Reaction products of 4-amino-3-hydroxy-7-nitronaphthalene-1-sulfonic acid and 2′,4′-dihydroxyacetophenone chelated with iron, sodium salts

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:

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

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Source study has reliability 2, due to low purity of test sample. Details on the read across are available in section 13.

Qualifier:

according to guideline

Guideline:

other: guideline 79/831/EEC, Annex V, part C

GLP compliance:

no

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: a stock solution (200 mg/l) was prepared by dissolving the substance in deionised water

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: CHODAT SAG 86.81
- Source (laboratory, culture collection): obtained from collection of algal cultures in Göttingen, Germany

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

23 ± 2° C

pH:

7.40 - 9.38

Nominal and measured concentrations:

Nominal test substance concentrations:
0 (control), 0.16, 0.31, 0.63, 1.25, 2.5, 5, 10, 20 and 100 mg/l

Analytically determined concentrations:
10.2 mg/l (10 mg/l nominal)
1.23 mg/l (1.25 mg/l nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask (250 ml)
- Fill volume: 100 ml
- Initial cells density: 10000 cells/ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionised

OTHER TEST CONDITIONS
- Photoperiod: continous illumination
- Light intensity and quality: 120 μEinstein/m*m*s, Color of light is universal white, L 25 (Osram)

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: electronic particle counter
- Chlorophyll measurement: light flashes, wavelength 435 nm

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

10.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

71.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.19 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

18.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate and biomass

Conclusions:

EC50 (72h) = 71.8 mg/l based on growth rate.

Executive summary:

Method:

Toxicity to algae was assessed following EEC 79/831 Annex V part C. Nominal test substance concentrations were 0 (control), 0.16, 0.31, 0.63, 1.25, 2.5, 5, 10, 20 and 100 mg/l. For each concentration, 3 replicates were tested. Effects on growth rate and biomass were assessed 0, 24, 48 and 72 h after start.

Results:

Effects on growth rate after 72 h:

EC10 = 10.3 mg/l

EC50 = 71.8 mg/l

EC90 > 100 mg/l

Effects on biomass after 72 h:

EC10 = 0.19 mg/l

EC50 = 18.4 mg/l

EC90 > 100 mg/l

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

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

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Source study has reliability 2, due to low purity of test sample. Details on the read across are available in section 13.

Qualifier:

according to guideline

Guideline:

other: guideline 79/831/EEC, Annex V, part C

GLP compliance:

no

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: a stock solution (400 mg/l) was prepared by dissolving the substance in deionised water.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: CHODAT SAG 86 .81
- Source (laboratory, culture collection): obtained from collection of algal cultures in Göttingen, Germany

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

23 ± 2°C

pH:

7.91 - 9.72

Nominal and measured concentrations:

Nominal test substance concentrations:
control, 0.16, 0.31, 0.63, 1.25, 2.5, 5, 10, 20 and 100 mg/l

Analytically determined concentrations:
0.17 mg/l (0.078 mg/l nominal)
19.4 mg/l (20 mg/l nominal)
397 mg/l (400 mg/l nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask (250 ml)
- Fill volume: 100 ml
- Initial cells density: 10000 cells/ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionised

OTHER TEST CONDITIONS
- Photoperiod: continous illumination
- Light intensity and quality: 120 μEinstein/m*m*s, Color of light is universal white, L 25 (Osram)

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: electronic particle counter
- Chlorophyll measurement: light flashes, wavelength 435 nm

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

21.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

80.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

2.73 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

32.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: growth rate and biomass

Conclusions:

EC50 (72h) = 80.8 mg/l based on growth rate.

Executive summary:

Method:

Toxicity to algae was assessed following EEC 79/831 Annex V part C. Nominal test substance concentrations were 0 (control), 0.16, 0.31, 0.63, 1.25, 2.5, 5, 10, 20 and 100 mg/l. For each concentration, 3 replicates were tested. Effects on growth rate and biomass were assessed 0, 24, 48 and 72 h after start.

Results:

Effects on growth rate after 72 h:

EC10 = 21.8 mg/l

EC50 = 80.8 mg/l

EC90 > 100 mg/l

Effects on biomass after 72 h:

EC10 = 2.73 mg/l

EC50 = 32.9 mg/l

EC90 > 100 mg/l

Description of key information

EC50 (72h) algae = 71.8 mg/l (nominal)

Key value for chemical safety assessment

EC50 for freshwater algae:

71.8 mg/L

Additional information

No data on target substance was available, thus a read across approach was followed, using data on Similar Substance 01. Details are reported in section 13.

Toxicity to aquatic algae was assessed in 2 studies on Similar Substance 01, under static exposure conditions and exposure duration of 72 h. Both studies were well-documented and reliable, thus the study reporting the lowest EC50 value was selected as key study by following a precautionary approach.

In both studies, toxicity to algae was assessed according to guideline 79/831/EEC Annex V, part C; nominal concentrations on Similar Substance 01 were 0, 0.16, 0.31, 0.63, 1.25, 2.5, 5, 10, 20, 100 mg/l, divided in 3 replicates per concentration; effects on growth rate and biomass were recorded 0, 24, 48 and 72 h after start of exposure.

After 72 hour, EC50 values of 71.8 and 80.8 mg/l based on growth rate were found.