Wool Sports Performance Undergarments, ranked by PFAS safety

All 8 wool-based options in our sports performance undergarments database, graded Bad to Excellent and ranked safest first. None earn a buy-worthy grade yet, so start from the safest and check the swap suggestions.

Feetures Elite Light Cushion Tab Limited Edition Performance Socks

Feetures

Elite Light Cushion Tab Limited Edition Performance Socks

Merino wool blend, nylon, elastane

PFAS Grade65Good
Good

Lower concern. Merino wool socks unlikely to contain PFAS, but brand offers no transparency.

Risky category by default

Feetures High Performance Max Cushion Tab Socks

Feetures

High Performance Max Cushion Tab Socks

Merino wool blend, synthetic fibers

PFAS Grade65Good
Good

Lower concern socks; no PFAS-prone features identified.

Risky category by default

Smartwool Men's Run Targeted Cushion Mid Crew Socks

Smartwool

Men's Run Targeted Cushion Mid Crew Socks

Merino wool blend with synthetic nylon reinforcement

PFAS Grade65Good
Good

Lower concern. Natural fiber socks unlikely to contain PFAS.

Risky category by default

Smartwool Run Pattern Crew Socks 3-Pack

Smartwool

Run Pattern Crew Socks 3-Pack

Merino wool blend, no water repellent finish

PFAS Grade65Good
Good

Lower concern. Merino wool socks with no waterproof coating.

Risky category by default

Smartwool Women's Run Targeted Cushion Low Ankle Socks

Smartwool

Women's Run Targeted Cushion Low Ankle Socks

Merino wool blend, no specified water-repellent coating treatment

PFAS Grade65Good
Good

Lower concern. Merino wool socks without disclosed water repellent treatment.

Risky category by default

Smartwool Unisex Run Zero Cushion Crew Socks

Smartwool

Unisex Run Zero Cushion Crew Socks

Merino wool blend, no stated water-repellent treatment

PFAS Grade65Good
Good

Lower concern. Merino wool socks lack typical water-repellent coating coatings.

Risky category by default

Smartwool Men's Run Zero Cushion No Show Socks

Smartwool

Men's Run Zero Cushion No Show Socks

Merino wool blend, no reported water-resistant treatment

PFAS Grade65Good
Good

Lower concern. Merino wool socks unlikely to contain intentional PFAS.

Risky category by default

Smartwool Men's Run Cold Weather Targeted Cushion Crew Socks

Smartwool

Men's Run Cold Weather Targeted Cushion Crew Socks

Merino wool with water-repellent coating finish

PFAS Grade20Bad
Bad

Merino wool is PFAS-risk material; water-repellent coating finish raises concern.

Waterproof or stain-proof treatment

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