Alkanes, C16-47, branched and linear

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial plants: long-term

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Species:

Glycine max (G. soja)

Duration:

22 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

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Glycine max (G. soja)

Duration:

22 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

seedling emergence

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Lycopersicon esculentum

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

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Lycopersicon esculentum

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

seedling emergence

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Sinapis alba

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:

germination

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Sinapis alba

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

seedling emergence

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Avena sativa

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

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Avena sativa

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

seedling emergence

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Lolium perenne

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

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Key result

Species:

Lolium perenne

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

seedling emergence

Remarks:

and growth based on final dry weight

Remarks on result:

other: 95 % CL Not stated

Details on results:

RESULTS
Range-finding Test
A summary of the percentage emergence and mortality for each species during the range-finding test is given in Table 2 - see in attached section.
No morphological effects were observed throughout the duration of the test.

Statistical analysis using Bartlett's test for homogeneity of variance (Sokal and Rohlf 1981) and Dunnett's multiple comparison procedure for comparing several treatments with a control (Dunnett 1955) was carried out on the emergence and shoot dry weight data for each species.

There were no significant differences (P<0.05) between the control and all the test groups in terms of emergence for each species.
There were no significant decreases in shoot dry weight (P<0.05) between the control and all the test groups at test termination for oat, perennial ryegrass, tomato and mustard.

A significant decrease in shoot dry weight (P<0.05) was observed between the control and the 100 mg/kg test group at test termination for soybean. A review of the data indicated that this result was probably due to a single seedling which showed a greatly reduced weight compared to the remainder of the seedlings. It was therefore considered that this single value may have skewed the analysis. Given that no significant decrease in shoot dry weight was observed between the control and 1000 mg/kg test concentration, this was considered not to affect the outcome of the study.
For perennial ryegrass and mustard a significant increase in shoot dry weight was observed between the control and the 100 and 1000 mg/kg test concentrations respectively. This was considered not to affect the outcome of the test as the effect observed was not a reduction in weight.
Based on this information, test concentration of 100, 180, 320, 560 and 1000 mg/kg were selected for each species for the definitive test.

Definitive Test
Emergence Data
Soybean (Glycine max), tomato (Lycoperisicon esculentum), mustard (Sinapis alba), oat (Avena sativa) and perennial ryegrass (Lolium perenne) reached 50% emergence in the control on Days 9, 10, 4, 5 and 7 after sowing respectively.
A summary of the percentage emergence for each species are given in Tables 3 to 7 - see in attached section

Statistical analysis using Bartlett's test for homogeneity of variance (Sokal and Rohlf 1981) and Dunnett's multiple comparison procedure for comparing several treatments with a control (Dunnett 1955) was carried out on the emergence data for each species.

There were no significant differences (P<0.05) between the control and all the test groups in terms of emergence for each species.
Inspection of the emergence data based on the nominal test concentrations gave the following results:

Species EC50 (emergence) (mg/kg)
Soybean >1000
Tomato >1000
Mustard >1000
Oat >1000
Perennial Ryegrass >1000

The No Observed Effect Concentration for each species was 1000 mg/kg. The No Observed Effect Concentration is based upon no significant differences (P<0.05) between the test concentrations and the control.

Morphological Effects
A summary of the percentage mortality, for each species is given in Table 8 - see in attached section

No morphological abnormalities were observed for each species throughout the test.

Shoot Dry Weight Data
Shoot mean dry weight values for each species are given in Tables 9 to 13 - see in attached section.

Individual values for shoot dry weights are given in Appendix 1 - see in attached section

Statistical analysis using Bartlett's test for homogeneity of variance (Sokal and Rohlf 1981) and Dunnett's multiple comparison procedure for comparing several treatments with a control (Dunnett 1955) was carried out on the shoot dry weight data for each species.
There was no significant decrease in shoot dry weight (P<0.05) between the control and all the test groups in terms of shoot dry weights at test termination for all test species.

A significant increase in shoot dry weight was observed at test concentrations of 180 and 320 mg/kg for perennial ryegrass and 560 and 1000 mg/kg for mustard. Given that the effect observed was not a detrimental effect, this was considered not to affect the outcome of the study.
Inspection of the shoot dry weight data based on the nominal test concentrations gave the following results:

Species EC50 (growth) (mg/kg)
Soybean >1000
Tomato >1000
Mustard >1000
Oat >1000
Perennial Ryegrass >1000

The No Observed Effect Concentration for each species was 1000 mg/kg. The No Observed Effect Concentration is based upon no significant differences (P<0.05) between the test concentrations and the control.

Physico-chemical measurements
The temperature was maintained at 7 degree C to 37 degree C and the relative humidity at 20% to 89% with a photoperiod of approximately 16 hours light and 8 hours darkness.

Some of the temperatures were observed to be outside the range given in the study plan. This deviation was considered not to affect the integrity or the outcome of the study as no morphological abnormalities were observed in the control plants.

CONCLUSION
The EC50 (emergence) and EC50 (growth based on final dry weight) for the test item based on nominal test concentrations for the five species tested were as follows:
Species EC50 (emergence) (mg/kg) No Observed Effect Concentration (mg/kg) EC50
(growth) (mg/kg) No Observed Effect Concentration (mg/kg)
Soybean >1000 1000 >1000 1000
Tomato >1000 1000 >1000 1000
Mustard >1000 1000 >1000 1000
Oat >1000 1000 >1000 1000
Perennial Ryegrass >1000 1000 >1000 1000

Reported statistics and error estimates:

Statistical analysis of the emergence and dry weight data for each species was performed using Bartlett's test for homogeneity of variance (Sokal and Rohlf 1981) and Dunnett's multiple comparison procedure for comparing several treatments with a control (Dunnett 1955). All statistical analyses were performed using the SAS computer software package (SAS 1999 - 2001).

Due to the nature and quantity of the tables, all tables have been attached (see "Attached background material").

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (emergence) and EC50 (growth based on final dry weight) for the read across substance GTL Base Oil Distillates based on nominal test concentrations for the five species tested were as follows:

Species EC50 (emergence)(mg/kg) No Observed Effect Concentration EC50 (growth) mg/kg) No Observed Effect Conecentration (mg/kg) (mg/kg)

Soybean >1000 1000 >1000 1000
Tomato >1000 1000 >1000 1000
Mustard >1000 1000 >1000 1000
Oat >1000 1000 >1000 1000
Perennial Ryegrass >1000 1000 >1000 1000

Executive summary:

Introduction.

A study was performed to assess the effects of the test item on the emergence and growth of five plant species. The method followed that described in the OECD Guidelines for the Testing of Chemicals: Guideline 208: Terrestrial (Non-target) Plant Test: Seedling Emergence and Seedling Growth Test (July 2006).

Methods.

Following a preliminary range-finding test, five plant species; three dicotyledonous species, soybean (Glycine max), tomato (Lycopersicon esulentum) and mustard (Sinapis alba) and two monocotyledonous species, oat (Avena sativa) and perennial ryegrass (Lolium perenne) were exposed to concentrations of 100, 180, 320, 560 and 1000 mg/kg. The number of seedlings emerged and any mortalities and/or morphological abnormalities were determined daily for 21 or 22 days after 50% emergence in the control for each species.

Results.

The EC₅₀(emergence) and EC₅₀(growth based on final dry weight) for the read across substance based on nominal test concentrations for the five species tested were as follows:

Species	EC50(emergence) (mg/kg)	No Observed Effect Concentration (mg/kg)	EC50 (growth) (mg/kg)	No Observed Effect Concentration (mg/kg)[1]
Soybean	>1000	1000	>1000	1000
Tomato	>1000	1000	>1000	1000
Mustard	>1000	1000	>1000	1000
Oat	>1000	1000	>1000	1000
Perennial Ryegrass	>1000	1000	>1000	1000

[*]No Observed Effect Concentration (growth) based on the concentration where no significant decrease was observed for dry weight compared to the control and no morphological abnormalities were observed

Description of key information

Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test (OECD Guideline 208):
- Glyicine max: NOEC (22 d): >= 1000 mg/kg soil dw test mat. (nominal) based on: emergence, growth and mortality
- Glyicine max: EC50 (22 d): >1000 mg/kg soil dw test mat. (nominal) based on: emergence, growth and mortality
- Lycopersicon esulentum, Sinapis alba, Avena sativa, Lollium perenne: NOEC (21 d): >= 1000 mg/kg soil dw test mat. (nominal) based on: emergence, growth and mortality
- Lycopersicon esulentum, Sinapis alba, Avena sativa, Lollium perenne: EC50 (21 d): >1000 mg/kg soil dw test mat. (nominal) based on: emergence, growth and mortality

Additional information

Five plant species; three dicotyledonous species, soybean (Glyicine max), tomato (Lycopersicon esulentum) and mustard (Sinapis alba) and two monocotyledonous species, oat (Avena sativa) and perennial ryegrass (Lolium perenne) were exposed to concentrations of 100, 180, 320, 560 and 1000 mg/kg dw of the read across substance GTL Base Oil Distillates in a seedling emergence and growth test. The study was conducted according to OECD 208 and to GLP, however no analytical monitoring was carried out.

The number of seedlings which emerged, mortalities and morphological abnormalities were recorded daily for 21 or 22 days after 50% emergence in the controls for each species. It was not possible to establish an EC₅₀with these species and NOEC values have been reported to be at least 1000 mg/kg dw for all the organisms tested and across all endpoints.