Ethylene dibenzoate

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial plants: short-term

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of the soil compartment is unlikely

Reference 2

Endpoint:

toxicity to terrestrial plants: short-term

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Study performed according to MEP 299 guideline, a Chinese standard using industrial sand instead of soil. Endpoints are expressed in mg/L and are therefore difficult to compare to standard endpoints which are in mg/kg soil.

Qualifier:

according to guideline

Guideline:

other: MEP 299 “Seed Germination/Root Elongation Toxicity Test”. China Environmental Press, 2013.8.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Chemical name Ethylene glycol dibenzoate
CAS No.: 94—49-5
Chemical formula: C16H1404
Supplier of Test Item : TCI (Shanghai) Development Co., Ltd.
Batch number: FCZ01
Appearance: White crystalline powder
Purity: 99.7%
Re-certification date: 2024-12-31

Vehicle:

no

Species:

other: Amaranthus sp.

Plant group:

Dicotyledonae (dicots)

Species:

Lolium perenne

Plant group:

Monocotyledonae (monocots)

Species:

Lycopersicon esculentum

Plant group:

Dicotyledonae (dicots)

Species:

Lepidum sativum

Plant group:

Dicotyledonae (dicots)

Species:

other: Medicago sativa

Plant group:

Dicotyledonae (dicots)

Species:

Zea mays

Plant group:

Monocotyledonae (monocots)

Species:

Triticum aestivum

Plant group:

Monocotyledonae (monocots)

Species:

Cucumis sativus

Plant group:

Dicotyledonae (dicots)

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Species:

other: Vigna radiata (mung bean)

Plant group:

Dicotyledonae (dicots)

Test type:

seed germination/root elongation toxicity test

Study type:

laboratory study

Substrate type:

other: Industrial sand (fine quartz sand was dominant with more than 50% of the particles between 50 and 200 microns, about 200g/per vessel).

Limit test:

no

Total exposure duration:

5 d

Remarks:

The test period was ended when at least 65 percent of the control seed had
germinated and developed roots that were at least 20 mm long.

Test temperature:

24.3-25.8 °C

pH:

7.48 -7.59

Moisture:

4.3 - 9.4%

Details on test conditions:

Weights of 0.01920, 0.03842, 0.07560, 0.15010, 0.30071 and 0.60018 g of test item were dissolved with 60 mL acetone to obtain a test item solution of 320, 640,1260, 2500, 5000 and 10000 mg/L respectively, a weight of 4.00037 g of test item was dissolved with 200 mL acetone to obtain a test item solution of 20000 mg/L.
5.00 mL of each acetone solution of test item was mixed manually with about 200 g of industrial sand in the dish and the acetone was allowed to evaporate completely at room temperature for about 3 hours. Then 100 mL of distilled water was added to the dish and mixed with the treated sand. The test concentrations in the dish were 16, 32, 63, 125, 250, 500 and 1000 mg/L. 5.00 mL acetone was treated as the test group and used as an acetone (solvent) control. 100 mL of distilled water was added and mixed with about 200 g of industrial sand in the dish and used as a blank control.
Blank control group, acetone control group and 1000 mg/L test group were
prepared with 3 replicates respectively for each seed (in total 30 replicates), and 16, 32, 63, 125, 250, 500 mg/L test group were prepared with 3 replicates respectively for Soy bean, Garden cress and Tomato (in total 9 replicates), and 1 additional replicate of each group was prepared to analyze the concentration of test item.

Nominal and measured concentrations:

Nominal:
Common wheat, Mung bean, Cucumber, Corn, Alfalfa, Bonus
amaranth and Ryegrass, the definitive test was carried out as a limit test of 1000 mg/L.
For Soy bean, Garden cress and Tomato, the definitive test was carried out at 7 concentrations of 16, 32, 63, 125, 250, 500 and 1000 mg/L.

Measured initial concentrations:
15.0, 30.2, 59.6, 116.7, 229.5, 461.0 and 946.0 mg/L

Reference substance (positive control):

no

Species:

Lepidum sativum

Duration:

5 d

Dose descriptor:

NOEC

Effect conc.:

63 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

germination

Species:

Lepidum sativum

Duration:

5 d

Dose descriptor:

EC50

Effect conc.:

2 344 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

germination

Remarks on result:

other: extrapolated

Species:

Glycine max (G. soja)

Duration:

5 d

Dose descriptor:

NOEC

Effect conc.:

16 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

germination

Key result

Species:

Glycine max (G. soja)

Duration:

5 d

Dose descriptor:

EC50

Effect conc.:

513 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

germination

Species:

Lepidum sativum

Duration:

5 d

Dose descriptor:

NOEC

Effect conc.:

16 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: root elongation

Species:

Lepidum sativum

Duration:

5 d

Dose descriptor:

EC50

Effect conc.:

2 089 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: root elongation

Remarks on result:

other: extrapolated

Species:

Glycine max (G. soja)

Duration:

5 d

Dose descriptor:

NOEC

Effect conc.:

63 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: root elongation

Key result

Species:

Glycine max (G. soja)

Duration:

5 d

Dose descriptor:

EC50

Effect conc.:

513 other: mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: root elongation

Details on results:

All other species did not show effects at the limit/highest test concentration of 1000 mg/L.

Reported statistics and error estimates:

Two-sided Student t—test in Microsot Office Excel 2007 was employed to compare the differences between the blank control group and the acetone (solvent) control, there was no significant difference (p>0.05). Therefore, the effect differences of the treatment group for each plant species were compared with the blank control group, Two-sided Student t—test in Microsoft Office Excel 2007 was employed.
Probit method was used to derive the EC10 and EC50 value and the corresponding 95% confidence limit.

Conclusions:

For most plant species the test substance did not give any effect up to the highest test concentration of 1000 mg/L.
For Soy bean the EC50 value for germination and root elongation was 513 mg/L.
Ethylene glycol dibenzoate can therefore be considered as not acutely toxic to terrestrial plants.

Executive summary:

A seed germination/root elongation toxicity test with Ethylene glycol dibenzoate was conducted with 1 0 kinds of seeds.
Based on the results of a preliminary test, for Common wheat, Mung bean, Cucumber, Corn, Alfalfa, Bonus amaranth and Ryegrass, the definitive test was carried out as a limit test of 1000 mg/L, for Soy bean, Garden cress and Tomato, the definitive test was carried out at 7 concentrations of 16, 32, 63, 125, 250, 500 and 1000 mg/L. An acetone (solvent) control and a blank control group were performed concurrently. Each plant was exposed to the controls and respective test concentrations, 3 replicates were included in the controls and test groups, 10 seedswere used in each treatment.
The matrix was 200 g industrial sand and 100 mL test solution. After the seeds were exposed to the test solutions, the glass Petri dishes was incubated in the temperature-controlled room (252t1 °C) and in the dark.
The concentrations were determined in samples of test media by HPLC. 1 additional replicate of each group was prepared to analyze the concentration of test item. For the nominal concentrations of 16, 32, 63, 125, 250, 500 and 1000 mg/L, the initial measured concentrations were 91.8% - 94.6% of nominal concentrations.
The number of seeds that germinated was counted and root lengths were measured for each test species when at least 6 5 percent of the control seed had germinated and developed roots that were at least 20 mm long.
According the test results, the effective concentrations for germination of seed and root elongation for the most sensitive species tested are as follows, based on the nominal concentrations:

Soy bean

Seed germination: NOEC =  16 mg/L; EC50 = 513 mg/L

Root elongation: NOEC = 63 mg/L; EC50 = 513 mg/L

 

Description of key information

Even though the study can be waived a Seed germination and Root elongation study was performed according to the Chinese Guideline MEP 299 in China. Even though this study is not performed according to a standard accepted guideline under EU REACH it shows that Ethylene glycol dibenzoate is not acutely toxic to terrestrial plants.