Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
29 Feb - 02 Mar 2007
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
no
Analytical monitoring:
no
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Water Accomodated Fraction (WAF): A concentration of 100 mg/L of the test substance was moderately stirred in algal medium for 24 h at
room temperature. After this incubation time, the undissolved materials were removed by sterile filtration (0.45 µm) to obtain a sterile test substance solution for the algal growth test. The resulting water accommodated fraction was used in the test.
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Strain: 86.81 SAG
- Source: obtained from the collection of Algal Cultures, Institute of Freshwater Ecology, University of Göttingen, Göttingen, Germany
Age of inoculum (at test initiation): Exponentially growing liquid preculture were used to inoculate sterile test flasks.
- Method of cultivation: 250 mL flask containing 100 mL of sterile OECD medium inoculated with cell material from axenic slope culture, continuous
illumination from warm white fluorescent tubes (8500 - 9000 lux), temperature: 22 ± 0.2 °C thermocontrolled room, periodically conducted
reference test with potassium dichromate.
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Hardness:
not stated
Test temperature:
22 ± 0.2 °C
pH:
8.0 ± 0.2
Nominal and measured concentrations:
Nominal: 100 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Material: glass; Size: 250 mL; Fill volume: 100 mL
- Initial cells density: 10000 - 20000/mL
- No. of vessels per concentration: 3
- No. of vessels per control: 5

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: OECD medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature was determined in a control flask at the start and at the end of the test. The pH was determined in 1 control flask after sterilization before the test and in all test vessels at the end of the test. Observations of mis-shapen cells and cell-debris were made after 24, 48 and 72 h test duration.

OTHER TEST CONDITIONS
- Photoperiod: continuous
- Light intensity and quality: warm white fluorescent tubes (8500-9000 lux)

EFFECT PARAMETERS MEASURED: Algal growth was recorded after 24, 48 and 72 h test duration.
- Determination of cell concentrations: using a spectrophotometer (680 nm wavelength). Aliquots of 5 mL were removed from each test
substance served as controls. The starting cell density was determined using a counting chamber.
Reference substance (positive control):
no
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: EL50 (24-72h)
Duration:
72 h
Dose descriptor:
EL0
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: EL0 (24-72h)
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: EL50 (24-72h)
Duration:
72 h
Dose descriptor:
EL0
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: EL0 (24-72h)
Details on results:
- Exponential growth in the control: yes
- Observation of abnormalities: no

At the WAF loading rate of 100 mg/L no inhibition with respect to algal growth rate and algal cell growth (area under growth curve) compared to the untreated controls were observed. The no-observed-effect concentration for growth rates (ErL0) and biomass production (EbL0) with respect to the loading rate was ≥ 100 mg/L. The EL50 -value was conducted as EL50 (24 -72 h). But the EL50 can also be stated as EL50 (72 h) > 100 mg/L for the algal growth rate and algal cell growth.

Table 1: Cell concentration (A680) in individual test cultures after 24, 48 and 72 h of exposure to the test material. ((b) = Mean absorbance (A680))

Nominal concentration [mg/L]

Code

Cell concentration (A680)

0 h (b)

24 h

48 h

72 h

Control

A

B

C

D

E

0.008

0.008

0.008

0.008

0.008

0.033

0.038

0.038

0.036

0.040

0.228

0.222

0.208

0.212

0.233

0.685

0.733

0.676

0.624

0.694

100

A

B

C

0.008

0.008

0.008

0.040

0.038

0.044

0.224

0.207

0.207

0.700

0.631

0.675

 

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
22 - 25 Jul 1999
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions (no purity)
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Version / remarks:
(1984)
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
yes (incl. QA statement)
Remarks:
The Department of Health of the Government of the United Kingdom (date of inspection 23 Mar 1998)
Analytical monitoring:
yes
Details on sampling:
- Concentrations: Water samples were taken from the control (replicates R1-R2 pooled) and the 100 mg/L loading rate WSF test group (replicates R1-R3 and R4-R6 pooled) at 0 and 72 h.
- Sample storage conditions before analysis: Duplicate samples were taken at 0 h and stored frozen (approx. -20°C) for further analysis if necessary.
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: An amount of test material (2000 mg) was added to the vortex created in 20 L of culture medium to give a 100 mg/L loading rate. The mixture was stirred for 23 h with a vortex depth of approx. 25%. After stirring the mixture was allowed to stand for 1 h prior to the removal of the WSF by filtration through 0.45 µm filters. An aliquot (2000 mL) of the WSF was inoculated with algal suspension (10 mL) to give the final test concentration of 100 mg/L loading rate WSF.
- Controls: reverse osmosis purified deionised water (Elga Optima 15+) without test item
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Common name: green algae
- Strain: CCAP 276/20
- Source: Culture Centre for Algae and Protozoa (CCAP), Institute of Freshwater Ecology, Ferry House, Ambleside, Cumbria
- Method of cultivation: The culture was maintained in the laboratory at a temperature of 21 ± 1 °C under continuous light (approx. 7000 lux) and constant aeration. The culture medium was prepared according to the OECD guideline (AAP medium).
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Test temperature:
24 ± 1 °C
pH:
7.3-7.6 (0 h), 8.0-8.8 (control, 72 h), 8.8 - 9.7 (100 mg/L, 72 h)
Nominal and measured concentrations:
Nominal concentrations: 100 mg/L
Measured concentrations: 100 mg/L (12.6 and 17.9 mg/L, 0 h; 5.89 and 2.07 mg/L, 72 h)
Details on test conditions:
TEST SYSTEM
- Test vessel: 250 mL glass conical flasks each containing 100 mL of solution
- Type: covered with aluminium foil
- Aeration: constantly shaken at 100 rpm
- Initial cells density: 1.26 - 1.66x10E+04 cells/mL
- Control end cells density: 3.64x10E+05 cells/mL
- No. of vessels per concentration: 6
- No. of vessels per control: 3

GROWTH MEDIUM
- Standard medium used: yes, according to OECD guideline

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reverse osmosis purified deionised water (Elga Optima 15+)

OTHER TEST CONDITIONS
- Adjustment of pH: adjusted to 7.5 ± 0.1 with 0.1 N NaOH or HCl
- Photoperiod: continuous light
- Light intensity and quality: approx. 7000 lux

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: samples were taken at 0, 24, 48 and 72 h and the cell densities were determined by using a Coulter Multisizer II Particle Counter

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 100 mg/L (WAF)
- Results used to determine the conditions for the definitive study: No effect on growth at 100 mg/L loading rate WAF.
Reference substance (positive control):
no
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOELR
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
biomass
Details on results:
- Exponential growth in the control: yes
- Any stimulation of growth found in any treatment: an increase of growth was observed in the highest test concentration after 72 h.
- Effect concentrations exceeding solubility of substance in test medium: The nominal effect concentration of 100 mg/L exceeded the water solubility of the test substance.
Reported statistics and error estimates:
Statistical analysis of the area under the growth curve data was carried out for the control and 100 mg/L loading rate WSF test group using a Students t-test.

No effects on the growth rate was observed in the range of water solubility of the test substance with an EL50 of > 100 mg/L based on the growth rate. The measured concentrations of the test item in the test vessels were much lower than the nominal loading rate (Table 3).

Table 1: Cell densities in the definitive study

 

Cell densities [cells/mL]

Nominal loading rate [mg/L]

0 h

24 h

48 h

72 h

Control R1

1.34x104

2.29 x104

7.69 x104

3.79 x105

R2

1.34 x104

2.16 x104

8.80 x104

3.53 x105

R3

1.10 x104

2.22 x104

9.83 x104

3.60 x105

Mean

1.26 x104

2.22 x104

8.78 x104

3.64 x105

100 R1

1.67 x104

2.38 x104

6.14 x104

5.19 x105

R2

1.80 x104

2.42 x104

8.11 x104

5.23 x105

R3

1.37 x104

2.44 x104

6.29 x104

3.50 x105

R4

1.54 x104

2.49 x104

7.26 x104

4.01 x105

R5

1.93 x104

2.41 x104

7.64 x104

6.62 x105

R6

1.61 x104

2.41 x104

6.60 x104

6.65 x105

Mean

1.66 x104

2.42 x104

7.01 x104

5.20 x105

Table 2: Inhibition of growth rate and biomass

Nominal loading rate [mg/L]

Area under curve at 72 h

% inhibition

Growth rate (0-72 h)

% inhibition

control

6.25 x106

-

0.047

 

100

7.51 x106

[20]

0.048

[2]

[increase in growth as compared to the controls]

Table 3: Chemical analysis of test loading rates

Samples

Nominal loading rate [mg/L]

Concentration found [mg/L]

Expressed as a % of the nominal loading rate

0 h

control

< LOQ

-

100 R1-R3

12.6

13

100 R4-R6

17.9

18

72 h

control

< LOQ

-

100 R1-R3

5.89

6

100 R4-R6

2.07

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
Study period:
29 Feb - 02 Mar 2007
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
Please refer to IUCLID Section 13 for the detailed justification of the Analogue Approach.
Reason / purpose for cross-reference:
read-across source
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
no
Analytical monitoring:
no
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Water Accomodated Fraction (WAF): A concentration of 100 mg/L of the test substance was moderately stirred in algal medium for 24 h at
room temperature. After this incubation time, the undissolved materials were removed by sterile filtration (0.45 µm) to obtain a sterile test substance solution for the algal growth test. The resulting water accommodated fraction was used in the test.
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Strain: 86.81 SAG
- Source: obtained from the collection of Algal Cultures, Institute of Freshwater Ecology, University of Göttingen, Göttingen, Germany
Age of inoculum (at test initiation): Exponentially growing liquid preculture were used to inoculate sterile test flasks.
- Method of cultivation: 250 mL flask containing 100 mL of sterile OECD medium inoculated with cell material from axenic slope culture, continuous
illumination from warm white fluorescent tubes (8500 - 9000 lux), temperature: 22 ± 0.2 °C thermocontrolled room, periodically conducted
reference test with potassium dichromate.
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Hardness:
not stated
Test temperature:
22 ± 0.2 °C
pH:
8.0 ± 0.2
Nominal and measured concentrations:
Nominal: 100 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Material: glass; Size: 250 mL; Fill volume: 100 mL
- Initial cells density: 10000 - 20000/mL
- No. of vessels per concentration: 3
- No. of vessels per control: 5

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: OECD medium
- Culture medium different from test medium: no
- Intervals of water quality measurement: Temperature was determined in a control flask at the start and at the end of the test. The pH was determined in 1 control flask after sterilization before the test and in all test vessels at the end of the test. Observations of mis-shapen cells and cell-debris were made after 24, 48 and 72 h test duration.

OTHER TEST CONDITIONS
- Photoperiod: continuous
- Light intensity and quality: warm white fluorescent tubes (8500-9000 lux)

EFFECT PARAMETERS MEASURED: Algal growth was recorded after 24, 48 and 72 h test duration.
- Determination of cell concentrations: using a spectrophotometer (680 nm wavelength). Aliquots of 5 mL were removed from each test
substance served as controls. The starting cell density was determined using a counting chamber.
Reference substance (positive control):
no
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: EL50 (24-72h)
Duration:
72 h
Dose descriptor:
EL0
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: EL0 (24-72h)
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: EL50 (24-72h)
Duration:
72 h
Dose descriptor:
EL0
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: EL0 (24-72h)
Details on results:
- Exponential growth in the control: yes
- Observation of abnormalities: no

At the WAF loading rate of 100 mg/L no inhibition with respect to algal growth rate and algal cell growth (area under growth curve) compared to the untreated controls were observed. The no-observed-effect concentration for growth rates (ErL0) and biomass production (EbL0) with respect to the loading rate was ≥ 100 mg/L. The EL50 -value was conducted as EL50 (24 -72 h). But the EL50 can also be stated as EL50 (72 h) > 100 mg/L for the algal growth rate and algal cell growth.

Table 1: Cell concentration (A680) in individual test cultures after 24, 48 and 72 h of exposure to the test material. ((b) = Mean absorbance (A680))

Nominal concentration [mg/L]

Code

Cell concentration (A680)

0 h (b)

24 h

48 h

72 h

Control

A

B

C

D

E

0.008

0.008

0.008

0.008

0.008

0.033

0.038

0.038

0.036

0.040

0.228

0.222

0.208

0.212

0.233

0.685

0.733

0.676

0.624

0.694

100

A

B

C

0.008

0.008

0.008

0.040

0.038

0.044

0.224

0.207

0.207

0.700

0.631

0.675

 

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
22 - 25 Jul 1999
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions (no purity)
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
Please refer to IUCLID Section 13 for the detailed justification of the Analogue Approach.
Reason / purpose for cross-reference:
read-across source
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Version / remarks:
(1984)
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
yes (incl. QA statement)
Remarks:
The Department of Health of the Government of the United Kingdom (date of inspection 23 Mar 1998)
Analytical monitoring:
yes
Details on sampling:
- Concentrations: Water samples were taken from the control (replicates R1-R2 pooled) and the 100 mg/L loading rate WSF test group (replicates R1-R3 and R4-R6 pooled) at 0 and 72 h.
- Sample storage conditions before analysis: Duplicate samples were taken at 0 h and stored frozen (approx. -20°C) for further analysis if necessary.
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: An amount of test material (2000 mg) was added to the vortex created in 20 L of culture medium to give a 100 mg/L loading rate. The mixture was stirred for 23 h with a vortex depth of approx. 25%. After stirring the mixture was allowed to stand for 1 h prior to the removal of the WSF by filtration through 0.45 µm filters. An aliquot (2000 mL) of the WSF was inoculated with algal suspension (10 mL) to give the final test concentration of 100 mg/L loading rate WSF.
- Controls: reverse osmosis purified deionised water (Elga Optima 15+) without test item
Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
TEST ORGANISM
- Common name: green algae
- Strain: CCAP 276/20
- Source: Culture Centre for Algae and Protozoa (CCAP), Institute of Freshwater Ecology, Ferry House, Ambleside, Cumbria
- Method of cultivation: The culture was maintained in the laboratory at a temperature of 21 ± 1 °C under continuous light (approx. 7000 lux) and constant aeration. The culture medium was prepared according to the OECD guideline (AAP medium).
Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Test temperature:
24 ± 1 °C
pH:
7.3-7.6 (0 h), 8.0-8.8 (control, 72 h), 8.8 - 9.7 (100 mg/L, 72 h)
Nominal and measured concentrations:
Nominal concentrations: 100 mg/L
Measured concentrations: 100 mg/L (12.6 and 17.9 mg/L, 0 h; 5.89 and 2.07 mg/L, 72 h)
Details on test conditions:
TEST SYSTEM
- Test vessel: 250 mL glass conical flasks each containing 100 mL of solution
- Type: covered with aluminium foil
- Aeration: constantly shaken at 100 rpm
- Initial cells density: 1.26 - 1.66x10E+04 cells/mL
- Control end cells density: 3.64x10E+05 cells/mL
- No. of vessels per concentration: 6
- No. of vessels per control: 3

GROWTH MEDIUM
- Standard medium used: yes, according to OECD guideline

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reverse osmosis purified deionised water (Elga Optima 15+)

OTHER TEST CONDITIONS
- Adjustment of pH: adjusted to 7.5 ± 0.1 with 0.1 N NaOH or HCl
- Photoperiod: continuous light
- Light intensity and quality: approx. 7000 lux

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: samples were taken at 0, 24, 48 and 72 h and the cell densities were determined by using a Coulter Multisizer II Particle Counter

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 100 mg/L (WAF)
- Results used to determine the conditions for the definitive study: No effect on growth at 100 mg/L loading rate WAF.
Reference substance (positive control):
no
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOELR
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Remarks:
(WAF)
Basis for effect:
biomass
Details on results:
- Exponential growth in the control: yes
- Any stimulation of growth found in any treatment: an increase of growth was observed in the highest test concentration after 72 h.
- Effect concentrations exceeding solubility of substance in test medium: The nominal effect concentration of 100 mg/L exceeded the water solubility of the test substance.
Reported statistics and error estimates:
Statistical analysis of the area under the growth curve data was carried out for the control and 100 mg/L loading rate WSF test group using a Students t-test.

No effects on the growth rate was observed in the range of water solubility of the test substance with an EL50 of > 100 mg/L based on the growth rate. The measured concentrations of the test item in the test vessels were much lower than the nominal loading rate (Table 3).

Table 1: Cell densities in the definitive study

 

Cell densities [cells/mL]

Nominal loading rate [mg/L]

0 h

24 h

48 h

72 h

Control R1

1.34x104

2.29 x104

7.69 x104

3.79 x105

R2

1.34 x104

2.16 x104

8.80 x104

3.53 x105

R3

1.10 x104

2.22 x104

9.83 x104

3.60 x105

Mean

1.26 x104

2.22 x104

8.78 x104

3.64 x105

100 R1

1.67 x104

2.38 x104

6.14 x104

5.19 x105

R2

1.80 x104

2.42 x104

8.11 x104

5.23 x105

R3

1.37 x104

2.44 x104

6.29 x104

3.50 x105

R4

1.54 x104

2.49 x104

7.26 x104

4.01 x105

R5

1.93 x104

2.41 x104

7.64 x104

6.62 x105

R6

1.61 x104

2.41 x104

6.60 x104

6.65 x105

Mean

1.66 x104

2.42 x104

7.01 x104

5.20 x105

Table 2: Inhibition of growth rate and biomass

Nominal loading rate [mg/L]

Area under curve at 72 h

% inhibition

Growth rate (0-72 h)

% inhibition

control

6.25 x106

-

0.047

 

100

7.51 x106

[20]

0.048

[2]

[increase in growth as compared to the controls]

Table 3: Chemical analysis of test loading rates

Samples

Nominal loading rate [mg/L]

Concentration found [mg/L]

Expressed as a % of the nominal loading rate

0 h

control

< LOQ

-

100 R1-R3

12.6

13

100 R4-R6

17.9

18

72 h

control

< LOQ

-

100 R1-R3

5.89

6

100 R4-R6

2.07

2

Description of key information

No effects up to the limit of water solubility; read-across.

Key value for chemical safety assessment

Additional information

Since no studies investigating the short-term toxicity of Tetraesters of pentaerythritol with heptanoic acid and 3,5,5-trimethylhexanoic acid (List number 805-289-4) to aquatic algae are available, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 a read-across to the structurally related source substances 3,5,5-trimethylhexanoic acid mixed tetraesters with PE and valeric acid (CAS 131459-39-7) and Fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) was conducted. The target substance is characterized as a tetraester of pentaerythritol and heptanoic acid and 3,5,5-trimethylhexanoic acid. The source substances are structurally very similar to the target substance. 3,5,5-trimethylhexanoic acid mixed tetraesters with PE and valeric acid (CAS 131459-39-7) is mainly a tetraester of 3,5,5-methylhexanoic acid and pentaerythritol. The source substance Fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) is a triester of trimethylolpropane and C8-C10 fatty acids (even numbered). This read-across is justified in detail in the overall summary (IUCLID Section 6.1) and within the analogue justification in IUCLID Section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substance was used for the assessment.

The study with the read-across substance 3,5,5-trimethylhexanoic acid mixed tetraesters with PE and valeric acid (CAS 131459-39-7) was performed according to OECD 201 (1984, GLP) and investigated the toxicity to freshwater algae (Mead, 1999). The green algae Scenedesmus subspicatus was exposed for 72 h to a limit Water Soluble Fraction (WSF) of nominal 100 mg/L. GC/FID analysis resulted in a measured concentrations of 12.6 and 17.9 mg/L at test start and 5.89 and 2.07 mg/L at test end. No effects on growth and biomass of algae were observed resulting in an EL50 of > 100 mg/L (nominal). The NOELR was derived to be ≥ 100 mg/L (nominal). 

The second study with the source substance Fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) was performed according to OECD 201 (non-GLP) is available investigating the toxicity to aquatic algae (Häner, 2007). Desmodesmus subspicatus was exposed to a nominal loading rate of 100 mg/L for 72 h (Water Accommodated Fraction). No effects were observed on growth and biomass after 72 h of incubation resulting in an EL50 (72 h) > 100 mg/L (nominal) and an EL0 (72 h) ≥ 1000 mg/L (nominal).

Based on the available results from structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by a similar ecotoxicological profile and comparable structure, it can be concluded that Tetraesters of pentaerythritol with heptanoic acid and 3,5,5-trimethylhexanoic acid will not exhibit effects on aquatic algae up to the limit of water solubility.