Anthranilamide

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:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Identification:
Anthranilamide
Physical state/Appearance:
Beige powder
Purity:
99.65%
Storage Conditions:
Room temperature in the dark

Analytical monitoring:

yes

Details on sampling:

The samples were prior analysis

Vehicle:

no

Details on test solutions:

A nominal amount of test item (200 mg) was dissolved in test water and the volume adjusted to 2 liters to give the 100 mg/L test concentration from which a series of dilutions was made to give further test concentrations of 10, 18, 32 and 56 mg/L.
Each prepared concentration was inverted several times to ensure adequate mixing and homogeneity.

Test organisms (species):

Daphnia magna

Details on test organisms:

The test was carried out using 1st instar Daphnia magna derived from in-house laboratory cultures.
Adult daphnia were maintained in 150 mL glass beakers containing Elendt M7 medium (see Annex 2) in a temperature controlled room maintaining the water temperature at 18 to 22 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that the young daphnids produced overnight were less than 24 hours old. These young were removed from the cultures and used for testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Test type:

static

Water media type:

freshwater

Remarks:

reconstituted water (ISO medium)

Limit test:

no

Total exposure duration:

48 h

Test temperature:

Temperature was maintained at 21 °C to 22 °C throughout the test

pH:

48 hours
Control: 7.6
10mg/L: 7.7
18mg/L: 7.7
32 mg/L: 7.7
56mg/L: 7.8
100 mg/L: 7.8

There were no treatment related differences for pH

Dissolved oxygen:

48 hours
Control: 9.0 mg O2/L
10mg/L: 8.9 mg O2/L
18mg/L: 8.9 mg O2/L
32 mg/L: 8.9 mg O2/L
56mg/L: 8.9 mg O2/L
100 mg/L: 8.8 mg O2/L

There were no treatment related differences for oxygen concentration

Nominal and measured concentrations:

Based on the results of the range-finding test the following test concentrations were assigned to the definitive test: 10, 18, 32, 56 and 100 mg/L.

Details on test conditions:

In the definitive test 150 mL glass beakers containing approximately 100 mL of test preparation were used. At the start of the test 5 daphnids were placed in each test and control vessel at random, in the test preparations. Four replicate test and control vessels were prepared. The test vessels were then covered to reduce evaporation and maintained in a temperature controlled room maintaining the water temperature at 18 to 22 °C with a maximum deviation of ±1 °C with a photoperiod of 16 hours light (between 200 and 1200 Lux) and 8 hours darkness with 20 minute dawn and dusk transition periods. The daphnids were not individually identified, received no food during exposure and the test vessels were not aerated.
The control group was maintained under identical conditions but not exposed to the test item.
The test preparations were not renewed during the exposure period.

Test Organism Observations
Any immobilization or adverse reactions to exposure were recorded at 24 and 48 hours after the start of exposure. The criterion of effect used was that daphnia were considered to be immobilized if they were unable to swim within 15 seconds after gentle agitation.

Reference substance (positive control):

yes

Remarks:

A positive control used potassium dichromate as the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L.

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

24 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

84 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Verification of Test Concentrations
Analysis of the test preparations at 0 and 48 hours (see Annex 5) showed measured test concentrations to range from 93% to 113% of nominal concentrations and so the results are based on nominal test concentrations only.

Immobilization Data
Analysis of the immobilization data by Probit analysis using Linear Maximum-Likelihood regression nominal test concentrations gave the following results:
Time (h) EC50 (mg/L) 95% Confidence limits (mg/L)
24 84 Not possible to determine
48 24 22 - 26
The No Observed Effect Concentration after 24 and 48 hours exposure was 18 mg/L. The Lowest Observed Effect Concentration was 32 mg/L.
The slopes and their standard errors of the response curves at 24 and 48 hours were 1.6 (SE = 0.12) and 13 (SE = 0.019) respectively.

Sub-Lethal Effects
No sub-lethal effects of exposure were observed throughout the test.

Positive control

A positive control (Envigo Study Number MS29MC) used potassium dichromate as the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L.

Exposure conditions for the positive control were similar to those in the definitive test.

Analysis of the immobilization data by the probit analysis using the linear maximum likelihood regression method at 24 and 48 hours using the ToxRat Professional computer software package based on the nominal test concentrations gave the following results:

Time Point (hours)	EC50(mg/L)	95% Confidence Limits (mg/L)	No Observed Effect Concentration (NOEC) (mg/L)	Lowest Observed Effect Concentration (LOEC) (mg/L)
24	0.83	0.7 - 0.98	0.56	1
48	0.64	Not possible to determine	0.56	1

The No Observed Effect Concentration is based upon equal to or less than 10% immobilization at this concentration.

The results from the positive control with potassium dichromate were within the normal range for this reference item.

Validity criteria fulfilled:

yes

Conclusions:

Exposure of freshwater invertebrate Daphnia magna to the test item has been investigated and gave the following results:

EC50 (mg/L): 24
95% Confidence Limits (mg/L) 22 - 26
No Observed Effect Concentration (NOEC) (mg/L): 18
Lowest Observed Effect Concentration (LOEC) (mg/L): 32

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

24 mg/L