Reaction mass of 2-(3-ethylphenyl)oxirane and 2,2’-(1,3-phenylene)dioxirane and 2,2'-(1,4-phenylene)dioxirane

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

0.001 mg/L

Assessment factor:

1 000

Extrapolation method:

assessment factor

PNEC freshwater (intermittent releases):

0.012 mg/L

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

0 mg/L

Assessment factor:

10 000

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

1.6 mg/L

Assessment factor:

100

Extrapolation method:

assessment factor

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

0.012 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

0.001 mg/kg sediment dw

Extrapolation method:

equilibrium partitioning method

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

0.002 mg/kg soil dw

Extrapolation method:

equilibrium partitioning method

Additional information

PNECaqua freshwater

 

PNEC=0.0012 mg/L

Assessment factor: 1000

 

Short-term toxicity studies in fish, daphnia magna and algae are available. The PNEC can be derived on the basis of these three short-term studies. An assessment factor of 1000 is applied in line with chapter R.10 of the guidance documents (ECHA 2008). The lowest EC50 of 1.2 mg/L was observed for daphnia magna. The PNEC_aquais therefore 1.2 mg/L / 1000 = 0.0012 mg/L.

 

PNECaqua marine

 

PNEC=0.00012 mg/L

Assessment factor: 10000

 

Short-term toxicity studies in fish, daphnia magna and algae are available. The PNEC can be derived on the basis of these three short-term studies. An assessment factor of 10000 is applied in line with chapter R.10 of the guidance documents (ECHA 2008). The lowest EC50 of 1.2 mg/L was observed for daphnia magna. The PNEC_aqua,marineis therefore 1.2 mg/L / 10000 = 0.00012 mg/L

 

PNECaqua intermittent

 

PNEC=0.012 mg/L

Assessment factor: 100

 

Short-term toxicity studies in fish, daphnia magna and algae are available. The PNEC can be arrived on the basis of these three short-term studies. An assessment factor of 100 is applied in line with chapter R.10 of the guidance documents (ECHA 2008). The lowest EC50 of 1.2 mg/L was observed for daphnia magna. The PNEC_{aqua,intermittent}is therefore 1.2 mg/L / 100 = 0.012 mg/L

 

PNECsediment freshwater

 

PNEC= 0.012 mg/kg_dw

Extrapolation method: partition coefficient

 

The equilibrium partitioning method (EPM) was applied using the lowest reported Koc of 64.4. This leads to a worst case estimation of the PNECsediment of 2.62E-03 mg/kg_wwt, corresponding to 0.012 mg/kg_dw.

 

PNECsediment marine

 

PNEC= 0.0012 mg/kg_dw

Extrapolation method: partition coefficient

 

The equilibrium partitioning method (EPM) was applied using the lowest reported Koc of 64.4. This leads to a worst case estimation of the PNECsediment of 2.62E-04 mg/kg_wwt, corresponding to 0.0012 mg/kg_dw.

 

PNECsoil

 

PNEC= 1.71E-03mg/kg_dw

Extrapolation method: partition coefficient

 

The equilibrium partitioning method (EPM) was applied using the lowest reported Koc of 64.4, the highest reported water solubility of 2.76 g/L, the vapour pressure of 4.3 Pa at 25°C and a molecular weight of 148 g/mol. This leads to a worst case estimation of the PNECsoil of 1.51E-03 mg/kg_wwt, corresponding to 1.71E-03 mg/kg_dw.

 

PNECstp

 

PNEC: 1.6 mg/L

Assessment factor: 100

 

One study on the toxicity to micro-organisms is available.The PNEC can be arrived on the basis of the EC50 derived in this study. An assessment factor of 100 is applied in line with chapter R.10 of the guidance documents (ECHA 2008). An EC50 of 160 mg/L was observed. The PNEC_aqua,marineis therefore 160 mg/L / 100 = 1.6 mg/L

 

 

References:

 

ECHA, (2008). Guidance on information requirements and chemical safety assessment. Chapter R.10: Characterisation of dose [concentration]-response for environment.: European Chemical Agency, May, 2008.

Conclusion on classification

The substance is classified as regards ecotoxicological endpoints. It was found to be toxic to fish, aquatic invertebrates and algae but non-toxic also activated sludge in studies conducted to OECD guidelines.

The test material attained 16% degradation based on CO2 evolution after 28 days and 45% based on DOC removal. It is therefore not considered 'readily biodegradable' under the strict terms and conditions of OECD Guideline No 301B though under the physiologically relevant conditions of pH 1.2, 37.0 ± 0.5°C, the test material was determined to undergo essentially spontaneous hydrolysis and the Log Pow is <3.

The substance is therefore classified as regards it's possible long-term effects on the aquatic environment.