Title:
Asthma,
allergies and air quality in Australia
Author: Rivqa
Rafael Berger
Category: Current
Affairs
Sometimes,
all I need is the air that I breathe’…to be a little bit cleaner.
Asthma and allergies such as hay fever is on the rise in many
countries. Many studies have shown that asthma and other lung
diseases are aggravated by pollutants emitted from cars, industry,
and cigarette smoke. So why aren’t we doing anything about
it?
Asthma
is a difficult disease to define. One common definition is
that asthma is a lung disease characterised by a ‘reversible
obstruction of airflow,’ characterised by wheezing and shortness
of breath.1 This can occur when
the airways are either more responsive than normal when dealing
with foreign matter such as pollen that makes its way into
the lungs.
Air
pollution aggravates asthma and other lung diseases.
Photo: Fabio
Imhoff |
It was
previously thought that the lungs remained healthy in between
asthmatic attacks, it has recently been shown that they can
progressively deteriorate, leading to permanent airway blockage
in the worst cases.1
Although
it is believed to be an inherited disease, at least in part,
the genetics involved are not yet fully understood.2
Risk factors include family history, parents who smoke, major
respiratory disease before the age of two, and exposure to
allergy causing compounds.3 Other
risk factors includes the nasty cocktail of carbon, nitrogen
and sulphur compounds, as well as heavy metals and particulate
matter that are derived from exhaust from cars, cigarette
smoke, home heating and cooking, and industrial waste. The
six main ‘criteria pollutants’ are particulate matter (PM),
sulphur dioxide, oxides of nitrogen (NOX), photochemical oxidants
such as ozone, carbon monoxide and lead.4
PM consists of small pieces of matter. PM causes respiratory
infections and irritations, as well as increasing the chance
of death from cardiorespiratory disease. Children and elderly
people with lung diseases such as asthma are particularly
vulnerable. Sulphur dioxide can irritate the throat and exacerbate
heart and lung disease, including asthma. These compounds
are especially dangerous when combined with PM. NOX can irritate
the eyes and increase respiratory disease, including asthma.
Ozone (O3) is produced when light energy reacts with high-energy
pollutants. Like NOX, it can irritate the eyes and throat.
It also intensifies respiratory disease and reduces exercise
capacity. Carbon monoxide (CO) is a potent toxin that can
cause a variety of symptoms, ranging from headaches to coronary
artery disease and death. Lead is produced was previously
found in leaded petrol, now banned. It can cause developmental
problems in children and hypertension in adults.
As most
of these compounds have similar sources, it is often difficult
to determine which is the most harmful. However, air pollutants
have certainly been shown to decrease quality of life, as
well as increasing hospital admissions and death. In Europe,
it is believed that deaths due to vehicle emissions are twice
as frequent as deaths due to car accidents.5
In New Zealand, 2% of deaths are caused by air pollution –
more than double the figure of deaths caused by HIV/AIDS or
malignant melanoma.
Although
there is no evidence to suggest that air pollution causes
asthma or hay fever, an Australian study has shown that air
pollution can worsen these conditions. This is especially
true for ozone; however it is difficult to separate these
results from the effects of other allergens such as pollen.6
However, other studies have suggested that air pollutants
may react with allergens such as pollen, thereby increasing
their detrimental effects on the lungs.7
Another
interesting factor that may cause or exacerbate asthma is
the weather. Reports of an increase in asthma attacks during
thunderstorms, in several parts of the world, has prompted
studies on the effects of meteorological phenomena on the
prevalence of asthma attacks. One study has shown that outflows
of cold air during storms may increase the concentration of
allergens in the air.8
Along
with The UK, the Republic of Ireland, and New Zealand, Australia
has one of the highest rates of asthma in the world. Asthma
costs the Australian public over $700 million, including medical
costs and loss of productivity. Several hundred people die
each year from asthma complications in Australia. Although
asthma is still on the rise in Australia, the death rate is
now decreasing.3
Given
the complex nature of asthma, and the variety of factors that
can cause or aggravate it, it may seem initially that little
can be done for asthma sufferers. However, by dealing with
each factor individually, at least initially, significant
steps can be made to ease the burden of asthma. In Australia,
many cases of asthma are inadequately treated. This can be
caused by ignorance, where the patient does not recognise
the symptoms of asthma and therefore does not seek treatment
at all, or by laxness after treatment in taking sufficient
medication.9 This problem can be
remedied by increasing education about asthma, a task that
is mainly being tackled by Asthma Australia, and its corresponding
state organisations.3
Something
else that might help asthmatics is a decrease in pollution,
although it is far from the only solution. As a society, we
can consider changing our driving habits in order to improve
our quality of life. In Australia and New Zealand, less than
5% of workers ride a bicycle to work, compared to 15-20% of
European workers. We go shopping in cars; take our children
to school in cars; drive to work in cars. Reducing the time
spent in cars would reduce the amount of emissions produced.
Industries such as mining, energy, and manufacturing also
need to consider the health effects of pollution.10
And perhaps then, asthmatics (or some of them, at least) will
be able to take a deeper breath…without coughing.
References
1.
Elias JA, Lee CG, Zheng T, Ma B, Homer RJ, Zhu Z. (2003)
New insights into the pathogenesis of asthma. Journal
of Clinical Investigation 111, 291-297.
2.
Haagerup A, Bjerke T, Schoitz PO, Binderup HG, Dahl
R, Kruse TA. (2001) Allergic rhinitis - a total genome-scan
for susceptibility genes suggests a locus on chromosome 4q24-q27.
European Journal of Human Genetics 9,
945-52.
3.
Asthma
Australia website
4.
Hinwood AL, Di Marco PN. (2002) Evaluating hazardous
air pollutants in Australia. Toxicology, 181-182,
361-366.
5.
Kunzli N, Kaiser R, Medina S, Studnicka M, Chanel O,
Filliger P, Herry M, Horak F Jr, Puybonnieux-Texier V, Quenel
P, Schneider J, Seethaler R, Vergnaud JC, Sommer H. (2000)
Public-health impact of outdoor and traffic-related air pollution:
a European assessment. The Lancet, 356,
795-801.
6.
Rutherford S, Simpson R, Williams G, Mitchell C, McCall
B. (2000) Relationships between environmental factors and
lung function of asthmatic subjects in south east Queensland,
Australia. Journal of Occupational Environ mental Medicine
42, 882-91.
7.
Glikson M, Rutherford S, Simpson R. (1995) The microscopic
and submicron components of atmospheric particulates occurring
during high asthma periods in Brisbane, Queensland, Australia.
Atmospheric Environment 29, 549-562.
8.
Marksa GB, Colquhounb JR, Girgisa ST, Hjelmroos Koskia
M, Treloarb ABA, Hansenc P, Downsa SH, Carc NG. (2001) Thunderstorm
outflows preceding epidemics of asthma during spring and summer.
Thorax, 56, 468-471.
9.
Woolcock AJ, Bastiampillai SA, Marks GB, Keena VA. (2001)
The burden of asthma in Australia. Medical Journal of
Australia 175, 141-5.
10.
Woodward AJ, Hales S, Hill SE. (2002) The motor car
and public health: are we exhausting the environment? Medical
Journal of Australia 177, 592-3.
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