Carboxylic acids, C5-9

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:

Study performed in 1993.

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Only short abstract available

Qualifier:

according to guideline

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

no

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: Bluegill sunfish
- Weight at study initiation (mean and range, SD): 0.2 g

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 105 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

60 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

not specified

Conclusions:

The 96-h LC50 was 105 mg/L.
Nonanoic acid is one of the main constituents of the target UVCB substance.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

Study performed in 1993.

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data from reliable source

Qualifier:

according to guideline

Guideline:

EPA OPP 72-1 (Fish Acute Toxicity Test)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

no

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout
- Weight at study initiation (mean and range, SD): 0.98 g

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

91 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 68-121 mg/L

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

40 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

The 96-h LC50 was 91 mg/L.
Nonanoic acid is one of the main constituents of the target UVCB substance.

Executive summary:

The acute toxicity of nonanoic acid was tested on rainbow trout (Oncorhynchus mykiss) according to EPA OPP guideline 72 -1c. There is no detailed information on the number of test concentrations and analytical verification of test concentrations. The LC50 is slightly lower than 100 mg/L: 96 -h LC50: 91 mg/L (95% CL: 68 -121 mg/L); 96 -h NOEC: 40 mg/L.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): n-octanoic acid
- Substance type: acid
- Physical state: Liquid

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control (0 mg/L) ; 22 ; 32 ; 46 ; 68 and 100 mg/L
- Sampling method: tank water from each tank was analysed at 0 h (fresh media) and 24 h(expired media)
- Sample storage conditions before analysis: not indicated, but probably assayed right after sampling

Details on test solutions:

Test solutions with 22, 32, 46, 68 and 100 mg/l of the test materia were prepared and tested

Test organisms (species):

Oryzias latipes

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

Measured water temperature ranged between 23 - 25°C (min-max)

pH:

Measured pH ranged between 6 - 8.5 (min-max)

Nominal and measured concentrations:

Measured concentration with HPLC

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

51 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

Six groups of 10 medaka (Oryzias latipes) were exposed to graded concentrations of octanoic acid (0 ; 22 ; 32 ; 46 ; 68 and 100 mg/L) with daily water renewal. After 96 h exposure, all the fish of the 68 and 100 mg/L group died. No other fish died. LC50 was then estimated at 51 mg/L.

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1989

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Qualifier:

no guideline followed

Principles of method if other than guideline:

To investigate the quantitative structure-activity relationship (QSARs) for the acute toxicity of fatty acids and their sodium salts to aquatic organisms, red killifish (Oryzias latipes) and gammarus (Hyale plumulosa) were studied upon their sensitivity to a series of the acids and the sodium salts.Studies on red killifish was conducted both under saline and fresh water conditions. Good QSARs of fatty acids were obtained using an zoctanol/water partition coefficient as the single parameter. The log LC50 of fatty acid salts with C8 to C12 carbon chain length was linearly related to a logarithm of the critical micelle concentrations (CMCs).

GLP compliance:

not specified

Specific details on test material used for the study:

Caprylic acid as reported in this publication without any other detail

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: octanoic acid was dissolved in artifical sea water by adding 10 g/L and mixing in an Erlenmeyer flask for 24 h with a magnetic bar at room temperature (25 ± 2 °C). The mixture was left still for a few hours and the upper layer was remoced with a capillary pipette. The lower layer was used for testing.
For the freshwater test octanoic acid was disolved with Tween 80 (a dispersant, 10 times more of the testing concentration).

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: Red killifish
- Source: commercial source
- Length at study initiation: approximately 2.5 cm
- Weight at study initiation: approximately 0.2 g
- Feeding during test: feeding was stopped one day prior to the test
- Food type: commercial fish food

ACCLIMATION
- Acclimation period: Although Oryzias latipes is a freshwater fish, it was used in a marine test. First the fish were kept under laboratory conditions in freshwater for more than 2 weeks. Then fish were acclimated to sea water by changing salt concentrations from 0 to 10 per mille (kept at 10 per mille for more than 4 days), to 20 per mille (kept at 20 per mille for more than 4 days) and to the final salinity of 30 per mille (kept for more than 7 days before test start)

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

51 mg/l

Test temperature:

23 - 27 °C

pH:

freshwater: 7.2
saltwater: 8.2

Dissolved oxygen:

If dissolved oxygen was < 60 % of air saturation, aeration was provided once for 5 min at 24 h intervals.

Salinity:

30 per mille

Nominal and measured concentrations:

Animals were exposed to a geometric series of concentrations of the test chemical (max. 1000 mg/L), but when LC50 values of the test chemicals were close to or higher than the saturated concentrations, animals were exposed only to the saturated solutions and the half-dilution of the saturated solutions.

Details on test conditions:

TEST SYSTEM
- Material, size, headspace, fill volume: 2 L test water
- Aeration: if oxygen saturation was < 60% of air saturation aeration for 5 min, 24 h interval
- Renewal rate of test solution: no, static test
- No. of organisms per vessel: 10

OTHER TEST CONDITIONS
- Photoperiod: 12 h light/12 h dark

EFFECT PARAMETERS MEASURED: lethal effects

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

150 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

in sea water

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

57 mg/L

Nominal / measured:

not specified

Conc. based on:

not specified

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

fresh water

Validity criteria fulfilled:

not specified

Conclusions:

The LC50 of caprylic acid after 48 h was 150 mg/l in marine water and 57 mg/l in freshwater

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

- Name of test material (as cited in study report): n-Heptanoic acid
- Substance type: acid
- Physical state: Liquid
- Analytical purity: >97.7%
- Lot/batch No.: FHH02

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control (0 mg/L) ; 10 ; 18 ; 32.1 ; 56 and 100 mg/L
- Sampling method: tank water from each tank was analysed at 0 h (fresh media) and 24 h(expired media)
- Sample storage conditions before analysis: not indicated, but probably assayed right after sampling

Vehicle:

yes

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: medaka
- Source: Amijima Fishing (Amijima-nishi 5-18-1, Hamakita Ward, Yokohama City, Kanagawa prefecture)
- Length at study initiation (length definition, mean, range and SD): The initial mean standard length was 1.80 - 2.31 cm (min-max)
- Weight at study initiation (mean and range, SD): The initial mean weight was 0.066 - 0.173 g (min-max)
- Method of breeding: controlled conditions
- Feeding during test: None

ACCLIMATION
- Acclimation period: 6 weeks
- Acclimation conditions (same as test or not): same as test except that fish were not fed during the test
- Type and amount of food: Tetramin by Tetra Werke GmBH (feeding rate was 2% of body mass per day)
- Feeding frequency: daily
- Health during acclimation (any mortality observed): Less than 5% mortality

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

68 mg/L as CaCO3

Test temperature:

Measured water temperature ranged between 23.2 - 23.7°C (min-max)

pH:

Measured water pH ranged between 5.3 - 7.4 (min-max)

Dissolved oxygen:

Measured dissolved oxygen ranged between 7.3 - 8.6 mg/L (min-max)

Nominal and measured concentrations:

Nominal tested concentrations were 0 (control) ; 10 ; 18 ; 32 ; 56 and 100 mg/L. No heptanoic acid was found in the control.
Initial concentration were 0 ; 10.6 ; 18.4 ; 31.2 ; 60.3 and 116 mg/L
After 24 h: 0 ; 8.9 ; 14.9 ; 28.9 ; 52.2 mg/L. The 100 mg/L group was not measured due to fish 100% mortality after only one day exposure.

Details on test conditions:

TEST SYSTEM
- Test vessel: aquaria
- Material, size, headspace, fill volume: glass, 5 L
- Aeration: yes
- Renewal rate of test solution (frequency/flow rate): daily (semi-static conditions)
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: < 1 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: laboratory tap water filtered, dechlorinated and softened by passage through an Elga water purification system.
- Chlorine: <0.01 mg/L
- Alkalinity: 110 mg/L CaCO3
- Ca/mg ratio: 3
- Conductivity: 160 µS/cm

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16L:8D
- Light intensity: 1000 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : fish mortality and abnormal behaviour, at 24 , 48 , 72 and 96 h after the beginning of the experiment.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Test concentrations: 0 ; 10 ; 18 ; 32.4 ; 56 ; 100 mg/L

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

74.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

CI=[56;100]

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

56.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

All fish from the 100 mg group died. No other fish from any other group died.

Results with reference substance (positive control):

none

Reported statistics and error estimates:

LC50 was calculated as the geometric mean of the nominal concentrations of the 56 and 100 mg/L groups.

Validity criteria fulfilled:

yes

Conclusions:

After exposure to graded concentrations of heptanoic acid, fish LC50 was estimated at 74.8 mg/L.

Executive summary:

Six groups of 10 medaka (Oryzias latipes) were exposed to graded concentrations of heptanoic acid (0 ; 10 ; 18 ; 32 ; 56 and 100 mg/L) with daily water renewal. After 96 h exposure, all the fish of the 100 mg/L group died. No other fish died. LC50 was estimated at 74.8 mg/L

Description of key information

The lowest value of LC50 after 96 h was chosen for the assessment for the fresh water. For the marine water the only available LC50 was used (relative to octanoic acid).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

51 mg/L

Marine water fish

Marine water fish

Effect concentration:

150 mg/L

Additional information

 Nonanoic Acid

There are two reliable studies available, which confirm that the 96-h LC50 is around 100 mg/L (OPP, 2000). The study from Brooke et al. (1984) was selected as key study due to the detailed documentation and the analytical verification of test item concentrations.

Oncorhynchus mykiss: 96-h LC50 = 91 mg/L (static; OPP, 2000)

Lepomis macrochirus: 96-h LC50 > 105 mg/L (static; OPP, 2000)

Heptanoic Acid

The reported study determined the acute toxicity of n-heptanoic acid to medaka (Oryzias latipes), according to the OECD 203 guidelines. The toxicity was higher to this species, as LC50 was calculated as 74.8 mg/L.

Octanoic Acid

In the first study six groups of 10 medaka (Oryzias latipes) were exposed to graded concentrations of octanoic acid (0 ; 22 ; 32 ; 46 ; 68 and 100 mg/L) with daily water renewal. After 96 h exposure, all the fish of the 68 and  100 mg/L group died. No other fish died. LC50 was then estimated at 51 mg/L.

In the second one the LC50 of caprylic acid , after 48 h , was 150 mg/l in marine water and 57 mg/l in freshwater

Please consider that nonanoic acid, octanoic acid, heptanoic acid are the main constituents of the target UVCB substance.