Material selection is of utmost importance not only for product viability and performance, but also for long-term impacts that can create new problems later. Our global plastic usage has been causing significant issues in our water supplies for decades, yet the problem, or at least its severity, is still not common knowledge, nor is there a socially embedded sense of urgency to address the concern.
Research on how plastics navigate the Earth through environmental and biological systems reveals that we’re too late to reverse contamination, but we can certainly manage the flow and mitigate impacts. In a recent study, scientists recorded and measured in real time how fast microplastics move through the gut passages of copepods (a zooplankton species) to estimate how fast they may transport plastics up and down the water column. Watch this clip from the Plymouth Marine Laboratory of real-time imaging of microplastic gut passage in zooplankton:
Typically, plastic pollution is viewed as a surface problem, with visuals of crumpled water bottles and grocery bags riding currents and cluttering beaches. But now we have evidence that innocent copepods may be a major microplastic transport mechanism, embedding plastics into the seafloor and marine food web. Land animals and humans are not removed from marine systems, as researchers have detected microplastics in our food and bodies, expanding environmental concerns to potential global public health problems.
This is not a hippie-dippie way of thinking. It’s practical, data-driven, and essential, which is why we have worldwide initiatives for ecosystem restoration and environmental responsibility. But what does all this mean for the design engineer who knows that plastic is likely the cheapest, most durable, and easiest material to source reliably for their products to be manufactured at scale?
As engineers, every design decision needs to meet certain criteria to achieve performance, durability, and other factors, but when you start thinking more broadly, considering the end-of-life of a product is critical.
Though most visible and measured plastic pollution is attributed to consumer products, industrial sources play an underappreciated role, especially upstream and at smaller particle sizes. Industry has a unique advantage to more efficiently recapture scrap and used materials still of good quality to recycle and repurpose for further industrial applications. Dozens of companies we cover in Design World have recapturing programs in place so that industries can leverage the benefits of plastics and other materials while recovering them responsibly. Such programs help engineers make design decisions that meet functional and business requirements without escalating broader concerns. Plus, they align with design for manufacturability (DFM) principles aimed to reduce costs, improve quality, optimize processes, and eliminate waste.
There’s no perfect solution here, but I challenge you to think on it. If you’d like to think on it together, message me and let’s have a discussion. Also, stay tuned for more ponderings like this as we cover DFM principles and applications in an upcoming special report and webinar series.
In the meantime, if you’d like to expand your perspective on plastics, I highly recommend reading these Technical Thinking columns by fan-favorite Mark Jones:
- Let’s not do spatulageddon again — Don’t trash those plastic spatulas
- Get your Raman microscopes out — Nanoparticles in water
- This one breaks my heart — The long road to Lego sustainability
- Who’s got two thumbs and pollutes the Earth — The problem is not plastics, but us
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Sources:
Biological pumps: how zooplankton are transporting microplastics to the ocean depths
Real-time visualization reveals copepod mediated microplastic flux
Filed Under: Commentaries • insights • Technical thinking
