OO-tert-butyl O-(2-ethylhexyl) peroxycarbonate

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reference 2

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

supporting 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

Justification for type of information:

Please refer to the QMRF and QPRF files provided under the section attached justification.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSAR R.6

Principles of method if other than guideline:

Estimation of BCF, BAF and biotransformation rate using BCFBAF v3.01

GLP compliance:

no

Specific details on test material used for the study:

SMILES: CCCCC(CC)COC(=O)OOC(C)(C)C

Test organisms (species):

other: fish

Details on estimation of bioconcentration:

BASIS INFORMATION
- Measured/calculated logPow: 5.2

BASIS FOR CALCULATION OF BCF
- Estimation software: BCFBAF v3.01
- Result based on measured log Pow of: 5.2

Key result

Type:

BCF

Value:

1 253 L/kg

Remarks on result:

other: QSAR predicted value. The substance is within the applicability domain of the model.

Type:

other: logBCF

Value:

3.098 dimensionless

Remarks on result:

other: QSAR predicted value. The substance is within the applicability domain of the model.

Details on kinetic parameters:

Biotransformation half-life (days): 2.09 (normalized to 10 g fish at 15°C)
Biotransformation rate (kM, normalized to 10 g fish): 0.3315/day

BCFBAF Program (v3.01) Results:

==============================

SMILES : CCCCC(CC)COC(=O)OOC(C)(C)C

CHEM  : Carbonoperoxoic acid, oo-(1,1-dimethylethyl) o-(2-ethylhexyl) ester

MOL FOR: C13 H26 O4

MOL WT : 246.35

--------------------------------- BCFBAF v3.01 --------------------------------

Summary Results:

Log BCF (regression-based estimate): 3.10 (BCF = 1.25e+003 L/kg wet-wt)

Biotransformation Half-Life (days) : 2.09 (normalized to 10 g fish)

Log BAF (Arnot-Gobas upper trophic): 2.92 (BAF = 830 L/kg wet-wt)

 

Log Kow (experimental): not available from database

Log Kow used by BCF estimates: 5.20 (user entered)

 

Equation Used to Make BCF estimate:

Log BCF = 0.6598 log Kow - 0.333 + Correction

 

Correction(s):                   Value

No Applicable Correction Factors

 

Estimated Log BCF = 3.098 (BCF = 1253 L/kg wet-wt)

 

===========================================================

Whole Body Primary Biotransformation Rate Estimate for Fish:

===========================================================

TYPE	NUM	LOG BIOTRANSFORMATION FRAGMENT DESCRIPTION	COEFF	VALUE
Frag	1	Linear C4 terminal chain [CCC-CH3]	0.0341	0.0341
Frag	1	Carbon with 4 single bonds & no hydrogens	-0.2984	-0.2984
Frag	5	Methyl [-CH3]	0.2451	1.2255
Frag	5	-CH2- [linear]	0.0242	0.1209
Frag	1	-CH-  [linear]	-0.1912	-0.1912
L Kow	*	Log Kow =  5.20 (user-entered)	0.3073	1.5982
MolWt	*	Molecular Weight Parameter		-0.6317
Const	*	Equation Constant		-1.5371
RESULT	LOG Bio Half-Life (days)		0.3203
RESULT	Bio Half-Life (days)		2.091
NOTE	Bio Half-Life Normalized to 10 g fish at 15 deg C

 

Biotransformation Rate Constant:

kM (Rate Constant): 0.3315 /day (10 gram fish)

kM (Rate Constant): 0.1864 /day (100 gram fish)

kM (Rate Constant): 0.1048 /day (1 kg fish)

kM (Rate Constant): 0.05895 /day (10 kg fish)

 

Arnot-Gobas BCF & BAF Methods (including biotransformation rate estimates):

Estimated Log BCF (upper trophic) = 2.904 (BCF = 801.6 L/kg wet-wt)

Estimated Log BAF (upper trophic) = 2.919 (BAF = 829.9 L/kg wet-wt)

Estimated Log BCF (mid trophic)  = 3.020 (BCF = 1047 L/kg wet-wt)

Estimated Log BAF (mid trophic)  = 3.105 (BAF = 1274 L/kg wet-wt)

Estimated Log BCF (lower trophic) = 3.052 (BCF = 1126 L/kg wet-wt)

Estimated Log BAF (lower trophic) = 3.269 (BAF = 1858 L/kg wet-wt)

 

Arnot-Gobas BCF & BAF Methods (assuming a biotransformation rate of zero):

Estimated Log BCF (upper trophic) = 4.033 (BCF = 1.078e+004 L/kg wet-wt)

Estimated Log BAF (upper trophic) = 5.356 (BAF = 2.272e+005 L/kg wet-wt)

Validity criteria fulfilled:

yes

Conclusions:

Using BCFBAF v3.01 the BCF value of the test item was calculated to be 1253 L/kg. The substance is within the applicability domain of the model.

Executive summary:

The BCF value was calculated using BCFBAF v3.01 as part of EPISuite v4.11 from US Environmental Protection Agency. The BCF value of the test item was calculated to be 1253 L/kg (EPI Suite, 2014).

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descripted using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

Description of key information

Using BCFBAF v3.01 the BCF value of the test item was calculated to be 1253 L/kg. The substance is within the applicability domain of the model.

Key value for chemical safety assessment

BCF (aquatic species):

1 253 L/kg ww

Additional information

According to ECHA's guidance on information requirements and chemical safety assessment chapter R.11 "PBT/vPvB assessment" (v3.0 ; June 2017 ; p. 66), "The option of waiving the bioaccumulation test according to Column 2 of REACH Annex IX can only be taken if the information from the experimental test is not required for the conclusion on the PBT/vPvB-properties". As a matter of fact, the substance is readily biodegradable, which means that the substance does not meet the P/vP criteria laid down under annex XIII of REACh regulation EC 1907/2006. Therefore, the substance is not considered PBT/vPvB. In addition, bioaccumulation is not a critical parameter for risk assessment as the risk assessment for secondary poisoning is not required, because the substance is readily biodegradable, in accordance with ECHA's guidance R.16 'Environmental exposure assessment" (v3.0 ; Feb 2016 ; pp. 24-25). Since the substance is not PBT/vPvB and no further hazard is identified, and for the sake of reduction of the use of vertebrates under REACh regulation (art. 25), bioaccumulation studies are not needed. The bioaccumulation study is waived.

As a supporting information, the BCF value was calculated using BCFBAF v3.01 as part of EPISuite v4.11 from US Environmental Protection Agency. The BCF value of the test item was calculated to be 1253 L/kg (EPI Suite, 2014).

 

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

 

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

 

Description of the prediction Model

The prediction model was descripted using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

 

Assessment of estimation domain

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.