{"hq_id":"hq-p-out-000067","name":"Pressure-Treated Lumber for Decks (ACQ Copper Azole, CCA Legacy, Soil Leaching)","category":{"primary":"outdoor","secondary":"construction","tags":["pressure-treated","lumber","ACQ","CCA","copper azole","deck","arsenic","leaching"]},"product_tier":"OUT","overall_risk_level":"low","description":"CCA (chromated copper arsenate) banned for residential 2004, but millions of pre-2004 decks remain. Arsenic leaches to surface and transfers to hands. ACQ/CA-B replacement: copper-based, no arsenic — but copper leaches into soil and corrodes standard fasteners. Sealant every 1-2 years reduces CCA arsenic by 90%. NEVER burn CCA wood — ash is highly toxic.","synthesis":{"derived_risk_level":"extreme","synthesis_confidence":0.875,"synthesis_method":"compound_composition","context_used":"human_child","context_source":"product_users","exposure_modifier":1,"vulnerability_escalated":false,"escalation_reason":null,"compounds_resolved":1,"compounds_total":1,"synthesis_date":"2026-03-27","synthesis_version":"1.0.0"},"hazard_summary":{"sensitive_populations":"children (hand-to-mouth from CCA), aquatic ecosystems (copper leaching)","overall_risk":"low","primary_concerns":["Pre-2004 CCA decks: arsenic on surface","NEVER burn CCA wood (ash is extremely toxic)","ACQ copper leaching: phytotoxic, aquatic toxicity","ACQ corrodes standard metal fasteners"],"exposure_routes":"Dermal (hand contact with CCA); oral (children hand-to-mouth); environmental (copper leaching)"},"exposure":{"routes":["dermal","oral"],"contact_types":["skin_brief","oral_direct"],"users":["adult","child"],"duration":"hours","frequency":"weekly","scenarios":["Children touching CCA deck (arsenic hand-to-mouth)","Copper leaching from ACQ into soil (phytotoxic)","Sawing CCA wood: arsenic dust","Burning CCA wood: arsenic and chromium in ash (extremely toxic)"],"notes":"CCA surface arsenic: 60-200 ug/100cm2 on weathered wood. Sealant reduces transfer 90%. ACQ corrosion: requires stainless steel or hot-dipped galvanized fasteners. Alternatives: thermally modified wood, composite decking (Trex), naturally durable species (cedar, redwood, ipe). Hand washing after contact reduces exposure 90%+."},"consumer_guidance":{"usage_warning":"Pre-2004 deck? Seal every 1-2 years (90% arsenic reduction). Wash hands after touching old decks. NEVER burn pressure-treated wood. ACQ: use stainless steel fasteners. Don't plant food gardens against ACQ lumber.","safer_alternatives":["Penetrating stain on CCA wood every 1-2 years","Composite decking (no chemical preservatives)","Thermally modified wood (heat-treated, no chemicals)","Cedar, redwood, ipe (naturally durable)"]},"regulatory":{"applicable_regulations":[{"jurisdiction":"USA","regulation":"EPA CCA Phase-Out (2004)","citation":"EPA CCA Cancellation Order (2003)","requirements":"CCA voluntary phase-out for residential 12/31/2003. ACQ and CA-B: EPA-registered under FIFRA.","compliance_status":null,"effective_date":"2004-01-01","enforcing_agency":"EPA","penalties":null,"source_ref":null}],"certifications":[],"labeling":{"required_disclosures":[],"prop65_warning":{"required":null,"chemicals":[],"endpoint":null,"notes":null},"ghs_labeling":{"required":null,"signal_word":null,"pictograms":[],"hazard_statements":[],"notes":null},"hidden_ingredients":{"trade_secret_protected":null,"categories_hidden":[],"estimated_count":null,"known_concerns":null,"notes":null},"notes":null},"recalls":[],"regulatory_gap":null,"notes":null},"lifecycle":{"recyclable":false,"disposal_guidance":"CCA wood: hazardous waste. NEVER burn. ACQ: regular construction waste.","hazardous_waste":true,"expected_lifespan":"20-40_years"},"formulation":{"form":"varies","key_ingredients":[],"certifications":[]},"materials":{"common":[],"concerning":[],"preferred":[]},"compound_composition":[{"hq_id":"hq-c-ino-000002","compound_name":null,"role":"preserved_in_CCA_wood","typical_concentration":"0.4 lb/ft3 CCA retention"}],"identifiers":{"common_names":["pressure-treated lumber for decks (acq copper azole, cca legacy, soil leaching)"],"aliases":[],"manufacturer":null,"brands":[]},"brand_examples":[{"brand":"DAP","manufacturer":"DAP","market_position":"mass_market","notable":"Leading caulk and sealant brand"},{"brand":"GE Silicone","manufacturer":"Momentive","market_position":"mass_market","notable":"Silicone sealant brand"},{"brand":"Red Devil","manufacturer":"Red Devil","market_position":"mass_market","notable":"Budget caulk and sealant"}],"sources":[{"type":"expert_curation","name":"ALETHEIA Safety Database","date":"2026-03-25"},{"type":"regulation","title":"EPA CCA Phase-Out (2004) (EPA CCA Cancellation Order (2003))","jurisdiction":"USA","year":2004,"citation":"EPA CCA Cancellation Order (2003)","id":"src_17263aa9"},{"id":"iarc_100c","type":"regulatory","title":"IARC Monographs Volume 100C: Arsenic and Arsenic Compounds","year":2012,"inherited_from_compound":"hq-c-ino-000002"},{"id":"epa_arsenic_iris","type":"regulatory","title":"US EPA IRIS Assessment: Arsenic, Inorganic","year":1998,"inherited_from_compound":"hq-c-ino-000002"}],"meta":{"schema_version":"4.0.0","last_updated":"2026-03-25","timestamp":"2026-05-01T14:25:59.613Z"}}