Fatty acids, tall-oil, reaction products with pentaethylenehexamine

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:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study according to GLP.

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

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Analytical determinations of the test substance concentrations were based on dissolved organic carbon (DOC). Determinations were conducted in the definitive test at the beginning and after 24 and 48 h of exposure. Each replicate was measured individually.

Vehicle:

no

Details on test solutions:

Since the test substance is a multi-component substance that is only partially soluble, the water accommodated fraction (WAF) approach was used. The loading levels of the test material were prepared by adding the respective amount of an acetonic stock solution to an empty glass vessel. After complete evaporation of the solvent, the aerated Daphnia medium was added, moderately stirred for a minimum of 24 h, followed by filtration (MILLIPORE AP15 glass fiber filter). The resulting water soluble fractions (WSF) were used in the test. The preparation of the water soluble fraction was based on the results of the non-GLP solubility test series.

Test organisms (species):

Daphnia magna

Details on test organisms:

Test organism: Daphnia magna (Straus, 1820)
Breeding: Parental and young Daphnia held in 4 l glass aquaria (3 l medium) at 20 ± 2 °C
Illumination: 16 h per day
Medium: Continuously aerated Elendt M4 medium; prepared with deionised water (conductivity <1.5 µS/cm)
Feed: Suspension of Desmodesmus subspicatus in Elendt M4 medium with an optical density OD680 of about 15 units
Frequency of feeding: 400 μl per Daphnia per day, except on weekends
Control of sensitivity: Acute reference test with potassium dichromate conducted twice a year

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

total hardness (as sum of Ca and Mg): 2.52 mmol/l
carbonate hardness: 0.32 mmol/l

Test temperature:

20 ± 2 °C

pH:

control: 6.9 - 7.1
exposure groups: 7.0 - 8.1

Dissolved oxygen:

control: 6.2
exposure groups: 5.7 - 6.0

Nominal and measured concentrations:

Based on the results of the range finding test, the definitive test was performed at the following loading rates: 0.625, 1.25, 2.50, 5 and 10.0 mg/l.

Details on test conditions:

Test vessel: 100 ml flasks, all-glass, with 50 ml of test medium
Test medium: Elendt M4 medium; prepared with deionised water (conductivity <1.5 µS/cm)
Number of Daphnia: 40 individuals per test concentration, 20 per vessel
Age: Less than 24 h
Light: 16 h photoperiod a day, supplied by overhead white fluorescent tubes
Temperature (target): 20 ± 2 °C (temperature-controlled room)
Test type: Static exposure conditions
Test duration: 48 h

For each test series, the following number of test flasks was used:
• Test suspension (Tn); containing test medium, test substance, two replicate samples with 20 Daphnia each
• Blank control (Bn); containing test medium, three replicate samples with 20 Daphnia each

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

2.59 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

other: EC20

Effect conc.:

2.84 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

3.31 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

DOC analyses of the test substance concentrations were conducted at the beginning, after 24 and 48 h of exposure. Net DOC concentrations (DOC concentrations after subtraction of the blank) at the beginning of the exposure were 1.57, 0.65, 1.58, 1.64 and 4.63 mg C/l. With respect to a TOC content of 75.6%, these concentrations correspond to 2.07, 0.86, 2.08, 2.16, 6.12 mg/lof the test substance, respectively. The analyses confirmed the low solubility of the test substance. The concentrations decreased below quantification limit (LOQ=0.5 mg C/l) during the exposure time. For this reason, the evaluation was based on the loading rates of the test item.

Validity criteria fulfilled:

yes

Description of key information

Acutely toxic for aquatic invertebrates. 

Additional information

Short-term toxicity to aquatic invertebrates was assessed in an OECD 202 guideline study according to GLP. Due to the results of a range finding study the concentrations in the definite test were 0.625, 1.25, 2.5, 5.00 and 10 mg/L. The results are based on the loading rates due to the uvcb character of the test substance. After 48 h of exposure, the medium effect concentration (EC50) for the test substance was calculated to be 3.31 mg/L with respect to the loading rates. The low effect concentrations, EC10 and EC20, were calculated to be 2.59 mg/L and 2.84 mg/L, respectively.