摘要：European regulatory frameworks for chemicals (i.e. registered under REACH, plant protection products (PPPs), biocides, human and veterinary medicinal products) require that substances undergo an assessment to identify whether they are persistent (P), bioaccumulative (B) and toxic (T), or very persistent (vP) and very bioaccumulative (vB), i.e. to identify them as PBT substances or vPvB substances according to their properties. We screened current practices, evaluated possibilities and made a proposal for a harmonised assessment. Our proposal assumes that it should be possible to identify PBT and vPvB substances on the basis of the data available according to the requirements of the respective legal frameworks. For substances registered as PPPs and mostly also biocides and medicinal products, a ‘definitive assessment’ is often possible. Within REACH, the registrant has to provide all information necessary for PBT assessment regardless of the yearly tonnage of chemicals. But in cases of limited data availability, we suggest using a weight of evidence approach to account for such differences in data availability and type of data across different frameworks and to make use of valuable additional information. We propose to base the evaluation of persistence on degradation half-lives and to normalise a number of parameters (e.g. type of kinetics used, temperature). But further work is needed, e.g. for deriving DegT50 for water and sediment compartments. For the B-criterion, information other than BCF in fish could be considered and more information related to bioaccumulation processes should be gathered (e.g. in species other than fish, different uptake routes). Testing for T identification is focused on standard aquatic species but could also be complemented by e.g. information from other species. Information such as those read-across from structurally related substances and QSAR are often of importance for screening assessments. The aim of PBT and vPvB identification is to reliably target the problematic substances, with as few false negatives or positives as possible, regardless of the regulatory framework. Each aspect was thus considered in the context of the others for a final balanced decision. As the need for conservatism is interpreted differently under the various frameworks, harmonizing this identification is a challenging task.
