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

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.01 mg/L

Assessment factor:

10

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.024 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0.001 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

PNEC marine water (intermittent releases):

0.002 mg/L

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

10 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

0.522 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.052 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

1 mg/kg soil dw

Assessment factor:

1 000

Extrapolation method:

assessment factor

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Conclusion on classification

Environmental fate and pathways

Biodegradation:

The substance is not readily biodegradable according to OECD criteria. In soils and sediment systems a rapid formation of metabolites was observed. The determined half-life of the parent substance in sediment systems was < 2 d at 20°C. In soils a half-life of 12 d at 20°C was determined.

 

Bioaccumulation:

Log Kow: 3.83 (OECD 107)

 

Acute aquatic toxicity:

- Fish: LC50 (96 h): 2.4 mg/L (nominal)

- Aquatic invertebrates: EC50 (48 h): 5.9 mg/L (nominal)

- Aquatic algae: ECr50 (96 h): 12.57 mg/L (nominal)

 

Chronic aquatic toxicity:

- Fish: NOEC (28 d): 0.1 mg/L (nominal)

- Aquatic invertebrates: NOEC (21 d): 0.32 mg/L (nominal)

- Algae: NOErC (72h): 4.35 mg/L (nominal)

 

Classification justification according to CLP

Based on the data above, the substance has a low potential to bioaccumulate. The effect concentrations for acute aquatic toxicity L(E)C50 are > 1 mg/L for fish, daphnia and algae. The lowest chronic effect concentration was determined for fish NOEC (28 d): 0.1 mg/L. Thus the CLP trigger value for Category Chronic 2 is > 0.01 to ≤ 0.1 mg/L (EC No 1272/2008). In the available chronic fish study no effect occurred at the threshold concentration of 0.1 mg/L. First effects were seen at the next higher test concentration (0.32 mg/L).Therefore the Maximal Acceptable Toxicant Concentration (MATC) in this study was determined to be 0.18 mg/L (geometric mean of 0.1 – 0.32 mg/L). However the reported NOEC of this study is 0.1 mg/L is considered as trigger value.

The substance is not readily biodegradable. The half-lives for primary degradation in soil and sediment are < 12 days. The degradation productsdo notfulfil the criteria for classification as hazardous to the aquaticenvironment.All available acute and chronic effect concentrations for the metabolites are> 1 mg/L (fish, daphnia and algae).

Therefore, the substance needs to be classified and labelled as environmental hazard Chronic Cat. 2 according to the Regulation (EC) No. 1272/2008 (CLP) and the Regulation (EU) No. 286/2011.