Hydrocarbons, C17-C19, n-alkanes, <2% aromatics

Sediment toxicity

Link to relevant study record(s)

Reference

Endpoint:

sediment toxicity: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2006-10-03 to 2006-10-14

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Good guideline study. However, there is little information on sediment(collection, characteristics...) and organisms (collection, holding and acclimation).

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

other: PARCOM Protocols on Methods for the testing of chemicals used in the offshore industry. Part A: A sediment bioassay using an amphipod Corophium sp. (1995)

Deviations:

no

Principles of method if other than guideline:

Guideline study

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No test surrogate material is tested

Analytical monitoring:

not required

Details on sampling:

Not applicable (no analytical monitoring)

Vehicle:

yes

Details on sediment and application:

PREPARATION OF SPIKED SEDIMENT
- Natural sediment from the same unpolluted site as the amphipods (organic content: 3.3%; silt fraction: 73%), homogenized before preparing the test sediment.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone

- Spiked test sediment: 5 Ll acetone containing test substance added to 130 g pre-dried sediment. After the acetone had dried off in a fume cupboard, the sample was added to 460 g of damp sediment.

- Reference substance: fluoranthene dissolved in 5 mL of acetone added to app. 110 g pre-dried sediment.After the acetone had dried off in a fume cupboard, the sample was added to app. 510 g of damp sediment in a plastic bucket.

- The sediment in the blanks (with and without acetone) was treated like the test sediment but without adding test substance.

All sediments (test concentrations, reference substance and blanks) were prepared in plastic buckets. 130 mL of seawater was added to each bucket and the bucket were shaken (120 rpm) for 5 hrs.

Test organisms (species):

Corophium volutator

Details on test organisms:

TEST ORGANISM
- Details on collection: collected 23.09.2006 by Biotrix, Norway and transported by car and airplane to the laboratory.
- Size of animals at beginning of exposure: 5-10 mm long
- Feeding during test: no feeding

ACCLIMATION
- Acclimation period: 4 days (29.09-0.3.10.2006)
- Acclimation conditions (same as test or not): temperature 15+/-2 °C

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:

No post exposure observation

Hardness:

Not relevant (seawater study)

Test temperature:

15 +/- 2°C

pH:

8.1

Dissolved oxygen:

88-96 % saturation

Salinity:

34 per thousand

Ammonia:

No data provided

Nominal and measured concentrations:

Test substance nominal concentrations: 126, 308, 668, 1495 mg/kg dw

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 600 mL glass containers
- Weight of wet sediment: 200 g
- Overlying water volume: 450 mL

EXPOSURE REGIME
- No. of organisms per container (treatment): 9-10
- No. of replicates per treatment group: 3
- No. of replicates per control: 3
- No. of replicates per vehicle control: 3


OVERLYING WATER CHARACTERISTCS
- Natural sea water from an unpolluted site at about 80 m depth in Byfjord, filtrated through a sand filter
- Salinity: 34 per thousand


SOURCE OF NATURAL SEDIMENT
- same unpolluted site as the amphipods


HANDLING OF NATURAL SEDIMENT
- Time of collection: 23.09.2006


CHARACTERIZATION OF SEDIMENT
- Particle size distribution
- % silt: 73%
- Total organic content (%): 3.3


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.28

Reference substance (positive control):

yes

Remarks:

Fluoranthene

Duration:

10 d

Dose descriptor:

LC10

Effect conc.:

207 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

503 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

10 d

Dose descriptor:

other: LC90

Effect conc.:

1 220 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

10 d

Dose descriptor:

NOEC

Effect conc.:

126 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: from 3.7 (126 mg/kg dw) to 96.3 % (96.3 mg/kg dw)
- Mortality in control: 3.3 %

Results with reference substance (positive control):

- Results with reference substance valid
- Relevant effect levels: LC50 = 13.3 mg/kg dw

Reported statistics and error estimates:

LC50, LC10 and LC90 values calculated by using the standard procedure PROBIT analysis, National Swedish Environmental Protection Board (Version 2.3, 1990).
Calculation of NOEC by single factor ANOVA followed by Dunnett's procedure for comparing each concentation mean with the control mean.

Test acceptability:

The test acceptance criteria given were fulfilled :

- the amphipods were not held without sediment for more than 14 days before they were used for testing;

- the mortality in the individual control replicate did not exceed 40%;

- the entire batch was from the same population;

- the percentage mortality in the blank was less than 15 %;

- the oxygen contnentwas greater than 40%;

- the 10 -d LC50 for the fluoranthene was 13.3 mg/kg.

Validity criteria fulfilled:

yes

Remarks:

Amphipods held without sediment for less than14 days; Mortality in the individual blank less than 40%; All amphipods from the same population; Mortality in the blank less than 15%; 10-d LC50 of reference substance (fluoranthen) = 19.9 +/- 10.3 mg/kg sedim

Conclusions:

10-d LC50 = 503 mg/kg sediment dw
10-d NOEC = 126 mg/kg sediment dw

Executive summary:

An acute toxicity test was conducted on the marine amphipod Corophium volutator. The test substance concentrations ranged from 126 to 1495 mg/kg sediment dw. The test sediment was from the same unpolluted site as the amphipods. The seawater was natural seawater from an unpolluted site at about 80 m depth in Byfjord, filtered through sand filter at the collection. The test substance was dissolved in acetone and added to the sediment as follows: 5 mL acetone containing the test substance was added to 130 g pre-dried sediment; after the acetone had dried off in a fume cupboard, the sample was added to 510 g of damp sediment in a plastic bucket, 130 mL seawater was added to the bucket and the bucket was shaken (120 rpm) for 5 hrs. The spiked sediment was then split into three beakers, 400 mL of seawater was added to each beaker, and they were aerated overnight before the test organisms were introduced. The blanks were prepared the same way (three with and three without acetone). In the test, 4 concentrations were tested in a geometric series: 126, 308, 668 and 1495 mg/kg. Three replicates were used for each concentration and each blank.

Dissolved oxygen was > 40% during the study. The pH was 8.1. The temperature was 15 +/- 2 °C.

Test substance concentration	Initial values		Oxygen (% saturation)
	pH	O2%	5 d	10 d
Blank	8.1	95	96	96
126 mg/kg dw	8.1	95	96	90
308 mg/kg dw	8.1	95	96	93
668 mg/kg dw	8.1	95	93	88
1495 mg/kg dw	8.1	96	90	93
Reference, 5.57 mg/kg dw	8.1	95	90	96
Reference, 10.3 mg/kg dw	8.1	95	90	93
Reference, 18.9 mg/kg dw	8.1	95	93	95
Reference, 32.0 mg/kg dw	8.1	95	96	91

The test organisms (5 -10 mm) were obtained from the same unpolluted site as the sediment.

No deviation from the protocol was noted. No analytical monitoring was performed.

Results:

Concentration (mg/kg dw)	Total number of specimen per concentration	Number of specimen per vessel			Number of dead (10 days)
		A D	B E	C F	A D	B E	C F	Total
Control	60	10 10	10 10	10 10	2 0	0 0	0 0	2
126	27	9	9	9	1	0	0	1
308	27	9	9	9	3	1	2	6
668	27	9	9	9	6	5	6	17
1495	27	9	9	9	8	9	9	26
Ref., 5.57	30	10	10	10	0	0	0	0
Ref., 10.3	27	9	9	9	2	3	3	8
Ref., 18.9	27	9	9	9	8	7	6	21
Ref., 32.0	27	9	9	9	9	9	9	27

The results mean that the 10 -d LC50 is 503 mg/kg sediment dry weight as shown in the following table:

Test substance (mg/kg sediment dw)	LC10	LC50	LC90	NOEC
Fluoranthene (reference substance)	8.2	13.3	21.6	5.57
DEV 2006-16	207	503	1220	126

Description of key information

The 10d-LC₅₀ and 10d-NOEC for the marine sediment amphipod Corophium volutator were reported to be respectively 537 and 171 mg/kg sediment (dw) (geometric mean).

However, as long-term data is not available for this end-point, the environmental risk is assessed using the Petrorisk model.

Additional information

Short-term studies:

The marine amphipod Corophium volutator was exposed to sediment spiked with Hydrocarbons, C14-C18, n-alkanes, isoalkanes, cyclics, <2% aromatics for 10 days. Fourteen studies were available and give LC₅₀ values. The geometric mean of LC₅₀ is 537 mg/kg sediment (dw). In most of the studies, LC₁₀ were calculated and the geometric mean of the 12 available values is 112.6 mg/kg sediment (dw). At last, the 7 more recent studies reported NOEC values and the lowest one was 100 mg/kg (dw).

The marine mollusc bivalve Abra alba was exposed to sediment spiked with Hydrocarbons, C14-C18, n-alkanes, isoalkanes, cyclics, <2% aromatics for 5 days. Four studies were available and give LC₅₀ values. The 5-day LC₅₀ value ranged from is 36 +/- 11 to 103 +/- 22 mg test substance / kg 8% (dw) standard sediment suspension.

Long-term studies:

No data is available for long-term sediment toxicity.

In accordance with Annex IX column 2, testing does not need to be conducted as the hazard is adequately assessed by equilibrium partitioning.  Substance is a hydrocarbon UVCB: The hydrocarbon block method is used for environmental risk assessment (see REACH guidance, R7, app.13-1). PNECs for hydrocarbon blocks have been derived using aquatic PNECs and the equilibrium partitioning method (EqP) using representative structures. Justification for this approach is provided in Redman et al., 2014. Extension and validation of the target lipid model for deriving predicted no-effect concentrations for soils and sediments. ET&C, Vol. 33, No. 12, pp. 2679–2687. See Product Library tab in “assessment report. PetroRisk information excel” spreadsheet attached to Section 13 for PNEC values.

 

The aquatic PNECs have been derived using the HC5 statistical extrapolation method and the target lipid model using representative structures. Given the large database of organisms included in the target lipid model, an assessment factor of one has been applied to the HC5.