Butan-2-one O,O',O''-(methylsilylidyne)trioxime

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

activated sludge respiration inhibition testing

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
The analogue MAC3 component of the reaction mass Wasox-MMAC2, has a molecular structure similar to butan-2-one O,O',O''-(methylsilanetriyl)oxime and therefore, they also have comparable values for the relevant molecular properties for toxicity to microorganisms.
See attached reporting format.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 403.93 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(analogue substance)

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: (Based on read-across approach on an analogue)

Details on results:

Based on the experimental results on analogue substance Wasox-MMAC2 (EC50-3h > 300 mg/L for activated sludge of a predominantly domestic sewage), the read-across approach was applied and the EC50 (3h) for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 403.93 mg/L.

Validity criteria fulfilled:

not applicable

Conclusions:

Based on read-across approach from experimental data on analogue Wasox-VMAC2, the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 403.93 mg/L.

Executive summary:

An Activated Sludge, Respiration Inhibition Test was performed on analogue Wasox-MMAC2 according to the OECD Guideline 209 using activated sludge from a sewage treatment plant treating predominantly domestic sewage. The 3h-EC50 was determined to be > 300 mg/L, basis for effect: respiration rate. Based on these results, the read-across approach was applied and the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 403.93 mg/L.

Reference 2

Endpoint:

activated sludge respiration inhibition testing

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
The analogue VAC3 component of the reaction mass Wasox-VMAC2, has a molecular structure similar to butan-2-one O,O',O''-(methylsilanetriyl)oxime and therefore, they also have comparable values for the relevant molecular properties for toxicity to microorganisms.
See attached reporting format.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 390.45 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(analogue substance)

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Remarks on result:

other: (Based on read-across approach from an analogue)

Details on results:

Based on the experimental results on analogue substance Wasox-VMAC2 (EC50-3h > 300 mg/L) for activated sludge of a predominantly domestic sewage), the read-across approach was applied and the EC50 (3h) for EAC3 was calculated to be > 390.45 mg/L.

Validity criteria fulfilled:

not applicable

Conclusions:

Based on read-across approach from experimental data on analogue Wasox-VMAC2, the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 390.45 mg/L.

Executive summary:

An Activated Sludge, Respiration Inhibition Test was performed on analogue Wasox-VMAC2 according to the OECD Guideline 209 using activated sludge from a sewage treatment plant treating predominantly domestic sewage. The 3h-EC50 was determined to be > 300 mg/L, basis for effect: respiration rate. Based on these results, the read-across approach was applied and the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 390.45 mg/L.

Reference 3

Endpoint:

toxicity to microorganisms, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See attached reporting format.

Reason / purpose for cross-reference:

read-across source

Key result

Dose descriptor:

other: Toxicity

Effect conc.:

>= 726.66 mg/L

Remarks on result:

other: (Based on read-across approach from an analogue)

Validity criteria fulfilled:

not applicable

Conclusions:

Based on the read-across approach from analogue substance butanone oxime, butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be toxic to Pseudomonas sp. at 726.66 mg/L.

Executive summary:

Based on the read-across approach from analogue substance butanone oxime, butan-2-one O,O',O''-(methylsilanetriyl)oxime

was determined to be toxic to Pseudomonas sp. at 726.66 mg/L.

Reference 4

Endpoint:

toxicity to microorganisms, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
See attached reporting format.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

5 min

Dose descriptor:

other: EC50

Effect conc.:

1 101.52 mg/L

Remarks on result:

other: (Based on read-across approach from an analogue)

Validity criteria fulfilled:

not applicable

Conclusions:

Based on the read-across approach form experimental results on analogue butanone oxime, the 5 min-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime in Photobacterium phosphoreum was determined to be 1101.52 mg/L.

Executive summary:

Based on the experimental results on analogue substance butanone oxime where the 5 min-EC50 for Photobacterium phosphoreum was determined to be 955 mg/L, the read-across approach was applied and the 5 min-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be 1101.52 mg/L.

Reference 5

Endpoint:

toxicity to microorganisms, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
The analogue methyltriacetoxysilane has a molecular structure similar to butan-2-one O,O',O''-(methylsilanetriyl)oxime and therefore, they also have comparable values for the relevant molecular properties for toxicity to microorganisms.
See attached reporting format.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

136.87 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

(analogue substance)

Basis for effect:

other: Biodegradation

Remarks on result:

other: (Based on read-across approach from an analogue)

Validity criteria fulfilled:

not applicable

Conclusions:

Based on the experimental results on analogue substance methyltriacetoxysilane, the read-across approach was applied and NOEC (28 d) for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be 136.87 mg/L.

Executive summary:

A ready biodegradability manometic respirometry test was performed according to OECD Guideline 301 F on analogue methyltriacetoxysilane and 28 day-NOEC was determined to be 100 mg/L since the substance was readily biodegradable (79.5% of biodegradation at 28 days) and did not inhibit the degradation of the toxicity test (83.9% of biodegradation after 28 days) up to 100 mg/L under aerobic conditions. Based on this results, the read-across approach was applied and 28 day-NOEC for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be 136.87 mg/L under test conditions.

Description of key information

Weight of evidence: Read-across from experimental results on butanone oxime: butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be toxic to Pseudomonas sp.at 726.66 mg/L.

Weight of evidence: Read-across from experimental results on butanone oxime the 5 min-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be 1101.52 mg/L.

Weight of evidence: Read-across from experimental results on methyltriacetoxysilane: The 28 day-NOEC for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be 136.87 mg/L under test conditions.

Weight of evidence: Read-across from experimental results on Wasox-VMAC2: the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 390.45 mg/L.

Weight of evidence: Read-across from experimental results on Wasox-MMAC2: the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 403.93 mg/L.

Key value for chemical safety assessment

EC50 for microorganisms:

390.45 mg/L

EC10 or NOEC for microorganisms:

136.87 mg/L

Additional information

The toxicity to microorganism is analized by the read-across approach from analogue substances:

- Read-across from experimental results on butanone oxime: By the read-across from butanone oxime, the toxicity to microorganism of the hydrolysis product of the test item is analysed and covered.

- Read-across from experimental results on analogue silanes: By the read-across from analogue silanes (methyltriacetoxysilane, Wasox-VMAC2 and Wasox-MMAC2), the toxicity to microorganism of the silane part of the substance is analysed and covered, since both test item Butan-2 -one O,O',O''-(methylsilanetriyl)oxime, like methyltriacetoxysilane, Wasox-VMAC2 and Wasox-MMAC2, undergo rapid hydrolsyis in aqueous to corresponding silanols and at the same time, these silanols undergo continuous condensation reactions.

Read-across from experimental results on butanone oxime:

Weight of evidence: Based on the read-across approach from analogue substance butanone oxime, butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be toxic to Pseudomonas sp.at 726.66 mg/L.

Weight of evidence: Based on the experimental results on analogue substance butanone oxime where the 5 min-EC50 for Photobacterium phosphoreum was determined to be 955 mg/L, the read-across approach was applied and the 5 min-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was determined to be 1101.52 mg/L.

Read-across from experimental results on analogue silanes:

Weight of evidence: Based on the experimental results obtained in a ready biodegradability test (OECD 301F) performed on analogue methyltriacetoxysilane (28 day-NOEC = 100 mg/L), the read-across approach was applied and the 28 day-NOEC for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be 136.87 mg/L under test conditions.

Weight of evidence: Based on the experimental results obtained in an Activated Sludge, Respiration Inhibition Test (OECD 209) performed on analogue Wasox-VMAC2 (3h-EC50 > 300 mg/L, basis for effect: respiration rate), the read-across approach was applied and the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 390.45 mg/L.

Weight of evidence: Based on the experimental results obtained in an Activated Sludge, Respiration Inhibition Test (OECD 209) performed on analogue Wasox-MMAC2 (3h-EC50 > 300 mg/L, basis for effect: respiration rate), the read-across approach was applied and the 3h-EC50 for butan-2-one O,O',O''-(methylsilanetriyl)oxime was calculated to be > 403.93 mg/L.