Dimanganese trioxide

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

For details on the read across justification refer to the read across statement in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 other: % v/v saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of the test item to the freshwater invertebrate Daphnia magna has been investigated and gave a 48-Hour EC50 of greater than 100% v/v saturated solution. Correspondingly the No Observed Effect Concentration was 100% v/v saturated solution.

Based on the mean measured test concentration as test item the 48-hour EC50 was estimated to be greater than 0.0735 mg/l. Correspondingly the No Observed Effect Concentration was 0.0735 mg/l.

This study showed that there were no toxic effects at saturation.

Executive summary:

The short term toxicity of the test material to aquatic invertebrates was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 202 and EU Method C.2.

As the test material is considered to be poorly soluble in water the study was conducted with a saturated solution of test material.

Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals) were exposed to an aqueous solution of the test material at a concentration of 100% v/v saturated solution for 48 hours at a temperature of approximately 20°C under static test conditions. The test material solution was prepared by stirring an excess (100 mg/L) of test material in reconstituted water using a magnetic stirrer at approximately 100 rpm for 48 hours. After the stirring period any undissolved test material was removed by filtration through a 0.2 µm filter to give a saturated solution of the test material. Immobilisation and any adverse reactions to exposure were recorded after 24 and 48 hours.

A positive control conducted approximately every six months used potassium dichromate as the reference item. Daphnia magnawere exposed to an aqueous solution of the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L for 48 hours at a temperature of approximately 20°C under static test conditions. Immobilisation and any adverse reactions to exposure were recorded after 24 and 48 hours. No daphnia immobilisation was observed over the 48 hour test period. The 48-hour EC50 was therefore determined to be greater than 100% v/v saturated solution. This study showed that there were no toxic effects at the limit of solubility of the test material in the test medium.

This information is used in a read-across approach in the assessment of the target substance.

Description of key information

Under the conditions of the valid study reported by Goodband & Mullee (2010), the acute toxicity of manganese dioxide to the freshwater invertebrate Daphnia magna has been investigated and gave a 48-hr EC50 of greater than 100% v/v saturated solution. Correspondingly the No Observed Effect Concentration was 100% v/v saturated solution. This study showed that there were no toxic effects at saturation. This information is used in a read-across approach in the assessment of the target substance dimanganese trioxide.

Additional information

The information on manganese dioxide is used in a read-across approach in the assessment of dimanganese trioxide.

For details on the read across justification refer to the read across statement in IUCLID section 13.