Ethyl salicylate

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 2001-02-15 to 2001-02-17

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:

April 04, 1984

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

December 1992

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 200, 100, 50, 25, 12.5 and control
- The test item was analytically verified via DOC analysis according to DIN 38409 part 3. DOC was measured in all concentration levels and control at test start (Oh, fresh media).
- Sample storage conditions before analysis: Refrigerated at 7°C, protected from moisture.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Dispersion treatment: 24 h an a magnetic stirrer. Stock solution: 200 mg/L
- Test concentration:
Test dilutions: 1:16, 1:8, 1:4, 1:2, 1:1.
Real test concentrations: 9.2 - 19 - 40 - 84 - 165 mg/L
- 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 system: Daphnia magna STRAUS (Clone 5)
- Reason for the selection of the test system: Daphnia magna STRAUS belongs, in accordance with the study guideline, to the suitable Daphnia types and are bred in the test facility.
- Culture: 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.m-2.s-1.
- Culture medium: Elendt M4, according to Elendt (1990), modified to a total hardness of 160 to 180 mg CaCO3/L.
- Culture feeding: 5 x weekly ad libitum with a mix of Scenedesmus subspicatus and Chlorella vulgaris, with an algae cell density of > 1E+06 cells/mL.
- Age of the daphnids at the start of the exposure: Less than 24 hours old
- Acclimatization: 2 h in dilution water.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

260 mg/L as CaCO3

Test temperature:

21 ± 1°C

pH:

At the start: 7.61-7.66
At the end: 7.36-7.45

Dissolved oxygen:

At the start: 8.42-8.68 mg/L
At the end: 8.34-8.59 mg/L

Conductivity:

630 μS/cm

Nominal and measured concentrations:

Nominal: 12.5, 25, 50, 100, 200 mg/L
Measured: 9.2 - 19 - 40 - 84 - 165 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers (5 cm ID x 8 cm H), 50 mL
- Test volume: 20 mL
- 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 (Annex)
- Intervals of water quality measurement: Dilution water: 0 hours; Test media: 0 hours and 48 hours

OTHER TEST CONDITIONS
- Photoperiod: 16/8 hours light/dark cycle
- Light intensity: Diffuse light, illumination range 1.5-5.0 μmol.m-2.s-1.

EFFECT PARAMETERS MEASURED: The percentage immobility was determined in all test and control groups after 24 h and 48 h.

RANGE-FINDING STUDY
- Test concentrations: 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: The percentage immobility was determined in all test item dilutions of the stock solution (100 mg/L) and control groups after 24 and 48 hours of exposure under static conditions. After 48 h of exposure the total rate of immobilisation of daphnia was 100 % at the undiluted solution. No biologically significant effect (<=10 %) was seen at the dilution 1:10.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

25 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

28 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

40 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were determined to be within the acceptable limits.
The validity criteria of the test guideline were fulfilled.

Results with reference substance (positive control):

The percentage of immobility for the reference item potassium dichromate was determined after 24 hours.
EC50: 2.4 mg/L
95% confidence limits: 2.2 - 2.6 mg/L
The EC50 value of reference item potassium dichromate after 24 h is within the prescribed concentration range of 1.0 - 2.5 mg/L of quality criteria according to AQS: DIN Guideline 38412 L 30.

Percentage of Daphnids immobilized after 24h and 48h exposure:

Real concentration (mg/L)	% immobilization
	24h	48h
165	100	100
84.000	90	100
40.00	10	100
19.0	0	0
9	5	5
Control	0	0

DOC - Analysis of New Media (0 h):

Nominal test concentration [mg/L]	ThTOC [mg/L]	DOC [mg/L]		Real concentration [mg/L]
		measured	corrected*
200	130	107.76	107.43	165
100	65	54.68	54.35	84
50	32.5	26.52	26.19	40
25	16.3	12.94	12.61	19
12.5	8.1	6.33	6.00	9.2
Control	-	0.33	-	-

*calculated related to ThTOC of 0.65 mgC/mg

EC10-, EC50- (with confidence interval), EC100- values:

	Test duration [hours]	Concentration [mg/L]	Confidence interval p = 95%
EC10	24	40	-
	48	25	-
EC50	24	58	52-64
	48	28	27-29
EC100	24	165	-
	48	40	-

Validity criteria fulfilled:

yes

Conclusions:

The test item was found to be toxic to Daphnia with an 48 hour-EC50 for Daphnia magna of 28 mg/L.

Executive summary:

The acute immobilisation (EC50) of the test item to Daphnia magna (STRAUS) was determined according to OECD Guideline 202 / EEC Directive 92/69/EEC Method C.2.

The study was conducted under static conditions over a duration of 48 hours. 20 test organisms were exposed to each test concentration and control. The test item dilutions were clearly dissolved after filtration of the saturated solution in all tested concentration levels throughout exposure. The real test concentrations were calculated based on DOC-analysis: 9.2 - 19 - 40 - 84 - 165 mg/L.

The EC10 and EC50 values were calculated by probit analysis in the tested concentration range.

A reference test is carried out once per month with potassium dichromate as reference item and the reference toxicity determined. The EC50 -value of the reference item at 2.4 mg/L after 24 h was within the prescribed concentration range of 1.0 to 2.5 mg/L according to AQS, DIN Guideline 38412 L 30.

Water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were determined to be within the acceptable limits.

The validity criteria of the test guideline were fulfilled.

The 48 hour-EC50 for Daphnia magna was 28 mg/L (95% confidence limits: 27-29 mg/L).

.

Description of key information

EC50 (48 h) = 28 mg/L (measured, Daphnia magna, OECD 202.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

28 mg/L

Additional information

The acute immobilisation (EC50) of the test item to Daphnia magna (STRAUS) was determined according to OECD Guideline 202 / EEC Directive 92/69/EEC Method C.2.

The study was conducted under static conditions over a duration of 48 hours. 20 test organisms were exposed to each test concentration and control. The test item dilutions were clearly dissolved after filtration of the saturated solution in all tested concentration levels throughout exposure. The real test concentrations were calculated based on DOC-analysis: 9.2 - 19 - 40 - 84 - 165 mg/L.

The EC10 and EC50 values were calculated by probit analysis in the tested concentration range.

A reference test is carried out once per month with potassium dichromate as reference item and the reference toxicity determined. The EC50 -value of the reference item at 2.4 mg/L after 24 h was within the prescribed concentration range of 1.0 to 2.5 mg/L according to AQS, DIN Guideline 38412 L 30.

Water quality parameters of pH-value and dissolved oxygen concentration measured at 0 and 48 h were determined to be within the acceptable limits.

The validity criteria of the test guideline were fulfilled.

The 48 hour-EC50 for Daphnia magna was 28 mg/L (95% confidence limits: 27-29 mg/L).