Methyl O-(4-amino-3,5-dichloro-6-fluoropyridin-2-yloxy)acetate

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 Dec- 21 Dec 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Version / remarks:

Adopted in 1984

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methyl O-(4-amino-3,5-dichloro-6-fluoropyridin-2-yloxy)acetate

EC Number:

407-550-4

EC Name:

Methyl O-(4-amino-3,5-dichloro-6-fluoropyridin-2-yloxy)acetate

Cas Number:

69184-17-4

Molecular formula:

Hill formula: C8 H7 Cl2 F N2 O3 CAS formula: C8 H7 Cl2 F N2 O3

IUPAC Name:

methyl 2-[(4-amino-3,5-dichloro-6-fluoropyridin-2-yl)oxy]acetate

Details on test material:

- Name of test material (as cited in study report): Fluroxypyr methyl ester
- Substance type: pure substance
- Physical state: solid, fine black crystalline powder
- Analytical purity: 93.6% w/w
- Lot/batch No.: HJ 11 160402A
- Expiration date of the lot/batch: 18 November 1995
- Storage condition of test material: room temperature in the dark

Sampling and analysis

Analytical monitoring:

no

Test substrate

Vehicle:

yes

Details on preparation and application of test substrate:

- The test compound was applied as solutions in acetone prepared on the day of dosing. The dose concentrations were calculated to give the same volume at all dose levels. Negative control soil was treated with an equivalent volume of vehicle only. For each group, the dose was thoroughly mixed
with a small pre-mix of soil and the vehicle allowed to evaporate off prior to incorporation with the main soil bulk

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: Mr. D. Saunders, Fox Lane, Bourn, UK
- Weight at test initiation: 329-378 mg (mean range per replicate)

ACCLIMATION
- Acclimation period: 7 days

Study design

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test conditions

Test temperature:

19-21 °C

pH:

6.4 (adjusted with calcium carbonate)

Moisture:

34-35% dw

Details on test conditions:

TEST SYSTEM
- Test container: 1 L glass containers
- Amount of soil or substrate: 737 g mean wet weight per container
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per vehicle control: 4

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Soil texture (artificial soil)
- % Quartz sand: 70% w/w
- % Sphagnum peat: 10% w/w
- % Kaolin clay: 20% w/w
- Pretreatment of soil: calcium carbonate was added to the soil mixture to give a pH of approximately 6.4. The soil constituents were blended in the
proportions shown above in a large scale laboratory mixer and the moisture content was determined by drying a small sample


OTHER TEST CONDITIONS
- Photoperiod: continuous illumination
- Light intensity: approximately 460 lux.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): mortality at 7 and 14 days

VEHICLE CONTROL PERFORMED: yes

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8

Nominal and measured concentrations:

Nominal concentrations: control, 95, 171, 309, 556, 1000 mg/kg soil

Reference substance (positive control):

yes

Remarks:

chloroacetamide

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

7 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 3

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

309 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: weight

Details on results:

- Only two mortalities were reported in the 1000 mg/kg concentration group during the second week of the treatment period
- During the first week of treatment, weight loss was observed in the 556 mg/kg and 1000 mg/kg concentration groups. All groups lost weight during the second week of treatment

Results with reference substance (positive control):

- The LC values of chloroacetamide were determined in a similar study conducted between 29 August and 12 September 1991 and were as follows:
7d-LC50: 52 mg/kg soil
14d-LC50: 37 mg/kg soil