Manganese dinitrate

Toxicity to other aquatic organisms

Administrative data

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Remarks:

Meets generally accepted scientific standards. The read-across from MnSO4 to Mn(NO3)2 is justified on the following basis: both substances are very soluble in water hence bioavailable and both will release Mn2+ ions. Therefore, from an ecotoxicity standpoint, the nitrate or sulphate anions are not considered to have any influence on the effective toxicity of Mn2+ or any toxicity in their own right, so the anions can be disregarded. Therefore any effect will be related to the Mn2+ cation, and the data from MnSO4 ecotoxicity tests is regarded as a suitable surrogate for read-across

Justification for type of information:

See the read-across report attached in Section 13.

Cross-reference

Reason / purpose for cross-reference:

other: Read-across target

Reference

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Justification for type of information:

See the read-across report attached in Section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

10 d

Dose descriptor:

EC50

Effect conc.:

20.8 mg/L

Conc. based on:

other: Mn

Basis for effect:

mortality

Data source

Reference

Reference Type:

publication

Title:

Toxicity of manganese and zinc to Boreal toad tadpoles (Bufo boreas)

Author:

Davis H, Brinkman S and McIntyre M

Year:

1998

Bibliographic source:

Federal aid project #F-243R-5, , Colorado Division of Wildlife, Fort Collins, Colorado

Materials and methods

Test guideline

Qualifier:

no guideline available

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

manganese sulphate

IUPAC Name:

manganese sulphate

Details on test material:

- Name of test material (as cited in study report): Manganese sulphate monohydrate

Sampling and analysis

Analytical monitoring:

not specified

Test organisms

Test organisms (species):

Bufo boreas

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

10 d

Results and discussion

Effect concentrations

Duration:

10 d

Dose descriptor:

EC50

Effect conc.:

20.8 mg/L

Conc. based on:

other: Mn

Basis for effect:

mortality

Any other information on results incl. tables

Manganese concentrations were stable throughout the 24 hour period between renewals.

Mortality did not occur in manganese exposures of 10 mg Mn/L or less. In the 50 mg/L exposure, 40% mortality occurred by 96 hours leading to complete mortality by 168 hours. Mortality in the 100 mg/L exposure started as soon as 24 hours and resulted in complete mortality by 96 hours. The 96 and 168 hour LC50 were 42.3 and 20.8 mg Mn/L respectively

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The LC50 was 42.3 mg Mn/L. The read-across from MnSO4 to Mn(NO3)2 is justified on the following basis: both substances are very soluble in water hence bioavailable and both will release Mn2+ ions. Therefore, from an ecotoxicity standpoint, the nitrate or sulphate anions are not considered to have any influence on the effective toxicity of Mn2+ or any toxicity in their own right, so the anions can be disregarded. Therefore any effect will be related to the Mn2+ cation, and the data from MnSO4 ecotoxicity tests is regarded as a suitable surrogate for read-across