Dialkylheteromonocyclium alkanoate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Details on test solutions:

The stock solution (100 mg/L test item was weighed out) was freshly prepared with dilution water.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Test organism: Daphnia magna STRAUS (Clone 5)
Culture medium: Elendt M4, according to ELENDT (1990), modified to a total hardness of 160 to 180 mg CaCO3/L
Culture feeding: At least 5 times per week ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata, Desmodesmus
subspicatus and Chlorella vulgaris, with an algae cell density of > 10E6 cells/mL.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test conditions

Hardness:

288 mg CaCO3/L

Test temperature:

20.9 °C

pH:

7.76-7.78

Dissolved oxygen:

8.38-8.60 mg O2/L

Nominal and measured concentrations:

Nominal: 100 mg/L

Details on test conditions:

Culture: In glass vessels (2 - 3 L capacity) with approximately 1.8 L culture medium, at 20 +/- 2 °C, in an incubator, 16 h illumination, light intensity
of max. 20 µE*m-2 * s-1
Test duration: 48 h
Test vessels: Glass beakers (4 cm ID x 7 cm H), 50 mL capacity
Test volume per vessel: 20 mL
Dilution water: ISO Test water, according to OECD 202, Annex 3
Number of daphnids and replicates: 20 daphnids, divided into 4 replicates, each with 5 daphnids per limit concentration solution and control
Age of daphnids at experimental starting: 2 to 24 h old daphnids were used for the study. They were obtained by removing the mother animals twice
within 22 h.
Acclimatization: At least 2 h in dilution water
Application: Per replicate, 20 g test solution was weighed out into the test vessels. This corresponds to 20 mL per test vessel. The daphnids were
inserted with a small amount of dilution water by a pipette.
Test temperature: 18 - 22 °C, ± 1 °C constant
Illumination/Photoperiod: Diffuse light, light intensity max. 20 µE*m-2 * s-1 / 16/8 h light/dark cycle
Feeding: The daphnids were not fed during the study.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC10

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:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

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 5

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

The percentage immobility for the reference item was determined after 24 h. The EC50-value with 95 % confidence interval (CI) was calculated by
sigmoidal dose-response regression. The EC50-value for the most recent of the monthly performed reference tests was:
EC50: 1.74 mg/L (CI 1.49 - 2.00 mg/L)
The EC50-value of the reference item potassium dichromate after 24 h is within the prescribed concentration range of 1.0 - 2.5 mg/L of quality
criteria according to AQS P 9/2 (05/1996) for daphnids clone 5 cultured in Elendt M4 medium. The EC50-value of the reference item is also within therecommended range of 0.6 - 2.1 mg/L according to OECD-Guideline 202.

Reported statistics and error estimates:

EC10 / 50 /100-values after 24 and 48 h and the NOEC and LOEC after 48 h were estimated directly from the observation data, without mathematical calculation.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

At the limit concentration of 100 mg/L of the test item 1,3-Dimethyl-1H-imidazol-3-iumpropanoate, no effect was observed on Daphnia magna.