Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
PNEC aqua (freshwater)
PNEC value:
0.07 mg/L
Assessment factor:
1 000
Extrapolation method:
assessment factor
PNEC freshwater (intermittent releases):
0.7 mg/L

Marine water

Hazard assessment conclusion:
PNEC aqua (marine water)
PNEC value:
0.007 mg/L
Assessment factor:
10 000
Extrapolation method:
assessment factor

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
9 mg/L
Assessment factor:
100
Extrapolation method:
assessment factor

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
0.062 mg/kg sediment dw
Extrapolation method:
equilibrium partitioning method

Hazard for air

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
PNEC soil
PNEC value:
0.016 mg/kg soil dw
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Additional information

Conclusion on classification

According to 67/548/EEC Annex I, the substance meets the criteria for classification as harmful to aquatic organisms, which may cause long-term adverse effects in the aquatic environment (R52-53). The Commission Working Group on Environmental Classification and Labelling of dangerous substances has interpretate the data as follows:

[FR and S recommended that the substance should be classified with R52-53. QSAR was not possible as the substance is electrophilic.CEFIC suggested that the substance could be a candidate for the escape clause and not be classified. However, FR stated it was neither readily or inherently degradable. The UK suggested that there might be a pH effect for the ring opening and once open it could be degraded. DK stated the R52-53 was applicable because of ‘stripping’ together with the data from S in an aerobic adapted OECD test.]

 

The main argument for the classification was the lack of data on biodegradation. Since new experimental results show that 1,2-epoxybutane is readily biodegradable (cf. chapter 5.2.1), the data gap on biodegradability of 1,2-epoxybutane is closed. Hence the database for the classification of 1,2-epoxybutane is conclusive. The hazard assessment of 1,2-epoxybutane according to 67/548/EEC (self classification) reveals no need to classify the substance as dangerous for the environment.