Elephant seal pups rack up PFAS while nursing

By Carolyn Wilke | C&EN | June 19, 2026

Read the full article by Carolyn Wilke (C&EN)

"Northern elephant seal females and pups go through intense cycles of fueling and fasting. Thanks to extremely fatty milk, pups gain 4 kg a day in their roughly 4-week suckling period. They then fast for 2 months, relying on the fat they have stashed until they are able to dive for their own food.

A new study indicates that seal mothers pass down significant amounts of per- and polyfluoroalkyl substances, or PFAS, to pups in their milk during this intense feeding period. Blood tests also showed that PFAS concentrations continued to increase in pups after weaning (Environ. Health 2026, DOI: 10.1021/envhealth.5c00782).

This “contamination in animals that are foraging way out in the middle of the ocean reflects a level of background contamination that’s frankly terrifying,” says Jane Khudyakov, a comparative physiologist at the University of the Pacific."