Diammonium dihydrogen ethylenediaminetetraacetate

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

GLP compliance:

no

Remarks:

(Published) Study not peformed for REACH purposes. Therefore, GLP-compliance was not an issue for publication.

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

EDTA were applied in deionized water solution into artificial soil (35 % dry weight moisture content).

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

no data available

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Post exposure observation period:

no data available

Test temperature:

20 °C

pH:

no data available

Moisture:

35 % of maximum holding capacity

Details on test conditions:

Glass jars were used as test containers. 750 g of artificial soil which had been treated with one of the test chemicals (or a control with no chemicals) were placed in each jar. Ten E. fetida each with live weights of approximately 1 mg were added to each jar. There were four replicates of each chemical and dose.

Nominal and measured concentrations:

0, 0.1, 1.0, 10.0, 100.0, 1000.0 and 10000.0 mg/kg dry weight soil.

Reference substance (positive control):

not specified

Key result

Duration:

14 d

Dose descriptor:

EC50

Effect conc.:

156.46 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 136.01 - 179.98

Results with reference substance (positive control):

no data available

Reported statistics and error estimates:

Data were analyzed statistically by analysis of variance using S.A.S. software.
The LD50 values were estimated using Trimmed Spearman–Karber Version 1.5 (S.E.P.A. Cincinnati, Ohio) designed for analysis of mortality data from acute chronic toxicity tests.

Validity criteria fulfilled:

not specified

Conclusions:

The 14 day LC50 of EDTA to earthworms (Eisenia foetida) was estimated to be 156 mg/kg dry weight soil.

Executive summary:

The 14 day LC50 of EDTA to earthworms (Eisenia foetida) was estimated to be 156 mg/kg dry weight soil.

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: CFC 7539
- Expiration date of the lot/batch: 14 May 2024
- Purity: 100%

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

- Method of mixing into soil (if used): The respective test item amount was weighed out for a stock solution (nominal: 2220 mg/100 mL, actual: 2220 mg/100 mL) and dispersed in demineralised water. The stock solution was further diluted to the respective application solutions. The application solution and additional demineralised water were added to the artificial soil to adjust the humidity of the artificial soil to a moisture of 54 % of the WHCmax. Subsequently, the test medium was thoroughly mixed to ensure a homogenous distribution and about 555 g SDW were filled into each test vessel.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Source: Breeding stock culture maintained at the test facility
- Age at test initiation (mean and range, SD): 2 – 12 months, with clitellum
- Weight at test initiation (mean and range, SD): 0.40 - 0.54 g

ACCLIMATION
- Acclimation period: The earthworms were conditioned to artificial soil two days prior to the start of exposure.

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

20 ± 2°C

pH:

5.70 - 6.32

Moisture:

22.6 - 24.6 % of DW

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 1.5 L glass vessels closed with transparent and perforated lids
- Amount of soil or substrate:
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4

OTHER TEST CONDITIONS
- Photoperiod: 24h
- Light intensity: 400-800 lx

EFFECT PARAMETERS MEASURED: Mortality was recorded after 14 days exposure time.

Nominal and measured concentrations:

Nominal: 3.16, 10, 31.6, 100 and 316 mg/kg dw

Reference substance (positive control):

yes

Remarks:

2-Chloroacetamide

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

129 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

A statistically significant mortality was observed in the test item concentrations 100 mg/kg and 316 mg/kg soil dry weight, whereas no mortalities were observed in the control and the test item concentrations 3.16 to 31.6 mg/kg soil dry weight after 14 days of exposure
No significant pathological symptoms or changes in the earthworm behaviour were observed in the control as well as in the test item concentrations 3.16 to 31.6 mg/kg soil dry weight after 7 and 14 days of exposure. In the test item concentration 100 mg/kg soil dry weight and 316 mg/kg soil dry weight, significant changes in earthworm behaviour were observed after 7 and 14 days.

Validity criteria fulfilled:

yes

Conclusions:

The substance is harmful to earthworms.

Executive summary:

A statistically significant mortality was observed in the test item concentrations 100 and 316 mg/kg soil dry weight after 14 days of exposure, whereas no mortalities were observed in the control and the test item concentrations 3.16 to 31.6 mg/kg soil dry weight. Consequently, the LC50 was determined to be 129 mg/kg soil dry weight.

Reference 3

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Remarks:

No long-term data are considered to be needed , since substance is biodegradable and not adsorptive.

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Category justification document is attached in chapter 13.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

129 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: EDTA-FeNa

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

156.46 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: EDTA

Description of key information

LC50(14d) = 129 mg/kg dw (nominal) for mortality of Eisenia fetida (OECD 207, read across)

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil macroorganisms:

129 mg/kg soil dw

Additional information

Since no studies are available investigating the toxicity of Diammonium dihydrogen ethylenediaminetetraacetate (CAS 20824-56-0) to soil macroorganisms, the assessment was based on studies conducted with subcategory 1a member Edetic acid (CAS 60-00-4) and subcategory 1b member Sodium feredetate (CAS 15708-41-5) in a read across approach. This is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. Grouping of substance and read across approach. Further justification for suitability of read across between Subcategory 1 members is given within the category justification attached to chapter 13.

The key study with Sodium feredetate was performed according to OECD guideline 2007 and GLP using Eisenia foetida as test organism (Winkelmann 2019). A statistically significant mortality was observed in the test item concentrations 100 and 316 mg/kg soil dry weight after 14 days of exposure, whereas no mortalities were observed in the control and the test item concentrations 3.16 to 31.6 mg/kg soil dry weight. Consequently, the LC50 was determined to be 129 mg/kg soil dry weight.

The supporting study with edetic acid was also performed according to OECD guideline 207 using Eisenia fetida as test organism (Edwards et al. 2009). Concentrations between 0.1and 10000 mg/kg soil dw were tested in artificial soil over an exposure time of 14 days. Mortality was observed in the 100 and 316 mg/kg soil dw treatments. The 14d-LC50 is determined to be 156.46 mg/kg soil dw based on nominal concentrations.

Being the study of highest quality and showing the highest effects values, the key study was used to set a suitable NOEC value for the hazard assessment of Diammonium dihydrogen ethylenediaminetetraacetate (CAS 20824-56-0). No long-term toxicity data are considered to be needed, since the substance is biodegradable (in soil), not adsorptive and the respective conservative assessment factor was used for the environmental risk assessment.