2-[(2-methyl-1-oxoallyl)oxy]ethyl hydrogen 3-chloro-2-hydroxypropylphthalate

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:

from 2018-08-06 to 2018-09-10

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:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Version / remarks:

2016

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Remarks:

HPLC method with UV detection

Details on sampling:

- Concentrations: 100 mg/L (limit test)
- Sampling method: For determination of the test item concentrations, four replicate samples (5 mL per replicate) were taken from the test solution (100 mg/L) and from the control at the start and at the end of the test.
- Sample storage conditions before analysis: room temperature

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test solution used in the test was prepared by mechanical dispersion without using of any solubilising agent. An amount of 0.03 g test item was dissolved in 300 mL dilution water (ISO Medium) to obtain the nominal concentration of 100 mg/L. This solution was ultrasonicated for approx. 10 min and then shaken overnight (~300 rpm). To separate possible undissolved material the test solution was filtrated through a 0.45 μm membrane filter before introducing test animals.
- Controls: Untreated control ran parallel in the test.
- Evidence of undissolved material: No

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus)
- Source: Laboratory of Hydrobiology (Central Agricultural Office, Directorate of Plant-, and Soil Protection) 2100 Gödöllő, Kotlán S. u. 3. Hungary
- Breeding conditions: Daphnia were bred in the laboratory. under similar temperature and light conditions as in the test, and in reconstituted water of a similar quality regarding to pH, components of the main ions and total hardness as the test water used in the test. The test animals were fed with centrifuged green alga suspension.
- Age of parental stock: less than 24 hours old
- Feeding during test: none

ACCLIMATION
- Acclimation period: Test animals were bred under similar conditions as that used during the exposure period, therefore additional acclimatisation before the test was not necessary.
- Health during acclimation: No mortality observed

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Remarks on exposure duration:

None

Post exposure observation period:

no

Hardness:

249 mg/L (as CaCO3)

Test temperature:

19.8 - 20.2 °C

pH:

7.89 - 8.31

Dissolved oxygen:

8.29 - 8.72 mg/L

Salinity:

NA

Conductivity:

NA

Nominal and measured concentrations:

Nominal concentration: 100 mg/L (limit concentration)

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- Material, size, headspace, fill volume: glass, approximately 40 mL test medium
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Volume/Organism: 2 mL

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The ISO medium was prepared by adding 25 mL from each of four stock solutions to one litre deionised water proportionally.
Stock solution 1: CaCl2 x 2 H2O 11.76 g/L
Stock solution 2: MgSO4 x 7H2O 4.93 g/L
Stock solution 3: NaHCO3 2.59 g/L
Stock solution 4: KCl 0.23 g/L

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light (artificial illumination) and 8 hours darkness

EFFECT PARAMETERS MEASURED:
The immobility or mortality of the Daphnia was determined by visual observation after 24 and 48 hours of exposure. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker were considered to be immobile.

RANGE-FINDING STUDY
- Results used to determine the conditions for the definitive study: A preliminary test was performed at the nominal concentation of 100 mg/L in order to check the toxicity of the test item on the daphnids up to at least this concentration. In the preliminary test no immobility or any sub-lethal effect was detected in the treated concentration and in the control group during the 48-h exposure period.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

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

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: Not observed
- Observations on body length and weight: No effect observed
- Other biological observations: No effect observed
- Mortality of control: No effect observed
- Other adverse effects control: No effect observed
- Immobilisation of control: No effect observed
- Abnormal responses: No effect observed
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No effect observed
- Effect concentrations exceeding solubility of substance in test medium: No
- The 48-h NOEC was determined to be 100 mg/L and 48-h EC50 value was determined to be > 100 mg/L.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- ECx: The 24 h EC50 of the reference substance was determined to be 1.41 mg/L

Reported statistics and error estimates:

A limit test was performed and toxic effects were not observed. Therefore, statistical analysis was not necessary to evaluate the obtained results.

Validity criteria fulfilled:

yes

Conclusions:

In a key 48-hour static acute toxicity test with Daphnia magna the test item had no toxic effect on Daphnia at 100 mg/L concentration (i.e. limit test concentration). Accordingly, the 48-h EC50 value was determined to be > 100 mg/L.

Executive summary:

The acute Toxicity of the test substance to Daphnia magna was determined in a 48-hour Immobilisation Test (Limit test) according to OECD 202 (2004) under GLP conditions. The purpose of this study was to evaluate the influence of the test item on the mobility respectively survival of Daphnia magna. A limit test was performed in which young Daphnia were exposed to aqueous test media containing the test item for 48 hours at the limit test concentration (i.e. 100 mg/L) plus a control in order to demonstrate that the test item is not toxic to Daphnia magna up to at least the concentration of 100 mg/L. The test item and the control were tested using 20 Daphnia, divided into four groups (glass beaker; test medium approx. 40 mL) of five animals each were exposed to the test item concentration or run as control for 48 hours under static conditions.

The immobility or mortality of the Daphnia was determined by visual observation after 24 and 48 hours of exposure. Concentrations of the test item were determined at the start (0 hours) and the end of exposure (48 hours) using a HPLC-UV method. All validity criteria were met and therefore the study is considered as valid. The measured concentrations of the test item were 88 % of the nominal at the start and 84 % at the end of the test. There was no immobilisation observed in twenty daphnids exposed to each test item treated and control group. Further no abnormal behaviour or appearance of test animals was noted. As the analytically measured concentrations remained within ± 20 % of the nominal concentration, the biological results are based on the nominal test item concentration. In conclusion, the 48-h EC50 value was determined to be > 100 mg/L. The 48-h NOEC was determined to be 100 mg/L. All validity criteria were met.

Description of key information

The short-term toxicity 48-h EC50 value for Daphnia was determined to be > 100 mg/L.

Additional information

In a key 48-hour static acute toxicity test with Daphnia magna according to OECD 202 (2004) the test item had no toxic effect on Daphnia at 100 mg/L concentration (i.e. limit test concentration). Accordingly, the 48-h EC50 value was determined to be > 100 mg/L. All validity criteria were met. The results are based on nominal test item concentration.