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Today in the show,

what are you breathing in when you do your hair?

When we think about air pollution, we think of smoke, we think of smog, we think of wildfires.

But we don't think of everyday hair care products to be causing indoor air pollution.

You've probably given some thought to outdoor air pollution.

Whether it's smog, from traffic or wildfire smoke, I suspect that many of us are checking

AQI measurements on our phone more than we used to.

But what about the air inside your house?

Today we're talking to a researcher who thinks a lot about indoor air pollution and how we create toxic air without even knowing it and how to avoid it.

Dr. Neustrot-Jong is a civil and environmental engineer at Purdue University in West Lafayette, Indiana, and she has a new study out on the toxins released during basic hair care.

Newstart, welcome to Science Friday.

Thank you, Flora. How are you?

I'm well. Let's brush up on your recent findings.

This is sort of where hair care products meet heat. What did you find?

Our study shows that routine hair-based styling can release billions of

nanoparticles into the air just within 10 to 20-minute routine. These particles are small enough

to penetrate deep into the lungs. So when we think about air pollution, we think of smoke, we think of smog, we think of

wildfires. But we don't think of everyday hair care products to be causing indoor air pollution.

...