Page 11 - Healthy Living

23.Polyvinyl Chloride. Polyvinyl chloride (PVC) is a common low cost, lightweight but strong plastic commonly used in the pro-
duction of water and sewerage pipes, insulation for electrical cables, gutters, door and window frames, roof membranes and
moulding. It is also used in flooring, wall covering and ceiling material as vinyl tiles which are inexpensive and common in many
interiors such as offices, homes, hospitals, hotels and schools among others.

PVCs contain phthalates and dioxins which interfere with the production and normal activity of human hormones therefore
affecting the functions of thyroid, pancreas, adrenal, pituitary and reproductive glands.
They are also classified as carcinogens and can lead to cancer, liver dysfunction, vision failure, birth defects, chronic bronchitis,
asthma and genetic mutations.

The production of PVC and its disposal also exposes humans and the environment to toxic substances.

24.Lead is a heavy metal commonly found in roofing materials, paints, plumbing pipes. It is highly poisonous and is rapidly ab-
sorbed into the blood stream and simulates calcium enabling it to cross the blood-brain barrier.

It slowly accumulates in bones and soft tissues eventually destroying the nervous system. Close contact with lead also causes
blood disorders, brain disorders, blindness, reproductive health complications, damage to the kidneys and eventually death.
25.Wood treatments. Various treatments are applied to wood to preserve it and increase its life span. Most of the chemicals
used in wood treatment are water soluble. Creosotes are applied to wood as preservatives to prevent rot and come in a variety
of types depending on the material used to produce them such as wood tar creosote, coal tar creosote, oil tar creosote, and
water gas tar creosote. The coal-tar creosote is the most commonly used yet the most toxic since it directly causes cancer.

Exposure to large amounts of Pentachlorophenol, another wood preservative, can lead to harmful effects on kidneys, nervous
system, liver, immune system and can also cause cancer.

26.Halogenated flame retardants are chemicals incorporated in construction materials during manufacturing to slow down or
stop the spread of flames either by forming a protective film or by inhibiting chemical reactions that support combustion in
case of a fire break out.

When heated, these retardants degrade into toxic substances in gaseous form which then mix with dust and get into the body
through ingestion or inhalation.
They can cause disruption of hormones especially thyroid, adverse developmental problems in foetus and children, immuno-
toxicity, cancer and reproductive problems.

27.Cadmium. This is a soft malleable metal that is resistant to corrosion, insoluble in water and non-flammable when in solid
state.

It has been widely used on other metals especially steel as corrosion resistant plating. Its compounds have also been used to
stabilize plastic and to colour glass since they are available in red, yellow and orange pigments.

Cadmium fumes, highly soluble compounds or fine dust can cause pulmonary oedema (accumulation of fluids in the air spaces
and tissue in the lungs), pneumonitis (inflammation of lung tissue) and death.
High levels of exposure to cadmium have also been linked to prostate, breast and lung cancer.

28.Volatile organic compounds VOCs are naturally occurring or man-made chemicals with a low boiling point resulting in large
numbers of their molecules vaporizing and filling the surrounding air.

In building and construction, VOCs are commonly found in solvents, paint, plastics, synthetic fibres, adhesives and protective
coatings. Some of them such as formaldehyde which emanates from paint have boiling points as low as just -

VOCs usually cause irritation to eye and respiratory track, dizziness, memory impairment, damage to the kidney, liver and cen-
tral nervous system. Some have also been found to cause cancer in animals and humans.
29.Silica is a natural occurring substance found in stone, sand, concrete, tiles and bricks. It is absorbed in the body through in-