Manganese dichloride

Endpoint summary

Description of key information

Non-sensitiser based on weight of evidence.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Consistent with OECD guideline, no claim of GLP compliance.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

yes

Remarks:

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

GLP compliance:

no

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

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

No further data available

Vehicle:

other: petrolatum

Concentration:

5%, 10% and 25% MnCl2 in petrolatum

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: 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

The mice (n=4) received 25 µl of test chemical solution, or vehicle alone, on the dorsum of each ear. The application was repeated for three consecutive days. Five days following the initial application mice were injected with 250μl of phosphate-buffered saline (PBS) containing 20 μCi of H-methyl thymidine into all test and control mice via the tail vein. Five hours later the mice were exterminated and the draining lymph nodes (auricular and axillary) were excised and pooled per animal. Incorporation of 3H-methyl thymidine in the lymph node cells is measured by β-scintillation counting as disintegrations per minute(DPM). Stimulation index(SI) is obtained by dividing the pooled radioactive incorporation for each treatment group by the incorporation of the pooled vehicle control group; this yields a mean SI.

Positive control substance(s):

not specified

Key result

Parameter:

SI

Value:

1.1

Test group / Remarks:

5.0 %

Key result

Parameter:

SI

Value:

0.6

Test group / Remarks:

10.0 %

Key result

Parameter:

SI

Value:

1

Test group / Remarks:

25.0 %

Interpretation of results:

not sensitising

Conclusions:

Manganese dichloride is not a sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Across 4 studies utilising MnCl2 or other manganese inorganic salts in animals or humans, there was no evidence of skin sensitisation, (either with MgCl2 specifically in LLNAs by Basketter et al., and Ikarashi et al., or human patch tests with MnCl2 or other Mn salts by Santucci et al., and Menezes et al).

Justification for selection of skin sensitisation endpoint:
Study with the test material, consistent with the LLNA OECD guideline, although no claim of GLP compliance.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

No classification based upon two negative LLNA studies on manganese chloride (IUCLID section 7.4.1, Basketter et al and Ikarashi et al ).