Fatty acids, C14-22, C16-24-alkyl esters

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

Refer to analogue justification provided in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

reproduction

Remarks on result:

other:

Remarks:

Source: Key, source, RA-A, CAS 3687-45-4, DHW, 2013, D. magna, 21 d, RL1

Duration:

21 d

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

Source: Key, source, RA-A, CAS 3687-45-4, DHW, 2013, D. magna, 21 d, RL1

Conclusions:

The retained effect concentration for the long-term toxicity to aquatic invertebrates is a NOELR (21 d) of ≥ 100.0 mg/L (nominal, OECD 211, read-across).

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

05 Jan - 22 May 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

GLP compliance:

yes (incl. QA statement)

Remarks:

Swiss Federal Office of Public Health, Bern, Switzerland

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Control, 100 mg/L
- Sampling method: Duplicate samples were taken from the freshly prepared test medium of the single test concentration and from the control at one treatment period of the first, second and last week of the test (day 0, 2, 7 and 16, respectively). To determine the maintenance of the test substance concentration in test medium, stability samples were taken at the end of two test medium renewal periods of 48 h (day 2 and 9) and at the end of two renewal periods of 72 h (days 5 and 19).
- Sample storage conditions before analysis: All samples were stored deep-frozen (at about -20 °C) and protected from light immediately after sampling.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A dispersion with the nominal concentration of 100 mg/L was prepared prior to the start of the test and prior to each medium renewal by dispersing 400 and 200 mg of the test item (dosed in the range of 400 to 401 mg on days 0, 7 and 16 and in the range of 200 to 201 mg on days 2, 5, 9, 12, 14 and 19) in 4000 and 2000 mL of test water under intense stirring for 96 h at room temperature in the dark to avoid photolytic degradation. After the 96 h stirring period, the test item was filtered through a membrane filter (Schleicher & Schuell, Type NC45, pore size 0.45 µm). The test medium was prepared just before the start of the test (= addition of daphnids) and before each test medium renewal.
- Eluate: no
- Differential loading: no
- Controls: yes, test medium control

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Originally supplied by the University of Sheffield/UK in 1992. Since this date, the clone is successfully bred at Harlan Laboratories.
- Age of parental stock (mean and range, SD): < 24 h
- Feeding during test
- Food type: food mixture containing a suspension of green algae of the species Scenedesmus subspicatus (freshly grown at the laboratory) and a fish food suspension. The fish food suspension was prepared by dispersing 10 g of powdered commercial fish diet (TETRA MIN Hauptfutter, obtained from TETRA-Werke, Melle, Germany) in 500 mL of test water. The suspension was allowed to stand for 4 hours. Then, 400 mL of the supernatant were taken, diluted 1:1 with test water and boiled. The suspension was stored deep frozen in small quantities until use.
- Amount: 0.20 mg TOC per Daphnia and day
- Frequency: daily
- Method of breeding: Each stock animal was maintained separately in a 100 mL glass beaker filled with about 80 mL culture medium and was transferred twice a week to fresh medium. The condition of the stock animals was frequently checked. No signs of stress were observed and the brood stock was healthy.

ACCLIMATION
- Acclimation period: The daphnids used for the test originated form parental daphnids that were at least 14 d old but not older than four weeks and were not first brood progeny.
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: same as test
- Feeding frequency: three times a week

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

21 d

Test temperature:

20 - 21 °C

pH:

7.7 - 8.1

Dissolved oxygen:

8.2 - 9.2 mg O2/L

Nominal and measured concentrations:

nominal: control, 100 mg/L
measured: < LOQ in the control and treatment

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- Type (delete if not applicable): covered with glass plates to reduce loss of water by evaporation and to avoid the entry of dust into the solutions.
- Material, size, headspace, fill volume: glass, 100 mL, headspace: 20 mL, fill volume: 80 mL
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): renewed on days 2, 5, 7, 9, 12, 14, 16 and 19.
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 20
- No. of vessels per control (replicates): 20

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water (Elendt M7 medium)
- Alkalinity: 0.9 mmol/L
- Water hardness: 250 mg/L as CaCO3
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light / 8 h dark (30 min transition period)
- Light intensity: 400 - 540 lux

EFFECT PARAMETERS MEASURED: Mortality and reproduction on days 0-2 and thereafter at least three times per week before renewal of test media. On the same dates, the test repliacates were observed for the number of living and dead offspring and for the presence of aborted eggs.

Reference substance (positive control):

no

Duration:

21 d

Dose descriptor:

NOELR

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

EL50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

WAF

Basis for effect:

mortality

Details on results:

- Mortality of parent animals: 0% in control; 5% in treatment
- Type and number of behavioural abnormalities: No visible abnormalities were observed during the test.
- No. of offspring produced after 21 d per female: 142 (mean, control); 137 (mean, treatment)
- Time to first brood release or time to hatch: day 9 in control and treatment

Reported statistics and error estimates:

Student t-test (one-sided smaller, α = 0.05) with the mean values of living offspring.

Description of key information

No effects up to the limit of water solubility(< 2.5 µg/L, 20 °C; OECD21, D. magna); read-across

Additional information

There is no study available, in which the long-term toxicity of the target substance fatty acids, C14-22, C16-24-alkyl esters (CAS 92797-30-3) to aquatic invertebrates was assessed. Therefore, read-across to the structurally related source substance (Z)-octadec-9-enyl oleate (CAS 3687-45-4) was conducted in accordance with Regulation (EC) No. 1907/2006 Annex XI, 1.5. The source substance is characterized by fatty acid esters of similar chain length and is therefore considered a suitable representative for the assessment of the chronic toxicity of the target substance to aquatic invertebrates. A detailed justification of the analogue approach is provided in IUCLID section 13.

The available study with the source substance (Z)-octadec-9-enyl oleate (CAS 3687-45-4) was conducted according to OECD 211 and GLP (Ecogreen, 2013). In a semi-static limit test,Daphnia magnawas exposed to a Water Accommodated Fraction (WAF) with a nominal loading concentration of 100 mg/L. After 21 d no effects on reproduction and mortality were recorded, resulting in a NOELR (21 d) of ≥ 100 mg/L. 0% mortality was recorded in the control whereas 5% mortality was observed in the treatment. This mortality is regarded as natural and is within the range tolerated by the test guideline. The chemical analysis resulted in concentrations below the analytical detection limit of 0.0423 mg/L reflecting the very low water solubility of the test item. Based on this result, it can be concluded that the source substance (Z)-octadec-9-enyl oleate (CAS 3687-45-4) does not cause chronic effects on aquatic invertebrates up to the limit of water solubility (< 0.05 mg/L).

 

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 fatty acids, C14-22, C16-24-alkyl esters (CAS 92797-30-3) does not cause long-term effects to aquatic invertebrates up to the limit of water solubility (< 2.5 µg/L).