Dementia and Air Pollution
first published: 8 August 2024
last updated: 21 October 2024
The purpose of this article is to illuminate
the issue of chronic smoke pollution
in residential villages in Queensland,
and to recommend a simple and effective solution.
Units tend to be located close to each other
in residential villages,
and typically there are no restrictions on the creation of smoke.
The prevention of smoke pollution
is usually given a low priority
because few people are aware of the
true scale of the health hazards
associated with it.
All of the many health hazards
associated with air pollution are relevant
to any discussion of public health and safety.
This article shines a spotlight on dementia,
a particular hazard of air pollution
that has so far managed
to fly under the radar of public awareness.
It has been known
to medical researchers for years
that air pollution can cause dementia.
The link between air pollution and dementia
should be of concern
to governments and healthcare providers,
and to all residents and administrators
of residential villages.
The Lancet
is one of the most prestigious medical journals in the world.
The work of The Lancet's standing commission on dementia
includes analysing the main risk factors for dementia.
Details of a recent update about dementia
from the commission
can be found in an
article in the "BBC News" website
published on 1 August 2024.
The main risk factors for dementia are:-
55% Inherited genes (there is not much that can be done about this)
7% Hearing loss (mid-life risk)
7% High cholesterol (mid-life risk)
5% Less education (early-life risk)
5% Social isolation (mid-life risk)
3% Depression (mid-life risk)
3% Brain injury (mid-life risk)
3% Air pollution (late-life risk)
2% Physical inactivity (mid-life risk)
2% Diabetes (mid-life risk)
2% Smoking (mid-life risk)
2% Hypertension (mid-life risk)
2% Visual loss (late-life risk)
1% Obesity (mid-life risk)
1% Excessive alcohol (mid-life risk)
total 100%
Scientific research has concluded that air pollution
causes more cases of dementia than
many other risk factors that are better known.
Maintaining an active brain is probably
the most wellknown strategy
for preventing the onset of dementia
and for slowing its progress.
Many of the risk factors for dementia,
such as social isolation or loss of hearing or loss of vision,
can lead to a reduction in brain activity.
Some risk factors however,
such as air pollution or high cholesterol or obesity,
do not seem to be associated with reduced brain activity.
The only way to minimise the number of cases of dementia
caused by these risk factors
is to minimise the factors themselves.
This means that air pollution needs to be reduced.
Based on the above figures
published by The Lancet about the causes of dementia,
simple calculations show
that more than 11% of preventable dementia cases
are caused by air pollution and tobacco smoking.
(The following calculations
are shown here to prove to disbelievers
that the 11% figure is correct.
People who have little time for arithmetic
can skip this section.)
45% of all dementia cases are preventable.
Unpreventable genetic factors account for the other 55% of cases.
3% of all dementia cases are caused by air pollution.
3 out of 100 of all dementia cases is 3 out of every 45 preventable cases.
Therefore 3 x 100 / 45 = 6.66% of preventable dementia cases
are caused by air pollution.
2% of all dementia cases are caused by tobacco smoking.
2 out of 100 of all dementia cases is 2 out of every 45 preventable cases.
Therefore 2 x 100 / 45 = 4.44% of preventable dementia cases
are caused by tobacco smoking.
6.66% + 4.44% = 11.10%
Therefore, whereas 2% + 3% = 5% of all
dementia cases (preventable and non-preventable)
are caused either by air pollution or by tobacco smoking,
this equates to more than 11%
of preventable dementia cases
being caused either by air pollution or by tobacco smoking.
Air pollution is endemic in parts of Queensland,
caused by the unrestricted use of
wood-burning heaters, mosquito coils, incinerators and firepits,
plus the usual vehicle exhaust emissions that occur everywhere,
as well as extensive bushfires and so-called "hazard reduction" burns
that disseminate smoke far and wide.
Air pollution can also be caused by the use of
agricultural and domestic pesticides and herbicides.
Most town-dwellers just accept this state of affairs,
while visitors to towns such as Hervey Bay
are surprised to find that,
depending on the direction of the wind,
they sometimes experience air pollution instead
of the fresh sea air that they had expected.
Many residents in retirement and lifestyle villages have dementia.
Empirical observations suggest
that more than half of the residents in some retirement villages
suffer from various forms of dementia.
In a hypothetical village
that has one hundred residents
who have dementia acquired
exactly in accordance with the risk factors shown above,
three residents would have dementia
as a result of air pollution
and two residents would have dementia
as a result of smoking.
The Lancet states that
air pollution is a late-life risk factor for dementia.
This seems to mean that elderly people are particularly at risk
of developing dementia as a result of air pollution.
Some elderly people insist that
they have to burn mosquito coils
during the warmer months of the year.
This is partly because there was little awareness
of the health hazards of smoke
when today's elderly people were young,
and partly because some elderly people are
more comfortable burning old-fashioned mosquito coils
rather than adopting modern methods of mosquito control
such as ultrasonic mosquito repellers
that do not cause health hazards
and are more effective than mosquito coils.
Taking the relatively small subset of village residents
who insist on burning mosquito coils frequently,
how many now have dementia
or will develop dementia?
In the light of The Lancet's findings,
it seems likely that
the answer to this question is far from zero.
Also, how many village residents
now have dementia,
or will develop dementia,
as a consequence
of inconsiderate neighbours
continuously burning mosquito coils?
Again, in the light of The Lancet's findings,
it seems likely that
the answer to this question is far from zero.
Also, village residents who are
constantly afflicted by smoke pollution
are likely to develop other health issues,
apart from dementia,
that will decrease their quality of life
and shorten their lives.
Residential units in retirement and lifestyle villages
are usually located close to each other.
Many units in retirement villages are actually joined together,
which further hinders the dispersal of smoke.
Some residents are unable to avoid
breathing mosquito coil smoke continuously
for several hours every day during the mosquito season
because some stubbornly inconsiderate residents
believe that they have an absolute right to continuously
burn mosquito coils.
After all, in Queensland this is what they had always done
before they moved into the close confines
of a residential village.
The problem persists because
some stubbornly negligent village managements
pretend that they can't see any problem.
See the article in this website titled
Mosquito Coil Smoke in Residential Villages in Queensland
for further information
about the health hazards of mosquito coils
and an analysis of why mosquito coils
are an inappropriate method
of preventing mosquito bites in residential villages.
The Lancet's dementia report shows
that it is possible to reduce the prevalence of dementia.
Cases of dementia that are preventable
include cases that are caused by air pollution
and cases that are caused by smoking.
Apart from reducing dementia,
it is possible to also reduce the prevalence of other illnesses
that are caused by smoke,
including asthma, bronchitis and cancer.
Air pollution can be a significant health hazard.
There are strong associations between air pollution and illness.
In a report titled
The Air that we Breathe
published by The Lancet in 2022,
it is stated that
"there is some evidence that even very low levels of air pollution can have negative health consequences."
In Queensland,
it is impossible to convince
some elderly people,
and also the managements of some residential villages,
that the smoke that is created
by the burning of mosquito coils is unnecessary
and causes substantial health hazards.
In the interests of public health and safety,
legislative reform is required.
The creation of smoke,
including smoke from mosquito coils,
ought to be prohibited in residential villages.
The Retirement Villages Act (Queensland 1999) states that
"residents must not unreasonably interfere,
or unreasonably cause or permit interference,
with the peace, comfort or privacy of other residents".
Repeatedly creating smoke
that causes a nuisance including serious health hazards
clearly breaches the intention of this clause.
The literal meaning of this clause
is imprecise because
there are many different interpretations
of the word
"unreasonably",
including interpretations that demonstrate
a profound ignorance of health and safety issues.
In relation to smoke pollution,
many people interpret the word
"unreasonably"
as having whatever unreasonable meaning
that they choose it to have.
It is a similar story for the Manufactured Homes Act.
To minimise the health hazards
caused by preventable air pollution in residential villages,
it is recommended that
relevant legislation should be amended
to explicitly state that village residents are prohibited
from deliberately creating any smoke.
For pragmatic reasons,
one exception would be necessary.
A blanket ban on the creation of smoke
in residential villages
would soon hit a stumbling block because
most tobacco smokers
would be unable to comply
due to nicotine addiction.
To accommodate this inescapable fact,
and also to help reduce the health hazards of smoking
without actually forcing any smokers to quit against their will,
it is suggested that the proposed prohibition
on smoke creation could
include an exemption that allows smokers in residential villages
to continue to smoke
for as long as they wish to do so,
provided that:
(a) they smoke only in places
where other residents cannot breathe the smoke.
(b) they participate in programs
that are designed to help smokers
to manage and reduce their smoking
(e.g. by attending support meetings once per month).
It is suggested that suitable programs
would require approval from village management,
and villages could have the option
of running their own programs.