Methanesulfonamide, N-[2-[(4,6-dimethoxy-1,3,5-triazin-2-yl)carbonyl]-6-fluorophenyl]-1,1-difluoro-N-methyl-

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 Jun - 13 Jul 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Version / remarks:

1984

GLP compliance:

yes (incl. QA statement)

Remarks:

Ministerium für Arbeit, Gesundheit und Soziales des Landes Nordrhein-Westfalen

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

To obtain the nominal test concentrations of 1000, 562, 316, 178 and 100 mg a.s./kg dry weight soil, nominal amounts of 638, 359, 202, 114 and 64 mg test item were weighed into a petri dish respectively and quartz sand (washed and calcined) was added up to a final weight of 5 grams for each of the four replicates. Test item and quartz sand were transferred to a mortar and thoroughly mixed with a pestle. Each application mixture (5 g) was transferred separately to artificial soil (595 g dry weight) and mixed thoroughly using a laboratory mixer. To the control replicates 5 g of quartz sand (without test item) was mixed into the soil. Finally 59.5 mL of deionised water were added and mixed into each replicate to achieve between 40 % and 60 % of the maximum water holding capacity (WHCmax).

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Strain: Eisenia fetida andrei
- Common name: Earth worm
- Source: Laboratory culture, original source Prof. Graff, Forschungsanstalt für Landwirtschaft, 38104 Braunschweig, Germany
- Age at test initiation: Adult worms (more than two months old)
- Weight at test initiation: 0.34g (average)

BREEDING CONDITIONS
- According to BBA Proposal for OECD (ECO 85, = UPEC 15, February 1981)
- Temperature: 22 ±2 °C
- Light cycle: 12:12 hours light-dark
- Substrate: 70 % natural soil, 25 % peat and 5 % straw (dry weight in each case), animals transferred into fresh substrate at half yearly intervals
- Feeding: Dried cattle manure at 14 day intervals

ACCLIMATION
- Acclimation period: 24 hours
- Acclimation conditions: yes

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

20 ± 2 °C

pH:

6.0 - 6.1

Moisture:

water content in the artificial soil: 25.7 - 26.2 %
water content as % of WHCmax: 56.7 - 58.2 %

Details on test conditions:

TEST SYSTEM
- Test container: 1.5 liter preserving jars, covered with glass lids
- Amount of soil or substrate: 595 g dry weight test soil, resulting in approximately 803 g wet artificial soil
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4

PROPERTIES OF SUBSTRATE
- Composition: 10% Sphagnum peat, 20% Kaolinite clay, 69.6% industrial quartz sand (Sort: F 36), 0.4% Calcium carbonate
- Stability and homogeneity of test material in the medium: The dry components intensely mxed in a cement mixer
- Maximum water holding capacity: wetted with deionised water to reach to a content of 40 % - 60 % of the maximum water holding capacity

OTHER TEST CONDITIONS
- Photoperiod: constant light
- Light intensity: 400 - 800 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Seven days after the start of the study, the number of surviving earthworms was determined by spreading the soil onto an inert surface and removing the earthworms by hand. The surviving animals were then returned to the test container with the test soil. After 14 days, the weight, abnormal behaviour, observed symptoms as well as the number of surviving earthworms were determined. Earthworms which showed no reaction when prodded with a blunt probe were considered dead.

Nominal and measured concentrations:

Nominal test concentrations: 1000, 562, 316, 178 and 100 mg a.s./kg dry weight soil

Reference substance (positive control):

yes

Remarks:

Chloroacetamide

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality

Details on results:

No morphological and behavioural effects were observed.
Based on weight the Lowest Observed Effect Concentration (LOEC) was determined as 100 mg/kg soil dw. However, to a test concentration of 100 mg a.s./kg weight soil, the weight difference between control and treatment group were within 5 %. These weight alterations are considered to be well in the range of biological variation.

Results with reference substance (positive control):

The LC50 (14 days) was calculated to be 26.1 mg Chloroacetamide A.R. /kg dry weight soil (95 % confidence limits: 18.9 – 43.8 mg Chloroacetamide A.R. /kg dry weight soil). The LC50 was within the concentration range determined in international ring studies.

Table 1: Effects on the test organism

	Mortality (%)		Weight
	7 days	14 days	% mean	significance according to Williams-Test
control	0	0	+4
100 mg/kg	0	0	+1	+
178 mg/kg	0	0	-3	+
316 mg/kg	0	0	-5	+
562 mg/kg	0	0	-5	+
1000 mg/kg	0	0	-9	+

 

Description of key information

 Eisenia fetida LC50 (14d) > 1000mg a.s./kg soil dw. (nominal)

Additional information

One study is available on the short-term toxicity of triafamone (CAS No. 874195-61-6) to the earth worm Eisenia fetida (Leicher, 2010). The study was performed according to OECD guideline 207 and GLP. Based on weight the Lowest Observed Effect Concentration (LOEC) was determined as 100 mg a.s./kg soil dw. However, the weight difference between control and treatment group were within 5 %. These weight alterations are considered to be well in the range of biological variation. No mortality and no morphological and behavioural effects were observed during the 14 days test duration. Therefore the LC50 (14d) is above the highest test concentration of 1000 mg/kg soil dw.