2,2-difluoro-benzo[1,3]dioxole-4-carbaldehyde

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

(1984)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,2-difluoro-2H-1,3-benzodioxole-4-carbaldehyde

EC Number:

700-476-6

Cas Number:

119895-68-0

Molecular formula:

C8H4F2O3

IUPAC Name:

2,2-difluoro-2H-1,3-benzodioxole-4-carbaldehyde

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Composite samples (about 150 ml Per concentration and control) of each test concentration were drawn by mixing identical volumes of the test solutions taken from the approximate Center of the test vessels. They were taken immediately before exposure and after 72 hours exposure and kept at - 18OC to - 22OC until analysis.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

24°C +/- 1°C

pH:

0h => pH 7.6
72h => pH 8 - 9.9

Nominal and measured concentrations:

nominal measured 0h measured 72h
blank <0.01 mg/ml <0.01 mg/ml
1.23 mg/l 0.88 mg/ml <0.01 mg/l
3.7 mg/l 3.11 mg/ml <0.01 mg/l
11 mg/l 10.2 mg/ml 0.13 mg/l
33 mg/l 33.5 mg/ml 8.7 mg/l
100 mg/l 106.6 mg/ml 70.9 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 ml Erlenmey flasks stoppered with aluminium caps, on Lab-shaker, 50 ml test solution per flask
- Initial cells density: 10100 cells/ml

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Photoperiod: continuous illumination cold white fluoresent light, 128 µE/m2 sec +/- 15% (approx. 8000 lux)


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: Ce11 densities were measured at 24, 48 and 72 hours exposure on a "TOA" cell Counter.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.28 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 2

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

< 0.13 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

biomass

Applicant's summary and conclusion

Validity criteria fulfilled:

yes