Aluminium trilactate

Biodegradation in water: screening tests

Description of key information

The ready biodegradation of Aluminium trilactate (93.0% a.i.) was investigated in a study conducted according to EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test; 30 May 2008) and OECD guideline 301 B adopted July 17, 1992 over a period of 28 days and using an inoculum obtained from activated sludge freshly obtained from a predominantly domestic municipal sewage treatment plant. The biodegradation rate was determined by measurement of carbon dioxide evolution.
In this test Aluminium trilactate was readiliy biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Additional information

The ready biodegradation of Aluminium trilactate (93.0% a.i.) was investigated in a study conducted according to EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test; 30 May 2008) and OECD guideline 301 B adopted July 17, 1992 over a period of 28 days and using an inoculum obtained from activated sludge freshly obtained from a predominantly domestic municipal sewage treatment plant. The biodegradation rate was determined by measurement of carbon dioxide evolution.

Inoculum blank, procedural/functional control with the reference substance Sodium acetate and 2 toxicity controls with reference substance and test substance (at 12 mg TOC/L = 35 mg/L test substance and 36 mg TOC/L = 100 mg/L test substance) were performed.

The relative biodegradation was 79% (mean of 2 replicates). Furthermore, biodegradation of at least 60% was reached within a 10-day window. Thus, Aluminium trilactate was readily biodegradable in this modified Sturm test.

In both toxicity controls more than 25% biodegradation occurred within 14 days (55% at 12 mg TOC/L = 35 mg/L test substance and 54% at 36 mg TOC/L=100 mg/L test substance, based on ThCO2). Therefore, the test substance was assumed not to inhibit microbial activity at both concentrations tested.

This result is further supported by a biodegradation screening test on Lactic acid:

The ready biodegradation of Lactic acid was investigated in a study conducted according to EU Method C.5 (Degradation: Biochemical Oxygen Demand; December 1992) and EU Method C.6 (Degradation: Chemical Oxygen Demand; December 1992) over a period of 20 days and using an inoculum obtained from activated sludge originating from an oxidation ditch treating domestic sewage. The biodegradation rate was determined by measurement of oxygen consumption. Information on inoculum blank and toxicity control were not given. A procedural/functional control with the reference substances Sodium acetate and Glucose/Glutamic acid were performed.

This study is regarded as reliable with restrictions and satisfies the guideline requirements for ready biodegradation.The test item proved to be readily biodegradable (67% degradation after 20 d).The functional control reached the pass level >60% after 5 d.

No further testing of biodegradation according to REACH regulation Annex VIII, 9.2, column 2 and Annex IX, 9.2, column 2 is considered necessary due to ready biodegradation of Lactic acid and the inorganic nature of Aluminium.