2,2'-azobis[2-methylpropionamidine] dihydrochloride

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:

12 November 1996 - 13 December 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

check conclusions for more details

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: direct dispersion in water
- Differential loading: 2.0; 3.6; 6.4; 11.2 and 20.0 g of test material were each separately dispersed in 150 ml of reverse osmosis water prior to dispersal in dechlorinated tap water. The volume was adjusted to 20 L to give the test series of 100; 180; 320; 560 and 1000 mg/L.
- Evidence of undissolved material (e.g. precipitate, surface film, etc): not mentioned

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Golden orfe
- Strain: Leuciscus idus
- Source: New Xotic Fish Centre, Alfreton, Derbyshire, U.K.
- Age at study initiation: juvenile
- Feeding during test: no

ACCLIMATION
- Acclimation period: 2 - 9 December 1996
- Acclimation conditions (same as test or not): yes
- Type and amount of food: Tetramin flake food
- Feeding frequency: no data. the food was discontinued 48 h prior to the start of the study.
- Health during acclimation (any mortality observed): no

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Post exposure observation period:

no

Hardness:

100 mg/L CaCO3

Test temperature:

21 ± 1 C

pH:

7.3-7.7

Dissolved oxygen:

7.3 - 8.4 mg/L

Nominal and measured concentrations:

Nominal: 100, 180, 320, 560 and 1000 mg/L
Measured: not performed

Details on test conditions:

TEST SYSTEM

- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: glass, 20 L
- Aeration: yes
- Renewal rate of test solution (frequency/flow rate): daily
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 0
- Biomass loading rate: 0.68 g bodyweight/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: laboratory tap water dechlorinated through an activated carbon filter
- Total organic carbon: 2.3 mg/L
- Particulate matter: no data
- Metals: all ≤ 100 µg/L
- Pesticides:
- Chlorine: 0.17 mg/L
- Alkalinity: 137 mg/L
- Ca/mg ratio: ca. 6:1
- Conductivity: 627 µS/sm
- Culture medium different from test medium: no
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light and 8 h darkness
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : cumulative mortality and sublethal effect recorded at 3, 6, 24, 48, 72 and 95 h

TEST CONCENTRATIONS

- Range finding study: yes
- Test concentrations: 1.0; 10; 100 and 1000 mg/L
- Results used to determine the conditions for the definitive study: no mortalities at 1.0, 10 and 100 mg/L after 96h exposure. At 1000 mg/L no mortalities were observed until 48 h exposure and 100% mortality was recorded at 96 h exposure.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

570 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 470-680 mg/L

Details on results:

- Behavioural abnormalities: yes swimming at the surface and moribund fish at 560 mg/L and above.
- Observations on body length and weight: mean body weight and length at the end of the study 1.36 g (s.d. = 0.24) and 5.0 cm (s.d. = 0.1)
- Other biological observations: no
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no

Validity criteria fulfilled:

no

Remarks:

no analytical evidence that the concentration of the substance has been maintained during the study.

Conclusions:

Based on the report, the acute toxicity of V-50 to the freshwater fish golden orfe (Leuciscus idus) has been investigated according to the OECD 203. Under the current test conditions the 96 h LC50 is 570 mg/L with 95% confidence limits of 470 - 680 mg/L.
Although substance concentration was not analytically monitored throughout the testing period stability of substance of more than 80 % of nominal concentration is assumed. Based on available information on stability of the substance a half-life of about 60 hours is estimated. Since daily renewal of test solution observance of 80 % criteria is most likely. Additionally, this assumption is supported by analytical data from semi-static test with Daphnids which was conducted at similar conditions.

Description of key information

Key value is based on observations in semi-static testing with Leuciscus idus.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

570 mg/L

Additional information

Although key study cannot be validated unequivocally due to missing analytical monitoring of the concentration of the test substance the study is considered to be reliable with restrictions. With view to all available information on substance stability observance of the 80 % criteria of test concentrations is assumed in semi-static study design with daily renewal of the test solution.