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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:
19 - 21 Sep 2018
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions

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
GLP compliance:
yes (incl. certificate)
Remarks:
Date of certificate: 14.03.2017 (The Department of Health of the Government of the United Kingdom)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
- Concentrations: all concentrations, taken at start and end of the 48 hour exposure period.
- Sampling method: Samples were taken from remaining test media after filling test vessels for 0 hours and pooled replicate flasks for 48 hours.

Test solutions

Vehicle:
yes
Remarks:
Dichloromethane
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Stock solutions were prepared separately by adding the appropriate amount of test substance to solvent (DCM). The total volume of the solvent in the stock solution was 10 mL. The test concentrations were prepared by adding 5 µL of the corresponding stock solution to a total volume of 50 mL of media water.
- Chemical name of vehicle : Methanol for the range finding test and Dichloromethane (DCM) for the definitive test.
- Volume of solvent in solvent control: 5 µL

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Source: From cultures maintained at Chemex Environmental International Ltd since July 2014 and originally sourced from a clone of genotype 5
- Age of parental stock: ≤ 24 hours
- Feeding during test: no

CULTURE CONDITIONS
- Cultured under static conditions
- Temperature: 20 ± 2°C
- Dissolved oxygen: >60% (or 3 mg/L) ASV
- Photoperiod: 16 hours light and 8 hours dark
- Acclimation conditions: same as in test
- Type of food: suspension of Chlorella vulgaris.
- Feeding frequency: Each working day

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Test temperature:
20.7 - 21.9 °C
pH:
7.30 - 7.63
Dissolved oxygen:
6.04 - 7.16 mg/L
Nominal and measured concentrations:
Nominal test concentrations:control, solvent control, 0.134, 0.429, 1.370, 4.380, 14.0 and 45 mg/L
Mean measured concentrations: control, solvent control, 0.059, 0.073, 0.064, 0.085, 0.169 and 0.179 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: Plastic pots (nominal volume 50 mL), covered with a perspex sheet
- Fill volume: 50 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4 reconstituted Daphnia water

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 hours dark cycle

EFFECT PARAMETERS MEASURED : The number of immobilised Daphnia was recorded after 24 and 48-hour exposure.

VEHICLE CONTROL PERFORMED: yes

TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: solvent control (methanol), 0 (control), 0.1, 1.0, 10, 50 mg/L
- Results used to determine the conditions for the definitive study: EC50 (72 h): 10 - 50 mg/L (nominal)
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
4.7 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: (3.5 - 6.4 mg/L; 95% confidence limits)
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.09 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: (0.08 - 0.14 mg/L; 95% confidence limits)
Details on results:
- Mortality of control or solvent control: No
- Other adverse effects control or solvent control: No
Results with reference substance (positive control):
EC50 (24 h): 1.4 mg/L of potassium dichromate (obtained in a separate GLP study conducted from 18 to 20 January 2017)

Reported statistics and error estimates:
ToxCalc™ Version 5.0 “Comprehensive Toxicity Data Analysis and Database Software”, copyright 1994-1996.

Any other information on results incl. tables

Table 1: Cumulative immobilisation

Nominal Concentration

mg/L

Mean measured concentrations mg/L

Number immobilised

% immobilisation

24 hours

48 hours

24 hours

48 hours

0 (Control)

0 (Control)

0

0

0

0

Solvent control (DCM)

Solvent control (DCM)

0

0

0

0

0.134

0.059

0

0

0

0

0.429

0.073

0

0

0

0

1.370

0.064

0

0

0

0

4.380

0.085

6

10

30

50

14

0.179

10

19

50

95

45

0.169

14

20

70

100

Table 2 Biological observations

Nominal Concentration

mg/L

Recorded observations

24 hours

48 hours

0 (Control)

20NS

20NS

Solvent control (DCM)

20NS

20NS

0.134

13NS5Ms2TM

16NS2Ms2TM

0.429

16NS1Ms3TM

9NS9Ms1TMLI1TM

1.370

4NS2Ms14TM

4NS7Ms9TM

4.380

4TM4TMD2DMs4TMDMs

2TM3TMMs1Ms2TMDMs1MsLI1TMLIMs

14

10TMDMs

1MsD

45

6TMDMs

-

Key to comments

S

Sedimentation

Ms

Movement Slower

D

Debris attached to Daphnia

TM

Trapped in Meniscus (mobile)

LI

Lighter Colouration

TI

Trapped in Meniscus (immobile)

NS

No Signs of Abnormality

SM

Daphnia Smaller

-

All Daphnia immobilised

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.

0%

yes

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

>6 mg/L

yes

 

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
see Table 3 at "Any other information on results incl. tables"