{"hq_id":"hq-p-hom-000031","name":"Mothballs and solid deodorizer blocks","category":{"primary":"household","secondary":"moth control / pest deterrent / closet and storage deodorizers","tags":["mothball safety","naphthalene mothballs","paradichlorobenzene mothballs","1,4-DCB moth control","mothball poisoning children","naphthalene IARC 2B","moth ball G6PD hemolysis","paradichlorobenzene IARC","toilet bowl deodorizer chemicals","camphor mothballs","mothball child ingestion","naphthalene storage vapor","cedar alternative mothballs","paradichlorobenzene VOC","mothball hemolytic anemia"]},"product_tier":"HOM","overall_risk_level":"high","description":"Conventional mothballs and solid moth-control/storage deodorizer products sold in the United States contain one of three active ingredients: naphthalene, paradichlorobenzene (1,4-dichlorobenzene, 1,4-DCB), or camphor. All three are volatile solid aromatic compounds that sublimate at room temperature, releasing vapors that repel clothes moths (Tineola bisselliella) and carpet beetles from stored textiles. These products are acutely hazardous in ways that are frequently underestimated by consumers, particularly regarding pediatric poisoning risk and specific genetic vulnerability. Naphthalene and 1,4-dichlorobenzene are both classified as IARC Group 2B possible human carcinogens. Naphthalene triggers hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency — a genetic variant found in approximately 400 million people worldwide, with highest prevalence in African, Mediterranean, and Southeast Asian populations. G6PD deficiency is X-linked, making males disproportionately affected. Naphthalene exposure in G6PD-deficient individuals can cause acute hemolytic crisis with rapid red blood cell destruction, anemia, jaundice, and in severe cases, acute kidney failure from hemoglobin-derived pigments damaging renal tubules. Infants with undiagnosed G6PD deficiency are particularly vulnerable — neonatal hemolytic crisis has been documented from closet naphthalene vapor exposure. Both naphthalene and 1,4-DCB mothballs come in the form of white or cream-colored spheres or cylinders that resemble candy or food items, creating substantial pediatric ingestion risk. Hundreds of cases of childhood mothball ingestion are reported to Poison Control annually. Camphor, the third active ingredient, is rapidly absorbed through the GI tract and skin and causes seizures in infants and young children at doses as low as 1 gram — one or two camphor balls. Paradichlorobenzene (1,4-DCB) is also the active ingredient in widely used toilet bowl deodorizer blocks, creating an additional exposure pathway distinct from the closet/storage mothball context.","synthesis":{"derived_risk_level":"moderate_to_high","synthesis_confidence":0.738,"synthesis_method":"compound_composition","context_used":"human_infant","context_source":"product_users","exposure_modifier":1.2,"vulnerability_escalated":true,"escalation_reason":"Infant exposure group","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":"children","overall_risk":"high","primary_concerns":["Carcinogenicity concern (high): Naphthalene, p-Dichlorobenzene Naphthalene's most acute danger is selective hemolytic toxicity in G6PD-deficient individuals. 1,4-DCB is not only a mothball ingredient — it is the active ingredient in the vast majority of toilet bowl deodorizer blocks sold in the US, as well as in some urinal cakes and room deodorizers."],"exposure_routes":"inhalation, ingestion"},"exposure":{"routes":["dermal"],"contact_types":["inhalation","ingestion"],"users":["adult","infant","child","toddler"],"duration":"chronic (inhalation during storage season); acute (ingestion — pediatric poisoning)","frequency":"seasonal (moth control); continuous (toilet bowl deodorizers)","scenarios":["Incidental mouthing or hand-to-mouth transfer by children"],"notes":"Mothball inhalation exposure occurs when stored clothing is placed in an enclosed space (closet, trunk, cedar chest) with mothballs — vapor concentrations in the enclosed space can be very high. Exposure continues when the space is opened and when treated clothing is removed and worn (naphthalene/1,4-DCB impregnates fabric and slowly offgasses). Pediatric ingestion risk: mothballs closely resemble candy or food — small, white, round — and have been ingested by young children in documented pediatric poisoning cases. Toilet bowl deodorizer block exposure is continuous inhalation in bathroom environments."},"consumer_guidance":{"red_flags":[{"indicator":"Household member with known or suspected G6PD deficiency in family with naphthalene mothball use; African, Mediterranean, or Southeast Asian family ancestry with unscreened infants","meaning":"G6PD deficiency is common in these populations and substantially increases the risk of hemolytic crisis from naphthalene exposure. G6PD screening at birth (newborn screening) is performed in some US states but not universally. Unscreened infants of unknown G6PD status from high-prevalence ancestry groups face serious risk from naphthalene vapor exposure in enclosed spaces.","action":"Eliminate naphthalene mothballs from any household where G6PD deficiency is possible. Use cedar or lavender alternatives. If G6PD status is unknown in an infant from a high-risk ancestry group, discuss screening with the pediatrician. Naphthalene exposure in a G6PD-deficient infant can cause hemolytic crisis without direct ingestion — vapor exposure is sufficient."},{"indicator":"Mothballs stored anywhere accessible to children under 6; mothballs left in open containers or loose in drawers accessible to young children","meaning":"Mothballs are a documented pediatric ingestion hazard — they resemble candies or mints and have no child-resistant packaging requirement in the US. Even a single naphthalene or 1,4-DCB mothball ingested by a young child causes toxidrome: nausea, vomiting, hemolytic anemia (naphthalene), and CNS effects. Camphor mothball ingestion causes seizures within 1 hour at doses of 1 gram.","action":"Store mothballs and all pesticide products in locked cabinets inaccessible to children. Contact Poison Control immediately (1-800-222-1222) for any suspected mothball ingestion by a child. Do not induce vomiting — follow Poison Control guidance. Cedar and lavender alternatives eliminate this ingestion risk entirely."}],"green_flags":[{"indicator":"Cedar wood blocks, chips, or cedar-oil sachets used for moth deterrence; lavender sachets; vacuum-sealed storage bags for long-term textile storage; regular inspection for moths","meaning":"Cedar and lavender provide effective moth deterrence without IARC Group 2B carcinogens, hemolytic toxicants, or pediatric seizure risk. These alternatives are safe for use in households with children and G6PD-deficient individuals. Airtight storage physically prevents moth access — the most reliable long-term protection.","verification":"Eastern red cedar (Juniperus virginiana) products marketed specifically for moth protection are the most common form. Cedar oil content diminishes over time — lightly sand cedar blocks annually and apply cedar oil to refresh. Lavender sachets should be replaced annually as the volatile oil evaporates."}],"what_to_ask":[{"question":"What is the active ingredient in this moth control product — naphthalene, paradichlorobenzene, or camphor? Are there children or individuals with G6PD deficiency in this household? Is there an alternative to chemical mothballs for my textile storage needs?","why_it_matters":"Active ingredient determines the specific hazard profile. Naphthalene poses hemolytic risk to G6PD-deficient individuals — a genetic variant affecting hundreds of millions globally. Camphor poses acute seizure risk to infants and young children. Paradichlorobenzene is a probable carcinogen in ubiquitous use. Cedar and lavender provide effective alternatives without these hazards.","good_answer":"Cedar, lavender, or other non-chemical alternatives recommended; if chemical product must be used, explicit labeling of G6PD hemolysis risk for naphthalene with instructions to avoid use in households with G6PD deficiency or unscreened infants; child-resistant packaging; storage-only instructions (not to be used in lived spaces).","bad_answer":"No ingredient labeling visible; product displayed or stored within reach of children; no G6PD hemolysis warning on naphthalene products; no child safety warnings on camphor-containing products; products placed in open containers accessible to children."}],"alternatives":[{"name":"Cedar chips or blocks","notes":"Natural repellent with lower toxicity and pleasant scent"},{"name":"Lavender sachets or dried herbs","notes":"Non-toxic natural deodorizers safe for all spaces"},{"name":"Activated charcoal odor absorbers","notes":"Safer alternative without harmful chemical vapors"}],"notes":null},"regulatory":{"applicable_regulations":[{"jurisdiction":"US","regulation":"EPA — Pesticide Registration: Naphthalene and Paradichlorobenzene as active ingredients in moth control products (registered pesticides under FIFRA)","citation":null,"requirements":"Both naphthalene and paradichlorobenzene are registered as pesticide active ingredients under FIFRA for use in moth control products. Registration requires efficacy data and hazard labeling. EPA's pesticide registration for these ingredients requires labels to include: storage directions (use only in closed containers, do not let children handle), first aid instructions, and hazard warnings. However, the hazard warnings do not always prominently feature the G6PD hemolysis risk for naphthalene or the IARC carcinogenicity classifications for either compound.","compliance_status":null,"effective_date":null,"enforcing_agency":null,"penalties":null,"source_ref":"src_001"}],"certifications":[{"name":"CPSC General Safety","issuer":"CPSC","standard":"Consumer Product Safety Act","scope":"General consumer product safety requirements"}],"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":null,"disposal_guidance":"Varies by material; check local recycling guidelines","hazardous_waste":false,"expected_lifespan":"1-3_years"},"formulation":{"form":"composite_material","key_ingredients":[{"hq_id":null,"name":"Primary component","role":"base_material","concentration_pct":"70-80"},{"hq_id":null,"name":"Secondary component","role":"additive","concentration_pct":"10-20"},{"hq_id":null,"name":"Filler or coating","role":"filler","concentration_pct":"5-10"}],"certifications":[]},"materials":{"common":[{"material_id":null,"material_name":"Naphthalene","component":"active moth-repellent volatile compound in naphthalene mothballs","prevalence":"common (one of two dominant mothball active ingredients in US market)","notes":"Naphthalene: IARC Group 2B possible human carcinogen. CAS 91-20-3. Volatile PAH (polycyclic aromatic hydrocarbon); sublimation point 80°C but significant vapor pressure at room temperature. Naphthalene is the volatile agent responsible for the characteristic 'mothball smell.' It is a potent hemolytic agent in G6PD-deficient individuals — RBC oxidative stress from naphthalene metabolites (alpha-naphthol, naphthoquinone) overwhelms the antioxidant defense capacity of G6PD-deficient red blood cells, causing acute hemolysis. Also neurotoxic in infants even without G6PD deficiency. EPA IRIS: naphthalene is a probable human carcinogen based on nasal cancer in rats at high inhalation exposures. Occupational NIOSH REL: 10 ppm (8-hour TWA) — closed storage spaces with mothballs can dramatically exceed this.","_note_crossref_fix":"Was hq-c-org-000096 — compound ref moved to compound_composition"},{"material_id":null,"material_name":"p-Dichlorobenzene (1,4-dichlorobenzene, paradichlorobenzene)","component":"active ingredient in 1,4-DCB mothballs and toilet bowl deodorizer blocks","prevalence":"common (toilet bowl deodorizer blocks ubiquitous; mothballs common)","notes":"1,4-Dichlorobenzene: IARC Group 2B possible human carcinogen. CAS 106-46-7. Chlorinated volatile aromatic; somewhat less objectionable odor than naphthalene, which drove market share shift from naphthalene to 1,4-DCB mothballs in the late 20th century. 1,4-DCB is hepatotoxic and nephrotoxic at high doses. EPA has a drinking water Maximum Contaminant Level Goal (MCLG) of 0.075 mg/L and drinking water MCL of 0.075 mg/L for 1,4-DCB. Ubiquitous in indoor air environments where toilet bowl deodorizer blocks are used — studies have found 1,4-DCB in blood of the vast majority of US adults tested (NHANES), attributed primarily to consumer product exposure from toilet bowl blocks and air fresheners. Like naphthalene, it comes as white/cream spheres indistinguishable in appearance from candy.","_note_crossref_fix":"Was hq-c-org-000413 — compound ref moved to compound_composition"},{"material_id":null,"material_name":"Camphor","component":"active ingredient in camphor mothballs and moth-repellent products","prevalence":"less common (smaller market share than naphthalene or 1,4-DCB in US)","notes":"Camphor (CAS 76-22-2): natural terpene compound from camphor laurel; also synthetically produced. Long history as medicinal ingredient (Vicks VapoRub contains camphor) and as moth repellent. Camphor is readily absorbed through the GI tract, skin, and mucous membranes. Toxic dose in infants: as low as 750mg–1g (one or two camphor balls). Toxidrome: rapidly progressing CNS stimulation — agitation, tremor, convulsive seizures — within minutes to 1 hour of ingestion. Camphor-induced seizures in infants have been documented from: (1) direct ingestion, (2) skin application of camphor-containing products to broken skin, (3) excessive use of camphor-containing vapor rubs on very young infants. No antidote; treatment is supportive (seizure management).","_note_crossref_fix":"Was hq-c-org-000095 — compound ref moved to compound_composition"}],"concerning":[{"material_id":null,"material_name":"Naphthalene — hemolytic crisis in G6PD-deficient individuals; pediatric neurotoxicity","concern":"Naphthalene's most acute danger is selective hemolytic toxicity in G6PD-deficient individuals. G6PD deficiency affects approximately 10–14% of African-American males and significant proportions of Mediterranean, Middle Eastern, and Southeast Asian populations — making this a population-level, not purely individual, risk. Mothers carrying G6PD-deficient infants have been documented to cause neonatal hemolytic crisis through naphthalene mothball use in the home (vapor exposure to the infant). Acute hemolytic crisis from naphthalene: rapid fall in hemoglobin, jaundice, dark urine (hemoglobinuria), weakness — potentially progressing to severe anemia requiring transfusion and acute kidney injury from hemoglobin pigment deposition in renal tubules. For G6PD-normal individuals, naphthalene is still a probable carcinogen (IARC 2B) with evidence for nasal cancer and potentially liver cancer at chronic high exposures.","compounds_of_concern":["hq-c-org-000096"],"source_refs":["src_001","src_002"],"_note_crossref_fix":"Was hq-c-org-000096 — compound ref moved to compound_composition"},{"material_id":null,"material_name":"1,4-Dichlorobenzene — IARC 2B carcinogen in ubiquitous toilet bowl deodorizers; VOC indoor air burden","concern":"1,4-DCB is not only a mothball ingredient — it is the active ingredient in the vast majority of toilet bowl deodorizer blocks sold in the US, as well as in some urinal cakes and room deodorizers. CDC NHANES data has found 1,4-DCB in the blood of more than 96% of the US population sampled — a ubiquity level indicating near-universal exposure through consumer product use. The primary exposure route is inhalation of vapors in bathrooms and spaces where these products are used. Animal studies show 1,4-DCB is carcinogenic (kidney tumors in rats, liver tumors in mice); IARC Group 2B for humans. Liver and kidney toxicity at high doses. Indoor air 1,4-DCB concentrations in households using toilet bowl deodorizers can exceed EPA cancer risk benchmarks at chronic exposure.","compounds_of_concern":["hq-c-org-000413"],"source_refs":["src_001","src_003"],"_note_crossref_fix":"Was hq-c-org-000413 — compound ref moved to compound_composition"}],"preferred":[{"material_id":null,"material_name":"Cedar blocks and cedar oil sachets; lavender sachets; sealed airtight storage containers; proper textile cleaning before storage; regular inspection","why_preferred":"Cedar wood (eastern red cedar, Juniperus virginiana) contains terpene oils that repel clothes moths effectively without carcinogenic volatile compounds. Cedar blocks, cedar chips, cedar sachets, and cedar oil-impregnated products are effective at deterring moths from stored clothing. Cedar oil effectiveness diminishes as the aromatic oils evaporate — cedar blocks should be lightly sanded or re-treated with cedar oil annually to maintain effectiveness. Lavender sachets similarly repel moths with a pleasant scent and no carcinogenic/hemolytic compounds. Sealed airtight storage (vacuum bags, sealed plastic bins) physically prevents moth access without requiring any chemical agent — the most reliable method for long-term textile storage. Properly dry-cleaned or washed textiles (to remove any existing moth eggs) stored in sealed containers are protected without chemical exposure.","tradeoffs":"Cedar and lavender are effective deterrents but may be less reliably lethal to existing moth eggs and larvae than naphthalene or 1,4-DCB. For textiles with existing moth infestation (visible moth holes, larvae, or eggs), chemical treatment or professional dry cleaning followed by sealed storage is more reliable. Cedar blocks require maintenance (sanding, re-oiling) to remain effective."}]},"compound_composition":[{"hq_id":"hq-c-org-000096","compound_name":"Naphthalene","role":"compound_of_concern","typical_concentration":null},{"hq_id":"hq-c-org-000413","compound_name":"p-Dichlorobenzene (1,4-dichlorobenzene)","role":"compound_of_concern","typical_concentration":null}],"identifiers":{"common_names":["mothballs and solid deodorizer blocks","mothballs","solid deodorizer blocks","mothballs and solid deodorizer block"],"aliases":[],"manufacturer":null,"brands":[]},"brand_examples":[{"brand":"Generic Mass-Market Brand A","manufacturer":"Consumer Products Corporation","market_position":"mass_market","notable":"Widely available mass-market option"},{"brand":"Generic Mass-Market Brand B","manufacturer":"Consumer Goods Ltd","market_position":"mass_market","notable":"Popular budget alternative"},{"brand":"Premium Brand A","manufacturer":"Premium Consumer Inc","market_position":"premium","notable":"Upscale premium positioning"},{"brand":"Professional Brand","manufacturer":"Professional Products Co","market_position":"professional","notable":"Professional/salon-grade option"},{"brand":"Specialty Eco-Brand","manufacturer":"Natural Products Ltd","market_position":"premium","notable":"Sustainable/natural product line"}],"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":[{"id":"src_001","type":"regulatory","title":"EPA — Naphthalene and Paradichlorobenzene: Registered Pesticide Fact Sheets","url":"https://www.epa.gov/pesticides","accessed":"2026-03-08","year":2020,"notes":"EPA FIFRA registration data for naphthalene and paradichlorobenzene as moth control active ingredients; hazard characterization; label requirements; IARC Group 2B classification for both; EPA IRIS carcinogenicity assessment for naphthalene"},{"id":"src_002","type":"journal","title":"Luzzatto L et al. — 'Glucose-6-phosphate dehydrogenase deficiency.' Hematology/Oncology Clinics of North America (2010)","url":"https://doi.org/10.1016/j.hoc.2010.01.005","accessed":"2026-03-08","year":2010,"notes":"Comprehensive review of G6PD deficiency; global prevalence (400 million affected); X-linked inheritance; hemolytic crisis triggers including naphthalene; neonatal hemolytic jaundice; clinical management; implications for exposures including naphthalene mothball vapor; basis for G6PD-naphthalene risk documentation"},{"id":"src_003","type":"government_report","title":"CDC NHANES — Exposure to environmental chemicals: 1,4-dichlorobenzene serum data","url":"https://www.cdc.gov/exposurereport/","accessed":"2026-03-08","year":2022,"notes":"National biomonitoring data showing >96% of US population has detectable 1,4-DCB in blood; attributed to consumer product exposure (toilet bowl blocks, air fresheners, mothballs); basis for near-universal population exposure characterization; concentration trends over time"}],"meta":{"schema_version":"4.0.0","last_updated":"2026-03-25","timestamp":"2026-05-14T01:27:06.683Z"}}