Triethylamine

Endpoint summary

Additional information

Readily Biodegradability:

DECISION OF THE EU COMMISSION WORKING GROUP ON CLASSIFICATION AND LABELLING OF DANGEROUS SUBSTANCES:

this group (= regulators from authorities of different European countries) decided not to classify the substance due to ready biodegradability. See below extract from minutes of two meetings of the group from 1995:

(1) The Commission Working Group on the Classification and Labelling of dangerous substances agreed not to classify this substance as dangerous to the environment due to ready biodegradability:

The proposal was N; R51-53. CEFIC argued that the acute toxicity of this substance was in the R52 range. Furthermore CEFIC reported biodegradation tests indicating ready biodegradability within the 10 day time window and there was no reference as to whether adapted micro-organisms were used. CEFIC therefore proposed no classification. DE noted that the acute toxicity for algae and a not ready test result indicated N; R51-53. FR agreed with CEFIC that the substance needed no classification due to the ready biodegradation. UK also agreed that a ready test result in a biodegradation test should overrule a not ready test result and therefore agreed with no classification.

Reference: SUMMARY RECORD - Commission Working Group on the Classification and Labelling of dangerous substances: Environmental Effects; ECBI/39/95 - Rev. 1; 3-5 April 1995.


(2) The Commission Working Group on the Classification and Labelling of dangerous substances confirmed the decision not to classify the substance as dangerous for the environment.

Reference: SUMMARY RECORD - Commission Working Group on the Classification and Labelling of dangerous substances: Environmental Effects; ECBI/67/95 - Rev. 1; 20-22 June 1995.

Conclusion: The chemical should be regarded as readily biodegradable based on the decision of European regulators.

Discussion of available data:

Several studies are available, but these results can only be assigned as additional, supporting information: In former times (1977) BASF AG performed already an experimental study in the context of ready biodegradability for 10 days following no guideline, but using a scientifically acceptable method. The inoculum was industrial, adapted, activated sludge and TEA was stated to be biodegradable in water.

A study report for ready biodegradability published 2001 at Elf Atochem Inc. stated that the test substance is readily biodegradable due to the fact that 96 % degradation has occurred during a study period of 21 days. It is not indicated which inoculum or test system was used, just that it was done under aerobic conditions. 

The Japan Chemical Industry testing laboratory investigated the inherent biodegradability of TEA in 1992 according to OECD guideline 302 C. The inoculum was non-adapted activated sludge and an initial test material concentration of 30 mg/L was used. The test duration was 28 days under aerobic conditions. A degradation of 25 – 34 % was reported as test result in this case.

Conclusion: Based on the results of the available studies, the test substance is readily biodegradable.

To fulfill the intention of read-across, the following data are available:

BASF AG (1990) performed a screening test for biodegradation in water for the chemical similar substance tripropylamine. This was a ready biodegradability test according to OECD guideline 301 E. The inoculum was domestic, non-adapted activated sludge under aerobic conditions. The duration of the test was 28 days, with an initial concentration of 28 mg/L, based on test material (TEA). Due to the fact that only 0 – 10 % degradation was investigated the scientists stated that no biodegradation was observed under these conditions.

Another read-across was done to the chemical similar substance tributylamine (Muckle, 2010). The substance was tested for ready biodegradability according to OECD guideline 301 B. Activated sludge from a waste water treatment plant receiving mostly domestic sewage was used as inoculum. The test concentration was 20 mg/L organic carbon (nominal). Degradation in the two replicates at the end of the 10 -day window reached 43 % and 71 %, respectively. Due to a deviation during the degradation phase within replicates, degradation lay marginally below the pass level (57 % instead of 60 %). This might be due to dissolved carbon dioxide in the test flasks. At the end of the test this dissolved carbon dioxide is driven off by addition of HCl, leading to an improved correlation between the replicates. At the end of the test, the difference between the replicates was only 6.4 %. The mean degradation at the end of the test was 80 %. Therefore, form a scientific point of view, the tributylamine is considered as readily biodegradable according to OECD criteria.

According to REACH regulation, no further testing of biodegradation characteristics (water and sediment or soil) have to be conducted due to the fact that the substance triethylamine is considered as readily biodegradable regarding the decision of the EU Commission Working Group on Classification and Labelling of Dangerous Substances.