Fatty acids, rape-oil, Me esters

Sediment toxicity

Administrative data

Endpoint:

sediment toxicity: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OSP ARCOM guidelines adopted in 1995

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, rape-oil, Me esters

EC Number:

287-828-8

EC Name:

Fatty acids, rape-oil, Me esters

Cas Number:

85586-25-0

Molecular formula:

Unspecified

IUPAC Name:

methyl (11Z)-icos-11-enoate; methyl (13Z)-docos-13-enoate; methyl (9E)-octadec-9-enoate; methyl (9Z,12Z)-octadeca-9,12-dienoate

Details on test material:

- Name of test material (as cited in study report): rapeseed oil fatty acid methyl ester
- Physical state: yellowish liquid
- Analytical purity: 100% AM

Sampling and analysis

Analytical monitoring:

no

Test substrate

Vehicle:

no

Details on sediment and application:

Sediment for use in toxicity testing is collected from a point adjacent to the site of Corophium collection. On return to the Iaboratory, the sediment is wet-sieved through 0.6 mm mesh to remove larger infaunal organisms and Corophium within the test size range, and allowed to settle in tall polyethylene containers. After settling, the supernatant water is decanted and the sediment stored in a room at approximately 4 °C,
until required for testing. Immediately before the initiation of the test, the sediment is thoroughly homogenised and a representative sample taken for wet and dry weight determination. The ratio of wet weight to dry weight is subsequently used to convert nominal exposure concentrations on a wet weight basis to nominal exposure concentrations on a dry weight basis.

Test organisms

Test organisms (species):

Corophium volutator

Details on test organisms:

Organisms are collected from a site in the Bay of Suckquoy, near Sebay farm in Orkney. Specimens are gently sieved from their native sediment and held in plastic containers (approximately 51 capacity) containing some ambient water, with a small amount of detritus, until transfer to the laboratory. On return to the laboratory, the Corophium are transferred in ambient water to polythene tanks of approximately 200 litre capacity, gentle aeration is supplied. The tanks are located in a controlled-temperature room at approximately 15 °C. The stock animals are gradually acclimated from the ambient salinity of less than 5‰ tothat of undiluted seawater (approximately 35‰) in increments of approximately 10‰ per day. Once acclimation is complete, the stock tanks are maintained under semi-static conditions until the initiation of the test. The holding period in the Iabaratory is between 3 and 14 days. Sufficient detrital material is retained in each tank to provide food and some bottarn cover, but not of a density that prevents daily observation of mortality and morbidity. Dead or impaired animals are removed when observed. Specimens of approximately 5 mm in body length (excluding rostrum) are used in the toxicity tests.

Study design

Study type:

laboratory study

Test type:

static

Water media type:

saltwater

Type of sediment:

natural sediment

Limit test:

no

Exposure duration

Duration:

10 d

Exposure phase:

total exposure duration

Test conditions

Test temperature:

14.7-16.4 °C

pH:

7.91 - 8.35

Dissolved oxygen:

92 - 98% saturation

Salinity:

35 ‰

Nominal and measured concentrations:

Nominal: 10, 100, 320, 1000 and 10000 mg/kg ww
Nominal: 17.38, 174.09, 552.87, 1707.82 and 16011.13 mg/kg dw

Details on test conditions:

Tests are conducted in 1 litre capacity glass beakers each containing 2 cm depth (approximately 150 ml) of amended sediment and 850 ml of overlying seawater (1 µm filtered ultra violet treated seawater). Test beakers are maintained under constant dim illumination in a controlled temperature room for a test period of 10 days. Three replicates are prepared for each test concentration; controls are replicated five times. The beakers are assigned positions within the test area, arranged in rows of three to five and spaced to maintain effective separation of different treatments. Each row is covered with a reetangular sheet of perspex perforated with a small hole above the centre of each beaker. Aeration is provided and a stream of air bubbles are released at a depth of approximately 6 cm. Twenty animals are added to a 100 rml beaker and the contents are then dispensed into a test vessel, one beaker per vessel. Sixty organisms are exposed in total per concentration and one hundred in five vessels for controls. The finallevel of water in each test vessel is marked with a permanent marker. At the end of the test period, the contents of each beaker are gently sieved through a 0.6 mm mesh, and all surviving animals separated and counted. Missing animals are counted as dead; early mortalities will either have been consumed by survivors or have decomposed during the test period.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Duration:

10 d

Dose descriptor:

LC50

Effect conc.:

3 367.41 mg/kg sediment dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The test substance exhibited a 10d-LC50 value of 3367.41 mg/kg dw to the marine amphipod Corophium volutator in the sediment phase.