Octanoic acid, monoester with glycerol

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:

weight of evidence

Study period:

2. to 5. March 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions: Not all validity criteria can be verified.

Qualifier:

according to guideline

Guideline:

other: Guideline 88/302/EWG (Algal Inhibition Test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock solution of the poorly soluble test substance was prepared by adding 1 g/L of the test substance into destilled water and subsequently stirring for 18h. Afterwards the solution was filtrated and the TOC content was determined. The DOC content of the stock solution is 1.3 mg/L which equals to 2.0 mg/L of the test substance.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: CHODAT 86.81 SAG
- Source (laboratory, culture collection): Institut für Wasser-, Boden- und Lufthygiene Berlin - afterwards own cultivation
- Method of cultivation: Three days before start of the test, a preculture was reared from a stock culture with a cell density of about 20000 cells/mL.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

24 +/- 2°C

pH:

Test start: 8.1 - 8.3
End of test: 9.0 - 9.2

Nominal and measured concentrations:

Nominal concentrations: 0, 0.2, 0.34, 0.6, 1.0, 1.8 mg/L
The nominal concentrations were calculated from the concentration (TOC measured) of the stock solution and related to the test substance. It can not be ruled out that the test substance concentration is caused by the diester component included in the triester.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: Erlenmeyer flasks
- Aeration: yes, sterile aeration
- Initial cells density: 2*10^4 cells/mL
- Control end cells density: 76*10^4 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3


GROWTH MEDIUM
- Standard medium used: yes


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: destilled water
- Intervals of water quality measurement: pH at the beginning and at the end


OTHER TEST CONDITIONS
- Photoperiod: continuously
- Light intensity and quality: 8000 Lux


EFFECT PARAMETERS MEASURED: after 0, 24, 48 and 72 hours
- Determination of cell concentrations: Photometrically: The absorption was measured at 685 nm. The values were converted into cells/mL with the help of a calibration curve.


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Details on results:

- Exponential growth in the control: yes
- Observation of abnormalities: not mentioned
- Effect concentrations exceeding solubility of substance in test medium: no

Reported statistics and error estimates:

The EC values could not be calculated with a probit analysis as no effect was observed.

Under conditions tested no effect up to the limit of the water solubility of the test substance was observed.

Table 1: Mean values of cell numbers in dependency of test duration and test substance concentration. The concentrations are based on the test substance.

Cell numbers (*10^4 cells/mL)
Concentration (mg/L)	Test duration (h)
	0 h*	24 h	48 h	72 h
Control	2	5	24	76
0.20	2	6	23	77
0.34	2	6	24	76
0.60	2	5	22	76
1.0	2	6	25	85
1.8	2	6	23	84

* no mean value

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

14. November to 17. November 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

. Additionally consideration of the "VCI-Konzept-Entwurfes für die (akute) aquatische Prüfung von schwerlöslichen Stoffen vom 31.1. 1994"

Deviations:

yes

Remarks:

only 300 lux light intensity

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: both test runs (a) separated from undissolved test substance and b) directly weighed in)
- Sampling method: Samples were taken at 0, 24, 48, 72 hours

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Due to the low solubility of the test substance two different test solutions were prepared according to the VCI-concept for poorly soluble substances.
a) Test solution with 100 mg/L and subsequently separation of unsolved test substance: 100 mg test substance were added to 1 L test medium and stirred for 24h. Afterwards the unsolved test substance was separated by filtration with a fibre glass filter (pretreated with 1 molar NaOH). For each replicate 100 mL aliquot of the filtrate were used, with algae inoculated and incubated.
b) 100 mg/L directly weighed in solution
The test substance was directly weighed in and shaked for 24h in a Clim-O-Shake.
To each replicate 10 mL of a 10times-concentrate of the mineral medium (according to DIN 38412/9) was added and subsequently filled up to 100 mL with deionised water. Afterwards the algae suspension was added and the incubation started.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Source (laboratory, culture collection): Pflanzenphysiol. Inst. of University Göttingen


ACCLIMATION
- Acclimation period: 3 to 4 days of preincubation in test medium without test substance

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

23°C

pH:

Control: 8.0 (0h); 9.8 - 10.4 (72h)
Test solution a) 8.0 (0h); 10.4 (72h)
Test solution b) 8.0 (0h); 8.6 (72h)
The increase of the pH during the incubation time was not caused by the substance but results from the strong cell growth of the algal cells. A significant influence onto the test result is unlikely.

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
Measured concentrations:
Test solution a) separation of undissolved matter: 0h - < 0.05 mg/L; 24h - < 0.05 mg/L; 48 h - < 0.05 mg/L; 72h < 0.05 mg/L. The recovery was lower than the LOQ which means that the separation was quantitative.
Test solution b) directly weighed in without separation: 0h - 78.9 mg/L; 24h - 18.9 mg/L; 48 h - 6.0 mg/L; 72h - 5.0 mg/L. Due to the inhomogeniety of the test suspension, the recovery was at test begin 80% and decreased to 5% from 0h to 72h.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 300 mL Erlenmeyer flasks, filled with 100 mL
- Initial cells density: 10^4 cells/mL
- Control end cells density: 8.6x10^5 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3


GROWTH MEDIUM
- Standard medium used: yes, according to DIN 38412/9


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionised water
- Culture medium different from test medium: preadaption to test medium for 3-4 days)
- Intervals of water quality measurement: after 72h


OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: not mentioned
- Photoperiod: continuous
- Light intensity and quality: 300 Lux (daylight spectrum)


EFFECT PARAMETERS MEASURED: growth rate after 24, 48 and 72h
- Determination of cell concentrations: Coulter counter


TEST CONCENTRATIONS
- Spacing factor for test concentrations: limit test

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 10 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: test solution a) with separation of undissolved test substance; no effect up to the limit of the water solubility of test substance was observed.

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

< 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: test solution b) without separation of undissolved test substance

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no
- Any observations that might cause a difference between measured and nominal values: yes, in test solution b) where the undissolved matter was not filtered out
- Other observations: After an incubation time of 24h bacteria growth was observed in 2 of 3 replicates and after 48h/72h in all replicates of solution a). For solution b) bacteria growth was observed after 24h/48h/72h as well as a cloudiness.
- Effect concentrations exceeding solubility of substance in test medium: In test solution b) an effect was observed which can be attributed to the undissolved matter (see Remarks on results including tables and figures)

The test with test solution a), a test solution where the undissolved test substance was filtered out, showed no effects on the growth rate of Scenedesmus subspicatus. Therewith, it can be stated that no effect up to the limit of the water solubility of the test substance occurred under conditions tested.

Thus, the massive inhibition of algae growth observed in test solution b) where the undissolved test substance was not filtered out, can be attributed to physical impacts of the undissolved test substance and not to a systemic toxicity of the test substance.

Table 1: Cell concentrations and pH-values

Nominal test substance concentration [mg/L]	Alga cell concentrations [1/mL]			pH values
	Incubation time [h]			Incubation time [h]
	24	48	72	0	72
Control	4.3E+04	2.4E+05	8.6E+05	8.0	9.8-10.4
100 a)	4.0E+04	1.75E+05	1.1E+06	8.0	10.4
100 b)	2.7E+04	6.7E+04	7.3E+04	8.0	8.6

 

 

Table 2: Growth rates and inhibition of growth rates

Concentration [mg/L]	Growth rates after ¿h incubation
	24 [cells/(mL*h)]	48 [cells/(mL*h)]	72 [cells/(mL*h)]
0	0.0611	0.0659	0.0618
100 a)	0.0578	0.0594	0.0650
100 b)	0.0409	0.0395	0.0277
	Inhibition of growth rates after ¿ h incubation
	24 [%]	48 [%]	72 [%]
100 a)	5.5	9.8	-5.1
100 b)	33.1	40.0	55.2

 

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

14. November to 17. November 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

. Additionally consideration of the "VCI-Konzept-Entwurfes für die (akute) aquatische Prüfung von schwerlöslichen Stoffen vom 31.1. 1994"

Deviations:

yes

Remarks:

only 300 lux light intensity

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: both test runs (a) separated from undissolved test substance and b) directly weighed in
- Sampling method: Samples were taken at 0, 24, 48, 72 hours

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Due to the low solubility of the test substance two different test solutions were prepared according to the VCI-concept for poorly soluble substances.
a) Test solution with 100 mg/L and subsequently separation of unsolved test substance: 100 mg test substance were added to 1 L test medium and stirred for 24h. Afterwards the unsolved test substance was separated by filtration with a fibre glass filter (pretreated with 1 molar NaOH). For each replicate 100 mL aliquot of the filtrate were used, with algae inoculated and incubated.
b) 100 mg/L directly weighed in solution
The test substance was directly weighed in and shaked for 24h in a Clim-O-Shake.
To each replicate 10 mL of a 10times-concentrate of the mineral medium (according to DIN 38412/9) was added and subsequently filled up to 100 mL with deionised water. Afterwards the algae suspension was added and the incubation started.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Source (laboratory, culture collection): Pflanzenphysiol. Inst. of University Göttingen


ACCLIMATION
- Acclimation period: 3 to 4 days of preincubation in test medium without test substance

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test temperature:

23°C

pH:

Control: 8.0 (0h); 9.8 - 10.4 (72h)
Test solution a) 7.8 (0h); 10.4 (72h)
Test solution b) 7.8 (0h); 8.3 (72h)
The increase of the pH during the incubation time was not caused by the substance but results from the strong cell growth of the algal cells. A significant influence onto the test result is unlikely.

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
Measured concentrations:
Test solution a) separation of undissolved matter: 0h - 0.14 mg/L; 24h - < 0.05 mg/L; 48 h - 0.05 mg/L; 72h < 0.05 mg/L. The recovery of the test substance at the beginning and after 48 hours was slightly above the detection limit, which means that the separation was not complete.
Test solution b) directly weighed in without separation: 0h - 59.42 mg/L; 24h - 37.72 mg/L; 5.13 mg/L; 6.32 mg/L. Due to the increasing separation of the test suspension during the incubation period, the recovery decreased from approx. 60% to 5% from 0h to 72h.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 300 mL Erlenmeyer flasks, filled with 100 mL
- Initial cells density: 10^4 cells/mL
- Control end cells density: 8.6x10^5 cells/mL
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3


GROWTH MEDIUM
- Standard medium used: yes, according to DIN 38412/9


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionised water
- Culture medium different from test medium: preadaption to test medium for 3-4 days
- Intervals of water quality measurement: after 72h


OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: not mentioned
- Photoperiod: continuous
- Light intensity and quality: 300 Lux (daylight spectrum)


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : growth rate and biomass after 24, 48 and 72h
- Determination of cell concentrations: Coulter counter


TEST CONCENTRATIONS
- Spacing factor for test concentrations: limit test

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: test solution a) with separation of undissolved test substance; no effect up to the limit of the water solubility of test substance was observed.

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 10 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: test solution a) with separation of undissolved test substance; no effect up to the limit of the water solubility of test substance was observed.

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 10 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: test solution a) with separation of undissolved test substance; no effect up to the limit of the water solubility of test substance was observed.

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

< 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: test solution b) without separation of undissolved test substance

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: yes, in test solution b) where the undissolved matter was not filtered out
- Effect concentrations exceeding solubility of substance in test medium: In test solution b) an effect was observed which can be attributed to the undissolved matter (see Remarks on results including tables and figures)

The test with test solution a), a test solution where the undissolved test substance was filtered out (preparation of a Water Accommodated Fraction (WAF)), showed no effects on the growth rate of Scenedesmus subspicatus. Therewith, it can be stated that no effect up to the limit of the water solubility of the test substance occurred under conditions tested.

Thus, the slight effect on algae growth observed in test solution b) where the undissolved test substance was not filtered out, can be attributed to physical impacts of the undissolved test substance and not to a systemic toxicity of the test substance.

Table 1: Cell concentrations and pH-values

Nominal test substance concentration [mg/L]	Alga cell concentrations [1/mL]			pH values
	Incubation time [h]			Incubation time [h]
	24	48	72	0	72
Control	4.3E+04	2.4E+05	8.6E+05	8.0	9.8-10.4
100 a)	2.0E+04	1.5E+05	1.1E+06	7.8	10.4
100 b)	1.7E+04	5.7E+04	3.3E+05	7.8	8.3

 

 

Table 2: Growth rates and inhibition of growth rates

Concentration [mg/L]	Growth rates after ¿h incubation
	24 [cells/(mL*h)]	48 [cells/(mL*h)]	72 [cells/(mL*h)]
0	0.0611	0.0659	0.0618
100 a)	0.0289	0.0569	0.0649
100 b)	0.0213	0.0361	0.0487
	Inhibition of growth rates after ¿ h incubation
	24 [%]	48 [%]	72 [%]
100 a)	52.7	13.7	-4.9
100 b)	65.2	45.2	21.2

Reference 4

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

20 Jul-23 Jul 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- For analytical measurements a solution was prepared in the same way as test solutions were prepared but without algae
- Samples were taken from all concentrations at 0 and 72 hours

Vehicle:

no

Details on test solutions:

- The poorly water soluble test substance was added to distilled water in a concentration of 1 g/L and stirred for 18 hours. Afterwards the solution was filtrated and the TC-content determined. The TC-content was < 1 mg/L. This solution was used as stock solution and further diluted (differential loading) for the test concentrations

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: CHODAT (86.81 SAG)
- Source (laboratory, culture collection): Institut für Wasser-, Boden- und Lufthygiene, Berlin; afterwards own cultivation
- Method of cultivation: three days prior to test initiation a preculture was cultivated from the stock culture. From this preculture the test cultures were inoculated with a cell density of approx. 20000 cells/mL

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

24 ± 2 °C

pH:

Start of test: 8.1 - 8.3
End of test: 8.6 - 8.7

Nominal and measured concentrations:

- The test solutions were diluted from a stock solution with a concentration of < 1 mg/L. Dilutions and measured concentrations are listed in Table 1

Details on test conditions:

TEST SYSTEM
- Initial cells density: 2 x 10E4 cells/mL
- Control end cells density: 91 x 10E4 cells/mL
- No. of vessels per concentration (replicates): 5-8 replicates
- No. of vessels per control (replicates): 5-8 replicates


GROWTH MEDIUM
- Standard medium used: yes


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


OTHER TEST CONDITIONS
- Light intensity and quality: 8000 Lux, white


EFFECT PARAMETERS MEASURED: Number of cells after 24, 48 and 72 hours
- Determination of cell concentrations: The number of cells were determined photometrically. The absorption at 685 nm was measured and afterwards the absorption values were converted into the parameter "cells/mL"


TEST CONCENTRATIONS
- Spacing factor for test concentrations: < 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

> 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: No effect up to the limit of the water solubility of the test substance was observed.

Details on results:

- Exponential growth in the control: yes

No effect was observed up to the limit of the water solubility of the test substance which was reached under test conditions. The ErC50, ErC10 and ErC90 (0 -72h) are > water solubility under conditions tested.

Table 2: Mean values of cell numbers in dependency of test duration and test substance concentration. The concentrations are based on dilutions (mL/L)

Dilution (mL/L)	Cell numbers (*10^4/mL) during test period
	0h	24h	48h	72h
Control	2	4	24	91
100	2	5	25	92
170	2	5	26	95
300	2	5	28	99
500	2	6	29	101
900	2	7	29	102

Reference 5

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

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

Remarks:

Summary of available data used for the endpoint assessment of the target substance.

Adequacy of study:

weight of evidence

Justification for type of information:

refer to category justification provided in IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 73398-61-5

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 0.449 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

other: TC content

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 73398-61-5

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 10 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 67701-30-8

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 10 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 65381-09-1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 620-67-7

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: RA CAS 620-67-7

Description of key information

No effects on aquatic algae up to the limit of the water solubility of Fatty Acid Glycerides were observed (NOEC ~ water solubility).

Additional information

The hazard assessment is based on the data currently available. New studies (including long-term studies) with the registered substance will be conducted in the future. The finalised studies will be included in the technical dossier as soon as they become available and the hazard assessment will be re-evaluated accordingly.

 

In order to fulfil the standard information requirements, according to Annex XI, 1.5, of Regulation (EC) No 1907/2006, read-across from structurally related substances was conducted. According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", Information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint”.

Four studies with the freshwater algae Scenedesmus subspicatus are available for four different substances (CAS 73398-61-5, CAS 67701-30-8, CAS 65381-09-1 and CAS 620-67-7). In all four static studies with an exposition time of 72 hours no effect on Scenedesmus subspicatus was observed up to the limit of the water solubility of the tested substances.

Three tests were conducted according to EU-Method C.3 and one according to guideline 88/302/EWG, which is equivalent to OECD guideline 201. Two of the tests (CAS 67701-30-8 and CAS 65381-09-1) were conducted with additional consideration of the VCI concept for poorly soluble substances. Thus, two different test solutions were prepared with 100 mg/L: One solution where the test substance was directly weighed into the test vessel and undissolved substance was not removed and a second solution with separation of undissolved substance through filtration (preparation of a Water Accommodated Fraction (WAF)). No effect on the growth rate of Scenedesmus subspicatus was observed in the solutions prepared as WAF and thus, it can be stated that no effect up to the limit of the water solubility of the test substances occurred under conditions tested. The effects observed in the oversaturated solutions with undissolved test substance can therefore be attributed to physical impacts of the undissolved test substances and not to a systemic toxicity of the tested substances. The other two tests (CAS 73398 -61 -5 and CAS 620 -67 -7) used filtered test solutions (WAF) and did not observe effects on Scenedesmus subspicatus up to the limit of the water solubility of the substances either.

Thus, no effect up to the limit of the water solubility for all category members Fatty Acid Glycerides is assumed.