Diammonium [N,N-bis[2-[bis(carboxymethyl)amino]ethyl]glycinato(5-)]ferrate(2-)

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial plants: short-term

Data waiving:

other justification

Justification for data waiving:

other:

Description of key information

No toxicity to terrestrial plant tests have been performed with DTPA-Fe(NH4)2.

As supporting information the results of toxicity to terrestrial plants for a number of EDTA-complexes is included in this dossier. These results are not recalculated to DTPA-Fe(NH4) as these results are not read across and are only included to demonstrate the low terrestrial toxicity observed for these EDTA-complexes and anticipated similar low toxicity of DTPA-complexes for the terrestrial compartment.

One toxicity to terrestrial plant tests is performed with EDTA-ZnK2 according to OECD 208 using three different plant species. the lowest NOEC of 125 mg test item/kg dw was observed for shoot wet weight of Brassica napus (rape). The lowest EC50 of 491 mg test item/kg dw was also observed shoot wet weight of Brassica napus (rape). The test item contained 90.4% active ingredient. The effect data based on active are then: NOEC of 113 mg a.i./kg dw was observed for shoot wet weight of Brassica napus (rape). The lowest EC50 of 444 mg a.i./kg dw also for Brassica napus (rape)

One toxicity to terrestrial plant tests is performed with EDTA-FeNa according to OECD 208 using three different plant species. the lowest NOEC of 37 mg test item/kg dw was observed for shoot wet weight of Glycine max (soy bean). The lowest EC50 of 430 mg test item/kg dw was also observed shoot wet weight but for Brassica napus (rape). The test item contained 100% active ingredient. The effect data based on active are therefore identical to that of the test item.

The study from Fiebig (2019) which was performed with EDTA-CuK2 according to OECD TG 208 gave a lowest EC50 of 225 mg test substance/kg dw for the number of emerged seedlings of soybean. The batch of EDTA-CuK2 had an active ingredient content of 92%. The EC50 based on active ingredient is then 207 mg a.i./kg dw.

Two additional older supporting study results with EDTA salts or complexes are available which evaluated different end-points (vegatative vigour and seedling emergence) in different plant species. In the 21d veg vigour study (Evangelou et al., 2006) a true NOEC could be established, while in the 14d seedling emergence test (Geebelen et al., 2002) no effect was observed at the highest tested dose.

As a worst-case the result of the lowest value observed i.e. a NOEC of 37 mg/kg dw is used for DTPA-Fe(NH4)2.

Key value for chemical safety assessment

Long-term EC10, LC10 or NOEC for terrestrial plants:

37 mg/kg soil dw

Additional information

The hazard assessment of DTPA-Fe(NH4)2 reveals neither a need to classify the substance as dangerous to the environment, nor is it a PBT or vPvB substance. The substance is expected to have a low potential for adsorption based on its ionic structure under environmental relevant pH conditions and its low log Kow , the low log Kow also indicates that the substance will not be bioaccumulative. There are no further indications that the substance may be hazardous to the environment.