You're outside in the yard with your family or at the local park. Maybe you're hanging out with your friends at the mall or skate park. A typical beautiful day; having fun, keeping busy, staying healthy. But wait! What are you breathing in as you go about your typical day? Everyday you are breathing the air around you, wherever you happen to be. You can't see it but you can feel it as you breath and sometimes you can smell it. But what is it? Does it matter? Can air quality affect your health? Yes! The air your breath does matter. Even though you can't see it and sometimes can't smell it, the air around you can contain toxic particles that can make you sick. A simple experiment will let you know exactly what you're breathing and what it can mean to your health.

Our lungs absorb oxygen from the air and pass it into our blood stream so it can be transported throughout our bodies. Oxygen is important for our whole body as it provides energy we need to survive.

Did you know that in industrial areas you are more likely to develop asthma? It's also true that smokers are more likely to suffer from lung disease. Years of breathing particles of tar and smoke found in cigarettes and cigars can cause the lung tissue to develop cancer which can lead to premature death.

How clean is the air where you live? What about around your school, where you play at the park, or where you work? Is the air at a park cleaner than air near a busy intersection? You can do a simple earth science experiment with Vaseline to find out the answers to these questions.

Here are the procedures for a simple project you can do to determine how good or bad the air is where you live, go to school and play. This would also make a great experiment for your school science fair! You will need some Vaseline, string, a milk carton, and a magnifying glass. These are your first steps:

- Clean and dry the carton thoroughly before use.

- Cut the carton into four flat pieces by cutting along the side seams of the carton.

- Cut each side into 3 square pieces, each piece will be approximately 3 inches long and 3 inches wide. You will have a total of 12 squares when you are done.

- Punch a hole in one corner of each square.

- Tie a piece of string through the hole to make a loop for hanging the square up, on a tree branch for example.

Next, make a data sheet to record where you place your squares, and what data you will collect from them:

- Using a black marker, draw a box about 1 inch square in the middle of the inside of each of the carton pieces.

- Use three squares for each location, Write the name of the location on the bottom of each square.

Then, pick three areas where you spend most of your time. In your backyard, in the school yard, where you shop, where you play, your local park. Try to pick three days without rain or place the collection squares in sheltered spots:

- Hang up three of your collection squares from a tree branch, sign post, light post, or any other safe landmark.

- Spread a thin layer of Vaseline in the black box in the center of each square with your finger.

After three days collect your data from the squares:

- Remove the squares one at a time. Each time, use your magnifying glass to count the number of visible particles you see stuck in the Vaseline inside the boxed area.

- Write the number in your data table.

- For each location you will have collected three sets of data, so you will want to average the data to get a better result. Add the three counts and write the number down. Then divide that number by three to get your average number.

The particles collected are what you are breathing in everyday. Many people are surprised by the number of particles collected. Which sites had the most particulate matter in the air? Were each of your three counts the same or different? What does this tell you about the air quality at each location?

Other project variations could include comparing air samples before and after a rainy day; are there less particles?

Though the number of particles collected can be alarming other environmental factors help filter the air such as plants. A NASA earth science study determined that indoor plants in a closed, controlled environment were able to extract pollutants from the air. The foliage of indoor plants was capable of removing low levels of pollution, while plant roots, assisted by an activated carbon filter, removed air pollutants at higher concentrations. These filters around plant roots removed and biologically degraded pollutants before they accumulated.

A follow up science project could be the study of plants in different locations to determine the amount of pollution in an area. Plants near industrial areas tend to grow slower and be less healthy because they are soaking up polluted particles in the area. The subject of dirty air and how it effects people and plants make great science fair project material that are sure to be a hit at your school science fair!