The strategies mentioned above regarding grouping can be matched to substance regulation in various ways. Firstly, substances falling within a PMT/vPvM group with little known data could be flagged for follow-up to see if persistence and mobility measurements have been conducted in literature, and if read-across methods (based on patterns with other substances) could be used to fill data gaps. This could help prioritise filling data gaps and would help develop read-across approaches for further substances within the group. Secondly, if any other substance with a similar structure exists in the group and is hazardous (source substance), this could be seen as a reason to investigate for similar toxicological hazards for this substance (target substance). If several members within a group are shown to be PMT/vPvM substances, then a precautionary approach would be to assume all group members with no assessments are similarly hazardous, until there is sufficient scientific data to show otherwise. An overview of an assessment procedure to identify PMT/vPvM substances has also been presented by , suggesting to first assess compounds for persistence followed by mobility and toxicity for both precursors and transformation products .