Environmental Engineering Reference
In-Depth Information
of dioxin release. Researchers have reported that the environmental concentration
of dioxin is above the concentration threshold in some aquatic environments [21].
PC is a clear plastic widely used in medicine as storage containers, in water bottles,
food cans and so on. BPA is a raw material used in PC and is found to leach into
foods and liquids stored in containers, a higher temperature increases the leaching
of BPA. BPA is a chemical that mimics oestrogen, a human hormone and BPA can
cause adverse side effects in humans. It stimulates prostate cancer cells and causes
breast tissue changes.
PET is wide used in packing materials for soft drinks, juice, water, beer, mouthwash,
detergents and so on. Antimony trioxide and bis (2-ethylhexyl) phthalate leach from
PET. These are associated with asthma and allergies in children, and they have an
effect on the kidneys, liver and spleen.
Polystyrene is widely used in Styrofoam containers, disposable cups, bowls, egg
cartons, food containers and compact disc cases. They tend to leach styrene, which
is an endocrine disruptor that mimics the hormone oestrogen (female hormone).
So it causes problems in reproductive developmental problems. Styrene is toxic to the
brain and nervous system, mostly to workers with long-term exposure.
In the marine environment plastic debris is the major cause of leaching of toxins that
include phthalates from PVC, nonylphenol (NP) (intermediate degradation product
of the nonylphenol ethoxylate class of surfactants) from polyoleins, brominated
lame retardants from urethane foam and BPA from PC and so on. NP is toxic to the
mammals and aquatic species.
1.7 Pollution in Beaches and Islands
Beach pollution is mainly caused by the debris washed onto the shores from the sea
because of natural phenomena such as tides, heavy rains, unexpected weather changes
as well as the human recreational activities carried out on the beach ( Figure 1.1 ).
The pollutants reach our beaches as a result of human activities carried out near
rivers, seas and man-made drainage, chemical manufacturing plants, spills from septic
tanks, and treatment tanks, waste from poultry or pig farms, waterprooing, paints
and seafood product waste caused by ishermen cleaning their products on the beach.
Waste generated from ships and small vessels also affects beaches and islands. So the
plastic debris found on the beaches are either from inland sources (transported by
river, drainage, wind or by human activities) or are directly from the ocean (brought
in by the tides). Floating, low-density debris can accumulate and can be transported
across huge distances. Most common plastic debris found at beaches includes: broken
 
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