Oct-2-ene

Sediment toxicity

Link to relevant study record(s)

Reference

Endpoint:

sediment toxicity: short-term

Type of information:

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

Adequacy of study:

key study

Study period:

14 August to 8 December 1995

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP, guideline, available as unpublished report, notable limitations in reporting

Justification for type of information:

Read-across between the target substance Oct-2-ene (EC 203-894-2 / CAS 111-67-1) and source substance 1-Tetradecene (EC 214-306-9/ CAS 1120-36-1) is based upon the similarity of the chemical structures and their respective physico-chemical properties. The ECHA Read-Across Assessment Framework (RAAF) states that substances with qualitatively similar properties can form the basis of read-across in circumstances where the source and target substances share such similar characteristics.
Target substance Oct-2-ene and source substance 1-Tetradecene are each mono-constituent linear olefins. Structurally, the differences between source and target substances include: 1) the length of the carbon chain (eight for the target substance, and fourteen for the source substance); and 2) the location of the carbon-carbon double bond (uniformly at the C2 position for the target substance, but uniformly at the C1 terminal position for the source substance).
The target and source substances both fit within the boundaries of chemical category of higher olefins. Studies conducted by the HOPA consortium on a large range of higher olefin category members (including 1-Tetradecene) demonstrated sufficiently similar physico-chemical, environmental fate and toxicological properties to substantiate the basis for read-across; although category members of a carbon chain length C10 or greater may exhibit a reduced acute aquatic toxicity attributable to reduced water solubility, the environmental toxicity of all category member is expected to be manifested as non-polar narcosis. In addition, both 1-Tetradecene and Oct-2-ene are expected to exhibit sufficient adsorption to soil and sediment to exhibit similar long-term toxicity; therefore, read-across with respect to sediment and terrestrial toxicity endpoints is appropriate. Justification for inclusion of Oct-2-ene within the boundaries of the higher olefins category, and the relevance of each category member as an analogue substance to Oct-2-ene, is provided in Section 13 (Document name: “HOPA Higher Olefins CJD with Category Matrix Report [rev 1 Sept 2016]”; Document name: "ACC Product Stewardship Summary for Higher Olefins Category (2008-12-03)”).

Reason / purpose for cross-reference:

read-across source

Principles of method if other than guideline:

conducted in accordance with PARCOM guidelines.

GLP compliance:

yes

Remarks:

No certificate

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No data reported

Analytical monitoring:

no

Details on sampling:

At the beginning, middle and end of the test the aeration system was removed and conductivity, pH, dissolved oxygen and temperatures were recorded. At the same time the number of animals on the sediment surface and any other additional information was recorded.

Vehicle:

yes

Details on sediment and application:

Collected from a point adjacent to the site of Corophium collection.

Test organisms (species):

Corophium volutator

Details on test organisms:

Obtained from Sebay, Mainland Orkney.

Study type:

laboratory study

Test type:

static

Water media type:

saltwater

Type of sediment:

natural sediment

Duration:

10 d

Exposure phase:

total exposure duration

Post exposure observation period:

none

Hardness:

No data reported

Test temperature:

14.3-15.9°C

pH:

7.84-8.22

Dissolved oxygen:

83-98%

Salinity:

35‰

Ammonia:

No data reported

Nominal and measured concentrations:

Nominal concentrations of 13.46,128.62,1292.25, 4066.24 and 12397.57 mg/kg were pepared. (Calculated as mg/kg dry sediment, from the wet weight of sediment used and a wet:dry weight ratio of 1.36)

Details on test conditions:

The sediment was homogenised. Approx 20g of wet sediment was placed in a tared glass crystallising dish and weighed to ±0.01g. The dish and sediment were placed in a drying oven at approx 60°C for a minimum of 24h. After drying, the dish was re-weighed. The ratio of wet weight to dry weight was used to convert nominal exposure concentrations on a wet weight basis to nominal exposure concentrations on a dry weight basis. The test was conducted in 1-litre tall-form borosilicate glass beakers, each containing approximately 150ml (2cm depth) of sediment and 850ml filtered seawater. Replication = 3 per treatment. 5 controls. 20 organisms per replicate, 60 organisms per concentration. Test conducted under constant dim illumination. Conductivity 50.5-63.9 mS

Key result

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

86.95 other: mg/kg

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 61.29-126.55

Details on results:

The number of animals responding after 10 days in each replicate was expresses as a proportion of the number exposed. The proportaion data were arcsin transformed, and the three replicate transformed values were averaged. The average values were back-transformed and an LC50 calculated from teh resulting proportion data using the moving average-angle method.

Results with reference substance (positive control):

No data reported

Reported statistics and error estimates:

Control mortality was 7% over the duration of the test.

Validity criteria fulfilled:

not specified

Remarks:

Insufficient data

Conclusions:

The 10 day LC50 for Corophium volutator was 86.95 mg/kg dry weight.

Executive summary:

The 10 day LC50 for Corophium volutator was 86.95 mg/kg dry weight. This GLP study followed a standard guideline. No detail on the composition of the sediment is reported, and analytical monitoring was not included.This result gives an indication of the levels of 1-tetradecene that may cause sediment toxicity.

Description of key information

The key study was a static 10-d toxicity test on the effects of an analog substance on the marine amphipod, Corophium volutator following an OSPAR PARCOM guideline (Roddie, 1997). The 10-d LC50 was reported as 86.95 mg/kg d.w based on nominal concentrations. 

Key value for chemical safety assessment

EC50 or LC50 for marine water sediment:

86.95 mg/kg sediment dw