Reaction mixture of hydrogenated tallow alkyl amines with sebacic acid and lithium hydroxide

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-02-05 to 1999-05-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

December 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Version / remarks:

adopted July 17, 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Version / remarks:

January 1998

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: supplied by the sewage plant Groß-Zimmern, Germany
- Preparation of inoculum for exposure: The activated sludge used for this study was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was resuspended in tap water and again centrifuged. This procedure was repeated twice. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to its dry weight was determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 1.5 g dry material per liter were mixed with test water and then aerated until use.

Duration of test (contact time):

28 d

Initial conc.:

> 20 - < 20.1 mg/L

Based on:

other: nominal concentration

Parameter followed for biodegradation estimation:

other: Theoretical Oxygen Demand (ThOD)

Reference substance:

aniline

Parameter:

other: Theoretical Oxygen Demand (ThOD)NH4

Value:

28.8

Sampling time:

28 d

Key result

Parameter:

other: Theoretical Oxygen Demand (ThOD)NH4

Value:

26.2

Sampling time:

28 d

Details on results:

- 3.9 % degradation after 1 d
- 14.4 % degradation after 2 d
- 17 % degradation after 3 d
- 19.6 % degradation after 4 d
- 22.3 % degradation after 6 d
- 24.9 % degradation after 9 d
- 24.9 % degradation after 12 d
- 26.2 % degradation after 17 d
- 27.5 % degradation after 21 d
- 27.5 % degradation after 24 d
- 28.8 % degradation after 26 d
- 27.5 % degradation after 28 d

Results with reference substance:

- 0 % degradation after 1 d
- 0 % degradation after 4 d
- 41.8 % degradation after 5 d
- 51.8 % degradation after 6 d
- 57.8 % degradation after 7 d
- 62.7 % degradation after 8 d
- 66.7 % degradation after 10 d
- 68.7 % degradation after 12 d
- 70.7 % degradation after 15 d
- 75.7 % degradation after 20 d
- 77.7 % degradation after 23 d
- 82.7 % degradation after 26 d
- 85.7 % degradation after 28 d

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The percentage biodegradation did not exceed 60 % within the 10-day window. The test substance can therefore not be considered to be ready biodegradable.

Executive summary:

The test substance (EC: 433-100-1) was investigated for its biodegradability in a Manometric Respirometry Test over a period of 28 days according to OECD guideline no. 301F and EU method C.4D. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As reference compound aniline was tested simultaneously under same conditions as the test substance, functioned as a procedure control. After correction of the main biochemical oxygen demand of the inoculum controls at the end of the end of the 28 -day exposure period the test substance (EC: 433-100-1) was found to be biodegradable by 28.8 % and 26.2 %, based on ThODNH4 under the test conditions. The percentage biodegradation did not exceed 60 % within the 10 -day window. The test substance can therefore not be considered to be ready biodegradable.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2005-06-23 to 2005-09-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: ISO 14593: Water quality - Evaluation in an aqueous medium of the ultimate aerobic biodegradability of organic compounds -Method by analysis of inorganic carbon in sealed vessels (CO2 headspace test) March 1999

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: ISO 10634: Water quality - Guidance for the preparation and treatment of poorly water-soluble organic compounds for the subsequent evaluation of their biodegradation in an aqueous medium

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: The inoculum used was secondary effluent, from a laboratory treatment unit treating sewage from Newton Abbot sewage treatment works.
- Preparation of inoculum for exposure:
On the day of the test the effluent was filtered through a Whatman G/FC filter paper, and sparged with CO2 free air for at least two hours at pH 6.5 ± 0.2, to remove any dissolved carbon dioxide. After this time the effluent was neutralised to 7.0 ± 0.2 and allowed to stand for one hour. The prepared inoculum was added to the test bottles at a concentration of 10 % of the final volume.

Duration of test (contact time):

28 d

Initial conc.:

400 other: mg C/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

TOC removal

Details on study design:

TEST CONDITIONS
- Composition of medium: The test medium was made up according to the ISO guideline and, after preparation of the test bottles, contained the following nutrients per litre of deionised water: 85 mg of KH2P04, 217.5 mg of K2HPO4, 334 mg of Na2HPO4.2H20, 5 mg of NH4CL, 22.5 mg of MgSO x 7H2O, 36.4 mg of CaCl2.2H2O and 0.25 mg of FeCl3.6H2O.
- Solubilising agent: dissolving 260 mg of sebacic acid distearylamide and 130 mg of Tween 85 in 100 mL of hexane. After 30 minutes ultra sonic treatment this gave a milky white suspension, which appeared homogenous. When 1 mL of this was added to 85 mL mineral medium, and the solvent evaporated a slightly hazy suspension was formed with a few white particles in suspension.
- Test temperature: 22 ± 2 °C,
- pH: 7.0 ± 0.2
- pH adjusted: no
- Suspended solids concentration: 20mg
- Continuous darkness: yes


TEST SYSTEM
- Number of culture flasks/concentration: 3
- Measuring equipment: Dohrman DC 190 analyser, for IC analysis
- Test performed;
Control (inoculum blank) bottles contained mineral medium and inoculum. Reference substance bottles contained mineral medium, inoculum and sodium benzoate at nominal 20 mg C/L. Sebacic acid distearylamide bottles contained mineral medium, inoculum and sebacic acid distearylamide at a nominal concentration of 20 mg C/L, added using the solvent and emulsifier procedure described above. Solvent control bottles contained emulsifier and solvent in mineral medium with inoculum. Toxicity control bottles contained sebacic acid distearylamide, with solvent and emulsifier, and sodium benzoate, in medium and inoculum both at 20 mg C/L, the purpose of which was to show if sebacic acid distearylamide had an toxic effect on the bacteria. Positive control bottles were also prepared, which contained sodium benzoate and solvent and emulsifier, as above, to ensure these components did not have any inhibitory affect on the inoculum. In all cases any solvent was evaporated from the bottles before addition of the inoculum, by placing the open bottles in a fume cupboard for approximately three hours. Bottles containing sodium benzoate were dosed from a 686 mg T1 stock solution (equivalent to nominal 400 mg C/L in deionised water prepared on the exposure start day).

SAMPLING
- Sampling frequency: days 3, 6, 14, 21 and 28

CONTROL AND BLANK SYSTEM
- Inoculum blank: 3
- Toxicity control: 3
- Solvent control: 3
- Positiv control:3

Reference substance:

benzoic acid, sodium salt

Test performance:

Control (inoculum blank) bottles contained mineral medium and inoculum.
Reference substance bottles contained mineral medium, inoculum and sodium benzoate at nominal 20 mg C/L.
Sebacic acid distearylamide bottles contained mineral medium, inoculum and sebacic acid distearylamide at a nominal concentration of 20 mg C/L, added using the solvent and emulsifier.
Solvent control bottles contained emulsifier and solvent in mineral medium with inoculum.
Toxicity control bottles contained sebacic acid distearylamide, with solvent and emulsifier, and sodium benzoate, in medium and inoculum, both at 20 mg C/L, the purpose of which was to show if sebacic acid distearylamide had an toxic effect on the bacteria.
Positive control bottles were also prepared, which contained sodium benzoate and solvent and emulsifier, as above, to ensure these components did not have any inhibitory affect on the inoculum. In all cases any solvent was evaporated from the bottles before addition of the inoculum, by placing the open bottles in a fume cupboard for approximately three hours.
Bottles containing sodium benzoate were dosed from a 686 mg T1 stock solution (equivalent to nominal 400 mg C/L) in deionised water prepared on the exposure start day. Sufficient bottles were prepared to allow triplicate bottles of each set to be sacrificed on each analysis occasion (days 3, 6, 14, 21 and 28). The bottles were incubated at 22 ± 2 °C with shaking for up to 28 days. A number of bottles without inoculum were also prepared for organic carbon analysis on day 0.

Key result

Parameter:

% degradation (CO2 evolution)

Value:

39

Sampling time:

28 d

Details on results:

The inorganic carbon results for sebacic acid distearylamide show that it achieved a maximum biodegradation of 39 %.

Results with reference substance:

Sodium benzoate attained a maximum level of biodegradation (based on evolved carbon dioxide) of 110 %. More than 60 % degradation was achieved within 14 days, as expected for a biodegradable substance, thus confirming that the activated sludge contained viable organisms. Biodegradation is calculated as the ratio of measured carbon dioxide in the test bottle to the theoretical amount of carbon added at the start of the test. It is thought that biodegradation values of over 100 % may be due to excessive bacterial activity in the presence of a readily degradable carbon source.

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable

Conclusions:

Sebacic acid distearylamide achieved a maximum biodegradation of 39 %, and therefore cannot be considered "readily biodegradable". According to ECHA Guidance on Information requirements and CSR, R7b, Biodegradation above 20% of theoretical (measured as BOD, DOC removal or COD) may be regarded as evidence of inherent, primary biodegradability. Thus, the test item is considered as inherently biodegradable. Since the study was conducted with the one component of the submitted substance respectively the most difficult part to be degraded, the result can be adopted for the substance as such. Consequently, the substance is not expected to be persistent in the environment.

Executive summary:

A study was conducted according to ISO 14593 and ISO 10634 to determine the ready biodegradability of sebacic acid distearylamide. The inorganic carbon results for sebacic acid distearylamide, show that it achieved a maximum biodegradation of 39 %. The total CO2 evolution in the inoculum blank at the end of the test did not exceed 3.0 mg C/L, or 15 % of the carbon added as test substance, as required by the ISO guideline. After day three the inorganic carbon concentrations in the toxicity control bottles were higher than the sum of the concentrations in the sodium benzoate and sebacic acid distearylamide bottles, indicating the sebacic acid distearylamide did not have a toxic effect. The results from the positive control bottles, after correction for the solvent control, are consistently higher than those in the sodium benzoate bottles, indicating the solvent and emulsifier were not inhibitory to the bacteria. Sebacic acid distearylamide achieved a maximum biodegradation of 39 %, and therefore cannot be considered "readily biodegradable". According to ECHA Guidance on information requirements and CSR, R7b, Biodegradation above 20% of theoretical (measured as BOD, DOC removal or COD) may be regarded as evidence of inherent, primary biodegradability. Thus, the test item is considered as inherently biodegradable. Since the study was conducted with the one component of the submitted substance respectively the most difficult part to be degraded, the result can be adopted for the substance as such. Consequently, the substance is not expected to be persistent in the environment.

Description of key information

Two studies have been performed. A Manometric Respirometry Test according to Directive 92/69/EEC method C.4-D and OECD TG 301F over a period of 28 days and a Modified CO2 evolution test according to ISO 14593 and ISO 10634 to determine the ready biodegradability of sebacic acid distearylamide.
In a manometric respirometry test the test substance (EC: 433-100-1) was found to be biodegradable by an average of 27.5 % of ThODNH4 and was therefore not considered to be ready biodegradable or inherently biodegradable. In addition, a study was conducted according to ISO 14593 and ISO 10634 to determine the ready biodegradability of sebacic acid distearylamide as a model component as required by EU Authorities. Sebacic acid distearylamide achieved a maximum biodegradation of 39 %, and can therefore not be considered as "readily biodegradable". According to ECHA Guidance on Information requirements and CSR, R7b, Biodegradation above 20 % of theoretical (measured as BOD, DOC removal or COD) may be regarded as evidence of inherent, primary biodegradability. Thus, the test item is considered as inherently biodegradable. Since the study was conducted with the one component of the submitted substance respectively the most difficult part to be degraded, the result can be adopted for the substance as such. Consequently, the substance is not expected to be persistent in the environment.

 

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable, not fulfilling specific criteria

Additional information

Biodegradation in water

Two studies have been performed. A Manometric Respirometry Test according to Directive 92/69/EEC method C.4-D and OECD TG 301-F over a period of 28 days and a Modified CO2 evolution test according to ISO 14593 and ISO 10634 to determine the ready biodegradability of sebacic acid distearylamide:

Modified CO2 evolution test

A study was conducted according to ISO 14593 and ISO 10634 to determine the ready biodegradability of sebacic acid distearylamide as a model component as required by EU Authorities. The inorganic carbon results for sebacic acid distearylamide, show that it achieved a maximum biodegradation of 39 %. The total CO2 evolution in the inoculum blank at the end of the test did not exceed 3.0 mg C/L, or 15 % of the carbon added as test substance, as required by the ISO guideline. After day three the inorganic carbon concentrations in the toxicity control bottles were higher than the sum of the concentrations in the sodium benzoate and sebacic acid distearylamide bottles, indicating the sebacic acid distearylamide did not have a toxic effect. The results from the positive control bottles, after correction for the solvent control, are consistently higher than those in the sodium benzoate bottles, indicating the solvent and emulsifier were not inhibitory to the bacteria. Sebacic acid distearylamide achieved a maximum biodegradation of 39 %, and therefore cannot be considered "readily biodegradable". According to ECHA Guidance on Information requirements and CSR, R7b, Biodegradation above 20 % of theoretical (measured as BOD, DOC removal or COD) may be regarded as evidence of inherent, primary biodegradability. Thus, the test item is considered as inherently biodegradable. Since the study was conducted with the one component of the submitted substance respectively the most difficult part to be degraded, the result can be adopted for the substance as such. Consequently, the substance is not expected to be persistent in the environment.

Manometric Respirometry Test

The test substance (EC: 433-100-1) was investigated for its biodegradability in a Manometric Respirometry Test over a period of 28 days according to OECD guideline 301F and EU method C.4D. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As reference compound aniline was tested simultaneously under same conditions as the test substance, functioned as a procedure control. After correction of the main biochemical oxygen demand of the inoculum controls at the end of the end of the 28 -day exposure period the test substance (EC: 433-100-1) was found to be biodegradable by 28.8 % and 26.2 %, based on ThODNH4 under the test conditions. The percentage biodegradation did not exceed 60 % within the 10 -day window. The test substance can therefore not be considered to be ready biodegradable.