Silicic acid, ethyl ester

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Evaluation of effect of test material on Pseudomonas putida (Bacteria) for 5 hours.

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

The Oxygen consumption test (Huls method) was performed for test material on Pseudomonas putida (Bacteria)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Pseudomonas putida

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

5 h

Test temperature:

25 degC

Nominal and measured concentrations:

0, 100, 500, 1000 and 2000 mg/l

Details on test conditions:

Test vessel: Four 100-ml von Loh bottles with ground glass stoppers
-Nine control bottles without the test substance were used as reference; four of these contained HgCl2 to determine the final oxygen content. At the end of testing
HCl was added to stop biochemical processes.

Reference substance (positive control):

not specified

Duration:

5 h

Dose descriptor:

EC10

Effect conc.:

> 2 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Conclusions:

The EC10 evaluted after 5 h based on the Oxygen consumption of test organims was observed to be 2000 mg/l

Executive summary:

The Oxygen consumption test (Huls method) was performed for test material on Pseudomonas putida (Bacteria). Four 100-ml von Loh bottles with ground glass stoppers were coated with the culture solution, the bacterial suspension, and the test substance in staged concentrations (0, 100, 500, 1000 and 2000 mg/l), were sealed without air, and were incubated for 5 to 6 hours at approximately 25 degC. Two were treated with HgCl2 solution to kill the bacteria, and serve to determine auto-oxidation grades of the test substance. Nine control bottles without the test substance were used as reference; four of these contained HgCl2 to determine the final oxygen content. At the end of testing HCl was added to stop biochemical processes. The EC10 evaluted after 5 h based on the Oxygen consumption of test organims was observed to be 2000 mg/l

Description of key information

Toxicity to microorganisms:

The Oxygen consumption test (Huls method) was performed for test material on Pseudomonas putida (Bacteria). Four 100-ml von Loh bottles with ground glass stoppers were coated with the culture solution, the bacterial suspension, and the test substance in staged concentrations (0, 100, 500, 1000 and 2000 mg/l), were sealed without air, and were incubated for 5 to 6 hours at approximately 25 degC. Two were treated with HgCl2 solution to kill the bacteria, and serve to determine auto-oxidation grades of the test substance. Nine control bottles without the test substance were used as reference; four of these contained HgCl2 to determine the final oxygen content. At the end of testing HCl was added to stop biochemical processes. The EC10 evaluted after 5 h based on the Oxygen consumption of test organims was observed to be 2000 mg/l

Key value for chemical safety assessment

EC50 for microorganisms:

2 000 mg/L

Additional information

Toxicity to microorganisms:

The Oxygen consumption test (Huls method) was performed for test material on Pseudomonas putida (Bacteria). Four 100-ml von Loh bottles with ground glass stoppers were coated with the culture solution, the bacterial suspension, and the test substance in staged concentrations (0, 100, 500, 1000 and 2000 mg/l), were sealed without air, and were incubated for 5 to 6 hours at approximately 25 degC. Two were treated with HgCl2 solution to kill the bacteria, and serve to determine auto-oxidation grades of the test substance. Nine control bottles without the test substance were used as reference; four of these contained HgCl2 to determine the final oxygen content. At the end of testing HCl was added to stop biochemical processes. The EC10 evaluted after 5 h based on the Oxygen consumption of test organims was observed to be 2000 mg/l