By Jane Elliott
Health reporter, BBC News
When Donna wants some fresh air, she stays clear of people wearing scents
Donna Robertson's Glasgow home is perfume-free.
One whiff of perfume, aftershave, air freshener, fabric conditioner or even furniture polish and she could be ill for days.
Donna, 61, has been diagnosed with an allergy to perfumes and chemical cleaners.
But she believes she actually has multiple chemical sensitivity (MCS), a controversial condition which some believe is triggered by exposure to chemicals, but others doubt exists at all.
She asks guests to ensure they do not wear perfumes when they visit her and even the children she babysits for must have their clothes washed in non-perfumed brands.
Protecting her health
"People must think I am daft, cuckoo, but I have got to get them to do it, because if they don't I could be ill the whole day," she said.
"My house does not have a single perfume smell anywhere.
"I don't know how my partner puts up with me. I must make his life a misery.
"He paints, and as soon as he gets in the house I make him take his overalls off," she said.
But although Donna can make her own home a fortress against chemicals she admits it is a different matter when she steps over the threshold.
"I walk a lot. I try to avoid public transport. Every man has hair gel or aftershave on and that is really offensive to me. If I go on the bus I have to put something over my face.
"I am not going to stay in and give up but I feel like a prisoner.
"I do go out, but in short bursts as shops and public transport always smell of perfumes.
"I love people and chit chat, but now it is on the phone or over the internet.
"Going out with friends can cause problems because they all have perfumes. My close friends are adaptable, but you can't go to the pub because that is a killer. It makes you really anti-social."
Donna first started noticing her problem as a teenager working in a printing factory.
Here she was exposed to lots of chemicals, glues and varnishes. She said she was not supplied with a mask and started suffering repeated nausea.
Then she started having reactions to chemical sprays in her home, but they did not get really bad until the 1970s when more and more perfumes came on the market.
"They were the really strong long lasting ones, she said.
"I was starting to look like a ghoul with dark circles above and below my eyes, feeling tired and sick all the time," she said.
But Donna said that, despite the severity of her symptoms and a positive test showing she is allergic to perfumes, few medics take her condition seriously.
Many do not believe MCS even exists, and she has diagnosed herself because she could not find a GP sympathetic to her belief in MCS.
"You can't get help on the NHS in Scotland," she said. "They just don't want to know. They don't even recognise the name.
"I thought I was the only person in the world who had this. I was looking into things being wrong with my brain, mental disorders, the whole gamut, because I was determined to find out what was wrong.
"Even my mother used to say it was all in my imagination."
But Donna said her symptoms are all too real, from nausea and sticky eyes to tiredness, yawning, mood swings, dizziness, loss of concentration, poor memory, muscle pains, knees swelling, headaches, depression, sweats, rapid heartbeat and bloating.
Dr Andy Jones, a lecturer in environmental sciences at the University of East Anglia, said MCS was rare but a very debilitating for those with it.
"In extreme cases some people can't really leave the house. The diversity of the symptoms is such that it is a very unpleasant thing to suffer from."
But Dr Jones, an expert in allergies, said the condition is very difficult to diagnose.
"If you go to the doctor with eczema, it is obvious you have eczema or asthma whereas MCS is probably not one condition.
"It might be a range of conditions that manifest themselves with quite a wide range of symptoms. It is probably one of those things that is under-recognised."
And he said there was a division among the medical community about whether the condition even existed.
"If you talk to the medics there is the camp that sees it as a real condition and there is also the camp that does not believe MCS exists. So there is some debate into what it is.
"Some people argue that MCS are derived from psychological stems - not that people are making up their symptoms.
"There is evidence that people who have other stressful life issues are much more likely to show symptoms of MCS, which raises doubts about whether it is sensitivity to chemicals or as a result of stress induced illness."
A spokesman for Allergy UK said people with MCS were often sidelined, like Donna, because of a lack of comprehension particularly among medics.
"MCS is a little-understood condition particularly by the medical profession, and sufferers often lose support from their family and friends because of the lack of knowledge by the professionals," he said.
"It is so often dubbed as being 'all in the mind' with sufferers losing their livelihood, friends and homes.
"There are obviously extremes of the condition but we are hearing from more and more sufferers all the time."