Bisbenzimidazo[2,1-b:1',2'-j]benzo[lmn][3,8]phenanthroline-6,9-dione

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

according to OECD 202 and GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Details on test solutions:

Preparation of the The saturated solution (1.00 mg/L test item was weighed out) was
saturated solution prepared with dilution water two days prior to the start of the exposure (0 h).

Treatment
The test item was dispersed in the dilution water by stirring with approximately 1100 rpm for 48 h at room temperature. After completion of stirring, the test item dispersion was centrifuged for 10 minutes at 18533 g at 20 °C to remove undissolved test item and to achieve the saturated solution.

Test concentration
The effects of the saturated solution of the test item were tested in a limit test.

Control
Dilution water without test item exposed under the same conditions as the test groups.

Test method
Static

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Clone 5
- Source:
Origin: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu)
Breeder: DR.U.NOACK-LABORATORIEN, Käthe-Paulus-Str. 1, 31157 Sarstedt, Germany
- Age at study initiation (mean and range, SD): 2 to 24 h old daphnids from a healthy stock were used for the study
- Method of breeding:
Culture: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 +- 2°C, in an incubator, 16 h illumination; light intensity
of max. 20 µE x m-2 x s-1
Culture medium: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L
Cultur feeding: At least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and
Desmodesmus subspicatus, with an algae cell density of > 106 cells/mL
- Feeding during test: No feeding

ACCLIMATION
- Acclimation period: At least 2 h in dilution water.
- Acclimation conditions (same as test or not): Same as test conditions.
- Health during acclimation (any mortality observed): No mortality observed.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

260 mgCaCO3/L

Test temperature:

19 - 20°C, constant within ± 1°C

pH:

pH at the Start of the Exposure (0 h)
(measured in one additional replicate of the saturated solution and the control)

Nominal loading
of the test item
[mg/L] pH-value
1.00 (Saturated solution) 7.50
Control 7.66



pH at the End of the Exposure (48 h)
(measured in all replicates of the saturated solution and the control)

Nominal loading
of the test item
[mg/L] pH-values
Replicates
1 2 3 4
1.00 (Saturated solution) 7.47 7.48 7.52 7.54
Control 7.50 7.49 7.50 7.52

Dissolved oxygen:

O2-concentration at the Start of the Exposure (0 h)
(measured in one additional replicate of the saturated solution and the control)

Nominal loading
of the test item
[mg/L] DissolvedO2-concentration[mg/L]
1.00 (Saturated solution) 8.39
Control 8.45


O2-concentration at the End of the Exposure (48 h)
(measured in all replicates of the saturated solution and the control)

Nominal loading
of the test item
[mg/L] DissolvedO2-concentration[mg/L]
Replicates
1 2 3 4
1.00 (Saturated solution) 8.01 8.13 8.07 8.18
Control 7.98 8.01 8.06 8.04

Nominal and measured concentrations:

Limit concentration: saturated solution (nominal loading level 1.00 mg/L)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (4 cm ID x 7 cm H), 50 mL capacity, loosely covered with watch glasses
- Aeration: None
- 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: ISO Test water, according to OECD 202, Annex 3
Component Concentration [mg/L]
KCl 5.76
NaHCO3 64.8
CaCl2 x 2 H2O 294
MgSO4 x 7 H2O 123

- Water Quality Parameters of the Dilution Water prior to the Start of the Exposure (0 h):
pH-value DissolvedO2-concentration[mg/L] Temperature[°C] Conductivity[µS/cm] Total hardness [mg CaCO3/L]
7.66 8.45 21.0 656 260

- Culture medium different from test medium: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L
- Intervals of water quality measurement: test start (0h) and test end (48h)

OTHER TEST CONDITIONS
- Photoperiod: 16/8 h light/dark cycle
- Light intensity: Diffuse light, light intensity of max. 20 µE x m-2 x s-1

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Immobilisation, 24 h interval

TEST CONCENTRATIONS
- Test concentration: limit concentration (saturated solution, nominal loading 1.00 mg/L)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL100

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL10

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Details on results:

See below

Results with reference substance (positive control):

The percentage immobility for the reference item was determined after 24 h. The EC50-value with 95 % confidence interval (CI) was calculated by sigmoidal dose-response regression. The EC50-value for the most recent of the monthly performed reference tests was:
EC50: 1.56 mg/L (CI 1.53 - 1.58 mg/L).
The EC50-value of the reference item potassium dichromate after 24 h is within the prescribed concentration range of 0.6 - 2.4 mg/L of quality criteria according to AQS P 9/2 (02/2000) for daphnids clone 5 cultured in Elendt M4 medium. The EC50-value of the reference item is also within therecommended range of 0.6 - 2.1 mg/L according to OECD-Guideline 202.

The percentage immobility, determined in the saturated solution with a nominal loading of 1.00 mg/Lof the test item and the control after 24 and 48 h under static conditions, is presented in the table below. There was no effect observed at the saturated solution and the control.

 

Immobilisation Rates of the definitive Test after 24 and 48 hours of Exposure

(n = 20, divided into 4 replicates with 5 daphnids each)

Nominal loading of the test item   [mg/L]	IMMOBILISATION [%]
	24 h					48 h
	Replicates					Replicates
	1	2	3	4	MV	1	2	3	4	MV
1.00 (Saturated solution)	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

MV   = mean value

All replicates of the saturated solution of the test item and the control were colourless and clear throughout the exposure period.

 

Validity criteria fulfilled:

yes

Conclusions:

At the saturated solution with a nominal loading of 1.00 mg/L of the test item no effects were observed on Daphnia magna.

Executive summary:

In the acute immobilisation test with Daphnia magna (STRAUS), the effects of the saturated solution* with a nominal loading of 1.00 mg/Lof the test item were determined according to OECD 202 (2004).The limit test was conducted under static conditions over a period of 48 hours from 2014-08-25 to 2014-08-29, with the definitive exposure phase from2014-08-27 to 2014-08-29.

The test item is an orange powder and sparingly soluble in water (< 0.02 mg/L at 20 °C). Therefore, a saturated solution was prepared by stirring with approximately 1100 rpm for 48 h at room temperature followed by centrifugation for 10 minutes at 18533 g at 20 °C to remove undissolved test item to achieve the saturated solution.Twenty daphnids were exposed to the saturated solution and the control.

No analytical monitoring was performed during the test period in agreement with the sponsor, because the test item is insoluble in water and organic solvents, which are compatible for liquid chromatography. Due to this fact, an analytical standard method with a sufficient sensitivity could not be established. Exposures are expressed in terms of the original concentration of the test item in water at the start of the mixing period (loading rate). The EL-values are presented in the table below.

Water quality parameters (i.e. pH-value and dissolved oxygen concentration), measured at the start (0 h) and at the end of the exposure (48 h), were within the acceptable limits. The validity criteria of the test guidelines were fulfilled.

 

At the saturated solution* with a nominal loading of 1.00 mg/L of the test item, no effects were observed on Daphnia magna.

 

  EL₁₀-, EL₅₀-EL₁₀₀-Values, NOEL and LOEL

   (based on the nominal loading levels of the test item)

Endpoints	Test duration [h]
		Nominal loading level of the test item [mg/L]
EL10 / 50 / 100	24	> 1.00
	48	> 1.00
NOEL	48	1.00
LOEL	48	> 1.00

*)  Saturated solution: The maximum dissolved concentration of the test item that can be achieved under the test conditions in the test medium,

acc. to OECD Series, No. 23 (2000).

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Please refer to attached read across justification document (Chapter 13).

Reason / purpose for cross-reference:

read-across source

Duration:

48 h

Dose descriptor:

NOELR

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

LOELR

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL100

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Duration:

48 h

Dose descriptor:

EL10

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Validity criteria fulfilled:

yes

Conclusions:

At the saturated solution with a nominal loading of 1.00 mg/L of the test item no effects were observed on Daphnia magna.

Description of key information

The saturated solution of the test item was found not to cause effects to Daphnia after 48 hours at a nominal concentration of 1.00 mg/L.