Tall oil, maleated

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2023

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 309 (Aerobic Mineralisation in Surface Water - Simulation Biodegradation Test)

Version / remarks:

April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

effluent/surface water mixture, untreated

Details on source and properties of surface water:

A sample of Calwich Abbey Lake surface water (Staffordshire, UK) will be supplied by Land Research Associates (Lockington Hall, UK). The location, date and time of collection, depth of sampling of the water and appearance of the water will be recorded. The dissolved oxygen content, temperature, pH and conductivity of the water will be recorded at the time of collection. The water will be sieved (0.1 mm) prior to use on this study.
The surface water should be used as quickly as possible (within 1 week of collection). On receipt and until preparation of the test samples, the water will be stored in the dark under aerobic conditions at ca +4 °C.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Remarks on result:

not measured/tested

Remarks:

The study could not be initiated as radiolabelled test material was found being not adequate. Thus, new radiolabelled test material is currently produced to start the study with this new batch of radiolabelled material, accordingly.

Transformation products:

not specified

Remarks:

Results are still outstanding

Conclusions:

Currently, the study is still ongoing as it could not be concluded prior to the submission deadline (September 20th, 2022) and the exposure phase on this study will begin presumably in 2023, when new radiolabelled material becomes available. Thereafter, the soil biodegradation examinations will start and a draft report is expected by end of October, 2023. Once available, the robust study summary will be updated and a dossier update will be submitted again.

Reference 2

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2023

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 309 (Aerobic Mineralisation in Surface Water - Simulation Biodegradation Test)

Version / remarks:

April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

effluent/surface water mixture, untreated

Details on source and properties of surface water:

A sample of Calwich Abbey Lake surface water (Staffordshire, UK) will be supplied by Land Research Associates (Lockington Hall, UK). The location, date and time of collection, depth of sampling of the water and appearance of the water will be recorded. The dissolved oxygen content, temperature, pH and conductivity of the water will be recorded at the time of collection. The water will be sieved (0.1 mm) prior to use on this study.
The surface water should be used as quickly as possible (within 1 week of collection). On receipt and until preparation of the test samples, the water will be stored in the dark under aerobic conditions at ca +4 °C.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

benzoic acid, sodium salt

Remarks on result:

not measured/tested

Remarks:

The study could not be initiated as radiolabelled test material was found being not adequate. Thus, new radiolabelled test material is currently produced to start the study with this new batch of radiolabelled material, accordingly.

Transformation products:

not specified

Remarks:

Results are still outstanding

Conclusions:

Currently, the study is still ongoing as it could not be concluded prior to the submission deadline (September 20th, 2022) and the exposure phase on this study will begin presumably in 2023, when new radiolabelled material becomes available. Thereafter, the soil biodegradation examinations will start and a draft report is expected by end of October, 2023. Once available, the robust study summary will be updated and a dossier update will be submitted again.

Description of key information

To fulfill the testing requirement for ultimate degradation in surface water for the UVCB substance, the two main constituents were selected as surrogates for investigation. Maleated tall-oil fatty acid (CAS 6935-55-3) and maleated rosin (CAS 4559-23-3) were individually synthesized by reacting linoleic acid and rosin, respectively, with 14C-radiolabelled maleic anhydride, where one of the two carbonyl atoms was labelled with 14C. The two radiolabelled model substances were individually investigated in an OECD 309 study protocol.

Unfortunately, the radiolabelled test specimen, when arriving in the test facility, already had degraded significantly and thus, the requirement for >=95% radiolabelling was not fulfilled anymore. Hence, the biodegradation study could not be initiated as planned and radiolabelled material has to be re-synthesized first.

This has lead to significant delays and the two studies are not concluded. Once degradation results and a final report become available, the dossier will be updated.