Raising Pet Birds - Can it be Made Safer?

Abstract

The doctors were stumped. Lung
cancer was on the increase with each
passing year. Yet smoking of cigarettes
was diminished. Stricter pollution
standards were imposed resulting
in cleaner air. And levels of asbestos, a
known carcinogen, were much
reduced after it was banned from
home insulation. Why were there so
many new cases of lung cancer?
The solution to this conundrum was
revealed upon analysis of hospital
data in three countries in Europe -
The Netherlands, England and Belgium
- countries that had a disproportionately
high number of cases of
lung cancer, and were increasing at a
faster rate than their neighbors. What
did these nations have in common?
In 1987, a group of Dutch lung specialists
published a survey of lung
cancer patients in four hospital centers
at The Hague, The Netherlands. They
found that there was a sixfold increase
in lung cancer in patients who kept
birds. Coincidentally, approximately
70o/o of tropical bird aviculturists in
Europe are located in The Netherlands,
England and Belgium.
Two additional reports from abroad
have recently appeared in the respected
British Medical Journal (October
24, 1992) which support the connection
between aviculture and lung
cancer which should raise concern
among everyone who keeps birds.
A study from Germany found that
chronic exposure to birds in the previous
five years increased the likelihood
of lung cancer almost twice when
compared to individuals who had no
such exposure. The risks increased
with each year so that lung cancer was
three times as likely after ten years of
bird keeping. A group of British doctors
found a fourfold increase in risk
of lung cancer associated with raising
pigeons.
What is it about raising birds which
increases the risk of developing lung
cancer? No one knows for sure but
there are a number of possible reasons. 

People who keep birds are
inhaling excess dust particles and
feather fragments which provoke a
reaction in human lungs. There are
cells in the lungs called macrophages,
whose job is to help remove foreign
particles and fight off infection, and
which lose their normal function
when constantly exposed to these
substances. As a consequence, there
is less protection for lung tissue
against infection and foreign particles.
Moreover, substances are released by
macrophages upon exposure to particulate
matter which cause an allergic
reaction and scarring of lung tissue.
Scarring (pulmonary fibrosis) is recognized
as a factor in causing lung
cancer.
There remain many unanswered
questions about birdkeeping and lung
cancer. Does the risk vary depending
upon whether one is raising parrots,
budgerigars, canaries or finches - or
whether one raises large numbers of
birds at one time? Does it make a difference
whether birds are raised
indoors or out? More studies are necessary
to find these answers.
Is there anything that aviculturists
can do to reduce or minimize the risk?
Cigarette smoking remains the major
cause of lung cancer. Smoking produces
many of the pathologic changes
in the lungs described above and
although the risks of bird keeping can
be shown to be independent of smoking
- the combination probably is
additive. So if you keep birds, don't
smoke! Since passive exposure to
smoke also increases the risks of lung
cancer, discourage anyone else in
your family from smoking. Furthermore,
it would be prudent for those of
us who raise birds to wear an inexpensive
paper surgical mask when in
contact with the birds (the masks can
be purchased in quantity at any pharmacy)
to cut down on exposure to airborne
particles. A vi culture has many
joys and many challenges and, with a
few precautions, should not be hazardous
to your health. •

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