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Asbestos is extremely dangerous
to man’s health.
Asbestos
from the Greek àsbestos, meaning "inextinguishable"
or amianthus from the Greek amiantos
meaning “incorruptible” is a silicatebased
mineral that can separate into highly flexible fibers
that are resistant to heat and chemically inert..
As its thermal insulating properties made it very
desirable for building materials, asbestos was used
extensively in the past in insulation and composite
materials (asbestos cement). However, if inhaled
asbestos fibres are carcinogenic. Today, as we are
aware of the dangers of asbestos exposure, special
precautions must be taken when removing and disposing
of asbestoscontaining material.
Natural asbestos is found in two varieties:
SERPENTINE (curved
fibres) Chrysotile (white amianto)
AMPHIBOLE
(straight fibres) Anthophyllite, Actinolite, Amosite
(brown asbestos), Crocidolite (blue asbestos), Tremolite.
Asbestos is a health hazard if its fibres are released
to the air or become airborne and then inhaled.
The human organs affected by exposure to asbestos
are the lungs, the pleura, the pericardium and the
peritoneum. Exposure to asbestos can cause a chronic
lung disease or cancer called “asbestosis”,
whereas “mesothelioma” is a form of
cancer that affects the pleura.
Health risks from asbestos clearly increase with
increased exposure, although some asbestos-related
diseases can develop in people with only short-term
exposure. Nonoccupational exposure to asbestos is
a health risk as well; in fact, all persons residing,
working or frequenting buildings constructed with
asbestoscontaining materials are at risk, as fibers
may be released and inhaled, and eventually penetrate
the lungs.
The amphiboles, characterized by rigid fibres, are
considered the most hazardous asbestos type. Past
asbestos exposure still kills roughly one thousand
persons each year. It is believed that this number
will continue to increase over the next decade.
There is usually a long latency period between exposure
to asbestos and the onset of the disease. This can
vary from 15 to 60 years. Asbestos-related diseases
will only be wiped out when exposure to asbestos
is eliminated or reduced to a minimum.
Main application for asbestos:
Fabrics: blankets, fire-retardant clothing, cushions,
ropes, gloves, trivets, ironing boards, etc...
Sheets: seals, pipe insulators, cardboard, etc.
In loosely bound materials: wall panels, cladding
for train carriages, etc...
In firmly bound materials: roof covering, tubs,
piping, chimneys, seals, brake linings, vinyl sheet
flooring, clutch facings, etc...
Since
1994, Italian Law 257/92 prohibits the use and sale
of asbestos-containing materials. |
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| Chrysotile |
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| Crocidolite |
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| Chrysotile fibres |
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