Fatty acids, C16-18 and C18-hydroxy, oligomeric reaction products with adipic acid, decanoic acid, isooctadecanoic acid, octanoic acid, pentaerythritol and stearic acid

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 Feb - 23 Feb 2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP guideline study with acceptable restrictions: No analytical purity is given. The tested concentration exceeds the water solubility of the test substance. However, no information about undissolved test material is given and it is not stated if undissolved test material was removed from the test vessels.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

921-836-0

EC Number:

921-836-0

IUPAC Name:

921-836-0

Details on test material:

- Name of test material (as cited in study report): Mixed ester of fatty acids, C16 and C16-18 unsatd. with adipic acid and pentaerythritol
- Physical state: yellow liquid
- Analytical purity: not stated
- Lot/batch No.: 140731
- Expiration date of the lot/batch: 12 Dec 2012

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control, 100 mg/L
- Sampling method: Samples were taken from the test vessels at the beginning and at the end of the test.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: 100 mg of the test substance was added to 1000 mL of medium. Then the sample was sonicated for 90 min. So the test was performed at the maximum solubility of the test substance in water.

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: green alga
- Method of cultivation: The algal suspension has been kept in culture medium in sterile 250 mL Erlenmeyer flasks under the following conditions: Temperature: 23 ± 2 °C; Lightning: > 4300 lux; Stirring: steady with electrical stirrer.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Hardness:

not stated

Test temperature:

23.0 ± 2.0 °C

pH:

7.25 - 7.75

Nominal and measured concentrations:

Nominal: 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask
- Initial cells density: 10000 cells/mL
- Control end cells density: 1.8 - 2.5E+06 cells/mL
- No. of vessels per concentration: 6
- No. of vessels per control: 6

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

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: the culture medium (prepared with MilliQ water) has been used as dilution water
- Culture medium different from test medium: no
- Intervals of water quality measurement: The pH was measured at the beginning and at the end of the test. The temperature was monitored during the whole test period.

OTHER TEST CONDITIONS
- Sterile test conditions: yes/no
- Photoperiod: continuous light
- Light intensity and quality: 6000 lux, fluorescent lamp
-other: The test vessels were stirred throughout the test.

EFFECT PARAMETERS MEASURED: Cell concentration is monitored after 24, 48 and 72 h test duration.
- Determination of cell concentrations: counting chamber (Burker chamber)

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

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

Reported statistics and error estimates:

student's t-test

Any other information on results incl. tables

The test exhibited an EC50 of > 100 mg/L (nominal)/ NOEC ≥ 100 mg/L based on growth rate (18% inhibition, see table 2). No effects were observed in the range of water solubility. TOC analysis at 0 and 72 h revealed a stable test substance concentration during the test period ranging from 24.43 mg/L at the beginning to 29.29 mg/L at the end of the test (table 1). All validity criteria are fulfilled (table 3).

Table 1: Concentration of the test substance at the beginning and at the end of the test measured by TOC

Treatment [mg/L]	Time		Stability [%]
	0 h	72 h
100	24.43 mg/L	29.29 mg/L	120

Table 2: Cell concentrations in treatment and control

Test concentration [mg/L]	Replicate	Cell concentration [cells/mL]
		0 h	24 h	48 h	72 h
control	1	1.0E+04	3.8E+04	3.0E+05	2.5E+06
	2	1.0E+04	3.8E+04	3.2E+05	1.9E+06
	3	1.0E+04	3.5E+04	3.2E+05	1.9E+06
	4	1.0E+04	3.7E+04	3.5E+05	1.8E+06
	5	1.0E+04	3.3E+04	3.9E+05	2.2E+06
	6	1.0E+04	3.7E+04	3.5E+05	2.1E+06
100 mg/L	1	1.0E+04	2.8E+04	1.4E+05	8.0E+05
	2	1.0E+04	2.8E+04	2.3+05	7.3E+05
	3	1.0E+04	2.5E+04	1.8+05	7.2E+05
	4	1.0E+04	3.0E+04	1.9E+05	8.3E+05
	5	1.0E+04	2.5E+04	2.2E+05	8.0E+05
	6	1.0E+04	2.8E+04	2.4E+05	7.5E+05

Table 3: Validity criteria

Parameter	days	Result [%]	Validity criteria	passed/ not passed
Growth rate	0-1	1.29	> 0.92	passed
	1-2	2.22		passed
	2-3	1.81		passed
% CVss	0-1	4.22	< 35 %	passed
	1-2	6.52		passed
	2-3	9.63		passed
% CV wp	0-3	2.35	< 7 %	passed