Alcohols, C10-16, ethoxylated, sulfates, mono(hydroxyethyl)ammonium 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:

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

Adequacy of study:

key study

Justification for type of information:

Refer to the analogue approach justification provided in section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

2.81 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 2.65 - 2.99

Remarks:

Source, key, 157627-92-4 (C12-13, 0.85EO), P&G, 2000

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

1.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

biomass

Remarks on result:

other: 95% CI: 1.19 - 1.66

Remarks:

Source, key, 157627-92-4 (C12-13, 0.85EO), P&G, 2000

Duration:

72 h

Dose descriptor:

other: EC8

Effect conc.:

0.42 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other:

Remarks:

Source, key, 157627-92-4 (C12-13, 0.85EO), P&G, 2000

Duration:

72 h

Dose descriptor:

other: EC21

Effect conc.:

0.42 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

biomass

Remarks on result:

other:

Remarks:

Source, key, 157627-92-4 (C12-13, 0.85EO), P&G, 2000

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 - 28 Oct 1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

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

Remarks:

incl. GLP compliance statement by the study director

Analytical monitoring:

yes

Details on sampling:

- Concentrations: samples were taken from all test concentrations at the start of the test and after 24, 48 and 72 hours
- Sampling method: sampling amount was 25 ml for test solutions =< 1 mg/L, 15 ml for test solutions =< 20 mg/L and 5 mL for test solutions >20 mg/L. All replicate samples were taken in polyethylene bottles
- Replica samples: 2 of each test vessel and test concentration
- Sample storage conditions before analysis: in the deepfreezer (<-15 °C) until analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: a stock solution of 1.0 g a.i./L was prepared by dissolving 663.2 mg of the test substance in 500 ml deionised water. The stock solution was stirred at room temperature for at least 1 hour. The different concentrations were prepared by appropriate dilution of the stock solution with demineralised water. Stock solutions were mixed 1:1 with the algal suspension

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: green algae
- Source (laboratory, culture collection): LISEC Laboratory culture (ex. CCAP 278/4)
- Age of inoculum (at test initiation): 3 days
- Cell density of preculture: 2.54 x 10E+06 cells/mL

ACCLIMATION
- Culturing media and conditions (same as test or not): same as test
- Any deformed or abnormal cells observed: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

22.7 - 23.5 °C

pH:

7.64 - 9.2

Nominal and measured concentrations:

Nominal test concentrations: 0, 0.625, 1.25, 2.5, 5 and 10 mg/L
Measured concentrations (geometric mean): 0.01, 0.42, 1.03, 1.79, 2.99 and 6.19 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass flask covered with a plastic stop
- Fill volume: 100 mL of test solution in each flask (200 mL for the sampling test vessel)
- Shaking: in order to keep the algae in suspension and facilitate transfer of CO2, the controls and test solutions were placed on a rotative plate and continously shaken
- Initial cells density: 1 x 10E+04 cells/mL
- Control end cells density: 43.5 x 10E+04 cells/mL
- No. of vessels per concentration: 4 replicates
- No. of vessels per control (only algae and medium): 4 replicates
- No. of vessels per reference of each test concentration (algal medium and test substance): 1 replica

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

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: an algal suspension being a two times concentrated nutrient and algal solution is used to dilute a same volume of control solution or test solution
- Ca/mg ratio: CaCL2.2H2O - 18 mg/L / MgCL2.6H2O - 12 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH and temperature were measured daily (0, 24, 48 and 72 h)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: continuous uniform illumination was provided by Philips TL-33 lamps
- Light intensity and quality: 6500 Lux at the surface of the test solution. Illumination sources were placed around a rotative plate, with controls and test vessels fixed at the outer side of the plate

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: the absorbancy of each test solution was measured daily using a UNICAM UV2 Spectrophotometer (720 nm, cuvettes with light paths of 5 cm)

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

2.81 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: 95% CI: 2.65 - 2.99

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

1.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

biomass

Remarks on result:

other: 95% CI: 1.19 - 1.66

Duration:

72 h

Dose descriptor:

other: EC8

Effect conc.:

0.42 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

other: EC21

Effect conc.:

0.42 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

act. ingr.

Basis for effect:

biomass

Details on results:

- Exponential growth in the control: yes
- Observation of abnormalities: none

Reported statistics and error estimates:

The EC50 and NOEC values were calculated by Dunnett's t-test (SAS Procedure GLM).

Table 1: Measured absorbencies of the test solutions

Concentration (measured; geometric mean)		Absorbency at time (h)
		0	24	48	72
0 mg/L	A	0.006	0.025	0.087	0.257
	B	0.005	0.025	0.087	0.261
	C	0.006	0.025	0.087	0.265
average		0.006	0.025	0.087	0.261
standard deviation		0.001	0.000	0.000	0.004
0.42 mg/L	A	0.006	0.022	0.072	0.203
	B	0.006	0.021	0.07	0.201
	C	0.006	0.021	0.071	0.209
average		0.006	0.021	0.071	0.204
standard deviation		0.000	0.001	0.001	0.004
1.03 mg/L	A	0.006	0.020	0.061	0.170
	B	0.006	0.018	0.052	0.144
	C	0.006	0.021	0.061	0.166
average		0.006	0.020	0.058	0.160
standard deviation		0.000	0.002	0.005	0.014
1.79 mg/L	A	0.006	0.017	0.041	0.095
	B	0.006	0.015	0.039	0.105
	C	0.006	0.017	0.041	0.105
average		0.006	0.016	0.040	0.102
standard deviation		0.000	0.001	0.001	0.006
2.99 mg/L	A	0.006	0.011	0.013	0.033
	B	0.006	0.010	0.012	0.031
	C	0.006	0.010	0.013	0.030
average		0.006	0.010	0.013	0.031
standard deviation		0.000	0.001	0.001	0.002
6.19 mg/L	A	0.006	0.008	0.002	0.01
	B	0.006	0.008	0.001	0.01
	C	0.006	0.008	0.001	0.009
average		0.006	0.008	0.001	0.010
standard deviation		0.000	0.000	0.001	0.001

Table 2: Calculation of area, average growth rate and % inhibition

Concentration [mg/L]	area (growth)	inhibiton (%) growth	growth rate	inhibition (%) growth rate
0	5.48		0.053
0.625	4.31	21.4	0.049	8.0
1.25	3.61	34.1	0.046	13.1
2.5	2.22	59.5	0.039	26.2
5	0.57	89.6	0.023	56.9
10	-0.02	100.4	0.007	87.6

Table 3: Analytical results of the water samples at the beginning of the test and after 72 h

	sampling time [h]
	0		72
Nominal test concentration a.i. [mg/L]	Measured a.i concentration [mg/L]	Corrected measured a.i. concentration [mg/L]	Measured a.i concentration [mg/L]	Corrected measured a.i. concentration [mg/L]
0	<0.026	<0.029	0.1	0.1
0.625	0.5	0.5	0.3	0.3
1.25	1.1	1.2	0.6	0.7
2.5	2.1	2.3	1.3	1.4
5	4.3	4.7	1.2	1.3
10	8.6	9.5	2.6	2.9

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

30 Aug - 02 Sep 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: 86.81 SAG
- Source (laboratory, culture collection): Institut für Wasser-, Boden- und Lufthygiene, Berlin and subsequently in-house breeding
- Age of inoculum (at test initiation): 3 days

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

24 +/- 2 °C

pH:

Test start: 8.4 - 8.5
Test end: 7.6 - 9.4

Nominal and measured concentrations:

nominal: 1, 2, 4, 8, 16 and 32 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: Erlenmeyer flasks
- Aeration: yes
- Initial cells density: 20000 cells/mL
- Control end cells density: 970000
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (replicates): 8


OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: continuous illumination
- Light intensity and quality: approximately 8000 Lux, white


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: photometer at 685 nm

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

14 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

4.3 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Reported statistics and error estimates:

From the comparison of the areas under the growth curves, the percentage inhibition rates are calculated for each concentration.
The expect probits for each concentration were calculated by probit transformation of the percentage inhibition rates over the regression line. This probits are the basis for the following probit analysis according to Cavalli-Sforza.

	Cell number (x 10^4cells/mL)
Concentration [mg/L]	Test period (h)
	0 h	24 h	48 h	72 h
Control	2	6	25	97
1	2	7	25	93
2	2	8	25	83
4	2	6	23	77
8	2	6	16	49
16	2	4	7	11
32	2	3	4	3

Reference 4

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

12 - 15 Jul 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Qualifier:

according to guideline

Guideline:

other: EU-Guideline 92/69 EWG

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Strain: 86.81 SAG
- Source (laboratory, culture collection): originally obtained from Institut für Wasser-, Boden- und Lufthygiene, Berlin. In-house culture
- Age of inoculum (at test initiation): 3 days

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

24 °C +/- 2 °C

pH:

Test start: 7.9 - 8.1
Test end: 7.2 - 8.8

Nominal and measured concentrations:

nominal: 0.7, 1.5, 3, 6, 12 and 24 mg/L
mean measured: 0.93, 1.8, 3.2, 6.3, 13.8 and 24.5 mg/L (based on a-WAS)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: Erlenmeyer flasks
- Aeration: yes
- Initial cells density: 20000 cells/mL
- Control end cells density: 730000 cells/mL
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (replicates): 8


GROWTH MEDIUM
- Standard medium used: yes according to EU-Guideline 92/69/EWG


OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Photoperiod: continuous illumination
- Light intensity and quality: approximately 8000 Lux (white)



EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: spectrophotometer (wave length: 685 nm)

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

27 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: a-WAS concentration

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

27.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: endpoint re-calculated from the data given in the study: endpoint in a-WAS and purity of the test material

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.93 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

other: a-WAS concentration

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.95 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Remarks on result:

other: endpoint re-calculated from the data given in the study: endpoint in a-WAS and purity of the test material

Details on results:

- Exponential growth in the control (for algal test): yes

Reported statistics and error estimates:

The EC-values were determined by probit transformation of percental growth inhibition values using regression analysis. Based on these values an additional probit analysis according to Cavalli-Sforza were conducted.

Concentration [mg/L]	Cell density (x 10^4cells/mL)
	Test duration
	0 h	24 h	48 h	72 h
Control	2	5	18	73
0.93	2	5	19	73
1.8	2	5	17	58
3.2	2	5	16	59
6.3	2	5	16	53
13.8	2	4	12	19
24.5	2	4	13	14

Description of key information

72h EC50 (Pseudokirchneriella subcapitata, growth rate) = 2.81 mg a.i./L (measured, OECD 201)

72h EC8 (Pseudokirchneriella subcapitata, growth rate) = 0.42 mg a.i./L (measured, OECD 201)

Additional information

The assessment is based on the data currently available. New studies, based on the category review and the final decisions issued for some of the category substances, which are also relevant for this assessment, are currently being conducted. The hazard assessment with respect to aquatic toxicity will be updated once all ongoing studies have been finalised.

For aquatic algae no studies on toxic effects of AES(C10-16, 1-2.5 EO)MEA (CAS 157627-92-4) are available. Therefore, a read-across approach from similar AES mixtures was applied.

The key study was performed according to OECD guideline 201 in compliance with GLP requirements (P&G, 2000). In this study green algae (Pseudokirchneriella subcapitata) were exposed to AES(C12-13, 0.85EO)MEA (CAS 157627-92-4). Based on growth inhibition an EC50 (72h) of 2.81 mg a.i./L (measured) and an EC8 (72h) of 0.42 mg a.i./L (measured) was determined.

This result is confirmed by two further GLP studies conducted according to OECD guideline 201 with Scenedesmus subspicatus as test species. For the test item AES(C12-14, 1-2.5EO)MIPA (CAS 1187742-72-8) an EC50 (72 h) of 14 mg a.i./L (nominal) was observed based on growth rate. The corresponding NOEC (72 h) was 2 mg a.i./L (nominal) (Sasol, 1999). For AES(C12-14, 1-2.5EO)Na (CAS 68891-38-3) an EC50 (72 h) of 27.7 mg a.i./L (measured) was determined and the corresponding NOEC (72h) was 0.95 mg a.i./L (measured) (Sasol, 1993).