Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

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:
2002-05-27 to 2002-06-07
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Analytical monitoring:
yes
Details on sampling:
- Concentrations: Control and nominal concentration of 100 mg/l

- Sampling method: Duplicate samples of fresh (Control and 100 mg/l treatment excluding Daphnids) and old (Control and 100 mg/l treatment including Daphnids) test media were taken.

- Sample storage conditions before analysis: Samples were immediately frozen to approximately -20ºC.
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: The single test medium concentration of 100 mg/l was prepared by dissolving 30 mg of the test substance in 300 ml of water by stirring for 30 minutes at room temperature.

- Controls: Dilution water
Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM

- Common name: Water flea

- Strain: Clone 5

- Source: The University of Sheffield, U.K.

- Age at study initiation (mean and range, SD): 6 - 24 hours

- Method of breeding: Parthenogenetic reproduction

- Feeding during test: None


ACCLIMATION

- Acclimation conditions (same as test or not): yes

- Type and amount of food: not reported

- Feeding frequency: not reported

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h
Hardness:
250 mg/l (as CaCO3)
Test temperature:
21ºC
pH:
7.8 - 8.0
Dissolved oxygen:
8.0 - 8.4
Nominal and measured concentrations:
Nominal concentrations: Control and 100 mg/l

Measured concentration in 100 mg/l treatment at start of test: 78 mg/l

Measured concentration in 100 mg/l treatment at end of test: 99 mg/l

Results based on measured silicon concentrations
Details on test conditions:
TEST SYSTEM

- Test vessel: Beakers

- Type: closed

- Material, size, headspace, fill volume: glass, 100 ml, 50 ml headspace (approx.) and 50 ml fill volume

- Aeration: none

- Renewal rate of test solution (frequency/flow rate): none

- No. of organisms per vessel: 10

- No. of vessels per concentration (replicates): 2

- No. of vessels per control (replicates): 2

- Biomass loading rate: 1 daphnid/5 ml of test medium


TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: reconstituted fresh water prepared by mixing analar grade salts into purified water.

- Alkalinity: 0.8 mmol

- Ca/mg ratio: 4:1

- Conductivity:

- Culture medium different from test medium: no

- Intervals of water quality measurement: daily


OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: 16/8., light/dark

- Light intensity: 550-690 Lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobilization after 24 and 48 h.


TEST CONCENTRATIONS

- Spacing factor for test concentrations: Limit test at 100 mg/l

- Justification for using less concentrations than requested by guideline: Range-finding study result

- Range finding study

- Test concentrations: not reported

- Results used to determine the conditions for the definitive study: not reported
Reference substance (positive control):
no
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
>= 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
- Behavioural abnormalities: none

- Mortality of control: 0

- Other adverse effects control: none

- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none
Reported statistics and error estimates:
There were no toxic effects in the test and therefore statistical analysis of the results was not required.

No toxic effects were observed in the test.

Validity criteria fulfilled:
yes
Conclusions:
A 48-h EC50 value of >100 mg/l and NOEC of =100 mg/l have been determined for the effects of the test substance on mobility of Daphnia magna. It is likely that the test organisms were exposed primarily to the hydrolysis products of the substance.

Description of key information

Short-term toxicity to invertebrates: 48 hr EC50 >100 mg/l (measured) (highest concentration tested) (EU C.2) (CAS 2530-85-0). The observations in this study are attributed to the exposure of test organisms to the hydrolysis products in the test system.

Key value for chemical safety assessment

Additional information

A 48-h EC50value of >100 mg/l and NOEC of =100 mg/l (measured, highest concentration tested) have been determined for the effects of 3 -trimethoxysilylpropyl methacrylate (CAS 2530-85-0) on mobility of Daphnia magna. It is likely that the test organisms were exposed predominantly to the hydrolysis products of the substance.

The results of a second reliable test are also available. The test was conducted as a limit test at a concentration of 876 mg/L and no effects on mobility were observed.

The reliability of the results, reporting an EC50 of 399 mg/l from a third test could not be determined because there was insufficient information in the source to do so.

Refer to the discussion in the Section 6 endpoint summary (Section 7.0 of CSR) for further discussion of the approach to chemical safety assessment for this registration substance, and justification for read-across used.