Air pollution

Air Pollution

The challenges of air pollution legislation

• Challenges of Risk Assessment

• Economic consequences of over-regulation

• Geographic Variation• Fairness and the

Precautionary Principle

Modeling of Air Pollution

Emission

Transport

Deposition

ChemicalChanges

Major Air Pollutants

• Particulates• Nitrogen Oxides• Sulfur Oxides• Carbon Oxides• Hydrocarbons• Ozone

– Stratospheric– troposheric

• Lead (included with particulates in the text)• Air Toxics (hazardous air pollutants)

• Primary and Secondary Pollutants

• Mobile and Stationary Sources

• Smog• Photochemical Smog

Air Pollutant Sources (CA)

• Respiratory Disease– Emphysema– Bronchitis– Asthma

• Lung Cancer• Toxic Responses

– Mental impairment and Death– CO – reduction in blood’s ability to transport oxygen– Neurotoxic responses and effects on development

• Teratogenic and Mutagenic Effects– (less common for airborne pollutants)

Effects of Air PollutionHazard Identification and Dose Response

Effects of Air PollutionHazard Identification and Dose Response

• Loss of plant productivity• Damage to wildlife

populations• Corrode metals and

concrete

Issues associated with Exposure Assessmentfor outdoor air pollution

Exposure Assessment

Hazard CharacterizationEstablishment of standards

• Chronic vs. acute exposures• Sensitivity of the receptor• Precautionary principle?• Go through Risk Assessment

– Effects on human health– Effects on the ecosystem– Effects on buildings and

structures– Calculation of dosage– Inversions/Climatic

Effects

Establishment of Limits

• Maintain or improve conditions?• Who bears the burden?• Economic consequences of over-protection vs. the environmental

and health risks associated with the pollutants:

Technology to Control Air Pollution

• Stationary sources– Scrubbers…– Reduce pollution in material being burned– Higher stacks (greater dilution)– Hotter temperatures (more rapid dispersal)

• Mobile Sources– Catalytic converters– Cleaner fuels– Inspections

Legislation to Control Air Pollution

• Clean Air Act (1963, 1970, 1990)

• Common Pollutants– Criteria Pollutants

• Mobile Sources• Acid Rain• Toxic Air Pollution• Stratospheric Ozone

• Mobile Sources– Cleaner Cars– Catalytic converters– Lead and other toxins– Reformulated Gasoline– Low Sulfur Fuels– Alternative Fuels– Cleaner Trucks and Buses– Transportation Policies– Inspection and Maintenance Programs

Stationary Sources

Ozone Depletion

http://www.bom.gov.au/lam/Students_Teachers/ozanim/ozoanim.shtml

Acid Precipitation

Global Distillation Effect

Indoor Air Pollution