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Ecotoxicological information

Toxicity to terrestrial plants

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Administrative data

Endpoint:
toxicity to terrestrial plants: short-term
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
The relative phytotoxicity of selected hydrocarbon and oxygenated solvents and oils
Author:
Krenek MR and King DN
Year:
1987
Bibliographic source:
Am. Soc. Test. Mater. Spec. Tech. Publ. (Philadelphia PA): Pesticide formulations and application systems: sixth volume

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Undiluted solvents were applied once at a nominal concentration of 32.7 l/ha in a spray booth to approximately 2 week old postemergent plants (cotton, soybean, corn, wheat) in a greenhouse. There were two replicates for each treatment and observations for phytotoxic effects were made at varied intervals over a 56-hour period.
GLP compliance:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
3,5,5-trimethylcyclohex-2-enone
EC Number:
201-126-0
EC Name:
3,5,5-trimethylcyclohex-2-enone
Cas Number:
78-59-1
Molecular formula:
C9H14O
IUPAC Name:
3,5,5-trimethylcyclohex-2-en-1-one

Sampling and analysis

Analytical monitoring:
no

Test substrate

Details on preparation and application of test substrate:
STOCK AND TEST SOLUTION AND THEIR PREPARATION
- Vehicle, solvent: undiluted, i.e. no vehicle / solvent
- The test item was applied using a spray booth at a controlled nominal rate of 32.7 L/ha

Test organisms

open allclose all
Species:
Triticum aestivum
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
Wheat, strain: Sturdy
- Age: 12-14 days after emergence
Species:
Zea mays
Plant group:
Monocotyledonae (monocots)
Details on test organisms:
Corn, strain: H-TAM50
- Age: 12-14 days after emergence
Species:
Glycine max (G. soja)
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Soybean, strain: Hutton
- Age: 12-14 days after emergence
Species:
other: Gossipium sp.
Plant group:
Dicotyledonae (dicots)
Details on test organisms:
Cotton; strain: Stoneville 825
- Age: 12-14 days after emergence

Study design

Test type:
vegetative vigour test
Study type:
semi-field study
Substrate type:
not specified
Limit test:
no
Total exposure duration:
56 h

Test conditions

Details on test conditions:
TEST SYSTEM
- Test type: one-time spray application "over the top"
- Dosing rate: 3.27 isophorone ml/m2, undiluted
- Exposure vessel type: greenhouse after application
- Number of replicates: 2
- Watering: dist. water with or without 0.33 ml/l "Peters professional  soluble plant food, grade 20-20-20) 

ENDPOINTS ASSESSED
- percentage of leaf surface affected using a scale of 0 to 100, with the untreated controls rated 0   
- The 0-100 ratinges were converted to a simplified classification from A (minimum) to D (maximum effects)
- observation after 4, 8, 24, 32, 48, 56 hours
Nominal and measured concentrations:
Application rate: 32.7 L/ha
Reference substance (positive control):
yes
Remarks:
xylene range aromatic solvent

Results and discussion

Details on results:
Effect of Isophorone on various crops
- corn: class B; max.damage after 4 h (12.5 %)
- wheat: class B; max.damage after 8-56 h (10 %)
- cotton: class B; max.damage after 4 / 24 h (35 %)
- soybean: class D; max. damage after 4 h (50 %)

No plant died, but slight effects were observed on corn, wheat and cotton and maxium effects were observed on soybeans (50 % of the leafes were
damaged). Maximum damage in the overall study was observed after 32 h. Recovery and renewed growth was observed after 56 h. No solvent was 
significantly more phytotoxic than the reference solvent. Low phytotoxicity was observed with non-polar solvents. High phytotoxicity was observed 
with aromatic solvents. The effects of surface tension (limiting contact to leaf surface) and  solution potential for wax layer of leaves are discussed. 
For  clarification further studies would be needed.

Applicant's summary and conclusion