Registration Dossier

Administrative data

Endpoint:
toxicity to terrestrial plants: short-term
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report date:
2016

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 208 (Terrestrial Plants, Growth Test)
Deviations:
no
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
2-butoxyethyl benzoate
EC Number:
226-685-8
EC Name:
2-butoxyethyl benzoate
Cas Number:
5451-76-3
Molecular formula:
C13H18O3
IUPAC Name:
2-butoxyethyl benzoate
Test material form:
other: liquid
Details on test material:
2-Butoxyethyl benzoate, Lot # 201303443-19; Purity 99.2 %
Specific details on test material used for the study:
2-Butoxyethyl Benzoate (Lot Number 201303443-19)

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
After preparation of dosing stocks, 10 mL samples were collected to verify test concentration and to demonstrate homogeneity of the test substance in the dosing solutions. A single sample was collected from the negative control, the solvent control, and the lower four test level dosing stocks. Triplicate samples were collected from the high level dosing stock. Following collection, samples were transferred to the analytical chemistry laboratory for analysis.

Test substrate

Vehicle:
yes
Remarks:
acetonitrile
Details on preparation and application of test substrate:
Test soils were prepared by mixing stock solutions of the test substance into 40 kg fresh weight of soil. A primary stock was prepared by adding 75.1020 g of the test substance to 1000 mL of acetonitrile and mixing by swirling, inversion and stirring. The primary stock concentration was based on a mean, measured soil moisture content of 8%, and a volume of 490 mL to be used for soil preparation. Secondary stocks were prepared by diluting 31.3, 62.5, 125 and 250 mL aliquots of the primary stock, each to a final volume of 500 mL with acetonitrile, and mixing by stirring, swirling, and inversion. The solvent control stock consisted of acetonitrile only, and the negative control stock consisted of well water purified by reverse osmosis. In order to prepare test soils, 490 mL of eachstock was added to 40 kg of bulk soil, mixed in a soil mixer for approximately 10 minutes, turned by hand, and then mixed for another approximately 10 minute period. The negative control was prepared first, followed by the solvent control, and then the test soils in order of increasing concentration to avoid cross-contamination of the test material.

Test organisms

open allclose all
Species:
Glycine max (G. soja)
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Glycine max (soybean) Viking 2265
Fabaceae
Johnny’s Selected Seeds, Winslow, ME USA
88
Species:
Zea mays
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
Zea mays (corn) Nothstine Dent OG
Poaceae
Johnny’s Selected Seeds, Winslow, ME USA
98

Study design

Test type:
seedling emergence and seedling growth test
Study type:
laboratory study
Substrate type:
natural soil
Limit test:
no
Total exposure duration:
21 d

Test conditions

Nominal and measured concentrations:
63, 125, 250, 500 and 1000 milligrams test substance per kilogram of soil dry weight (mg/kg). Measured concentrations were within 99 - 101% of nominal.

Results and discussion

Effect concentrationsopen allclose all
Key result
Species:
Glycine max (G. soja)
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
> 1 000 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
seedling emergence
Key result
Species:
Glycine max (G. soja)
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
250 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth
Key result
Species:
Zea mays
Duration:
21 d
Dose descriptor:
EC50
Effect conc.:
> 1 000 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
seedling emergence
Key result
Species:
Zea mays
Duration:
21 d
Dose descriptor:
NOEC
Effect conc.:
500 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth
Details on results:
Test soil concentrations of up to 1000 mg/kg dry soil resulted in no adverse effects on the seedling emergence or survival of either Z. mays or G. max. There were adverse effects on height and dry weight of both Z. mays and G. max at the highest treatment levels. The NOEC and LOEC for Z. mays (corn) were 500 and 1000 mg/kg dry soil respectively for both dry weight and height. The NOEC and LOEC for G. max (soybean) were 250 and 500 mg/kg dry soil respectively for both dry weight and height.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Executive summary:

Test soil concentrations of up to 1000 mg/kg dry soil resulted in no adverse effects on the seedling emergence or survival of either Z. mays or G. max. There were adverse effects on height and dry weight of both Z. mays and G. max at the highest treatment levels. The NOEC and LOEC for Z. mays (corn) were 500 and 1000 mg/kg dry soil respectively for both dry weight and height. The NOEC and LOEC for G. max (soybean) were 250 and 500 mg/kg dry soil respectively for both dry weight and height.