2,4'-difluorobenzophenone

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:

2006.07.10-2006.07.14

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OSPAR Commission 2005: Protocols on Methods for the Testing of Chemicals used in the Offshore Industry (reference number: 2005-11 [a revised version of agreement 1995-07])

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Modified according to OSPAR Commission 2006: Protocols on Methods for the Testing of Chemicals Used in the Offshore Industry

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,4'-difluorobenzophenone

EC Number:

206-441-7

EC Name:

2,4'-difluorobenzophenone

Cas Number:

342-25-6

Molecular formula:

C13H8F2O

IUPAC Name:

(2-fluorophenyl)(4-fluorophenyl)methanone

Details on test material:

2,4'-difluorbenzophenon
Liquid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: (Water accomodated fraction (WAF)): 20, 50, 100, 200, 500, 1000 ml WAF/l
- Sampling method: 2 x 50 ml of stock solution
- Sample storage conditions before analysis: Freezer at -21ºC

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Cyprinodon variegatus

Details on test organisms:

TEST ORGANISM
- Common name: Sheephead minnow
- Source: originally obtained from a stock culture at Opus Plus Ltd.(the former ERT Orkney water Technology Centre, and cultured at DHI since June 2003. Animals from this DHI culture was used for this study

ACCLIMATION
- Acclimation conditions : no acclimatation needed, test done under same conditions at same facility as test animals was optained from.

Study design

Test type:

semi-static

Water media type:

saltwater

Limit test:

no

Total exposure duration:

96 h

Test conditions

Test temperature:

20±0.5ºC

pH:

7.9-8.1

Dissolved oxygen:

> 70%

Salinity:

32 ‰

Nominal and measured concentrations:

Stock solution made by 1000 mg substance dissolved in 2000 ml test media. Nominal concentration: 500 mg/l.
Substance was not fully dissolved, therfore a test was taken from the middle of the volumetric flask (water accomodated fraction = WAF)
The stock solution was analysed at the beginning and by water replacement. Both times the analytical value was 37 mg/l.

Details on test conditions:

TEST SYSTEM
- Test vessel: 2 L aquariums containing 1 L test solution
- Renewal rate of test solution (frequency/flow rate): after 48 h.
- No. of organisms per vessel: 10

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol, CAS No. : 591-35-5, at 2.3 mg/L.

Results and discussion

Effect concentrations

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

7.1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

dissolved

Basis for effect:

mortality (fish)

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Mortality: 50% at 2.3 mg/l

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Mortality in controls < 10 %, oxygen > 60%, mortality with reference test within acceptable range, 20-80 %

Conclusions:

LC50(96 h) of 2,4'-difluorobenzophenone, CAS No. 342-25-6 is 7.10 mg/L for Cyprinodon variegatus