These are the people you can smell long before you actually see them.
Some of us won't mind their scent and will have no trouble sitting next to them in a meeting. Others will find their fragrance overpowering, but feel fine once they get some 'fresh air'.
But a small proportion of people may leave the meeting feeling unwell, and in some cases, so ill they will need to head home to bed.
For these people, exposure to some of the chemicals in fragrances can cause asthma, skin rashes, hay fever, migraine, nausea and a range of other unpleasant symptoms.
A small number of them become so distressed by perfumes and other chemicals in our environment that they cut themselves off from the rest of us.
In one online survey of more than 1,000 Australians, more than a third reported health problems — such as migraine headaches and asthma attacks — when exposed to fragranced products. Nearly 8 per cent of the respondents said they had lost workdays or a job because of fragranced product exposure in the workplace.
The contents of perfumes are regulated less strictly than our foods and pharmaceuticals, and manufacturers are permitted to put the words "fragrance" or "parfum" on a list of ingredients, rather than naming the chemicals that produce the scent.
Historically, labelling legislation has protected fragrance manufacturers from having to list the chemicals they use to create their fragrances for secrecy reasons, to prevent competitors from discovering their ingredients and copying them.
Perfumes and asthma — not a good mix
Strong smells are one of the more common triggers for asthma, Asthma Australia CEO Michele Goldman said.
"That includes things like perfumes, paints and cleaning materials and also particulates found in aerosol sprays such as deodorants, hair sprays and air fresheners," she said.
Although asthma is usually well-managed with treatments, she says people forget it remains a potentially life-threatening illness.
A post on the Asthma Foundation NSW website about the impact of perfumes generated a lot of discussion, Ms Goldman says.
"That suggests it was a topic that resonated strongly with people."
It's hard to know how many people have their asthma triggered by smells. But 43 per cent of people with asthma registering on the Asthma Foundation NSW website over a six-month period listed 'strong smells' as one of their asthma triggers.
If this is a representative statistic, then about 1 in 25 people on the street can be expected to have asthma that can be triggered by strong smells — though not all of these people will necessarily be triggered by perfume.
Tackling a sensitive issue at work
Tonia developed asthma in her 30s after a severe bout of flu. Normally her asthma is well-controlled, but it flares up when she gets a cold. When this happens, she can't tolerate perfumes at work.
At times, she's had to have difficult conversations with her colleagues.
"I have had to say to colleagues: 'That's a very pretty perfume but I can't stay in the same room with you'," Tonia said.
"I had a cold last week and my asthma has flared up and as a result I can't stand the smell of any perfumes or anything like that. This morning my husband used some hair product and I had to ask him not to use it for the next few days."
For Tonia, when her asthma flares up, exposure to perfumes will make her cough and feel tight in the chest.
Perfumes and migraines — recipe for a sickie?
People with migraine often experience dislike of smells in the hours before and during an attack, a phenomenon called osmophobia, says Brazilian neurologist Professor Raimundo Silva-Néto of the University of Piaui.
Professor Silva-Néto, who researches odour and migraine, has shown 86 per cent of his migraine patients have osmophobia during an attack and nearly a quarter are osmophobic all the time.
What's more, he can produce a headache in more than a third of his migraine patients simply by exposing them to a floral scent for one minute.
Of course, those patients sick enough to be attending a migraine clinic may be at the worse end of the spectrum, but it's likely some people with migraine are triggered by perfume and many will find it unpleasant during an attack.
Hay fever and rhinitis — a minor irritant
Dr Rob Loblay, director of the Allergy Unit at Royal Prince Alfred Hospital in Sydney, says perfumes can be a nasal irritant for people who have hay fever and chronic rhinitis, causing symptoms such as sneezing.
Dr Loblay says there is a subgroup of his patients with hay fever and chronic rhinitis who get their symptoms not from allergic reactions, but from irritants in the environment.
He says they often think their symptoms are from pollen because they worsen in spring, but in fact it is the odour of flowers — including jasmine, gardenia and privet — behind the flare-up.
"These flowers are very strong-smelling and that's often what people are reacting to rather than the pollen.
"And then you ask them and they say, 'Oh yes I have the same sort of trouble with perfume, cigarette smoke, deodorants and cleaning agents'. These are the kind of people that don't like walking down the cleaning product aisles in the supermarket," Dr Loblay said.
"It's quite common — probably about 10 per cent of my hay fever and chronic rhinitis clients [have it] but people often don't complain about it."
When perfumes become the enemy
Dr Loblay specialises in treating people with food intolerances, and says roughly 30 to 40 per cent of his food-intolerant patients are also 'chemically intolerant': having some degree of problem with smells and fumes in their environment. Their symptoms can vary, and include nausea, malaise and headaches.
"For a small proportion of these patients it becomes a chronic, often-distressing, and sometimes-disabling problem and they may end up living the life of a hermit," he said.
The condition, sometimes referred to as Multiple Chemical Sensitivity (or MCS), is not formally recognised by the medical profession.
But leading researcher Professor Jesper Elberling of the Gentofte Hospital in Copenhagen says about one in 300 people have MCS.
"There is a big spectrum of symptoms. You can have one patient saying, 'I react to this perfume and I get a throat problem and headache', and another patient will say they react to the same perfume and they get exhaustion and itchy eyes.
"So when you look at big data from patients there is no pattern connecting symptoms to the exposure," said Professor Elberling.
Negotiating perfumes in the workplace
If fragrance is a trigger for your asthma or migraines, the obvious thing to do is try and avoid it.
While you may be able to do this easily enough at home, it becomes more difficult once you walk out the front door. Things can get really tricky when you're working with someone who's a little heavy-handed with their favourite scent.
You can approach your colleague directly, but if this doesn't work, each state and territory has a body overseeing workplace health and safety, which offers this advice:
- If raising the issue with your colleague doesn't work, speak to your supervisor or employer. If the perfume causes migraines or asthma, this is a risk to health and safety the employer must manage under health and safety legislation.
- Solutions can include minor alterations to the work environment such as separating staff, personal ventilation systems to suit the affected person; flexible working arrangements; using alternative chemicals; restricting the use of fragrances more generally.
- Workplaces can develop "no-scent" policies in consultation with their staff, provide information sessions to their staff, make sure the workplace has adequate air quality, and change to fragrance-free cleaning and deodorising products.