We're All a Little Plastic on the Inside

You're made of water, bone, blood, muscle and fat; you're also a few parts plastic. That is, if you prefer sea salt on your meal. Or honey, shellfish, beer or tap water. Recent studies have found microplastics, tiny shards of degraded plastic, in them all. Even the air is filled with the minuscule plastic bits.

Hold off on the panic though; it's still too early for researchers to say what the effects of microplastic consumption are, although studies in animals suggest that they can certainly cause harm. 

In humans, though, it's a bit harder to study because nearly everyone has microplastics in their bodies, so there's no control group for comparison. The pieces themselves seem relatively benign — they're just tiny bits of plastic, looking in large quantities like so much sand, created as larger plastic objects gradually degrade.

NOAA defines a microplastic as anything plastic under 5 millimeters — large enough to see easily with the human eye, although many can be microscopic. Most are small enough to pass through the digestive system without causing harm, but they can also hold on to and deliver pollutants inside our bodies, something the animal studies supported.

Read More: Microplastics Are Everywhere. What Are They Doing to Our Health?

There's been evidence that microplastics have been infiltrating our bodies for a few years now: A 2013 study found them in German honey and sugar, 2014 saw them pop up in some shellfish and beer. Researchers also examined salt — a 2017 study found microplastic particles in 16 of 17 brands of sea salt.

In most cases, the levels of microplastics were quite low — with the notable exception of shellfish. Regular and even excessive consumers of salt, beer, and honey will only ingest a few thousand particles a year at most from those sources, and we'll never notice their fleeting passage. The point though, is that these products come from very different places, which is an indication that microplastics are far more pervasive than we might think.

Plastic in the air brings new concerns as well, as it can enter the lungs and spread through the environment more readily. And those shellfish? The study found the average European could consume up to 11,000 pieces of microplastic from them annually.

Read More: How Microplastics Sneak Into Our Bodies

Although the impact of microplastics on our health aren't settled, their ubiquity is a growing concern. It will likely only get worse, too. We generate more than 380 million tons of plastic annually, the majority of which has ends up as trash. We're on track to have thrown around 13 billion tons away by 2050, and that will only translate into more microplastics.

An international team of researchers estimated in 2014 that there are around 5 trillion pieces of plastic floating in the ocean, weighing 250,000 tons. Bit by bit, it will break down and make its way back to us.

Read More: The Fight Against Microplastics

Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:

• PeerJ. Harmful effects of the microplastic pollution on animal health: a literature review

• National Oceanic and Atmospheric Administration. What are microplastics?

• Food Additives & Contaminants: Part A. Non-pollen particulates in honey and sugar

• Food Additives & Contaminants: Part A. Synthetic particles as contaminants in German beers

• Scientific Reports. The presence of microplastics in commercial salts from different countries

• Environmental Pollution. Microplastics in bivalves cultured for human consumption

• Plastic Oceans. Plastic Pollution Facts 

• Recycle Nation. Plastic Waste Will Top 13 Billion Tons by 2050

• PLOS ONE. Plastic Pollution in the World's Oceans: More than 5 Trillion Plastic Pieces Weighing over 250,000 Tons Afloat at Sea