Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
19 October 2010 to 21 October 2010
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study conducted under GLP. However, concentration of test substance decreased to below the LOD by the end of the exposure period.

Data source

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

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Deviations:
no
Qualifier:
according to
Guideline:
ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))
Deviations:
no
Qualifier:
according to
Guideline:
other: OECD Series on Testing and Assessment No. 23: Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Name of test material (as cited in study report): MTDID 21721
- Physical state: Colorless liquid
- Analytical purity: 97.21%
- Stability under test conditions: Test substance concentration decreased to below limit of detection within 48-hours of exposure.
- Storage condition of test material: Room temperature in the dark under nitrogen

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Sampling method: Sampling occured at 0 and 48-hours. Three mL singular samples were taken from the center of the test vessels of all test concentrations and the control. Samples were taken in a 10 mL GC vial containing 3 mL of tertiary butyl methyl ether (TBME) and then shaken for 30 seconds prior to storage. At the end of the exposure period, the replicates were pooled at each concentration before sampling. Only the results from the blank control and the 100% water soluble fraction test solutions were reported.
- Sample storage conditions before analysis: Frozen. TMBE was added to fresh samples to ensure stability of TFEE-5 during frozen storage.

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Magnetic stirring for 25 hours was applied to a water solution prepared at a loading rate of 100 mg/L. Final solution was clear and colorless with a precipitate in the form of droplets. The solution was settled for 2 hours after which the water soluble fraction (WSF) was collected by siphoning from the middle. Three lower test concentration solutions were prepared by subsequent dilution of the WSF in test medium.

- Controls: Negative control (dilution water) only

- Evidence of undissolved material (e.g. precipitate, surface film, etc): None noted in final test solutions.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna Straus, 1820
- Source: In-house laboratory culture
- Age at study initiation (mean and range, SD): < 24 hours
- Method of breeding: Acyclical parthenogenesis. Breeding batch started by placing approximately 250 daphnids less than 3 days old into 5 liters of M7 medium in an all-glass culture vessel. Cultures maintained for a maximum age of 4 weeks. After the first 7 days, cultures are renewed by replacement of half of the medium twice weekly. Cultures are maintained at 18 - 22 deg. C and fed daily with a suspension of freshwater algae.
- Feeding during test: None

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Remarks on exposure duration:
Combined limit and range-finding test of a water soluble fraction

Test conditions

Hardness:
180 mg/L as CaCO3
Test temperature:
19.1 - 20.3 deg. C
pH:
7.8 - 8.2
Dissolved oxygen:
8.8 - 9.3 mg/L
Salinity:
not applicable
Nominal and measured concentrations:
Nominal concentrations: Control, 0.10, 1.0, 10, 100% of a water soluble fraction (WSF). Only highest concentration (100% WSF) was analyzed for test substance concentration. At time 0, 100% WSF = 0.175 mg/L; at 48-hours 100% WSF = < LOD (0.14 mg/L). Time Weighted Average exposure concentration over 48-hours was 0.11 mg/L in the 100% WSF solution.
Details on test conditions:
TEST SYSTEM
- Test vessel:100 mL glass beaker
- Type (delete if not applicable): open / closed: Not reported
- Material, size, headspace, fill volume: 80 mL test solution
- Aeration: None
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4 for 100% WSF; 2 for dilutions of WSF.
- No. of vessels per control (replicates): 4
- Biomass loading rate: 16 mL per daphnid

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO M7 medium prepared in reverse osmosis-purified tap water
- Total organic carbon: Not reported
- Particulate matter: Not reported
- Metals: Not reported
- Pesticides: Not reported
- Chlorine: Not reported
- Alkalinity: Not reported
- Ca/mg ratio: 5
- Conductivity: Not reported
- Culture medium different from test medium: No
- Intervals of water quality measurement: Not reported

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16 hours light
- Light intensity: Not reported

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobility, including mortality at 24 and 48 hours

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10-fold
- Range-finding study: yes
- Justification for using less concentrations than requested by guideline: range-finder plus limit test
Reference substance (positive control):
yes

Results and discussion

Effect concentrations
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: The 48-hr EC50 exceeded an average concentration of 0.11 mg/L, the concentration measured in an WSF prepared at a loading rate of 100 mg/L. 10% immobilization seen at highest concentration tested (100% of a water soluble fraction).
Details on results:
- Behavioural abnormalities: None reported
- Mortality of control: None
- Other adverse effects control: None
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Test substance could not be detected in test solutions after 48 hours. The lowest level of detection was 0.14 mg/L. An exposure concentration of 0.11 mg/L in the 100% water soluble fraction was derived as the geometric mean of the initial measured concentration (0.175 mg/L) and half the limit of detection (0.14 mg/L/2).
- Effect concentrations exceeding solubility of substance in test medium: No significant effects were seen at an initial loading of 100 mg/L. The 20 - 30% immobility seen in the lower test concentrations was without a clear concentration-response relationship and therefore was not considered treatment related.
Results with reference substance (positive control):
A reference toxicant test using potassium dichromate was conducted by the testing laboratory 10 - 12 August 2010. The 48-h EC50 was found to be 0.38 mg/L; this value lies between the expected response of 0.3 to 1.0 mg/L. The sensitivity of the tested Daphnia magna was therefore in agreement with the data collected historically at this testing laboratory.
Reported statistics and error estimates:
No statistics. Insufficient effects at limit of water solubility for calculation of EC50

Any other information on results incl. tables

Table 2: Acute immobilization of daphnids after 24 and 48 hours

TFEE-5 Test Concentration - % WSF*

Vessel Number

Number Exposed

Response at 24 hrs

Response at 48 hrs

Number Immobilized

Total %

Number Immobilized

Total %

Control

A

5

0

0

0

0

B

5

0

0

C

5

0

0

D

5

0

0

0.1

A

5

1

30

0

20

B

5

2

2

1.0

A

5

1

20

1

20

B

5

1

1

10

A

5

1

30

1

30

B

5

2

2

100**

A

5

0

10

0

10

B

5

1

1

C

5

0

0

D

5

1

1

*Water soluble fraction prepared at a loading rate of 100 mg/L.

 **Estimated average exposure concentration = 0.11 mg/L

 

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
No daphnids were immobilized in the control; the DO concentration was greater than 3 mg/L in control and test vessels.
Conclusions:
The 48-hour EC50 of TFEE-5 is > 100 mg/L (nominal concentration of water soluble fraction)
Executive summary:

The acute toxicity of TFEE-5 to Daphnia magna was evaluated according to OECD TG202. Due to the low water solubility of this substance, toxicity was determined in a combination range-finder/ limit test using water soluble fractions. Test concentrations were 0.1, 1.0, 10, and 100% of a water soluble fraction prepared at 100 mg/L. No statistically significant immobilization or mortality was observed after 48 hours of exposure to 100% of the water soluble fraction. Therefore, the 48-hour EC50 is > 100 mg/L. TFEE-5 is not acutely toxic to Daphnia magna according to GHS criteria.

The study was performed in accordance with internationally-accepted test guidelines and Good Laboratory Practice standards. However, test substance concentration was not maintained throughout the 48-hour exposure period. Therefore, this study is reliable with restrictions.

Results Synopsis

Test Type: static

EC50: > 100 mg/L       95% C.I.: Not applicable

NOEC: 100 mg/L       Probit slope: not applicable