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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

NTA is readily biodegradable.

See also section 3.1.2.1.1 and 3.1.2.1.2 of the EU RAR for trisodiumnitrilotriacetate (EINECS 225 -768 -6), final report, 2005, which also contains the relevant ecotox data for nitrilotriacetic acid. This report is attached in section 13:

A series of laboratory degradation tests is available for NTA (see Table 3.1). In most cases the

acid or the Na-salt was added and not the complexed NTA. However, the test media generally

contain, beside trace metals, calcium and/or magnesium ions in over-stoichiometric amounts, the

respective complexes are formed thus being the active test substances.

The test results indicate that the Ca/Mg complexes are readily removed. For instance, in a

Modified OECD Screening Test conducted according to OECD guideline 301 E, NTA was

found to be readily biodegradable. Meeting the 10 days time window criterion, the substance

(initial concentration 50 mg/l) was completely degraded within 14 days, as measured by DOC.

The inoculum used was taken from river water treatment plant. The lag phase until degradation

started was 5 days (BASF, 1983b).

Several bacteria strains capable of growth with NTA were isolated from wastewater, soil and

sediment. An aerobic Chelatobacter strain a monooxigenase is responsible for the initial

oxidation, leading to iminodiacetate (IDA) and glyoxylate. IDA is subsequently oxidised to

glycine and glyoxylate by a membrane-bound dehydrogenase. Denitrifying bacteria contain a

dehydrogenase/nitrate reductase complex, catalysing the formation of IDA, glyoxylate and nitrite

from NTA and nitrate (Egli, 1992, 1994).

The reaction pathway supports the result of the standard tests that NTA is completely

mineralised after primary degradation. Accumulation of a stable metabolite is not expected.

See further the in section 13 attached RAR