SWBAT differentiate between different types of air pollution & the sources & mitigation for criteria pollutants.

Audit questions?

AIR POLLUTION – chemical or physical changes brought about by either natural processes or human activities resulting in air quality degradation.

OVER THE LAST 20 YEARS AIR QUALITY HAS IMPROVED IN DEVELOPED COUNTRIES & BECOME WORSE IN DEVELOPING COUNTRIES (10x’s higher in mega cities)

147 million metric tons of air pollution (not CO2 or dust) is released by the U.S./yr.

Natural sources of air pollution – volcanoes, dust storms, sea spray, viruses, bacteria, pollen, spores trees & vegetation (which emit VOC’s). Methane (2/3 ) from decaying vegetation & guts of termites & ruminant animals.

Anthropogenic sources alter & overload natural systems. Although most particulates come from natural causes, in some cities 90% come from human activities.

Primary pollutants – directly released from a source into the air in a harmful form.

Secondary pollutants – modified to a hazardous form after they enter the air (acid rain or smog) or are formed by chemical reactions as components of the air mix & interact. Example: Nox reacts to become acid rain.

Define criteria pollutants.:The Clean Air Act requires EPA to set National Ambient Air Quality Standards for six common air pollutants. These commonly found air pollutants (also known as "criteria pollutants").

SWBAT list the 6 criteria air pollutants and describe their source, health issues and mitigation by making a foldable.

Publications National Ambient Air Quality Standards (NAAQS)

Ambient Air – Air all around us.

The Clean Air Act, which was last amended in 1990, requires EPA to set National Ambient Air Quality Standards for pollutants considered harmful to public health and the environment. The Clean Air Act established two types of national air quality standards.

Primary standards set limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly.

Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings.

The EPA Office of Air Quality Planning and Standards (OAQPS) has set National Ambient Air Quality Standards for six principal pollutants, which are called "criteria" pollutants. Units of measure for the standards are parts per million (ppm) by volume, milligrams per cubic meter of air (mg/m3), and micrograms per cubic meter of air

(µg/m3).

Criteria or conventional pollutants contribute the largest volume of air-quality degradation & are considered the most serious of all air pollutants. 1970 Clean Air Act designated 6.

SWBAT describe the source, effects and remediation of the 6 criteria.

What do I need to do better?

Pollutant Symbol

Sources Human Health & Welfare Effects

Control Methods

Particulate MatterAirborne solid or liquid particles smaller than 10 microns in diameter or smaller than 2.5 microns

*Power plant boilerssteel mills*Chemical plants*Unpaved roads & parking lots•Wood-burning stoves & fireplaces•Automobiles & other.

PM

10

PM

2.5

Aggravates respiratory effects like asthma & emphysema.May cause lung and heart problems. May carry toxic material deep into the respiratory system. Impairs visibility

•Pollution control equipment (wet & dry scrubbers & cartridges) • Electrostatic precipitators.

Pollutant Symbol

Sources Human Health & Welfare Effects

Control Methods

Sulfur dioxide – a colorless nonflammable gas.

SO2 Power plant boilers, sulfuric acid plants, petroleum refineries, smelters, paper mills, & fuel combustion in diesel engines.

•Respiratory irritant.•Aggravates lung & heart problems.• + water = sulfuric acid.Sulfuric acid can damage marble, iron, steel & damage crops & vegetation, leach Al from soil.

•Crushing limestone & mixing it with coal. Dry or wet• Low sulfur coal.

Pollutant Symbol Sources Human Health & Welfare Effects

Control Methods

Carbon MonoxideOdorless , colorless gas.

CO Incomplete combustion of carbon-based fuels in motor vehicle & industrial boilers.

Reduces the ability of blood to deliver oxygen affecting the cardiovascular & nervous system. Impairs vision, causes dizziness, & can lead to unconsciousness or death.

Transportation planning, vehicle emissions testing, pollution equipment.

Pollutant Symbol Sources Human Health & Welfare Effects

Control Methods

OZONE(Smog) Colorless or bluish gas.

O3 Emissions of volatile organic compounds (VOC) & nitrogen oxides in the presence of sunlight.Fuel combustion in motor vehicles, gasoline storage & transport, solvents, pains & landfills.

Irritates mucous membranes, aggravates lung & heart problems. Damages rubber, some textiles & dyes. Damages plants. Reduces crop yields.

•Use of low-VOC solvents.• evaporative controls•vehicle emissions testing•pollution control equipment.

Pollutant Symbol Sources Human Health & Welfare Effects

Control Methods

Nitrogen DioxideA reddish-brown gas.

NO2 Fuel combustion in motor vehicles & industrial sources. High temperature burning combining nitrogen & oxygen in the air.

•Respirator irritant.• Aggravates lung & heart problems. •Precursor to ozone & acid rain. Causes brown discoloration of atmosphere.

•Staged burning; 1st high temp. w/ low oxygen which prevents most NOx from forming. •2nd Afterburner uses rich oxygen mix. 50% reduction.•Exhaust gas recirculation in cars, reduction of

combustion.•Catalytic converters reduce 90% of NOx.

Pollutant Symbol Sources Human Health & Welfare Effects

Control Methods

LEADA toxic heavy metal.

PbSmelters, lead-acid battery manufacturing, electric arc furnaces, incineration of garbage containing lead products, & use of leaded gasoline.

Toxic to the nervous system, organs, & most levels of body function.

Phase-out of leaded gasoline, & use of pollution control equipment in industrial plants.

The major parts of the Clean Air Act.

1963, 1970, 1990 & 1997

1963: A pool of money to be used by the states to set limits & regulate air pollution.

1970: Set specific standards for the criteria pollutants, (Also the EPA was established to not only set standards but also enforce them.)

1990: Added acid rain, HAP’s, ozone protection, marketing pollution rights, VOC’s

1997: Proposed lowering troposheric ozone from 0.12 ppm to 0.08 ppm. Lowering soot & dust from 10 microns to 2.5 microns & therefore requiring factories & powerplants to clean up emissions.

April 2, 2007 – In what may prove to be an historic turning point in the fight to reduce global warming, the U.S. Supreme Court today handed down a decision in a landmark environmental. In a 5-4 decision, the court ruled that carbon dioxide is a pollutant under the Clean Air Act and that the U.S. Environmental Protection Agency has the authority to regulate carbon dioxide emissions from automobiles and other vehicles.

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The major parts of the Clean Air Act.

1963, 1970, 1990 & 1997

1963: A pool of money to be used by the states to set limits & regulate air pollution.

1970: Set specific standards for the criteria pollutants, (Also the EPA was established to not only set standards but also enforce them.)

1990: Added acid rain, HAP’s, ozone protection, marketing pollution rights, VOC’s

1997: Proposed lowering troposheric ozone from 0.12 ppm to 0.08 ppm. Lowering soot & dust from 10 microns to 2.5 microns & therefore requiring factories & powerplants to clean up emissions.

Understanding the AQI https://www.youtube.com/watch?v=JVcFps_gWpk

The purpose of the AQI is to help you understand what local air quality means to your health. To make it easier to understand, the AQI is divided into six categories: Each category corresponds to a different level of health concern. The six levels of health concern and what they mean are:"Good" The AQI value for your community is between 0 and 50. Air quality is considered satisfactory, and air pollution poses little or no risk. = GREEN

"Moderate""Moderate" The AQI for your community is between The AQI for your community is between 51 and 10051 and 100. Air quality is acceptable; . Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number however, for some pollutants there may be a moderate health concern for a very small number of people. For example, people who are unusually sensitive to ozone may experience of people. For example, people who are unusually sensitive to ozone may experience respiratory symptoms. = YELLOWrespiratory symptoms. = YELLOW"Unhealthy for Sensitive Groups" When AQI values are between 101 and 150, members of sensitive groups may experience health effects. This means they are likely to be affected at lower levels than the general public. For example, people with lung disease are at greater risk from exposure to ozone, while people with either lung disease or heart disease are at greater risk from exposure to particle pollution. The general public is not likely to be affected when the AQI is in this range. = ORANGE

"Unhealthy" Everyone may begin to experience health effects when AQI values are between 151 and 200. Members of sensitive groups may experience more serious health effects. = RED"Very Unhealthy" AQI values between 201 and 300 trigger a health alert, meaning everyone may experience more serious health effects. = PURPLE

"Hazardous" AQI values over 300 trigger health warnings of emergency conditions. The entire population is more likely to be affected. = MAROON

Ozone - Good Up High, Bad Nearby!

Ozone is a gas composed of three atoms of oxygen. Ozone occurs both in the Earth's upper atmosphere and at ground level. Ozone can be good or bad, depending on where it is found:

•Good Ozone. Ozone occurs naturally in the Earth's upper atmosphere-6 to 30 miles above the Earth's surface-where it forms a protective layer that shields us from the sun's harmful ultraviolet rays. This beneficial ozone is gradually being destroyed by manmade chemicals. An area where the protective "ozone layer" has been significantly depleted-for example, over the North or South pole-is sometimes called "the ozone hole."

•Bad Ozone. In the Earth's lower atmosphere, near ground level, ozone is formed when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources react chemically in the presence of sunlight. Ozone at ground level is a harmful air pollutant.

Stratosphere Ozone Formation

1. O2 + UV -- 2O

2. O + O2 ----- O3

3. O3 + O -- 2O2

OR

3. O3 + UV -- O + O2

Video segment on stratospheric/good ozone.

2. Cl + O3 -- ClO + O2

3. ClO + O3 -- Cl + 2O2

1. CFC’s + sunlight Cl released

It takes CFC’s many years to ascend to the stratosphere & once they’re there they can last from 50 – 100 years.

One chlorine molecule has the ability to destroy 100,000 or more ozone molecules.http://www.atm.ch.cam.ac.uk/tour/part3.html

http://www.youtube.com/watch?v=XLY8m-dXOxo

Ozone NASA

GENERAL FACTS ON OZONEOzone is located mainly in the stratosphere 8 – 30 mi. (13 – 48 km) .

Ozone amounts are small; there are only a few molecules of zone in a million air molecules at most.Ozone is measured in Dobson Units. If you bring all ozone above a certain location to the ground & measured the height of the ozone, it would equal 300 Dobson Units (D.U.) which is equal to 3 millimeters in height. Less than 200 D.U.’s is considered a HOLE.

Ozone filters out biologically damaging UV light. Loss of ozone could cause:

1. Increase in skin cancer & cataracts.2. Decrease in crop yield.

3. Breakdown of the immune system.

4. Decrease in phytoplankton.

5. More solar radiation warming the troposphere & cooling the stratosphere.

http://www.youtube.com/watch?v=qUfVMogIdr8.

The Recipe For Ozone LossThe requirements for ozone loss are:* The polar winter leads to the formation of the polar vortex which isolates the air within it.* Cold temperatures form inside the vortex; cold enough for the formation of Polar Stratospheric Clouds (PSCs). As the vortex air is isolated, the cold temperatures and the PSCs persist.Once the PSCs form, heterogeneous reactions take place and convert the inactive chlorine and bromine reservoirs to more active forms of chlorine and bromine.* No ozone loss occurs until sunlight returns to the air inside the polar vortex and allows the production of active chlorine and initiates the catalytic ozone destruction cycles. Ozone loss is rapid. The ozone hole currently covers a geographic region a little bigger than Antarctica and extends nearly 10km in altitude in the lower stratosphere.

Total Ozone Mapping Spectrometer (TOMS) is an optical sensor to measure the albedo of the earth's atmosphere at six narrow spectral bands. The total ozone content is interrelated with changes of solar radiation in the near ultraviolet wavelengths so that the spatial distribution of the total ozone can be inferred by observing several near UV bands. In addition, the TOMS observation data can be used to make quantitative estimates of sulfur dioxide gases in the near UV band.

The following are international agreements dealing with the ozone depletion problem:

A. Montreal Protocol (1987) – 50% cut-back in CFC’s & Halons from 1986 levels.

B. Agreement in London (1990) – 100% phase-out by 2000 of CFCs & Halons.

C. Agreement in Copenhagen (1992) – U.S.A. & others – Acceleration of phase-out – 100% phase-out by 1996 of CFCs & Halons.

Formation of SMOG = Ozone

NO + VOC -------- NO2

NO2 + UV --------- NO + O (nitric oxide + atomic oxygen

O + O2 --------------- O3 (ozone)

NO2 + VOC ----------- PAN, etc. (peroxyacetyl nitrate)

NET RESULTS

NO + VOC + ONO + VOC + O22 + UV ----- + UV ----- O O33 + PAN, & other oxidants + PAN, & other oxidants

Video on catalytic converters.

INDUSTRIAL SMOG: Tends to be sulfur based and is also called INDUSTRIAL SMOG: Tends to be sulfur based and is also called grey-air smog.grey-air smog.

1.1. C + O2 ---- CO2 C + O2 ---- CO2

C + O2 ------ CO C + O2 ------ CO Carbon in coal or oil is burned in oxygen to Carbon in coal or oil is burned in oxygen to produce carbon dioxide & carbon monoxide gas.produce carbon dioxide & carbon monoxide gas.

2. C2. C Unburned carbon ends up as soot or particulate Unburned carbon ends up as soot or particulate matter.matter.

3. S + O2 ------ SO2 Sulfur in oil & coal reacts with oxygen gas to 3. S + O2 ------ SO2 Sulfur in oil & coal reacts with oxygen gas to produce sulfur dioxide.produce sulfur dioxide.

4. SO2 + O2 ----S03 Sulfur dioxide reacts with oxygen gas to 4. SO2 + O2 ----S03 Sulfur dioxide reacts with oxygen gas to produce sulfur trioxide.produce sulfur trioxide.

5. S03 + H20 ------ H2SO4 Sulfur trioxide reacts with water vapor in 5. S03 + H20 ------ H2SO4 Sulfur trioxide reacts with water vapor in the air to form sulfuric acid.the air to form sulfuric acid.

6. H2SO4 + NH3 ----- (NH4)2 SO4 Sulfuric acid reacts with 6. H2SO4 + NH3 ----- (NH4)2 SO4 Sulfuric acid reacts with atmospheric ammonia to form brown, solid ammonium sulfate.atmospheric ammonia to form brown, solid ammonium sulfate.

• Normally the warmest air is near the ground where it is heated during the day• Cold (dense) mountain air can slide down uplifting the warmer layer.•The colder upper layer keeps the warmer air from rising.•Pollutants are trapped in the cooler layer.

Urban heat island

A city is built mainly of concrete, asphalt, bricks and stones. As air temperature at a certain place depends to a large extent on the surface character, the temperature in a city is higher than in a non-urban area. The urban heat island is also caused by large number of habitants and anthropogenic heat emission.

Heat Island map of the New YorkThe hottest surfaces, overlaided in red! (35 K)Source: System for World Surveillance, Inc.

http://www.youtube.com/watch?v=GrwbVBKEqZg

Aesthetic degradation – any undesirable changes in the physical characteristics or chemistry of of the atmosphere.

Noise, odor, light pollution. Some are not harmful to health but degrade the quality of of our lives.

Unconventional Or Non-criteria Air Pollutants – considered especially toxic or hazardous & are regulated by the EPA. (HAP’s)

Asbestos, benzene, beryllium, mercury, polycyhlorinated biphenyls (PCB’s) & vinyl chloride.

Most of these materials have no natural source in the environment.

PCBs and Chemistry

PCBs or polychlorinated biphenyls are a group of chemicals consisting of 209 individual compounds. PCBs were widely used as a fire preventive and insulator in the manufacture of transformers and capacitors because of their ability to withstand exceptionally high temperatures.

PCBs were banned by the EPA in 1979, and are classified as a probable human carcinogen by numerous national and international health-protective organizations, such as the EPA, The Agency for Toxic Substances and Disease Registry (an arm of the U.S Public Health Service) and the World Health Organization. Research also links PCB exposure to developmental problems.

PCBs build up (bioaccumulate) in the environment, increasing in concentration as you move up the food chain.

Fugitive emissions – those that do not go through a smoke stack. Examples – dust from soil erosion, strip mining, rock crushing, & building construction & destruction. Leaks around valves & pipe joints from oil refineries & chemical plants.

https://www.youtube.com/watch?v=adzMcfHr1q8indoor air pollutionhttps://www.youtube.com/watch?v=LPvn9qhVFbMTemperature inversionhttps://www.youtube.com/watch?v=IKDpNTNm1CcDonora inversionhttps://www.youtube.com/watch?v=t-sXHl3l-rMurban heat islandhttps://www.youtube.com/watch?v=Nf8cuvl62Vcacid rainVideos to review