A report into an incident that put a dozen Qantas staff in hospital after they smelt an unknown substance in a downtown Auckland high-rise has failed to find a
cause - strengthening initial suspicions it was a case of mass hysteria.
Psychogenic, also known as psychosomatic, is when an illness is caused by "your psychology rather than being a medical cause", said University of Auckland forensic physician and social contagion expert Felicity Goodyear-Smith.
WorkSafe's report into its investigation of the incident in Victoria St's Augusta Building, released to the Herald under the Official Information Act, showed numerous tests took place after the alarm was raised twice in the same location one day in May.
In the second incident three Qantas workers were taken to hospital. A hundred other workers also needed health checks following the incidents.
But no cause was found.
"We have been unable to identify whether there was ever any type of gas. And, if there was a gas, the type and source of the gas, fume or substance that caused the reaction to multiple Qantas staff members," wrote WorkSafe inspector Lea Wakefield.
They eliminated natural gas or Freon - an aerosol propellant, refrigerant or organic solvent - leaks as the cause.
Fire and Emergency's photoionisation detector and the New Zealand Defence Force's chemical warfare agent and toxic industrial chemical gas and vapour detector didn't identify any volatile organic compounds in the atmosphere shortly after the incident.
Hospital blood tests of some of those unwell also showed nothing and a contractor found the air conditioning was working properly.
Occupational hygienist Philippa Gibson told WorkSafe carbon monoxide potentially rising through the fresh air system from a truck seen parked outside the neighbouring Countdown loading dock, and burning of bitumen roof tile products on a nearby building, were unlikely to be concentrated enough to have contributed to the first incident, which occurred around 8am.
There had been no further reports of incidents at the building and there were also no ongoing health issues with affected staff, Wakefield wrote.
"We have no further testing available to establish what caused this incident."
According to Wakefield's report, emergency services were called after 12 Qantas workers on level 8 smelt strong smells and suffered from nausea, vomiting, a metallic taste, sore eyes, feeling heavy and having burning throats. They were discharged the same day.
The building was evacuated but by 6.30pm occupants had returned and another three Qantas workers reported feeling unwell. They were taken to Auckland City Hospital.
"It was believed by attending medical staff that these three had unrelated conditions ... possibly psychosomatic."
The building is owned Heng Yue Victoria Limited but is managed by Bayleys Property Services property manager Hamish Mackereth. Mackereth couldn't be contacted.
Qantas Airways corporate communication senior manager Stephen Moynihan said they had nothing to add, but said that while three staff were noted in the report as having possible psychosomatic conditions, 12 other staff were "hospitalised and treated for a range of symptoms".
Goodyear-Smith said psychogenic symptoms were real, it was just the cause was psychological rather than physical.
The Augusta incident sounded like a case of social contagion, although the cause of the workers' illness would never be known for certain.
"The problem with social contagion is that it's a diagnosis of exclusion. But it's a typical situation where you have people who, for instance, smell something and ... they interpret it as something harmful, and [then] a few other people talk about it.
"If you're anxious that this is something that has harmed you, then you will get symptoms and the symptoms are real. You may feel short of breath, have stinging eyes, feel a bit nauseous. If you're in contact with other people who feel the same, it's contagious."
A hallmark of psychogenic illness and social contagion was that when people left the site of the assumed toxin they recovered quickly, but then deteriorated if they returned — which had happened when, according to the report, some Qantas staff felt sick again when their clothes were returned to them at hospital.
The emergency response to such incidents had to be real "because we don't know" until later, although she cautioned employers and other responders to consider a psychogenic incident as a possibility at the outset.
"It may be a real harm here but it may also be psychogenic. If you see that nobody's harmed ... if you can quell it at that point there's an opportunity possibly to not go to the huge expense of these investigations."
A WorkSafe spokeswoman couldn't say how much the investigation cost as the regulator doesn't cost investigations individually.
Social contagion wasn't going away — cases in medical literature date to the 1700s, and to suffer it was to be human, Goodyear-Smith said.
"We've evolved to be social animals, to work together as teams to actually respond to others' emotional states ... it's part of who we are and it's a valuable response, but in some contexts now it becomes inappropriate, if the danger is not real."
What is psychogenic/psychosomatic illness?
It's when symptoms of being unwell, such as nausea, shortness of breath or sore eyes, have a psychological cause, rather than a physical one.
What is social contagion?
It's when people are affected by the emotions and responses of others around them. This can include anxiety and panic, but also joy.
Has this happened before?
Yes. There are many cases in medical literature as far back as the 1700s, and other cases are thought to have occurred even earlier.
Among the most famous was the Salem witch trials, when a group of Massachusetts girls claimed in 1692 to be possessed by the devil and accused several women of witchcraft - 19 would hang.