4-chloromethyl-4''-ethyl-2'-fluoro-[1,1':4',1''-terphenyl]

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-08-29 to 2017-09-01

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Details on sampling:

The test item concentration in the reconstituted water was not quantified at the start and the end of this study. Because of the low water solubility (0.00306 mg/L), the compound cannot be detected with standard analytical methods and the development of an analytical method with a sufficiently low detection and quantification limit is complex.
Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification.

Vehicle:

yes

Remarks:

Reconstituted water (ELENDT M4 medium)

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A stock preparation with a test item concentration of 100 mg/L was freshly prepared. For that purpose, the test item was weighed in a calibrated flask and vehicle was added. The preparation was stirred with a magnetic stirrer for 24 hours. Then the formulation was passed through a filter membrane (pore size: 0.2 µm). The filtrate was used for the study. The pH was not adjusted.
- Controls: Vehicle control was done.
- Chemical name of vehicle: Reconstituted water (ELENDT M4 medium)
- Concentration of vehicle in test medium: Not applicable as test medium was used as vehicle.
- Test concentration separation factor: Only saturation concentration (nominal 100 mg/L) was used in the limit test.
- Evidence of undissolved material: No

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia
- Strain/clone: Daphnia magna Straus
- Age at study initiation (mean and range, SD): not older than 24 h
- Method of breeding: Daphnids are kept individually in 100 mL glass vessels containing approximately 60 mL reconstituted water (ELENDT M4 medium) at a water temperature of 20 ± 2°C and a 16 hour light and 8 hour dark regime to ensure similar conditions as in the experiment. The parental daphnids are fed ad libitum with unicellular green algae Pseudokirchneriella subcapitata three times per week. Offspring are removed from the vessels at least twice per week.
- Source: the parent generation was originally bred by IBACON GmbH, Germany
- Age of parental stock (mean and range, SD): max. 6 weeks old
- Feeding during test: Daphnids were not fed during the experimental phase.

ACCLIMATION
- Acclimation period: No. To avoid an acclimation phase before start of the study, reconstituted water and other similar conditions were used during culture as well as during the study.

QUARANTINE (wild caught): not applicable

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

237 mg CaCO3/L

Test temperature:

20.3 - 20.9 °C

pH:

7.72 - 7.88

Dissolved oxygen:

8.25 - 8.74 mg/L

Salinity:

not applicable

Conductivity:

674 µS/cm

Nominal and measured concentrations:

Nominal 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass test tubes
- Type: open
- Material, size, headspace, fill volume: 20 mL glass test tubes containing 20 mL medium
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water (ELENDT M4 medium according to OECD 202). Please refer to “Any other information on materials and method” for details on medium composition.
- Total organic carbon: no data
- Particulate matter: no data
- Metals: refer to “Any other information on materials and method”
- Pesticides: no data
- Chlorine: refer to “Any other information on materials and method”
- Alkalinity: no data
- Ca/mg ratio: no data
- Culture medium different from test medium: no
- Intervals of water quality measurement: at start and end of exposure

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16h light / 8h dark
- Light intensity: The mean light intensities were 636 Lux and 622 Lux prior to and at the end of the exposure period, respectively.

EFFECT PARAMETERS MEASURED: Immobilisation (daily)

VEHICLE CONTROL PERFORMED: yes, as reconstituted water was used as vehicle

RANGE-FINDING STUDY
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: no immobilisation observed at 100 mg/L

Reference substance (positive control):

no

Remarks:

No positive control used in this study. The accuracy and reliability of the test method is demonstrated periodically as recommended by guidelines with potassium dichromate.

Duration:

24 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: EC50 > 0.00306 mg/L (limit of solubility)

Key result

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: EC50 > 0.00306 mg/L (limit of solubility)

Details on results:

An aqueous solution of nominal 100 mg/L of the test item revealed no aquatic toxicity in the test system.

The 48h EC50 exceeded the water solubility of 0.00306 mg/L (nominal >100 mg/L) and, thus, could not be determined in this study.

- Behavioural abnormalities: no
- Other biological observations: no
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: No effects were observed up to the solubility limit.

Results with reference substance (positive control):

A separate study was conducted to determine the effect of the positive control substance Potassium dichromate on the immobilization of Daphnia magna in order to check the sensitivity of the test system as recommended by guidelines (Council Regulation (EC) No. 440/2008 and OECD Guideline No. 202). Juvenile daphnids were exposed to different concentrations of Potassium dichromate (0, 0.31, 0.46, 0.69, 1.02 and 1.52 mg/L) in an open static system. 20 daphnids, divided into four replicates, each with five animals were used per concentration and control. The daphnids were observed for immobilization after 24 and 48 hours of exposure. No effect on the mobility of the daphnia was observed at the two lowest concentrations of 0.31 mg/L and 0.46 mg/L. A concentration dependent immobilization was observed at concentrations of 0.69 to 1.52 mg/L.
EC50 values with 95 % confidence intervals:
24h EC50 1.13 mg/L (0.98 – 1.34 mg/L)
48h EC50 0.74 mg/L (0.66 – 0.82 mg/L)
Under the conditions of the present study, the Potassium dichromate showed a 24h EC50 value of 1.13 mg/L which is within the range of the published data of 0.6 to 1.7 mg/L (Council Regulation (EC) No. 440/2008) and 0.6 to 2.1 mg/L (OECD Guideline No. 202).
Therefore, this study confirms the sensitivity and reliability of the test system used in the test facility.

Table 2: Immobilisation of daphnids

Nominal concentration [mg/L]	Number of daphnids immobilized / exposed		% of daphnids immobilized
	24 hours	48 hours	24 hours	48 hours
Control	0/20	0/20	0 %	0 %
100	0/20	0/20	0 %	0 %

Validity criteria fulfilled:

yes

Conclusions:

No adverse effects on daphnids were observed up to the water solubility of the test item. Thus, an aqueous solution of nominal 100 mg/L of the test item revealed no toxicity to daphnids. The 48h EC50 was > 0.00306 mg/L (nominal > 100 mg/L).

Executive summary:

A study according to OECD TG 202 was conducted to determine the effect of the test item on the immobilization of Daphnia magna. Juvenile daphnids were exposed to a nominal test item concentration of 100 mg/L (limit test) in an open static system. 20 daphnids, divided into four replicates, each with five animals were used in the test item group and the control group. The daphnids were observed for immobilization after 24 and 48 hours of exposure. The test item concentration in the reconstituted water was not quantified at the start and the end of this study. Because of the low water solubility (0.00306 mg/L), the compound cannot be detected with standard analytical methods and the development of an analytical method with a sufficiently low detection and quantification limit is complex. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification. No effect on the mobility of the daphnia was observed up to the water solubility of the test item at a nominal concentration of 100 mg/L.

For the test item the following EC50 values were determined:

EC50 (24h) > 100 mg/L (nominal); > 0.00306 mg/L (LOD)

EC50 (48h) > 100 mg/L (nominal); > 0.00306 mg/L (LOD)

Under the conditions of the present study, an aqueous solution of nominal 100 mg/L of the test item revealed no toxicity to daphnids. The 48h EC50 was > 0.00306 mg/L (nominal > 100 mg/L) and, thus, could not be determined.

Description of key information

No adverse effects on daphnids were observed up to the water solubility of the test item. Thus, an aqueous solution of nominal 100 mg/L of the test item revealed no toxicity to daphnids. The 48h EC50 was > 0.00306 mg/L (nominal > 100 mg/L) (reference 6.1.3-1).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L

Additional information

A study according to OECD TG 202 was conducted to determine the effect of the test item on the immobilization of Daphnia magna. Juvenile daphnids were exposed to a nominal test item concentration of 100 mg/L (limit test) in an open static system. 20 daphnids, divided into four replicates, each with five animals were used in the test item group and the control group. The daphnids were observed for immobilization after 24 and 48 hours of exposure. The test item concentration in the reconstituted water was not quantified at the start and the end of this study. Because of the low water solubility (0.00306 mg/L), the compound cannot be detected with standard analytical methods and the development of an analytical method with a sufficiently low detection and quantification limit is complex. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification. No effect on the mobility of the daphnia was observed up to the water solubility of the test item at a nominal concentration of 100 mg/L.

For the test item the following EC50 values were determined:

EC50 (24h) > 100 mg/L (nominal); > 0.00306 mg/L (limit of solubility)

EC50 (48h) > 100 mg/L (nominal); > 0.00306 mg/L (limit of solubility)

Under the conditions of the present study, an aqueous solution of nominal 100 mg/L of the test item revealed no toxicity to daphnids. The 48h EC50 was > 0.00306 mg/L (nominal > 100 mg/L) and, thus, could not be determined.