Invercargill's two MPs have gone head to head over synthetic urine, of all things.

National MP Penny Simmonds has taken Labour List MP Liz Craig to task over the her her opposition to a private members' bill which prohibits the sale of synthetic urine to pass workplace drug tests.

Simmonds says Dr Craig has let down Invercargill employers. Craig says it is more nuanced than that. 

Craig spoke in the house, on Wednesday night, opposing National MP Matt Doocey's private members’ Synthetic Urine ( Prohibition on Importation, Supply and Acquisition to Pass a Workplace Drug Test ) Bill.

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"I am disappointed and concerned at Ms Craig’s opposition to this Bill, which would effectively prevent workers from cheating the system and getting around workplace drug testing," Simmonds says.

"Employers are concerned about the use of fake urine to cheat workplace drug tests and New Zealand's largest drug-testing agency has also seen a rise in its use. I am at a loss as to why Ms Craig would not support this important bill.

"Drug testing in the workplace is used to keep people safe and prevent accidents and deaths, if this testing is manipulated, it puts both employees and employers at risk."

Invercargill's National MP Penny Simmonds

Some New Zealand retailers are openly advertising and selling synthetic urine to cheat a drug test and it can also be freely sourced online.

Craig agrees safety in the workplace is important and says its vital that workers are not impaired by alcohol or drugs when they're at work. 

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"However, it's unclear whether banning synthetic urine will make workplaces any safer, or just lead to people switching to other ways of trying to beat a drug test, like asking friends or family for a sample, or trying one of the unproven 'detox' products currently on the market," Craig says.

"There are also issues with urine testing itself, with for example, cannabis being detected in the urine for days or weeks after use, meaning it's hard to differentiate between previous use and impairment on the job. In contrast, saliva tests are harder to cheat on, and are better at identifying more recent use."

Invercargill-based Labour List MP Dr Liz Craig

"Improving safety at work needs to focus on addressing impairment, not only from drugs but also from alcohol, fatigue and work related stress, all of which can impact workers' performance. This means having good relationships between workers and management, a culture of reporting health and safety risks, and encouraging people to speak up if one of their co-workers seems impaired. Within such a framework, impairment testing, along with drug testing if required, may be an appropriate approach. 

"The banning of synthetic urine is unlikely to achieve any of this and may well take the focus away from the action that is required."

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