APES: Air Pollution and Stratospheric Ozone Depletion

Air pollution

chemicals, particulate matter, or microorganisms in the atmosphere at concentrations high enough to harm plants, animals, materials, or alter ecosystems

Particulate Matter (PM)

Solid or liquid particles suspended in air, AKA particulates or particles

Haze

reduced visibility from particulate matter.

Volatile Organic Compounds (VOC)

Hydrocarbons that become vapors at typical temperatures. Evaporation from fuels, solvents, paints, & improper combustion of fuels like gas. Ozone precursor

Primary pollutants

Pollutants direct from sources. CO, CO2, SO2, NOx, VOCs, CH4

Secondary Pollutants

pollutants from chemical reactions that occur when primary pollutants react with other primary pollutants or naturally occuring substances, such as water vapor, that they come in contact with

Inversion Layer

layer of warm air that traps emissions (pollutants) in a thermal inversion

thermal inversion

temperature inversion where warm air traps cold air and pollutants near the earth

Asbestos

a long, thin, fibrous silicate mineral with insulating properties, which can cause cancer when inhaled

Sick Building Syndrome

headaches, allergies, chronic fatigue and other symptoms caused by poorly vented buildings resulting in air containing pathogens or toxins--seen in newer buildings

Electrostatic Precipitator

device that removes suspended dust particles from a gas or exhaust by an intake of air, applying a high-voltage electrostatic charge, and collecting the particles on charged plates--cleaner air goes out, particles have to be removed by occasionally discharge

Sulfur Dioxide

SOx -Comes from combustion of fuels w/sulfur, including coal, oil, and gasoline. Respiratory irritant, can worsen asthma and other respiratory ailments. Can harm plant tissue. Converts to sulfuric acid in atmosphere, which is harmful to aquatic life and some vegetation.

Nitrogen Oxides

NOx- Comes from combustion in the atmosphere including fossil fuel combustion, wood and other biomass burning. Respiratory irritant, increases susceptibility to respiratory infection. Ozone precursor, leads to formation of photochemical smog. Converts to nitric acid in atmosphere, harmful to aquatic life and some plants. Contributes to over-fertilizing in terrestrial & aquatic systems.

Los Angeles-type smog

photochemical smog dominated by oxidants such as ozone (brown smog)

London-type smog

Smog dominated by sulfur dioxide & sulfate compounds (sulfurous smog, gray smog, industrial smog)

PM10 or PM2.5

Solid particles suspended in air from combustion of coal, oil, biofuels, and diesel. Agriculture, road construction, and other activities mobilize soil, soot, and dust. Can worsen respiratory and cardiovascular disease and reduce lung function. May lead to premature death. Reduces visibility and contributes to haze and smog.

Carbon Dioxide

CO2- Comes from -Incomplete combustion of any kind, malfunctioning exhaust systems, and poorly ventilated cooking fires. Bonds to hemoglobin thereby interfering with oxygen transport in the bloodstream. Causes headaches in humans at low concentrations, can cause death with prolonged exposure at high concentrations.

Ozone

O3. Blocks UV in the Stratosphere (good), but not good in the Troposphere. Secondary pollutant formed by combination of sunlight, water, oxygen, VOCs, and NOx. Reduces lung function & worsens respiratory symptoms. Harms plant surfaces. Damages things like rubber and plastic.

Lead

Pb. Gas additive, oil and gas, coal, old paint. Impairs central nervous system. At low concentrations, can have measurable effects on learning and ability to concentrate.

Mercury

Coal, oil, gold mining. Impairs central nervous system. Bioaccumulates in the food chain.

CO2

Combustion of fossil fuels and clearing of land. Affects climate and alters ecosystems by increasing green house gas concentrations.

Photochemical Oxidants

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

Smog

Mixture of oxidants and particulate matter.

Photochemical Smog

A brownish haze that is a mixture of ozone and other chemicals, formed when pollutants react with each other in the presence of sunlight

Sulfurous smog

Dominated by sulfur dioxide and sulfate compounds. London type or gray smog.

Clean Air Act

(RN), 1970 reaction to Rachel Carson in her 1962 in Silent Spring, It describes one of a number of pieces of legislation relating to the reduction of smog and air pollution in general. The legislation forced the country to enforce clean air standards to improve health and showed that American was moving towards certain environmentalist measures.

Ozone Formation

NO2 turns to NO + O transfers to O + O2 to form O3.

Photochemical Smog Formation

NO2 turns to NO + O transfers to O + O2 to form ozone. NO transfers to NO + VOCs to form Photochemical oxidants. Photochemical oxidants + Ozone = Photochemical smog.

Baghouse Filter

Dirty air enters, combustion exhaust stream moves through and dust particles are trapped in a series of filter bags, cleaner and filtered air moves out of unit, shaker mechanism activated periodically to dislodge trapped particles which can then be collected from below unit.

Indoor Pollutants

Furniture, Carpets, foam insulation, pressed wood produce VOCs

Tobacco Smoke: Toxic and carcinogenic

Old Paint: Lead

Floor & ceiling tiles, & pipe insulation: Asbestos

Rocks and soil beneath house: Radon

Household Products, pesticides, paints, cleaning fluids: VOCs & other compounds.

Fireplaces, wood stoves: Particulate Matter

Leaky or unvented gas or wood stoves and furnaces, running cars left running: CO.

CFCs

Chlorofluorocarbons. Man made chemicals used as coolants and propellants in aerosols. Potent greenhouse gases that also lead to depletion of the ozone layer. Phased out of use.

Scrubber

Dirty air enters, combustion exhaust stream moves up in shower of water mist, mist collects particles and brings to bottom of unit, dirty water moves to a sludge removal system, sludge is separated from water and disposed of, water moves back into scrubber for reuse, excess mist collects on screen and clean air leaves.

NAAQS

pollution standards for six priority pollutants set by the Environmental Protection Agency through the Clean Air Act

catalytic converter

a platinum coated device used on the exhaust of an automobile that oxidizes most of the VOCs and some of the CO that would otherwise be emitted in exhaust, converting them to CO2.

Radon-222

radioactive gas from decay of uranium in rocks, can lead to lung cancer

cap and trade

Market-based system of pollution control whereby individual businesses can buy and sell emission credits even while the total level of industry pollution is capped at some level.

Fluidized bed combustion

combustion process reduces the NOx and SOx emissions from coal

involves mixing crushed coal and limestone. Most of the SO2 in the coal is neutralized by the limestone. The heat generated is used to convert water to steam

Ozone layer hole

increases skin cancer and changes climate/plant growth