Did you know that plastic bags are used for an average of 12 minutes? That?s a really short amount of time — especially considering plastic bags have a life-span of 1000+ years in the landfill. I?ve tried to eliminate plastic bag usage from my life and encourage others to do the same.

This fall, I?m helping implement a school-wide paper and plastic bag recycling project in my school as well as presiding over a campus-wide campaign to eliminate plastic bags from our school store. As I?ve seen in other schools as well, campus-wide campaigns that encourage students to adopt eco-friendly habits are, in a way, environmental education. Through my environmental efforts in China, I?ve learned that environmental education can go a long way in changing other peoples? behaviors and urging them toward a more sustainable lifestyle, so I?ll share some important information about plastic bags here:

The process of creation and associated harms

The most plastic bags or plastic items are made from basically petroleum and natural gas, which are then separated and converted into different types of polymers. Polymers, which are large molecules that comprised of monomers, are used in a variety of ways to make ethylene. Ethylene is then used to create a chemical call polyethylene.

            There are three types of polyethylene that make up typical plastic bags: high-density polyethylene (HDPE), low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE). HDPE and LDPE plastics are created through Ziegler-Natta vinyl polymerization (which I won?t explain here, but this article explains it well enough for me: http://chemwiki.ucdavis.edu/Organic_Chemistry/Polymers/Synthesis_of_Addition_Polymers#Ziegler-Natta_Catalytic_Polymerization ). When ethylene and polyethylene are created, carcinogens are released into the atmosphere, which can contribute to the onset of cancer in humans and animal who breathe the air.

            Different types of bags are created through changing the molecular chain is polyethylene pellets. By pounding pellets heated to 200 degrees Centigrade, one can create molten pellets that can be pushed through an extruding machine to create a bag. In order to be sent through the press, the polyethylene chain must be divided, which weakens the strength of the plastic created.

           

Different types of plastics: This is what the number on your plastic bottle means!

 

1) POLYETHYLENE TEREPHTHALATE (PET OR PETE)

Common uses: soda bottles, single-use water bottle containers, cooking oil bottles, peanut butter jars. This is the most widely recycled plastic.

Commonly recycled. It's best suited for single-use containers, since it can break down when exposed to light and heat.

 

2) HIGH DENSITY POLYETHYLENE (HDPE)

Common uses: detergent bottles, milk jugs.

HDPE is a sturdy and reliable non-leaching translucent plastic. HDPE resists UV penetration and can withstand temperatures from -148 to 176?F (-100 to 80?C).

 

 

3) POLYVINYL CHLORIDE (PVC)

Common uses: plastic pipes, shrink wrap, water bottles, salad dressing.
Most PVC vinyl products contain phthalates, which mimic human hormones and can affect various life forms including fish and invertebrates. Not recommended for food storage.

 

4) LOW DENSITY POLYETHYLENE (LDPE)

Common uses: dry cleaning bags, produce bags, trash can liners.

Safe, doesn't leach. Safe for use with food and beverages.

 

 

5) POLYPROPYLENE (PP)

Common uses: bottle caps, food containers, drinking straws.
BPA-free. resistance to high heat

 

 

6) POLYSTYRENE (PS)

Common uses: Also known as ?Styrofoam,? used in packaging pellets, cups, disposable tableware, take-out containers.
Toxic to marine life when in the ocean as Polystyrene foam. The majority of Polystene is not recycled.

 

 

7) OTHER

Common uses: Tupperware, CD ROMs, Car parts, water cooler bottles

Includes polycarbonate, which is proven to leach BPA and not recommended for food storage. Usually all plastics in this category are difficult to recycle.

 

What about biodegradable plastics?

Microorganisms can convert biodegradable plastics into water, CO₂, and biomass without residual chemicals. Beware of ?biodegradable?! Many people have attempted to make profits off of the idea that biodegradable plastics are more eco-friendly, but it?s always best to evaluate how much more eco-friendly these plastics are before jumping on the bandwagon.

Contrary to my previous belief, biodegradable plastics, as well as other trash, usually does not biodegrade in a landfill. If biodegradable plastics do degrade in the anoxic environment, methane, a potent greenhouse gas, is released into the atmosphere.

Biodegradable products do not just go away once you through them away. In the best-case scenario, they are sent to a commercial composting facility, where microorganisms can eat them away. It?s best for the environment if we are aware of whether our community has such a recycling facility before buying a lot of biodegradable plastics.

 

Viable alternatives to plastic bags:

Reusable/cloth shopping bags

Glass jars, China bowls/ kitchenware

Starch-based polymers

 

Ways you can take action or continue to take action:

Start a plastic bag campaign at your school, in your community, or through social media! Post a video of you and some friends doing work for the environment on Youtube or another social media site/ video-sharing site to encourage awareness of the issue and spread environmental education.

 

I hope you enjoyed this two-article series on green living. Feel free to offer suggestions or comments below. Let me know also if you'd like to see sources!