methyl (2E)-[2-(chloromethyl)phenyl](methoxyimino)acetate

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:

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:

2006

Report date:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): 520 F - Chlormethyloximether
- Physical state: solid/ dark green
- Analytical purity: 94.4 g / 100 g
- Batch No.: 31196-182
- Storage condition of test material: ambient temperature

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test concentrations were prepared by dilution of a stock dispersion. The concentration of the stock dispersion was 111.1 mg/L. The test substance was weighed in and treated by ultra sonification for 30 minutes. The stock dispersion was a dispersion with fine particles, which were homogenously distributed, so that the stock dispersion could be used to prepare the test batches.

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: unicellular green alga
- Strain: SAG 86.81
- Source (laboratory, culture collection): obtained at regular intervals from SAG (Collection of algal cultures in Göttingen) and kept in liquid culture in the Laboratory of Experimental Toxicology and Ecology
- Age of inoculum (at test initiation): 3 days

PRE CULTURE
- Seed-culture: A seed culture was incubated for 4 days at 23 °C ± 2 °C
- Final cell density: 150E+04 cells/ml

- Pre-culture: Seed-culture was taken to inoculate a pre-culture (initial cell density: 1 x 104 cells/mL). The pre-culture was
incubated for 3 days at 23 °C ± 2 °C.
- Final cell density: 92E+04 cells/ml

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21 - 25 °C

pH:

uninoculated (after 0 h): 7.9 - 8.2
uninoculated (after 72 h): 7.6 - 8.1
inoculated (after 72 h): 7.6 - 9.6

Nominal and measured concentrations:

Nominal test concentrations: control, 0.391, 0.781, 1.56, 3.13, 6.25, 12.5, 25, 50, 100 mg/L
Mean measured concentrations: -, 0.163, 0.438, 0.955, 1.57, 2.65, 5.76, 14.9, 32.2, 63.7 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, nominal volume, fill volume: Erlenmeyer flasks (nominal volume 250 mL) plugged with gas permeable siliconsponge caps, 250 ml, 100 ml
- Initial cells density: 1E+04 cells/ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Intervals of water quality measurement: temperature was continuously measured during the whole test period in the climate
chamber; pH in additional uninoculated parallels: after 0 h in parallel 5 (this parallel was disposed of after measurement), after 72 h in parallel 6 and in the inoculated parallel 1 of each concentration.

OTHER TEST CONDITIONS
- Photoperiod: permanent illumination
- Light intensity and quality: Artificial light, type universal white, about 6000 – 10000 Lux at a wave length of 400 - 700 nm

EFFECT PARAMETERS MEASURED:
- Determination of cell concentrations: after 72 h in a counting chamber (Neubauer improved) in replicate No. 2 of the inoculated control
- Chlorophyll measurement: In vivo chlorophyll-a-fluorescence (pulsed excitation with light flashes having a wavelength of 435 nm) after 0, 24, 48 and 72 h

TEST CONCENTRATIONS
- Range finding study: yes
- Results used to determine the conditions for the definitive study: EC50 range derived from 72 hour range finding: 10 - 100 mg/L

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

32.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

12.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

10.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 6

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

17.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 7

Duration:

72 h

Dose descriptor:

EC90

Effect conc.:

29.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 8

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

6.25 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Results with reference substance (positive control):

The ErC50 (72 h) of the control substance potassium dichromate was 0.880 mg/L (Date of the last control experiment: 4 Apr 2006

Any other information on results incl. tables

For an evaluation of the results the nominal concentrations should be used, since the effects observed in this test include effects of undissolved test substance of products of hydrolysis.