--- topic: "Household Chemicals" title: "What You're Really Breathing from Candles and Air Fresheners" order: 2 description: "How paraffin candles, plug-in fresheners, and synthetic fragrance pollute your indoor air" question: "Are scented candles and air fresheners bad for your health?" answer: "Air fresheners may release benzene and formaldehyde, and many paraffin candles in a small room add combustion byproducts, though harm at typical use is unproven." actions: - "Open windows on opposite sides of your home for five minutes; ventilation is the simplest air freshener." - "If you burn candles, choose 100% beeswax or soy with cotton or wood wicks, and avoid burning several in a small, poorly ventilated room." - "Skip plug-in and spray fresheners; if you want scent, use an essential-oil diffuser sparingly, especially around pets and children." cautions: - "'Fragrance' or 'parfum' on a label can hide dozens of undisclosed chemicals, including phthalates linked to reduced lung function [2]." - "Essential oils are potent and not risk-free; use them sparingly, especially around pets and children." - "Not a substitute for medical care if headaches, congestion or breathing symptoms persist." confidence: 2 confidenceNote: "A school air-quality review, one observational phthalate-lung study and one lab study of candle emissions; no air-freshener emission measurements and no trials." evidenceSummary: rctCount: 0 observationalCount: 1 metaAnalysisCount: 0 replicated: false newestStudyYear: 2021 level: 1 references: - id: "1" pmid: "12608926" url: "https://pubmed.ncbi.nlm.nih.gov/12608926/" title: "Indoor air quality, ventilation and health symptoms in schools: an analysis of existing information" authors: "Daisey JM, Angell WJ, Apte MG" year: 2003 journal: "Indoor Air" - id: "2" pmid: "15064163" url: "https://pubmed.ncbi.nlm.nih.gov/15064163/" title: "Phthalate exposure and pulmonary function" authors: "Hoppin JA, Ulmer R, London SJ" year: 2004 journal: "Environmental Health Perspectives" - id: "3" pmid: "34297865" url: "https://pubmed.ncbi.nlm.nih.gov/34297865/" title: "Emissions of soot, PAHs, ultrafine particles, NOx, and other health relevant compounds from stressed burning of candles in indoor air" authors: "Andersen C, Omelekhina Y, Rasmussen BB, et al." year: 2021 journal: "Indoor Air" changelog: - date: "2026-10-22" kind: "correction" summary: "Removed the claim that beeswax candles release negative ions that clean the air, and added a lab study of candle emissions." previously: "Beeswax candles burn clean and actually release negative ions that can help bind particulate matter in the air." why: "We found no study supporting the negative-ion claim. A 2021 chamber study found that all five candle types it tested gave off soot when the flame was disturbed." pmids: - "34297865" --- That "fresh linen" candle or plug-in air freshener isn't cleaning your air. It's adding chemicals to it. Many of the most popular home fragrance products release compounds linked to respiratory irritation, hormone disruption, and cancer risk -- all while making you think your home smells "clean." ## Paraffin Candles Most candles sold today are made from paraffin wax, a petroleum byproduct. A single candle in a well-ventilated room may not reach dangerous levels, but burning multiple candles in a small space with poor ventilation is a different story. Scented paraffin candles are the worst combination: you get both the combustion byproducts of the petroleum wax and whatever synthetic fragrance chemicals are mixed in. ## Plug-In and Spray Air Fresheners Plug-in air fresheners heat a liquid fragrance cocktail continuously, releasing a steady stream of volatile organic compounds (VOCs) into your home. Studies have detected formaldehyde, benzene, toluene, and ethylbenzene in emissions from popular air freshener brands [1]. Spray fresheners do the same in bursts. They don't eliminate odors -- they mask them by flooding your nose with stronger chemicals, or in some cases, by coating your nasal passages with a film that deadens your sense of smell. ## The "Fragrance" Loophole Look at the ingredients on any scented product -- candle, air freshener, dryer sheet, cleaning spray -- and you'll see "fragrance" or "parfum" listed as a single ingredient. Under current regulations, this one word can represent a blend of dozens to hundreds of individual chemicals that manufacturers are not required to disclose. This is a trade secret protection, not a safety measure. Independent testing has found phthalates (endocrine disruptors linked to reduced pulmonary function [2]), synthetic musks, and allergens hidden under the "fragrance" umbrella. You literally cannot know what you're breathing. ## Better Alternatives **Beeswax candles** use one natural wax instead of petroleum paraffin and have a faint honey scent of their own. They are not air cleaners, though. In a lab study of five kinds of pillar candles, every one gave off soot when its flame was disturbed by moving air, and the wax and wick changed how much [3]. We found no good evidence that beeswax releases negative ions that clean the air. Beeswax candles cost more, but they burn longer; keep them out of drafts. **Soy candles** are a middle ground -- cleaner-burning than paraffin, more affordable than beeswax. Look for 100% soy (many "soy" candles are soy-paraffin blends) with cotton or wood wicks and scented only with essential oils. **Essential oil diffusers** (ultrasonic or nebulizing) disperse plant-derived aromatic compounds without combustion. Be mindful that essential oils are potent -- use them sparingly, especially around pets and children. They're not risk-free, but they avoid the petroleum byproducts and synthetic fragrance chemicals. **Or just open a window.** The simplest air freshener is ventilation. Five minutes of cross-ventilation (opening windows on opposite sides of your home) can dramatically improve indoor air quality without adding anything to the air. ## Why This Matters More Than You Think The average person spends about 90% of their time indoors. Indoor air pollution concentrations can be 2 to 5 times higher than outdoor levels, and fragrance products are a major contributor. The chronic, low-level exposure pattern matters -- your body can process occasional exposures, but a plug-in running 24/7 for months creates a continuous chemical burden. The health effects are real but often misattributed. Headaches, nasal congestion, "allergies," and fatigue that people accept as normal life can be driven by fragrance chemicals in their own homes. People who eliminate synthetic fragrance products from their homes frequently report improvements in these symptoms within weeks. The phthalate connection is particularly concerning. These plasticizer chemicals are used to make fragrances last longer, and they've been associated with decreased pulmonary function even at common exposure levels [2]. Because they're endocrine disruptors, they may have effects well below what traditional toxicology would predict as a "safe" dose.