1,3-dimethylurea

Short-term toxicity to fish

Administrative data

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:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: DIN 38412 part L15

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

1,3-dimethylurea

EC Number:

202-498-7

EC Name:

1,3-dimethylurea

Cas Number:

96-31-1

Molecular formula:

C3H8N2O

IUPAC Name:

1,3-dimethylurea

Details on test material:

- Name of test material (as cited in study report): Dimethylharnstoff (1,3-Dimethylurea)
- Analytical purity: 97.5 %

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:The test solution was prepared by adding the test item to the test media without any pre-treatment. Subsequently the fish were placed into the test aquaria.

Test organisms

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Golden orfe
- Source: Fish farm Paul Eggers, 2354 Hohenwestedt, Germany
- Length at study initiation (length definition, mean, range and SD): 7.3 cm (range 6.9 - 7.9 cm)
- Weight at study initiation (mean and range, SD): 3.4 g (range 2.5 - 5.0 g)


ACCLIMATION
- Acclimation period: 3 days
- Type and amount of food: Growing feed F/B 50, ad libitum
- Feeding frequency: daily
- Health during acclimation (any mortality observed): no mortality observed

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96

Test conditions

Hardness:

2.5 mmol/l

Test temperature:

20 °C

pH:

7.3 - 7.5

Dissolved oxygen:

8.1 - 8.6 mg/l

Nominal and measured concentrations:

Nominal test concentrations:
1000, 2150, 4640, and 10000 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: All glass aquaria (30 x 22 x 24 cm)
- Fill volume: 10 l
- Aeration: slight
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 3.4 g fish/l test water

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Test water: reconstituted freshwater according to DIN 38412, Part II, 1982; prepared from fully demineralised tap water by adding: 294.0 mg/l CaCl2 * 2 H2O, 123.3 mg/l MgSO4 + 7 H2O, 63.0 mg/l NaHCO3, 5.5 mg/l KCl
- Ca/mg ratio: 4:1
- Conductivity: max 10 micro MHO


OTHER TEST CONDITIONS
- Photoperiod: 16 : 8 hours day-night regime

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality and symptoms of intoxication.after 1, 4, 24, 48, 72 and 96 hours.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2.2
- Results used to determine the conditions for the definitive study: LC50 896h) 1000 - 10000

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

4 600 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 2

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 10 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Results with reference substance (positive control):

48 h-LC50 of the positive control chloroacetamide: about 32 mg/l (corresponds to normal sensitivity).

Any other information on results incl. tables

Sublethal observations / clinical signs:

During the 96 h exposure to 1,3-dimethylurea, mortalities were as follows:

Nominal test / Cumulative mortality (%) after x hours
concentration/ 1 / 4 / 24 / 48 / 72 / 96 /
(mg/l
Control / 0 / 0 / 0 / 0 / 0 / 0 /
1000 / 0 / 0 / 0 / 0 / 0 / 0 /
2150 / 0 / 0 / 0 / 0 / 0 / 0 /
4640 / 0 / 0 / 0 / 0 / 0 / 0 /
10000 / 0 / 0 / 10 / 10 / 30 / 60 /


Symptoms of intoxication:

Nominal test / Symptoms of intoxication after x hours
concentration / 1 / 4 / 24 / 48 / 72 / 96 /
(mg/l)
Control / - / - / - / - / - / - /
1000 / - / - / - / - / - / - /
2150 / - / - / - / - / - / - /
4640 / - / - / - / - / - / - /
10000 / - / - / - / - / - / A /

Definitions of Symptoms:
-: No symptoms
A: Apathy