{"hq_id":"hq-p-spe-000060","name":"Solar Panel (Cadmium Telluride Thin-Film and Crystalline Silicon)","category":{"primary":"specialty","secondary":"energy","tags":["solar panel","cadmium telluride","CdTe","lead solder","e-waste","photovoltaic"]},"product_tier":"SPE","overall_risk_level":"low","description":"Residential and commercial photovoltaic solar panels. Crystalline silicon panels (95% of market) contain lead solder (3-5g per panel) and silver. Thin-film CdTe panels (First Solar) contain cadmium telluride — cadmium is a toxic heavy metal. End-of-life disposal is the primary concern: 78 million tonnes of panel waste projected by 2050. Current recycling recovers glass and aluminum but often landfills the semiconductor layer.","synthesis":{"derived_risk_level":"low","synthesis_confidence":0.622,"synthesis_method":"compound_composition","context_used":"human_adult","context_source":"product_users","exposure_modifier":0.595,"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":"recycling workers, firefighters at panel fires","overall_risk":"low","primary_concerns":["End-of-life: lead and cadmium leaching from landfilled panels","Fire events volatilizing CdTe (cadmium fumes) — rare but severe","78 million tonnes of panel waste projected by 2050 with inadequate recycling"],"exposure_routes":"Normal use: none (sealed). End-of-life: soil/groundwater contamination from landfill."},"exposure":{"routes":["dermal"],"contact_types":["skin_brief"],"users":["adult","occupational"],"duration":"minutes","frequency":"rarely","scenarios":["Normal rooftop operation: zero exposure (sealed module)","Installation/handling: minimal dermal contact with frame","Fire damage releasing CdTe fumes (rare but severe)","End-of-life disposal: lead and cadmium leaching from landfilled panels"],"notes":"Normal solar panel operation presents zero chemical exposure to homeowners (sealed behind glass). Risk is concentrated in manufacturing, fire events (CdTe volatilization at 1,000C+), and end-of-life. First Solar operates the only dedicated CdTe panel recycling program (recovers 90%+ of cadmium). EU WEEE Directive requires panel take-back; US has no federal equivalent."},"consumer_guidance":{"usage_warning":"Solar panels present zero chemical exposure during normal rooftop operation. Ensure panels are recycled at end-of-life — do not landfill. Choose manufacturers with take-back/recycling programs.","safer_alternatives":["Crystalline silicon panels with lead-free solder (emerging)","First Solar CdTe panels (dedicated recycling program recovers cadmium)","Solar leasing programs that include manufacturer end-of-life recycling"],"red_flags":[{"indicator":"Unsubstantiated safety or environmental claims","meaning":"Product may not perform as marketed.","action":"Verify through independent testing or certification."}],"green_flags":[{"indicator":"Third-party certification","meaning":"Claims independently verified.","verification":"Check certification marks."}],"what_to_ask":[{"question":"What independent testing supports the claims?","why_it_matters":"Emerging products may lack long-term data.","good_answer":"Specific verifiable certification.","bad_answer":"No testing or self-certified."}],"alternatives":[{"name":"Crystalline silicon panels with lead-free solder","notes":"emerging"},{"name":"First Solar CdTe panels","notes":"dedicated recycling program recovers cadmium"},{"name":"Solar leasing programs that include manufacturer end-of-life recycling","notes":"Alternative"}]},"regulatory":{"applicable_regulations":[{"jurisdiction":"EU","regulation":"WEEE Directive (2012/19/EU)","citation":"Directive 2012/19/EU","requirements":"Solar panels classified as e-waste. Manufacturer take-back and recycling required.","compliance_status":null,"effective_date":"2014-02-14","enforcing_agency":"European Commission","penalties":null,"source_ref":null},{"jurisdiction":"USA -- Washington","regulation":"Washington State Solar Panel Stewardship Act","citation":"RCW 70A.510","requirements":"First US state to require solar panel manufacturer take-back program.","compliance_status":null,"effective_date":"2025-07-01","enforcing_agency":"WA DOE","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":"Solar panel e-waste recycling. First Solar: free take-back program for CdTe panels. EU: WEEE Directive mandates take-back. US: check state programs.","hazardous_waste":true,"expected_lifespan":"25-30_years"},"formulation":{"form":"varies","key_ingredients":[{"hq_id":"hq-c-ino-000094","name":"Cadmium telluride (CdTe) nanocrystals","role":"semiconductor_thin_film","concentration_pct":"1-3"},{"hq_id":"hq-c-ino-000001","name":"Lead (Pb)","role":"solder","concentration_pct":"trace"}],"certifications":[]},"materials":{"common":[],"concerning":[],"preferred":[]},"compound_composition":[{"hq_id":"hq-c-ino-000094","compound_name":null,"role":"semiconductor_thin_film","typical_concentration":"1-3%"},{"hq_id":"hq-c-ino-000001","compound_name":null,"role":"solder","typical_concentration":"trace"}],"identifiers":{"common_names":["solar panel (cadmium telluride thin-film and crystalline silicon)"],"aliases":[],"manufacturer":null,"brands":[]},"brand_examples":[{"brand":"3M","manufacturer":"3M","market_position":"mass_market","notable":"Safety and specialty product conglomerate"},{"brand":"Honeywell","manufacturer":"Honeywell","market_position":"mass_market","notable":"Safety equipment and technology"},{"brand":"DuPont","manufacturer":"DuPont","market_position":"professional","notable":"Chemical and safety products"}],"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":"WEEE Directive (2012/19/EU) (Directive 2012/19/EU)","jurisdiction":"EU","year":2014,"citation":"Directive 2012/19/EU","id":"src_88e0242e"},{"type":"regulation","title":"Washington State Solar Panel Stewardship Act (RCW 70A.510)","jurisdiction":"USA -- Washington","year":2025,"citation":"RCW 70A.510","id":"src_3835e78e"},{"id":"src_001","type":"database","title":"PubChem Compound CID 91501","url":"https://pubchem.ncbi.nlm.nih.gov/compound/91501","accessed":"2026-03-12","notes":"Chemical identity, properties, safety data","inherited_from_compound":"hq-c-ino-000094"},{"id":"src_002","type":"epa","title":"EPA CompTox Chemicals Dashboard — DTXSID0030950","url":"https://comptox.epa.gov/dashboard/chemical/details/DTXSID0030950","accessed":"2026-03-12","notes":"Hazard, exposure, and toxicity data","inherited_from_compound":"hq-c-ino-000094"}],"meta":{"schema_version":"4.0.0","last_updated":"2026-03-25","timestamp":"2026-05-14T01:24:07.032Z"}}