Outdoor and indoor air pollution (see Hazards) can
negatively affect the respiratory system in a number of ways, depending on the
pollutant, the concentration of the pollutant, the length of exposure, the
degree to which exposure includes multiple pollutants, and the susceptibility of
Air pollution has been linked with sinusitis, sinus headaches, congestion,
ear aches, colds and other other respiratory infections, structural damage to
the lung and/or airways, asthma, and lung cancer. Ozone, nitrogen oxides (NOx),
sulfuric dioxide (SO2), particulate matter and volatile organic chemicals (VOCs)
are the air pollutants most commonly linked to respiratory symptoms
in medical studies (Brunekreef, 2002).
Reactions to outdoor allergens, such as pollen and mold, are generally worse
when air pollution is also present (see Allergies).
Although air pollutants are most generally the pollutants associated with
environmentally induced or exacerbated respiratory disease, several other types
of exposure have been linked to lung cancer. In particular, water contaminated
with arsenic has been correlated with significantly increased rates of lung
cancer, even in nonsmokers.
In most instances, these pollutants cause an inflammatory response,
causing swelling and mucous secretions.
This environment is the perfect breeding ground for viral or bacterial
infections which often follow an increase in outdoor pollution levels. Upper respiratory tract infection symptoms include pain or pressure in
the facial sinus areas, headache, fever, nasal congestion and discharge, and sore throat.
Lower respiratory tract infections are characterized by fever, tightness in the chest, difficulty
breathing, and mucus-producing coughs. Respiratory flu, bronchitis and
pneumonia are all more common following increases in air pollution levels.
Exposure to second-hand cigarette smoke plays a major role in infections,
especially among children. According to the American Lung Association,
second-hand tobacco smoke causes 300,000 cases of lower respiratory infections
in children under the age of 18 months every year.
Because of the strong link between environmental triggers and asthma,
this topic is discussed separately (see Asthma).
ASBESTOSIS and SILICOSIS
These two environmentally induced respiratory diseases are generally
associated with workplace exposure (see
Workplace Hazards) to
asbestos or glass fibers (silica).
CHRONIC OBSTRUCTIVE PULMONARY
COPD generally results from cigarette smoking or second-hand
exposure to cigarette smoke. People with COPD are particularly
susceptible to air pollution.
By far the greatest cause of lung and other respiratory cancers is
cigarette smoking. Laryngeal cancer is elevated in carpenters. See