Hylea
Base Layers
Form-fitting underlayers worn for temperature regulation during outdoor activities. Made from synthetic fabrics or merino wool.
Why It Matters
Base layers are worn directly against skin during sweating, maximizing absorption potential. Disperse dyes in synthetics can cause allergic reactions. Often treated with antimicrobial chemicals. NPE residues may remain from manufacturing.
Chemicals of Concern in This Product
Disperse Dyes
A class of dyes used primarily for coloring synthetic fabrics like polyester, nylon, and...
Formaldehyde and Formaldehyde Releasers
A colorless gas used as a preservative, disinfectant, and textile finishing agent. In clothing,...
Nonylphenol Ethoxylates (NPEs)
A class of surfactants widely used in textile manufacturing for washing, dyeing, and finishing...
Antimicrobial Additives
Chemicals added to products to kill or inhibit microorganisms. Includes silver nanoparticles,...
PFAS (Per- and Polyfluoroalkyl Substances)
A large group of synthetic chemicals known as 'forever chemicals' because they don't...
Microplastics
Tiny plastic particles less than 5mm in size, including microbeads in products and fragments...
Ingredient Red Flags
Watch for these on ingredient labels:
- Antimicrobial or odor-resistant claims on synthetics
- Synthetic fabrics causing skin irritation
- Silver or zinc treatments
- No certifications
What to Look For
- ✓Merino wool (naturally antimicrobial)
- ✓No antimicrobial treatments
- ✓PFAS-free moisture wicking
Finding Safer Options
Merino wool base layers from brands like Icebreaker or Smartwool - wool is naturally odor-resistant without chemical treatments. Organic cotton for lower-intensity activities.
Certifications to Look For
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