Not the person you were responding to but there have been papers published examining the government using drug metabolites in waste water for targeted enforceme

Not the person you were responding to but there have been papers published examining the government using drug metabolites in waste water for targeted enforcement in Eastern Europe. In the US, that data is still gathered and hasn't been used for enforcement yet as far as I know, but like every other syrupy bit of data the US government sponges up, it will be used for enforcement eventually.