Methyl [3-(trimethoxysilyl)propyl]carbamate

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:

2002-08-27 to 2002-08-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Nominal concentrations: 0 (Control) and 100 mg/L

- Sampling method: Duplicate samples of the test media were taken at the start and end of the test.

- Sample storage conditions before analysis: Samples were analysed immediately after collection.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION

- Method: A nominal concentration of 100mg/L was prepared by mixing 602mg of test substance with 6 L of dilution water, and stirring for 97 hours

- Controls: Dilution water

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM

- Strain: Clone 5

- Source: Supplied in 1997 by the Umweltbundesamt, Institut für Wasser-, Boden- und Lufthygiene, Berlin, Germany

- Age at study initiation (mean and range, SD): <21 h

- Feeding during test: no

ACCLIMATION

- Acclimation period: 21 h

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

250 mg/L as CaCO3

Test temperature:

21 °C

pH:

7.8 - 7.9

Dissolved oxygen:

≥8.1 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentration: 0 (control) and 100 mg/L

At the beginning of the test the concentration was 103% of nominal; at the end of the test the concentration was 93-94%. Results are reported with respective to the nominal concentration.

Details on test conditions:

TEST SYSTEM

- Test vessel:

- Type: open

- Material, size, headspace, fill volume: Glass beakers, 250mL volume, 150mL test medium

- Aeration: no

- No. of organisms per vessel: 10

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

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

TEST MEDIUM / WATER PARAMETERS

- Source/preparation of dilution water: The reconstituted fresh water was prepared by adding analytical-grade salts to deionised water

- Alkalinity: 0.8 mmol/L

- Ca/mg ratio: 4:1

- Culture medium different from test medium: yes

- Intervals of water quality measurement: Start and end of test

OTHER TEST CONDITIONS

- Adjustment of pH: no

- Photoperiod: 16 h light, 8 h dark

- Light intensity: 490 lux

EFFECT PARAMETERS MEASURED: Mobility after 24 and 48 h.

TEST CONCENTRATIONS

- Spacing factor for test concentrations: NA, limit test

- Range finding study: results not reported

Reference substance (positive control):

yes

Remarks:

Potassium Dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis products

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

but exposure is to hydrolysis products

Basis for effect:

mobility

Details on results:

- Mortality of control: 0

Results with reference substance (positive control):

Not reported

Reported statistics and error estimates:

There were no toxic effects observed in the test and therefore statistical analysis of the results was not required.

Table 1. Results of analysis of test media 

Nominal concentration of test substance (mg/L)	Measured test substance concentration at start of test (mg/L)*	Measured test substance concentration after 96 hours (mg/L)*	Nominal concentration of substance taking percentage of active ingredient into account (mg/L)**	Measured test substance concentration at start of test as percentage of nominal	Measured test substance concentration after 48 hours as percentage of nominal
0 (Control)	Not applicable	Not applicable	Not applicable	Not applicable	Not applicable
100 (Rep 1)	98.84	89.83	95.92	103	94
100 (Rep 2)	98.97	89.09	95.92	103	93

*Calculated from measured Dissolved Organic Carbon (DOC) concentration and taking percentage of carbon in the test substance and molecular weight (237.326) of the substance into account.

**Percentage active ingredient of the substance is 95.92%

There were no toxic effects at the only nominal test concentration of 100 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

A 48-hour EC50 value of >100 mg/L and a NOEC of ≥100 mg/L have been determined for the effects of the test substance on mobility of Daphnia magna based on nominal exposure concentrations of the substance. The test substance hydrolyses in water and it is therefore likely that the test organisms were primarily exposed to the hydrolysis products of the substance.

Description of key information

EC50 (48 h) > 100 mg/l (nominal) based on immobilisation of Daphnia magna (OECD 202)

Additional information

One experimental study is available investigating the toxicity of methyl-N-[3-(trimethoxysilyl)propyl]carbamate (CAS 23432-62-4) to freshwater invertebrates (Ibacon, 2002). A 48-hour EC50 value of >100 mg/l and a NOEC of ≥100 mg/l have been determined for the effects of the test substance on mobility of Daphnia magna based on nominal exposure concentrations of the substance. Since the substance is expected to hydrolyse rapidly in contact with water (DT50: 3.0 h at 20 - 25 °C, pH 7), the result from this study mainly investigated the possible effects of the hydrolysis products (Methyl-N-[3-(trihydroxysilyl)propyl]carbamate and methanol).