N-methyl-3-(trimethoxysilyl)propylamine

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:

27 - 29 Apr 2016

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)

Version / remarks:

2004

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

2008

GLP compliance:

yes (incl. QA statement)

Remarks:

Staatlisches Gewerbeaufsichtsamt Hildesheim, Germany

Analytical monitoring:

yes

Details on sampling:

- Concentrations and sampling method: at the start of the exposure intervals (0 and 24 h), sampling was carried out after preparation of the limit concentration. At the end of the exposure intervals (24 and 48 h), samples were taken directly from the test vessels. Only the hydrolysis product of the test item was analytical verified, since the test substance hydrolysis very rapidly.
- Sample storage conditions before analysis: all samples were stored at room temperature until sample preparation and in an autosampler until start of analysis, if necessary

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 100 mg/L of the test item were weighed directly into the dilution water (ISO test water) one day before the start of the exposure. The solution was stirred with a magnetic stirrer at approx. 1100 rpm for 24 h at room temperature. Thereafter, the solution was allowed to stand for 2.5 h for complete sedimentation of undissolved particles. The solution was removed from the vessel by a siphon from the approximate center of the water body.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: clone 5
- Source: Institut fur Wasser-, Boden- und Lufthygiene (WaBoLu), Berlin, Germany
- Age of parental stock (mean and range, SD): 2 - 24 h, juvenile daphnids were removed from the culture vessels at the latest 22 h before the start of the exposure and discarded. The juveniles born within this period of max. 22 h preceding the exposure were used for the test after an acclimatization phase of at least 2 hours in the dilution water. No first brood progeny was used for the test.
- Breeding: in 2 - 3 L glass vessels with approx. 1.8 L culture medium (Elendt M4), at 20 ± 2 °C, in an incubator with 16 h illumination. Daphnids were fed at least 5 times per week with unicellular green algae with a dencity of > 10^6 cells/mL

ACCLIMATION
- Acclimation period: at least 2 h in dilution water

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

19 - 20 °C

pH:

7.12 - 7.92

Dissolved oxygen:

7.78 - 8.48 mg/L

Nominal and measured concentrations:

0 (control), 100 mg/L (nominal)

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 mL glass beaker, loosely covered with watch glasses
- Fill volume: 20 mL
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): after 24 h (daphnids were transferred by pipette in new prepared vessels)
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to guideline
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH-value, dissolved oxygen concentration were measured at the start of the exposure intervals (0 and 24 h) in one additional replicate (without daphnids) of the limit concentration and the control. At the end of the exposure intervals (24 and 48 h), the water quality parameters of the old media were measured in all replicates (containing daphnids) of the limit concentration and the control. Additionally the pH, dissolved oxygen concentration, temperature, conductivity and total hardness of the dilution water were measured prior to the start of the exposure (0 h) and the water renewal (24 h).

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16/8 h light/dark cycle
- Light intensity: max 1340 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : the immobilization was determined after 24 and 48 h

RANGE-FINDING STUDY
- Test concentrations: 1,10 and 100 mg/L
- Results used to determine the conditions for the definitive study: no immobilization was identified. Therefore the highest test concentration was chosen for the performance of the definitive test.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

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:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Mortality of control: no

Results with reference substance (positive control):

- Results with reference substance valid: yes
- EC50 (24 h) = 1.95 mg/L (CI: 1.14 - 3.3 mg/L)

- The measured concentrations of the hydrolysis product of the test item were in the range of 102 to 115% of the nominal value at the start (0 and 24 hours) and at the end of the exposure intervals (24 and 48 hours). Therefore, effect results are expressed in nominal values.

Validity criteria fulfilled:

yes

Conclusions:

In the limit test with 100 mg/L of the test item, no effects on Daphnia magna were observed.

Description of key information

EC50 (48 h) > 100 mg/L (nominal, OECD 202, D. magna)

Additional information

A reliable study is available for the toxicity of N-methyl-3-(trimethoxysilyl)propylamine (CAS 3069-25-8) to aquatic invertebrates according to OECD 202 and GLP standards (Noack Laboratories, 2017b). The test organism Daphnia magna was exposed for 48 h in a semi-static test regime to a single test item concentration of 100 mg/L (nominal). Analytical monitoring was performed by LC-MS. The hydrolysis product of the test substance was verified since the substance hydrolysis very rapidly.

Recoveries were between 102 and 115% of the nominal values in fresh and aged media. No toxic effects on Daphnia magna were identified up to the tested concentration, resulting in an EC50 (48 h) > 100 mg/L (nominal).