This is scientific American 60 second science. I'm Annie Snead.

Plastic is lightweight, malleable, durable, but it has also become so widespread that it's ending up in a lot of unwanted places, including our own bodies.

That's according to a new study which found that humans are consuming a shocking amount of so-called microplastics.

Microplastics, the kind of current working definition is plastic less than 5 millimeters.

So people commonly equate that to something like a grain of rice or a sesame seed and down in terms of size class. I will say that most of

microplastics that people are interacting with are quite a bit smaller than the

sesame seed size which I think always kind of shocks people when we start

talking about the numbers because they kind of can't you know they can't see a lot

of these things at least with the naked eye.

Kiran Cox, a PhD candidate in marine biology at the University of Victoria in Canada

and one of the authors of the study which is in the journal Environmental Science and Technology.

Microplastics come from numerous sources.

They can be shed from larger plastics or they may have been designed small to begin with.

Further study, Cox and his team pulled together past scientific literature

that calculated the number of microplastics and things we commonly consume,

such as in tap and bottled water, sugar, seafood, even in the air that we breathe.

This analysis helped them figure out the baseline amount of microplastics that people are consuming every year. They couldn't include

common foods like beef, poultry, vegetables, and dairy in their analysis because data

on them doesn't exist yet. In fact, their study could only account for 15% of people's caloric intake.

Even missing the majority of what people swallow, the research revealed that at the very least humans appear to

consume somewhere between 74,000 and 121,000 microplastic particles every year.

That number goes up for people drinking bottled water rather than tap water.

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