Civil Engineering Reference
In-Depth Information
Synthetic resins and some non-solvent based pollution
Formaldehyde adhesives
Urea, melamine, phenol, resorcinol and phenol-resorcinol formaldehyde adhesives all
represent a risk in the working environment. Formaldehyde can be emitted, for example,
from a plywood press. Pure phenol is poisonous and can seriously damage health after
long periods of exposure. Phenol and formaldehyde are also poisonous if they come into
contact with water. Formaldehyde is not as problematic as phenol, as it quickly oxidizes
to formic acid and then carbonic acid. The Academy of Science in the Czech Republic
blame dead forests on phenol working with metals.
In buildings with products glued together with formaldehyde adhesives there will be
emissions of formaldehyde. The adhesive with the weakest binder is urea formalde-
hyde, which therefore has the highest emissions. Relatively small doses of formalde-
hyde can give acute symptoms of irritation in the eyes, itching in the nose, a dry throat
and sleep problems. This can, in the long run, develop into serious problems in the
inhalation routes. The substance is also registered as carcinogenic and a cause of aller-
gies.
Epoxide adhesive
Fresh epoxide, which is the main constituent of epoxide adhesive, is one of the most
effective allergens that exists. At places of work exposed to it, up to 80 per cent of
the work force have developed epoxy eczema. Epichlorhydrin, which is part of the
adhesive, is registered as carcinogenic and allergenic. Epoxide adhesive also con-
tains alkylphenols and bisphenol A compounds, which are suspected environmental
oestrogens. The material is also soluble in water and is poisonous and corrosive to
organisms in water in low concentrations. Hardened epoxide adhesive is chemically
stable.
Polyurethane and isocyanate adhesive
Isocyanates can easily cause skin allergies and asthma. They can also cause a degree of
sensitivity and mucous membrane damage such that later exposure can induce asthmatic
attacks, almost totally independent of the degree of exposure. The problems are greatest in
industry and on building sites, but there can also be emissions from inside a building where
the adhesive has not completed its reaction.
Synthetic contact adhesives
Chloroprene and styrene butadiene adhesive are the main synthetic contact adhesives in
common use. Butadiene is registered as carcinogenic. Styrene is mainly a nerve poison,
but is suspected of being carcinogenic and mutagenic. Chloroprene in chloroprene adhe-
sive is considered responsible for reducing fertility and causing deformities and sperm cell
damage. These effects are most likely to occur in the working environment. In a complet-
ed building there can, however, be emissions from adhesives that have not completed
their reactions.
Acrylate adhesive
This can emit excess monomers in a completed building, which can increase the fre-
quency of over-sensitivity and allergies.
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