Are water-repellent rain jackets pushing up your blood PFAS?

What's actually in it

Many rain jackets use PFAS (per- and polyfluoroalkyl substances) to create a water-repellent coating. These are often called "forever chemicals" because they don't break down in the environment or your body. When you wear these clothes, you can be exposed to these chemicals through skin contact or by breathing in particles that shed from the fabric.

Once they enter your system, they don't just disappear. They accumulate in your blood over time. As shown in a 2026 study in Environ Sci Technol, researchers have been tracking both legacy and newer forms of these chemicals in human blood for nearly two decades.

What the research says

A 2026 study in Env Sci Adv found that higher levels of PFAS in human blood are directly linked to elevated blood lipid levels. This means your body's fat levels in the blood can rise when these chemicals are present.

The risks go beyond just blood fats. A 2026 study in Environ Res looked at pregnancy and found that high PFAS exposure is linked to changes in blood pressure during pregnancy. Furthermore, a 2025 study in Front Toxicol shows that exposure to these chemicals during pregnancy and breastfeeding can change how the brain develops, leading to issues with learning and memory later in life.

This peer-reviewed research confirms that these chemicals are not harmless. They are active substances that change how your body functions.