DCHA-isostearate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19.11.2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

Accordint to OECD 202 resp. EU C.2

GLP compliance:

yes (incl. QA statement)

Test material

Reference

Name:

Unnamed

Type:

Constituent

Specific details on test material used for the study:

The water-accommodated fraction was prepared by weighing of the nominal load, adding the corresponding amount of dilution water and shaking vigorously for 24 hours. The resulting solution was filtrated through 0.45 µm filters

Sampling and analysis

Analytical monitoring:

not specified

Test solutions

Details on test solutions:

Sample Preparation: 25 ml filtrated solution was filled up to 100 ml. After addition of 1 ml 2m NaOH and 7 g NaCl, the solution was extracted twice with iso-hexane (4 ml and 3 ml). The organic phase was dried with Na2SO4 and transferred in a 10 ml volumetric flask. Then 1 ml ISTD Diphenylamine (1000 mg/l in iso-hexane) was added and the volumetric flask was filled up with iso-Hexane.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna
Variety: STRAUS
Strain: Berlin
Sex: female
Age: between 0 and 24 hours
Origin: Umweltbundesamt Berlin
Arrival of Strain: 27. Sep. 2007
Selection of the test system was made following the proposal af the guidelines.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

The test vessels were left to stand for 48 hours. After 24 and 48 hours, the immobilised daphnia were counted. Daphnia are considered immobilised if they perform no movements or are only able to move their antennae when the beaker is gently agitated.

Test conditions

Test temperature:

19.7 - 20.6 °C

pH:

7.7 - 8.0

Dissolved oxygen:

The concentration of dissolved oxygen stayed above 7.9 mg/L throughout the test.

Nominal and measured concentrations:

Nominal Conc. 100 mg/L
Measured Conc. 0h: 99.6 mg/L
Measured Conc 48h: 93.2 mg/L

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7 was used as positive control. the 24h-EC50i of potassium dichromate was determined as 1.7 mg/L, lying within the demanded range of 0.6 - 1.7 mg/L.

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The main study was performed using one concentration containing 100 mg/L. Twenty daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised daphnia were counted.
The concentration showed no toxicity. None of the animals were immobilised in the control.
The 24h-EC50i of potassium dichromate was tested in a current positive control test. The value was determined as 1.7 mg/L, lying within the demanded range of 0.6 - 1.7 mg/L.
At the beginning and at the end of the test, the content of the test item in the test solutions was determined by measurement of Dicyclohexylamine after saponification via GC. The recovery after 48 hours was 94% of the start concentration, the correlation between nominal and measured concentration was very good. Therefore, the determination of the biological results was based on the nominal concentration.
The following results were determined for the test item Dicyclohexylammonium Isostearat (species: Daphnia magna).
24h-NOEC = 100 mg/L
48h-NOEC = 100 mg/L
24h-EC50i > 100 mg/L
48h-EC50i > 100 mg/L

Executive summary:

The following results were determined for the test item Dicyclohexylammonium Isostearat (species: Daphnia magna).

24h-NOEC = 100 mg/L

48h-NOEC = 100 mg/L

24h-EC50i > 100 mg/L

48h-EC50i > 100 mg/L