Fatty acids, C8-10

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

04 Jan- 08 Jan 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented study report which meets basic scientific principles

Qualifier:

according to guideline

Guideline:

other: Methods for acute toxicity tests with fish, macroinvertebrates, and amphibians (U.S. EPA, 1975)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Stock solution was prepared by adding 1.56 g test substance to distilled water and diluting to 1000 mL in a volumetric flask. Subsequently the solution was mixed on a magnetic stirrer for 30 min and then added to each test jar in the required amount. The test medium was also mixed for approximately 2 min.
- Controls: 1
- Evidence of undissolved material: At nominal concentrations of 14, 24 and 40 mg a.s./L the test material was not entirely dissolved.

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: bluegill sunfish
- Source: Commercial fish supplier in Connecticut (USA)
- Length at study initiation: mean: 34 mm (range 25 - 44 mm, n = 30)
- Weight at study initiation: mean: 0.39 g (range: 0.16 - 0.99 g, n = 30)
- Feeding during test: none

ACCLIMATION
- Acclimation period: 14 d
- Acclimation conditions: same as during test
- Type and amount of food: dry pelleted food, ad libitum
- Feeding frequency: daily except during 48 h prior to test
- Health during acclimation: mortality during the 48 h prior to test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

49 mg/L

Test temperature:

22 ± 1 °C

pH:

6.4 - 7.3

Dissolved oxygen:

0.3 - 9.4 mg/L (= 3.4 - 100%)

Nominal and measured concentrations:

nominal: 3.1, 5.2, 8.6, 14, 24 and 40 mg a.s./L

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume of test vessel: 19.6 L glass jar containing 15 L test medium
- Aeration: no aeration provided
- No. of organisms per vessel: 10
- No. of vessels per concentration: 1
- No. of vessels per control: 1

OTHER TEST CONDITIONS
- Photoperiod: 16 h light/ 8 h dark

EFFECT PARAMETERS MEASURED: mortality and sublethal effects every 24 h

Reference substance (positive control):

yes

Remarks:

sodium lauryl sulfate

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% conficdence interval: 17 .- 31 mg a.s./L

Details on results:

- Behavioural abnormalities: fish were lethargic, respiring repidly and/or at water surface
- Mortality of control: no fish died in the control
- Effect concentrations exceeding solubility of substance in test medium: At nominal concentrations of 14, 24 and 40 mg a.s./L the test material was not entirely dissolved.

Results with reference substance (positive control):

- LC50: 12 mg sodium lauryl sulfate/L, confidence interval: 10 - 15 mg/L

Sublethal observations / clinical signs:

Table 1: Mortality and sublethal effects of the test substance to fish

Time after test start [h]	Effects	Nominal test concentrations [mg a.s./L]
		0	3.1	5.2	8.6	14	24	40
24	m	0	0	0	0	0	0	0
	r		×	×	×	×	×	×
	l							×*
	s
	f
	c
48	m	0	0	0	0	0	0	0
	r		×	×	×	×	×	×
	l				×	×	×	×
	s							×
	f
	c		×	×	×	×	×	×
72	m	0	0	0	0	30	10	20
	r		×	×	×	×	×	×
	l			×	×	×	×	×
	s					×	×	×
	f
	c		×	×	×	×	×	×
96	m	0	0	0	0	30	50	80
	r		×	×	×	×	×	×
	l				×	×	×	×
	s					×	×	×
	f					×	×	×
	c		×	×	×	×	×	×

m = mortality [%]

r = all fish were respiring rapidly

l = all fish were lethargic

s = all fish were at the test solutions surface

f = fine white flocculent was observed in the test solution

c = test solution was cloudy

* not all, but 2 fish were lethargic

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

17 Nov - 21 Nov 1977

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given

Qualifier:

according to guideline

Guideline:

other: EPA-660/3-75-009, Methods for Acute Toxicity Tests with Fish Macroinvertebrates and Amphibians. 1975

Principles of method if other than guideline:

Acute (96h) toxicity test with Lepomis macrochirus conducted under static conditions.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: bluegill sunfish
- Source: commercial hatchery in Nebraska (USA)
- Age at study initiation: 5 months old
- Length at study initiation: mean 34 mm (range 26 - 40 mm)
- Weight at study initiation: mean 0.41 g (range 0.29 - 0.52 g)
- Feeding during test: none

ACCLIMATION
- Acclimation period: 24 h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

42 mg CaCO3/L

Test temperature:

23.0 ± 0.5 °C, determined at test start and every 48 h

pH:

5.50 - 7.47, determined initially and every 48 h in the control, 100 mg/L, 32 mg/L and 10 mg/L

Dissolved oxygen:

0.7 - 9.5 mg/L, determined initially and every 48 h in the control, high, medium and low toxicant concentrations

Nominal and measured concentrations:

nominal: 10, 18, 32, 56 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, size, headspace, fill volume: 5 gallon, chemically clean glass jars containing 15 L test medium
- No. of organisms per vessel: 10
- No. of vessels per concentration: 1
- No. of vessels per control: 1
- Biomass loading rate: 0.27 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: water obtained from a well on the Tarrytown site, treated with a Continental Reverse Osmosis water System, afterwards deionised, pH and hardness adjusted.

OTHER TEST CONDITIONS
- Adjustment of pH: yes

EFFECT PARAMETERS MEASURED: mortality and sublethal effects

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

18.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval: 15.6 - 22.8 mg/L

Details on results:

- Other biological observations: Fish exposed to concentrations of 18 mg/L and higher became darkly discoloured, irritated and exhibited sounding initially with surfacing behaviour after 72 h.
- Mortality of control: 0

Sublethal observations / clinical signs:

Table 1: Mortality of fish [%]

Time after test start [h]	Test substance concentration [mg/L]
	0	10	18	32	56	100
24	0	0	0	100	100	100
48	0	0	0	100	100	100
96	0	0	40	100	100	100

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

07 Jun - 11 Jun 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Remarks:

according to the Japanese GLP Standard

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 20 mg/L
- Sampling method: 10 mL test solution was sampled directly from each test vessel at test initiation and after 48 hours.
- Sample storage conditions before analysis: analysis was conducted immediately after sampling, no storage

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test substance was dissolved in vehicle, and this stock solution was diluted in dilution water and stirred for 1 hour.
- Controls: dilution water with/without vehicle
- Chemical name of vehicle: dimethylformamide
- Concentration of vehicle in test medium: 0.1 mL/L
- Evidence of undissolved material: not observed

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: Medaka
- Source: Izumoto fish shop
- Length at study initiation: 2.1 cm (2.0 - 2.3 cm)
- Weight at study initiation: 0.19 g (0.16 - 0.21 g)
- Feeding during test: no food

ACCLIMATION
- Acclimation period: > 12 days
- Acclimation conditions: same as test
- Type and amount of food: Tetramin
- Health during acclimation: No mortality was observed during 7 days before exposure.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96

Hardness:

55.2 mg/L (as CaCO3)

Test temperature:

23.3 - 23.9 °C (24 ± 1 °C)

pH:

7.5 - 8.1

Dissolved oxygen:

5.6 - 8.2 mg/L (more than 60% of saturated oxygen)

Nominal and measured concentrations:

nominal concentration: 20 mg/L
measured concentration: 16 mg/L (geometric mean)

Details on test conditions:

TEST SYSTEM
- Test vessel: 5L glass fish tank
- Material, size, headspace, fill volume: glass, 21*16*23 cm, 5 L
- Aeration: no
- Renewal rate of test solution: once in 48 hours
- No. of organisms per vessel: 10
- No. of vessels per concentration: 1
- No. of vessels per control: 1
- No. of vessels per vehicle control: 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: charcoal-treated, dechlorinated and aerated tap water in Takarazuka, Japan
- Alkalinity: 55 mg/L
- Ca/Mg ratio: 16/3.3
- Culture medium different from test medium: same as test medium
- Intervals of water quality measurement: pH, oxygen content and temperature of test solutions were determined at 0, 24, 48 (both before and after renewal), 72 and 96 hours.


OTHER TEST CONDITIONS
- Photoperiod: 16 h light, 8 h dark

EFFECT PARAMETERS MEASURED: mortality observed daily

TEST CONCENTRATIONS
- Justification for using less concentrations than requested by guideline: 20 mg/L was the maximum concentration to be dissolved uniformly in dilution water with vehicle (0.1 mg/L).
- Range finding study: performed
- Test concentrations: 0, 0.2, 2.0, 20 mg/L
- Results used to determine the conditions for the definitive study: no mortality and no toxicity was observed

Reference substance (positive control):

yes

Remarks:

copper sulfate pentahydrate (analytical grade)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 16 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: no abnormality was observed
- Observations on body length and weight: not determined
- Other biological observations: no abnormality was observed
- Mortality of control: 0%
- Other adverse effects control: not observed
- Abnormal responses: not observed

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- LC50: 4 mg/L

Sublethal observations / clinical signs:

Table 1: Measured Concentratioin of Decanoic acid

Nominal Concentration (mg/L)	Measured Concentration (mg/L)			Percent of nominal
	0 Hours (new)	48 Hours (old)	Mean
Control	<0.2	<0.2	-	-
Solvent Control	<0.2	<0.2	-	-
20	23	11	16	80

new: Freshly prepared test solutions

old: Test solutions after 48 -hours exposure period

Table 2: Mortality of Medaka (Oryzias latipes)

Mean measured concentration (mg/L)	Cumulative Number of Dead Fish (Percent Mortality)
	24 Hours	48 Hours	72 Hours	96 Hours
Control	0 (0)	0 (0)	0 (0)	0 (0)
Solvent Control	0 (0)	0 (0)	0 (0)	0 (0)
16	0 (0)	0 (0)	0 (0)	0 (0)

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

Please refer to the category justification provided in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

18.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence interval: 15.6 - 22.8 mg/L

Remarks:

Source: CAS 334-48-5, 1977

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% conficdence interval: 17 .- 31 mg a.s./L

Remarks:

Source: 124-07-2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 16 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Source: CAS 334-48-5, 1999

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 20 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Source: CAS 334-48-5, 1999

Description of key information

LC50 (96 h) = 18.9 mg/L (nominal), based on mortality of Lepomis macrochirus; RA CAS 334 -48 -5

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

18.9 mg/L

Additional information

No studies investigating the short term toxicity of the substance fatty acids, C8 -10 to fish are available. Therefore, good quality read across data from the two main constituents (decanoic and octanoic acid) of the substance are used. Three studies are available and provide in the frame of a WoE clear indications towards the short term toxicity of the substance on fish.  

In the first study conducted with the constituent decanoic acid (1999) Oryzias latipes was exposed in a semi-static system to only one single test item concentration of 20 mg/L (nominal) for 96 h. The experiment was conducted according to OECD guideline 203 and GLP. The test substance was dissolved in 0.1 ml/L dimethylformamide. The concentration of the test item in the solutions was monitored by GC-MS over time. The mean recovery of the test item concentration was 80%. The study showed no effects on the test organism resulting in an LC50 (96 h) of > 16 mg/L (meas., geom. mean). However, this result is very possibly attributed to the low concentration tested, as supported by the further available study, which was performed with higher concentrations of the substance decanoic acid.

In the second available study with the read across substance decanoic acid (1977), Lepomis macrochirus, was exposed for 96 h in a static test regime to higher test concentrations than the first listed study (0 (control), 10, 18, 32, 56 and 100 mg/L nominal) showing toxicity effects. The study was performed according to EPA-660/3-75-009, Methods for Acute Toxicity Tests with Fish Macroinvertebrates and Amphibians (1975) and resulted in an LC50 (96 h) of 18.9 mg/L (nominal). 

A further test (1982) is available with the read across substance octanoic acid. The toxicity to Lepomis macrochirus was tested under static conditions according to an EPA-method (1975, Methods for acute toxicity tests with fish macroinvertebrates, and amphibians). Nominal test concentrations of 0 (control), 3.1, 5.2, 8.6, 14, 24 and 40 mg/ L were applied. No analytical monitoring was performed. At all concentrations fish respired rapidly and the test solution was cloudy. In addition at the three highest concentrations, all fish were lethargic. After incubation time of 96 h, an LC50 of 22 mg/L (nominal) was determined.

 

In conclusion, the sum of the available data for the two main constituents of the substance give clear indications that short term toxicity of fatty acids, C8 -10 on fish is expected at concentrations higher than 18 mg/L.