Lyocell and TENCEL: the solvent spun plant fibre

Why it matters for your body

Lyocell is a regenerated cellulose fibre. The pulp, usually from wood, is dissolved and spun into a new filament. European fibre law gives it its own name, separate from viscose and from modal: the pulp is dissolved in an organic solvent and spun without the chemical rebuild that viscose uses (EU textile fibre names, Annex I). US labels use the same generic word, lyocell (16 CFR 303.7).

TENCEL is a Lenzing brand, not a fibre class. TENCEL Lyocell is this fibre. The solvent is NMMO (N-methylmorpholine N-oxide), which the mill recovers and reuses in a closed loop, with no carbon disulfide step (Lenzing, on TENCEL Lyocell). That is the maker’s account of its own mill. It matches the legal split between lyocell and viscose, which is the part a shopper can check without taking the brand’s word for the whole environmental story (Lenzing, fibre technologies).

On skin, lyocell is soft and handles moisture well, which is why it shows up in tees, underwear, and bedding. It is still a fibre that was rebuilt in a mill. Dye and finish sit on top, the same as they do on cotton.

Have a soft tee nearby? Check a product.

The public read: Better choice

We name a public verdict and leave the internal math unpublished. The high level method is on the scoring method.

Lyocell, including TENCEL Lyocell: Better choice.

Better choice means this process is the one we prefer among regenerated cellulose fibres for clothes that touch skin. It is not a claim that the shirt is chemically blank. It is the fibre read, based on how the filament is made rather than on a wood story alone.

TENCEL is not one fibre

A hangtag that only says TENCEL is unfinished. TENCEL Modal is modal, a modified viscose, and that page has its own read. LENZING ECOVERO is viscose. It is not TENCEL, and it is not lyocell. Commodity viscose and rayon, including most bamboo viscose, are a different process again.

If the label says lyocell, or TENCEL Lyocell, you are on this page. If it says modal, viscose, rayon, or ECOVERO, you are not, even when the advertisement talks about trees.

What a badge does not do

OEKO-TEX Standard 100 tests the article for harmful substances and sets limits by skin contact (OEKO-TEX Standard 100). GOTS is a processing standard for certified organic natural fibres (GOTS). Lyocell is regenerated cellulose, so a GOTS mark on a blend is about the organic fibre in that blend, not a new status for the lyocell. Neither badge raises a TFD health number.

Elastane next to lyocell is still elastane. The lyocell line can be Better choice while the stretch line is Prefer less.

What to look for on the label

• Lyocell, or TENCEL Lyocell: this fibre. Public read: Better choice.
• TENCEL with no second word: ask whether it is lyocell or modal.
• TENCEL Modal: modal, not this page.
• ECOVERO, viscose, or rayon: not lyocell.
• Elastane or polyester in the same composition: read those lines separately.
• OEKO-TEX or GOTS: process and limit checks, not a health number raise.

How to read a clothing label is the one minute version of the house name problem.

A 60-second table

Scan a piece you already own

Paste a product URL or type the composition into Toxic Fashion Detector. A tee or a set of sheets you sleep in is the useful case. For cleaner brand defaults, browse the brand directory.