L-Aspartic acid, N,N'-1,2-ethanediylbis-, sodium salt (1:3)

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial plants: long-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 208 (Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test)

Deviations:

yes

Remarks:

use of L. esculentum (tomato) in place of Brassica rapa (turnip)

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
no data

Analytical monitoring:

not required

Details on sampling:

- Concentrations: 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil
- Sampling method: no data
- Sample storage conditions before analysis: no data

Vehicle:

no

Details on preparation and application of test substrate:

- Method of application to filter paper (if used): not applicable
- Method of mixing into soil (if used): from each stock solution (for each species seperately) aliquots of 117.6 mL were added and thoroughly mixed with respectively about 3.03 g K2HPO4 and 1950 g of damp soil/sand mixture (the moisture content based on dry constituents was ca. 7.0% (911.2 grams of dry fine sand (0.5-1.0 mm), 911.2 g dry soil and 127.6 mL of water)).
- Method of application to soil surface (if used): no data
- Controls: the control was prepared in a similar way, however with demineralized water.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): demineralised water
- Concentration of vehicle in test medium (stock solution and final test solution): water was used as diluent
- Evaporation of vehicle before use: no data

Species:

Avena sativa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: oats
- Plant family: Poaceae
- Variety: Valiant
- Source of seed: CEBECO ZADEN B.V., (The Netherlands)
- Prior seed treatment/sterilization: no data
- Historical germination of seed (germination of seed lot tested): no data
- Seed storage: no data

Species:

Lactuca sativa

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: lettuce
- Plant family: Asteraceae
- Variety: Ravel RZ
- Source of seed: Rijk Zwaan (De Lier, The Netherlands)
- Prior seed treatment/sterilization: no data
- Historical germination of seed (germination of seed lot tested): no data
- Seed storage: no data

Species:

Lycopersicon esculentum

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: tomato
- Plant family: Solanaceae
- Variety: Spectra RZ
- Source of seed: Rijk Zwaan (De Lier, The Netherlands)
- Prior seed treatment/sterilization: no data
- Historical germination of seed (germination of seed lot tested): no data
- Seed storage: no data

Test type:

seed germination/root elongation toxicity test

Study type:

laboratory study

Substrate type:

other: semi natural soil

Limit test:

no

Total exposure duration:

18 d

Post exposure observation period:

no data

Test temperature:

22 +/- 3oC

pH:

5-7

Moisture:

400 g

Details on test conditions:

TEST SYSTEM
- Testing facility: TNO Nutrition and Food Research Institute, Schoemakerstraat 97, P.O. Box 6011, 2600 JA Delft, The Netherlands
- Test container (type, material, size): circular plastic containers (food quality) with a diameter of 9.3 cm and a height of 6.0 cm
- Amount of soil: 320 g of the dry soil
- No. of seeds per container: 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4
- No. of replicates per vehicle control: no data

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Geographic location: agricultural soil from an orchard in Heerewaarden (The Netherlands) and coarse sand (1:1)
- Pesticide use history at the collection site: no data
- Collection procedures: no data
- Sampling depth (cm): no data
- Soil texture (if natural soil)
- % sand: 79.8
- % silt: 13.4
- % clay: 0.8
- Soil taxonomic classification: no data
- Soil classification system: no data
- Composition (if artificial substrate): coarse sand (grain size 500 to 1000 urn)
- Organic carbon (%): 0.8
- Maximum water holding capacity (in % dry weight): no data
- CEC: no data
- Pretreatment of soil: a quantity of 1.66 g K2HPO4 was added per kg of dry soil
- Storage (condition, duration): no data

NUTRIENT MEDIUM (if used)
- Description: not used


GROWTH CONDITIONS
- Photoperiod: light-dark regime of 16 h light-8 h dark
- Light source: daylight lamps.
- Light intensity and quality: 6500: 1000 lux
- Day/night temperatures: 22 +/- 3oC
- Relative humidity (%): 49-85
- Wind velocity: no data
- Air exchange rate: no data
- Watering regime and schedules: no data
- Water source/type: no data
- Volume applied: no data
- Interval of applications: no data
- Method of application: no data
- Any pest control method/fertilization (if used): no data


ACCLIMATION PERIOD: no


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Emergence and survival - 18 days
Growth - 18 days
Visual appearance - 18 days
Effect on root growth - 18 days
- Phytotoxicity rating system (if used): not used


VEHICLE CONTROL PERFORMED: no


TEST CONCENTRATIONS
- Spacing factor for test concentrations: no data
- Justification for using less concentrations than requested by guideline: no data
- Range finding study
- Test concentrations: 1000 mg/kg of dry soil
- Results used to determine the conditions for the definitive study: yes

Nominal and measured concentrations:

0, 10, 32, 100, 320 and 1000 mg/kg of dry soil (nominal)

Reference substance (positive control):

not specified

Species:

Avena sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Species:

Lactuca sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Species:

Lycopersicon esculentum

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 320 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Species:

Avena sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: emergence and survival

Species:

Lactuca sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 320 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: emergence and survival

Species:

Lycopersicon esculentum

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: emergence and survival

Species:

Avena sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: condition (visual appearance)

Key result

Species:

Lactuca sativa

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 32 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: condition (visual appearance)

Species:

Lycopersicon esculentum

Duration:

18 d

Dose descriptor:

NOEC

Effect conc.:

ca. 100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: condition (visual appearance)

Details on results:

SEED GERMINATION
- Percent seed germination: no data
- Root length: no data (see root spread below)
- Root discolouration/malformation: no data
- Other effects (spread of roots):
- For A. sativa an effect on root growth (about 30% reduction in cover) was visually observed at 1000 mg/kg of dry soil.
- For L. sativa an effect on root growth was visually observed at 320 and 1000 mg/kg of dry soil (about 60 and 100% reduction in cover, respectively).
- For L. esculentum an effect on root growth (about 20% reduction in cover) was visually observed at 1000 mg/kg of dry soil.

- Results with reference substance valid? no data


SEEDLING EMERGENCE
- Percent seedling emergence:
- For A. sativa: 95%, 95%, 100%, 100%, 100% and 95% at 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil, respectively
- For L. sativa: 100% at all tested concentrations
- For L. esculentum: 90%, 80%, 85%, 80%, 95% and 85% at 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil, respectively

- Percent survival:
- For A. sativa: 100 % survival at all tested concentrations
- For L. sativa: 100%, 100%, 95%, 100%, 95% and 25% at 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil, respectively
- For L. esculentum: 100 % survival at all tested concentrations

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

Two tailed Dunnett-test

Table 2: pH measurements and illumination during the test.

Parameters	Time (days)	Measured at concentration (mg/kg dry soil)	A. sativa	L. sativa	L. esculentum
PH	0	0	7.2 7.3 7.2	7.3 7.2 7.3	7.3 7.3 7.3
	0	1000	7.3 7.4 7.4	7.4 7.3 7.4	7.4 7.4 7.4
PH	18	0	7.4 7.5 7.5	7.8 7.8 7.8	7.7 7.7 7.7
	18	320	7.7 7.7 7.7	-	-
	18	1000	7.9 7.9 7.9	7.8 7.8 7.8	7.8 7.8 7.8
light intensity (in lux) "	0		6650	6640	6470
	7		6620	6730	6690
	14		6350	6600	6790

Table 3: Results of the test with trisodium EDDS and the plant species A. sativa (oat), L. sativa (lettuce) and L. esculentum (tomato).

Parameter	Effect ^1)	Nominal concentration (mg/kg of dry soil) for species
		A. sativa	L. sativa	L. esculentum
18d LC50	emergence	>1000	>1000	>1000
18d NOEC	emergence	1000	320 2)	1000
18d NOEC	survival of seedlings	1000	320	1000
18d EC50	growth (wet weight)	>1000	219 (187 - 258)	833 (724 - 958)
18d NOEC	growth (wet weight)	1000	100	320
18d NOEC	condition	1000	32	100

1) The duration of plant growth after emergence was:

15 days for A. sativa (total test duration 18 days)

16 days for L. sativa (total test duration 18 days)

14 days for L. esculentum (total test duration 18 days)

2) Delayed emergence at day 2 and 3

Validity criteria fulfilled:

yes

Conclusions:

In a GLP study conducted according to OECD Guideline 208, the 18-d NOEC values for the growth of Avena sativa (oat), Lactuca sativa (lettuce) and Lycopersicon esculentum (tomato) was 1000, 100 and 320 mg trisodium EDDS/kg of dry soil, respectively. The corresponding 18-d NOECs for their condition (visual appearance) was 1000, 32 and 100 mg/kg of dry soil, respectively, and for their emergence and survival was 1000, 320 and 1000 mg/kg of dry soil, respectively.

Executive summary:

A GLP study was conducted, according to OECD Guideline 208, to determine the toxicity of trisodium EDDS to the plant species Avena sativa (oat), Lactuca sativa (lettuce) and Lycopersicon esculentum (tomato).

In the range-finding/limit test adverse effects were observed at 1000 mg per kg of dry soil .Therefore, in the main study five test concentrations of trisodium EDDS (i.e. 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil) were tested on 4 x 5 plants over 18 days. The plants were grown in a mixture of agricultural soil and coarse sand, supplemented with potassium and phosphorus to assess the emergence of the seedlings, survival of seedlings, and visual appearance and growth (wet-weight at the end of the test) of the plants.

Under the conditions of this study, the 18-d NOEC values for the growth of A. sativa, L. sativa and L. esculentum was 1000, 100 and 320 mg/kg of dry soil, respectively. The corresponding 18-d NOECs for their condition (visual appearance) were 1000, 32 and 100 mg/kg of dry soil, respectively, and for their emergence and survival were 1000, 320, 1000 mg/kg of dry soil, respectively.

Description of key information

In a GLP study conducted according to OECD Guideline 208, the 18-d NOEC values for the growth of Avena sativa, Lactuca sativa and Lycopersicon esculentum were 1000, 100 and 320 mg trisodium EDDS/kg of dry soil, respectively.

The corresponding 18-d NOECs for their condition (visual appearance) were 1000, 32 and 100 mg/kg of dry soil, respectively, and for their emergence and survival were 1000, 320, 1000 mg/kg of dry soil, respectively.

Key value for chemical safety assessment

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

32 mg/kg soil dw

Additional information

A GLP study was conducted, according to OECD Guideline 208, to determine the toxicity of trisodium EDDS to the plant species Avena sativa (oat), Lactuca sativa (lettuce) and Lycopersicon esculentum (tomato). In the main study, five test concentrations of trisodium EDDS (i.e. 0, 10, 32, 100, 320 and 1000 mg/kg of dry soil) were tested on 4 x 5 plants over 18 days. The plants were grown in a mixture of agricultural soil and coarse sand, supplemented with potassium and phosphorus to assess the emergence of the seedlings, survival of seedlings, and visual appearance and growth (wet-weight at the end of the test) of the plants. Under the conditions of this study, the 18-d NOEC values for the growth of A. sativa, L. sativa and L. esculentum was 1000, 100 and 320 mg/kg of dry soil, respectively. The corresponding 18-d NOECs for their condition (visual appearance) was 1000, 32 and 100 mg/kg of dry soil, respectively, and for their emergence and survival was 1000, 320 and 1000 mg/kg of dry soil, respectively (Henzen, 1999b).

The updated OECD Guideline 208 is designed to assess the potential effects of substances on seedling emergence and growth. Therefore, it is specific to a part of the plants life-cycle and does not cover chronic effects or effects on reproduction. However, it is assumed to cover a sensitive stage in the life-cycle of a plant and therefore data obtained from this study have been used in estimates of chronic toxicity.