4-(2-acryloyloxy-ethoxy) benzophenone

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:

25th-27th November, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

4-(2-acryloyloxy-ethoxy) benzophenone

EC Number:

836-681-3

Cas Number:

22421-66-5

Molecular formula:

C18H16O4

IUPAC Name:

4-(2-acryloyloxy-ethoxy) benzophenone

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: SGS Belgium NV, Lot# 30029
- Expiration date of the lot/batch: 3rd May 2020
- Purity test date: 3rd May 2019
- Purtiy: 92.5 w%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature in a dark, ventialted cabinet in the original container.
- Stability under storage conditions: Stable
- Stability under test conditions: Stable

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Nominal: 0.63, 1.3, 2.5, 5.0, 10 mg/L
- Sampling method: Water samples were taken from the approximate midpoint of each test concentration vessel upon initial exposure (0 hour) and at the termination of the experiment (48 hour). During initial exposure, samples were taken from the intermediate vessels before division into replicates. At termination, replicate solutions from each respective concentration were composited before sampling. A sample of the stock solutions used in the preparation of exposure solutions was also sampled. Test samples (10 mL) were taken from the exposure solutions and directly transferred to disposable glass vials containing 10 mL acetonitrile (to a final composition of 50/50 acetonitrile/ fortified laboratory well water, v/v). Samples were then diluted into the calibrated standard range with 50/50 acetonitrile/fortified laboratory well (v/v) prior to analysis. Three quality control samples, prepared in diluent water at test substance concentrations similar to the treatment level range, were also run during each sampling interval and analyzed with the study samples.
- Sample storage conditions before analysis: Analysis was run immediately after sampling, or the acetonitrile-amended samples were stored until analysis could be performed. If not immediately analyzed, stability of the test substance in dilution water was determined. Stability of test substance during storage was verified by analysis of the QC samples. In addition, sub-samples of the test solutions were collected at each sampling interval and stored frozen as archive samples.

Test solutions

Vehicle:

yes

Remarks:

Acetone

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Primary and secondary stock solutions were made in acetone. An aliquot of a secondary stock was added to each exposure solution. Exposure solutions were mixed slowly overnight using a magnetic stir plate and teflon coated stirbar. After overnight mixing, a 20 minute settling period was allowed and exposure solutions were clear and colorless with no visible undissolved test material. The test solution was then diluted to the correct nominal concentrations.
- Controls: Test medium without test substance and test medium with acetone
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Acetone
- Concentration of vehicle in test medium (stock solution and final test solution(s) or suspension(s) including control(s)): 0.100 mL/L of acetone
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): The primary and secondary stock solutions were clear and yellow in color with no visible undissolved test substance. Undissolved test material was observed on the surface of the 2.5, 5.0, and 10mg/L concentrations. After mixing overnight and a 20 minute settling period, all exposure solutions were clear and colorless with no visible undissolved test substance.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Age at study initiation: <24 hours.
- Source: Smithers culture
- Feeding during test : No
- Presence of ephippia: none
- Culture conditions: Adult daphnids were cultured in fortified laboratory well water, pH 7.6 - 8.5, hardness 180 mg CaCO3/L, alkalinity 82 mg CaCO3/L. During the test period, the water temperatures were 19 - 21°C and photoperiod was 16h light, 8 h dark (670 - 1100 lux). Daphnids in the cultures were fed once daily a suspension of green algae (Ankistrodesmus falcatus, 4X10^7 cell/mL) and YCT suspension (yeast, cereal leaves and flaked fish food).
​​​​​​​
- Common name: Water flea
- Age at study initiation: Immature organisms were removed from culture 24 hours prior to test.
- Source: Smithers culture
- Feeding during test : No
- Presence of ephippia: None
- Culture conditions: Adult daphnids were cultured in fortified laboratory well water, pH 7.6-8.5, hardness 180 mg CaCO2/L, alkalinity 82 mg CaCO3/L. During the test period, the water temperatures were 19 - 21°C and photoperiod was 16h light, 8 h dark (670-1100 lux). Daphnids in the cultures were fed once daily a suspension of green algae (Ankistrodesmus falcatus) and YCT suspension (yeast, cereal leaves and flaked fish food).

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

180 CaCO3 mg/L

Test temperature:

19-21°C

pH:

7.8-8.2

Dissolved oxygen:

7.8-8.9 mg/L

Conductivity:

890 uS/cm

Nominal and measured concentrations:

Nominal: 0.63, 1.3, 2.5, 5.0, 10 mg/L
Mean measured: 0.43, 0.93, 1.6, 4.3, 8.9 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 mL glass beaker covered with clear plastic
- Volume of solution: 200 mL
- Aeration: No
- Renewal rate of test solution: None
- 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
- Biomass loading rate: 40 mL/daphnid

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Well water fortified with 192 mg/L NaHCO3, 120 mg/L CaSO4.H2O, 120 mg/L MgSO4, 8.0 KCl
- Total organic carbon: 1.0 mg/L
- Particulate matter: < 1 mg/L
- Representative samples analyzed for pesticides, PCB's and toxic metals were not detected at concentrations that are considered toxic in any of the water samples analyzed.
- Alkalinity: 82 mg CaCO3/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: semi-annually



OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16h light, 8h dark
- Light intensity: 780-900 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobilization (including mortality) at 24 and 48 hours.

VEHICLE CONTROL PERFORMED: Yes

RANGE-FINDING STUDY
- Test concentrations: Solvent control, 0.01, 0.1, 1.0 10 mg/L
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

3.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CI: 3.1 - 4.5mg/L

Details on results:

- Mortality of control: No mortality of the control.
- Behavioral abnormalities: None reported
- Other adverse effects control: None reported
- Immobilisation of control: No immobilization of the control.

Results with reference substance (positive control):

24 hour EC50=1.9 mg/L. Reference test: 4th-5th September 2019 (50 days before definitive test).

Reported statistics and error estimates:

Statistics run: Jonckeere-Terpstra's Step-Down Test and Spearman Kaber analysis within CETIS v1.9 software (Tidepool Scientific Software, McKinleyville, CA).

Any other information on results incl. tables

Table 1. 48-Hour Static Exposure of Daphnids (Daphnia magna) to MTDID 32918- Concentrations Measured in Exposure Solutions

Nominal conc (mg/L)	Measured conc-0 hours	Measured conc-48 hours	Mean	Percent of Nominal
Control	<0.10	<0.10	NA	NA
Solvent Control	<0.10	<0.10	NA	NA
0.63	0.50	0.36	0.43	68
1.3	1.1	0.81	0.93	72
2.5	1.7	1.7	1.6	66
5	4.2	4.2	4.3	85
10	8.2	9.6	8.9	89
QC#1  0.3	0.292 (97.2)	0.351 (117)	­	­
QC#2  2.5	2.41 (96.4)	2.96 (119)	­	­
QC#3  10	9.66 (96.6)	9.83 (98.3)	­	­

NA=Not Applicable

QC=Quality Control. Percent recovered presented in parentheses

LOD (or MDL) was 0.10 mg/L

Table 2. 48-Hour Static Exposure of Daphnids (Daphnia magna) to MTDID 32918- Mean Measured Concentrations Tested and Corresponding Cumulative Percent and Number of Immobilized Organisms

Mean Measured conc (mg/L)	Replicate	Percent Immobilization-24 hours	Percent Immobilization-48 hours
Control	A	0	0
	B	0	0
	C	0	0
	D	0	0
	Mean	0	0
Solvent Control	A	0	0
	B	0	0
	C	0	0
	D	0	0
	Mean	0	0
0.43	A	0	0
	B	0	0
	C	0	0
	D	0	0
	Mean	0	0
0.93	A	0	0
	B	0	0
	C	0	0
	D	0	0
	Mean	0	0
1.6	A	0	0
	B	0	0
	C	0	0
	D	0	0
	Mean	0	0
4.3	A	0	60 (3)
	B	0	60 (3)
	C	20 (1)	60 (3)
	D	40 (2)	60 (3)
	Mean	15	60
8.9	A	100 (5)	100 (5)
	B	100 (5)	100 (5)
	C	100 (5)	100 (5)
	D	100 (5)	100 (5)

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

<10% mortality in controls (0%), Dissolved oxygen concentration was ≥ 3 mg/L during test period (DO=7.8-8.9)

Conclusions:

48 hour EC50 of 3.7 mg/L (OECD 202) in Daphnia magna.

Executive summary:

The 48 hour EC50 of aryloxyacrylate to Daphnia magna was determined according to OECD 202 guidelines. Nominal concentrations of 0.63, 1.3, 2.5, 5.0, 10 mg/L, a control, and a solvent control, were run using 5 animals per vessel, with four replicate per concentration. An EC50 of 3.7 mg/L (mean measured concentration) was determined.

The study was well-documented, followed an international standard method with analytical confirmation of dose and was GLP compliant. The study is considered reliable without restrictions. The results from this study are considered suitable for Risk Assessment, Classification and Labeling, and PBT Analysis