Monitoring Air Quality Dr. Angela C. Morrow, University of Northern Colorado

Copyright © College Entrance Examination Board. All rights reserved.

Abstract Due to air quality laws requiring the reduction of air pollutants and development of such products as air scrubbers, the amount of pollution in our air is less than has been in several decades. However, most of us do not live in an area where the air quality would be considered "very clean and pure". In fact, we live in areas with varying air quality. During this laboratory exercise, you will design and build an air scrubber and assess air quality in a designated area.

Objectives: 1. Correctly describe and discuss several air pollutants and methods for detecting them. 2. Correctly describe the chemical reactions behind how several monitoring systems function.

Introduction Degrading air quality due to motor vehicles convinced the California legislature to enact the first air pollution laws in the U.S. in 1947. The results of this law were to establish air pollution control districts and in 1960, to require of air pollution control devices on cars. In 1970, the U.S. government passed the Clean Air Act establishing the national ambient air quality standards (NAAQSs). The act set standards for maximum allowable concentrations of pollutant for a distance from a source in a time. This act was helpful but not perfect, and it resulted in some silly solutions such as simply building a taller smoke stack. Of course, building a taller smoke stack isn't a solution and amendments to the Clean Air Act have addressed some of these problems by dealing with annual emissions of pollutants. The good news is that there has been a major reduction in many pollutants; however, population increases and increases in the number of cars have prevented a significant reduction in some pollutants such as carbon and nitrogen oxide.

One of the most important components of industrial air pollution control is scrubbers for the removal of sulfur. As any protein or protein-derived product burns, sulfur is emitted. Scrubbers remove the sulfur from the emissions by spraying a solution of calcium oxide or calcium carbonate into the stream of gas coming from the combustion chamber. The reaction between the sulfur and the calcium compound produces calcium sulfite or calcium sulfate that commonly is known as gypsum. Gypsum is used in the production cement, plaster and wall board. In fact, in Japan where there are no deposits of gypsum, it is collected from scrubber units and used in these products.

The type of pollutants in the air is numerous and varies in chemical composition; therefore, our definition of air pollution must reflect this multiplicity. Additionally, we must test for air pollutants in a variety of ways to come to a more realistic picture of air quality.

Materials:

Graph Paper Clipboard/pencil Measuring Tape Lichen KeyGoggles Apron Duct Tape Dissecting Probe Filter paper (10 cm or larger) Cornstarch Hole Punch Plastic bagsSodium thiosulfate Medium Paintbrush Fishing Line Distilled waterPlastic bags Eco badges Potassium iodide 250 ml BeakerStirring Rod Hot Plate Scale ScupulaGlue Scissors Weigh Dish Index CardsRoll of Pet Hair Removal Tape Cellophane Tape Newspaper Lab Gloves

Key of common fungi and bacteria Microscope slides and cover slips Bacterial/Fungi media - optional

Procedure Part One Your assignment is to sample your designated grid for particulate, ozone, and general air quality.Lichen1. Identify a tree closest to the center of your grid and measure its diameter at chest height. 2. Map the lichens from the chest-high mark to the base of the tree identifying the type (crustose, foliose, fruticose) of lichen and indicating the size of the lichen patch. 3. Design and set-up a grid of 20 squares (each lab group is responsible for two non-adjacent squares) covering a portion of the wooded and cleared (developed) area of campus. Design the grid squares to be a uniform size, dimension, and design. (NOTE: Generally, 5 x 5 meters square is a reasonable size for each grid block.)4. Use a map of campus to identify and draw your squares on the map in their relative locations.5. On a separate sheet of paper, describe the biotic (living) and abiotic (non-living) environment of your squares. Also, note human disruption or development associated with your squares. Estimate the number of plant species occupying each square.6. Using number symbols for each type of lichen (i.e. 1 for Type 1, 2 for Type 2, 3 for Type 3), note the locations of lichen colonies within each of your squares. Score the air quality of your square using the following formula:

Type 1 = 1 pt. per colonyType 2 = 3 pts. per colonyType 3 = 5 pts. per colonyNo Type = 0 pts. per colony

7. You also need to use the modified Hawksworth and Rose Index below determine the relative air quality.

No lichens present (very poor) Crustose lichens only (poor) Leafy and crustose lichens (moderate to good air) Foliose, leafy and crustose lichens present (good air) Foliose lichen (Usnea articulate) (string of sausages) (very clean air)

8. Photocopy your data map and qualitative data and tape copies to the wipe board with your group names written above. Pool/share your data with the class. Record each of the other squares on your map and collect the plants and qualitative data from each of the lab groups.

  Type 1 - Crustose Type 2 - Foliose Type 3 - Fruticose

Crustose: crust-like, adhering tightly to the substrate by their entire lower surface. Some endolithic lichens are embedded in their rock substrate. Foliose: leaf-like with a distinct upper and lower surface, attached to their substrate only by small root-like structures, rhizines.Fruticose: shrub-like, pendulous strands or hollow stalks called podetia, usually attached to the substrate at the base or holdfast; small tree or bush-like appearance

Ozone Eco BadgeWear your Eco Badge indicator per manufacturer's instructions while you are working in your grid. Read directions for exposure and reading results. Record your results.

Indicator Paper1. Prepare a set (suggested 5-10 papers) of ozone indicator papers in following manner:a. Mix 2 grams of potassium iodide, 10 grams of cornstarch, and 100 mL of water. Heat to form a paste. Wear gloves while making this paste and applying it to the filter paper. b. Trying not to touch the surface of the filter paper, tape a piece of duct tape over card and punch a hole in the paper to allow for hanging. Then brush a coat of the indicator paste on the surface of the filter paper. Allow to dry. Best results are by microwaving for approximately one minute or bake in oven at 300 degrees until dry.2. Using fishing line, hang set of detectors at random points in your grid and allow to hang for 24 hours.3. Map the location of your indicators within your grid.4. Remove fish line and check for change in coloring. Indicator turns blue in presences of ozone. A darker color indicates higher ozone level. Use color chart on page #12.5. Record your results. Compare the results of your Eco Badge with your indicator papers.

Particulates1. Prepare particulate collectors by gluing a strip of cellophane tape and a strip of pet hair removal paper on a blue index card. Holes may be punched, and hangers added (as in previous experiment). 2. Place cards in random areas of your grid and map the location of your collectors. 3. After a predetermined time remove your cards and record their appearance. 4. Prepare one or more wet mounts using scrapings obtained from collection cards. 5. Examine your wet mounts under the microscope and record your findings.

Further StudyParticulates may be scraped onto plates with nutrient media. After incubating for 24 hrs. check for bacterial or fungal growth.

Lab Tip As several oxidizing agents (i.e. NO2) can cause bluing, 1-gram sodium thiosulfate may be added to paste to prevent premature bluing. O2 will not cause bluing.

Data /Observations

Part One 1. Designate a method to indicate the type of lichen found on your sample tree and prepare a map of the lichen distribution. 2. Match the color of your Eco Badge with the ozone level and record the results. 3. Draw a map of the hanging ozone detectors and indicate the color results. Be sure you indicate on your map the outlying areas which might influence the level of ozone i.e. streets, parks, loading zone etc. 4. Draw a map of the particulate collectors and indicate the results from the collectors. Draw illustrations of the particulates that you observed under the microscope.

Analysis

Part One: Based on the data you collected from your grid, what is your conclusion of the air quality of the area? Indicate features in your grid or surrounding your grid that would affect the air quality. How well did the data you collected from the different types of samples agree? For example, did the levels of ozone indicated on your Eco Badge agree with the data from your hanging detectors?Your report on this laboratory should include the following:

a. Map of lichen distribution and assessment of air quality b. Mounted Eco Badge strip and determined results c. Map of ozone detectors and results - Answer 7 questions on page #12.d. Map of particulate collectors and results - Answer 4 questions on page #8.e. Illustrations of particulates from microscope observations f. Analysis of air quality g. Problems (equipment, weather etc.) h. Other

Airborne Particulate LabAirborne particulates are among the unhealthiest components of air pollution to humans. Very small particulates can lodge deep inside lung tissue where they can stay throughout the life of a person. The sources of particulates can be natural as well as anthropogenic. Airborne dust, pollen, soil, or particles from the smoke and exhaust of automobiles, factories, and power plants all contribute to the total amount of particulates in the air.

Every member of the class will measure the particulate concentration inside and outside their home, and then contribute their individual data to the efforts of the entire class to uncover trends in the distribution patterns of particulates in the community.

Fast Facts (From →https://www.epa.gov/environmental-topics/air-topics) Particles that are less than 2.5 micrometers in diameter are known as "fine" particles; those larger than 2.5

micrometers, but less than 10 micrometers, are known as "coarse" particles. Fine particles are easily inhaled deep into the lungs where they may accumulate, react, be cleared or

absorbed. Scientific studies have linked particle pollution, especially fine particles, with a series of significant health

problems, including: increased respiratory symptoms, such as irritation of the airways, coughing, or difficulty

breathing, for example; decreased lung function;

aggravated asthma; development of chronic bronchitis; irregular heartbeat; nonfatal heart attacks; and premature death in people with heart or lung disease.

Plant pollen

Particle pollution can cause coughing, wheezing, and decreased lung function even in otherwise healthy children and adults.

Studies estimate that thousands of elderly people die prematurelyeach year from exposure to fine particles.

The average adult breathes 3,000 gallons of air per day. Insect body parts

According to the American Academy of Pediatrics, children and infants are among the most susceptible to many air pollutants. Children have increased exposure compared with adults because of higher minute ventilation and higher levels of physical activity.

Fine particles can remain suspended in the air and travel long distances. For example, a puff of exhaust from a diesel truck in Los Angeles can end up over the Grand Canyon.

Some of the pollutants which form haze have also been linked to serious health problems and environmental damage.

Particle pollution settles on soil and water and harms the environment by changing the nutrient and chemical balance.

Particle pollution, unlike ozone, can occur year-round. People can reduce their exposure to air pollution by checking their daily air quality forecast and adjusting

strenuous outdoor activities when an unhealthy AQI is forecast.

Particulate Matter Air PollutionWhat is Particulate Matter? Particulate matter -- particulates or PM for short -- refers to the many types and sizes of particles suspended in the air we breathe each day. Particulates include products of combustion, such as soot or ashes, wind-blown dust, and minute droplets of liquids known as aerosols. PM can range in size from visible pieces of sand and dirt to microscopic particles so small that 500,000 of them could fit on the period at the end of this sentence.

Why should you be concerned about PM? Particulate matter not only impairs visibility, it also poses a serious health threat to citizens. Our respiratory systems are equipped to filter out larger particles. However, the lungs are vulnerable to particles less than 10 microns in diameter (PM10), which can slip past the respiratory system's natural defenses. Very tiny particles (PM2.5) can penetrate deeply into the lungs and do the most harm.

The particulates we breathe enter the lungs and pass through progressively smaller airways until they reach the alveoli, tiny air sacs where oxygen enters the blood stream. Particulates that get trapped in these most sensitive tissues interfere with oxygen uptake. Toxic and cancer-causing compounds can "hitchhike" into the lung on these particulates and be directly absorbed into the lungs.

What are the health effects of PM air pollution? PM air pollution can cause coughing, wheezing, and overall decreased lung function in otherwise healthy children and adults. Particulate pollution can trigger asthma attacks and respiratory illness in the more sensitive subgroups of the population, such as the elderly and those with heart and lung disease. Children are more susceptible to particulates because they have smaller lungs and less mature immune systems. In the past 10 years, more than two

dozen health studies have linked high concentrations of particulate air pollution with an increase in emergency room visits, hospital admissions, and even premature death.

What causes PM air pollution? PM is introduced to the air through both natural and human causes. The primary sources of PM in California, excluding agricultural dust, are motor vehicles; diesel trucks and buses; residential wood stoves and fireplaces; industrial emissions; agricultural, slash and yard waste burning; and even exhaust from lawn mowers and boats. PM concentrations tend to be especially high in area with greater population density, nearby industries or agriculture, or where local topography or weather conditions contribute to air stagnation. Here are a couple of quick facts about sources of particulate matter:

During wintertime air inversions, wood stoves and fireplaces release more hazardous particles. Diesel trucks and buses are major producers of particulate matter and should be replaced with natural

gas-, methanol-, or electric-powered vehicles. As our population increases, our vehicle miles traveled increases at a much higher rate, which means

more cars on the road and more air pollution from motor vehicle exhaust. Industrial emissions are a major source of air pollution. The best control technologies should be

encouraged to protect human health and the environment.

What is being done to control PM air pollution? Our nation's Clean Air Act of 1970, in combination with important amendments adopted in 1977 and 1990, requires that the United States Environmental Protection Agency (EPA) identify and set standards for air pollutants. These National Ambient Air Quality Standards (NAAQS) must be strict enough to protect the health of even the most sensitive members of the population. PM10 is currently one of six "criteria" pollutants identified by the EPA. Here in California, the Department of Ecology and local air pollution control agencies cooperate with the EPA to implement laws designed to reduce PM levels.

National Ambient Air Quality Standards (NAAQS) 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.

National Ambient Air Quality Standards

Particulate Matter (PM10)

50 μg/m3 Annual2 (Arith. Mean) Same as Primary150 ug/m3 24-hour1

Particulate Matter (PM2.5)

15.0 μg/m3 Annual3 (Arith. Mean) Same as Primary65 ug/m3 24-hour4

A New PM Standard Though our air quality has improved since adoption of these laws, our visibility has worsened. There is also mounting evidence that the PM10 standards may not be strict enough to protect lung health. A 1996 analysis by the Natural Resources Defense Council (NRDC) estimates that PM levels far below current air pollution limits contribute to over 1,000 premature deaths each year in Washington state. Experts suggest that changing the PM standard to contain limits on fine particles (those 2.5 microns or less in diameter) would better protect lung health. A PM2.5 standard might mean tougher restrictions on diesel

trucks and buses, wood stove and fireplace usage, outdoor burning, and industrial sources. It will also mean that citizens will breathe easier and spend less on health care to treat PM-induced illnesses.

POLLUTANT SOURCES HEALTH EFFECTS STANDARDParticulate Matter (PM) Wood burning, motor

vehicles, industry, outdoor burning, windblown dust,

construction, mining, unpaved roads, diesel

Eye and nose irritation, airway irritation,

cough, decreased lung function, increased respiratory illness,

premature mortality

PM10 150 μg/m3 (24-hour average) PM10 50 μg/m3 (annual

average)

What are bioaerosols?

A healthy indoor environment is important to you and your family. This includes keeping the air free of biological contaminants, which can cause health problems. Scientists call these airborne contaminants bioaerosols.

Bioaerosols are extremely small living organisms or fragments of living things suspended in the air. Dust mites, molds, fungi, spores, pollen, bacteria, viruses, amoebas, fragments of plant materials, and human and pet dander (skin which has been shed) are some examples. They cannot be seen without a magnifying glass or microscope.

Can bioaerosols cause health problems? They can cause severe health problems. Some, like viruses and bacteria, cause infections (like a cold or pneumonia). Others cause allergies. Both allergic responses and infections may be serious or even fatal. An allergic reaction occurs when a substance provokes formation of antibodies in a susceptible person. We call substances which will cause an allergic reaction in some people antigens or allergens. Bioaerosols may cause allergic reactions on the skin or in the respiratory tract. Rashes, hay fever, asthma (tightness in the chest, difficulty in breathing), and runny noses are common allergic reactions. A few people develop a severe allergic reaction in the lung, which can destroy lung tissue. This is called hypersensitivity pneumonitis. It is not an infection, but repeated episodes can lead to infections of the lung, such as bacterial pneumonia. Hypersensitivity pneumonitis can be triggered by exposure to very small amounts of the allergen, once a person is sensitive to it. Symptoms can range from tightness in the chest, cough, and difficulty in breathing, to low-grade fever, muscle aches, and headaches.

Dander from animal skin

What are sources of bioaerosols in the home? Molds, mildews, bacteria, and dust mites like the same conditions that we do--warmth and moderate to high humidity. They need little more than a constant moisture supply for survival. You may find bacteria, molds, and mildews in air conditioning equipment, humidifier reservoirs, dehumidifier drip pans, shower

heads, toilets, and ice machines. Water damaged carpets, ceiling panels, walls, and paneling are prime sites for new growth if they can stay damp. When molds, mildew, dust mites, and bacteria are disrupted or release their spores into the air, this results in bioaerosol formation. Molds and mildews develop from spores, which are in the air all around you. As soon as spores settle in with the right conditions for growth, they establish colonies, which are often visible to the naked eye. These colonies are a source of more spores, can cause unsightly stains, and may release low levels of toxic chemicals called mycotoxins into the air.

Humidifiers are such a common source of bioaerosols that cause health problems that doctors now use the term humidifier fever. Protozoa, amoebas, and strains of bacteria have been found in humidifiers, and these are readily released into the air with the moisture produced by humidifiers. These have been linked to allergic responses in sensitive people. Mold and mildew may be found in the ductwork of your heating or cooling systems. If there are leaks in the ductwork, or places where moisture and outside air get into the system, mold and mildew can grow. Sometimes they are found in the coils of an air conditioner or in the connection between the unit and the ductwork. Moisture problems are worse where ductwork insulation is on the inside as opposed to the outside of the duct. The insulation's porous surface collects dust and moisture. Mold and mildew may also grow on dirty furnace and air conditioning filters.

Plumbing leaks and dampness in attics, basements, and crawl spaces can increase humidity inside your home and promote the growth of agents that will be released as bioaerosols. Bathrooms without outside-vented exhaust fans, combustion appliances like kerosene space heaters, drying laundry indoors, and venting clothes dryers to attics or crawl spaces can also increase the humidity levels in your home. Dust mites and their waste products are the most common allergens in indoor air. Dust mites eat human and pet skin (dander) as it is shed. It has been estimated that we shed about seven million cells per minute! Dust mites live in rugs and carpets, sheets, mattresses and pillows, and upholstered furniture. Ten to 15 percent of people are allergic to dust mites.

Conclusion Questions - From Reading

1. What is the difference between a “fine” vs. “course” particulate pollutant? 2. List three health effects caused by “fine” particulates? 3. What are the major anthropogenic causes of particulate pollution? 4. What are some of the benefits and negative aspects to tighter particulate pollution controls?

Photo 1: Graphite (x25). Opaque, black, sharply angular Photo 2: Coal (x16). Black, opaque, sharply angular.

flakes, irregularly shaped (sometimes hexagonal).

Photo 3: Coke (x25). Opaque, black, sharply angular with Photo 4: Oil Soot (x40). Dark, translucent cenospheres.

rough highly reflective surface.

Photo 5: Wood Fibres (x16). Colorless to pale, yellow fibres Photo 6: Silica Sand (x16). Colorless, transparent crystals.

Photo 7: Fly ash (x40). Transparent, brown, milky spheres. Photo 8: Limestone Debris (x10). White to greyish limestone debris.

Photo 9: Insect Parts (x16). Legs, fragments of wings, hair, Photo 10: Magnetic Iron Spheres (x40). Shiny spheres. chitinous body, etc.

Photo 11: Wood Char (x16). Carbonized, opaque, black, Photo 12: Mineral Wool Fibres (x10). Transparent, colorless to brown, shiny on the surface. isotopic, smooth cylinders straight or gently curved.

SCHOENBEIN COLOR SCALE

0 1 2 3 4 5 6 7 8 9 10

SCHOENBEIN NUMBER

0-3 Little or no change

4-6 Lavender Hue

7-10 Blue or Purple Hue

RELATIVE HUMIDITY CHART

POST LAB QUESTIONS: Use the web site listed at beginning to see color charts of ozone concentrations present.

1. Determine the ozone concentration for Schoenbein paper with a Schoenbein Number of 2 at a relative humidity of 23%, 48%, and 81%.2. Determine the ozone concentration for Schoenbein paper with a Schoenbein Number of 5 at a relative humidity of 18%, 53%, and 77%.3. If the ozone concentration in two areas was 100 ppb, determine the Schoenbein Number if the relative humidity was 28%, 40%, and 72%.4. Describe the changes you observed in the Schoenbein paper you used. List your ozone concentration from your graph.5. Compare your data with data obtained from a local weather source for ozone levels. Based on this comparison, discuss the reliability of using Schoenbein paper to measure tropospheric ozone. How does your value compare with published data?6. List the pollutant rating for the following pollutants Ozone (O3), Sulfur dioxide (SO2), and Carbon monoxide (CO). Click on the link below and type in Prince Frederick MD.

http://www.homefacts.com/airquality.html7. Estimate the approximate UV Index at the test site during the lab. Explain how the UV Index is related to the concentration of ozone present in air. (Read the information on this link before answering https://www.epa.gov/sunsafety/uv-index-scale-1 Consult this link as well to answer some of the questions in this lab. http://www.airnow.gov/index.cfm?action=pubs.aqiguideozone