Methyl (2E)-2-cyano-3-(2,2-difluoro-1,3-benzodioxol-4-yl)prop-2-enoate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

(1984)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

methyl (2E)-2-cyano-3-(2,2-difluoro-1,3-benzodioxol-4-yl)prop-2-enoate

EC Number:

700-526-7

Cas Number:

1333488-95-1

Molecular formula:

C12H7F2NO4

IUPAC Name:

methyl (2E)-2-cyano-3-(2,2-difluoro-1,3-benzodioxol-4-yl)prop-2-enoate

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Composite samples (about 150 ml in duplicate) of each test concentration were drawn immediately before exposure from appropriate dilution of the stock solution and after 24 hours by mixing identical volumes of the test solutions taken from the approximate center of the test vessels. The samples were kept at - 18°C to - 22!C until analysis.

Test solutions

Details on test solutions:

Calculated amounts of the stock solution to produce the desired test concentrations were given into the water and were homogeneously distributed. The daphnia were then transfered into the beakers. Deposit and small parts of the test substance were swimming at the surface of the test vessels at all test times and concentrations.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Straus 1820
- Source: CIBA-GEIGY Ltd

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

24 h

Test conditions

Hardness:

240 mg CaCO3/l

Test temperature:

20 +/- 1°C

pH:

7.8 - 8.0

Dissolved oxygen:

98 - 99 %

Nominal and measured concentrations:

nominal:
10, 18, 32, 58, 100 mg test substance/l

measured:
< 0.01, <0.01, 0.4, 1.0, 0.9 mg test substance/l

Results and discussion

Effect concentrations

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 1 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: EC50 as final measured concentration

Any other information on results incl. tables

Immobilization after 24 h (initial number of daphnia = 20/test conc.)

Final mean measured concentration [mg/l]	Number of immobilized Daphnia vessel 1	Number of immobilized Daphnia vessel 1	Number of immobilized Daphnia vessel 1	Number of immobilized Daphnia vessel 1	Total number	Total %
Blank	0	0	0	0	0	0
< 0.01	0	0	0	0	0	0
< 0.01	0	0	0	0	0	0
0.04	0	0	0	0	0	0
1.0	0	0	0	0	0	0
0.9	1	0	2	1	4	20

Becauee of the poor water solubility of the the substance the recoveries at start of exposure range from 3.8 t o 11.8 % of the nominal valuee. A loss of test substance appeared between the highest and the lowest test concentrations due to the heterogeneous stock solution containing non-dissolved particles. At the end of exposure setteled down particles are at the origin of the poor recoveries.