Which Packing Material Is Biodegradable – An Ecology Investigation

It’s always fun to receive a package in the mail, but have you ever looked at the packing materials around the items inside the package? Their only purpose is to take up space. What happens when you throw them in the trash? Which type of packing material is biodegradable and which just takes up more space at the local landfill? This packing materials experiment will help you find out.

Biodegradable material can be broken down by living organisms, such as the organisms found in garden soil. Material which cannot be broken down in this manner is called non-biodegradable. This experiment helps student investigate the differences between various types of packing materials.

This would be a good experiment to do in the days leading up to Earth Day.

Which Packing Material Is Biodegradable?

Materials

• Garden trowel
• Measuring cup
• Plastic ziploc bags
• Garden soil
• Sand
• Assorted packing materials – foam packing peanuts, plastic inflatable packing material, plastic bubble wrap, popped popcorn, shredded newspaper, etc
• Marker
• Water

Instructions

1. Use the garden trowel to put one cup of soil in each bag.
2. Add one cup of sand to each bag.
3. Gently mix the sand and soil in the bag.
4. Place a few pieces of one type of packing material in each bag. Try to put approximately the same amount of material in each bag.
5. Use the marker to label the bag with the type of material which is in it (ie packing peanuts, popcorn, newspaper, etc.)
6. Add additional soil so each bag is full almost to the top.
7. Add 1/2 cup of water to each bag.
8. Close each bag.
9. Set the bags in a sunny window for two days.
10. Open the bags, stir gently, add another cup of water, and reseal the bags. Put them back in the sunny window.
11. After three days, open the bags and examine the contents.

Discussion

Pick through the contents of each bag. It might help to spread it out on a large piece of plastic. Which materials decayed and which stayed the same? What does this tell you about what happens to the packing materials you throw away? Do the materials which decayed have anything in common? Did the materials which are not biodegradable have anything in common.

Future Study

• Try it again, allowing even more time for the materials to degrade.
• Try the experiment with additional packing materials.
• Try it again with little or no dirt. What does this tell you about the importance of landfill design?