Materials Included In Kit

Additional Materials Required

Safety Precautions

Although this activity is considered nonhazardous, follow all normal laboratory procedures.

Disposal

Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures, and review all federal, state and local regulations that may apply, before proceeding. All materials may be placed in the trash according to Flinn Suggested Disposal Method 26a.

Teacher Tips

• Students may wish to perform the tests in an outdoor environment. Plan class time accordingly.
• Encourage students to place their slides in a variety of locations. Allow students to take their slides out of the classroom to sample the total particulates in or around their homes. Compile class data for the different locations and compare individual results.
• Enough slides and labels are provided in the kit for 144 tests.
• Stereoscopes, if available, may also be used to examine the samples.

Further Extensions

• Have students write reports on certain pollutants, and their sources and effects. Encourage students to use the Internet and local libraries to explore the wide range of air pollution that exists.
• Contact local manufacturing facilities and see if you could take a tour of their plants. Discuss the steps that the company takes to reduce the amount of pollution coming from their facility.
• Visit the United States Environmental Protection Agency’s (EPA) website at www.epa.gov for further information on air pollution.

Sample Data

Answers to Questions

1. Did your test area have low or high particle pollution? Give examples of possible sources of particle pollution in your test area.

   My test area has a low amount of particle pollution. Particles may have come from clothes, natural fibers, etc. from an open window or ventilation ducts.

2. Compare your results with your classmates. Which location had the highest number of particulates?

   Answers will vary.

3. Which location had the largest particulates? the smallest?

   Answers will vary.

4. Which location had the most variable types of particulates?

   Answers will vary.

References

Cunningham, W. P.; Woodworth, S. B. Environmental Science: A Global Concern; William C. Brown: Dubuque, IA, 1997; pp 385–390.

Introduction

How clean is the air that we breathe? How does the air look, taste, feel and smell in your local community? In this laboratory activity, an airborne particulate test will be performed to help answer these questions.

Concepts

• Air quality
• Particulates
• Air pollution

Background

The major components of pollution-free, dry air are nitrogen (78%), oxygen (20.95%), argon (0.934%) and carbon dioxide (0.0314%). Air also contains trace quantities of neon, ammonia, helium, methane and krypton. If other substances are added to the atmosphere, an imbalance occurs that leads to the degradation of the air. The air in your area is probably polluted to some extent. Air pollution is probably the most widespread and most noticeable type of pollution that affects our lives. Each year in the United States, 147 million metric tons of pollutants are released into the atmosphere as a result of human activity. Worldwide, nearly 2 billion tons of air pollutants are released into the atmosphere.

In this activity, the relative amount of particulate material in the local air will be measured. Particulate materials, also known as aerosols, are defined as any group of liquid droplets or solid materials suspended in air. Particulate materials include substances such as dust, lint, smoke, pollen, ash, as well as may other suspended materials. Particulate materials are often the most visible and noticeable type of air pollution and can be harmful to many organisms. Common respiratory diseases, such as asthma, chronic bronchitis, emphysema, and lung cancer, have been directly related to various types of airborne particulates. Natural sources of particulate material in air worldwide account for more than ten times the pollution than human created sources. However, in many cities, more than 90% of suspended particulate matter is due to human intervention.

Materials

Safety Precautions

Although this activity is considered nonhazardous, follow all normal laboratory procedures.

Procedure

1. Place a label, sticky-side up, on a microscope slide. This may be done by curling two of the outside edges of the label down so the label will stick to the slide (see Figure 1).
   {13916_Procedure_Figure_1}
2. Choose a location, inside or outside, to place the slide. Be sure to choose a different location than other classmates (i.e., inside a classroom by a window, in a tree, near the corner of the school building). Choose an area that is exposed to the air, elevated off the ground and, if possible, sheltered from rain. Be sure to describe where the slide was placed. Record the placement of the slide in the data table.
3. Leave the slide in the same location for seven days.
4. At the end of the seven days, collect each sample.
5. Using a magnifying glass, look at the particulates on the label and record observations in the Airborne Particulates Worksheet. Measure and draw two 1-cm squares on the label. Count or estimate how many particles are in each of the squares (look for white as well as dark specks) and record these values in the data table. Average the two counts for overall particles per square centimeter. Record this value in the data table.
6. Total particle counts between 100 to 500 per square centimeter indicate slight particle pollution. Values over 500 particles per square centimeter relate to high particle air pollution.
7. Record your count number results on a class record chart as directed by your instructor.

Student Worksheet PDF

13916_Student1.pdf