All the News That’s Fit: Hair’s hidden history, C-section pioneer and Bieber Fever

For The Union-Tribune

Every hair tells a story — if you have any

New research shows that hair can capture a chemical record of human exposure across days, week and even months. Writing in the journal Chemical Research in Toxicology, scientists at the University of Texas analyzed snippets of hair and found that for at least one chemical — a class of common endocrine-disrupting plasticizer called phthalates that are often found in household materials and personal care products — levels matched back to different time exposures.

Most exposure studies rely on urine or blood, which fluctuate daily and capture only recent exposures. By contrast, hair grows slowly and steadily, incorporating compounds into its structure as it forms. Every half inch represents about a month of chemical history.

Part of the researchers’ message is that exposure to harmful substances doesn’t just come from smokestacks or car exhaust. Americans spend roughly 90% of their time indoors, where pollutants from cooking, furniture cleaning products and even our bodies often dominate. Simple habits like vacuuming more frequently and avoiding personal care products that contain phthalates can lower exposures.

“Even knowing that before going to bed, just opening the windows for a few minutes and flushing the house with some fresh air, [your] exposure can really be much smaller,” said study co-author Pawal Misztal.