese phosphates such as manganese hydrogen phosphate and manganese bis(dihydrogen phosphate) are soluble manganese-containing inorganic compounds. The toxicology of these materials is considered to be related to the presence of the Mn2+ ion (as phosphate itself is not considered to be toxic). As such it is scientifically justified to read-across to other soluble materials containing Mn2+. In this instance the manganese chloride is considered to be appropriate as the chloride ion itself shows no propensity for sensitisation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Read-across in accordance with Annex XI, Section 1.5 of Regulation (EC) No. 1907/2006 (REACH) is justified on the following basis:

Manganese phosphates such as manganese hydrogen phosphate and manganese bis(dihydrogen phosphate) are soluble manganese-containing inorganic compounds. The toxicology of these materials is considered to be related to the presence of the Mn2+ ion (as phosphate itself is not considered to be toxic). As such it is scientifically justified to read-across to other soluble materials containing Mn2+. In this instance the manganese chloride is considered to be appropriate as the chloride ion itself shows no propensity for sensitisation.

Justification for selection of skin sensitisation endpoint:
One key study available. Study is sufficient to assess the sensitisation potential of soluble inorganic Mn2+ compounds.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Manganese bis(dihydrogen phosphate) is not considered to be a sensitiser on the basis of read-across for the Mn2+ ion.