Good to hear you passed it – there is currently no test for mephedrone (or other cathinones) in urine.
Still worth being careful – there are swab tests for residues that cops or other security officials could use during a premises or workplace search to gain second level intelligence info (which wouldn’t be enough to justify arrest or court but could be used to justify further surveillance ops on a group of suspected drug users.
BTW it is not just cops or organisations like MI5 who can be authorised these investigations, private security firms and employers can do them although it must still be all done within the law.
I had a look at developments in UK drug testing and unfortunately the US-style culture is finding its way into both private and public sector employers; they are at least doing in accordance with European human rights. I’ve been lucky that I could afford to turn down potential job offers from employers who might routinely drug test (such as HM Coastguard, Border Force and some other similar public services although at the same time I can understand their rationale for drug testing their staff).
