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Ecotoxicological information

Toxicity to terrestrial plants

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Administrative data

Endpoint:
toxicity to terrestrial plants: long-term
Type of information:
experimental study
Adequacy of study:
key study
Study period:
no data available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
2006
Report date:
2006

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 227 (Terrestrial Plant Test: Vegetative Vigour Test)
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
Disodium dihydrogen ethylenediaminetetraacetate
EC Number:
205-358-3
EC Name:
Disodium dihydrogen ethylenediaminetetraacetate
Cas Number:
139-33-3
Molecular formula:
C10H14N2Na2O8
IUPAC Name:
disodium dihydrogen 2,2',2'',2'''-(ethane-1,2-diyldinitrilo)tetraacetate
Test material form:
solid

Sampling and analysis

Analytical monitoring:
not specified

Test substrate

Vehicle:
no
Details on preparation and application of test substrate:
A silty–loamy sand agricultural soil, USDA (Soil Survey Manual), was collected from 0 to 30 cm surface layer of the Melaten field in Aachen, Germany. The soil was air-dried at room temperature, sieved through a 2-mm sieve and characterised as follows:

pH: 6.8
organic matter: 3.5 %
soil fractions
sand: 49.4 %
Clay: 42.1 %
Silt: 8.5 %

Test organisms

Species:
other: Nicotiana tabacum
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Tobacco plants (N. tabacum SR-1) were used for the experiment.

Study design

Test type:
vegetative vigour test
Study type:
laboratory study
Substrate type:
natural soil
Limit test:
no
Total exposure duration:
21 d
Remarks:
approximately 3 weeks
Post exposure observation period:
no data available

Test conditions

Test temperature:
25/20 °C light/dark temperature regime
pH:
6.40 - 6.83
Moisture:
60% relative humidity
Details on test conditions:
16 h light period (light intensity of 320 µmol/m2 * s)
Nominal and measured concentrations:
Nominal: 0.125,0.25, 1.25, 62.5, 125, and 250 mmol/kg for Na2EDTA
Reference substance (positive control):
not specified

Results and discussion

Effect concentrationsopen allclose all
Key result
Species:
other: Nicotiana tabacum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
>= 84 - < 420 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth
Key result
Species:
other: Nicotiana tabacum
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
>= 0.25 - < 1.25 other: mmol/kg
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth
Details on results:
EDTA did not show any adverse effects at a concentration of < 0.125 mmol/kg. At 1.25 mmol/kg of EDTA the leaves showed necrotic lesions and the dry weight was negligible. At a concentration of 0.25 mmol/kg EDTA the dry weight is only slightly lower but the standard deviation is higher in comparison to the 0.125 mmol/kg application.
Results with reference substance (positive control):
no data available
Reported statistics and error estimates:
no data availble

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Conclusions:
Based on the results of this vegetative vigour study EDTA had an inhibitory effect on growth of Nicotiana tabacum at rate of 1.25 mmol/kg soil (equivalent to 420 mg/kg). The NOEC will be determined to be 0.25 mmol/kg soil (equivalent to 84 mg/kg soil).
Executive summary:

The effects of EDTA (Na2EDTA) on vegetative vigour of plants following application were examined in a laboratory test on Nicotiana tabacum. The test item was applied at a dose rate of up to 250 mmol/kg and compared to an untreated control.

According to the results, the test item had an inhibitory effect on growth of the tested species at rates of 1.25 mmol/kg soil (equivalent to 420 mg/kg) and thus determined to be the overall LOEC for this species.

The overall NOEC was determined to be 0.25 mmol/kg soil (equivalent to 84 mg/kg).