rac-(1R,4S,4aR,8R,8aS)-9-(dichloromethylidene)-8-hydroxyoctahydro-1,4-methanonaphthalen-5(1H)-one

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:

04 December 2014 to 18 December 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Version / remarks:

1984

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

no

Details on sampling:

Not applicable

Vehicle:

no

Details on preparation and application of test substrate:

- Method of mixing into soil: On the day of the test start, the test item was mixed with a small quantity of finely ground quartz sand, such that the required test concentrations were achieved once mixed with the artificial soil (10 g treated sand per replicate). The test item mixture was then mixed thoroughly with the artificial soil by intensive stirring in a laboratory mixer.
- Controls: Quartz sand only

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: Reared under ambient laboratory conditions in the test facility.
- Age at test initiation: Adult worms (approximately 3 months old with clitellum)
- Weight at test initiation: 306 – 495 mg/worm

ACCLIMATION
- Acclimation period: Approximately 24 hours
- Acclimation conditions: Earthworms were acclimatised in a separate batch of the untreated artificial soil (mixed with horse manure).

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Post exposure observation period:

None reported

Test temperature:

19.2 – 21.5 ºC

pH:

Test start: 6.01 – 6.05
Test end: 5.80 – 5.86

Moisture:

Test start: 56.0 – 56.3 % of WHC
Test end: 55.2 – 55.9 % of WHC

Details on test conditions:

TEST SYSTEM
- Test container: 1 L glass container with a glass lid which allowed gaseous exchange
- Amount of soil or substrate: Approximately 751 g wet weight, corresponding to 556 g dry weight
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4

SOURCE AND PROPERTIES OF SUBSTRATE
- Composition: 10 % sphagnum peat, 0.5 % calcium carbonate, 20 % kaolin clay and 69.5 % industrial quartz sand (fine sand is dominant with more than 50 % of the particles between 50 and 200 μm)
- Maximum water holding capacity: 62.3 g/100 g dry soil
- Pretreatment of soil: One day before test start (day of application), the dry artificial soil was moistened by adding deionised water to adjust the water content to 40 to 60 % of WHC.

OTHER TEST CONDITIONS
- Photoperiod: Continuous lighting
- Light intensity: 460 lx, artificial light (Lumilux L58W)

EFFECT PARAMETERS MEASURED: The mortality was assessed after 7 and 14 days (worms that did not respond to a gentle mechanical stimulus applied to their front end were considered dead). Any behavioural and pathological symptoms were also recorded. Furthermore, the fresh weight of the surviving worms was determined at the start and end of the test. The physico-chemical parameters (water content and pH) of the artificial soil were determined at test start and at the end of the test.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2

Nominal and measured concentrations:

Nominal concentrations: 62.5, 125, 250, 500, 1000 mg a.i./kg soil d.w., equivalent to 66.1, 132, 264, 529, 1057 mg test item/kg soil d.w. (corrected for purity)

Reference substance (positive control):

yes

Remarks:

2-chloroacetamide

Key result

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

Remarks on result:

not determinable

Key result

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

500 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: biomass

Details on results:

- Mortality at end of exposure period: Mortality rates of 0 - 5.0 % were recorded in the test item treatment groups and 0 % mortality was observed in the control group.
- Changes in body weight of live adults (% of initial weight) at end of exposure period: No statistically significant change in biomass (difference in fresh weight of surviving worms between test start and day 14 of exposure) compared to the control (7.6 % biomass decrease) was observed at concentrations of 62.5, 125, 250 and 500 mg a.i./kg soil d.w., for which biomass decreases of 7.4, 8.1, 8.0 and 9.0 % were recorded, respectively. At a concentration 1000 mg a.i./kg soil d.w. the biomass decrease of 22.3 % was statistically significant compared to the control group
- Behavioural abnormalities: No abnormal behaviour or toxic symptoms of the worms were observed in the test item treatment groups or control group during the test.

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: 14-day LC50 = 23.1 mg a.i./kg soil d.w. (95 % confidence limits = 22.1 to 24.2 mg a.i./kg soil d.w.)
- Other: The reference item is routinely tested at concentrations of 14.1, 18.3, 23.8, 31.0 and 40.3 mg a.i./kg soil d.w.; the most recent study is dated 11 April 2014, study number R 14 10 48 002 S

Reported statistics and error estimates:

Fisher's Exact Binomial Test with Bonferroni Correction and the Williams-t-test (p ≤ 0.05, one-sided) were used to compare the control with the independent test item groups.

Table 1. Summary of results

Endpoint	Treatment group (mg a.i./kg soil d.w.)
	Control	62.5	125	250	500	1000
Mortality of adult worms after 14 days (%)	0.0	0.0	0.0	2.5	0.0	5.0
Mean biomass change at 14 days (mg/worm)	-28.5	-27.8	-30.3	-29.6	-33.2	-81.7*
Mean biomass change (0 -14 d) (%)	-7.6	-7.4	-8.1	-8.0	-9.0	-22.3

No statistically significant differences between the control and test item were calculated for mortality (Fisher’s Exact Binomial Test with Bonferroni Correction, p > 0.05, one-sided greater)

* Statistically significant compared to control (Williams-t-test, p ≤ 0.05, one-sided greater)

d.w.: dry weight (of artificial soil)

Validity criteria fulfilled:

yes

Remarks:

Adult mortality was 0 % after 14 days (must be ≤ 10 %)

Conclusions:

The 14-d LC50 was concluded to be > 1000 mg a.i./kg soil d.w., the highest concentration tested. The NOEC based on biomass was determined to be 500 mg a.i./kg soil d.w. and the NOEC based on mortality was determined to be 1000 mg a.i./kg soil d.w.

Executive summary:

The toxicity of the test item to earthworms (Eisenia fetida) was determined in a 14-day test with artificial soil, according to the OECD Guideline for Testing of Chemicals No. 207 (1984). Nominal concentrations of 62.5, 125, 250, 500, 1000 mg a.i./kg soil d.w. were tested, equivalent to 66.1, 132, 264, 529, 1057 mg test item/kg soil d.w. (corrected for purity). Additionally, a control was tested in parallel. On the day of the test start, the test item was mixed with a small quantity of finely ground quartz sand, such that the required test concentrations were achieved once mixed with the artificial soil (10 g treated sand per replicate). The 14-d LC50 was concluded to be > 1000 mg a.i./kg soil d.w., the highest concentration tested. The NOEC based on biomass was determined to be 500 mg a.i./kg soil d.w. and the NOEC based on mortality was determined to be 1000 mg a.i./kg soil d.w.

Description of key information

14-d LC50 > 1000 mg/kg soil dw, NOEC = 1000 mg/kg soil dw, artificial soil (Eisenia fetida), OECD 207, Friedrich 2015

Additional information

The toxicity of the test item to earthworms (Eisenia fetida) was determined in a 14-day test with artificial soil, according to the OECD Guideline for Testing of Chemicals No. 207 (1984). Nominal concentrations of 62.5, 125, 250, 500, 1000 mg a.i./kg soil d.w. were tested, equivalent to 66.1, 132, 264, 529, 1057 mg test item/kg soil d.w. (corrected for purity). Additionally, a control was tested in parallel. On the day of the test start, the test item was mixed with a small quantity of finely ground quartz sand, such that the required test concentrations were achieved once mixed with the artificial soil (10 g treated sand per replicate). The 14-d LC50 was concluded to be > 1000 mg a.i./kg soil d.w., the highest concentration tested. The NOEC based on biomass was determined to be 500 mg a.i./kg soil d.w. and the NOEC based on mortality was determined to be 1000 mg a.i./kg soil d.w.