Microplastics are:

Any piece of plastic 5mm or smaller. Alarmingly ubiquitous.

Plastic particles, ranging in size from millimeters to nanometers are profoundly abundant in our oceans, the air we breathe and the food that we eat.

3D printers are specifically built to produce brittle plastic fibers less than a millimeter in diameter.

Scientists have found microplastics virtually everywhere that they look. They’re found in rain in the Rockies and in snow in the Arctic. Bits of plastic are in most seafood, every Beluga whale tested and recently found in honey. There are even particles on your skin and the inside of you right now.

If you are a 3D printer enthusiast like myself then you likely produce and consume even more of these tiny invasive bits of plastic than most people. Waste from electronics has been a persistent and well-known problem, but unlike a computer, these devices are miniature plastic manufacturing plants. In this case, the problem is not the electronic itself, but just using it as intended. No matter the type of filament you use, both printing and the print itself contribute to this problem.

First, let’s look at what’s happening while you print.

In studies focusing on desktop-style 3D printers, tests concluded that all of them emit both UFPs (Ultra Fine Particles) and VOCs (Volatile Organic Compounds). The amount released varies depending on the color and brand of filament, and the printer itself. Both UFPs and VOCs are often also microplastics.

A study (since been replicated with similar results) tested common models of 3D printers and using that, let’s look at ultrafine particles first.

UFPs are particles smaller than 100 nanometers. They are released in the air when melting thermoplastics and are so small that they can be absorbed through your skin if you don’t inhale them first.

In this test, all ABS brands had high UFP emissions and PLA was at the low end of this spectrum with 108 particles/cm3.

Fewer UFPs are released while cooking with a gas stove. On high heat, a gas stove will release 106 particles/cm3 of non-plastic UFPs. Whats released from a 3d printer is even smaller, a third the size of a virus, and more concentrated. A stove also often has a ventilated hood, isn’t on your desk or in your bedroom and doesn’t run for so many hours on end.

The health concern from UFPs isn’t immediate- that doesn’t mean it isn’t there. Particles at that size don’t easily leave your lungs and can be made up of all kinds of compounds. What doesn’t enter your body, builds up as microscopic dust on surfaces in your house instead. Eventually, they find their way outside and into our biosphere.

Now let’s take a look at VOCs.

These compounds are relatively common gasses but the styrene produced by ABS is particularly toxic and a possible carcinogen. Styrene can affect the central nervous system, cause depression, headaches, concentration problems, fatigue, nausea, drowsiness, irritation of the eyes, nose and throat, and chemical pneumonitis.

PLA was the only filament to not produce hazardous compounds. The lactide it did release is safe for humans, but not wildlife as it is also a massive contributor to marine pollution. However, PLA did release some methyl methacrylate, an irritant in larger quanitites.

As demonstrated, ABS creates the most of both pollutants and PLA, popular partly for this reason, emitted far less. The quantities of each were still low enough to not be an immediate health risk.

The point is, this is not “nothing” and these other, invisible byproducts are invasive. If you don’t keep your printer in a sealed enclosure and with a HEPA and charcoal filter, these UFPs and VOCs will find their way to the furthest reaches of the Earth.

Now let’s talk about the print itself.

Due to the nature of how 3D printed objects are built, once thrown away, they almost immediately begin to breakdown into particles 5mm and smaller. They are intentionally constructed by fibers smaller than that. Meaning, they turn into microplastics faster than other plastic waste.

Recently, China stopped purchasing mostly all recycling from the United States, inclduing the plastics used in 3D printing. This means that even by throwing your failed prints into the recycling bin, they will still end up in a landfill and therefore the ocean.

The “most biodegradable” filament, PLA, takes two years or more at 140ºF in an abiotic medium to decompose safely. These conditions are only met in industrial composting facilities, not landfills. Your local recycling facility most likely won’t take them either- and so they stay, getting smaller and more numerous over time.

Fundamentally, microplastics are non-toxic to animal life but they easily can and do absorb them. It’s inherent in their composition. The low weight particles then become transmitters of an endless list of pollutants that spread everywhere.

Microplastics have been found in hundreds of species and on every continent, despite the fact humans have only been using these materials for 50 years. Although virtually non toxic, problems are already starting to show.

A thing doesn’t have to be toxic to be harmful. For instance, earthworms and other annelids eat these particles, confusing them with soil and effectively starve themselves. Earthworms are as vital to our ecosystem as honey bees, who’s declining population also ingest these particles every day.

An Incomplete List of Where Microplastics Come From

All plastic waste

Manufacturing Emissions

Cars and Tires

Clothing

Labs/ Hospitals Soaps

Beauty Products

Processed Foods

Fishing/ Boasting Industry

Street Paint

You Actually Can Do Something About It

It’s important to remember that these are really small numbers. 3D printing is by no means a large contributor to microplastic waste, just a silent one. It’s about time we ask a little more of manufacturers- industrial and at home. Besides industry regulations of some kind, here are 3 suggestions to be a more environmentally conscious 3D printer at home.