3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid

Toxicity to soil microorganisms

Administrative data

Endpoint:

toxicity to soil microorganisms

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 217 (Soil Microorganisms: Carbon Transformation Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Sampling and analysis

Analytical monitoring:

no

Test substrate

Vehicle:

no

Details on preparation and application of test substrate:

AMENDMENT OF SOIL
- Type of organic substrate: lucerne

APPLICATION OF TEST SUBSTANCE TO SOIL
- Method: lucerne meal was mixed the the argricultural soil

Test organisms

Test organisms (inoculum):

soil

Study design

Total exposure duration:

28 d

Test conditions

Test temperature:

19.2 - 21.9 °C

Moisture:

45 % of WHC

Details on test conditions:

TEST SYSTEM
- Test container (type, material, size): glass flask (500 ml)
- Amount of soil: 200 g dw
- No. of replicates per concentration: 3
- No. of replicates per control: 3


SOIL INCUBATION
- Method: bulk

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Geographical reference of sampling site (latitude, longitude): 12.69 degrees East, 51.40 degrees north (Wassergut Canitz, Germany)
- History of site: fallow ground
- Treatments with pesticides or fertilizers: none since 2003
- Depth of sampling: 20 cm
- Soil texture
- % sand: 50.6
- % silt: 39.7
- % clay: 9.8
- Soil taxonomic classification: loamy sand soil
- pH (in water): 6.5
- Maximum water holding capacity (in % dry weigth): 38.02 %
- Cation exchange capacity (mmol/kg): 10.1 mmol/kg
- Pretreatment of soil: sieving through 2 mm mesh size
- Initial microbial biomass as % of total organic C: 3.59 %

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Carbon concentrations measured as oxygen consumption 0, 7, 14 and 28 days after treatment.

Nominal and measured concentrations:

Nominal test concentrations:
control, 0.037 and 0.37 mg/kg

Field application:
maximum single application rate of 0.028 kg/ha
10 fold application rate 0.28 kg/ha

Reference substance (positive control):

yes

Remarks:

Dinoterb

Results and discussion

Effect concentrations

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

>= 0.37 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

respiration rate

Results with reference substance (positive control):

Inhibition:
-24.8 % at 6.8 mg Dinoterb/kg soil dw
-42.0 % at 16 mg Dinoterb/kg soil dw
-49.0% at 27 mg Dinoterb/kg soil dw