2,6-difluorobenzamide

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003-01-17 to 2003-02-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with analytical monitoring

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2,6-difluorobenzamide

EC Number:

241-972-8

EC Name:

2,6-difluorobenzamide

Cas Number:

18063-03-1

Molecular formula:

C7H5F2NO

IUPAC Name:

2,6-difluorobenzamide

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 100 mg/L
- Sampling procedure: Samples for analytical determination of the concentration were taken within the first hour after the start of exposure and at the end of the exposure after approx. 96 hours. Water samples were taken from the middle of the test vessel using a glass pipette and were transported to the analytical laboratory in volumetrie flasks, which were rinsed with test solution before they were filled.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test concentrations were prepared separately for each test vessel. The test substance was weighed into a beaker. The defined volume of test water was filled into the test vessel. An aliquot from the test water in the test vessel was taken and mixed with the test substance using an ultra turrax and the mixture was poured into the test vessel and the whole test batch was homogenized again with an ultra turrax.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Source: Forellenzucht Trostadt GbR, Dorfstrasse 7, 98646 Trostadt, Germany
- Age at study initiation: Approx. 4 months
- Length at study initiation: 5.6 cm (5.0 - 6.1 cm)
- Weight at study initiation: 1.48 g (1.02 -1.79 g)
- Feeding during test
- Hatching date: Sep 15, 2002
- Arrival at the testing facility: Nov 11,2002
- Diet: Ecostart 17 (Bio Mar), supplier Kofu Tiernahrung, Betriebsstätte Wesel, Hafenstr. 11 - 13, 46483 Wesel, Germany, ad libitum, additionally generally on workdays frozen brine shrimp (artemia).
- Withdrawal of feed: During the last day before start of exposure
- Medical treatment: None during acclimatization
- Mortality during the last week before start of exposure: 0.2%
- Acclimation period: 14 days
- Acclimation conditions (same as test or not):Same as test conditions

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test conditions

Hardness:

Approx. 2.5 mmol/L = 250 mg/L CaC03

Test temperature:

Approx. 12°C

pH:

Generally 7.5 - 8.5

Dissolved oxygen:

> 60% throughout the test period

Nominal and measured concentrations:

Nominal concentrations: 0 and 100 mg/L
Measured concentrations were within ± 10 % of the nominal values. Therefore, the results were based on nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria with stainless steel frame (60 cm long, 35 cm wide, 40 cm high)
- Fill volume: 30 L
- Aeration: None
- No. of organisms per vessel: 10
- No. of vessels per concentration: 3
- No. of vessels per control: 2
- Biomass loading rate: 0.5 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: According to guideline
- Alkalinity: Approx. 5.5 mmol/L
- Ca/mg ratio: 8/1
- Conductivity: Approx. 550 µS/cm (at 25°C)
- Intervals of water quality measurement: Daily

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light, 8 hours dark
- Light intensity: Approx. 82 - 280 Lux (the light intensity is determined in regular intervals at the surface of the aquaria)

EFFECT PARAMETERS MEASURED: Mortality, symptoms

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

>= 100 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.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 3

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Effect concentrations 4

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Mortality, symptoms

Details on results:

- Behavioural abnormalities: None
- Mortality of control: None