kresoxim-methyl (ISO);methyl (E)-2-methoxyimino-[2-(o-tolyloxymethyl)phenyl]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:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

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

EC Number:

604-351-6

Cas Number:

143390-89-0

Molecular formula:

C18 H19 N O4

IUPAC Name:

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

Details on test material:

- Name of test material (as cited in study report): Reg. No. 242 009
- Analytical purity: 94% active ingredient
- Batch No.: N 27

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Stock solution was prepared by adding 75 mg Reg. No. 242 009 to 100 ml water containing 0.01% Tween. The corresponding amounts (µl) were added to 60 ml algal nutrient solution
- Chemical name of vehicle: Tween
- Concentration of vehicle in test medium: 0.01%

Test organisms

Test organisms (species):

Ankistrodesmus bibraianus

Details on test organisms:

TEST ORGANISM
- Common name: unicellular green alga
- Strain: SAG B 61.81
- Source: Collection of algal cultures in Göttingen, Germany

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

22 ± 1 °C

pH:

ca. 8.0 - 9.2

Nominal and measured concentrations:

Nominal test concentrations: control, 0.003, 0.01, 0.03, 0.1, 0.3, 1.0, 3.0 mg/L
Recovery rate: n.a., n.a., n.a. = not analyzed
d.l. = below detection limit

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Material, total volume: Erlenmeyer flasks, 100 ml
- Initial cells density: 3E+4 cells/ml
- No. of vessels per concentration (replicates): 5
- No. of vessels per control (replicates): 5
- No. of vessels per vehicle control (replicates): 5

GROWTH MEDIUM
- Standard medium used: yes (M4 medium)

TEST MEDIUM / WATER PARAMETERS
- Intervals of water quality measurement: pH after 72 hours

OTHER TEST CONDITIONS
- Photoperiod: continuous uniform illumination
- Light intensity and quality: ca. 8000 lux

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: counting under a microscope
- Chlorophyll measurement: photometric (623 nm) after 24, 48, 72 hours

TEST CONCENTRATIONS
- Range finding study: yes

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

7 µg/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.:

63 µg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

- No morphological effects on the algae could be observed

Any other information on results incl. tables

The concentration control analysis showed only poor agreement between measured and nominal values. This is, however, mainly due to analytical problems deriving from the poor solubility of the test substance in water. Therefore it is not surprising that relatively larger amounts of the test substance were measured in the 1: 100 and 1: 1000 diluted stock suspensions than in the stock solution itself. Because of the analytical problems with the hardly water-soluble test substance the calculations are based on the nominal values.