Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

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

Marine water

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

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
1.96 mg/L
Assessment factor:
10
Extrapolation method:
assessment factor

Sediment (freshwater)

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

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
0.008 mg/kg sediment dw
Extrapolation method:
equilibrium partitioning method

Hazard for air

Hazard for terrestrial organisms

Soil

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

Hazard for predators

Additional information

In reality it can be considered that the substance would volatilise completely from the receiving water within less than 1 km from the point of release due to its very high Henry’s Law Constant (242 000Pa m3mol-1). The concept of a long term PNECaquatic is not really meaningful in this context. 

Conclusion on classification

The substance has a water solubility of 19.6 mg/l at 25°C and is highly volatile. On the basis of the fish LC50 of 1.9 mg/l, and no significant biodegradation in a ready test, it is proposed that tetramethylsilane should be classified as follows:

                                        

R51/53 Toxic to aquatic organisms, may cause long term effects in the aquatic environment, according to Directive 67-548/EEC

Chronic Category 2, H411: Hazardous to the aquatic environment, according to Regulation 1272/2008.