This document discusses the relationship between air pollution and asthma. It begins by defining asthma as a chronic respiratory disorder characterized by sensitive and inflamed airways that overreact to certain air pollutants. It then examines the effects of specific air pollutants like nitric oxide, ozone, and particulate matter on asthma pathology. Nitric oxide can have dual effects depending on its quantity, type of enzyme involved, and location of release. Ozone production is increased by nitrogen oxides and volatile organic compounds reacting with sunlight. Particulate matter from sources like burning fuels exacerbates asthma by promoting allergic inflammation and increasing reactive oxygen species, which cause further tissue damage and symptom amplification.

1. AIR POLLUTION & ASTHMA
P R E P A R E D B Y : J O R D A N T Y S O N

2. ASTHMA: WHAT IS IT?
A chronic respiratory disorder
Sensitive and inflamed airways
 Airways overreact to certain air pollutants
 Bronchial tube tightens  less airflow to lungs
 Increased mucous production  narrows airways
 Shortness of breath, chest tightness, coughing, wheezing

3. COMPARE AND CONTRAST

4. SIMPLE STATISTICS ON ASTHMA
Affects ~ 3 million people in USA ; increasing
Prevalence in urban areas > rural areas
Due to combination of genetic predisposition factors + environmental exposure to
airway irritants
Air pollution: sulfur oxides, nitric oxides, ozone, particulate matter

5. NITRIC OXIDE
Atmospheric pollutant
 Cigarette smoke
 Vehicles
Dual effects in asthma pathology
 Quantity
 Type of enzyme
 Location of release

6. DUAL EFFECTS OF NO IN ASTHMA PATHOLOGY

7. OZONE
 In the troposphere, sunlight
reacts with:
• Ozone precursors (ie. NOx,
such as NO2)
• Volatile organic
compounds(VOC)s
 Increased ozone production
NO2 + Sun UV  NO + O
O2 + O  O3

8. PARTICULATE MATTER
Sources  Industrial processes, wood combustion & fossil fuels, construction,
wild fires, windblown dust, etc.
• Sulfur and nitrogen oxide
are contributors
Composition  bioaerosol
components, metals,
organic molecules,
and elemental carbon

9. PARTICULATE MATTER
Increased PM  increased emergency room visits and medication use by
asthmatics
Promotes sensitization leading to:
 Allergic inflammation & airway hyper-responsiveness
Samples with transition metals are the most capable of exacerbating
asthma
 Promotes ROS formation  epithelial injury  airflow limitations/asthma
symptoms
 Increased peroxidation products in lungs, blood, and urine of asthmatic
subjects

10. SUMMARY
People with asthma have very sensitive and inflamed airways, which tend to
overreact by constricting and/or overproduce mucous when certain substances
in the air are inhaled
Symptoms: shortness of breath, chest tightness, coughing, and wheezing
Many asthma medications are iNOS inhibitors
Ozone production is elevated by the presence of ozone precursors and volatile
organic compounds (VOCs)
Particulate matter (PM) sources  anthropogenic (burning fossil fuels & wood)
and natural (windblown dust and wild fires)
PM samples with high concentrations of transition metals are the most capable of
exacerbating existing asthma and sensitization.
Transition metals lead to generation of ROS, which promote allergic reactions,
inflammation, and tissue damage leading to an amplification of symptoms