Registration Dossier

Classification & Labelling & PBT assessment

PBT assessment

Administrative data

PBT assessment: overall result

Reference
Name:
2,5-Diphenyloxazole
Type of composition:
legal entity composition of the substance
State / form:
solid: particulate/powder
Related composition:
Composition 0
Reference substance:
Composition 1
PBT status:
the substance is not PBT / vPvB
Justification:

The PBT screening criteria described in Annex XII of the REACH Regulation have been considered for persistence (P) and bioaccumulation (B).

QSAR modelling for the evaluation of environmental fate predicts half-lives for the substance in a range of environmental compartments. Half-lives are below the screening criteria for freshwater, estuarine and marine waters, marine sediments and soils. The substance just exceeds the criterion for freshwater sediments, although falls below the vP criterion for freshwater sediments. With a tendency for adsorption, the substance is unlikely to be mobile in soils and sediments and adsorb to sludge during sewage treatment processes. On balance, the substance has a low to moderate tendency for persistence in the environment.

A reliable laboratory study reports a measured Log Kow of 4.1. QSAR evidence of reliable Log Kow values (from two separate QSAR models) are also below the B criterion of less than 4.5. The modelled BCF values are substantially less than 2000 (B criterion) and support the Log Kow values (< 4.5) indicating a low potential for bioaccumulation. It is concluded that the greatest

weight is placed on the measured Log Kow from the reliable laboratory study. The supporting modelled QSAR data are also on the reliable and consistent with the laboratory study with all the evidence confirming that the substance is not bioaccumulative (B or vB).

In conclusion, the substance is not a PBT or vPvBT substance.