(Z)-N-octadec-9-enylhexadecan-1-amide

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 Sep 2019 to 09 Jan 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

2012

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The concentration and stability of the test item in the test preparations were verified by chemical analysis on Days 0, 5, 12 and 19 (fresh media) and on Days 3, 7, 14 and 21 (old media). Duplicate samples were stabilized and taken and stored
frozen for further analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test item solution was prepared by stirring an excess (50 mg/L) of test item in test water using a propeller stirrer at approximately 1500 rpm for 24 hours. After the stirring period any undissolved test item was removed by filtration (0.2 µm Sartorius Sartopore filter, first approximate 1 liter discarded in order to pre-condition the filter) to produce a 100% v/v saturated solution of the test item.
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Age at study initiation (mean and range, SD): not specified
- Stage and instar at study initiation: adult
- Method of breeding: parthenogenesis
- Feeding during test
- Food type: Each daphnid received approximately 5 to 20 μL of an algal suspension (Raphidocelis subcapitata) daily and approximately 5 μL of GM 300 fish food suspension on Days 0 to 3. Feeding was at a level of approximately 0.1 to 0.2 mg carbon/daphnid/day, dependent on the age and size of the animals. Equal amounts of food were given to each daphnid.

ACCLIMATION
- Acclimation period: not specified
- Acclimation conditions (same as test or not): not specified
- Type and amount of food: Each culture was fed daily with a mixture of algal suspension (Raphidocelis subcapitata (formally known as Pseudokirchneriella subcapitata)) and GM300 fish food suspension.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

21 d

Hardness:

see in the "Any other information on results incl. tables" section

Test temperature:

see in the "Any other information on results incl. tables" section

pH:

see in the "Any other information on results incl. tables" section

Dissolved oxygen:

see in the "Any other information on results incl. tables" section

Salinity:

n.a.

Conductivity:

n.a.

Nominal and measured concentrations:

see in the "Any other information on results incl. tables" section

Details on test conditions:

TEST SYSTEM
- Test vessel: glass vessel
- Type (delete if not applicable): closed
- Aeration: no, the diluent water only was aerated prior to use.
- Renewal rate of test solution (frequency): Day 0 to 1, 5 to 6, 12 to 13 and 20 to 21
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): n.a.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted Elendt M4 medium
- Details in the "Any other information on results incl. tables" section

OTHER TEST CONDITIONS
- Photoperiod / Light intensity: 16 hours light (not exceeding 1500 Lux) and 8 hours darkness with 20 minute dawn and dusk transition periods for 21 days.


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Immobilization
- Reproduction
- Body lenght
=> intervals: Days 0, 5, 12 and 20 and of the expired test preparations on Days 1, 6, 13 and 21

TEST CONCENTRATIONS
- saturated solution of the test item i.e. 0.56 µg/L

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.56 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Details on results:

- Behavioural abnormalities: none
- Observations on body length and weight: none
- Other biological observations: none
- Mortality of control: none
- Other adverse effects control: none
- Immobilisation of control: none
- Abnormal responses: none

 

Summary of Findings Following the Exposure of Daphnia magna for 21 Days

Geometric Mean Measured Concentration (μg/L)	Parental (P1) Generation Mortalities (Initial Population = 10 – Control Group) (Initial Population = 9 – Test Group)			Total Number of Live Young	Number of Live Young from Parents Surviving to the End of the Test		Number of Live Young at the End of the Test Excluding Parents that were Accidental or Inadvertent Mortalities
	Total	Accidental	Inadvertent		Total	Average per Parent	Total	Average per Parent
Control	1	0	1	1463	1463	163	1463	163
0.052	1	0	1	1393	1311	164	1311	164

 

Summary of Daily Observations

Day	Geometric Mean Measured Concentration (μg/L)
	Control		0.052
	Adults Surviving	Live Young	Adults Surviving	Live Young
1	10	0	10		0
2	10	0	10		0
3	10	0	10		0
4	10	0	10		0
5	10	0	10		0
6	10	0	10		0
7	10	0	10		0
8	10	184	10		159
9	10	0	10		0
10	10	0	10		1
11	10	251	10		232
12	10	1	10		0
13	10	28	10		0
14	10	326	10		336
15	10	0	10		0
16	10	9	10		0
17	10	404	10		410
18	10	0	10		0
19	10	0	10		0
20	9	385	10		358
21	9	0	10		0
TOTALS	9	1588	10		1496

 

 

Body Length of Surviving Adults at Day 21

Geometric Mean Measured Concentration (μg/L)	Individual Daphnia Lengths (mm)
	1	2	3	4	5	6	7	8	9	10	Av	SD
Control	4.6	4.7	4.5	4.5	4.6	4.6	-	4.4	4.7	4.5	4.6	0.1
0.56	4.4	4.6	4.5	4.7	4.4	4.4	4.4	4.5	4.5	4.6	4.5	0.1

 

 

Reconstituted Water – Elendt M4 Medium

Main Compounds mg/L		Trace Elements* μg/L			Vitamins μg/L
CaCl2.2H2O	293.8	B	H3BO3	500	Thiamine HCl	75
MgSO4.7H2O	123.3	Fe	FeSO4.7H2O†	200	Cyanocobalamine (B12)	1.0
KCl	5.8	Mn	MnCl2.4H2O	100	Biotin (B6)	0.75
NaHCO3	64.8	Li	LiCl	50
Na2SiO3.9H2O	10.0	Rb	RbCl	50
NaNO3	0.274	Sr	SrCl2.6H2O	50
KH2PO4	0.143	Br	NaBr	12.4
K2HPO4	0.184	Mo	Na2MoO4.2H2O	25.2
		Cu	CuCl2.2H2O	6.4
		Zn	ZnCl2	6.3
		Co	CoCl2.6H2O	2.5
		I	KI	2.5
		Se	Na2SeO3	1.0
		V	NH4VO3	0.3
		EDTA	Na2EDTA.2H2O	2500

Water Hardness: 2.5 mmol/L (= 250 mg/L as CaCO3) Alkalinity: 0.9 mmol/L

 

 

validation criteria

	Required	Actual
Control mortality	=<20%	10%
Mean number of live young per surviving adult (control group)	>=60 after 21 days	157
Coefficient of variation for control group*	=< 25%	7%
Ephippia produced	0	0
Dissolved oxygen	>3 mg O2/L	≥8.5 mg O2/L
pH (control group)	6 to 9 Variation =< 1.5	7.7 to 8.4 0.7

Validity criteria fulfilled:

yes

Remarks:

For further details please refer to “Any other information on results incl. tables”.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Effect concentration:

>= 0.56 µg/L

Additional information

One study is available assessing the long-term toxicity of (Z)-N-Octadec-9-enylhexadecan-1-amide (CAS No. 16260-09-6)  to aquatic invertebrates. The chronic toxicity of the substance was investigated according to OECD Guideline No. 211 in a semi-static limit test. Invertebrates were exposed for 21 days to a nominal test concentration of 100 % v/v. The test concentrations was analytically verified by LC-MS/MS. No effects on survival and reproduction of the Daphnids were observed. The determined NOEC (21 d) was≥0.56 µg/L (geom. mean meas.)