1-Propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, N-(C8-18(even numbered) and C18 unsaturated acyl) derivs., hydroxides, inner salts

Biodegradation in water: screening tests

Description of key information

Experimental results from several guideline studies (e. g. OECD 301 A, 301 B, 301 D, 301 E) on the aerobic biodegradation of Coco AAPB, C12 AAPB and C8-18 AAPB are available.
The inherent biodegradability of C12-18 AAPB was proven in a Zahn-Wellens Test. The anaerobic biodegradability of Coco AAPB and C8-18 AAPB was investigated in studies conducted similar to OECD guideline 311.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

Several biodegradation screening tests under aerobic and anearobic conditions are available for the target substance C8 -18 and C18 unsatd. AAPB (Coco AAPB). Further aerobic as well as anaerobic biodegradation screening tests are available for the source substance and C8-18 AAPB. A justification for read-across is attached in IUCLID Chapter 13.

 

Aerobic biodegradation

C8 -18 and C18 unsatd. AAPB

A variety of different screening studies for C8 -18 and C18 unsatd. AAPB are available, confirming the readily biodegradability. One reliable study (Klimisch 1) was selected as key study and described in more detail.

 

The ready biodegradability of C8 -18 and C18 unsatd. AAPB was investigated in a study conducted according to EPA OPPTS 835.3120 (Sealed Vessel Carbon Dioxide Production Test) and ISO/DIS 14593 over a period of 28 days and using activated sludge as inoculum. The biodegradation rate was determined by measurement of CO2 evolution. Inoculum blank and procedural/functional control with the reference substance sodium benzoate performed.

C8 -18 and C18 unsatd. AAPB proved to be readily biodegradable and fulfilling the 10 -d window criterion (87.2% biodegradation after 28 d). The functional control reached the pass level >60% after 14 d.

 

Experimental results from several guideline studies (e. g. OECD 301 A, 301 B, 301 D, 301 E) on the aerobic biodegradation of C8 -18 and C18 unsatd. AAPB are available. The following results were obtained from studies fulfilling the validity criteria: (ISO/DIS 14593: 87.2 - 93 % biodegradation after 28 d; DOC Die-Away Test: 92 % degradation after 28 d; ; Closed-Bottle-Test: 86 % degradation after 28 d; Modified OECD Screening Test: 100 % biodegradation after 28 d). (Data are summariesed in an overview table in Annex I).

 

C12 AAPB

The ready biodegradability of C12 AAPB was investigated in a study conducted according to EU Method C.4-F (Determination of the "Ready" Biodegradability - MITI Test) over a period of 28 days and using an inoculum taken from a purifying plant for municipal and industrial effluents, from an industrial effluent purifying plant and surface water and surface soil from a river bank. The biodegradation rate was determined by measurement of oxygen consumption. Inoculum blank and procedural/functional controls with the reference substance sodium benzoate were performed. In deviation from guideline 2 instead of 3 bottles containing test material and inoculum were used. Furthermore, a bottle containing test substance in water only was not included in the tests. The test item proved to be readily biodegradable. After 28 days the percentage of biodegradability was 82 % based on ThOD (ThOD=0.7 mg O₂/mg; ThOD not further specified: ThODNH4 or ThODNO3) and 95 % based on COD (COD=0.60 mg O₂/mg). The functional control reached the pass level > 60 % after 14 d.

 

C12 -18 AAPB

The inherent biodegradation of C12 -18 AAPB was investigated in a study conducted according to DIN 38 412, Part 25 (1984) and which is equivalent or similar to OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test) over a period of 15 days and using non-adapted industrial activated sludge as inoculum. The substance proved to be inherently biodegradable (elimination: 90.8 % after 15 d; biodegradation: 89.4 % after 15 d). The adsorption to sludge was determined to 13 % after 3 h. The reference substance diethylene glycol was biodegraded by 96.6 % after 8 d. Based on these results it can be assumed that C12 -18 AAPB will be readily biodegradable in OECD Guideline tests on ready biodegradation. This assumption is supported by Zahn-Wellens tests with Coco AAPB where similar results were obtained and the ready biodegradability could be shown.

 

C8 -18 AAPB

C8 -18 AAPB proved to be readily biodegradable. In a study conducted according to OECD Guideline 301 B (Ready Biodegradability: CO₂Evolution Test) over a period of 28 days and using activated sludge obtained from a municipal wastewater treatment plant as inoculum, the test substance was biodegraded by 91.6 % after 28 d (10 d window criterion fulfilled). These results were supported by a further guideline study. In a supporting study conducted according to EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test), the test substance was biodegraded by 76.3 % after 28 d).

 

Anaerobic biodegradation

The anaerobic biodegradability of C8 -18 and C18 unsatd. AAPB was investigated in a study conducted according to ISO11734 (Water quality - Evaluation of the ultimate anaerobic biodegradability of organic compounds in digested sludge - Method by measurement of the biogas production) and equivalent or similar to OECD Guideline 311 (Anaerobic Biodegradability of Organic Compounds in Digested Sludge: Measurement of Gas Production) over a period of 60 days and using non-adapted digester sludge as inoculum. The biodegradation rate was determined by measurement of total biogas production. Inoculum blank and procedural/functional controls with the reference substance polyethylene glycol 400 were performed. The test item proved to be biodegradable under anaerobic conditions (total biodegradation: 80-90 % after 60 d). The functional control reached the pass level > 60 % after 60 d.

 

In a second study the anaerobic biodegradability of C8 -18 AAPB was investigated in a study conducted according to ECETOC Anaerobic Biodegradation (Technical Report No. 28; similar to OECD guideline 311) over a period of 62 days and digested sludge as inoculum.The biodegradation rate was determined by measurement of gas production and TIC. Inoculum blank, procedural/functional control with the reference substance sodium benzoate and toxicity control were performed. Deviations from guideline were not reported.

The test item proved to be well biodegradable under anaerobic conditions (ca. 80% after 62 d).The functional control reached the pass level >70% (80% after 62 d). In the toxicity control containing both test and reference item an inhibitory effect of the test item on the anaerobic biodegradation was not observed.

 

Conclusion

Experimental results from several guideline studies (e. g. OECD 301 A, 301 B, 301 D, 301 E) on the aerobic biodegradation of C8 -18 and C18 unsatd. AAPB, C12 AAPB and C8 -18 AAPB are available. Based on the results, C8 -18 and C18 unsatd. AAPB, C12 AAPB, and C8 -18 AAPB can be regarded as readily biodegradable. The inherent biodegradability of C12-18 AAPB was proven in a Zahn-Wellens Test. Based on these results, the AAPBs can be regarded as readily biodegradable.

The anaerobic biodegradability of C8 -18 and C18 unsatd. AAPB and C8-18 AAPB was investigated in studies conducted similar to OECD guideline 311. Based on the results of these studies, the AAPBs are considered to be biodegradable under anaerobic condition.