[light upbeat music] - [Narrator] You probably don't think about it, but plastics make our world, well, go.

And it's not just the plastic in a vehicle.

Almost everything in this bedroom contains some synthetic fibers, from the fur on the teddy bear to the book covering to the bedsheets and clothes.

Same is true in the kitchen.

Cooking utensils, food containers, dishes all contain plastic.

Workplace, same thing.

There's so much plastic in our world, we take it for granted.

- Plastic is just about anywhere you can imagine, especially when we think about how small plastic can get.

- [Narrator] But it turns out, when you use something made of plastic, microplastics break off.

- A microplastic is essentially a small piece of plastic.

It's smaller than five millimeters, which is the diameter of a pencil eraser tip.

So anything smaller than this is considered a microplastic.

Even the process of opening a chip bag has been shown to release microplastics, or the process of even cutting open a bag can release microplastics, or the process of opening the bottle cap is a process of releasing microplastics.

The clothes that we wear, the majority of them are made of synthetic plastics.

And so the moment that we wash those clothes, we can be releasing microplastic fibers.

- [Narrator] Imari Walker-Franklin and the researchers at RTI International are finding microplastics everywhere.

- [Imari] Things like microplastics and nanoplastics are small enough to travel all over the world, whether through our air, within our waters, or even in things like our dirt or just in the bodies of other organisms.

- [Narrator] And those bodies include people.

Yes, there are microplastics inside you.

- Just about anywhere that we look in the human body, we're finding microplastics.

We find it in human feces, we find it in the placenta, we can find it in the digestive tract.

We found it in lung tissues.

We've even found that there's capability for nanoplastics, which is even smaller than a microplastic, to pass through the blood-brain barrier.

Now, when we think about blood itself, we can find that nanoplastics are embedded in the veins or being transported in the blood.

- [Narrator] There are 10,000 different chemicals associated with plastics either to make the plastic, protect the plastic, or give it special properties.

So the basic question is what effect microplastics have on people?

- We can breathe in these microplastics.

We are eating these microplastics.

We're not really sure from the particle itself if there could be harm.

Some of these microplastics can have different morphology, different shapes, sizes.

Some can be kind of jagged and cause, you know, physical impacts.

And then the other issue is that these plastics carry chemicals in them, and those chemicals can be released into the body.

And we don't really know if that there's individual toxicity of those chemicals or even the mixture of those chemicals being released causing harm.

So for at least mechanical recycling, what they do is they usually wash the bottles out to get all the contamination out as much as possible.

And then they start to shred them into smaller pieces so that they can reheat them and mold them into a new plastic product.

So we caught them mid recycling and we just took those bags, and then we put them on basically like a sieve.

Like, you know, if you take a... Like, if you go to the beach when you, like, try to filter through the sand or you're gold mining, we have some those similar tools to get them into different sizes, because it really depends on the size where it ends up in the body.

And then we're putting those into media that's used to feed human cells, human lung cells in particular.

And we wanna see what are the effect of that leachate of those particles on the human lung cells.

All of these, the green, the yellow, and the white, they are the exact same plastic type.

These are high density polyethylene, but they were all just used for different products.

So it really speaks to the fact that you can have the same polymer type, but they can even physically look different because there's different chemicals placed inside them, like dyes and colorants used to make the plastic itself.

So we really wanted to see if those made a difference on the toxicity or the types of chemicals being released.

So in this study, we put them in extracts to analyze them on a mass spec to look at and identify new emerging contaminants inside of the extracts.

- And so once you stir it around for a while, you're gonna take a look at the extract and see what has leached out, basically.

- Exactly.

- [Narrator] This is what microplastic pieces of tire rubble look like when they are placed onto human lung cells.

The darker, irregular shapes are the tire fragments.

The blue dye highlights healthy cells.

But watch what happens.

The green dye highlights cell death.

Just what is killing those cells is what researchers are trying to figure out.

- These are things that need to be studied further to see if the chemical is driving the toxicity or if the particle is driving the toxicity.

- I do worry about our children.

I worry about the future generation because plastic is not going away.

It takes hundreds of thousands of years.

We don't even know if they're gonna return to a state in which it's not gonna be harmful.

There's so many unknowns about the effects on human health.

- [Imari] I think that there's still a lot of things that we need to figure out concerning, you know, what are the true impacts for plastics, you know?

Is it chronic exposure that's gonna be the problem?

Is it a certain concentration that's gonna, you know, cause, you know, even worse effects?

But you know, there are things that we can still do now to address plastic pollution itself because microplastics come from plastics.

So we have to think about are we using plastics for the right reasons?

Are there unnecessary, avoidable, and problematic plastics that we can readjust and change, you know, our formulations, or even alter to different material types?

Because plastics didn't exist until the 40s.

You know, we didn't live a life with plastics, you know, until very recently, you know, within the last few generations.

So while it's hard for us now to imagine a life without it, there was life without plastics.