p-methoxybenzyl acetate

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:

2000-04-12 to 2000-04-14

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1984

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The nominal stock solution of 100 mg/L was prepared with dilution water one day prior to application and filtered (45p) before use.
- Stock solution: 100 mg/L, prepared with dilution water one day prior to application and filtered (45 µm) before use.
- Controls: Dilution water without test item tested under the same conditions as the test groups.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain: Straus (Clone 5)
- Age at study initiation: Less than 24 h old
- Method of breeding: In 2-3 L glass vessels with approximatively 1.8 L culture medium, by 21 °C (temperatures of 20-25 °C were tolerated), in an incubator, 16 h illumination, illumination strength 1.5-5.0 µmol* mE-2 * sE-1 ( 100 - 200 lx).
- Food type: mix of Scenedesmus subspicatus and Chlorella vulgaris, with an algae cell density of > 10E+06 cells/mL.
- Frequency: 5 x weekly ad libitum

ACCLIMATION
- Acclimation period: 2 h in dilution water

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

238 mg/L CaCO3 (dilution water)

Test temperature:

21 ± 1 °C constant

pH:

Control: 7.59; 48 h: 7.53-7.63
10 mg/L: 7.38; 48 h: 7.42-7.55
18 mg/L: 7.49; 48 h: 7.39-7.52
32 mg/L: 7.51; 48 h: 7.45-7.53
58 mg/L: 7.39; 48 h: 7.42-7.51
100 mg/L: 7.4; 48 h: 7.35-7.49

Dissolved oxygen:

Control: 8.61 mg/L ; 48 h: 7.48-7.61
10 mg/L: 8.53; 48 h: 7.31-7.51
18 mg/L: 8.38; 48 h: 6.92-7.49
32 mg/L: 8.45; 48 h: 7.21-7.63
58 mg/L: 8.27; 48 h: 6.85-7.61
100 mg/L: 8.51; 48 h: 7.36-7.46

Salinity:

not applicable

Conductivity:

666 µS/cm (dilution water)

Nominal and measured concentrations:

10 - 18 - 32 - 58 - 100 mg test item/L (nominal)
/-/-22.4-38.5-69.9 mg C/L (measured DOC at 0 h)

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (5 cm ID x 8 cm H), 50 mL
- Type: open
- Fill volume: 20 mL
- Application: Once within 48 h
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: According to EEC 92/69 L383A C.2.
- Total organic carbon: 100 mg/L: 66.6 mg/L, 58 mg/L: 38.6 mg/L, 32 mg/L: 21.3 mg/L

OTHER TEST CONDITIONS
- Photoperiod: 16/8 h light/dark cycle
- Light intensity: Diffuse light, illumination range 1.5-5.0 µmol* mE-2 * sE-1

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Range finding study
- Test concentrations: 1 -100 mg/L (nominal concentration), set up in a geometric series with a factor of 10 (NON-GLP-state).
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate p.a. (0.58 - 1.0 - 1.8 - 3.2 - 5.8 mg/L)

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

31 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 28 - 34 mg/L

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: See following table
- Observations on body length and weight: No body weight and length was determined.
- Other biological observations: No.
- Mortality of control: No.
- Adverse effects control: No immobilisation was observed for control animals.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No. All tested concentration Ievels were clearly dissolved throughout exposure.
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid: yes
- EC50: 2.4 (Cl 2.2-2.5)

Percentage of daphnids incapable of swimming after 24 and 48 h of exposure (n 20)

Test substance	Immobilisation [%]
nominal concentration [mg/L]	24 h					48 h
	Replicates					Replicates
	1	2	3	4	MV	1	2	3	4	MV
100	80	80	60	80	75	100	100	100	100	100
58	40	60	80	40	55	100	80	100	100	95
32	60	40	40	40	45	60	60	60	60	60
18	0	20	0	0	5	0	20	0	0	2
10	0	0	0	0	0	0	0	0	0	0
Control	0	0	0	0	0	0	0	0	0	0

MV = Mean value

Validity criteria fulfilled:

yes

Conclusions:

An EC50 of 31 mg/L (48 h) was determined with a short-term toxicity test in daphnia.

Executive summary:

In the acute immobilisation test with Daphnia magna (STRAUS), the effects of the test item were determined according to OECD 202. The study was conducted under static conditions over a period of 48 h with the following concentrations: 10 - 18 - 32 - 58 - 100 mg/L (nominal). Twenty Daphnids were exposed to each concentration level and the control. The EC10 and EC50 values were determined by probit analysis and the EC100 value was deduced directly from the dose-response-relationship. The EC10, EC50 and EC100 values were derived for 24 and 48 h. The EC50 of 52 mg/L (24 h) and 31 mg/L (48 h) was determined for daphnia based on nominal concentration.

Description of key information

An EC50 of 31 mg/L (48 h) was determined with a short-term toxicity test in daphnia.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

31 mg/L

Additional information

In an acute immobilisation test with Daphnia magna (STRAUS), the effects of the test item were determined according to OECD 202. The study was conducted under static conditions over a period of 48 h with the following concentrations: 10 - 18 - 32 - 58 - 100 mg/L (nominal). Twenty Daphnids were exposed to each concentration level and the control. The EC10 and EC50 values were determined by probit analysis and the EC100 value was deduced directly from the dose-response-relationship. The EC10, EC50 and EC100 values were derived for 24 and 48 h. The EC50 of 52 mg/L (24 h) and 31 mg/L (48 h) was determined for daphnia based on nominal concentration.