• Title slide on black: "Is epoxy resin toxic?" with the line "Liquid. Curing. Fully cured.", the subline "It depends on its state. And on what the label says." and the official exclamation mark hazard pictogram in red and white.
  • White slide "It depends on the state" with three numbered points: liquid epoxy resin can sensitize the skin, curing epoxy resin gives off irritating fumes, fully cured epoxy resin is considered chemically stable when mixed correctly.
  • Crimson slide "No skull. But not harmless either." with the official skull and crossbones pictogram GHS06 and the quote "Most commercially available epoxy resin systems don't carry a skull and crossbones; what counts is your product's label."
  • White slide with four official GHS hazard pictograms, exclamation mark, corrosion, health hazard, and environment, each with a short explanation and its H statement.
  • Black slide "Liquid, it's mainly a risk for your skin" noting that a single unprotected contact can be enough to trigger an allergy.
  • White slide "Most fumes are released right after mixing" with three fields for the liquid stage (most fumes), gel stage (still strong fumes), and tacky stage (still fumes) and the line "No smell anymore? That doesn't mean it's safe."
  • Crimson slide "At least 1 week out of living rooms and bedrooms" about final Shore hardness after 7 to 30 days, plus a note that children and pets stay out of the workspace.
  • Black closing slide "Your product's label decides, not this slide" with the question "Which hazard symbol is on your epoxy resin?"
  • White slide showing a mockup of the English edition of the book Safe Resin Art by Natalie Pikul, a woman with a respirator on the cover, with the note that the book is available in English, German, and Spanish. Link in bio.

Is epoxy resin toxic? It depends on its state: liquid, while it cures, or fully cured.

I'm Natalie Pikul, author of Safe Resin Art, and in the book I keep these three states apart.

Liquid: Many components of epoxy resin and hardener can sensitize your skin and be absorbed through it. Some hardeners are also corrosive. Sometimes a single unprotected contact is enough to trigger an allergy.

While it cures: As soon as epoxy resin and hardener react, they produce heat and fumes. Fumes peak right after mixing, while the epoxy resin is still liquid. There are still a lot of fumes in the gel stage, and in the tacky stage, the material keeps reacting and giving off fumes. The fumes are often invisible and can irritate your eyes, airways, and skin.

No smell anymore? That doesn't mean it's safe. The smell is often gone after one or two hours, but the substances stay active much longer.

Fully cured: Correctly mixed and fully cured, epoxy resin is considered chemically stable. But a full cure takes days to weeks, not hours. That's why you keep a freshly poured piece out of living rooms and bedrooms for at least a week, even if it already feels solid. Hardness or a lack of smell alone doesn't prove a full cure.

And what does "toxic" mean on the label? Under the EU CLP Regulation, the skull and crossbones (GHS06) stands only for acute toxicity, categories 1 to 3. Most commercially available epoxy resin systems don't carry a skull and crossbones; what counts is your product's label. Instead, you'll often see the exclamation mark, for example for skin sensitization, and on many hardeners the corrosion symbol. No skull doesn't mean harmless.

Children and pets stay out of your workspace, during curing too.

Source: Safe Resin Art, chapters 1, 2, 7, 9, and 10. I explain the hazard symbols based on CLP Regulation (EC) No 1272/2008. Your product's safety data sheet always comes first.

Bookmark this article for your next pour, so you know how long your piece needs to air out.

Check the label on your epoxy resin right now: Which hazard symbol is on it?

Safe Resin Art is available in English, German, and Spanish. Go to the book: Safe Resin Art.

Natalie Pikul

  • Hazard symbols
  • Epoxy resin safety

Go to the book: Safe Resin Art · Go to Epoxy Resin Knowledge

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