4-tert-butylcyclohexyl acetate

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation: aquatic / sediment

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

Run on 2013-04

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 limited documentation / justification

Remarks:

The bioconcentration factor (BCF) of the substance was evaluated with the most recent model from BCFBAF model v3.01 from EPI Suite v4.1, which fulfilled all OECD principles. The substance is within the domain of the Arnot-Gobas BCFBAF model based on the fragments present in the BCFBAF database.

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSARs R.6, May 2008

Deviations:

no

Principles of method if other than guideline:

See QMRF and QPRF in "Attached background material" and in "Any other information on materials and methods incl. tables" (the QMRF is only available for the former version of the QSAR model).

GLP compliance:

no

Specific details on test material used for the study:

- log Pow: 4.8 (experimental result)

Radiolabelling:

no

Details on sampling:

Not applicable

Details on preparation of test solutions, spiked fish food or sediment:

Not applicable

Test organisms (species):

no data

Details on test organisms:

Not applicable

Test type:

other: QSAR

Water / sediment media type:

not specified

Hardness:

Not applicable

Test temperature:

Not applicable

pH:

Not applicable

Dissolved oxygen:

Not applicable

TOC:

Not applicable

Salinity:

Not applicable

Details on test conditions:

Not applicable

Nominal and measured concentrations:

Not applicable

Reference substance (positive control):

no

Details on estimation of bioconcentration:

Not applicable

Type:

BCF

Value:

234 L/kg

Basis:

whole body w.w.

Remarks on result:

other: Arnot-Gobas method, including biotransformation rate estimates, upper trophic. log BCF = 2.369

Type:

BCF

Value:

309.2 L/kg

Basis:

whole body w.w.

Remarks on result:

other: Arnot-Gobas method, including biotransformation rate estimates, mid trophic. log BCF = 2.490

Key result

Type:

BCF

Value:

334.6 L/kg

Basis:

whole body w.w.

Remarks on result:

other: Arnot-Gobas method, including biotransformation rate estimates, lower trophic. log BCF = 2.524

Details on kinetic parameters:

Not applicable

Metabolites:

Not applicable

Results with reference substance (positive control):

Not applicable

Details on results:

Based on the biodegradation potential of the substance, it's more relevant to consider the result including biotransformation rate estimates instead of the result assuming a biotransformation rate of zero.

Reported statistics:

Not applicable

Arnot-Gobas BCF model (Whole body Primary Biotransformation Rate estimate for fish):

TYPE	NUM	LOG BIOTRANSFORMATION FRAGMENT DESCRIPTION	COEFF	VALUE
Frag Frag Frag Frag Frag L Kow MolWt Const	1 1 4 4 2 * * *	Ester [-C(=O)-O-C] Carbon with 4 single bonds & no hydrogens Methyl [-CH3] -CH2- [cyclic] -CH- [cyclic] Log Kow = 4.80 (user-entered) Molecular Weight Parameter Equation Constant	-0.7605 -0.2984 0.2451 0.0963 0.0126 0.3073	-0.7605 -0.2984 0.9804 0.3850 0.0252 1.4752 -0.5085 -1.5058
RESULT RESULT NOTE		Log Bio Half-life (days) Bio Half-life (days) Bio Half-life Normalized to 10 g fish at 15°C		-0.2387 0.5772

Biotransformation rate constant:kM (rate constant) = 1.201 / day (10 gram fish).

Arnot-Gobas BCFBAF Methods (including biotransformation rate estimates):

Estimated Log BCF (upper trophic) = 2.369 (BCF = 234 L/Kg wet-wt).

Estimated Log BCF (mid trophic) = 2.490 (BCF = 309.2 L/Kg wet-wt).

Estimated Log BCF (lower trophic) = 2.524 (BCF = 334.6 L/Kg wet-wt).

Arnot-Gobas BCFBAF Methods (assuming a biotransformation rate of zero):

Estimated Log BCF (upper trophic) = 3.742 (BCF = 5515 L/Kg wet-wt).

Validity criteria fulfilled:

yes

Conclusions:

The worst case Arnot-Gobas BCF for the substance is estimated at 334.6 L/Kg wet-wt (log BCF = 2.524), for the lower trophic, including biotransformation rate estimates.

Executive summary:

The bioconcentration factor (BCF) of the substance was evaluated with the most recent model from BCFBAF model v3.01 from EPI Suite v4.1, which fulfilled all OECD principles. The substance is within the domain of the BCFBAF model based on the fragments present in the BCFBAF database.

Based on the biodegradation potential of the substance, it's more relevant to consider the result obtain with Arnot-Gobas Method, including biotransformation rate estimates instead of the result assuming a biotransformation rate of zero. The worst case Arnot-Gobas BCF for the substance is estimated at 334.6 L/Kg wet-wt (log BCF = 2.524), for the lower trophic, including biotransformation rate estimates.

Description of key information

Arnot-Gobas BCFBAF model v3.01 from EPI Suite v4.1, key data:

BCF = 334.6 L/kg whole body weight

Key value for chemical safety assessment

BCF (aquatic species):

334.6 L/kg ww

Additional information

The key data point is not experimental but the bioconcentration factor (BCF) of the registered substance was evaluated with the most recent model from BCFBAF model v3.01 from EPI Suite v4.1, which fulfilled all OECD principles. The substance is within the domain of the Arnot-Gobas BCFBAF model based on the fragments present in the BCFBAF database.

Based on the biodegradation potential of the substance, it's more relevant to consider the result obtain with the Arnot-Gobas Method, including biotransformation rate estimates instead of the result assuming a biotransformation rate of zero. The BCF values of the substance are lower than 500 L/kg in all three general trophic levels of fish (lower, middle and upper). The worst case Arnot-Gobas BCF for the substance is estimated for the lower trophic level at 334.6 L/Kg wet-wt (log BCF = 2.524), including biotransformation rate estimates.