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Ecotoxicological information

Toxicity to terrestrial plants

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Administrative data

Endpoint:
toxicity to terrestrial plants: long-term
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 1990-04-25 to 1990-06-05
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report Date:
1991

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: OECD guideline 208 "Terrestrial Plants, Growth Test", adopted 4 April 1984
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Name of test material (as cited in study report): Marlotherm S
- Substance type: pure active substance
- Physical state: yellow liquid
- Lot/batch No.: 200 l barrel from August 21, 1991
- Stability under test conditions: unlimited
- Storage condition of test material: no data
Specific details on test material used for the study:
The purity of the material used for the test was lower than the purity of the actual material. It contained ca. 26% of isomers of dimethyl tribenzenes. However, based on comparable basic structure of the impurities and the assumption that any toxic effects would increase with higher molecular weight and lipophilicity, we regard that the studies conducted with the lower purity material being "worst case" and can be used for the evaluation of the actual product.

Sampling and analysis

Analytical monitoring:
no

Test substrate

Vehicle:
no
Details on preparation and application of test substrate:
- Method of mixing into soil: 1, 10 and 100 mg of test substance were mixed with 1000 g soil
- Controls: soil without test substance

Test organisms

open allclose all
Species:
Triticum aestivum
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
- Common name: wheat
- Plant family: Poaceae
- Variety: not mentioned
- Source of seed: not mentioned
- Prior seed treatment/sterilization: not mentioned
- Historical germination of seed (germination of seed lot tested): not tested
- Seed storage: not mentioned
Species:
Raphanus sativus
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
- Common name: fenugreek
- Plant family: Brassicaceae
- Variety: not mentioned
- Source of seed: not mentioned
- Prior seed treatment/sterilization: not mentioned
- Historical germination of seed (germination of seed lot tested): ot tested
- Seed storage: not mentioned
Species:
Trifolium ornithopodioides
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
- Common name: garden cress
- Plant family: Faboideae
- Variety: not mentioned
- Source of seed: not mentioned
- Prior seed treatment/sterilization: not mentioned
- Historical germination of seed (germination of seed lot tested): ot tested
- Seed storage: not mentioned

Study design

Test type:
seedling emergence toxicity test
Study type:
laboratory study
Substrate type:
artificial soil
Limit test:
no
Total exposure duration:
20 d
Post exposure observation period:
none

Test conditions

Test temperature:
22 - 24 °C
pH:
7.3 - 7.5
Moisture:
approx. 25 % , no further details mentioned
Details on test conditions:
TEST SYSTEM
- Testing facility: partly air-conditioned room, no further details mentioned
- Test container (type, material, size): flowerpots of black plastics (diameter top/bottom approx. 8/6 cm; height approx. 9-10 cm)
- Amount of soil: 100 g test substrate per planting pot
- Method of seeding: not mentioned
- No. of seeds per container: 5
- No. of plants (retained after thinning): no thinning performed
- No. of replicates per treatment group: 20 (for each plant species 4 replicates with 5 seeds each)
- No. of replicates per control: 20 (4 replicates with 5 seeds each)

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Composition (if artificial substrate): corresponded to the requirements of the guideline, no further details mentioned
- Organic carbon (%): 0.18 %
- Maximum water holding capacity (in % dry weigth): approx. 25 %
- CEC: not mentioned
- Pretreatment of soil: sieved with 0.5 cm mesh, no further details mentioned
- Storage (condition, duration): not mentioned

NUTRIENT MEDIUM: not used

GROWTH CONDITIONS
- Photoperiod: 16 h light, 8 h darkness
- Light source: not mentioned
- Light intensity and quality: seeding phase: 10 h at 200 Lux, 14 h darkness; growth phase: 10 h at 11 000 Lux, 14 h darkness
- Day/night temperatures: 21 - 25 °C, not differentiated between day and night
- Relative humidity (%): not mentioned
- Wind velocity: not applicable
- Air exchange rate: not mentioned
- Watering regime and schedules:
- Water source/type: not mentioned
- Volume applied: not mentioned
- Interval of applications: once during the test
- Method of application: not mentioned
- Any pest control method/fertilization (if used): not used

ACCLIMATION PERIOD: not mentioned

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : emergence of seeds, weight of overground part of plant at the end of the test

- Phytotoxicity rating system (if used): not used
Nominal and measured concentrations:
1, 10 and 100 mg/kg soil (nominal), dry weight
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Key result
Species:
Triticum aestivum
Duration:
19 d
Dose descriptor:
LC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
seedling emergence
Key result
Species:
Triticum aestivum
Duration:
19 d
Dose descriptor:
EC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth
Key result
Species:
Raphanus sativus
Duration:
20 d
Dose descriptor:
LC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
seedling emergence
Key result
Species:
Raphanus sativus
Duration:
20 d
Dose descriptor:
EC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth
Key result
Species:
Trifolium ornithopodioides
Duration:
20 d
Dose descriptor:
LC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
seedling emergence
Key result
Species:
Trifolium ornithopodioides
Duration:
20 d
Dose descriptor:
EC50
Effect conc.:
> 100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
growth
Key result
Species:
Triticum aestivum
Duration:
19 d
Dose descriptor:
NOEC
Effect conc.:
100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: Seedling emergence and growth
Key result
Species:
Raphanus sativus
Duration:
20 d
Dose descriptor:
NOEC
Effect conc.:
100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: seedling emergence and growth
Key result
Species:
Trifolium ornithopodioides
Duration:
20 d
Dose descriptor:
NOEC
Effect conc.:
100 mg/kg soil dw
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
other: seedling emergence and growth
Details on results:
SEEDLING EMERGENCE
- Percent seedling emergence: see below (remarks on results)
- Percent survival: see below (remarks on results)
- Plant height: not measured
- Dry weight: not measured, fresh weight was measured: see below
- Abnormal seed development or appearance: not determined
- Other effects: none mentioned
Results with reference substance (positive control):
no reference substance tested
Reported statistics and error estimates:
not mentioned

Any other information on results incl. tables

- Effect data: Wheat

- Nominal concentrations: 1, 10, 100 mg/kg dry soil

- Effect data:

- Emergence: 100 % / 95 % / 95 %

- Plant growth: 147.4 ± 39.1 mg / 132.6 ± 31.3 mg / 109.2 ± 39.5 mg

RESULTS CONTROL:

- Emergence: 100 %

- Plant growth: 121.2 ± 37.6 mg

- Effect data: Radish

- Nominal concentrations: 1, 10, 100 mg/kg dry soil

- Effect data:

- Emergence: 100 % / 100 % / 96 %

- Plant growth: 219.4 ± 52.7 mg / 282.8 ± 88.8 mg / 283.2 ± 117.2 mg

RESULTS CONTROL:

- Emergence: 96 %

- Plant growth: 152.6 ± 50.7 mg

- Effect data: Fenucreek

- Nominal concentrations: 1 / 10 / 100 mg/kg dry soil

- Effect data:

- Emergence: 96 % / 76 % / 92 %

- Plant growth: 112.9 ± 32.9 mg / 114.6 ± 29.1 mg / 110.4 ± 29.6 mg

RESULTS CONTROL:

- Emergence: 88 %

- Plant growth: 107.9 ± 29.6 mg

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Not phytotoxic under test conditons at concentrations up to a concentration of 100 mg/kg dry soil.
Executive summary:

The test item Marlotherm S was tested on effects of seedling emergence and seedling growth on three non-target plant species representing three plant families according to OECD Guideline for Testing of Chemicals No. 208 (from 4 April 1984).

For the test the following plant species were selected: wheat (Triticum aestivum) for Category 1, radish (raphanus sativus) for Category 2 and fenucreek (trifolium ornithopadioides) for Category 3. A control and three concentrations (1, 10 and 100 mg/kg dry soil (nominal)) were tested for each species. The number of seedlings that emerged were recorded. After 19 days in the test with wheat resp. 20 days in the test with radish and fenucreek the plants were harvested and weighed.

All tested species showed no phytotoxic effects at the tested concentrations of Marlotherm S compared to the control. The LC50 for seedling emergence and the EC50 for growth of Triticum aestivum, raphanus sativus and trifolium ornithopdioides were therefore observed to be greater than 100 mg/kg dry soil.