Air pollution and control

Smoking is the most important air pollution in the U.S.

400,000 die annually from diseases related to smoking. This is 20% of all mortality. Associated costs are estimated at $100 billion annually.

1990 amendments to clean air act

Acid rain Urban air pollution Toxic emissions Ozone depletion

stratospheric ozone

Circumpolar vortex isolates Antarctic air and allows stratospheric temperatures to drop and create ice crystals at high altitudes. --absorb ozone and chlorine molecules

indoor air pollution

EPA found indoor concentrations of toxic air pollutants are often higher than outdoor

One of the principal ways lakes suffer from acid deposition is that:

Fish eggs die & fish populations fall

acid rain controls

Fuel switching Coal washing Coal mixing with alkaline treated municipal sludge Scrubbers Fluidized bed combustion Reduced consumption of electricity

cause of acid rain

H2SO4 and HNO3 from industrial and automobile emissions

Clean Air Act 1970

Identified critical pollutants. Established ambient air quality standards.

acid rain

It is caused by sulfur dioxide & nitrogen oxides being released into the environment Coal-burning power plants & Motor vehicles

effects of acid rain

Leach nutrients in the ground Kill nitrogen-fixing microorganisms that nourish plants Kill fish Release toxic metals

ozone

O3 layer in the stratosphere shields the biosphere by absorbing incoming uv radiation. (in the troposphere it is a pollutant)

Volatile Organic Compounds (VOCs)

Organic chemicals Generally oxidized to CO and CO2 Plants are largest source. 400 million tones of methane produced by natural wetlands and rice paddies

bronchitis

Persistent inflammation of airways in the lung that causes mucus build-up and muscle spasms constricting airways

Hazardous Air Pollutants (HAP)

Require special reporting and management as they remain in ecosystems for a long period of time, and tend to accumulate in animal tissues. Include carcinogens, neurotoxins, endocrine disrupters

stratospheric ozone depletion

Stratospheric ozone levels are rapidly droping over south pole. At ground-level, ozone is a pollutant, but in the stratosphere it screens UV radiation

criteria pollutants

Sulfur Dioxide Nitrogen Oxides Carbon Monoxide Ozone Lead Particulates

criteria pollutants

The 1970 amendments to the Clean Air Act required EPA to set National Ambient Air Quality Standards for certain pollutants known to be hazardous to human health. EPA has identified six criteria pollutants: sulfur dioxide, carbon monoxide, lead, nitrogen oxides, ozone, and particulate matter.

particulate matter

aerosols-( solid particles or liquid droplets suspended in the atm) when smaller that 2.5 micrometers they can enter the lungs and cause damage

cap and trade programs

begun in 1990,set maximum amounts for pollutants, but let facilities facing costly cleanups pay others with lower costs to reduce emissions on their behalf

Fluidized bed combustion

burn coal with sand & lime with air - very costly-would require tearing down existing plants - good solution for new plants.

secondary pollutants

converted to a hazardous form after entering the air and mixing with other air components

fugitive emissions

do not go through smokestack (Dust from strip mining, rock crushing, building construction/destruction)

Electrostatic Precipitators

fly ash particles pick up electrostatic charge as they pass between large electrodes in waste stream, and accumulate on collecting plate

emphysema

irreversible chronic obstructive lung disease in which airways become permanently constricted and alveoli are damaged or destroyed.

sulfur dioxide

is a corrosive gas which reacts with water vapor in the air to cause acid rain

temperature inversions

occur when a stable layer of warm air lies above cooler air, reversing the normal temperature decline with increasing height, and prevents convection currents from dispersing pollutants.

acid precipiation

pH 5.5 or less

Montreal Protocol (1987)

phased out use of CFCs. HCFCs were substituted, which release less chlorine.

Aesthetic Degradation

reduce quality of life by increasing stress

Chlorofluorocarbons (CFCs)

release chlorine and fluorine in the stratosphere, which deplete ozone layer. CFCs banned in developed countries but still used elsewhere in propellants and refrigerators

primary pollutants

released directly from the source

coal washing

removing sulfur - costly economically & environmentally

Toxic Release Inventory

requires manufacturers to report on toxin release and waste management. Most HAP are decreasing but mercury and dioxins (from plastics) are increasing.

synergistic effects

the injury caused by the combination is more than the sum of the individual exposures.

grasshopper transport

volatile compounds evaporate from warm areas; travel to poles where they condense and precipitate. Contaminants bioaccumulate in food webs. Whales, polar bears, sharks have dangerously high levels of contaminants (such as HAP).

Clean air act 1963

was the first national legislation in the United States aimed at air pollution control. revised in 1970