Isohexadecyl 12-[(1-oxooctadecyl)oxy]octadecanoate

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:

key study

Study period:

20 Apr - 24 Apr 1998

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

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Two stock solutions were prepared in water at nominal 1 and 100 mg/L. applying magnetic stirring for ca. 23 h to achieve maximum soluble fraction of the test substance in the test medium. Subsequently, these stock solutions were transferred to a separating funnel and left tot stabilize for ca. 4 h. The water phase in the middle of the separating funnel was used for testing. Both solutions were clear and colourless.
- Eluate: no
- Differential loading: yes
- Controls: yes, water control

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: carp
- Source: Obtained from Bio International, Roermond, The Netherlands (F1 from a single parent-pair nred om UV-treated water)
- Length at study initiation: 2.09 +/- 0.10 cm
- Weight at study initiation: 0.22 +/- 0.04 g
- Feeding during test: none

ACCLIMATION
- Acclimation period: At least 12 days after delivery.
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: Commercial fish feed "Trouvit"
- Feeding frequency: daily
- Health during acclimation (any mortality observed): Mortality seven days prior to the start of the test was less than 5%.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

250 mg CaCO3/L

Test temperature:

20.1 - 20.6 °C

pH:

7.8 - 8.1

Dissolved oxygen:

6.9 - 9.3 mg O2/L

Nominal and measured concentrations:

Nominal: 0, 10 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: all-glass vessels
- Material, size, headspace, fill volume: all glass, 4 L, headspace: 1.5 L, fill volume: 2.5 L
- Aeration: no
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.77 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: ISO-medium, formulated using Milli-RO water (tap water purified by reverse osmosis) with the following composition: Ca2+ 80 mg/L, Mg2+ 12 mg/L, Na+ 15 mg/L, K+ 3 mg/L, Cl- 145 mg/L, SO4 2- 49 mg/L, HCO3 47 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: Oxygen, pH, nitrate and nitrite and ammonia concentration were measured once a week.

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

EFFECT PARAMETERS MEASURED: Mortality was observed after 2, 24, 48, 72 and 96 h.

Reference substance (positive control):

yes

Remarks:

pentachlorophenol

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accommodated Fraction (WAF)

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: A thin test substance film was observed on the surface after 24 h for the 10 mg/L test concentration after 24 h. A test substance film was observed on the surface for the 100 mg/L test concentration after 24 h.

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Mortality: yes
- LC50: Between 0.10 - 0.15 mg/L

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

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

Adequacy of study:

key study

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Water Accommodated Fraction (WAF)

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

Source: CAS 93803-87-3, Croda, 1998, C. carpio, 96 h, RL1

Conclusions:

No effects up to the limit of water solubility (< 0.05 mg/L; OECD 203, C. carpio); read-across

Description of key information

No effects up to the limit of water solubility (1.39 µg/L, 20 °C; OECD 203, C. carpio); read-across

Additional information

There is no study available assessing the short-term toxicity of the target substance Isohexadecyl 12-[(1-oxooctadecyl)oxy]octadecanoate (CAS 97338-28-8) to fish. Therefore, read-across to the structurally related source substance 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was conducted in accordance with Regulation (EC) No. 1907/2006 Annex XI, 1.5. The source substance is characterized by similar but smaller fatty acid esters and is therefore considered a suitable representative for the assessment of the short-term toxicity of the target substance to fish. A detailed justification of the analogue approach is provided in IUCLID section 13.

The available GLP study with the source substance 2-octyldodecyl isooctadecanoate (CAS 93803-87-3) was conducted according to OECD guideline 203 and GLP (Croda, 1998) with the carp Cyprinus carpio. Water Accommodated Fractions of nominal 10 and 100 mg/L were prepared and tested under static conditions. A chemical analysis of the test substance concentrations in the test vessels was not possible because no analytical method could be established due to the very low water solubility to detect test concentrations. No mortality was observed after 96 h and therefore, a LL50 of > 100 mg/L (nominal) was derived. Based on this result it can be concluded that no toxicological effects on fish are expected up to the limit of water solubility for the source substance 2-octyldodecyl isooctadecanoate.

Based on the structural and chemical similarity of the target and source substance, the target substance is expected to exhibit a similar ecotoxicological profile. Therefore, it can be concluded that the target substance Isohexadecyl 12-[(1-oxooctadecyl)oxy]octadecanoate (CAS 97338-28-8) does not cause short-term effects to fish up to the limit of water solubility. Moreover, experimental studies are a technical challenge due to physico-chemical substance properties.