cis-2-tert-butylcyclohexyl acetate

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

Study period:

Jan 2017 to Feb 2017

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)

Version / remarks:

July 19, 2006

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Remarks:

Test substance has been confirmed in the stock solution

Details on sampling:

Duplicat specimen of the homogenous stock solutions and the two spicemen of the matrix (acetone) as control were taken.

Vehicle:

yes

Remarks:

Aceton

Details on preparation and application of test substrate:

The test substance was dissolved in aceton and mixed with fine quartz sand before the test substance treated sand was mixed into the soil

Species:

Allium cepa

Plant group:

Monocotyledonae (monocots)

Species:

Avena sativa

Plant group:

Monocotyledonae (monocots)

Species:

Cucumis sativus

Plant group:

Dicotyledonae (dicots)

Species:

other: Solanum lycopersicum

Plant group:

Dicotyledonae (dicots)

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Species:

Brassica napus

Plant group:

Dicotyledonae (dicots)

Test type:

seedling emergence and seedling growth test

Study type:

laboratory study

Substrate type:

natural soil

Limit test:

no

Total exposure duration:

21 d

Remarks:

Fourteen to 21 days after 50% germination of the control

Post exposure observation period:

No

Test temperature:

21

pH:

5.9

Moisture:

65

Nominal and measured concentrations:

Nominal concentration were used

Reference substance (positive control):

no

Key result

Species:

other: Plant average

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

44 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Remarks on result:

other: EC10 average

Remarks:

Number of species >=5

Species:

Brassica napus

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

48.2 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

growth

Species:

Glycine max (G. soja)

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

33.2 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

growth

Species:

other: Solanum lycopersicum

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

17.2 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

growth

Species:

Cucumis sativus

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

92 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

growth

Species:

Avena sativa

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

67.7 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

growth

Species:

Allium cepa

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

10.9 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth

Reported statistics and error estimates:

Statistical analysis of the control plants and solvent control plants:
Update for the test substance
Fresh weight data were tested for normal distribution and homogeneity of variance (F test, a = 0.05). If the data were normally distributed and homogeneous the Student t-test (pairwise comparison, two-sided, a = 0.05) was used. If the data were not normally distributed the Mann-Whitney U-test (pairwise comparison, two-sided, a = 0.05) was used.

 

 

Validity criteria fulfilled:

yes

Remarks:

Germination Rate of the Control Seeds wat at least 70%; Mean Survival of Emerged Control Seedlings was > 90%; the control seedlings did not exhibit phytotoxic effects.

Conclusions:

The EC10 of 44 mg/kg soil dw will be used for the CSA, which is an average EC10 over 6 plant species.

Executive summary:

In a terrestrial plant test according to OECD TG 208 under GLP, 6 plant species were tested for seedling emergence, growth and phytotoxic effects (chlorosis, necrosis and abnormal growth). The soil is a sandy loam and was sterilised before use. All particles were < 0.2cm. The organic matter content is 0.67 +/-0.03% and the pH was 5.9 +/-0.6. The substance was mixed with quarts sand and thereafter mixed into the soil. The following dicotyles were used: Brassica napus, Glycine max, Solanum lycopersicum and Cucumis sativus. The following monocotyles were use: Avena sativa and Allium cepa. Doses were selected based on a dose range finding study and were 12.3, 37, 111, 333 and 1000 mg/kg soil dw for most species. Two additional concentrations were used for Brassica napus and Glycine max: 1.37 and 4.12 mg/kg dw soil. One additional concentration was used for Solanum lycopersicum: 4.12 mg/kg dw soil. The concentration in the stock solution was verified but actual measures in the soil were not performed. Untreated seeds were sewn in pots and plants were grown for 14 days, except Allium cepa which was grown for 21 days. Fresh weight of the leaves of plants was the more sensitive endpoint compared to germination, phytotoxicity and mortality. The EC10 of all six plant species was averaged as the number of species =>5. The overall EC10 on leaf fresh weight being the most sensitive parameter resulted in 44 mg/kg soil dw based on nominal values and being the average of 6 plant species based on nominal values.

Description of key information

In a terrestrial plant test according to OECD TG 208 under GLP, 6 plant species were tested for seedling emergence, growth and phytotoxic effects (chlorosis, necrosis and abnormal growth). The test concentrations were verified in the stock solutions. The substance was mixed with quarts sand and thereafter mixed into the soil. The following dicotyles were used: Brassica napus, Glycine max, Solanum lycopersicum and Cucumis sativus. The following monocotyles were use: Avena sativa and Allium cepa. Doses were selected based on a dose range finding study and were 12.3, 37, 111, 333 and 1000 mg/kg soil dw for most species. Two additional concentrations were used for Brassica napus and Glycine max: 1.37 and 4.12 mg/kg dw soil. One additional concentration was used for Solanum lycopersicum: 4.12 mg/kg dw soil. The concentration in the stock solution was verified but actual measures in the soil were not performed. The soil is a sandy loam and was sterilised before use. All particles were < 0.2cm. The organic matter content is 0.67 +/- 0.03 % and the pH was 5.9 +/- 0.6. Untreated seeds were sewn in pots and plants were grown for 14 days, except Allium cepa which was grown for 21 days. Fresh weight of the leaves of plants was the more sensitive endpoint compared to germination, phytotoxicity and mortality. The EC10 of all six plant species was averaged as the number of species ≥ 5. The overall EC10 on leaf fresh weight being the most sensitive parameter resulted in 44 mg/kg soil dw being the average of 6 plant species.

Key value for chemical safety assessment

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

44 mg/kg soil dw