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Ecotoxicological information

Toxicity to other aquatic organisms

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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:
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:
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

Reference
Name:
Unnamed
Type:
Constituent
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