- Human hair can record many different chemicals over time in people.
- Hair grows slowly over many weeks and months.
- A small lock of hair can show past exposure for a person.
- Scientists heat hair to release trapped chemicals.
- A machine in the lab measures the released molecules.
- Researchers found chemicals from plastics and cigarette smoke.
- Most pollution comes from indoor activities and products.
- Simple steps can reduce exposure at home.
Difficult words
- record — save information so it can be seen later
- exposure — when a person is near harmful chemicals
- release — let something come out from a place
- measure — use tools to find the size or amountmeasures
- pollution — dirty or harmful substances in air or water
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
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