Environment Health
Air Pollution
Quri R. Wygonik, M.S.
HEAL 3500: Environmental Health
Spring 2018
3/14/18
Learning Objectives
By the end of today’s lecture, students should be able to:
Identify potential sources of air pollution
List the 6 EPA categories of common air pollutants
Describe the National Ambient Air Quality Standards (NAAQS)
Differentiate and provide examples of primary and secondary air quality standards
Identify sources (natural, industrial, other) of each common air pollutant category (x6)
Describe the environmental and human health impacts of each common air pollutant category (x6)
Small Group Brainstorm!
Please get into groups of 3-4 and brainstorm potential sources of air pollution
Elect someone to share with the class
Air pollution can be do to several sources
Potential sources of air pollution:
Stationary sources
Factories
Power plants
Dry cleaners or other small businesses
Mobile sources
Cars and trucks
Busses
Trains
Planes
Naturally occurring sources
Dust/windblown natural contaminants
Volcanic eruption
Air quality can be compromised due to air pollutants
(EPA) 6 categories of common air pollutants:
Ozone
Particulate Matter (PM)
Carbon Monoxide (CO)
Nitrogen Oxides/Nitrogen Dioxide (NOX/NO2)
Sulfur Dioxide (SO2)
Lead
(EPA) Ground-level ozone and PM are most harmful
(EPA) Primary standards:
Permissible level determination based on human health risk
(EPA) Secondary standards:
Permissible level determination based on environmental and personal property damage risk
National Ambient Air Quality Standards (NAAQS)
Clean Air Act (last amended, 1990)
Requires EPA to set NAAQS for pollutants considered harmful to public health and environment
Clean Air Act identifies two types of national ambient air quality standards:
Primary standards: public health protection, including protecting health of "sensitive" populations such as asthmatics, children, elderly
Secondary standards: public welfare protection, including protection against decreased visibility, damage to animals, crops, vegetation, buildings
Category 1: Ozone
Ozone: not directly emitted
Formed when nitrogen oxides (NOX) and volatile organic compounds (VOCs) react in presence of sunlight
Environmental/ecosystem effects of ozone:
Affects sensitive vegetation (trees and plants during growing season)
Increases susceptibility of sensitive plants to disease, damage from insects, effects of other pollutants, competition, harm from severe weather
Loss of species diversity, changes to habitat quality , changes in water and nutrient cycles
When ozone enters leaves of plants:
Interfere with ability of sensitive plants to produce/store food
Damage leaves, harm appearance
Human health impacts of ozone
Sensitive population(s):
Children and elderly
Individuals with existing lung disease/complication
Anyone active outdoors or outdoors laborers
Ozone exposure can lead to:
Difficulty breathing (deep)
Shortness of breath and pain (when deep breathing)
Coughing and sore/scratchy throat
Inflammation and damage to airways
Aggravation of existing lung diseases (asthma, emphysema, chronic bronchitis)
Increased frequency of asthma attacks
Increased susceptibility of lungs to infection
Continued lung damage (even after symptoms ease or disappear)
Category 2: Particulate Matter (PM)
PM: complex mixture of extremely small particles and liquid droplets
Acids (nitrates and sulfates)
Organic chemicals
Metals
Soil and dust particles
Size of particles linked to human health and environmental outcome
Inhalable coarse particles (2.5-10 micrometers in diameter)
Critical health concern: pass through nose and throat to lungs
Fine particles (2.5 micrometers in diameter or smaller)
Directly emitted from forest fires, or form when gases emitted from power plants, industries, automobiles react in air (secondary particles)
Environment and human health impacts of PM
Environmental impact:
Haze resulting from PM accumulation of fine particles
Fine particles visible in sunlight (fog effect)
Degrades visibility in scenic areas (worse in humid conditions)
What other issues can result?
Increased acidity in water, change in nutrient balance in water and soil, forest and crop damage, threat to ecosystem diversity
PM exposure can lead to:
Premature death in people with existing heart or lung disease
Nonfatal heart attacks
Irregular heartbeat
Aggravated asthma
Decreased lung function
Increased respiratory symptoms (airway irritation, coughing, difficulty breathing)
Category 3: Carbon Monoxide (CO)
CO: colorless, odorless gas emitted from combustion processes
Majority of CO emissions to ambient air come from mobile sources, usually in urban settings
(1980-2013): 84% decrease in CO concentration (ppm) in air, significantly improved air quality
Human health impacts of CO
Human health impact:
Reduces oxygen delivery to body's organs (heart and brain) and tissues
At extremely high levels, can cause death
Exposure can reduce oxygen-carrying capacity of blood
At-risk: people with heart disease (already have a reduced capacity for pumping oxygenated blood to heart)
Myocardial ischemia (reduced oxygen to heart) and angina (chest pain) when exercising or under increased stress
Short-term exposure of concern for at-risk
Category 4: Nitrogen Oxides (NOX)
NOX: highly reactive gasses
Nitrogen dioxide (NO2) – indicator of NOX group
Nitrous acid
Nitric acid
NO2 forms quickly from car, truck, bus, power plant, off-road equipment emissions
Contributes to formation of ground-level ozone and fine particle pollution
Similar environmental effects
Name a few?
Human health impacts of NOX
Human health impact:
Short-term NO2 exposures (30 min to 24 hours) linked with adverse respiratory effects
Airway inflammation in healthy people
Increased respiratory symptoms in people with asthma
NOX react with ammonia, moisture, other compounds to form small particles (PM)
Respiratory disease (emphysema and bronchitis)
Aggravate heart disease, premature death
Ozone formation (reacts with sunlight)
Similar health effects
Name a few?
Category 5: Sulfur Dioxide (SO2)
SO2: Highly reactive gasses
Largest sources of SO2 emissions from fossil fuel combustion at power plants (73%)
Other industrial facilities (20%)
Smaller sources of SO2 emissions from industrial processes (extracting metal from ore, burning high sulfur containing fuels)
Acid rain:
Leads to pH imbalance in sensitive water and soil systems
Aluminum released from soil due to acid, highly toxic to aquatic life and on-land biodiversity
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Human health impacts of SO2
Human health impact:
Short-term SO2 exposures (5min to 24 hours) linked with adverse respiratory effects
Bronchoconstriction healthy people
Increased respiratory symptoms in people with asthma, elevated ventilation rates
SO2 (sulfur oxides, SOX) react with other compounds to form small particles (PM)
Respiratory disease (emphysema and bronchitis)
Aggravate heart disease, premature death
Direct and indirect human health effects due to acid rain:
Name a few?
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Category 6: Lead
Lead: metal found naturally in environment and in manufactured products
Major sources of lead emissions historically from on-road motor vehicles (cars, trucks) fuels and industrial sources
EPA's regulatory efforts to remove lead from on-road motor vehicle gasoline
(1980-1999): Emissions of lead from the transportation sector declined by 95%
(1980-1999): Total lead emissions declined by 94%
Major sources of lead emissions to air today: ore and metals processing, piston-engine aircraft operation (lead-based gasoline)
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Environmental impacts of lead
Environmental impact:
Persistent in environment, accumulates in soils and sediments
Deposition from air sources, direct discharge of waste streams to water bodies, mining, erosion
Ecosystems near lead point sources (known source) adversely affected:
Losses in biodiversity, changes in community composition
Decreased growth and reproductive rates in plants and animals
Neurological effects in vertebrates
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Human health impacts of lead
Human health impact:
Exposure pathways: air, ingestion (drinking water, food, soil, dust), inhalation (paint)
Lead distributes throughout body in blood accumulates in bones
Depending on level of exposure, adversely affects nervous system, kidney function, immune system, reproductive and developmental systems, cardiovascular system
Affects the oxygen carrying capacity of the blood
Infants and young children especially sensitive to even low levels of lead
May contribute to behavioral problems, learning deficits
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Review Water Pollution materials on blackboard!
Submit Air Pollution current event assignment on blackboard by 2:29PM
Written assignment only,
No in-class discussion