α-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26-11-2007 to 06-12-2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 226 (Predatory Mite (Hypoaspis (Geolaelaps) Aculeifer) Reproduction Test in Soil)

Version / remarks:

OECD 2007: guideline for testing of chemicals. Predatory mite reproduction test, 8th draft

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Application method:

not specified

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 00512242
- Expiration date of the lot/batch: 27/06/2013
- 100.3% w/w purity

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

178.7 g of deionised water had to be added per kg dry artificial soil.
three days beofre starting the test, the dry artificial soil was prmoistened by adding 157.3 g deionized water to 1900 g dry aritifical sand stored in a closed container until use. At the start of the test, the premoistened soil was divided into portions of 411.4 g for the test item group and the control group. Afterwards the missing amount of sand was added to the control group. The test item was mixed directly with 20 g sand and added to the premoistened substrate

Test organisms (species):

Hypoaspis aculeifer

Animal group:

Acari (soil-dwelling predatory mite)

Details on test organisms:

TEST ORGANISM
- Common name: Hypoaspis (Geolaelaps) aculeifer Canestrini (Acari: Laelapidae)
- Source: the mites were obtained from a healthy laboratory rearing stock maintained at the test site
- Age at test initiation (mean and range, SD): adult mites (33 days after starting of the egg laying for synchronisation)
- Stage at test initiation:
- Weight at test initiation (mean and range, SD):
- Date of collection:
- Cultural background (if honeybees):
- Disease free: ]yes / no]
- Kept according to standard practices: yes / no

ACCLIMATION
- Acclimation period:
- Acclimation conditions (same as test or not):
- Feeding:
- Health during acclimation (any mortality observed):

RATIONALE FOR SELECTION OF SPECIES (if other than requested by test guideline):

Study type:

laboratory study

Limit test:

yes

Total exposure duration:

14 d

Test temperature:

19.0-21°C

pH (if soil or dung study):

ph day 0: 6.47-6.42
day 14: 7.41 - 7.45

Humidity:

day 0: 18.15-18.17 %
day 14: 17.66-17.68 %

Photoperiod and lighting:

16h/8 light dark regime

Details on test conditions:

- control and one test item: 8 replicates per test item treatments and control. 10 adult femals per treatment.
- test container: glass vessel volume 100 mg..
- test organisms were added withing 30 minutes after preparation of the final test substrate.
- artificial soil: 5% sphagum peat, 20% kaolin clay, 75% air-dried industrial sand, 0.06% calcium carbonate
- test item was mixed directly with the required amount of sand and added to the premoistened susbtrate.
Each batch was mixed thorougly by hand for 2 minutes before introduced to the test vessel. After mixing, 23.6 g of test substrate was filled into each test container.

Reference substance (positive control):

yes

Remarks:

Perfekthion (a.s.: dimethoate)

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:

reproduction

Details on results:

mortality: control: 3.8 %; 1000 mg/kg dw: 2.5%
control group: 287.5 juveniles (mean number)
Test item: 285.1 juveniles per replated. reduction compared to control was 0.8%

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: EC50 was 3.6 mg a.s./kg soil dw (95% C.L.: 3.4 - 3.8 mg a.s. soil dw)
- Other:

Reported statistics and error estimates:

fisher's exact test
shapiro-wilk's test and residual analysis
t-test pooled

Validity criteria fulfilled:

yes

Conclusions:

T000824 caused no statistically significant effects on mortality or reproduction of Hypoaspis (Geolaelaps) aculeifer up to and including 1000 mg/kg soil dw.

Description of key information

In the 14-day toxicity study with T000824 to mites the LC50 was determined. T000824 caused no statistically significant effects on mortality or reproduction of Hypoaspis (Geolaelaps) aculeifer up to and including 1000 mg/kg soil dw.