Pyrrolo[3,4-c]pyrrole-1,4-dione, 3,6-bis(4-chlorophenyl)-2,5-dihydro-

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study (Official Journal of the European Communities L133, page 95, 30/05/88) without analytical monitoring

Qualifier:

according to guideline

Guideline:

other: Official Journal of the European Communities L133, page 95, 30/05/88.

Deviations:

yes

Remarks:

, CaCO3 added to correct soil pH was about 8 % of the soil dry weight

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

- Method of mixing into soil: A stock mixture was prepared for each test concentration by premixing the corresponding amount of test substance with 200 g of fine quartz sand. The dry stock mixtures were mixed with the dry premixed artificial soil in a HOBART-blender. Then the required amount of water to obtain the specified moisture content (200 - 500 % of dry weight of substrate) was added. The blend was dispensed into the test vessels and the worms added.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: Farm-Research, Wehr, Germany
- Age at test initiation: Adult mature with clitellum (> 2 months of age)
- Weight at test initiation: 194 - 268 g (based on 10 worms per conc. and blank)
- Keeping: Earthworms arriving from the supplier were kept for 42 days in the original soil before the start of the 24h-conditioning.

ACCLIMATION
- Acclimation period: 24 h
- Acclimation conditions: Same as test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

20 ± 1 °C

pH:

6.4 - 6.5

Moisture:

29 - 37 %

Details on test conditions:

TEST SYSTEM
- Test container: Beakers of 1 liter filled with 750 g soil (wet weight), covered with perforated plastic film
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of controls: 4

OTHER TEST CONDITIONS
- Photoperiod: Continuous illumination / 400 - 800 lux

EFFECT PARAMETERS MEASURED: Mortality

VEHICLE CONTROL PERFORMED: no

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3

Nominal and measured concentrations:

Nominal: 12.3, 37, 111, 333 and 1000 mg/kg dry weight of soil

Reference substance (positive control):

no

Key result

Duration:

14 d

Dose descriptor:

LC0

Effect conc.:

>= 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality at end of exposure period: 0 % in the highest concentration
- Mortality in controls: 0 %

Validity criteria fulfilled:

yes

Conclusions:

In an acute earthworm toxicity study, the substance did not cause toxic effects up to a concentration of 1000 mg/kg soil.

Executive summary:

The substance's toxicity to soil macroorganisms was investigated in an acute earthworm toxicity study that was GLP-compliant.

Earthworms (eisenia foetida) were exposed to the concentrations of

12.3, 37, 111, 333, 1000 mg test substance/kg (dry weight of soil) for 14 days. In addition, a concurrent negative control group was tested.

The group size was 40 earthworms per concentration.

Mortalities and flaccidity of were observed after 7 and 14 days exposure.

The substance did not induce any acute toxic effects.

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Data waiving:

exposure considerations

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of the soil compartment is unlikely

Reference 3

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study (Official Journal of the European Communities L133, page 95, 30/05/88) without analytical monitoring

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The read-across is performed between two forms of the same substance. The identities of the two forms are describe below.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The source form is 3,6-bis(4-chlorophenyl)-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-dione (EC-no. 401-540-3), referred to here as PR254. PR254 is an organic mono-constituent substance with a typical purity of > 99.5% (w/w). It does not contain any impurity relevant for classification or labelling of the substance. The target form is the nanoform of the source substance, referred to here as PR254 nanoform. As the source form, it has a typical purity of > 99.5% (w/w) and it does not contain any impurity relevant for classification or labelling of the substance. The PR254 nanoform is spheroidal with a pure polyhedral shape and is not surface-treated.

3. ANALOGUE APPROACH JUSTIFICATION
The two analogue forms have the same structure. Under ambient atmosphere, the specific surface energy of particles increases with decreasing particle size. Therefore, particle aggregate to reach an energy minimum. The driving forces are hydrogen bonds and van der Waals forces (π-π interaction). Substantial energy is required to disperse the PR254 nanoform aggregates to particles that fall under the nanoform definition.
PR254 was been tested extensively addressing information requirements of Annexes VII to IX without identifying any biological target. PR254 nanoform could potentially have biological targets due to the different particle size distribution, which would require processes capable of dispersing the aggregates, e.g. in aqueous milieu. However, both forms have been tested according to OECD Test Guideline 318, demonstrating that PR254 nanoform cannot be dispersed under the condition of the study, i.e. immediately after sonification re-forms aggregates. Also, PR254 aggregates to a large extent, but can be more easily dispersed than the nanoform. The experiments demonstrated that exposure in aqueous milieu will be primarily to aggregates, regardless of the PR254 form.
Therefore, it is concluded that both forms will behave identically in studies, in which they are applied under atmospheric conditions and/or in aqueous milieus, so that for the PR254 nano-form no specific biological targets need to be considered.
As also the environmental fate is identical, read-across is also justified for sediment and terrestrial toxicity.

4. DATA MATRIX
The data matrix is included as Annex 1 in the assessment report ‘PR254 bulk nano analogue approach 210111’ attached here below under ‘Attached justification’.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: Official Journal of the European Communities L133, page 95, 30/05/88.

Deviations:

yes

Remarks:

, CaCO3 added to correct soil pH was about 8 % of the soil dry weight

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Details on preparation and application of test substrate:

- Method of mixing into soil: A stock mixture was prepared for each test concentration by premixing the corresponding amount of test substance with 200 g of fine quartz sand. The dry stock mixtures were mixed with the dry premixed artificial soil in a HOBART-blender. Then the required amount of water to obtain the specified moisture content (200 - 500 % of dry weight of substrate) was added. The blend was dispensed into the test vessels and the worms added.

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: Farm-Research, Wehr, Germany
- Age at test initiation: Adult mature with clitellum (> 2 months of age)
- Weight at test initiation: 194 - 268 g (based on 10 worms per conc. and blank)
- Keeping: Earthworms arriving from the supplier were kept for 42 days in the original soil before the start of the 24h-conditioning.

ACCLIMATION
- Acclimation period: 24 h
- Acclimation conditions: Same as test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

20 ± 1 °C

pH:

6.4 - 6.5

Moisture:

29 - 37 %

Details on test conditions:

TEST SYSTEM
- Test container: Beakers of 1 liter filled with 750 g soil (wet weight), covered with perforated plastic film
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 4
- No. of controls: 4

OTHER TEST CONDITIONS
- Photoperiod: Continuous illumination / 400 - 800 lux

EFFECT PARAMETERS MEASURED: Mortality

VEHICLE CONTROL PERFORMED: no

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 3

Nominal and measured concentrations:

Nominal: 12.3, 37, 111, 333 and 1000 mg/kg dry weight of soil

Reference substance (positive control):

no

Key result

Duration:

14 d

Dose descriptor:

LC0

Effect conc.:

>= 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality at end of exposure period: 0 % in the highest concentration
- Mortality in controls: 0 %

Validity criteria fulfilled:

yes

Conclusions:

In an acute earthworm toxicity study, the substance did not cause toxic effects up to a concentration of 1000 mg/kg soil.

Executive summary:

The substance's toxicity to soil macroorganisms was investigated in an acute earthworm toxicity study that was GLP-compliant.

Earthworms (eisenia foetida) were exposed to the concentrations of

12.3, 37, 111, 333, 1000 mg test substance/kg (dry weight of soil) for 14 days. In addition, a concurrent negative control group was tested.

The group size was 40 earthworms per concentration.

Mortalities and flaccidity of were observed after 7 and 14 days exposure.

The substance did not induce any acute toxic effects.

Description of key information

In an acute earthworm toxicity study, the substance did not cause toxic effects up to a concentration of 1000 mg/kg soil dw.

Additional information

No key value is indicated, as the substance was not acutely toxic up to 1000 mg/kg soil dw, i.e. the short-term EC50 was > 1000 mg/kg soil dw.