cis-4-[3-(p-tert-butylphenyl)-2-methylpropyl]-2,6-dimethylmorpholine

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07.-08.1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

GLP compliance:

yes (incl. QA statement)

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: culture from C.A.M.; Gestel, RIVM, NL-3720 Bilthoven
- Age at test initiation: < 1 year
- Weight at test initiation: ≥ 250 mg

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

21°C

pH:

5.7

Moisture:

water content at test initiation 26.3% (of soil dry weight)

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 1 L preservation glass jar with glass lids
- Amount of soil or substrate:
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- artificial soil according to OECD 207 in 1.0 L glass jars

OTHER TEST CONDITIONS
- Photoperiod: continuous illumination

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Mortality, behavioural effects, weight change

Nominal and measured concentrations:

Control, 197.5, 296.3, 444.4, 666.7, and 1000 mg a.s./kg soil dry weight.

Reference substance (positive control):

yes

Remarks:

Chloroacetamide

Key result

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

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Fenpropimorph caused no substance related mortality of the earthworms up to 1000 mg a.s./kg soil, the highest concentration tested. Reduction in worm biomass was measured in all test variants including the untreated control. Biomass development was not statistically significant inhibited. No other particular behavioural or morphological changes were observed. The results are summarized in table 1 below.

Table 1:   Effect of Fenpropimorph on earthworm (Eisenia fetida) mortality and biomass (14 d)
Concentration [mg a.s./kg soil dry weight]	Control	197.5	296.3	444.4	666.7	1000
Mortality [%]	0	0	2.5	2.5	0	0
Weight change [%]	-3.81	-2.88	-1.68	-0.46	-5.24	-10.19
Endpoints [mg a.s./kg soil dry weight]
LC50	> 1000
NOEC (mortality, biomass)	1000

Conclusions:

In a 14-d toxicity study with Fenpropimorph to earthworms (Eisenia fetida) no treatment related earthworm mortality was recorded. Therefore the LC50 was determined to be > 1000 mg a.s./kg, the highest concentration tested. The NOEC (mortality, biomass) was determined be 1000 mg a.s./kg soil (dry weight).

Description of key information

In a 14-d toxicity study (Krieg, 1999/11124) with fenpropimorph to earthworms (Eisenia fetida) no treatment related earthworm mortality was recorded. Therefore the LC50 was determined to be > 1000 mg a.s./kg, the highest concentration tested. The NOEC (mortality, biomass) was determined be 1000 mg a.s./kg soil (dry weight).

Key value for chemical safety assessment

Long-term EC10, LC10 or NOEC for soil macroorganisms:

1 000 mg/kg soil dw

Additional information

In addition, another acute toxicity test on earthworms was prepared (Fleischer, 2004/1003960) to examine the effects of fenpropimorph-acid (Reg.No. 231 346; main metabolite of fenpropimorph) on the mortality of the earthworm Eisenia fetida.
In a 14-d toxicity study with fenpropimorph-acid to earthworms (Eisenia fetida) no earthworm mortality was recorded. Therefore the LC₅₀ was determined to be > 1000 mg a.i./kg, the highest concentration tested. The NOEC (mortality, biomass) was determined be 1000 mg a.i./kg soil (dry weight).

 

A study on sub-lethal effects in earthworms was triggered by the persistence of the active substance in soil (DT90_field > 365 days). A study about reproduction effects has been performed with the fenpropimorph formulation BAS 421 12 F (Krieg, 2001/1001670). The tested formulation caused no negative impact on both survival and biomass development of parent earthworms at rates up to 8.0 L/ha (equivalent to > 18.80 mg a.s./kg test soil). No statistically significant influences on the reproduction rate were recorded at 1.0 L/ha, 2.0 L/ha and 4.0 L/ha. Higher test concentrations of 8.0 L/ha resulted in reduction of only 18.29% in the number of surviving offspring, which is considered to be ecologically non-relevant.