1. Our Worsening Air Quality is Linked With Increasing Rates of
Heart Disease
While nobody likes the stench of foul-
smelling air or the uncomfortable side
effects that may accompany it, the
World Health Organization considers
even the most undetectable forms of air
pollution to be a major risk to health.
Pollution has long been linked to
respiratory problems, heart disease, and cancer. Recently, evidence
suggests there is even a strong association between poor air quality
and heart attacks and stroke.
Long-term Pollution Exposure – A Recipe for Heart Attack
A study led by a University of Michigan public health researcher
(and supported by the University of Washington) just revealed that
high concentrations of air pollution can lead to an increased
thickening of the inner two layers of the carotid artery. These are
two very important blood vessels that supply blood to the head, neck
and brain. What this means is that long-term exposure to air
pollution hardens these arteries, which in turn, leads to heart attack
and stroke. The research team also determined that a reduction in
exposure to pollution over a period of time meant a slower
progression of blood vessel thickness. The thickness of blood
vessels in human arteries shows just how much hardening exists in
the body, even in those who don’t seem to have any obvious signs or
symptoms of heart disease.
Researchers monitored over five thousand citizens from six different
U.S cities. They took age and lifestyle into consideration and
measured air pollution levels inside of the participant’s houses. They
were shocked to find that people who were exposed to high levels of
pollution were more likely to suffer a heart attack or stroke. The
participants in this study were monitored over three years, and will
continue to be monitored for seven more years. This will help

2. researchers distinguish between cases of clinical heart disease and
heart disease cases caused by long-term exposure to pollution.
The authors of this latest study say their findings help the scientific
community further the understanding of how air pollution may
cause increases in heart disease, heart attack, and stroke.
Even Moderate Pollution is Linked to Heart Attack and
Stroke
In the last year, the results of a decade long study were published in
the Archives of Internal Medicine linking moderate air pollution to
an increase in the risk of stroke. Stroke is the leading cause of long-
term disability in the United States. This study, conducted in
Boston, concluded that even moderate exposure to pollution
increases the risk of stroke by as much as 34 percent.
Almost two thousand hospital patients treated for stroke were
examined for this study. The onset of stroke symptoms in patients
was matched with hourly measurements of air pollution near their
homes. The research team was able to determine that peak pollution
exposure for stroke patients consistently occurred 12 to 14 hours
before the onset of the stroke. The study also determined that black
carbon and nitrogen dioxide, both associated with automobile
traffic, were heavily linked with stroke risk. Since the moderate
pollution testing was only conducted in Boston, which is considered
to be fairly clean, the researchers promote the need for similar
studies to be carried out in other U.S cities.
The Air Quality in Your Community – What To Look For
The air quality index tells you how clean or unclean your air is, and
what health concerns are associated with different levels of
pollution, including heart disease and stroke. In the United States,
the Environmental Protection Agency (EPA) sets the daily air
quality index, represented by six color levels. The most common are
green (good), yellow (moderate), and orange (unhealthy for

3. sensitive groups). On rare occasions, the air quality has been listed
as red, which is unhealthy for most citizens. If you already have an
existing health condition, it is best to avoid going outside on orange
or red days.