5 Key Takeaways

• 1

  Researchers collected 420 surface swabs over 3 weeks from bathrooms, tables, and a bar in an anonymous pub in southern England.

• 2

  Confirmatory LC-MS detected cocaine in 250 swabs and ketamine in 70; 64 swabs contained both substances.

• 3

  Direct, untargeted ASAP-MS rapidly screened swabs but mainly detected samples with relatively high cocaine levels and missed many residues found by LC-MS.

• 4

  Methanol extraction with targeted ASAP-MS increased sensitivity, but the method still missed 59.51% of cocaine-positive and 88.57% of ketamine-positive samples identified by LC-MS.

• 5

  ASAP-MS produced 15 false-positive results, including apparent ketamine signals linked to procaine, and the researchers said further optimization is needed before routine on-site screening.