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:

The substance is not readily biodegradable achieving 7% in 28 days. Due to high water insolubility (<0.04 mg/L), it is not possible to assess the potential for hydrolysis by testing. The substance is, however a stable organic molecule and is therefore, considered by assessment of structure and experience in use to hydrolyse in the environment.

 

The substance is considered to be very persistent in the environment were exposure to occur based on the known lack of biodegradability.

 

The bioconcentration factor (BCF) has been assessed by four separate techniques to provide for a weight of evidence. These data suggest a likely BCF ranging from 0.6 to 7.43 L/kg wet-wt.

 

The partition coefficient of the substance has been calculated using QSAR estimation based upon the SMILES code of the molecular structure US EPA KOWWIN v1.68 of the EPI Suite v4.1. Based upon structural fragmentation drawn from a database of >40,000 substance, the log Pow is estimated to be 15.18. The extremely high log Pow is likely to be due in part to the hydrophobic nature of the molecule.

 

Furthermore, assessment of the Toxicokinetic activity of the substance, based on a close structural analogue, conducted with a radioisotope demonstrates that 28% was located in the GI tract with the total remaining mass balance (71%) excreted in faeces.

 

Based on these data the substance is considered to be non-bioaccumulating.

 

Eco-toxicity studies:

Due to the substance being highly insoluble in water exposure to three aquatic species (algae, daphnia and fish) have been investigated at nominal concentrations. The toxicological examination on daphnia and algae provided an EC50 >100 mg/L and the results on a close structural analogue on fish produced an LC50 >1000 mg/L.

 

Mammalian toxicity studies:

The substance has been assess for genetic toxicity by three in vitro assays and one in vivo assay, with and without metabolic activation, all four studies demonstrated a lack of mutagenic response.

The Prenatal Developmental Toxicity produced a NOAEL >1000 mg/kg bw/day.

The 90-day toxicity feeding study achieved A NOAEL >1000 mg/kg bw/day with no significant dose-related effects detailed.

 

Considering the toxicological information the substance is not toxic.

 

The substance may pose a persistence (P) hazard but as the results produced no bioaccumulation (B) or toxicity (T) properties the substance cannot be considered as a PBT/vPvBT.

Likely routes of exposure:

The substance is a powder of a particle size that is not breathable and is generally used in closed conditions.

 

The likely route of exposure to workers would be by dermal exposure.