[(2,4-dibromophenoxy)methyl]oxirane

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:

May - October 2017

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)

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: CG272
- Expiration date of the lot/batch: 11. July 2018
- Purity test date: not stated

RADIOLABELLING INFORMATION (if applicable)
not applicable

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Stability under test conditions: assumed stable
- Solubility and stability of the test substance in the solvent/vehicle: solubility 68.3 mg/L in water, assumed stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: assumed not reactive

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
none

Analytical monitoring:

yes

Details on sampling:

not stated

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
The solubility in dilution water was tested before the start of the test. As solubility lies below
100 mg/L, the water-accommodated fraction was prepared for the test. This was done
by weighing the nominal load of 100 mg/L (real load 101.9 mg/L) adding the corresponding
amount of dilution water and shaking vigorously for 24 hours. The resulting solution was
filtrated through 0.45 μm PTFE filters.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species Daphnia magna
Variety STRAUS
Strain Berlin
Sex female
Age between 0 and 24 hours
Origin Umweltbundesamt Berlin
In-house breeding since 27. September 2007
Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for
the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical.
The husbandry is performed similar to the method described in the OECD guideline, following
SOP 115 002 01 („Zucht und Hälterung von Daphnia magna STRAUS“), version 12
from 02. Feb. 2015.
Vessels preserving glasses, nominal volume 2 L
Medium M4-Medium (recipe of ELENDT)
Food unicellular green algae (Desmodesmus subspicatus)
Medium renewal twice a week
Photo period 16/8 hours, using neon tubes
Temperature 20.0  2.0 °C

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

none

Hardness:

250

Test temperature:

20.4 – 22.4 °C

pH:

7.7 - 8.0

Dissolved oxygen:

8.5 - 9.0 mg/L

Salinity:

not stated

Conductivity:

not stated

Nominal and measured concentrations:

At the start of the test the measured concentration of the test item was between 60 % and
66 % of the nominal concentration and after 48 hours the measured concentration was
between 53 % and 55% of the nominal concentration.

Details on test conditions:

Medium renewal none
Test vessels glass beakers, nominal volume 100 mL, tall shape
Replicates (Treatments) 4 vessels, each containing 50 ± 5 mL test solution and 5
Daphnia
Replicates (Blank control) 4 vessels, each containing 50 ± 5 mL dilution water and 5
Daphnia

Reference substance (positive control):

yes

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

6.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

2.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

1.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

2.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

VALIDITY
 Immobilisation in the blank controls was 0 %.
 The concentration of dissolved oxygen at the end of the test must be at least 3 mg/L.
The lowest concentration of dissolved oxygen at the end of the test was 8.5 mg/L.
 The pH-value in the test solutions should not vary by more than 1.5 units during the
test.
The highest variation was 0.3 units.

Results with reference substance (positive control):

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a
current reference study. The 24h-EC50i value was determined as 1.6 mg/L.

Reported statistics and error estimates:

The estimation of the biological results was accomplished using the software ToxRat®
Professional, version 3.1. The details of calculation are stated in attached documents: Statistical calculation
using ToxRat® Professional 3.2.1

Validity criteria fulfilled:

yes

Conclusions:

he following results were determined for the test item DENACOL EX-147 (species:
Daphnia magna).
48h-NOEC = 1.3 mg/L
48h-LOEC = 2.6 mg/L
24h-EC50 = 6.7 mg/L
48h-EC50 = 2.5 mg/L

Executive summary:

One valid experiment was performed.

The study was performed using 6 concentrations ranging from 1 to 46 mg/L nominal concentration.

For each test concentration, 20 Daphnia were exposed to the test item for 48

hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

Four concentrations showed toxicity between 65 and 100% immobilisation after 48 hours.

None of the animals were immobilised in the blank control.

Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a

current reference study to assure that the test conditions are reliable.

At the beginning and at the end of the test, the content of the test item in the test solutions

was determined using GC/FID-determination. At the start of the test the measured concentration

of the test item was between 60 % and 66% of the nominal concentration and after

48 hours the measured concentration was between 53 % and 55% of the nominal concentration.

Therefore, the determination of the biological results was based on the geometric

mean of measured concentrations.

The following results were determined for the test item DENACOL EX-147 (species:

Daphnia magna).

48h-NOEC = 1.3 mg/L

48h-LOEC = 2.6 mg/L

24h-EC50 = 6.7 mg/L

48h-EC50 = 2.5 mg/L

Description of key information

one valid Guideline Study available on toxicity towards Daphnia Magna

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.5 mg/L