(3E)-dec-3-en-2-one

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:

28 June 2011 to 22 September 2011

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)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: One sample from the freshly prepared stock solution and duplicate samples from the freshly prepared test media of all test concentrations and the control, were taken at the start of the test and at day 1. For the determination of the stability of the test item under the test conditions and of the maintenance of the test item concentrations during the test period, duplicate samples from the aged test media of all test concentrations and the control were collected at the end of the test and at day 1 (after 24 hours of exposure) by pouring together the contents of the test beakers of each treatment.
- Sample storage conditions before analysis: All samples were analysed directly after sampling without prior storage.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Before test start and before the test medium renewal a concentrated stock solution of nominally 100 mg test item/L was prepared by dissolving 30.1 mg test item into 301 mL test water and 30 mg test item into 300 mL of test water by intense stirring for 15 minutes at room temperature. Then, appropriate volumes were mixed with test water to obtain the desired test concentrations.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: 5
- Age at study initiation (mean and range, SD): 6.0 to 22.5 hours
- Method of breeding: The daphnids were bred in the laboratories of IBACON under similar temperature and light conditions as used in the test. The parental daphnids were cultured in the same reconstituted water as used in the test.
- Source: 1st instar Daphnia magna derived from in-house laboratory cultures.
- Feeding during test
The daphnids in the stock culture were fed at least on all working days with green algae (Desmodesmus subspicatus) freshly grown in the laboratories of IBACON.


ACCLIMATION : Was not necessary, since the test was performed in the same medium as the culturing.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

150 mg/L as CaCO3

Test temperature:

20 to 21 °C

pH:

7.8 to 7.9

Dissolved oxygen:

8.2 to 9 mg/L

Nominal and measured concentrations:

nominal: 10.0, 4.55, 2.07, 0.94, 0.43, 0.19 and 0.088 mg/L
measured; geometric mean: 7.90, 3.32, 1.43 and 0.71 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beakers
- Type (delete if not applicable): covered with a lid
- Material, size, headspace, fill volume: 100 mL
- Volume of solution: 60 mL
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): A semi-static test system with a test medium renewal on Day 1 was chosen to keep the concentrations of test item as constant as possible in the test media.
- 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


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4/Reconstituted Water

Main Compounds:
- CaCl2 x 2 H2O: 293.80 mg/L
- MgSO4 x 7 H2O: 123.30 mg/L
- KCl: 5.80 mg/L
- NaHCO3: 64.80 mg/L
- Na2SiO3 x 9 H2O: 10.00 mg/L
- NaNO3: 0.27 mg/L
- KH2PO4: 0.14 mg/L
- K2HPO4: 0.18 mg/L

Trace Elements: Vitamins:
- H3BO3: 2860 µg/L Thiamin HCl: 75.0 µg/L
- MnCl2 x 4 H2O: 361 µg/L Cyanocobalamin (B12): 1.0µg/L
- LiCl: 306 µg/L Biotin (B6): 0.75 µg/L
- RbCl: 71 µg/L
- SrCl2 x 6 H20 152 µg/L
- NaBr: 16 µg/L
- Na2MoO4 x 2 H2O: 63 µg/L
- CuCl2 x 2 H2O: 17 µg/L
- ZnCl2: 13 µg/L
- CoCl2 x 6 H2O: 10 µg/L
- KI: 3.3 µg/L
- Na2SeO3: 2.2 µg/L
- NH4VO3: 0.6 µg/L
- Na2EDTA x 2 H2O: 2.5 mg/L
- FeSO4 x 7 H2O: 1.0 mg/L

- Alkalinity: 0.9 mmol/L
- Conductivity: < 5µS.cm-1
- Culture medium different from test medium: No


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light : 8 h dark
- Light intensity: 900 - 1050 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobility and sublethal effects
The mobility of the daphnids was determined by visual observation after 24 and 48 hours. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker were considered to be immobile (even ifthey could still move their antennae).

RANGE-FINDING STUDY
- Results used to determine the conditions for the definitive study: Yes

Reference substance (positive control):

no

Remarks:

For the evaluation of the quality of the daphnid clone used and the consistency of the experimental conditions, the reference item potassium dichromate is tested at least twice a year to demonstrate satisfactory test conditions.

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1.68 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

1.43 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.71 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: No
- Other biological observations: No remarkable observations, the test media were clear and colourless
- Mortality of control: No immobilisation after 48 h of exposure
- Other adverse effects control: No
- Immobilisation of control: Immobilisation of the test organisms in the control at the end of the test was 0 % and therefore ≤ 10 %.
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: No

Results with reference substance (positive control):

- Results with reference substance valid? Yes
Results of the most recent Test with the Reference Item Potassium dichromate performed in January 2011
- Tested concentrations: 0.13, 0.28, 0.62, 1.4, 3.0 mg/L
- Limit test: No
- Dose-response test: Yes
- 48-h EC50: 0.91 mg/L (95 % CI: 0.42 to 2.32 mg/L)
- 48-h NOEC: 0.62 mg/L

Reported statistics and error estimates:

The 24-hour and 48-hour EC50 and the 95 % confidence limits were calculated by Probit analysis using the geometric mean measured test item concentrations. The software used to perform the statistical analysis was ToxRat Professional, Version 2.10.05, ToxRat® Solutions GmbH.

Table 1. Influence of the test item on the mobility of D. magna

Nominal Concentration	Mean Measured Concentration	No. of Daphnids tested	No. of immobilised Daphnids after		% of immobilised daphnids after
[mg test item/L]	[mg test item/L]		24 hours	48 hours	24 hours	48 hours
Control	Control	20	0	0	0	0
0.088	n.a.*	20	0	0	0	0
0.19	n.d.*	20	0	0	0	0
0.43	n.d.*	20	0	0	0	0
0.94	0.71	20	0	0	0	0
2.07	1.43	20	0	2	0	10
4.55	3.32	20	10	20	50	100
10	7.9	20	20	20	100	100
n.d.: could not be determined n.d.*: values could not be determined since the concentrations were below LOQ n.a.* not analysed, since below sensitivity of the analytical method

Validity Criteria of the study:

- Immobilisation  of  the  test  organisms  in  the  control  at  the  end  of  the  test  was  0  %  and  therefore <= 10 %.  

- Dissolved oxygen concentration in the control and the test item treatments at the end of the  test was >= 8.2 mg/L and therefore >=3 mg/L.

Table 2. Results of the determination of the test item in the test samples

Nominal test item concentration [mg/L]	Age		Test item found [mg/L]^1	Calculated test item [mg/L]^1	Nominal [mg/L]^1	% of nominal^2
	day	[h]
control	0	0	<LOD	n.a.	0.000	n.a.
control	1	24	<LOD	n.a.	0.000	n.a.
control	1	0	<LOD	n.a.	0.000	n.a.
control	2	24	<LOD	n.a.	0.000	n.a.
0.19	0	0	0.319	< LOQ	0.190	n.a.
0.19	0	0	0.330	< LOQ	0.190	n.a.
0.19	1	24	<LOD	n.a.	0.190	n.a.
0.19	1	24	<LOD	n.a.	0.190	n.a.
0.19	1	0	<LOD	n.a.	0.190	n.a.
0.19	1	0	<LOD	n.a.	0.190	n.a.
0.19	2	24	0.589	< LOQ	0.190	n.a.
0.19	2	24	0.589	< LOQ	0.190	n.a.
0.43	0	0	0.504	< LOQ	0.430	n.a.
0.43	0	0	0.466	< LOQ	0.430	n.a.
0.43	1	24	<LOD	n.a.	0.430	n.a.
0.43	1	24	<LOD	n.a.	0.430	n.a.
0.43	1	0	0.406	< LOQ	0.430	n.a.
0.43	1	0	0.412	< LOQ	0.430	n.a.
0.43	2	24	0.652	< LOQ	0.430	n.a.
0.43	2	24	0.706	< LOQ	0.430	n.a.
0.94	0	0	0.955	0.955	0.940	102
0.94	0	0	0.917	0.917	0.940	98
0.94	1	24	0.429	0.429	0.940	46
0.94	1	24	0.417	0.417	0.940	44
0.94	1	0	0.716	0.716	0.940	76
0.94	1	0	0.618	0.618	0.940	66
0.94	2	24	0.817	0.817	0.940	87
0.94	2	24	0.818	0.818	0.940	87

1 Rounded result calculated on the exact raw data 

2 Geometric mean values were calculated from the arithmetic mean values from each sample age 

The samples of nominal 0.940 mg test item/L are slightly below LOQ, but are considered reliable

LOD: Limit of Detection = 0.053 mg test item/L

LOQ: Limit of Quantification = 1mg test item/L

n.a. not applicable

Validity criteria fulfilled:

yes

Conclusions:

The toxic effect of the test item (3E)-dec-3-en-2-one to Daphnia magna was assessed in a semi-static dose-response test according to OECD 202. NOEC and LOEC were determined directly from the raw data. EC50 values refer to the geometric mean measured concentrations of the four highest concentrations tested:
- 48-hour EC50 (Daphnia magna) = 1.68 mg/L (geom. mean of measured concentration)
- 48-hour NOEC (Daphnia magna) = 0.71 mg/L mg/L (geom. mean of measured concentration)
- 48-hour LOEC (Daphnia magna) = 1.43 mg/L (geom. mean of measured concentration)

Executive summary:

The 48-hr acute toxicity of (3E)-dec-3-en-2-one to Daphnia magna was studied under semi-static conditions. Daphnids were exposed to control, and test chemical at nominal concentrations of 0.088, 0.19, 0.43, 0.94, 2.07, 4.55 and

10.0 mg/L for 48 hr.  The geometric mean of measured concentrations could only be determined analytically for four highest concentrations resulting in the following results: < LOQ, < LOQ, < LOQ, 0.71, 1.43, 3.32, 7.90 mg/L. LOQ of the method was 1 mg test item/L. As the measured concentrations were not within the range of 80 % of the nominal concentrations, all results are presented based on measured concentrations.

Immobilisation and sublethal effects were observed daily. 

The 48 – hour EC50 was 1.68 mg/L (measured, geometric mean).

The 48 – hour NOEC based on mortality/immobilization was 0.71 mg/L (measured, geometric mean). 

 

Based on the results of this study, (3E)-dec-3-en-2-one would be classified regarding the aquatic hazard as chronic category 2 to D. magna in accordance with the Regulation (EC) No 1272/2008. The substance has not to be categorized as acute toxic to the aquatic environment.

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

 

Test Organism Age (e.g. 1st instar): 6.0 to 22.5 hours

Test Type: Semi Static

 

- 48 hr EC50 (measured): 1.68 mg/L (95%-C.I.: n.d.);

- 48 hr LOEC (measured): 1.43 mg/L

- 48 hr NOEC (measured): 0.71 mg/L

Endpoint(s) Effected: Immobility/Mortality

Description of key information

The toxic effect of the test item (3E)-dec-3-en-2-one to Daphnia magna was assessed in a semi-static dose-response test according to OECD 202. NOEC and LOEC were determined directly from the raw data. EC50 values refer to the geometric mean measured concentrations of the four highest concentrations tested.

The following effect levels were determinded:

- 48 hr EC50 (measured): 1.68 mg/L (95%-C.I.: n.d.);

- 48 hr NOEC (D. magna) = 0.94 mg/L (measured 0.71 mg/L)

- 48 hr LOEC (Daphnia magna) = 2.07 mg/L (measured 1.43 mg/L)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.68 mg/L