Barbituric acid

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Remarks:

According to national standard; guideline of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: According to guideline of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany (1984)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Barbituric acid

EC Number:

200-658-0

EC Name:

Barbituric acid

Cas Number:

67-52-7

Molecular formula:

C4H4N2O3

IUPAC Name:

pyrimidine-2,4,6(1H,3H,5H)-trione

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

samples were taken at 0, 24, 48, 72 and 96 hours respectively.

Test solutions

Details on test solutions:

PREPARATION OF TEST SOLUTION
weighed substance was stirred for 4 h respectively. For every concentration the resulting acidic pH was adjusted with diluted sodium hydroxide solution to the pH of the test system. Test water was coloured yellow.

Test organisms

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: zebrafish
- Strain: Brachydanio rerio (Hamilton-Buchanan)
- Source: West Aquarium, D-37431 Bad Lauterberg, Germany
- Age at study initiation: appr. 3 months
- Length at study initiation: 2,5 - 3.5 cm

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Post exposure observation period:

Observations were carried out during exposure at the beginning of the experiment and after 2 - 4, 24, 48, 72 and 96 hours.

Test conditions

Test temperature:

20.9°C - 21.4°C (treatment), 20.8°C - 21.2°C (control)

pH:

5.5 - 8.1 (treatment), 7.4 - 8.1 (control)

Dissolved oxygen:

7.0 - 8.7 mg/L (treatment); 7.8 - 8.7 mg/L (control)

Nominal and measured concentrations:

Nominal concentrations: 884 mg/L, 1250 mg/L, 1768 mg/L, 2500 mg/L, 3536 mg/L, 5000 mg/L, 7071 mg/L, 10000 mg/L
Measured concentrations were within the range of 95 to 102 % of the respective nominal concentrations

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass-aquaria 30 cm x 13.5 cm x 20 cm, 5 L per vessel
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1


TEST MEDIUM / WATER PARAMETERS
- pH , temperature and oxygen saturation were observed at the beginning, after 2-4, 24, 48, 72 and 96 h

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality and behavior of the test fish and control fish were observed at 2-4, 24, 48, 72, 96 h.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

> 10 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Details on results:

There was no mortality in the control as well as in treated fish at any observation time point. No behaviourial abnormalities were observed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

In this study the test item did not cause any mortalities to zebrafish after 96 h when tested with different concentrations up to 10000 mg/L (measured)

Executive summary:

The acute toxicity of the test item to fish (zebrafish) was determined according to test guideline of the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany (1984) at Bayer AG. A static test with concentrations 884, 1250, 1768, 2500, 3536, 5000, 7071, 10000 mg/L solution was conducted. Duration of the test was 96 h. 10 test organisms were exposed to the test solution respectively and the control. Water quality parameters pH-value, temperature and oxygen-saturation measured after 0, 2 -4, 24, 48, 72 and 96 h were determined to be within the acceptable limits. Test item analysis was carried out at 0, 24, 48, 72 and 96 h. Concentrations were above 95 % of the initial concentration.

The maximum test concentration of 10000 mg/L solution of the test item didn´t show any lethality at all observation time points up to 96 hours. In addition no behaviour abnormalities were observed.