On January 6th 2017, the Forensic Science Regulator published the 2016 annual report.
Under Toxicology standards, 'General Forensic Toxicology' and 'Drug Driving' are mentioned.
There is also a statement in relation to the Psychoactive Substances Act 2016.
To view/download this please go to https://www.gov.uk/government/publications/forensic-science-regulator-annual-report-2016