Outdoor & Yard / Products / Pressure-Treated Lumber Deck

Pressure-Treated Lumber Deck — outdoor safety profile

High risk

Pressure-treated lumber used for outdoor decks, fences, and playground structures.

What is this product?

Pressure-treated lumber used for outdoor decks, fences, and playground structures. Pre-2004 treatment was CCA (chromated copper arsenate) containing arsenic and chromium VI. Post-2004 residential treatment is ACQ (alkaline copper quaternary) or CA-B (copper azole). CCA-treated wood remains in millions of existing structures. ACQ uses high copper concentrations that leach into soil.

What's in it

Click any compound name for its full safety profile, regulatory consensus, and exposure data.

Preservative Current

Who's most at risk

  • Children — Developing endocrine and neurological systems, higher exposure per body weight

Red flags — when to walk away

  • Product used in enclosed or poorly ventilated spaceChemical exposure concentrations increase dramatically in enclosed spaces.

Green flags — what to look for

  • Third-party safety certification visible on packagingProduct has been independently tested to applicable safety standards.

Safer alternatives

  • Composite decking — Trex, TimberTech) — no chemical leaching
  • Naturally rot-resistant wood — cedar, redwood, black locust
  • Thermally modified wood — heat treatment, no chemicals

Frequently asked questions

Who should be careful with Pressure-Treated Lumber Deck?

Vulnerable populations identified for this product type: children.

Are there safer alternatives to Pressure-Treated Lumber Deck?

Yes — consider: Composite decking; Naturally rot-resistant wood; Thermally modified wood. See the Safer alternatives section above for details.

Look up Pressure-Treated Lumber Deck in the outdoor app

Search by ingredient, browse by category, or compare to alternatives in the live app.

Open in outdoor View raw API data

Reference data, not professional advice. Aggregates publicly available regulatory and scientific information. Why we built ALETHEIA →