1 Million Bottle Cap Challenge cultivates students’ curiosity in plastics recycling

In Stamford, Connecticut, nonprofit organization SoundWaters has empowered students to lead the charge against plastic pollution by recycling bottle caps. Started in 2019 by SoundWaters, the One Million Bottle Cap Challenge engages with an ambitious goal of recycling 1 million bottle caps within a school year, involving mostly classes of sixth graders at Stamford schools. Bob Mazzone, vice president of development, SoundWaters, says an item this small, yet common, has made an indelible impact on students’ understanding of plastic pollution.

SoundWaters’ mission is to kindle locals’ interest in protecting nearby Long Island Sound through education. Mazzone says when kids look at the water from the sound under a microscope at SoundWaters’ laboratory, they are distressed to discover it contains microplastics. SoundWaters set out to educate students about microplastics and was able to accomplish this thanks to a three-year grant from the National Oceanic and Atmospheric Administration.

The One Million Bottle Cap Challenge found inspiration in Mazzone’s past; it harkens back to his fourth-grade year, when his teacher challenged his class to collect 1 million of something, which became soda tabs. Since then, Mazzone says he has never forgotten that quest to collect a million of an item. Taking from Mazzone’s experience, the One Million Bottle Cap Challenge was meant to catch students’ imagination in the same way.

To make it more impactful for these students, SoundWaters told them that collecting 1 million bottle caps would prevent the equivalent weight of an entire car, or two to two-and-a-half tons, of plastic from entering Long Island Sound. Students quickly rose to the occasion.

“They attacked this, and the exciting part is that they did exactly what we were hoping they would do— they used their voices, they used their energy, they told their parents, they got their parents to tell their families and got their parents to tell their co-workers,” Mazzone says.

He adds, “And that was the entire objective of this project … to get students to play an active role, take initiative, use their voice, [and to] give them the agency to make an impact even as sixth graders … and they have seen the impact that they can make.”

Photo courtesy of SoundWaters

The program received widespread positive reception in and beyond Stamford. Other schools and businesses from Connecticut jumped in. An Arizona correctional complex and the Sitia UNESCO Global Geopark in Greece even became involved.

Mazzone says students were able to recognize how much plastic is used in their lives while preventing these bottle caps from reaching the sound.

“I don’t think that anyone will ever look at plastic packaging, plastic bottles, the same way and they will certainly never look at plastic waste on the ground the same way,” Mazzone says.

About 150 of the students worked with the World Design Organization (WDO), a global organization dedicated to the advancement of industrial design, he says. With the help of the WDO, students were tasked with designing a product following industry protocol that could be created from the plastic bottle caps. Designers from around the world, including France, Singapore and India, held video calls with them to plan a product for use in kitchens. The winning design created in the program’s first year was a countertop drying rack. In the following years, a plastic storage tub was designed as well. 

To manufacture the drying rack, collaboration among different companies and organizations was vital. Coordinating the backend of the program was Eve Vitale, chief executive of the Society of Plastics Engineers (SPE) Foundation, Danbury, Connecticut.

After being sorted by Norwalk, Connecticut-based Van Dyk Recycling Solutions, the bottle caps were sent to Portland, Pennsylvania-based Ultra-Poly Corp., which was able to handle metal contamination in some of the caps. Here, the polyethylene and polypropylene caps were ground separately and turned into pellets.

Kevin Cronin, vice president of sustainability at Ultra-Poly, says he videotaped the process for students.  It first involved loading caps onto a belt that leads to a grinder. The ground plastic went through elutriation, or separation by density, using an air flow table; this is where, for instance, paper liners in caps were separated from a plastic cap, Cronin says. The plastic finally was put into a single-screw extruder, melted and pelletized.

Cronin says the video of the process gave students an opportunity to see the challenges associated with mechanical recycling, such as when liners of metal caps accidentally get embedded within the plastic caps. However, it also got them to consider a future career in the recycling industry. Cronin says plastics education should focus on the fact that plastic is not intrinsically bad but an enabling resource.

“The real value of this is to be able to show kids that mechanical recycling does in fact work, and there’s infrastructure in place and it can make a difference,” Cronin says.

The team that won the design challenge worked with a Penn State Behrend student who developed a 3D-printed model of the drying rack and designed the mold used to manufacture it. Vitale says Penn State students who are a part of SPE manufactured the products. The resulting dish racks are continuing to return to Stamford for students and the public to keep.

Photo courtesy of SoundWaters

The collection tallies for the three years were:

• 2019/2020, 1,028,177 bottlecaps;
• 2020/2021, 643,999 bottlecaps; and
• 2021/2022, 812,338 bottlecaps.

Despite setbacks posed by the pandemic, Mazzone says students and teachers still were able to stay engaged with the challenge.

Since grant funding for the project has now expired, SoundWaters will no longer be accepting bottle caps. Mazzone says locals have contacted SoundWaters with questions about what to do with their bottle caps now that the program is over. Most notably, locals were confused on whether to recycle bottle caps by themselves or keep them on the bottle.

After researching the matter and hearing from community members, Mazzone says he realized that the answer varies depending on local recycling guidelines. Different communities, he says, have different recycling companies and recycling capabilities; some local guidelines tell people to take bottle caps off before recycling them, while others advise that bottle caps must remain on bottles when recycled. Mazzone says the lack of consensus on what to do with bottle cap recycling hints at a lingering problem that the recycling industry continues to face.

“You know, we didn’t choose bottle caps because they were contentious or in the middle of a storm. We chose bottle caps because they’re everywhere and people can relate to them. And they were small. It made it easier to handle, but it turned out, bottle caps tend to be a problem,” Mazzone says.

SoundWaters will continue to use lessons from the program in its education, he says. Vitale says SPE also plans to build on the success of the program since it already fits with the curriculum that the organization teaches across the country through PlastiVan, an education outreach program. PlastiVan covers numerous lessons related to polymer science, many of which are linked to the One Million Bottle Cap Challenge, such as thermoplastics and recycling and productive reuse of materials.

Vitale says the strongest takeaway for students is that plastic is ubiquitous. She has given students exercises to understand this reality, having them think of an activity that doesn’t involve plastic or imagine what a shopping trip would look like if all plastics in a store disappeared. Another crucial lesson, she says, is that plastic items like water bottles may be single use, but the material itself is not single use; it can be used to make a positive impact through product innovation and design for recycling.

“We hope that they will be advocates for responsible use of plastics and understand that the answer is not in banning or removing plastics from our society wholesale, but that together, scientists and engineers, and the public at large can and should work together to continually improve all aspects of plastics production and end-of-life solutions,” Vitale says.

She says the prevalence of plastics education programs in the U.S. is hit or miss. Through PlastiVan, she has found that certain regions have more of an interest in recycling than others. Regardless, expanding educational programs through PlastiVan, she says, is imperative.

For SoundWaters, problems related to climate science and microplastics must be approached by teaching students to use their voices.

“If we can teach kids about Long Island Sound, they will understand it. They will care about it. And you add those two together, and they will want to take care of it. ... in five years, 10 years, 15,20,25 years, they will be voting, they will be making decisions. They will have their own children. And so, the compounding effect of education is immense,” Mazzone says.