The Fitted Wool Carpet Without the Hidden Plastic
“Pure wool pile, glued to polypropylene and styrene-butadiene rubber. Coated in permethrin. Laid over polyurethane foam. Half the product has never been declared.”
The Problem
The air in the bed-height breathing zone carries 528 microplastic particles per cubic metre. Ninety-four percent are under 10 µm — fine enough to reach the distal airway. The lung retires wool. It does not retire polypropylene, polyester, or polyethylene. A 2022 study found those fibres in eleven of thirteen human lung samples, lodged in tissue, not clearing.
The floor is the largest textile surface in the room. Every step resuspends what has settled there and what the flooring itself is shedding. A carpet is not inert. It is a reservoir, and it is a source.
Wool carpet is sold on the face — the fibre you see. The half you don't see is plastic. Under the pile sits a polypropylene primary backing, spun to mimic jute. Under that, a styrene-butadiene rubber secondary backing that sheds its own 1–10 µm fibres as it ages. Under that, a polyurethane foam underlay made from recycled mattress offcuts, crumbling by year ten. The pile is coated in permethrin — a pyrethroid pesticide, industry default, never named on the label. Sometimes a fluorochemical finish banned in children's clothing, still legal in your hallway.
The Gap
We called the UK mills. "One hundred percent pure new wool" — on the face. Secondary backing: trade secret. Moth treatment: "standard industry practice." Dye chemistry: not on the spec sheet. Every layer, every adhesive, every treatment exists in the industrial supply chain. Nobody assembles them all and declares them.
What Should Exist
A fitted wool carpet where every layer is named, and every layer is honest.
- Woven construction — Wilton or Brussels weave, pile and ground integrated on the loom. Not tufted and glued.
- Jute primary backing, natural latex or no secondary — GOLS-certified natural latex if bonded; SBR, PVC, and acrylic latex are out.
- Untreated pile, or named natural moth treatment — cedar or lavender, volume and method disclosed. No permethrin. No pyrethroid of any class.
- No fluorochemical finish, no silicone topcoat, no ammonium anti-static — wool already resists stain and flame.
- Wool felt or rubberised hair underlay — UK-made, sold paired. Polyurethane foam is out.
- Declared provenance and dye chemistry — country of origin minimum, farm preferred. Acid dyes or undyed. No chromium.
The Honest Position
This is a premium product. Woven wool with wool-felt underlay, every layer declared, will not meet the price of tufted polypropylene. Moths eat stored wool, not actively trodden wool — a carpet you walk on daily does not need a pesticide bath. This is for the room you sleep in, not a five-year rental refit. If you want a blend with a chemical warranty, you already have that option.
The Investigation: The Invisible Breath — the microplastic load in the air where you sleep, and where it comes from.