A mixture of: propan-2-one-O,O'(methoxyvinylsilandiyl)dioxime; propan-2-one-O-(dimethoxyvinylsilyl)oxime; propan-2-one-O,O',O''-(vinylsilantriyl)trioxime

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February 22-24, 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

According to EU Method C.2, with GLP.

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: Crustacea, Cladocera
- Source: Daphtoxkit F (Daphnia magna; MicroBioTests Inc., Industriezone "De Prijkels", Venecoweg 19 , 9810 Nazareth, Belgium).
- Age at study initiation (mean and range, SD): less then 24 hours old
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg CaCO3/L

Test temperature:

20 ºC throughout the test period

pH:

Between 7.6 and 7.9 in the test substance medium

Dissolved oxygen:

The dissolved oxygen concentration was 9.3-9.5 mg/L in the test substance medium (9.6-9.8 mg/L in control) .

Nominal and measured concentrations:

100 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel:
Disposable multiwell test plates with 30 test wells with a transparent lid, provided with the testkit. Each plate has four
10 mL wells each (replicates A,B,C,D) for the control and for 5 concentrations. Additionally, for each concentration the plates are provided with "rinsing wells" to prevent dilution of the test substance during the transfer of the daphnia from the hatching petri dish to the test wells .
- Aeration: No extra aeration, but slight circulation of air is still possible when the lid of the test plate is closed.

OTHER TEST CONDITIONS
- Photoperiod: artificial light from 4 a.m. to 8 p.m.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Immobilization:
24 and 48 hours after start of exposure to the test substance the neonates were observed for their swimming behavior. Animals not able to swim within approximately 15 s after gentle agitation of the test container are evaluated as immobilized.
Additionally immobilized animals trapped at the surface were counted to evaluate a possible influence of the test substance to the water surface tension.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

dissolved

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities:
- Mortality of control: there was no immobilization in the negative control group
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: the test media were clear and colorless during the whole exposure time

Immobilization of neonates.

The nominal concentration of test substance equivalents is displayed.

The concentrations are presented in units of mg test substance equivalents / L to indicate that not the test substance but a variety of degradation products was tested.

Immobilization 24 hours after the start of exposure

	T.s.	Immobilised neonates / total number of neonates
Group	concentration	Number per replicate				Total	Total
	(mg/L)	A	B	C	D	number	%
Control	0	0 / 5	0 / 5	0 / 5	0 / 5	0 / 20	0
T.s.	100	0 / 5	0 / 5	0 / 5	0 / 5	0 / 20	0

Immobilization 48 hours after the start of exposure

	T.s.	Immobilised neonates / total number of neonates
Group	concentration	Number per replicate				Total	Total
	(mg/L)	A	B	C	D	number	%
Control	0	0 / 5	0 / 5	0 / 5	0 / 5	0 / 20	0
T.s.	100	0 / 5	0 / 5	0 / 5	0 / 5	0 / 20	0

T.s. test substance

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 value of the test substance, based on the nominal concentration of test substance equivalents at the start of the assay, was >100 mg/L. The No Observed Effect Concentration (NOEC) was ≥100 mg/L.

Executive summary:

The Acute Toxicity of the test substance to Daphnia magna was determined in a 48 hours static test (According to EU Method C.2). A total of 20 daphnias, divided into 4 replicates (5 daphnias each) were treated with a single dose of 100 mg/L (Limit test). A negative control group, exposed to reconstituted water only, was included. Daphnia immobilization was inspected at 24h and 48 h after the start of the test, as well as immobilized animals trapped at the surface were counted to evaluate a possible influence of the test substance to the water surface tension. The pH and the dissolved oxygen concentration were tested at the start and at the end of the test. The temperature was controlled at the start, after 24 hours and at the end of the test. Test validity criteria were fulfilled.

The 24 and 48 hours EC50 value of the test substance was > 100 mg/L. The No Observed Effect Concentration (NOEC) was ≥100 mg/L.

Description of key information

The Acute Toxicity of the test substance to Daphnia magna was determined in a 48 hours static test (According to EU Method C.2). The 24 and 48 hours EC50 value of the test substance was > 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

A total of 20 daphnias, divided into 4 replicates (5 daphnias each) were treated with a single dose of 100 mg/L (Limit test). Daphnia immobilization was inspected at 24h and 48 h after the start of the test, as well as immobilized animals trapped at the surface were counted to evaluate a possible influence of the test substance to the water surface tension. The temperature was controlled at the start, after 24 hours and at the end of the test.Test validity criteria were fulfilled.

The 24 and 48 hours EC50 value of the test substance was > 100 mg/L. The No Observed Effect Concentration (NOEC) was ≥100 mg/L.