Use this PBS NewsHour Student Reporting Labs video, “California community works to protect ocean” to shed light on the marine debris problem along our rivers and in our oceans. This video stimulates thoughtful discussions about the causes of trash in our rivers, lakes and beaches and what concerned citizens might do to be able to one day rediscover the natural spaces we once knew.
Science (Biology, Environmental Science, Ecology, Chemistry, Earth Science, Oceanography), Social Studies
Globally, plastic is the most abundant type of marine litter. This activity allows students to isolate and consider the environmental impact of microplastics in something they (hopefully) use every day: toothpaste. Manufacturers add tiny microbeads to the product to whiten teeth without scratching the surface of the tooth.
Materials (for groups of 2 or 3)
- Toothpaste containing microbeads: If polyethylene is present in the composition, microplastics are in the product
- Microscope or magnifying lens
- 2 glass jars or beakers
- Tap water
- Stirring rod or spoon
- Coffee filters
- Petri dish or acetate sheet (used to view the beads)
Warm Up Activity
Have the students work with a partner to:
- List the plastic products they used or came into contact with since they got up this morning.
- Discuss where plastic comes from and why the qualities that make plastic valuable to our culture also make it a menace to the ocean environment and its resources.
- Watch the PBS NewsHour Student Reporting Labs Video “California community works to protect ocean” (4:22), produced by students at Etiwanda High School in Etiwanda, California.
After watching the video, revisit the students’ list of plastics. We can all recognize strewn plastic cups, tableware, straws, shampoo bottles, fishing line, flip-flops and discarded toys along a beach. Students probably listed items such as toothbrushes, buttons, pens, notebooks, computers, cell phones or yogurt containers, to name a few. But how many of them thought to list the toothpaste, skin cleansers and cosmetics they may have used or the microfibers of fleece clothing they are wearing? These microplastics are small — less than 5 mm in diameter — but deadly to marine life. Taken in by filter feeders or eaten by zooplankton, they have entered the food chains creating a new and persistent type of aquatic pollution.
- Student should read labels to confirm the product contains microplastics.
- Squeeze the contents of the tube into the beaker or jar. Tube may need to be cut open and scraped out to get all the paste.
- Add tap water and stir the mixture to dissolve the paste components.
- Filter the mixture with a coffee filter from one beaker into another.
- Transfer the beads from the filter paper to the Petri dish or acetate sheet for observation with a lens or microscope.
- Describe and/or count the microbeads and then scrape them into a clean jar or vial for display. (Do not wash them down the drain!)
Note: Depending upon supplies, several groups may share one tube of toothpaste by cutting the tube into approximately equal sections or by measuring out 5 ml of toothpaste to each group. This can be done using a measuring spoon with a volume of 5 ml.
If time permits, further testing or calculations can be done:
- to determine the buoyancy of the beads in fresh and salt water
- to determine how many beads are present in a whole tube
- Tracking Trash: Imagine being able to help characterize the trash at your beach, your park, your stream, your lake or pond. Now a tracker app allows you to check in when you find trash in the waterways. Find out how you can make a difference by becoming part of a “citizen science” effort and have your data count. https://marinedebris.noaa.gov/partnerships/marine-debris-tracker
- 28,000 Rubber Duckies: Simply watching where objects travel in water led 18th and 19th century explorers to map major surface currents. Discover how modern day scientists, such as Curtis Ebbesmeyer, are putting objects washed ashore to work for them as they trace their journeys in ocean currents.
- The Voyage of the Plastiki: Drawing his inspiration from Thor Heyerdahl’s 1947 Kon-Tiki expedition, environmentalist David de Rothschild sailed 8,000 miles across the Pacific on a catamaran made of 12,000 plastic bottles. Find out how this team of architects, engineers, scientists and creatives came together to build a boat out of recycled waste products. This epic voyage is named the Plastiki. What materials were used in building the boat? How did the crew survive the four months at sea? What was the purpose of the expedition.
- Great Pacific Garbage Patch or Pacific trash vortex: Areas of the ocean where trash accumulates are referred to as “garbage patches.” Research why these “patches” exist. What physical properties of the ocean cause them to form? Where else do these “patches” exist in the ocean? What is the effect on plankton and other sealife? Why is the term “garbage patch” a misnomer? Learn more about these convergence zones in the ocean and the garbage patch issue by visiting the NOAA study of the North Pacific Subtropical Convergence Zone and the NOAA Marine Debris website.
- One Man’s Trash is Another Man’s Treasure: Works of art are being showcased around the country as they are being created to demonstrate our societies’ use of plastic. Visit these wildly creative, beautiful, and horrifying sculptures at Washed Ashore in Oregon or the Turtle Ocean exhibit at the National Museum of Natural History, Smithsonian Institution. Can you envision your own sculpture? The ocean depends upon our stewardship. Organize a volunteer shoreline clean-up where you and your group will carefully collect trash (always wearing gloves) and design your own work of art to inspire others to recycle or to limit their use of plastics.
Lisa Lyle Wu teaches marine biology and is Lab Director for Oceanography & Geophysical Systems at Thomas Jefferson High School for Science and Technology in Alexandria, VA. As a science writer, she develops curricular materials for Discovery Channel, Washington Post’s Newspaper In Education, and her own autonomous underwater glider program, as well as exhibit materials for the Smithsonian’s National Museum of Natural History. Wu is a recent Board Member for the Virginia Museum of Natural History. She thrives in coastal maritime life, residing in Arlington Virginia with her husband and son.
Standards NSES Science as Inquiry (A) 9-12
Students should develop: Abilities necessary to do scientific inquiry Understanding about scientific inquiry Life Science (C)
Students should develop an understanding of: Interdependence of organisms Science and Technology (E)
Students should develop: Abilities of technological design Understandings about science and technology Science in Personal and Social Perspectives (F)
Students should develop understanding of: Personal and community health Natural resources Environmental quality Natural and human induced hazards Science and technology in local, national, and global challenges
Science as a human endeavor (G) Natural history