{"hq_id":"hq-p-spe-000105","name":"Lead-Acid Battery (Sulfuric Acid, Lead, Hydrogen Gas During Charging)","category":{"primary":"specialty","secondary":"automotive","tags":["lead-acid battery","car battery","sulfuric acid","lead","hydrogen","charging","recycling"]},"product_tier":"SPE","overall_risk_level":"moderate_to_high","description":"Automotive lead-acid batteries containing lead plates in sulfuric acid electrolyte (30-40% H2SO4). Three hazards: sulfuric acid (corrosive burns), lead (neurotoxicant), and hydrogen gas (explosive during charging). Lead-acid batteries are the most recycled consumer product in the US (99% recycling rate). Battery acid on skin causes chemical burns within seconds. Hydrogen gas during charging: explosive in enclosed spaces — ventilate charging area. Jump-starting: connect positive first, negative last (ground to engine block, not battery terminal — prevents spark near hydrogen).","synthesis":{"derived_risk_level":"moderate","synthesis_confidence":0.729,"synthesis_method":"compound_composition","context_used":"human_adult","context_source":"product_users","exposure_modifier":0.654,"vulnerability_escalated":false,"escalation_reason":null,"compounds_resolved":2,"compounds_total":2,"synthesis_date":"2026-05-09","synthesis_version":"1.2.0","methodology_note":"exposure_modifier and adjusted_magnitude are computed from ALETHEIA-calibrated heuristics (route × duration × frequency multipliers, clamped to [0.5, 1.4]). Multipliers are directionally informed by EPA Exposure Factors Handbook (2011) and CalEPA OEHHA but are not regulatory consensus. See /api/methodology for full disclosure."},"hazard_summary":{"sensitive_populations":"DIY mechanics, anyone handling batteries","overall_risk":"moderate_to_high","primary_concerns":["Sulfuric acid: corrosive burns within seconds of skin contact","Hydrogen gas: explosive in enclosed charging area","Lead: neurotoxicant from terminal corrosion and handling","Improper jump-start: spark near hydrogen gas = explosion risk"],"exposure_routes":"Dermal (acid burns); inhalation (hydrogen gas, acid mist); lead handling"},"exposure":{"routes":["dermal","inhalation"],"contact_types":["skin_brief","inhalation"],"users":["adult"],"duration":"minutes","frequency":"rarely","scenarios":["Sulfuric acid splash during battery handling or jump-starting","Hydrogen gas explosion during charging in enclosed space","Lead exposure during battery terminal corrosion cleaning","Acid burn from cracked or leaking battery"],"notes":"99% recycling rate — highest of any consumer product. Auto parts stores (AutoZone, O'Reilly) accept used batteries for free. Core charge: $10-22 refunded when old battery returned. Sulfuric acid on skin: flush with water for 20+ minutes, seek medical attention. Jump-start procedure: positive (+) to positive first, negative (-) to engine block ground (NOT battery terminal) — prevents spark near hydrogen gas."},"consumer_guidance":{"usage_warning":"Wear safety goggles and chemical gloves when handling batteries. Ventilate charging area (hydrogen gas). Jump-start: positive-to-positive first, negative to engine ground (not battery terminal). If acid contacts skin: flush with water 20+ minutes, seek medical attention. Return used batteries to auto parts store (free, refund core charge).","safer_alternatives":["AGM (Absorbed Glass Mat) batteries — sealed, no free acid","Lithium starter batteries (emerging, no acid, lighter)","Professional battery service (eliminates DIY handling risk)","Auto parts store installation service (handles acid battery safely)"],"red_flags":[{"indicator":"Working without ventilation or respiratory protection","meaning":"Chemical exposure at hobby level can cause occupational-grade health effects.","action":"Use ventilation and PPE appropriate to the specific hazard."}],"green_flags":[{"indicator":"Using appropriate PPE and ventilation for the specific task","meaning":"Exposure controlled to safe levels.","verification":"Match PPE to specific hazard (N95 for dust, organic vapor for solvents, supplied air for isocyanate)."}],"what_to_ask":[{"question":"What are the specific chemical hazards of this hobby material?","why_it_matters":"Hobby exposures lack occupational protections but cause the same health effects.","good_answer":"SDS available, specific PPE identified, ventilation plan in place.","bad_answer":"No hazard awareness or PPE use."}],"alternatives":[{"name":"AGM","notes":"Absorbed Glass Mat) batteries — sealed, no free acid"},{"name":"Lithium starter batteries","notes":"emerging, no acid, lighter"},{"name":"Professional battery service","notes":"eliminates DIY handling risk"}]},"regulatory":{"applicable_regulations":[{"jurisdiction":"USA","regulation":"EPA Battery Recycling (RCRA Universal Waste)","citation":"40 CFR 273","requirements":"Lead-acid batteries classified as universal waste. Retailers and distributors must accept used batteries. 99% recycling rate.","compliance_status":null,"effective_date":null,"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":true,"disposal_guidance":"99% recycled. Return to any auto parts store for free. Core charge refunded. NEVER put in regular waste.","hazardous_waste":true,"expected_lifespan":"3-5_years"},"formulation":{"form":"varies","key_ingredients":[{"hq_id":"hq-c-ino-000051","name":"Sulfuric acid","role":"electrolyte","concentration_pct":"30-40"},{"hq_id":"hq-c-ino-000001","name":"Lead (Pb)","role":"plate_material","concentration_pct":"60 of battery weight"}],"certifications":[]},"materials":{"common":[],"concerning":[],"preferred":[]},"compound_composition":[{"hq_id":"hq-c-ino-000051","compound_name":null,"role":"electrolyte","typical_concentration":"30-40%"},{"hq_id":"hq-c-ino-000001","compound_name":null,"role":"plate_material","typical_concentration":"60% of battery weight"}],"identifiers":{"common_names":["lead-acid battery (sulfuric acid, lead, hydrogen gas during charging)"],"aliases":[],"manufacturer":null,"brands":[]},"brand_examples":[{"brand":"Dr. Dennis Gross","manufacturer":"Shiseido","market_position":"premium","notable":"LED skincare device brand"},{"brand":"Solawave","manufacturer":"Solawave","market_position":"premium","notable":"At-home LED therapy brand"},{"brand":"FOREO","manufacturer":"FOREO","market_position":"premium","notable":"Premium skincare tech devices"}],"brand_examples_disclaimer":"Representative branded products of this category. Concerning ingredients listed in materials.concerning[] apply to the category, not necessarily to every named brand. Specific formulations vary by SKU and may have changed since this record was written; consult the brand's current ingredient label before drawing brand-level conclusions.","sources":[{"type":"expert_curation","name":"ALETHEIA Safety Database","date":"2026-03-25"},{"type":"regulation","title":"EPA Battery Recycling (RCRA Universal Waste) (40 CFR 273)","jurisdiction":"USA","citation":"40 CFR 273","id":"src_4dc04939"},{"id":"niosh_h2so4_2019","type":"regulatory","title":"NIOSH Pocket Guide: Sulfuric Acid — IDLH 15 mg/m³; corrosive burns; battery acid; drain cleaner; dehydration mechanism; industrial production; PPE requirements (2019)","year":2019,"inherited_from_compound":"hq-c-ino-000051"},{"id":"iarc_strong_inorganic_acids_1992","type":"regulatory","title":"IARC Monograph Vol 54: Occupational Exposures to Mists and Vapours from Strong Inorganic Acids — Group 1 carcinogen (acid mist); laryngeal/lung cancer; H₂SO₄ occupational exposure; industrial settings (1992)","year":1992,"inherited_from_compound":"hq-c-ino-000051"},{"id":"src_001","type":"cdc","title":"CDC - Lead Poisoning Prevention","url":"https://www.cdc.gov/lead-prevention/","accessed":"2026-01-13","relevance":"Blood lead reference values, no safe level doctrine","inherited_from_compound":"hq-c-ino-000001"},{"id":"src_002","type":"who","title":"WHO - Lead Poisoning Fact Sheet","url":"https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health","year":2024,"accessed":"2026-01-13","relevance":"Global burden statistics, health effects","inherited_from_compound":"hq-c-ino-000001"}],"meta":{"schema_version":"4.0.0","last_updated":"2026-03-25","timestamp":"2026-05-14T01:22:51.224Z"}}