Increase in workplace cannabis use sparks concern

In News5 MinutesBy NZ Trucking magazine21 November 2025

The Drug Detection Agency (TDDA), New Zealand’s largest workplace drug testing provider, has released its Q3, 2025 workplace drug and alcohol findings.

This quarter the most pressing issues for employers include:

  • Cannabis detections jumped nearly 8% nationwide
  • Opioid positivity rates remain stubbornly high and remain at 18.6%
  • Cocaine trends upward in Tasman, Canterbury, The Lakes and North Shore

The Imperans Report provides New Zealand employers with an analysis of drug and alcohol usage trends, combining results from around the nation to empower businesses to engage in proactive workplace risk management.

This quarter, 3.75% of the screenings conducted by TDDA indicated the presence of drugs. THC (cannabis) remains the most prevalent substance detected in workplace drug tests, accounting for 71.1% of total positive testing. Recent data also indicates a generally stable trend in opioid detections, however regions such as Gisborne recorded a sharp quarterly increase of 41.7%.

These results suggest shifting patterns in substance use that requires greater employer awareness and policy reinforcement.

Below are substances detected nationally and compared to Q2 levels from TDDA’s testing results:

  • Cannabis (THC): was present in 71.1% of positive tests, up 7.9% from 63.3% in Q2 2025.
  • Amphetamine-type substances (ATS), including methamphetamine: were present in 23.3% of positive tests, down 7.7% from 31% in Q2 2025.
  • Opioids: were present in 18.6% of positive tests, down 2.6% from 21.2% in Q2 2025.
  • Benzodiazepines (BZO): were present in 2.2% of positive tests, down 2.5% from 4.7% in Q2 2025.
  • Cocaine: was present in 1.5% of positive tests, down 0.2% from 1.7% in Q2 2025.

Overall detections have remained relatively steady but are accompanied by a marked increase in cannabis use. It’s a concern for employers ahead of the holiday season where, traditionally, usage increases during the summer months.

“Cocaine use has been steadily increasing over the year, and we believe that’s in no small part due to cartel activity,” said Glenn Dobson, chief executive, TDDA.

“Cocaine tends to be considered a more white-collar drug, and it has a seasonal pattern where usage tends to increase over the holidays. Corporate businesses have an increased awareness because they’re concerned, and rightly so, about the behaviour of their staff and their company’s reputation.”

As social gatherings rise, the line between recreation and workplace risk can blur. Employers must remember that compliance requires them to keep people safe at events, on-site, and even on the way home.

TDDA tracks regional fluctuations in drug detections to allow employers to better address workplace safety through targeted testing and education services.

These regional shifts underline the importance of regular testing, education, and the basic reminding of staff that the company’s drug and alcohol policy is taken seriously. TDDA recommends educational activity before year-end social events, which often coincide with an unwarranted higher social tolerance for substance use.

“Cannabis has always been an issue for employers, but the data is telling us that use is very prevalent. Opioids saw modest declines in the regions, except for in Gisborne where we’re advising employers to take action now,” said Dobson.

“A 50% surge in detections usually means there is easy access and abundant supply, which creates a risky climate for people conducting business,” he said.

“The early cocaine detections on the North Shore, The Lakes and in Canterbury are also concerning, cocaine is a serious drug and adversely affects performance.”

TDDA recommends that companies review and update drug and alcohol policies as well as to consider return to work testing, to train managers to recognise the signs of use, particularly the subtle signs of prescription medications, and to ensure regular and random drug testing to deter misuse and protect workplace safety.

“Reinforcing policies now can prevent difficult conversations or accidents between employers and employees. Talking about return to work testing reminds people that safety doesn’t take the holidays off and everyone needs to come back to work fit for duty,” said Dobson. “It’s about balancing goodwill with responsibility.”

TDDA drug tests screen for amphetamines; benzodiazepines; cocaine; methamphetamine; opiates; oxycodone; cannabis; tramadol; fentanyl; as well as synthetic drugs like synthetic cannabis.

00:00
00:00
Empty Playlist

Secret Link