2-Butenedioic acid, 2-methyl-, 1,4-bis(2-ethylhexyl) ester, (2Z)-

Mode of degradation in actual use

Administrative data

Endpoint:

mode of degradation in actual use

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Study period:

2016

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: EPISuite modelling by EPISuite v. 4.11 / STPWIN

Justification for type of information:

QSAR prediction: migrated from IUCLID 5.6

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: ECHA Guidance on QSARs and grouping of substances. May 2008.

Principles of method if other than guideline:

EPI Suite v. 4.11 / STPWIN modelling using the Biowin/EPA draft method, described by Clark et al. 1995 and Seth et al. 2008. The STP Model is based on fugacity principles and attempts to predict the fate of an organic chemical in a conventional wastewater treatment plant that uses activated sludge secondary treatment. The model estimates the fate of a chemical present in the influent as it becomes subject to removal by evaporation, biodegradation or other degradation processes, sorption to sludge, and loss in the final effluent.

Clark B, Henry JG, Mackay D. 1995. Fugacity analysis and model of organic chemical fate in a sewage treatment plant. Environ Sci Technol 29:1488-1494.
Seth R, Webster E, Mackay D. 2008. Continued development of a mass balance model of chemical fate in a sewage treatment plant. Water Res 42:595-604.

GLP compliance:

no

Type of study / information:

A QSAR modelling with EPISuite v. 4.11/STPWIN

Test material

Test material information

Constituent 1

Reference substance name:

1,4-bis(2-ethylhexyl) (2Z)-2-methylbut-2-enedioate

EC Number:

807-715-4

Cas Number:

1354569-12-2

Molecular formula:

C21 H38 O4

IUPAC Name:

1,4-bis(2-ethylhexyl) (2Z)-2-methylbut-2-enedioate

Constituent 2

Reference substance name:

SMILES CC(C(=O)(OCC(CC)CCCC))=CC(=O)(OCC(CC)CCCC)

IUPAC Name:

SMILES CC(C(=O)(OCC(CC)CCCC))=CC(=O)(OCC(CC)CCCC)

Test material form:

other: in silico

Results and discussion

Any other information on results incl. tables

STP Overall Chemical Mass Balance:

Process stream	g/h	mol/h	%
Influent	10	0.028	100.0
Primary sludge	2.18	0.0061	21.77
Waste sludge	0.00656	0.000019	0.07
Primary volatilisation	1.55 x 10^-6	4.4 x 10^-9	0.00
Settling volatilisation	1.85 x 10^-8	5.2 x 10^-11	0.00
Aeration off gas	5.95 x 10^-8	1.7 x 10^-10	0.00
Primary biodegradation	6.37	0.018	63.70
Settling biodegradation	0.0838	0.00024	0.84
Aeration biodegradation	1.36	0.0038	13.62
Final water effluent	0.00118	3.3 x 10 ^-6	0.01
Total removal	10	0.028	99.99
Total biodegradation	7.82	0.022	78.15

(Total removal maximum is 95 percent)

Applicant's summary and conclusion

Conclusions:

The STPWIN fugacity-based QSAR model estimated the test substance to biodegrade 78.15 % in a in a conventional wastewater treatment plant that uses activated sludge secondary treatment. The estimate for total removal % was 99.99 % (recommended maximum 95 %).

Executive summary:

The STPWIN fugacity-based QSAR model estimated the test substance to biodegrade 78.15 % in a in a conventional wastewater treatment plant that uses activated sludge secondary treatment. The estimate for total removal % was 99.99 % (recommended maximum 95 %). The modelling result can be considered as reliable with restrictions (Klimisch 2), as the model may overpredict biodegradability of structurally analogous compounds when using the BIOWIN output and EPA Draft Method option.