Amides, coco, N,N-bis(hydroxyethyl); C10-12 and C18-unsatd. DEA

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

From February 15, 1996 to April 13, 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

No analytical dose verification

Justification for type of information:

Refer to section 13 for details on the read-across justification. The study with the read across substance is considered sufficient to fulfil the information requirements as further explained in the provided endpoint summary.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Direct dispersion in water
- Solvent control: Dechlorinated tap water
- Chemical name of vehicle (organic solvent): Water
- Concentration of vehicle in test medium (stock solution): 500 mg/L
- Preparation of test solution: Test material (500 mg) was dispersed in 1 L of dechlorinated tap water to give stock solution from which aliquots (40, 72, 128, 224 and 400 mL) were separately dispersed in 20 L (final volume) of dechlorinated tap water to give the test series 1.0, 1.8, 3.2, 5.6 and 10 mg/L.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Source: Donnington Fish Farm, Upper Swell, Gloucestershire, UK
- Age at study initiation (mean and range, SD): Juvenile
- Length at study initiation (length definition, mean, range and SD): 5.0 cm (SD = 0.4)
- Weight at study initiation (mean and range, SD): 1.57 g (SD = 0.33)
- Feeding during test: No


ACCLIMATION
- Acclimation period: 8 d
- Acclimation conditions (same as test or not): Maintained in a glass fiber tank with a single pass water renewal system
- Type and amount of food: Commercial trout pellets, discontinued 24 h prior to definitive study

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

100 mg/L as CaCO3

Test temperature:

14 ± 1 °C

pH:

7.6-7.9

Dissolved oxygen:

≥ 9.1 mg O2/L

Nominal and measured concentrations:

Nominal concentrations:
- Range finding study: 1.0, 10 and 100 mg/L
- Definitive study: 1.0, 1.8, 3.2, 5.6 and 10 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: Closed
- Material, size, headspace, fill volume: 20 L glass exposure vessel
- Aeration: Aerated via narrow bore glass tubes
- Renewal rate of test solution (frequency/flow rate): Daily
- No. of organisms per vessel: Three in range finding study, ten in definitive study
- No. of vessels per concentration (replicates): Two
- No. of vessels per vehicle control (replicates): Two
- Biomass loading rate: 0.79 g bw/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dechlorinated tap water


OTHER TEST CONDITIONS
- Photoperiod: 16 h light and 8 h darkness


EFFECT PARAMETERS MEASURED (with observation intervals if applicable): 3, 6, 24, 48, 72 and 96 h post-exposure


TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline: Not applicable
- Range finding study
- Test concentrations: 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: Results from range-finding study showed no mortalities at 1 mg/L. However, mortalities were observed at 10 & 100 mg/L.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: Behavioural responses (increased pigmentation, fish swimming at the bottom of the test vessels, loss of equilibrium and the presence of moribund fish) to exposure were observed at test concentration ≥ 1.8 mg/L.
- Mortality of control: No
- Effect concentrations exceeding solubility of substance in test medium: No

Sublethal observations / clinical signs:

Table 1: Cumulative mortality data in the range-finding study

Nominal concentration (mg/L)	Cumulative Mortality (Initial Population: 3)
	24 h	48 h	72 h	96 h
Control	0	0	0	0
1.0	0	0	0	0
10	3	3	3	3
100	3	3	3	3

 

Table 2: Cumulative mortality data in the definitive study

Nominal concentration (mg/L)	Cumulative Mortality (Initial Population: 10)						% mortality
	3 h	6 h	24 h	48 h	72 h	96 h	96 h
Control	0	0	0	0	0	0	0
1.0	0	0	0	0	0	0	0
1.8	0	0	0	0	0	0	0
3.2	0	0	0	0	5	10	100
5.6	0	0	2	10	10	10	100
10	0	0	10	10	10	10	100

* R1-R2 = Replicates 1 & 2

 

Table 3: Behavioural responses to exposure in the definitive study

 

Nominal concentration (mg/L)	Behavioural Responses*	Time (h)
		3	6	24	48	72	96
Control	No abnormalities detected
1	No abnormalities detected
1.8	Increased pigmentation					2/10
	Swimming at bottom with
	increased pigmentation						4/10
3.2	Swimming at bottom with
	increased pigmentation				8/10	2/5	A/D
	Moribund				2/10	3/5
5.6	Swimming at bottom		5/10	8/8	A/D
	Increased pigmentation			8/8
10	Swimming at bottom	10/10	5/10	A/D
	Loss of equilibrium		5/10

* Unless stated no adverse reactions were observed.

A/D = All fish dead

 

Table 4: Results based on the mortality data in the definitive study

Time (h)	LC50 (mg/L)	95% Confidence Limits (mg/L)
3	>10	-
6	>10	-
24	6.7	5.8 -7.8
48	4.2	3.2 -5.6*
72	3.2	2.6 -3.8
96	2.4	1.8 -3.2*

* Concentrations resulting in 0 and 100 % mortality respectively

 

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, the nominal 96 h LC50 and NOEC were determined to be 2.4 and 1.0 mg/L, respectively.

Executive summary:

A study was conducted to evaluate the acute toxicity of the read across substance, C8-18 and C18-unsatd. DEA, to rainbow trout (Oncorhynchus mykiss) according to OECD Guideline 203, in compliance with GLP. Based on the results of a range-finding study, groups of 20 rainbow trout were exposed to the read across substance at nominal concentrations of 1.0, 1.8, 3.2, 5.6 and 10 mg/L for 96 h under semi-static conditions. Mortality and adverse reactions were determined at 3, 6, 24, 48, 72 and 96 h. No analytical dose verification was conducted. Mortality occurred as of 72 h at 3.2 mg/L and as of 24 h at the two higher doses. Behavioural responses (increased pigmentation, fish swimming at the bottom of the test vessels, loss of equilibrium and presence of moribund fish) were observed as of 1.8 mg/L. Under the study conditions, the nominal 96 h LC50 and NOEC values were determined to be 2.4 and 1.0 mg/L, respectively (Wetton, 1996). Based on the results of the read across study, similar 96 h LC50 and NOEC values are considered for the test substance, C10-12 and C18-unsatd. DEA..

Description of key information

Based on the results of the read across study, the 96 h LC50 and NOEC values of the test substance, C10-12 and C18-unsatd. DEA, for toxicity to fish is considered to be 2.4 and 1.8 mg/L (nominal) respectively.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

2.4 mg/L

Additional information

A study was conducted to evaluate the acute toxicity of the read across substance, C8-18 and C18-unsatd. DEA, to rainbow trout (Oncorhynchus mykiss) according to OECD Guideline 203, in compliance with GLP.Based on the results of a range-finding study, groups of 20 rainbow trout were exposed to the read across substance at nominal concentrations of 1.0, 1.8, 3.2, 5.6 and 10 mg/L for 96 h under semi-static conditions. Mortality and adverse reactions were determined at 3, 6, 24, 48, 72 and 96 h. No analytical dose verification was conducted. Mortality occurred as of 72 h at 3.2 mg/L and as of 24 h at the two higher doses. Behavioural responses (increased pigmentation, fish swimming at the bottom of the test vessels, loss of equilibrium and presence of moribund fish) were observed as of 1.8 mg/L. Under the study conditions, the nominal 96 h LC50 and NOEC values were determined to be 2.4 and 1.0 mg/L, respectively (Wetton, 1996). Based on the results of the read across study, similar 96 h LC50 and NOEC values are considered for the test substance, C10-12 and C18-unsatd. DEA..