Exposure to chemicals can be a life sentence for those with MCS. Iva Pocock reports.
Ever balked at a colleague's deodorant, excused yourself on the whiff of a certain perfume or been repulsed by a car freshener bobbing from the rear-view mirror?
If so, you've a sensitive sense of smell, and may well be happier with non-perfumed, natural cosmetics, shampoos and household cleaners than some of the strongly scented products available.
If you suffer from Multiple Chemical Sensitivity (MCS), exposure to such chemical smells will affect you much more dramatically - standing beside someone with perfume may literally bring you to your knees; cooking over a gas cooker may give you a migraine; wearing freshly dry-cleaned clothes may send you to bed for a week.
One such person is Aoife Fitzgibbon whose husband is Galway-based GP Dr Joe Fitzgibbon.
"For four and a half years my wife suffered from debilitating fatigue and hemiplegic migraine. We discovered that if we removed her from chemical sources, she stopped getting them," explains Dr Fitzgibbon.
They got rid of their gas cooker on realising Aoife was highly sensitive to the fumes.
"Four and a half years of sheer agony came to an end in a week," he says.
The episode changed his "entire practice" and led him to specialise in chronic fatigue, allergies and chemical sensitivity.
MCS is characterised by a huge variety of symptoms and a lack of a definitive. "We don't have a practical reliable test so you end up with the patient's testimony," says Dr Fitzgibbon.
"There is no blood test; there is no skin test."
While some medics don't accept the diagnosis of MCS, Dr Fitzgibbon does, saying "I tend to believe my patients."
A widely accepted definition of MCS is that it is a chronic condition characterised by multiple symptoms, in multiple organs, affecting multiple senses, and triggered by multiple chemicals.
It is related to toxicant-induced loss of tolerance (TILT), says Dr Fitzgibbon, by which someone is perfectly well until they are exposed to a toxic substance.
"They recover from this toxic event but they then become sensitive to other things and can develop food intolerance.
"There have been very cogent arguments in research by Claudia Miller in the USA that this is a distinct clinical entity," he says.
To date, the mechanism by which this intolerance is activated is not understood, and thus it is controversial, says Dr Fitzgibbon.
However, MCS is a real problem for a very small proportion of the population "and their lives can be very disturbed by it", he says.
Many chemically sensitive patients who have not been accurately diagnosed struggle to find a doctor who won't dismiss their symptoms as psychosomatic.
One such woman is 35-year-old Wendy Hayes.
She spent weeks in numerous hospitals and was seen by endless doctors over a two-year period from October 1999 - the date when all her muscles "gave up".
"I was working in Dublin using a lot of paint and silicone and one day I started walking sideways and talking funny," she says.
She initially spent five weeks in Tallaght hospital and couldn't work properly until March 2000.
"I had a lot of tests for things such as low thyroid and rheumatoid arthritis but never did they think it was chemical sensitivity. One consultant even asked my parents was I having boyfriend trouble."
In 2001 she was at her wits end, having been admitted to hospital the day after she went to a wedding. In hindsight, it was being exposed to the guests' perfumes which debilitated her.
"They sent for my parents immediately. I was really very ill," she says.
She made it through and "was slowly realising that certain things were making me sick".
As a last resort, she made an appointment with Dr Fitzgibbon, whom she had read about in a magazine article.
Dr Fitzgibbon's diagnosis that she is chemically sensitive and hyper-allergic to many things was the beginning of her road to recovery, and of the realisation that to stay well she must avoid numerous everyday items.
"I had a gas cooker and oil-fired heating but a month after getting rid of them my life was transformed," she says.
"The better I got the more I could identify things I was sensitive to such as perfumes, washing powder, fabric conditioner, shoe polish, window cleaner and petrol fumes."
Learning to avoid such products (which means avoiding public places, especially pubs as, post-smoking ban, many use plug-in air fresheners) has been a struggle but the other great difficulty is trying to get friends and family to realise that their perfume or body lotion could leave Wendy confined to bed for a week.
"It's very, very hard for people to understand," she says.
"The only people who really understand are those who have seen me unable to walk."
Case studies: chemical reactions
Derval Dunford, (38), a beautician and make-up artist in Westport, Co Mayo:
Derval became chemically sensitive in 2000 after being exposed to body spray. "It was from that evening that I was so tired."
Her main symptoms are headache, nausea, chronic fatigue or dryness in the throat and she reacts most strongly to strong perfume, false tan and oil paint.
"The reason I know I get my hangovers and symptoms from the chemicals is from constant monitoring over the past year.
"Last week someone came into my house with perfume on for five minutes. That evening I had a muzzy, dizzy feeling and was very tired.
"The next day I felt like I had a hangover with nausea, really bad fatigue. I felt miserable and quite down."
She points out that in Nova Scotia, Canada, perfumes are banned in public buildings to protect those who are chemically sensitive.
Her social life is very badly affected. "I can't eat out unless I eat at 6 p.m. in a restaurant in the hope that no one else will be out. If someone comes in with perfume on, I have to leave."
Unfortunately, she now thinks she is becoming sensitive to make-up, which obviously has implications for her work.
"If I inhale a product, I'm affected so, as far as I can see, the best way is to avoid it," she says.
Sandy Perceval, retired sheep farmer, Co Sligo:
Sandy's life has been totally changed by his chemical sensitivity. He can't go to any public places and when driving he has a face mask close to hand because his body's reaction to chemicals is so extreme - the smell of a perfume through his car window could prompt a seizure within minutes.
His chemical sensitivity was brought on by re-exposure to organo-phosphate sheep dip, which he had managed to avoid for nine years by switching to organic farming. In 1991 being 80 yards from a flock of freshly dipped sheep left him paralysed down one leg and confined to bed.
He then decided to retire from farming and to help his wife, Debbie, run a guest house in his old family home. Visitors were given strict instructions not to bring any perfumed substances to the house.
Sandy says he has come across thousands of people who are chemically sensitive. "There are 1000s of products on the market which weren't there 30 years ago. A lot of people have no immunity to them."
A lot of chemically sensitive people can start off with a very sensitive sense of smell, he says. "My personal opinion is that the best way to beat it is avoidance."
Dr Joe Fitzgibbon specialises in allergies and chemical sensitivity