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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:
26 Oct - 09 Nov 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
2004
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
Health Care Inspectorate of the Ministery of Health, Welfare and Sport, Utrecht, The Netherlands

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Concentrations: All test concentrations and the control
- Sampling method: Samples were taken at the start of the test and after 24 h from the freshly prepared solutions and at renewal (t= 24 h) and the end of the test from the 24 h old solutions. 2.0 mL were taken from the approximate centre of the test vessels.
- Sample storage conditions before analysis: not applicable

Test solutions

Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method:
Preparation of test solutions started with a loading rate of 100 mg/L applying a three-day period of magnetic stirring to ensure maximum dissolution of the test item in medium. Thereafter, the aqueous Saturated Solution (SS) was collected by filtration through a 0.45 µm membrane filter (RC55, Whatman) and used as the highest test concentration. Lower test concentrations were prepared by subsequent dilutions of the SS in test medium.
- Controls:
Yes
- Eluate: No
- Differnetial loading: No
- Evidence of undissolved material: No; All test solutions were clear and colorless at the end of the preparation procedure.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: water flea
- Strain/clone: Straus, 1820
- Source: In-house laboratory culture with a known history
- Age of parental stock (mean and range, SD): 4 weeks
- Feeding during test: No feeding
- Food type: Suspension of fresh water algae
- Frequency: Daily

ACCLIMATION
- Acclimation period: 4 weeks
- Acclimation conditions (same as test or not): same
- Health during acclimation (any mortality observed): Daphnids originated from a healthy stock, 2nd to 5th brood, showing no signs of stress such as mortality >20%, presence of males, ephippia or discoloured animals and there was no delay in the production of the first brood.

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: < 24 hours, from parental daphnids of more than two weeks old

Study design

Test type:
semi-static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h

Test conditions

Hardness:
180 mg/L expressed as CaCO3
Test temperature:
20 - 21 °C
pH:
7.7 - 8.0 (Control)
7.7 - 8.0 (Test item concentrations)
Dissolved oxygen:
9.0 - 9.2 (Control)
8.5 - 9.1 (Test item concentrations)
Nominal and measured concentrations:
1.0, 10 and 100% of a SS prepared as a concentration of 100 mg/L
0.00040, 0.00078 and 0.0016 mg/L (measured concentration based on TWA)
Details on test conditions:
TEST SYSTEM
Test vessel:
- Type: open
- Material, size, headspace, fill volume: glass, 100 mL, headspace: 20 mL, fill volume: 80 mL
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): After 7 days of cultivation half of the medium was replaced twice a week.
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4 (for highest test item concentration 100 mg/L) and 2 (for the other test item concentrations 1.0 and 10 mg/L)
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: M7 medium (adjusted ISO medium) according to the guideline
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH and dissolved oxygen were measured at the beginning, after 24 h and at the end of the test, for the control and the highest test concentration. Additionally, in the intermediate test concentrations upon renewal of the test solutions. The temperature was measured continuously in a temperature control vessel, beginning at the start of the test and in the fresh and spent test solutions upon renewal.

OTHER TEST CONDITIONS
- Photoperiod: 16 h photoperiod daily

EFFECT PARAMETERS MEASURED: Immobility (including mortality) was measured and recorded at 24 h and at 48 h.

RANGE-FINDING STUDY: no range-finding test was performed
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrations
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 0.002 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Remarks:
filtered solution
Basis for effect:
mobility
Details on results:
- Mortality of control: No
- Abnormal responses: No
- Others: Analytical and biological results are summarized in table 1 and 2 within the section "Any other information on results incl. tables"
Results with reference substance (positive control):
In conclusion, the actual responses in this reference test with K2Cr2O7 are within the ranges of the expected responses at the different concentrations, i.e. the 48 h EC50 was between 0.3 and 1.0 mg/L. Hence, the sensitivity of this batch of D. magna was in agreement with the historical data collected at Charles River Den Bosch. The 48 h EC50 was 0.41 mg/L with a 95% confidence interval between 0.34 and 0.46 mg/L.

Any other information on results incl. tables

Table 1: Analytical Results: Measured Concentrations

Test item 1
% SS prep. at 100 mg/L

Measured concentration (mg/L)

Average exposure concentration (mg/L)

t= 0 h (fresh)

t= 24 h (old)

t= 24 h (fresh)

t= 48 h (old)

1.0

0.00040 2

0.00040 2

0.00040 2

0.00040 2

0.00040

10

0.00040 2

0.00040 2

0.00335

0.00040 2

0.00078

100

0.00354

0.00040 2

0.00332

0.00134

0.0016

1 4,4’-[isopropylidenebis(4,1-phenyleneoxy)]dianiline
2 Taken as half of the limit of detection, i.e. LOD/2 = 0.00040 mg/L.

Table 2: Biological Results: Number of Introduced Daphnids and Incidence of Immobility

Time (h)

Replicate

4,4’-[isopropylidenebis(4,1-phenyleneoxy)]dianiline

% SS prep. at 100 mg/L

Control

1.0

10

100

0

A

5

5

5

5

B

5

5

5

5

C

5

 

 

5

D

5

 

 

5

Total introduced

20

10

10

20

24

A

0

0

0

0

B

0

0

0

0

C

0

 

 

0

D

0

 

 

0

Total immobilised

0

0

0

0

Effect %

0

0

0

0

 

 

 

 

48

A

0

0

0

0

B

0

0

0

0

C

0

 

 

0

D

0

 

 

0

Total immobilised

0

0

0

0

Effect %

0

0

0

0

Table 3: Validity criteria for OECD 202

Criterion from the guideline

Outcome

Validity criterion fulfilled

In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.

No mortality

Yes

The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.

>3 mg/L

Yes

 

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
For further details please refer to “Any other information on results incl. tables”.
Conclusions:
In conclusion, the 48 h EC50 for Daphnia magna exposed to 4,4’-[isopropylidenebis(4,1-phenyleneoxy)]dianiline was beyond the range tested, i.e. exceeded an average concentration of 0.0016 mg/L being considered the maximum soluble concentration of the test item in test medium at a concentration of 100 mg/L.