Irritant Contact Dermatitis
The most common type of hand eczema is irritant
contact dermatitis, an effect of repetitive
damage to the skin. The most common cause is
wet work, i.e., skin contact with water and detergents.
Many female-dominated occupations involve
extensive wet work. This applies to most
occupations in the care and service sectors, such
as hairdressing, catering and cleaning. Since
women are affected by irritant contact dermatitis
to a greater extent than men, the question has
arisen as to whether women have more sensitive
skin. Skin irritation can be studied using several
objective methods, most commonly transepidermal
water loss (TEWL) by evaporimetry and
blood flow by laser Doppler technology. Major
differences have been observed between individuals,
though no difference between the sexes has
as yet been confirmed (12). Differences in occurrence
of irritant contact dermatitis between
males and females are therefore most likely due
to differences in exposure. Exposure at the workplace
is probably the most important factor, due
to the amount of time spent at work, though
many women spend further time performing wet
work at home, especially young women with
small children. A prospective study of female
nursing staff in northern Sweden showed that the
presence of children under the age of 4 in the
family and the absence of a dishwasher increased
the risk of developing hand eczema 4À (13).
Allergic Contact Dermatitis
Allergic contact dermatitis occurs on skin contact
with certain substances that act as contact allergens.
Individuals probably have a varying propensity
to develop contact allergy, though no definite
genetic markers have so far been identified. The
most significant factor in contact allergy development
seems to be the degree of exposure, comprising
concentration as well as the duration. To date,
over 3700 different substances have been identified
that can cause contact allergy (14). The most common
contact allergens are nickel, fragrances, rubber
chemicals, preservatives and colophonium
(natural rosin). These substances are present in our
everyday environments at home, at work and at
play. Only limited details are available regarding
the occurrence of contact allergy among the general
population. A Danish population-based study
showed that 19% of female subjects and 12% of
men gave at least 1 positive reaction on patch testing
(15). This would suggest that a difference between
the sexes does exist, though this requires
further investigation.