Last month, the world celebrated Earth Day with a promise to #EndPlasticPollution. And while cutting down on single use items like plastic bags or bottles (in 2016, single use plastic bottles amounted to 480 bottles sold globally) may go a long way to reduce plastic waste, others have found novel ways to make plastic waste useful.

These are just five ways that plastic waste can be put to good use.

1. Plastic Waste = Stronger Asphalt

Plastic waste can be used to reinforce asphalt roads. CC Michaal Pollak.

Plastic waste can be used to reinforce asphalt roads. CC Michaal Pollak.

Earlier this year, a study looked at how plastic can be added to asphalt mixtures to augment the paving of Ghana’s roads, effectively addressing two of the country’s most pressing challenges. The study posits that, with the capital Accra producing an average of 3,000 metric tons (three million kilograms) of trash daily, using plastic to fix the country’s many pothole-ridden roads can simultaneously reduce the massive amount of trash on Accra’s streets.

While this proposal may seem novel in Accra, the West African city is not the only one looking to plastic for smoother driving. In 2016, India’s state-owned Clean Kerala Company announced an initiative to buy plastic waste from citizens and then use that plastic for road construction in Kerala.

The Kerala government went on to mandate that every municipality within the state use recycled plastic in at least 10 percent of roads laid in its jurisdiction. According to Amole Bale, Assistant Professor in the Department of Chemical Engineering at Bharati Vidyapeeth Deemed University, including plastic in road paving mixtures can decrease moisture absorptive capacity, improve compressive strength and flexural strength, and make the roads twice as strong as normal roads.


2. Plastic Bottle Homes

On the other side of the pond in Panama, a 2016 project led by Robert Bezeau aimed to build 120 homes completely from discarded plastic bottles. The idea, which stemmed from an environmentally-conscious decision on the part of Bezeau to address the difficulty of breaking down plastic, was implemented in Panama’s Boco del Drago and promised eco-friendly and disaster-resistant homes to residents.

Each home was constructed using approximately 14,000 plastic bottles fastened within mesh metal cages, which provide natural insulation and flexible walls, meaning the houses only sway rather than crumble in case of an earthquake. Bezeau even proposed that should a tsunami hit, the plastic homes can even be used as rafts due to their buoyancy.


3. Recycled Plastic Brick Shelters

In Colombia, Conceptos Plásticos (Plastic Concepts), founded in 2011, spent years experimenting with plastic bricks before building a set of temporary shelters out of recycled plastic brick in the southwest Colombian City of Guapi. The shelters served as homes for 42 families who were displaced due to armed conflict. The project was completed in 28 days and used more than 200 tons of recycled plastic in 2017.

The company’s decision to make the bricks out of used plastic rather than new plastic doubled the challenge for Conceptos Plásticos, which used discarded plastic from recyclers and factories. The plastic was melted and emptied into a mold similar to that used for clay bricks, to create three-kilo (6.6 pound) bricks.The bricks were then assembled like LEGO pieces to create buildings up to two stories high. Because of how they are assembled, the bricks insulate heat, are thermoacoustic and earthquake-resistant – key for a country like Colombia, which has high levels of seismic activity.


4. Plastic-Reinforced Concrete

Graphic of a concrete block made with radiated plastic waste. CC: MIT News.

Graphic of a concrete block made with radiated plastic waste. CC: MIT News.

The second most used material on the planet after water, concrete is responsible for 4.5% of global carbon emissions. The increased usage of concrete poses two main problems globally: the number of deaths in the construction industry and its contribution to carbon emissions.

Late last year, undergraduate and graduate students at MIT came up with a solution that simultaneously addresses carbon emissions from concrete and plastic waste: concrete reinforced with radiated plastic. Using plastic bottles usually used for soda or water bottles, the researchers pulverized plastic flakes with gamma rays until they were ground into powder. They then added them to concrete mix, creating concrete that is stronger than the ready-mix concrete used around the world today.

The researchers also found that emissions produced by the concrete were reduced by about 0.0675% for the sample that they worked with – a reduction that came from swapping a mere 1.5% of concrete without plastic with concrete mixed with radiated plastic.


5. Plastic Blankets To Warm The Homeless

Tennessee Bag Ladies make blankets out of plastic bags for the homeless. Courtesy of Second Baptist Church Bag Ladies.

Tennessee Bag Ladies make blankets out of plastic bags for the homeless. Courtesy of Second Baptist Church Bag Ladies.

In 2015, a group of elderly women in the American State of Tennessee turned over 10,000 discarded plastic bags into sleeping mats for the homeless. The ladies, who meet regularly at the Second Baptist Church in Union City and go by the moniker the “Tennessee Bag Ladies, crocheted over 165 mattresses over two years.

The ladies cut donated plastic bags into strips and tie them together to create a plastic yarn, which they then crochet together to make a sleeping mattress – a process which takes up to two weeks.

Janice Akin, a 66-year-old member of the Tennessee Bag Ladies, told ABC  that it makes them “feel really blessed to be able to do this. “I know it doesn’t sound like much, but it’s a good feeling to know you’re helping someone — even if just a little bit.”