Airport Air Quality:Health Effects

Michael T. Kleinman

University of California, Irvine

BackgroundAirport pollution sources consist of aircraft

and on-ground off-road airport equipment.Airports rank among the top 10 industrial air

pollution sources in their cities.Emissions from airports include fine particles,

hydrocarbons, nitrogen oxides, carbon dioxide, and carbon monoxide.

On-road vehicle traffic (automobiles and trucks) also contribute to community exposures.

BackgroundOne 747 arriving and departing from an

airport emits about the same amount of particles as a car driven over 5,600 miles.

It emits about the amount of nitrogen oxides as a car driven nearly 26,500 miles.

Aircraft pollution accounts for about 1.4% of all air pollution from mobile sources (EPA).

Aircraft account for up to 4% of global warming gases (carbon dioxide and nitrogen oxide).

Pollutant Health Issues: Hydrocarbons

Toxic air contaminants Benzene Solvents Aldehydes 1,3 butadiene

Contribution to formation of Ozone

Health and Welfare Effects of Toxic Air Pollutants

Effect Quantified Unquantified Other

Human Health Cancer Mortality Non-cancer Effects Neurological Respiratory Reproductive Immunological Reproductive and

developmentalHuman Welfare Decreased income

because of decreasedphysical performance

Decreased recreationopportunities

Ecological Effects on wildlife Effects on plants Loss of biodiversity

GlobalClimate

Other Welfare Visibility Materials Damage

Pollutant Health Issues: Nitrogen Oxides

Emitted by all combustion sources.Human Health Effects

Respiratory Illness and Increased Susceptibility to infections.

Increased airway responsiveness. Decreased pulmonary function. Immunological changes.

Pollutant Health Issues: Carbon Monoxide

Product of incomplete combustion.Human Health Effects

Hospital Admissions (Congestive heart failure) Decreased time to onset of angina. Increased susceptibility to abnormal heartbeats. Possible developmental effects.

Pollutant Health Issues: Particulate Matter

Airport-related particles contain toxic constituents and are of a size that can readily penetrate to the deep lung.

Airport-related particles can remain airborne for long periods of time and therefore can exert effects over large geographical distances.

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Low Levels of Particles AlterVisibility

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Particles Vary in Size and Shape

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Acute and Chronic Effects of PM

• Mortality

• Bronchitis

• Hospital admissions - Chronic respiratorydiseases

• Respiratory other than chronic bronchitis

• Cardiovascular Effects

• Emergency room visits for asthma

• Altered host defense mechanisms

• Lower respiratory illness

• Cancer

• Upper respiratory illness

• Shortness of breath

• Respiratory symptoms

Understanding Particle-InducedHealth Effects Begins With

Understanding the Lung• The human lung is a

complex, branchingstructure.

• The structure is alsocomplex at the cellularlevel .

• This complexityresults in differentialsensitivity to particles.

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Particle Size Influences Deposition

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Airways are Complex Structures

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Soluble Particles Clear Quickly ButInsoluble Particles Are Retained For

Long Periods

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Sensitive Human Populations

• Asthma

• COPD

• Cardiac Patients

• Elderly

Exposure Can Lead to Effects

• Particles can bedelivery vehicles fortoxic compounds.– Constituent

– Adsorbed

• Compounds can haveeffects in lungs, butcan also actsystemically.

Role of TNF in Particle-Induced Responses

Evidence of Oxidative Stressin Lungs of Rats

A B•Terminal bronchiolesstained fornitrotyrosine

•Note intensestaining associatedwith inflammatorycells in Panel B.

•Note unstainedalveolar epithelium incontrol (Panel A).

Particles Don’t Just Affect the Lung

Conducting airways and gas exchange region of thelung can be injured by inhaled particles.

Inhaled particles can also cause allergies

Particle dose is increased by exercise.

100% of circulating blood passes through the lung.

Thus, toxic components delivered by inhaled particles canhave effects on other organs.

Hemodynamic Changes After ParticleExposures

Control < 0.2 0.7 1.8-15

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Particle Size DeterminesDeposition Fractions and Sites

• Thoracic depositioncan be estimated usingappropriate modelsafter correcting fornasal deposition.

• Of the aerosol thatpenetrates through theURT, most deposit inthe gas exchangeregion.

0.1 1 10

Par ticle Size (æm)

0.00

0.06

0.12

0.18

0.24

0.30

% D

epos

ited

Figure 2. Estimated Regional Particle Deposition in the Rat

Total

Bronchial

Pulmonary

Particle Mass and Actual DoseMay be Important

• We can estimatedeposition fractionsusing models.

• We can estimateventilation fromobservations or scalingmodels.

• We can calculate adeposited dose.

0 5 10 15 20 25

Particle Mass (µg Deposited in Rat Pulmonary Region)

-10

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Syst

olic

Pres

sure

(% C

hang

e Fr

om C

ontro

l)

Figure 3. Change in Blood Pressureas a Function of Deposited Particle Mass

Conclusions• “The dose makes the poison” - Paracelsus• Particle size is an important parameter for

understanding health effects.

• Particle size clearly influences dose.

• Particles of the size that are emitted by airport-relatedsources are those that most likely associated withprovoking health effects in humans.