A mixture of: propan-2-one-O,O'(methoxyvinylsilandiyl)dioxime; propan-2-one-O-(dimethoxyvinylsilyl)oxime; propan-2-one-O,O',O''-(vinylsilantriyl)trioxime

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

bioaccumulation in aquatic species, other

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Internationally accepted method, EPI Suite, EPA (USA)

Justification for type of information:

See attached the QMRF and QPRF for the QSAR model.

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

Meylan, W.M., Howard, P.H, Aronson, D., Printup, H. and S. Gouchie. 1997. "Improved Method for Estimating Bioconcentration Factor (BCF) from Octanol-Water Partition Coefficient", SRC TR-97-006 (2nd Update), July 22, 1997; prepared for: Robert S. Boethling, EPA-OPPT, Washington, DC; Contract No. 68-D5-0012; prepared by: ; Syracuse Research Corp., Environmental Science Center, 6225 Running Ridge Road, North Syracuse, NY 13212.
Meylan, W.M., Howard, P.H., Boethling, R.S. et al. 1999. Improved Method for Estimating Bioconcentration / Bioaccumulation Factor from Octanol/Water Partition Coefficient. Environ. Toxicol. Chem. 18(4): 664-672 (1999).

Specific details on test material used for the study:

SMILES: N(O)=C(C)C

Key result

Type:

BCF

Value:

3.162 L/kg

Remarks on result:

other: (Log BCF from regression-based method = 0.500; log Kow used: 0.12)

The BCF of acetone oxime was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Validity criteria fulfilled:

not applicable

Conclusions:

The BCF of acetone oxime was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Executive summary:

Using the BCFBAF v3.01 model of EPI Suite v4.11, the BCF of acetone oxime was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Reference 2

Endpoint:

bioaccumulation in aquatic species, other

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Internationally accepted method, EPI Suite, EPA (USA)

Justification for type of information:

See attached the QMRF and QPRF for the QSAR model.

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

Meylan, W.M., Howard, P.H, Aronson, D., Printup, H. and S. Gouchie. 1997. "Improved Method for Estimating Bioconcentration Factor (BCF) from Octanol-Water Partition Coefficient", SRC TR-97-006 (2nd Update), July 22, 1997; prepared for: Robert S. Boethling, EPA-OPPT, Washington, DC; Contract No. 68-D5-0012; prepared by: ; Syracuse Research Corp., Environmental Science Center, 6225 Running Ridge Road, North Syracuse, NY 13212.
Meylan, W.M., Howard, P.H., Boethling, R.S. et al. 1999. Improved Method for Estimating Bioconcentration / Bioaccumulation Factor from Octanol/Water Partition Coefficient. Environ. Toxicol. Chem. 18(4): 664-672 (1999).

Specific details on test material used for the study:

SMILES: OC

Key result

Type:

BCF

Value:

3.162 L/kg

Remarks on result:

other: (Log BCF from regression-based method = 0.500; log Kow used: -0.77)

The BCF of methanol was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Validity criteria fulfilled:

not applicable

Conclusions:

The BCF of methanol was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Executive summary:

Using the BCFBAF v3.01 model of EPI Suite v4.11, the BCF of methanol was 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500).

Reference 3

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
The substance undergoes rapid hydrolysis (half-life < 1h) in aqueous to acetone oxime and the corresponding silanols. Also methanol was identified as a degradation product in the hydrolysis study included in this dossier. At the same time, silanols, i.e. dimethoxyvinylsilanol, methoxyvinylsilanediol and vinylsilanetriol, undergo continuous condensation reaction to produce higher molecular weight siloxanes which are in the molecular weight range large enough to be considered biologically unavailable. Therefore, the potential for bioaccumulation of the test substance is likely due to the acetone oxime and methanol. The estimated log octanol-water partition coefficients (Log Kow) for the degradation products acetone oxime and methanol are 1.20 and -0.63 (EPISuite, KOWWIN v1.68) respectively, which represents a low bioaccumulation potential (log Kow < 3). Furthermore, bioaccumulation of degradation products acetone oxime and methanol has been calculated (EPISuite, BCFBAF v3.01).

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

reference to other study

Reason / purpose for cross-reference:

reference to other study

Description of key information

Data waiving: The substance undergoes rapid hydrolysis (half-life < 1h) in aqueous to acetone oxime, methanol and the corresponding silanols. At the same time, silanols undergo continuous condensation reaction to produce higher molecular weight siloxanes which are in the molecular weight range large enough to be considered biologically unavailable. Therefore, the potential for bioaccumulation of the test substance is likely due to the acetone oxime and methanol which has been calculated (EPISuite, BCFBAF v3.01).

Key studies: Data from EPI-Suite, EPA (USA) / BCFBAF v3.01 calculation method. The BCF of the degradation products methanol and acetone oxime were calculated to be 3.162 L/kg.

Key value for chemical safety assessment

BCF (aquatic species):

3.162 L/kg ww

Additional information

Data waiving: The substance undergoes rapid hydrolysis (half-life < 1h) in aqueous to acetone oxime and the corresponding silanols. Also methanol was identified as a degradation product in the hydrolysis study included in this dossier. At the same time, silanols, i.e. dimethoxyvinylsilanol, methoxyvinylsilanediol and vinylsilanetriol, undergo continuous condensation reaction to produce higher molecular weight siloxanes which are in the molecular weight range large enough to be considered biologically unavailable. Therefore, the potential for bioaccumulation of the test substance is likely due to the acetone oxime and methanol. The estimated log octanol-water partition coefficients (Log Kow) for the degradation products acetone oxime and methanol are 1.20 and -0.63 (EPISuite, KOWWIN v1.68) respectively, which represents a low bioaccumulation potential (log Kow < 3). Furthermore, bioaccumulation of degradation products acetone oxime and methanol has been calculated (EPISuite, BCFBAF v3.01).

Key studies: Data from EPI-Suite, EPA (USA) / BCFBAF v3.01 calculation method. The BCF of the degradation products methanol and acetone oxime were calculated to be 3.162 L/kg.

According to Annex XIII to REACH, the substance is considered not to fulfil the criterion for bioaccumulation, since the estimated BCF is < 2000.