(2-hydroxy-3-sulphopropyl)dimethyl[3-[(1-oxododecyl)amino]propyl]ammonium hydroxide

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

5 december 2008 - 20 january 2009

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Despite the lack of analytical monitoring data, it can be reasonably assumed that the test concentrations remained stable over the test duration from the analytical measurements reported in the long-term toxicity test to Daphnia magna performed on a structural analogue substance (Höger, 2013).

Qualifier:

according to guideline

Guideline:

ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonema costatum and Phaeodactylum tricornutum)

Deviations:

not specified

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: the test solutions were prepared by dilution series from an initial 1000mg/L stock solution and without any organic solvent.
- Controls: treated seawater without test item.
- Reference vessels: prepared from a main stock of 100 mg/L of 3,5-dichlorophenol.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): none.

Test organisms (species):

Skeletonema costatum

Details on test organisms:

TEST ORGANISM
- Common name: Skeletonema costatum.
- Culture number: C5B2A.
- Method of cultivation: pre-cultures in the exponential growth phase were prepared from stock laboratory cultures by inoculating treated seawater with nutrient medium (culture medium) to a cell density of approximately 2 x 10E3 to 10E4 cells per millilitre. The pre-cultures were incubated at approximately 20 +/- 2°C under constant illumination for 3 days +/- 1 day, and where uses as the inoculum source for the test.

ACCLIMATION
- Acclimation period: not specified.
- Culturing media and conditions: see method of cultivation above.
- Any deformed or abnormal cells observed: data not available.

Test type:

static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

No data

Test temperature:

19.1 - 21.6 °C

pH:

Test item vessels: 8.13 - 8.18 (at 0h)
Control vessels: 8.11 - 9.10 (during the test)

Dissolved oxygen:

No data

Salinity:

36 ppt at 0h (in diluent water)

Nominal and measured concentrations:

Nominal concentrations: 10, 18, 32, 56 and 100 mg/L (test item)

Details on test conditions:

TEST SYSTEM
- Test vessel:
-- Type: borosilicate glass conical flasks;
-- Material, size, headspace, fill volume: 100-mL flasks, filled with 80mL of test medium seawater.
- Agitation: during the test, the test solutions were continuously stirred by orbital shaker.
- Renewal rate of test solution (frequency/flow rate): a static, non-renewal exposure system was used.
- Initial cells density: 10000 algal cells per mL of test medium.
- No. of vessels per concentration (replicates): 2.
- No. of vessels per control (replicates): 4.

TEST MEDIUM / WATER PARAMETERS
Culture medium was prepared from natural seawater supplied by pump from Scapa Flow, Orkney. All seawater was UV sterilised and filtered to 0.2 µm. The filtered treated seawater was enriched with nutrients and vitamins in accordance with ISO Guidelines. The salinity of the enriched natural seawater at 0h was 36 °/oo +/- 4°/oo.

OTHER TEST CONDITIONS
- Sterile test conditions: yes.
- Adjustment of pH: at 0h for the test item concentration of 100 mg/L.
- Photoperiod: continuously illuminated.
- Light intensity and quality: the measured light intensity (7160 - 8900) was achieved by four 40W tubes mounted at a distance of approximatively 40 cm directly above the test area. Light intensity values were measured daily during the test.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: Counts of algal cell numbers were carried out daily by Fluorometer measurements. Three readings were performed on each test vessel.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: not stated.
- Range finding study: yes.
- Test concentrations: 1 - 10 - 100 - 1000 mg/L (test item).
- Results used to determine the conditions for the definitive study: yes.

Reference substance (positive control):

yes

Remarks:

3,5 Dichlorophenol

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

16.89 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% CL = 15.08-18.65 mg/L

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 5.1 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 3 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth rate

Details on results:

The following validity criteria were fulfilled:
- the biomass in the control cultures has increased exponentially by a factor greater than 16 within the 72-hour test period;
- test conditions (pH, temperature) were maintained during the test.

There is a lack of information of data relating to the analytical monitoring showing that the concentrations of the test item were maintained during the test. However, according to the long-term toxicity test to Daphnia performed on a very similar substance, the substance is stable during 48 hours. Thus, we can consider that in a short-term study, the substance is also stable.

Results with reference substance (positive control):

For evaluation of the quality of the aquatic organisms and the experimental conditions, 3,5-dichlorophenol was tested as a positive control.
72h EC50 = 2.19 mg/L (with 95% confidence limits : 2.03 - 2.34 mg/l)
(See results on tables 2 and 5 below)

Reported statistics and error estimates:

The raw data for each duplicate vessel and time period were averaged, to give values for each concentration of cell volume. Growth rate was calculated on the basis of these measurements. Daily intrinsic growth rate was calculated for each duplicate for each time period using an exponential model :
Nt = N0.ekt where :
Nt : volume or number at time t
N0 = volume or number at beginning of test
t = time in days
k = growth rate (d -1)

The average value of k for each time interval was calculated for each concentration. Since the criterion of effect was the concentration causing 50% reduction in growth rate with respect to the controls, the response for each concentration was estimated from . Effect = 1- (control k/treatment k).

The resulting values represent proportional reduction in growth rate. The EC50 for each time interval and the 72h EC90 and NOEC values were calculating using an appropriate statistical method from the ToxCalc Version 5 software.

Table 4 - Fluorescence measurements (ppb) in test vessels after 24, 48 and 72h

Concentration (mg/L)	24h	48h	72h
10a	0.161	3.414	34.907
10a	0.178	3.367	34.975
10a	0.135	3.351	34.867
10b	0.183	3.875	36.232
10b	0.200	3.879	36.273
10b	0.205	3.849	36.177
18a	0.033	0.219	3.383
18a	0.034	-	3.376
18a	0.045	-	3.341
18b	0.040	0.199	4.232
18b	0.046	-	4.157
18b	0.042	-	4.129
32a	0.058	0.011	0.172
32a	0.058	-	-
32a	0.060	-	-
32b	0.039	0.009	0.199
32b	0.040	-	-
32b	0.040	-	-
56a	0.028	0.018	0.472
56a	0.036	-	-
56a	0.022	-	-
56b	0.048	0.033	0.414
56b	0.005	-	-
56b	0.039	-	-
100a	0.016	0.014	0.113
100a	0.001	-	-
100a	0.014	-	-
100b	0.022	0.031	0.127
100b	0.016	-	-
100b	0.014	-	-

 

Table 5 - Fluorescence measurements (ppb) in control and referencesubstance (3,5 -DCP) after 72h

Replicate	72h			Rep growth	Mean growth
	Measurement 1	Measurement 2	Measurement 3
Control 1	47.406	47.489	44.259	1.00	1.00
Control 2	44.461	44.858	45.081	1.03
Control 3	55.560	55.454	55.601	0.98
Control 4	49.561	49.809	49.812	0.99
1.0a	42.755	50.684	51.023	1.00	0.99
1.0b	46.574	46.256	46.355	0.99
1.8a	13.181	13.169	13.138	0.71	0.69
1.8b	11.148	11.116	11.037	0.67
3.2a	0.608	0.585	0.566	0.02	0.01
3.2b	0.473	0.479	0.478	0.00

 

Table - Coefficient of variation at 24, 48 and 72h (%)

24 h control CV %	7.59
48 h control CV %	1.53
72 h control CV %	2.10

Validity criteria fulfilled:

yes

Conclusions:

The test item exhibited adverse effects on Skeletonema costatum at nominal concentrations of 18 mg/L and higher. The 72h-EC50 (growth rate) value was determined to be 16.89 mg/L (corresponding to 5.1 mg active content/L) while the 72h-NOEC value was determined to be 10 mg/L (corresponding to 3 mg active content/L).

Executive summary:

The toxicity of the REACh substance (2-Hydroxy-3-sulphopropyl) dimethyl[3-[(1-oxododecyl) amino]propyl]ammonium hydroxide (EC 242-893-1) was investigated in a GLP-compliant study performed with the marine algal species Skeletonema costatum in accordance with ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonema costatum and Phaeodactylum tricornutum). The test item exhibited adverse effects on Skeletonema costatum at nominal concentrations of 18 mg/L and higher. The 72h-EC50 (growth rate) value was determined to be 16.89 mg/L (corresponding to 5.1 mg active content/L) while the 72h-NOEC value was determined to be 10 mg/L (corresponding to 3 mg active content/L).

Description of key information

The toxicity of the REACh substance (2-Hydroxy-3-sulphopropyl) dimethyl[3-[(1-oxododecyl) amino]propyl]ammonium hydroxide (EC 242-893-1) was investigated in a GLP-compliant study (Hudson, 2009) performed with the marine algal species Skeletonema costatum in accordance with ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonema costatum and Phaeodactylum tricornutum). The test item exhibited adverse effects on Skeletonema costatum at nominal concentrations of 18 mg/L and higher. The 72h-EC50 (growth rate) value was determined to be 16.89 mg/L (corresponding to 5.1 mg active content/L) while the 72h-NOEC value was determined to be 10 mg/L (corresponding to 3 mg active content/L).

NB. In case the solid content of the test item was not reported in a study report, ECx values were expressed in active content. If relevant, these values were used for the chemical safety assessment (worst-case values).

Key value for chemical safety assessment

EC50 for marine water algae:

5.1 mg/L

EC10 or NOEC for marine water algae:

3 mg/L

Additional information

The toxicity to aquatic (marine) algae of the substance EC 242-893-1 was investigated in a GLP-compliant study (Hudson, 2009) performed in accordance with standard methods, without deviations. The study is considered as reliable (Klimisch 2) and was selected as key study for the endpoint.