(1-methylethylidene)bis(4,1-phenyleneoxy-3,1-propanediyl) bismethacrylate

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:

09 - 12 Jun 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study under GLP, analytical confirmation of exposure, unstable test substance concentration

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Procrylate

IUPAC Name:

Procrylate

Details on test material:

- Name of test material (as cited in study report): MTDID 9115
- Substance type: pure active substance
- Physical state: clear colorless to yellowish liquid
- Analytical purity: 96%
- Expiration date of the lot/batch: 24 Nov 2015
- Storage condition of test material: At room temperature

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: All test concentrations and controls, at t = 0hr and 48 hrs
- Sampling method: Duplicate 1-mL samples were taken from each test concentration. At the beginning of the test, samples were taken directly from the freshly prepared bulk test solutions. At the end of the exposure period, replicates were pooled at each concentration before sampling.
- Sample storage conditions before analysis: in freezer (≤-15 °C)

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Test substance at 100 mg/L in test medium was stirred for two days with a magnetic stirrer. The resulting emulsion was left to settle overnight (~17 hours). Subsequently, the clear and colourless Water Soluble Fraction (WSF) was collected and used as the limit test concentration.
- Controls:Blank test medium
- Evidence of undissolved material: Test solution was clear and colorless

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Straus, 1820
- Source: In-house laboratory culture with known history (at least third generation, obtained by acyclical parthenogenesis under specified breeding conditions).
- Age at study initiation (mean and range, SD): < 24 hours, from parental daphnids of more than two weeks old
- Method of breeding: By acyclical parthenogenesis. Each batch started with newborn daphnids, i.e. less than 3 days old, by placing about 250 organisms into 5 L of M7 medium (based on modified ISO medium, see Test Conditions) in an all-glass culture vessel. Cultures maintained for a maximum age of 4 weeks. After 7 days of cultivation half of the M7 medium was renewed twice per week. Cultures were maintained at 18 - 22 °C and prior to test were fed daily with a suspension of freshwater algae. Stock, 2nd to 5th brood, showed 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.
- Feeding during test: No

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg CaCO3/L

Test temperature:

20.3 - 21.0 °C

pH:

8.0-8.2

Dissolved oxygen:

9.1 - 9.3 mg/L

Nominal and measured concentrations:

Nominal:Control (0 mg/L), 100 mg/L
Measured:

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL all-glass vessel, 80 mL fill volume
- Aeration: No
- 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: Water used to prepare media was tap water purified by reverse-osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands)
- Culture medium different from test medium: Yes.
Test medium: Adjusted ISO medium.
CaCl2∙2H2O 211.5 mg/l
MgSO4∙7H2O 88.8 mg/l
NaHCO3 46.7 mg/l
KCl 4.2 mg/l
Culture medium: M7; M7 as used in this laboratory is prepared using a slightly modified ISO medium supplemented with macronutrients, micronutrients and vitamins as per standard M7 medium (OECD 202).

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16h light, 8h dark
- pH and dissolved oxygen were measured at the beginning and ending of the test, temperature was measured continuously in a temperature control vessel

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : At 24h and 48h, immobility (including mortality) was measured.

TEST CONCENTRATIONS
- Range finding study: yes, done in parallel to limit test
- Test concentrations: Control, 1.0% and 10% dilutions of WSF
- Results used to determine the conditions for the definitive study: no

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 2 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No immobilization observed in controls or exposed vessels

Details on results:

- Other biological observations: One control organism trapped at medium surface, but regained mobility when reimmersed.
- Mortality of control: No
- Other adverse effects control: No
- Abnormal responses: No
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: Substance was sparingly soluble in test medium, but water soluble fractions were clear and colorless
- Effect concentrations exceeding solubility of substance in test medium: Yes

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50: 0.32 mg/L. Historical range for the reference substance at the contract lab lies between 0.3 and 1.0 mg/L
- Other: Reference substance toxicity assay conducted 92 days prior to test substance.

Reported statistics and error estimates:

No statistics are available because no immobilization occurred at any concentration.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

<10% immobilization in controls, DO >3mg/L in all test vessels

Conclusions:

The EC50 of Procrylat to D. magna is > 2.0 mg/L (no immobilization at this concentration).

Executive summary:

Toxicity of Procrylat to D. magna was assessed in a limit test conducted according to OECD 202. The test substance was not soluble at the limit of 100 mg/L. Four replicates were prepared of negative controls and at 100 mg/L nominal. Mean (geometric) procrylate concentration was 2.0 mg/L. No immobilization was observed observed after 48 hours in negative controls or exposed organisms. The 48-hour EC50 of procrylate is >2.0 mg/L.

The test was conducted according to an internationally accepted guideline and was GLP compliant. Test substance concentrations were analytically confirmed, but decreased throughout the test. This test is considered reliable with restrictions. It is suitable for Risk Assessment, Classification & Labeling, and PBT Analysis.