Fatty acids, C16-18, isononyl esters

Sediment toxicity

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

sediment toxicity: short-term

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

Refer to read across justification provided in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

> 1 439.41 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other:

Remarks:

Source: CAS 85049-37-2, BASF, 2000, C. volutator

Conclusions:

Based on the available LC50 (10.0 d) > 1439.41 mg/kg sediment dw (nominal, OSPARCOM, RA CAS 85049-37-2), the target substance is expected to exhibit very low toxicity to sediment organisms.

Reference 2

Endpoint:

sediment toxicity: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 Jan - 07 Feb 2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: National guideline with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: OSPARCOM 1995, Paris Commission Guidelines for conducting sediment toxicity tests with the amphipod Corophium volutator

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on sediment and application:

PREPARATION OF SPIKED SEDIMENT
- Pooling or mixing of different substrates: Natural sediment collected and wet sieved through 0.6 mm mesh sieves, then allowed to settle in tall polyethylene containers; The supernatant is decanted and the sediment stored at 4°C
- Method of mixing: Sediment is homogenised, a subsample is taken for wet and dry weight determination
- Details of spiking: test substance mixed into dry sediment using solvent, dried sediment is then incorporated with wet sediment (mixing container), mixing vessel placed on platform shaker at 150 rpm for 3 hours and then equally distributed among the replicate vessels
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone, ethano or triethylene glycol (not further clarified in report)

Test organisms (species):

Corophium volutator

Details on test organisms:

TEST ORGANISM
- Source: collected from site in the Bay of Suckquoy, near Sebay Farm in Orkney
- Details on collection: Organisms gently sieved and held in plastic containers; in laboratory animals are transferred to ambient water to polythene tanks of approx. 200 L capacity, with gentle aeration at 15°C;
- Length of animals at beginning of exposure: approx. 5 mm length

ACCLIMATION
- Acclimation period: 3 to 14 days;
- Acclimation conditions (same as test or not): no
- Type and amount of food: detrital material
- Health during acclimation (any mortality observed): Mortality 4%

Study type:

laboratory study

Test type:

static

Water media type:

saltwater

Type of sediment:

natural sediment

Limit test:

no

Duration:

10 d

Exposure phase:

total exposure duration

Post exposure observation period:

not relevant

Hardness:

no data

Test temperature:

14.0-15.9 °C (14.2-16.4 in control)

pH:

7.75-8.03 (7.78-8.00 in control)

Dissolved oxygen:

95-98% (94-97% in control)

Salinity:

Conductivity: 48.9-55.5 mS/cm (approx. 3.75% salinity at 15°C)

Ammonia:

no data

Nominal and measured concentrations:

Nominal: 14.6, 146.75, 466.26, 1439.41 and 13932.35 mg/kg dry weight

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 1L glass beaker
- Sediment volume: 150 mL (approx. 2 cm depth of sediment)
- Overlying water volume: 850 mL
- Depth of sediment and overlying water: approx. 2 cm sediment
- Aeration: Stream of air bubbles released at a depth of 6 cm

EXPOSURE REGIME
- No. of organisms per container (treatment): 20
- No. of replicates per treatment group: 3
- No. of replicates per control / vehicle control: 5

OVERLYING WATER CHARACTERISTCS
- Type of water (e.g. deionized, ground water, sea water, Elendt medium acc. to OECD 219): Natural seawater, UV sterilised and filtered to 1 µm

SOURCE OF NATURAL SEDIMENT
- Location and description of sampling site: Bay of Suckquoy, near Sebay farm in Orkney

HANDLING OF NATURAL SEDIMENT
- Storage conditions: 4°C

OTHER TEST CONDITIONS
- Photoperiod: constant dim illumination

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality (missing animals counted as dead)

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 5 to 10

Reference substance (positive control):

no

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

> 1 439.41 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of test animals at end of exposure period: 53% of the animals were dead at the test substance concentration of 13932.35 mg/kg sed dw
- No LC50 was determined in the report

The mortality of Corophium volutator at the nominally tested concentrations in %:

	Mortality in %
Concentration in mg/kg dw	Replicate 1	Replicate 2	Replicate 3
14.6	0	0	0
146.75	10	0	0
466.26	0	0	5
1439.41	15	10	15
13932.35	55	50	55

Description of key information

LC50 (10 d) > 1439 mg/kg sediment dw (OSPARCOM, C. volutator); read-across

Additional information

There is no study available assessing the sediment toxicity of the target substance Fatty acids, C16-18, isononyl esters (CAS 91031-57-1). Therefore, read-across to the structurally related source substance Fatty acids, C16-18 and C18-unsatd., 2-ethylhexyl esters (CAS 85049-37-2) was conducted in accordance with Regulation (EC) No 1907/2006 Annex XI, 1.5. The source substance is considered a suitable representative for the assessment of the sediment toxicity of the target substance. A detailed read-across justification is provided in IUCLID section 13.

The available study was conducted according to the OSPARCOM guideline (Paris Commission Guidelines for conducting sediment toxicity tests with the amphipod Corophium volutator, 1995) and GLP. The marine test organism Corophium volutator was exposed to five, nominal test item concentrations ranging from 14.6 to 13932.35 mg/kg sediment dry-weight in a static system with natural sediment for 10 d. The derived LC50 value was > 1439.41 mg/kg sediment dry-weight.

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 Fatty acids, C16-18, isononyl esters (CAS 91031-57-1) has very low toxicity to sediment organisms. Moreover, the substance is readily biodegradable and the available acute and chronic data indicate no hazard to aquatic or terrestrial organisms. Therefore, long-term testing of sediment organisms is not considered necessary.