The lengths people are going to in hiding their drug use from their employers are shocking.
Our front-page story on Tuesday revealed a dramatic jump in number of tests performed across Tauranga and the rest of the Bay of Plenty.
There were 4458 workplace tests conducted last year compared with 1711 the year before. Of those tested last year, almost 400, or on average one a day, tested positive.
But what surprised me more are the crafty ways drug users are using to try and fool the testers and their employers.
Some people add bleach to their urine samples, or use cleansing or flushing pills. Some use a clean sample provided by a friend.
All this suggests drug use among workers and job seekers may be a bigger issue than realised.
The New Zealand Drug Detection Agency Bay of Plenty says more local companies have recognised the benefits of drug testing, not just in terms of safety but also employee morale and productivity.
It is critical that people working in industries such as forestry, construction, the port, trucking and road works are clean and sober so they don't put their own lives at risk or those of other people.
Those drugged on the job in dangerous industries are selfish and deserve whatever penalty they get should they be caught.
But what about other jobs, such as office workers or people who work in retail? I suspect they would be less comfortable about being tested and are perhaps a lower risk.
A company ultimately must reserve the right to do whatever it takes to ensure the health and safety of all staff and to protect property such as fleet vehicles. But if they do it is vital they have clear drug-use policies and communicate well with their staff.
Provisional figures out this week show 41 people died in workplace incidents in 2011. The increase in workplace testing shows more local businesses are getting serious about employee safety, and this is to be applauded.