apes chapter 15

air pollution

air pollution

the introduction of chemicals, particulate matter, or microorganisms into the atmosphere at concentrations high enough to harm plants, animals, materials (buildings), or alter ecosystems

ground-level pollution

air pollution that occurs in the troposphere, the first 16 km (10 miles) above Earth's surface

sulfur dioxide (SO2)

corrosive gas that occurs anthropogenically when sulfur combines with oxygen during combustion of coal and oil; is a respiratory irritant which can harm plant tissues and form sulfuric acid in the atmosphere

nitrogen oxides (NOX: NO, NO2)

either colorless or reddish brown gases that occur anthropogenically with any type of combustion (fossil fuel, wood, biomass); are respiratory irritants and a precursor to ozone (photochemical smog), and can form nitric acid in the atmosphere

carbon monoxide (CO)

colorless gas that occurs anthropogenically with incomplete combustion of any kind; common in vehicle exhaust/combustion processes, leads to indoor air pollution and death at high concentrations

carbon dioxide (C02)

colorless gas that occurs anthropogenically with combusition of fossil fuels and clearing of land; alters climate and ecosystems by increasing greenhouse gas concentrations

particulate matter (PM: PM10, PM25)

solid or liquid particles suspended in air due to all types of combustion and dust mobilization; absorbs and scatters light; creates respiratory/lung/heart problems and contributes to haze and smog

haze

reduced visibility, mostly due to PM but also contributed to by ozone and photochemical oxidants

photochemical oxidants

air pollutants formed as a result of sunlight acting on compounds such as nitrogen oxides and sulfur dioxide

(tropospheric) ozone (03)

secondary pollutant fromed by combination of sunlight, water, oxygen, VOCs, and NOX; reduces lung/respiratory function, harmful to tissues, and damages construction materials

smog

mixture of oxidants and particulate matter, which occurs when photochemical oxidants increase the concentrations of particulate matter, scattering light and reducing visibility

photochemical smog

"Los Angeles-type smog" or "brown smog" dominated by oxidants such as ozone

sulfurous smog

"London-type smog" or "grey smog" dominated by sulfur dioxide and sulfate compounds

atmospheric brown cloud

combination of PM and ozone which is brownish or black due to the carbon particles and/or NO2 it attracts; observed in cities and regions such as Asia

lead (Pb)

trace metal found in gasoline, oil, coal, and old paint; impairs central nervous system and affects learning/intelligence (especially in small children)

mercury (Hg)

trace metal found in oil and especially coal, as well as the atmosphere and water due to mining/combustion; impairs central nervous system and bioaccumulates in the food chain due to poisoned fish

volatile organic compounds (VOCs)

organic compounds that become vapors at typical atmospheric termperatures; caused by evaporation of fuels, solvents, paints, and improper combustion of gasoline; usually hydrocarbons found in compounds that release a strong aroma, not a criteria air pollutant, but is a precursor to ozone/photochemical oxidant formation

primary pollutants

polluting compounds that come directly out of the smoke-stack, exhaust pipe, or natural emission source (ex., CO, CO2, SO2, NOX, most PM and VOCs)

secondary pollutants

primary pollutants that have undergone transformation in the presence of sunlight, water, oxygen, or other compounds (ex., O3, acid deposition [sulfate, nitrate])

National Ambient Air Quality Standards (NAAQS)

amendment of the EPA's Clean Air Act which specifies concentration limits for pollutants and requires localities to improve air qualities to meet these limits

smog formation

VOCs combine with nitrogen oxide to form photochemical oxidants, which reduces the amount of ozone that can break down later --> the photochemical oxidants (made of VOCS and NO) and the O3 together form smog

thermal inversion

a situation in which a relatively warm layer of air at mid-altitude covers a layer of cold, dense air below (as opposed to usual pattern of temperature decrease with altitude increase)

inversion layer

layer of warm air that traps emissions in a thermal inversion, creating severe pollution events and causing accumulation of pollutants below

acid deposition

deposition with a pH lower than 5.6; anthropogenically caused by SO2 and NOX reacting with oxygen and water to form nitric acid and sulfuric acid, which then breaks down into nitrate, sulfate, and hydrogen ions

fluidized bed combustion

granulated coal is burned in close proximity to calcium carbonate, which absorbs the sulfur dioxide and reduces SO2 emissions

baghouse filter

air pollution control device which removes particulate matter through a series of filter bags that physically filter out the particles

electrostatic precipitator

air pollution control device which negatively charges particles, which are then attracted to a positively charged plate, where they are held until removal and disposal

scrubber

air pollution control device where particles are "scrubbed" from the exhaust stream by water droplets; the water-particle "sludge" is collected and processed for disposal; also used to reduce SO2 emissions, and sometimes ionizes particles to improve efficiency

choroflourocarbons (CFCs)

family of organic compounds ideal for use in refrigeration/AC/aerosols/blowing agents, which are released

Montreal Protocol on Substances That Depelete the Ozone Layer (1987)

24 countries aggreed to reduce CFC production 50 percent by 2000, and resolved to work towards a solution to restore the ozone layer (addressed 96 ozone-depleting compounds)

asbestos

long, thin, fibrous silicate mineral with insulating properties; can cause respiratory diseases such as asbestosis and lung cancer to a) miners and b) those living with old/damaged fibers in the walls

carbon monoxide (as an indoor air pollutant)

binds with hemoglobin more efficiently than oxygen, interfering with oxygen transport and eventually leading to oxygen deprivation in the brain; caused by malfunctioning exhaust systems, colorless/odorless so builds up discreetly

radon

Radon-222 in granitic rocks/soils is seeped into buildings through cracks in foundation or found in contaminated drinking water, decays to Polonium-210; both the radon and the polonium attaches to particles and is inhaled, causing severe lung cancer

VOCs in home products

products may release VOCs such as formaldehyde, which leads to breathing difficulties/asthma and may even be a human carcinogen (building materials, furniture, glue/paints, cleaning products, plastics/fabrics, etc.)

sick building syndrome

a buildup of toxic compounds and pollutants in an airtight space; seen in newer buildings with good insulation and tight seals against air leaks (trade-off between energy conservation/indoor air pollution); caused by faulty ventilation, indoor chemical contamination, outdoor chemical contamination, and biological contamination

BioLite stove

physically separates solid fuel from gases and allows stove to burn only the gases; a small fan moves air through stove at rate that ensures complete combustion --> more efficient burn, less fuel use, less release of CO and PM

Chattanooga, Tennessee

city which had third worst particulate pollution in the country and high levels of respiratory disease due to manufacturing/industry; pollution caught in a bowl formed by surrounding mountains

1969: Air Pollution Control Ordinance;

controlled SOX emissions, permits for open burning, regulations on odors/dust/visible automobile emissions, capped fuel sulfur content, and monitored ordinances

1997: Early Action Compact;

improved ozone parts per billion in return for not being designated a nonattainment area; public/private sectors work together, people are educated to limit O3 production

Human Health, Welfare

The Clean Air Act's amendments control pollutants that a) harm the population including the children, elderly, and sensitive populations, and b) damages visibility, crops, vegetation, animals, ecosystems, and buildings

Black Triangle (German, Poland, Czech Republic)

combustion of high-sulfur content coal ("brown coal," lignite) which provides the fuel for power plants has caused this area to become one of the world's most polluted; respiratory illness and forest ecosystem damage has become apparent in the past 25 years