Rape oil, oxidized

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 March 2010 to 12 March 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study has been performed according to OECD and/or EC guidelines and according to GLP principles.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Guidance document on aquatic toxicity testing of difficult sunstances and mixtures, OECD series on testing and assesment number 23, December 14, 2000.

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

During the test singular samples for TOC-analysis were taken from the WAF prepared at a loading rate of 100 mg/l and the untreated control according to the schedule below.

Frequency at t=0 h and t=48 h
Volume 40 ml
Storage Samples were stored in a refrigerator until analysis.

Vehicle:

no

Details on test solutions:

The batch of Blown rapeseed oil tested was a yellow/brown viscous liquid with a purity indicated as 100% and not completely soluble in test medium at the concentrations tested.

Preparation of the test solutions started with loading rates prepared individually at 1.0, 10 and 100 mg/l applying 48 hours of magnetic stirring to achieve maximum dissolution in test medium. The magnetic stirring was followed by a settlement period of 2 hours. This resulted in clear and colourless to slightly hazy solutions with a floating layer. The Water Accommodated Fractions (WAFs) were then collected by siphoning the water phase. The WAFs of 1.0 and 10 mg/l were all clear and colourless, while the WAF prepared at 100 mg/l was slightly hazy.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: Daphnia magna (Crustacea, Cladocera) (Straus, 1820)
- Source: In-house laboratory culture with a known history.
- Age at study initiation: < 24 hours
- Method of breeding: With newborn daphnids, i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass culture vessel.
- Feeding during test: No

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

180 mg/l expressed as CaCO3

Test temperature:

between 19.6 and 20.4°C

pH:

7.9

Dissolved oxygen:

between 9.0 and 9.5

Nominal and measured concentrations:

Nominal concentrations: control and 100 mg/L
Measured concentrations: Analyses were based on Total Organic Carbon (TOC) contents. The TOC concentrations measured in the treated samples were only slightly exceeding those measured in the control samples, indicating that the actual test substance concentration was very low. The actual measured concentration was at approximately 1.0 to 1.5 mg C/l when corrected for the carbon measured in the control samples. The TOC content of Blown rapeseed oil was determined to be 74.01% (based on NOTOX Project 493030). Thus, the actual Blown rapeseed oil concentration in solution was between approximately 1.4 and 2.0 mg/l.
The low exposure concentration was not unexpected considering the poor solubility of Blown rapeseed oil and the observed undissolved test substance that was present as a floating layer in the dispersion after stirring and which was removed when collecting the water phase for testing.

Details on test conditions:

- Type: open
- Material, size, headspace, fill volume: glass, 100 ml, normal headspace, 80 ml
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4 for the highest concentration and 2 for the lower concentrations
- No. of vessels per control (replicates): 4
TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Adjusted ISO medium: the following chemicals (analytical grade) are dissolved in tap water purified by Reverse Osmosis (RO-water, GEON Waterbehandeling, Berkel-Enschot, The Netherlands):
Macro salts:
CaCl2.2H2O : 211.5 mg/l
MgSO4.7H2O: 88.8 mg/l
NaHCO3 : 46.7 mg/l
KCl : 4.2 mg/l
The hardness: 180 mg/l expressed as CaCO3 and the pH: 7.7 ± 0.3 after aeration.
- Culture medium different from test medium: yes, for culturing M7 medium is used
OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours photoperiod daily
EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : EC50 t=24, 48 h and NOEC
TEST CONCENTRATIONS
- Spacing factor for test concentrations: 10
- Test concentrations: control and 1.0, 10, 100 mg/l

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7,)

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 other: mg/l (WAF prepared at a loading rate of 100 mg/l)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: mg/l (WAF prepared at a loading rate of 100 mg/l)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: mg/l (WAF preared at a loading rate of 100 mg/l)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Behavioural abnormalities: no
- Immobility of control: no immobility was observed.
- Other adverse effects control: no

Results with reference substance (positive control):

The 24h-EC50 was 0.75 mg/l with a 95% confidence interval between 0.56 and 1.0 mg/l.
The 48h-EC50 was 0.36 mg/l with a 95% confidence interval between 0.28 and 0.49 mg/l.

Reported statistics and error estimates:

No EC50 could be calculated because the test substance proved to be non-toxic (EC50 > maximum soluble concentration).

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the present study Blown rapeseed oil did not induce significant acute immobilisation of Daphnia magna when exposed to a WAF prepared at a loading rate of 100 mg/l after 48 hours of exposure (NOEC). The 48h-EC50 exceeded a WAF prepared at a loading rate of 100 mg/l, which can be considered to represent the maximum soluble concentration in test medium. TOC-analyses showed that the actual concentration in solution was between approximately 1.4 and 2.0 mg/l.

Description of key information

48h-EL50: > 100 mg/L  (study in accordance with OECD 202)

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

For Rape oil, oxidized a study was conducted according to OECD guideline 202 under GLP. The 48h-NOEL and 48h-EL50 were found to be 100 and > 100 mg/l respectively.