Registration Dossier

Classification & Labelling & PBT assessment

PBT assessment

Currently viewing:

Administrative data

PBT assessment: overall result

PBT status:
the substance is not PBT / vPvB
Justification:

Persistence assessment:

Biodegradation in water: screening test: The substance is not ready biodegradable.

Hydrolysis: The substance is hydrolytically unstable in water. The half-life is expected to be < 1 hour at 25 ºC and therefore the substance is not persistent.

Conclusion on P / vP properties: The substance is not fulfilling the criteria for Persistence (P).

Bioaccumulation assessment:

The substance undergoes rapid hydrolysis in aqueous to acetone oxime and the corresponding ethylsilanetriol. Using the BCFBAF v3.01model of EPI Suite v4.1, the BCF for acetone oxime was calculated to be 3.162 L/kg wet-wt (log BCF from regression-based method = 0.500). At the same time, silanetriols undergo continuous condensation reactions to produce higher molecular weight siloxanes which are considered biologically unavailable.

It should be also taken into accoun that the estimated log octanol-water partition coefficients (Log Kow) for the degradation products acetone oxime and ethylsilanetriol are 1.20 and -1.87 (EPI-Suite, KOWWIN v1.68). Since being the log Pow <3, they are expected to of low bioaccumulation.

Based on the available information, the test item is determined to have low bioconcentration potential based on the properties of its degradation products.

Conclusion on B / vB properties: The substance is not fulfilling the criteria for Bioaccumulation (B).

Toxicity assessment:

There is no long-term toxicity studies available with fish and crustacea.

Toxicity to aquatic algae: NOEC (72h) = 62.34 mg/L (basis for effect: growth rate).

Moreover, regarding the acute aquatic toxicity:

- Short-term toxicity to fish: LC50 (96h) = 695.76 mg/L (based on mortality).

- Short-term toxicity to aquatic invertebrates: EC50 (48h) = 678.73 mg/L (based on mobility).

- Toxicity to aquatic algae: EC50 (72h) = 315.36 mg/L (based on growth rate).

The substance is not classified as CMR.

The substance is classified as STOT Rep. Exp. 2 (target organ: red blood cells) in accordance with CLP Regulation (EC) No 1272/2008, since significant toxic effects were observed in a 90-day repeated-dose study (oral) conducted in experimental animals within value ranges 10 -100 mg/kg bw/day (read-across from an analogue substance, OECD Guideline 408).

Conclusion on T properties: The substance is a T.

CONCLUSION:

2 -propanone, 2,2',2''-[O,O',O''-(ethylsilylidyne)trioxime (EAC3) is not a PBT or vPvB substance.