Pre-2003 CCA pressure-treated wood is the major residential source — bladder, lung, and skin cancer.

Substance-specific listings — these flags are for Arsenic alone, not for the broader family.
Inorganic arsenic is IARC Group 1 — confirmed to cause cancer in humans, with skin, bladder, and lung cancer the best-established endpoints. Chromated copper arsenate (CCA) pressure-treated wood was the standard residential deck and playset material until EPA voluntary phase-out in 2003. Pre-2003 decks, fences, and playground structures continue to leach arsenic into surrounding soil. Inorganic arsenic also occurs naturally in groundwater in much of the western U.S. and South Asia.
Severity scores specific to this substance, NOT the parent family average. Differences between siblings are real and meaningful.
Listed alphabetically — product categories where this specific substance appears.
We do not knowingly install anything containing Arsenic (As) and Compounds. Our specifications name the chemistry we refuse, every submittal is screened against it, and substitutions are rejected — which is how a toxin free home stays that way through construction.
If you want a house specified this way from the start, or an existing house assessed for what is already in it, that is the work we do. Earth Bound Homes builds in Atherton, Palo Alto, Redwood City and across the San Francisco Bay Area.