Semicarbazide hydrochloride

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Remarks:

The 96-hour acute toxicity in zebrafish was recorded as a precursor to a longer study measuring estrogenic effects. The acute toxicity determination makes reference to an appropriate US EPA test method and overall the test methodology is comparable to current OECD guideline methods. There is no clear indication of analytical verification of test concentrations in relation to the acute toxicity test (although details of analytical monitoring are provided in relation to the main test). The published data makes no clear indication of GLP compliance.

Qualifier:

according to guideline

Guideline:

EPA OTS 797.1400 (Fish Acute Toxicity Test)

Version / remarks:

Reported as "Fish Acute Toxicity Test (USEPA 1996)"

Deviations:

not specified

GLP compliance:

not specified

Remarks:

The data is taken from a publication and makes no explicit reference to GLP compliance. Note that in the absence of a claim of GLP compliance a reliability (Klimisch) score of 2 has been assigned (refer above for additional details)

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- Age at study initiation: Adult
- Length at study initiation: 3.76 ± 0.12 cm
- Weight at study initiation: 0.58 ± 0.04 g

ACCLIMATION
- Acclimation period: 2 Weeks
- Acclimation conditions: Same as test
- Type and amount of food during acclimation: Brine shrimp
- Feeding frequency during acclimation: Twice daily

FEEDING DURING TEST
- No food was supplied from 24 hours before the start of the test, or during the test period

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Test temperature:

26 ± 1°C

pH:

7.2 - 7.6

Dissolved oxygen:

7.0±0.1 mg/L

Nominal and measured concentrations:

Nominal: 0 (control), 23.0, 25.3, 27.8, 30.6 and 33.7 mg/L.

Details on test conditions:

TEST SYSTEM
- Test vessel: 5 L glass tanks
- Renewal period of test solution: 24 hours
- No. of organisms per vessel: 10
- No. of vessels per concentration: 2 (test was performed in duplicate)
- No. of vessels per control: 2

TEST MEDIUM / WATER PARAMETERS
Dechlorinated tap water

OTHER TEST CONDITIONS
- Photoperiod: 14 hours light / 10 hours dark

EFFECT PARAMETERS MEASURED: Mortality (number of dead fish), recorded every 24 hours

TEST CONCENTRATIONS
- Determined based on a pre-test (details not specified)

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

26.29 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% confidence limits:

Remarks:

24.42 - 27.78 mg/L

Details on results:

- Behavioural abnormalities: Compared to the controls which showed no behavioural anomalies, some of the treated fish showed erratic swimming or loss of equilibrium prior to death.

Hyperaemia in the pharynx was observed in most of the dead fish.

Validity criteria fulfilled:

not specified

Conclusions:

The 96 hour LC50 of semicarbazide in zebrafish was calculated to be 26.29 mg/L (95% confidence limits 24.42 - 27.78 mg/L).

Description of key information

The 96 hour LC₅₀ of semicarbazide in zebrafish was calculated to be 26.29 mg/L (95% confidence limits 24.42 - 27.78 mg/L).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

26.29 mg/L