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Hayfever/Rhinitis and Ozone
In Positive Health's ongoing
Allergy Series, Dr Jean Monro, international expert in Allergy
and Environmental Medicine, elaborates upon the contributing
factors behind Hayfever, which now afflicts 20% of the UK
population.
Hayfever was first described by a physician at the beginning of
the industrial revolution in 1819, who described it in himself.
He called it seasonal catarrh (catarrhus aestivus). It took him
nearly ten years to identify a dozen other sufferers. That is
how uncommon it was before the industrial revolution. Now it is
twice as common in towns as it is in the country, largely as a
result of road traffic pollution and the effect of sunlight on
it "petrochemical smog".
Its incidence has steadily increased since then and it now
affects almost 20% of the population of the UK. The peak age for
contracting hayfever is twenty years, although many children
suffer, and it may develop at any age. Hayfever sufferers are
statistically more likely to have been born in the two to three
months before the pollen season which may indicate that exposure
in early infancy may sensitise to allergens which cause hayfever
in later life.
Chronic rhinitis is estimated to affect 1 person in 6;
approximately three quarters of the children aged under 16 years
with rhinitis, and one third of adults have allergic rhinitis
with seasonal symptoms or other factors like animal exposure
which can provoke the rhinitis. Itching of the nose suggests
allergy. Non-infectious, non-allergic rhinitis can be diagnosed
by exclusion, and usually there are food allergic components in
that condition. Some people have rhinitis provoked by oral
contraceptives, aspirin, pain-killing drugs which are
non-steroidal anti-inflammatory drugs or by the dye tartrazine,
which is used as a food colouring. Sometimes people with chronic
rhinitis which is exacerbated in the summer months can have an
infective cause underlying the problem. Hayfever itself,
however, occurs predominantly in the grass pollen season.
Pollution: This is largely as a result of pollution and the
photochemical reaction caused by sunlight, which releases ozone
from sulphur and nitrogen dioxides. Ozone is a potent sensitiser
of the nasal and lung linings and makes them more likely to
react allergically to pollen and dust, producing the symptoms of
hayfever (itchy, runny, blocked nose and sneezing, itchy, red,
streaming eyes) or of asthma (cough, wheeze and shortness of
breath).
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