Blue MGi 1037-Na (notification presscake)

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000-06-23 to 2000-10-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 95 % C.L. (2.7 - 9.6 mg/L)

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95 % C.L. (9 - 27 mg/L)

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

33 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 95 % C.L. (25 - 44 mg/L)

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Validity criteria fulfilled:

yes

Conclusions:

The 72-h EC50 value was determined to be > 100 mg/L.

Executive summary:

The aim of this study was to determine the inhibitory effect of Blue MGi 1037 on the growth of the freshwater green algal species Scenedesmus subspicatus in a 72 -h static test according to OECD 201. The method was modified to quantify the algicidal effect of the test item, but also the growth inhibition effect caused by reduced light intensities in the colored test solution. Nominal test concentrations were 1.0, 3.2, 10, 32 and 100 mg/L. The same growth inhibition of Scenedesmus subspicatus was observed when the algae grew in test water without test item, but under reduced light intensities by the filter effect of the colored test media as in the second parallel experimental part, where the algae grew in the test media with dissolved test item.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

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

Adequacy of study:

key study

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Description of key information

The 72-h EC50 value for the read across source substance Blue MGi 1037 was determined to be > 100 mg/L.

Key value for chemical safety assessment

EC50 for freshwater algae:

100 mg/L

Additional information

The aim of this study was to determine the inhibitory effect of Blue MGi 1037 on the growth of the freshwater green algal speciesScenedesmus subspicatusin a 72 -h static test according to OECD 201. The method was modified to quantify the algicidal effect of the test item, but also the growth inhibition effect caused by reduced light intensities in the colored test solution. Nominal test concentrations were 1.0, 3.2, 10, 32 and 100 mg/L. The same growth inhibition of Scenedesmus subspicatus was observed when the algae grew in test water without test item, but under reduced light intensities by the filter effect of the colored test media as in the second parallel experimental part, where the algae grew in the test media with dissolved test item.