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Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

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Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 20-OCT-2009 to 05-FEB-2010
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: the study was performed according to OECD guideline and GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2010

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
yes
Remarks:
The concentration of NaHCO3 was increased to be twice of that indicated in the Guideline 201. This concentration has been found to be optimal.
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Triglycerides, C12-24, saturated and unsaturated, oxidized
- Substance type: UVCB
- Physical state: liquid
- Stability under test conditions: stable
- Storage condition of test material: at room temperature, protected from light

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Concentrations: 0, 100 mg/L
- Sampling method: data not available
- Sample storage conditions before analysis: data not available

Test solutions

Vehicle:
no
Details on test solutions:
The test item was introduced into the test solutions using aqueous extracts („WAFs“) from the test item as follows: First, a stock solution of the test item was prepared in dichloromethane. An aliquot of this stock solution was given into the the glass vessel for preparation of the aqueous extracts. After evaporation of the solvent the respective amount of ultrapure water was added. Then, the suspension was shaken on a shaking machine for 24 h at ≈130 rpm at room temperature, respectively. During that time an equilibration between the test item and the water was considered to be achieved. After 24h, shaking was stopped, and the suspensions were filtered through glass fibre filter. The eluates („WAFs“) were used directly without any further dilution steps.

Test organisms

Details on test organisms:
TEST ORGANISM
- Common name: green alga
- Strain: Desmodesmus subspicatus CHODAT
- Source (laboratory, culture collection): Sammlung von Algenkulturen, Pflanzen¬physiologi¬sches Institut der Universität Göttingen [SAG], Strain-No. 86.81
- Age of inoculum (at test initiation): 3 days
- Method of cultivation: The algae are cultivated under aseptic conditions.

ACCLIMATION
- Acclimation period:
- Culturing media and conditions (same as test or not): same as test
- Any deformed or abnormal cells observed: data not available

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Post exposure observation period:
none

Test conditions

Hardness:
data not available
Test temperature:
The temperature was constant at 25°C
pH:
See table 1
Dissolved oxygen:
data not available
Salinity:
not applicable (freshwater)
Nominal and measured concentrations:
nominal concentrations: 0 and 100 mg/L
measured concentrations: 0 and 25.2 mg/L at T0, 0 and 21.9 at T72
See table 2
Details on test conditions:
TEST SYSTEM
- Test vessel: 50 mL-glass-cylinders, heat sterilized
- Material, size, headspace, fill volume: filled with 50 mL
- Aeration: In order to assure the input of CO2, the test solutions were stirred by means of a magnetic stirrer for the duration of 15 minutes per hour
- Initial cells density: 2.64*10E3 cells/mL
- Control end cells density: 7.11*10E5 cells/mL
- No. of vessels per concentration (replicates): 7
- No. of vessels per control (replicates): 7

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: no
- Photoperiod: 24/24h under constant light
- Light intensity and quality: illumination rate of >=120 μE/m2s ([~8000 Lux]

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: the increase in biomass was determined using a spectrophotometer after 24, 53.25, and 72 h . As a measure for the biomass the absorbance of the test solutions measured at 578 nm was used.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: not applicable
- Justification for using less concentrations than requested by guideline: limit test at 100 mg/L
- Range finding study
- Test concentrations: 0 1, 10, 100 mg/L
- Results used to determine the conditions for the definitive study: no effect observed at 100 mg/L
Reference substance (positive control):
not specified

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOELR
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 (for algal test): yes
- Observation of abnormalities (for algal test): data not available
Results with reference substance (positive control):
not applicable
Reported statistics and error estimates:
not applicable

Any other information on results incl. tables

The following individual Cell Numbers were obtained:

 Time t0

Control

100 mg/L

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

 

 

2.64*103

2.64*103

Mean Values:

2.64*103

2.64*103

 

 Time t24h

Control

100 mg/L

 

 

2.08*104

2.28*104

 

 

2.47*104

1.30*104

 

 

2.28*104

2.67*104

 

 

2.08*104

1.49*104

 

 

2.47*104

1.49*104

 

 

2.28*104

1.49*104

 

 

2.08*104

1.49*104

Mean Values:

2.25*104

1.75*104

 Time t53.25h

Control

100 mg/L

 

 

2.35*105

2.79*105

 

 

2.37*105

3.13*105

 

 

2.43*105

2.70*105

 

 

2.35*105

2.74*105

 

 

2.58*105

2.85*105

 

 

2.82*105

2.81*105

 

 

2.62*105

2.81*105

Mean Values:

2.50*105

2.83*105

 

 Time t72h

Control

100 mg/L

 

 

9.51*105

1.01*106

 

 

7.84*105

1.20*106

 

 

8.50*105

1.10*106

 

 

7.84*105

1.06*106

 

 

8.28*105

1.12*106

 

 

1.02*106

1.07*106

 

 

8.39*105

1.07*106

Mean Values:

8.65*105

1.09*106

Nominal Concentration of the Test Item

[mg/L]

Growth Rates

(day-1)

Inhibition of the Growth Rate after 72h

[%]

Yield after 72h1)

Inhibition of the Yield after 72h

[%]

Control (0)

1.930

-

8.62*105

-

100

2.008

-4.02)

1.09*106

-26.12)

1)Yield = Cell number at time t72h– cell number at time t0

2)negative values indicate activation of growth

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
The test is considered valid as all conditions for validity were met
Conclusions:
72-hr EL50 (growth rate/yield) > 100 mg/L
72-hr NOELR (growth rate/yield) > 100 mg/L
Executive summary:

The chronic toxicity of“Triglycerides, C12-24, even, saturated and unsaturated, oxidized“ towards algae was tested according to OECD-Guideline No. 201, in the Version dated 23-March 2006. The toxic effect was investigated by determination of the inhibition of the growth rate of the algae and the yield during the exposure period of 72 h. As the test item is poorly water-soluble, it was tested using aqueous extracts (“WAFs”) from up to 100 mg test item/L (final concentration). The main test was performed as a limit test using 100 mg/L as the sole test concentration because within the screening-test there was no negative effect up to that concentration. As a conclusion of the analytical part of this study, recoveries of the concentrations determined after 72h were ≥ 80% of those determined after 72h, and therefore the effective concentrations are based on the nominal concentrations of the WAFs determined.

From the results of the main test, toxic effects were determined with the following values:

On the Basis of the Nominal Loading Rates1)tested

Yield (0 - 72 h)                                

         EC10         >100

         EC20          >100

         EC50          >100

         LOEC          >100

         NOEC          ≥ 100

 

Growth rate (0 - 72h)                     

         EC10         >100

         EC20          >100

         EC50          >100

     LOEC > 100

         NOEC          ≥ 100

     

The test is considered valid as all conditions for validity were met.