Fenamiphos

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial plants, other

Remarks:

Herbicidal screening data on phytotoxic effects after emergence

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 days

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

according to Annex 3 of draft OECD 208 (2000), Annex 3 was not adopted in the final OECD 208 (2006).

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 208 (Terrestrial Plants Test: Seedling Emergence and Seedling Growth Test)

Version / remarks:

according to draft OECD 208 (2000) document

Principles of method if other than guideline:

Method is described to follow Annex 3 of the draft OECD Guideline 208 (2000): Use of Screening/Efficacy Data: Recommended Minimum Data Requirements. The aim of this method is to record potential phytotoxic effects of the test item on at least six plant species from at least four plant families. The more species information available, the more robust the data set and the greater the ability to demonstrate a lack of effect.

GLP compliance:

no

Specific details on test material used for the study:

The test item is Fenamiphos CS 240

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

no

Details on preparation and application of test substrate:

Spray treatments were applied in an automatic spray chamber. The spray chamber was adjusted as follows: pressure 3 bar; height of spray boom 45 cm; nozzle type: 8003E; water application rate to the target area 1000 litres/ha; the material was applied in single applications of 1000, 2000, 5000, 10000 and 15000 g a.i./ha.
For spray treatments the test solutions were briefly shaken and then directly applied through a spraying nozzle. Prior to each application of new test material, the spray nozzle was cleaned at the rinsing station. The adjustments of the spray chamber were recalibrated every six months.

Species:

Zea mays

Plant group:

Monocotyledonae (monocots)

Species:

Beta vulgaris

Plant group:

Dicotyledonae (dicots)

Species:

other: Sinapis alba

Plant group:

Monocotyledonae (monocots)

Species:

other: Setaria viridis

Plant group:

Monocotyledonae (monocots)

Species:

other: Ipomoea herderacea

Plant group:

Dicotyledonae (dicots)

Species:

other: Galium aparine

Plant group:

Dicotyledonae (dicots)

Species:

other: Echinochloa crus-galli

Plant group:

Monocotyledonae (monocots)

Species:

other: Avena fatua

Plant group:

Monocotyledonae (monocots)

Species:

other: Alopecurus myosuroides

Plant group:

Monocotyledonae (monocots)

Species:

other: Amaranthus retroflexus

Plant group:

Dicotyledonae (dicots)

Species:

other: Abutilon theophrasti

Plant group:

Dicotyledonae (dicots)

Test type:

other: Herbicidal screening on phytotoxic effects

Study type:

other: Greenhouse study

Substrate type:

natural soil

Remarks:

A sandy loam with organic matter of 2.5 - 3 %

Limit test:

no

Total exposure duration:

21 d

Remarks:

Plants used in the test were sown, sprayed with the test material and directly placed under the growing conditions. The final evaluation was done 21 days after treatment initiation

Post exposure observation period:

not applicable

Test temperature:

The plants were kept at a day/night cycle of 22 °C/15 °C

pH:

not specified

Moisture:

Growing plants were watered as needed

Details on test conditions:

Typically 10 seeds of each of the 11 species were sown 24 hours prior to application of the test substance. Seeds were planted together in greenhouse pots of 420 cm2 surface (pot T59). The soil allowed good germination.

The relative humidity in the test chamber was set at 50 % and the duration of illumination (8000 lux) was 14 hours to 10 hours in a day/night rhythm. Plants used for the test were sown, sprayed with the test item and directly placed in the test chambers of the greenhouse. The final evaluation was done 21 days after treatment initiation.

Evaluation of phytotoxicity was done by visual observations using a rating scale of 0 to 100 %, where 100 % represented complete destruction of above ground parts and 0 % represented no visual damage (normal growth) as compared to untreated plants.

Nominal and measured concentrations:

1000, 2000, 5000, 10000, 15000 g a.i./ha (nominal test rate)

Reference substance (positive control):

no

Key result

Species:

other: all tested species

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 20 mg/kg soil ww

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

phytotoxicity

Remarks on result:

other: No phytotoxic effects observed at any test rate for any test species. For an application rate of 15000 g/ha, the concentration in soil is 20 mg/kg soil dw. For details see point "any other information on results incl. tables"

Species:

other: all tested species

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 15 000 g/ha

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

phytotoxicity

Remarks on result:

other: No phytotoxic effects observed at any test rate for any test species

Details on results:

All tested plants species showed no phytotoxic effects (0 % = no visual damage, normal growth) up to the highest application rate of 15000 g a.i./ha, corresponding to 20 mg a.i./kg soil dw (please also see "any other information on results incl. tables").

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

not applicable as no effects (0 %) were observed

The highest application rate of 15000 g a.i./ha is converted to receive the concentration in soil for the use in the risk assessment based on the FOCUS model:

Concentration in soil = A x ( 1- fint ) / ( 100 x depth x bd )

where

A = application rate (g/ha)

fint = fraction intercepted by crop canopy

depth = mixing depth (cm)

 bd = dry soil bulk density (g/cm3 )

In compliance with the FOCUS Guidance a bulk density of 1.5 g/cm3 and a mixing depth of 5cm for applications to the soil surface were considered. No interception is considered.

For an application rate of 15000 g/ha, the concentration in soil is 20 mg/kg soil dw.

Validity criteria fulfilled:

not applicable

Remarks:

Method is described to follow Annex 3 of the draft OECD Guideline 208 (2000): Use of Screening/Efficacy Data: Recommended Minimum Data Requirements. No validity criteria are specified.

Conclusions:

In a herbicidal screening test a total of 11 mono- and dicotyledonous plant species were tested under controlled greenhouse conditions in natural soil. 21 d after spray treatment of the potted seeds, phytotoxic effects were evaluated by visual observations using a rating scale of 0 to 100 %, where 100 % represented complete destruction of above ground parts and 0 % represented no visual damage (normal growth) as compared to untreated plants.

All tested plants species showed no phytotoxic effects (0 % = no visual damage, normal growth) up to the highest application rate of 15000 g a.i./ha, corresponding to 20 mg a.i./kg soil dw.

Executive summary:

In a herbicidal screening test following Annex 3 of the draft OECD Guideline 208 (2000), a total of 11 mono- and dicotyledonous plant species were tested under controlled greenhouse conditions in natural soil. No validity criteria are set for the screening test.

Spray treatments were applied in an automatic spray chamber to the potted seeds in single applications of 1000, 2000, 5000, 10000 and 15000 g a.i./ha.

21 d after spray treatment of the potted seeds, phytotoxic effects were evaluated by visual observations using a rating scale of 0 to 100 %, where 100 % represented complete destruction of above ground parts and 0 % represented no visual damage (normal growth) as compared to untreated plants.

All tested plants species showed no phytotoxic effects (0 % = no visual damage, normal growth) up to the highest application rate of 15000 g a.i./ha, corresponding to 20 mg a.i./kg soil dw.

Description of key information

In a herbicidal screening test a total of 11 mono- and dicotyledonous plant species were tested under controlled greenhouse conditions in natural soil. 21 d after spray treatment of the potted seeds, phytotoxic effects were evaluated.

All tested plants species showed no phytotoxic effects (0 % = no visual damage, normal growth) up to the highest application rate of 15000 g a.i./ha, corresponding to 20 mg a.i./kg soil dw.

Key value for chemical safety assessment

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

20 mg/kg soil dw

Additional information

In a herbicidal screening test a total of 11 mono- and dicotyledonous plant species were tested under controlled greenhouse conditions in natural soil. 21 d after spray treatment of the potted seeds, phytotoxic effects were evaluated by visual observations using a rating scale of 0 to 100 %, where 100 % represented complete destruction of above ground parts and 0 % represented no visual damage (normal growth) as compared to untreated plants.

All tested plants species showed no phytotoxic effects (0 % = no visual damage, normal growth) up to the highest application rate of 15000 g a.i./ha, corresponding to 20 mg a.i./kg soil dw.