Exhaust from all combustion engines combine to produce
local adverse effects on the health of car users and all innocent bystanders.
Cities have become islands of toxic chemicals from the unrestrained use of
vehicles burning fossil fuels.
Air pollution, both indoor and outdoor, is a significant cause of health
problems worldwide. Urban and rural outdoor environments contain allergens,
irritants and toxins that can reduce the quality of life and cause disease.
Inhaled air pollution is directed at the the nose, throat and lungs. The exposed
airway allows hazardous pollutants to enter the body and all tissues are
Air pollution was first noticed as problem of city
dwellers, poisoning themselves, but more recently, air pollution is acknowledged
as a problem of global significance. The tolerance for environmental destruction
is ancient and human history is littered with civilizations that failed because
humans exploited natural resources and spoiled their own nest. Humans adapt
easily to deteriorating conditions and will persist in following daily routines
even when air pollution is severe, traffic is congested, water and food supplies
are at risk, and social order is unstable.
Fine-particulate air pollution is known to contribute to cardiovascular and
lung disease, increasing the risk of heart attacks and a heart-related death.
Researchers at Brigham Young University and Harvard School of Public Health
compared changes in air pollution from 1980 to 2000 with residents’ life
expectancies. They concluded that a reduction in air pollutants in 51 U.S.
cities between 1980 and 2000 added an average of five months to life expectancy.
Residents in cities that made the most significant improvements in air quality,
such as Pittsburgh, PA, lived almost 10 months longer. For every microgram
per cubic meter decrease in fine-particulate air pollution, life expectancies
rose by more than seven months.
Airborne chemicals contaminate food and
water. Airborne chemicals contaminate food and water sources. Airborne chemicals
are ingested; they collect in the nose and throat and are swallowed, often in
mucus that attempts to protect exposed surfaces. Airborne chemicals entering the
digestive system include well-known toxins such as pesticides, organophosphate,
PCBs, dioxin, arsenic, cadmium, lead, and mercury. In addition occupational
exposures to airborne pathogens can be intense and can cause cancer.
Driving a car is the most polluting act an average citizen
commits. Cars and trucks have two opposite personalities. One is friendly and attractive
the other is destructive and can be lethal. Emissions from passenger vehicles
are going up in Canada and the US despite attempts to make engines more fuel
efficient and despite the addition of antipollution devices. The main reason is
that cars are getting bigger and pick-up trucks and sports vehicles are often
replacing smaller, lighter passenger cars. The average new vehicle in 2001
consumed more fuel that its counterpart in 1988. In the USA in 1987 cars
averaged 25.9 miles to the gallon. Fuel efficiency dropped to 24.6 miles/gallon
by 1998 and is dropping further as larger vehicles replace smaller ones.
Air pollution is associated with increased hospital
admissions for cardiovascular diseases with increases in acute morbidity and
mortality. D'Ippoliti et al studied 6531 patients in Rome who were
hospitalized for acute myocardial infarction from January 1995 to June 1997. Air
pollution data were taken from 5 city monitors. Positive associations were found
for total suspended particulates, NO2 and CO. The strongest and most consistent
effect was found for total suspended particulates.
Increases in fine particulate matter air pollution
increase the risk for myocardial infarctions, strokes, and heart failure. For
example, particle deposition in the lungs activates the sympathetic nervous
system and triggers the release of systemic pro-inflammatory responses. Brook
and Rajagopalanb stated: "Higher circulating levels of inflammatory cytokines
cause vascular endothelial dysfunction and activation of vasoconstrictive
pathways while blunting vasodilator capacity. At the molecular level, the
generation of oxidative stress with the consequent up-regulation of redox
sensitive pathways appears to be a common mechanism of these pro-hypertensive
responses. Due to the ubiquitous, continuous and often involuntary nature of
exposure, airborne fine particles may be an important and under-appreciated
worldwide environmental risk factor for increased arterial Blood Pressure.
vovKlot et al conducted a multicenter study involving
22,006 survivors of a first myocardial infarction in European cities. Air
concentrations of nitrogen dioxide, carbon monoxide, ozone, and particles
(PM10) were measured: 6655 cardiac readmissions were observed. Cardiac
readmissions increased in association with same-day concentrations of PM10.
Effects of similar strength were observed for carbon monoxide, nitrogen dioxide
and ozone, They concluded that air pollution is associated with increased risk
of hospital cardiac readmissions of myocardial infarction survivors in 5
Simkhovich et et al confirmed that epidemiologic studies
show that increased levels of air pollutants are positively associated with
cardiovascular morbidity and mortality. They stated:`nhalation of air
pollutants affects heart rate, heart rate variability, blood pressure, vascular
tone, blood coagulability, and the progression of atherosclerosis. Major
mechanisms of inhalation-mediated cardiovascular toxicity include activation of
pro-inflammatory pathways and generation of reactive oxygen species. Although
most studies focus on the influence of systemic effects, recent studies indicate
that ultrafine particles may be translocated into the circulation and directly
transported to the vasculature and heart where they can induce cardiac
arrhythmias and decrease cardiac contractility and coronary flow.`