Is Linseed Oil Toxic?

In This Guide

Finding nontoxic wooden furniture can actually be just as challenging as finding a nontoxic sofa, even though you don’t have to worry about flame retardants. Choosing only solid wood pieces is a great start (lots of “wooden” furniture is really made of particle board or plywood which is glued together with formaldehyde-releasing adhesives), but the finishes can be another big problem.

One area of confusion for lots of folks is around linseed oil. Is this truly a nontoxic wood finish, or just Sneaky Stuff?

Here’s the deal with linseed:

Based on our research, we feel that pure, 100% linseed oil poses little, if any, toxic threat to human health, even though it does emit an odor as it dries. Material Data Safety Sheets (MSDS) on linseed oil tell us that it is non-toxic, and various other sources confirm this.]

Beware of “boiled linseed oil.”

The confusion around linseed oil arrives when with “boiled linseed oil,” which is what’s found in most stores/home-centers is confused with 100% linseed oil.

Basically, there are three types of linseed oil, two of which are non-toxic.

  1. Raw linseed oil is, in fact, flax seed oil. It takes a long time to dry but is entirely non-toxic.
  2. The polymerized version is true “boiled” linseed oil, sometimes called “stand oil”. Stand oil is generated by heating linseed oil near 300 °C for a few days in the complete absence of air. Under these conditions, a is highly viscous product results, which provides exceptionally uniform coatings that “dry” to more elastic coatings than linseed oil itself. It also dries much more quickly (although still more slowly than toxic, commonly-used polyurethanes.) This true boiled linseed oil is also non-toxic.
  3. The “boiled linseed oil” you can buy in most stores is actually mostly raw linseed oil, but with plasticizers, hardeners, and heavy metals added to make it act like true boiled oil, without the time and effort it takes to actually boil it; in other words, it’s cheap. Folks who are concerned about the toxicity of linseed oil are likely thinking of this type.

We’ve identified two sources for good linseed oil: Heritage Natural Finishes and Earthpaint.

Stay sane,

Author's Signature

Author's Signature

Maia, Founder & CEO

Note: This article contains affiliate links or sponsored content, which means that if you make a purchase, we may earn a commission. We only recommend products that meet our strict standards for non-toxicity and that we use (or want to use!) ourselves. Thank you so much for supporting the brands that make Good Stuff! 

Tags:Home Improvement & Yard Work

Leave a comment

17 comments

Shawn Chong

Great explanation, thank you so much! I will be buying flaxseed oil meant for ingestion, for wood finishing!

Chris

Thanks for the good info.

I’m now going to read the material safety data sheet before buying finishes

Esther

hi, does anyone know of a brand that IS nontoxic?

sean

what about Refined linseed oil?thx

Dell

The link supplied by Ryan is for Sunnyside RAW Linseed oil.
The Sunnyside BOILED Linseed OIl does indeed contain toxins.
https://www.sunnysidecorp.com/pdfs/SDS_87216.pdf

Browse Guides