Yes, there are eco-friendly ways dispose of underwear and bras when you're done with them.
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What to Do with Old Underwear - Going Zero Waste
HanesBrands Partners With How2Recycle to Encourage Consumers to Join Company's Focus on Zero Waste
Canada's Underwear Recycling Program – Bota Undergarments
Donate Underwear for Textile Recycling
What To Do With Old Underwear: 13 Eco-Friendly Solutions – WAMA Underwear
What To Do With Old Underwear?
How to Sustainably Get Rid of Bras and Underwear
Bra recycling, Recycled Bras
Should we be recycling underwear? Yes, says this brand