Newsletter - PFI Germany Start

46
Newsletter CHEMISTRY
Contact Allergies Caused by Footwear?
Hunt for Allergens
The frequency with which footwear manufacturers
and retailers approach PFI with requests for help
because consumers blame footwear as the cause of
itching feet and blisters is steadily increasing. In some
cases customers even submit allergy ID cards showing
that their treating physician has been able to identify
an allergenic substance. A subsequent laboratory
search for the allergen in the article under suspicion
is like looking for a needle in a haystack. Why is this
so and what makes identifi cation of the substance responsible
for the allergic reaction so very diffi cult?
Some 30 to 40 percent of the population of Germany
is affected by at least one allergy.
Prevalence of allergies in the population
30 % Respiratory tract allergies
10 % Drug allergies
5 to 7 % Food allergies
7 % Contact allergies
2 to 3 % Insect sting allergies
An allergy is an exaggerated response of the immune
system. Its principal task is to recognise environmental
toxins, irritants, and foreign organisms – such as
bacteria – and to effectively protect us against them.
It is constantly monitoring the entire organism and is
on the lookout for “intruders”. Anything the immune
system regards as “foreign” will initially be classed as
an “intruder”. This will not always be a harmful substance
in the sense of a toxin. It may be a “perfectly
normal” food ingredient or fragrance.
The immune system is particularly active at those parts
of the organisms most likely to come into contact
with the environment, such as the skin, mucous membranes,
or the gastrointestinal tract. It ensures that
the “intruders” can do no damage. This non-specifi c
protective mechanism normally proceeds completely
unnoticed and without any bodily reaction.
What Causes an Allergy and When Is
an “Intruder” an “Allergen”?
If the burden placed on the human body by intruders
is extreme and the situation possibly compounded by
physical or psychological stress, the immune system is
compelled to mobilise additional forces to counter the
attack. This “reinforcement” can offer a signifi cantly
greater defence potential. The effects can manifest
themselves as reddening of the skin, infl ammation, or
tissue damage. If the immune system overreacts in this
way, the intruder triggering the reaction is designated
as an “allergen”.
Once the immune system has combatted a given “allergen”
it “memorises” precisely that allergen in order
to react rapidly on renewed contact (immunity). This
process is also described as sensitisation. Renewed contact
with the allergen can then trigger a very powerful
defence reaction. Allergic immunity is thus primarily
a defence mechanism against intruders lurking in the
environment.
In the case of a “massive attack” by allergens the defence
reactions can even give rise to damage. Starting
with reddening via hive formation and itching all the
way to respiratory distress or circulatory complaints,
in extreme cases the result may be a
so-called anaphylactic shock, possibly
even with fatal consequences.