What are the Australian Standard Drug Class Screening Cut-off Levels?

Australian Standard Drug Class Screening Cut-off Levels (Australian Standard AS/NZS 4308:2023 (Urine) and AS/NZS 4760:2019 (Oral Fluid) cut-off levels are usually derived from levels which can be reliably detected in a laboratory.

Australian Standard Drug Class Screening cut-off levels may take other factors into account, such as the cut-off level for cannabis metabolites which makes allowance for passive smoking (it is set at a level that ensures a positive result cannot be obtained from passive smoking).

AS/NZS 4308:2023 (Urine)

Currently in a three year transition period with AS/NSZ 4308:2008 being replaced by AS/NZS 4308:2023. The main change is to decrease the screening cut off for cocaine metabolites from 300 ug/L down to 150 ug/L, and a corresponding drop in confirmatory cut off from 150 ug/L down to 100 ug/L resulting in more detections on site along with confirmatory testing being more likely to match the initial screening result.

The second key change in the updated urine standard is a decrease in the confirmatory cut off levels for Benzodiazepines metabolites from 200 ug/L down to 100 ug/L. This will reduce the likelihood of a non negative on site screen returning a confirmed negative confirmation due to a mixture of metabolites present in the urine with no individual component over 200 ug/L. Screening cut offs for Benzodiazepines remain at 200 ug/L.

Current drug screening cut-off levels per drug class for urine testing – AS/NZS 4308:2008

  • Amphetamine Type Stimulants (300 ug/L)
  • Benzodiazepines (200 ug/L)
  • Cannabis Metabolites (50 ug/L)
  • Cocaine Metabolites (300 ug/L) – changing to 150 ug/L with new standard 2023
  • Opiates (300 ug/L)

AS/NZS 4760:2019 (Oral Fluid)

Current drug screening cut-off levels per drug class for oral fluid testing – AS/NZS 4760:2019

  • Opiates (50 ng/mL)
  • Amphetamine Type Stimulants (50 ng/mL)
  • Benzodiazepines (10 ng/mL) *
  • Cannabis (THC) (15 ng/mL)
  • Cocaine (50 ng/mL)
  • Methamphetamine (50 ng/mL)
  • Oxycodone (40 ng/mL)

 * Testing is optional for BZO based on workplaces specific testing requirements or policies.