Butyl decanoate

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:

19 - 21 Sep 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of certificate: 14.03.2017 (The Department of Health of the Government of the United Kingdom)

Test material

Test material information

Constituent 1

Reference substance name:

Butyl decanoate

EC Number:

250-280-5

EC Name:

Butyl decanoate

Cas Number:

30673-36-0

Molecular formula:

C14H28O2

IUPAC Name:

butyl decanoate

Test material form:

liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all concentrations, taken at start and end of the 48 hour exposure period.
- Sampling method: Samples were taken from remaining test media after filling test vessels for 0 hours and pooled replicate flasks for 48 hours.

Test solutions

Vehicle:

yes

Remarks:

Dichloromethane

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Stock solutions were prepared separately by adding the appropriate amount of test substance to solvent (DCM). The total volume of the solvent in the stock solution was 10 mL. The test concentrations were prepared by adding 5 µL of the corresponding stock solution to a total volume of 50 mL of media water.
- Chemical name of vehicle : Methanol for the range finding test and Dichloromethane (DCM) for the definitive test.
- Volume of solvent in solvent control: 5 µL

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: From cultures maintained at Chemex Environmental International Ltd since July 2014 and originally sourced from a clone of genotype 5
- Age of parental stock: ≤ 24 hours
- Feeding during test: no

CULTURE CONDITIONS
- Cultured under static conditions
- Temperature: 20 ± 2°C
- Dissolved oxygen: >60% (or 3 mg/L) ASV
- Photoperiod: 16 hours light and 8 hours dark
- Acclimation conditions: same as in test
- Type of food: suspension of Chlorella vulgaris.
- Feeding frequency: Each working day

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

20.7 - 21.9 °C

pH:

7.30 - 7.63

Dissolved oxygen:

6.04 - 7.16 mg/L

Nominal and measured concentrations:

Nominal test concentrations:control, solvent control, 0.134, 0.429, 1.370, 4.380, 14.0 and 45 mg/L
Mean measured concentrations: control, solvent control, 0.059, 0.073, 0.064, 0.085, 0.169 and 0.179 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Plastic pots (nominal volume 50 mL), covered with a perspex sheet
- Fill volume: 50 mL
- 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 Daphnia water

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 hours dark cycle

EFFECT PARAMETERS MEASURED : The number of immobilised Daphnia was recorded after 24 and 48-hour exposure.

VEHICLE CONTROL PERFORMED: yes

TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: solvent control (methanol), 0 (control), 0.1, 1.0, 10, 50 mg/L
- Results used to determine the conditions for the definitive study: EC50 (72 h): 10 - 50 mg/L (nominal)

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

4.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: (3.5 - 6.4 mg/L; 95% confidence limits)

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.09 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: (0.08 - 0.14 mg/L; 95% confidence limits)

Details on results:

- Mortality of control or solvent control: No
- Other adverse effects control or solvent control: No

Results with reference substance (positive control):

EC50 (24 h): 1.4 mg/L of potassium dichromate (obtained in a separate GLP study conducted from 18 to 20 January 2017)

Reported statistics and error estimates:

ToxCalc™ Version 5.0 “Comprehensive Toxicity Data Analysis and Database Software”, copyright 1994-1996.

Any other information on results incl. tables

Table 1: Cumulative immobilisation

Nominal Concentration mg/L	Mean measured concentrations mg/L	Number immobilised		% immobilisation
		24 hours	48 hours	24 hours	48 hours
0 (Control)	0 (Control)	0	0	0	0
Solvent control (DCM)	Solvent control (DCM)	0	0	0	0
0.134	0.059	0	0	0	0
0.429	0.073	0	0	0	0
1.370	0.064	0	0	0	0
4.380	0.085	6	10	30	50
14	0.179	10	19	50	95
45	0.169	14	20	70	100

Table 2 Biological observations

Nominal Concentration mg/L	Recorded observations
	24 hours	48 hours
0 (Control)	20NS	20NS
Solvent control (DCM)	20NS	20NS
0.134	13NS5Ms2TM	16NS2Ms2TM
0.429	16NS1Ms3TM	9NS9Ms1TMLI1TM
1.370	4NS2Ms14TM	4NS7Ms9TM
4.380	4TM4TMD2DMs4TMDMs	2TM3TMMs1Ms2TMDMs1MsLI1TMLIMs
14	10TMDMs	1MsD
45	6TMDMs	-

Key to comments
S	Sedimentation	Ms	Movement Slower
D	Debris attached to Daphnia	TM	Trapped in Meniscus (mobile)
LI	Lighter Colouration	TI	Trapped in Meniscus (immobile)
NS	No Signs of Abnormality	SM	Daphnia Smaller
-	All Daphnia immobilised

Table 3: Validity criteria for OECD 202.

Criterion from the guideline	Outcome	Validity criterion fulfilled
In the control, including the control containing the solubilising agent, not more than 10% of the daphnids should have been immobilized.	0%	yes
The dissolved oxygen concentration at the end of the test should be ≥ 3 mg/L in control and test vessels.	>6 mg/L	yes

 

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

see Table 3 at "Any other information on results incl. tables"