{"hq_id":"hq-c-org-000602","name":"Diacetyl (butter flavor; 2,3-butanedione)","context":"human_adult","timestamp":"2026-08-28T02:50:52.082Z","risk_level":"low","risk_profile":{"magnitude":{"mean":0.2,"weightedMean":0.2,"std_dev":0,"confidence_interval_95":[0.2,0.2],"source_positions":[{"source":"HQ_DIRECT","year":2026,"value":0.2,"weight":0.35}]},"confidence":{"mean":0.5,"weightedMean":0.5,"std_dev":0,"confidence_interval_95":[0.5,0.5],"source_positions":[{"source":"HQ_DIRECT","year":2026,"value":0.5,"weight":0.35}]},"recency":{"mean":1,"weightedMean":1,"std_dev":0,"confidence_interval_95":[1,1],"source_positions":[{"source":"HQ_DIRECT","year":2026,"value":1,"weight":0.35}]},"methodology":{"mean":0.7,"weightedMean":0.7,"std_dev":0,"confidence_interval_95":[0.7,0.7],"source_positions":[{"source":"HQ_DIRECT","year":2026,"value":0.7,"weight":0.35}]},"specificity":{"mean":0.92,"weightedMean":0.92,"std_dev":0,"confidence_interval_95":[0.92,0.92],"source_positions":[{"source":"HQ_DIRECT","year":2026,"value":0.92,"weight":0.35}]},"consensus":{"exists":false,"strength":0,"disagreement_magnitude":0,"warning":"single_source_warning"}},"interpretation":{"summary":"Single source (HQ_DIRECT, 2026) indicates low risk.","confidence_note":"Evidence quality varies; interpretation requires caution.","context_note":null,"warning":"single_source_warning"},"sources":[{"id":"diacetyl_431-03-8_niosh_2016_popcorn_lung","type":"regulatory","title":"Diacetyl 2,3-Butanedione CAS 431-03-8 C4H6O2 Vicinal Diketone Butter Butterscotch Flavor; FDA GRAS Oral JECFA ADI Not Specified Ingestion; NIOSH 2016 Current Intelligence Bulletin #66 REL 0.02 ppm TWA Ceiling 0.06 ppm Inhalation; Occupational Bronchiolitis Obliterans Popcorn Lung Microwave Popcorn Manufacturing 2000-2016 NIOSH HHE 25-270 ppm Mixing Spraying; Lactococcus Lactis Leuconostoc Alpha-Acetolactate Natural Butter Beer Wine Fermentation Metabolite; Parmet 2007 NEJM Consumer Case 2 Bags/Day 10 Years Microwave Poorly Ventilated; Industry Reformulation Acetoin 2,3-Pentanedione CAS 600-14-6 Similar NIOSH Toxicity 2014; Farsalinos 2015 IJERPH 74.2% Sweet Flavored E-Cigarettes Diacetyl 239 ug/Puff; Allen 2016 EHP Harvard 39/51 Diacetyl 23/51 2,3-Pentanedione; Arginine Diketone Protein Reactivity Bronchiolar Fibrosis Constrictive Obliterative Mechanism; Route-Dependent Risk: Oral GRAS vs Inhalation REL 0.02 ppm","year":2016,"url":"https://www.cdc.gov/niosh/docs/2016-111/"}],"sources_scope":"record","warnings":["unmapped_classification:IARC:not evaluated by iarc for carcinogenicity — diacet","unmapped_classification:EPA CTX / Genetox:genotoxicity: positive (ames: positive, 5 positive","unmapped_classification:EPA CTX / Genetox:genotoxicity: positive (ames: positive, 5 positive","single_source_warning"],"meta":{"synthesis_version":"1.1.0","config_version":"1.1.0","n_sources":1,"db_version":46,"warnings":["unmapped_classification:IARC:not evaluated by iarc for carcinogenicity — diacet","unmapped_classification:EPA CTX / Genetox:genotoxicity: positive (ames: positive, 5 positive","unmapped_classification:EPA CTX / Genetox:genotoxicity: positive (ames: positive, 5 positive"]},"schema":"synthesis","_notice":"ALETHEIA output is reference data, not professional advice. Not a substitute for primary agency sources or qualified professionals. See https://aletheia.holisticquality.io/disclaimer.","_disclaimer_url":"https://aletheia.holisticquality.io/disclaimer","available_contexts":["human_adult","human_child","exposure_inhalation","aquatic_life","human_teen","human_elderly","human_infant","human_pregnant"]}