Harmful Effects of Air Pollution Video Lecture - Class 8

in this video we are going to learn
about the effects on our health from a
range of air pollutants if you live in
the city you may already be aware of the
effects of hair pollution on your health
you may already have had some breathing
discomfort or painful eyes and ones that
we'll be focusing on in this video are
particulate matter called pms ozone o3
nitrogen oxides and sulfur dioxide more
often than not these pollutants exist
there's a direct result of human
activity one such human activity is the
burning of fossil fuels in power
stations or cars particulate matter is a
mixture of sulfates nitrates ammonia
sodium chloride carbon mineral dust and
water it consists of a complex mixture
of solid and liquid particles of organic
and inorganic substances suspended in
the air these particles are identified
according to their aerodynamic diameter
as either pm10 particles with an
aerodynamic diameter smaller than 10
microns or PM 2.5
these have aerodynamic diameter smaller
than 2.5 microns in comparison the
average size of a human hair is 60
microns PM 2.5 s are more dangerous
since when inhaled they may reach deep
into the lungs and interfere with gas
exchange the health effects of
particulate matter are felt in both the
developed and developing world chronic
exposure to particles contributes to the
risk of developing cardiovascular and
respiratory diseases typically asthma as
well as lung cancer ozone o3 absorbs
harmful UV rays from the Sun in the
upper atmosphere and can help prevent
the increase risk of skin cancer however
ground-level ozone causes problems it
does so
photochemical reaction which is
triggered by the absorption of light the
reactions between nitrogen oxides and
volatile organic compounds lead to the
formation of a photochemical smog and
ground ozone you see this more often in
the summer and it can appear as an
orange brown haze over a city this smog
include in the ground ozone causes
breathing problems can trigger asthma
attacks and lead to lung disease next
nitrogen dioxide emissions come from
cars and factories where fuels are
combusted you may recall oxygen forms
about 21% of our atmosphere whilst
nitrogen forms 79% in a hot engine a
tiny amount of nitrogen atoms join with
oxygen atoms to form mixtures of
nitrogen oxides called NMX
studies have proven that there is a
causal relationship between the symptoms
of bronchitis a respiratory disease been
seen in children with asthma as a result
of long-term exposure to this pollutant
finally there is sulphur dioxide can you
think how this chemical might be formed
pause the video and continue and ready
the correct answer is that any sulphur
combusted in the presence of oxygen
typically coming from fossil fuels which
naturally contain tiny amounts of sulfur
and also the smelting of mineral ores
lead to the formation of sulfur dioxide
in turn these pollutants affect the
respiratory system and cause irritation
of the eyes if you breathe this in
you're more likely to cough or scream or
mucus and will be a higher risk of
developing chronic bronchitis in summary
all are causing unnecessary deaths
especially where the emissions of these
pollutants can be avoided for the use of
catalytic converters in cars and by
scrubbing of power station gases
you