Dust, Skin and Other Ways In

By Robert O'Neal. A 5-part series on breathing PFAS dust from fields, getting it on your skin, and the other ways it gets into your system.

Part 1 of 5: More than food and water

When people talk about PFAS getting into us, they usually mean drinking water and food. Those are still the main ways in for most people.

But if you work land that was spread with sludge, there are other ways too:

• Breathing the dust.
• Getting it on your skin.
• Swallowing dirt off your hands without knowing it.
• Carrying it home on your clothes and boots.

Most of the health rules were written with water and food in mind. Farmers, farm workers and families who live next to these fields get the extra routes on top of that.

The next parts take these one at a time.

Part 2 of 5: Breathing the dust

Most PFAS don't evaporate into the air the way gasoline does. That's why health agencies say breathing them is not a typical route for most people.

ATSDR also says that people who handle PFAS materials at work and breathe the dust can be exposed that way. A field spread with sludge is that kind of workplace.

In 2022 researchers looked at the data and found that dust blowing off fields spread with biosolids could be loaded with PFAS and microplastics. Microplastics get picked up by the wind more easily than regular soil.

Another study sampled the air around fields where biosolids were spread. The particles were small enough to get deep in the lungs. They were found about 560 feet downwind of a field being disked.

Once PFAS are in your lungs, they get absorbed into the body. Scientists expect the same harm as swallowing them, because they end up in the same organs: liver, kidneys, thyroid, blood.

Here is the gap. EPA has never set a safe level for breathing PFAS. Without one, nobody can officially figure the risk. So this route mostly goes uncounted.

Part 3 of 5: On your skin

For years the official line was that PFAS don't get through your skin much. CDC's guide for doctors called it of minimal concern.

In 2024 researchers at the University of Birmingham in England tested 17 PFAS on lab-grown human skin.

15 of the 17 got through in real amounts.

For PFOA, 13.5 percent went through into what would be the bloodstream. Another 38 percent stayed in the skin, where it could soak in later.

The short-chain replacements got through easier. One of them was absorbed about four times more than PFOA.

To be fair about it: the chemicals were mixed in a solvent and left on lab skin for a day or more. That's not the same as dirt on a farmer's arms. The study shows the door is open. It doesn't say how much gets through from soil.

But it means the old answer, that skin keeps it out, doesn't hold up.

Part 4 of 5: Hand to mouth, and taking it home

The way most field dirt gets into you is simple. You swallow it.

• Eating a sandwich with dirty hands
• Wiping your mouth with your sleeve
• Smoking or chewing in the field
• Dust you breathe in that gets coughed up and swallowed

Swallowed dirt counts more than dirt on your skin. New Hampshire's environmental agency, when it sets safe levels for PFAS in soil, assumes all of it gets absorbed when swallowed and about a tenth of it through skin.

Then there's what comes home. Dust rides in on boots, clothes, hats and truck seats. It settles in the house.

Kids are the ones who pick it up most. They are on the floor, they put their hands in their mouths, and researchers note small children breathe in stirred-up dust in bigger amounts.

Part 5 of 5: Protecting yourself and your family

None of this means you can't work your land. It means taking the same care you would with any farm chemical.

In the field:

• Wear an N95 mask when disking, bush-hogging, or working dry, dusty ground.
• Keep the cab closed and the air filter changed.
• Wet down dusty areas when you can.
• Wear gloves and long sleeves.

Before you eat or go in the house:

• Wash your hands and face.
• Change out of work clothes and boots at the door.
• Wash work clothes separately from the family's.
• Keep kids and pets off fields that were spread with sludge.

These steps cost little. They cut down the dust that gets into your lungs, your mouth and your home.

And keep testing. Water, soil, and if your doctor will order it, your blood.