2,2'-azobis[4-methoxy-2,4-dimethylvaleronitrile]

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08.09.17-15.09.17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name:
- Strain: Danio rerio HAMILTON-BUCHANAN
- Source: Dehner Garten Center, 67433 Neustadt
- Age at study initiation (mean and range, SD):
- Length at study initiation (length definition, mean, range and SD): 2 ± 1 cm
- Weight at study initiation (mean and range, SD):
- Method of breeding:
- Maintenance of the brood fish:

ACCLIMATION
- Acclimation period: Before being used for the test, the fish were kept for at least 12 days under test conditions. During 7 days, no mortality occurred.
- Acclimation conditions (same as test or not):
- Type and amount of food during acclimation:
- Feeding frequency during acclimation:
- Health during acclimation (any mortality observed):

QUARANTINE (wild caught)
- Duration:
- Health/mortality:

FEEDING DURING TEST
- Food type: warmwater fishfood
- Amount:
- Frequency: 3 times per day

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

0.71 mmol

Test temperature:

22.8 – 23.3 °C

pH:

8.26

Dissolved oxygen:

7.0-8.8 mg/L (> 85 %)

Conductivity:

174 µS/cm (@25 °C)

Nominal and measured concentrations:

nominal: 100 mg/L
measured: 94 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass aquaria
- Type (delete if not applicable): -
- Material, size, headspace, fill volume: glass aquaria, maximal volume 10 L, fill volume: 7 L
- Aeration: accomplished with glass tubes
- Type of flow-through (e.g. peristaltic or proportional diluter): -
- Renewal rate of test solution (frequency/flow rate): -
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): -
- Biomass loading rate: 1 fish/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
- Total organic carbon: 0.6 mg/L
- Particulate matter:
- Metals:
- Pesticides: < LOD
- Chlorine:
- Alkalinity:
- Ca/mg ratio: 12:1
- Culture medium different from test medium:
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: 12/12
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Validity criteria fulfilled:

yes

Conclusions:

No mortality was observed during the test. Therefore, the threshold is stated > 100 mg/L.

Executive summary:

One valid experiment was performed.

The toxicity against Danio reriowas tested using a static test design.

 

The study was performed using one concentration containing 100 mg/L. The blank control and the concentration showed no mortality.

At the start and at the end of the test, the content of the test item in the test solutions was determined using HPLC.

The measured concentration at the beginning was not plausible. This was caused very likely by an error during sample preparation. Because the values looked plausible at first, the sample was not measured again. Therefore, the measured start concentration was not used for evaluation.

This can be stated as uncritical for the outcome of the study because the measured concentration at the end of the test was 93.8 % of the nominal concentrations. Therefore, the determination of the results was based on the nominal concentration.

 

The following results for the test item 2,2'-Azobis (4-methoxy-2,4-dimethyl valeronitrile) could be determined:

 

96h-NOEC ≥ 100 mg/L
96h-LOEC > 100 mg/L
96h-LC50 > 100 mg/L

Description of key information

No mortality is observed in an OECD 203 guideline study. The highest concentration is used as key value.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

100 mg/L