Airborne particles are a mixture of organic and
inorganic matter and can cause damage to your
health.
Their particle size determines the time they remain in
the air and their interaction with humans.
Particles above a diameter of 10mm can be trapped by the nose and
pharynx whilst anything smaller can penetrate to
your lungs.
If they do this they can cause the obstruction of your airways
and cause lung diseases.
Also some particles may be carcinogenic and therefore can cause
cancer.
For these reasons the monitoring of smaller particles in the
atmosphere is very important.
We usually concentrate on the particles likely to be deposited in
the lung, referred to as PM10s, which are come from a number of
sources.
Some are released directly into the environment by power stations,
factories and motor vehicles.
Vehicles contribute approximately 25% of particle emissions across
the UK but this figure is thought to be much higher in urban
areas.
Other sources of particles include those formed as sulphates and
nitrates from
sulphur dioxide
and
nitrogen dioxide and natural particles from spores and grains
of pollen.
Continuous monitoring of ambient dust levels is recorded in the
Portbury Dock area.
