diethyl 1-(2,4-dichlorophenyl)-5-methyl-4,5-dihydro-1H-pyrazole-3,5-dicarboxylate

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

other: Along EPPO Guideline No. 170 (1992)

Deviations:

yes

Remarks:

Toxic reference group not included

GLP compliance:

yes

Application method:

oral

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Apis mellifera

Animal group:

Hymenoptera (honeybees)

Study type:

laboratory study

Limit test:

no

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 927 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Findings:

The food uptake per bee was tested in the range from 1.5 to 927μg test item/bee. After 48 hours mortality was very low (2- 14%) in all concentrations without a clear dose response relationship. In addition, no sublethal findings were not in any testing group.

Conclusion:

The test item was of low toxicity to the worker honeybee Apis mellifera after oral exposure as shown by a 48hr LD50 value of > 927 μg test item / bee. Acceptably low (zero) mortality rates was observed in the control groups. In the absence of any sublethal findings the NOEC was > 927 μg test item / bee

Reference 2

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

no guideline followed

Principles of method if other than guideline:

Entomology primary screening

GLP compliance:

no

Application method:

other: by direct treatment or via their feed

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

other: different non target arthropods

Animal group:

other: different non target arthropods

Details on test organisms:

Material and Methods:The safener AE F107892 was tested against the following species:
- Spodoptera littoralis (Egyptian cotton leafworm),
- Aphis fabae (Black bean aphid),
- Trialeurodes vaporariorum (Greenhouse whitefly),
- Nilaparvata lugens (Brown plant hopper),
- Oncopeltus fasciatus (Large milkweed bug),
- Diabrotica undecimpunctata (Southern corn rootworm),
- Tetranychus urticae (Two spotted spider mite),
- Blattella germanica (German cockroach) and
- Musca domestica (Housefly) in the entomology primary screening.

Study type:

other: entomology primary screening

Limit test:

no

Reference substance (positive control):

not specified

Remarks on result:

other: Please see "any other information on results inc. tables"

Findings:

AE F107892 was not effective against any of the tested species.

Conclusion:

The safener mefenpyr-diethyl is not likely to have significant adverse effects on any non-target arthropod species

in the natural environment.

Reference 3

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

other: Along EPPO Guideline No. 170 (1992)

Deviations:

yes

Remarks:

Toxic reference group not included

GLP compliance:

yes

Application method:

contact

Analytical monitoring:

not specified

Vehicle:

yes

Details on preparation and application of test substrate:

The concentrations for the application of the test substance were prepared stepwise: the highest dose level of 74.23 % required in the test protocol was prepared by weighing-out 7.42 g of the test substance in 2.58 g DMSO. The subsequent lower concentrations were then prepared successively by dilution with DMSO.

Test organisms (species):

Apis mellifera

Animal group:

Hymenoptera (honeybees)

Details on test organisms:

TEST ORGANISM
- Common name: honey bees
- Source: colonies kept in close proximity to the laboratory on the ground of Hoechst AG.
- Age at test initiation: approx. 10 - 17 days
- Cultural background (if honeybees):
- Disease free: yes
- Kept according to standard practices: yes

Study type:

laboratory study

Limit test:

no

Total exposure duration:

48 h

Test temperature:

26.5 - 27.0 °C.

Humidity:

30- 35 %

Details on test conditions:

TEST SYSTEM

- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 5
- No. of replicates per control: 5
- No. of replicates per vehicle control: 5




OTHER TEST CONDITIONS
- Photoperiod: The lighting time was 16 hours
- Light intensity: fluorescent strips (model designation TLD 58W/84 from Philips) were used as source of light


EFFECT PARAMETERS MEASURED: Mortality was assessed after 24 and after 48 hours.


VEHICLE CONTROL PERFORMED: yes

Nominal and measured concentrations:

The following dose level series was established: control, 31.81, 42.42, 53.02, 63.63 and 74.23 %. This is equivalent to an active ingredient quantity of 300, 400, 500, 600 and 700 µg active ingredient/bee.

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 700 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Findings:

Significant mortality after 48 h test duration was observed in none of the dose levels tested. After 48 hours

mortality was very low (0- 2%) in all dosing groups up to and including 700 μg/bee. In addition, no sublethal

findings were not in any testing group.

Conclusion:

The test item was of low toxicity to the worker honeybee Apis mellifera after topical exposure as shown by a

48hr LD50 value of > 700 μg test item / bee. Acceptably low (zero) mortality rates was observed in the control

groups. In the absence of any sublethal findings the NOEC was > 700 μg test item / bee

Additional information

The substance is not expected to pose a risk to terrestrial arthropods. There is no indication for high adsorption or high persistence of the substance in soil. The determined log Pow of the substance is 4 and the adsorption potential is low (Koc range 486 – 823). Available tests on the biodegradation of the substance in soil determined half-lives of 7-13 days. Thus a long-term exposure of terrestrial organisms to substance is not likely. The substance is not acutely very toxic to aquatic organisms. All available effect concentrations (EC/LC50) are > 1 mg/L . Furthermore the available acute toxicity test conducted with earthworms determined no toxic effects of the substance. The study was conducted according to OECD guideline 207 (1991) using artificial soil as substrate. Earthworms of the species Eisenia fetida were exposed to a limit concentration of 1000 mg/kg. The artificial soil, prepared from a mixture of dried sphagnum peat, kaolin clay and industrial sand, was mixed with the test substance. No mortalities or symptoms of intoxication were observed. The determined 14-day LC50 was > 1000 mg/kg soil dw was no death occurred at this limit dose. In the absence of any sublethal findings (intoxication symptoms, weight gain and intoxication symptoms) the NOEC (14 d) was 1000 mg/kg soil dw.

Supplementary information on the intrinsic toxicity of the substance after oral and contact exposure is available for the technical substance.

Two studies according to EPPO Guideline No. 170 (1992) investigate the toxicity, both studies were conducted in accordance with the prevailing standard guidelines and GLP. One study investigate the acute oral toxicity and the other study the acute contact toxicity of the substance. Worker bees, Apis mellifera L., from a colony in healthy conditions, were used for both studies. The test item was of low toxicity to the worker honeybee Apis mellifera after oral exposure as shown by a 48hr LD50 value of > 927 μg test item / bee. Acceptably low (zero) mortality rates was observed in the control groups. In the absence of any sublethal findings the NOEC(oral) was > 927 μg test item / bee. In the contact test Mefenpyr-diethyl was also of low toxicity to the worker honeybee Apis mellifera after topical exposure as shown by a 48hr LD50 value of > 700 μg test item / bee. Acceptably low (zero) mortality rates was observed in the control groups. In the absence of any sublethal findings the NOEC(contact) was > 700 μg test item / bee. Therefore, these studies did not reveal any toxic effects up to the maximum dose feasible for technical reason indicating, that the substance is non-toxic to bees. Additionally, one entomology screening comprising 9 terrestrial arthropod species showes that mefenpyr-diethyl is non-toxic.

According to Annex IX, column 2 of Regulation (EC) No 1907/2006, toxicity testing with terrestrial arthropods does not need to be conducted as the Chemical Safety Assessment does not indicate a need for further investigations. According to Annex XI, Section 3 of Regulation (EC) No 1907/2006 toxicity tests on soil macroorganisms are considered not necessary. The exposure concentrations for the terrestrial compartment during the lifecycle of the substance are low. The environmental exposure assessment for the substance indicates no risk for the terrestrial compartment (all RCR< 1; please refer to Chapter 9 and 10 of the Chemical Safety Report for detailed information).