Toxic Chemicals in Candles
When we burn candles indoors, we create a confined space in which pollutants can accumulate [1]. Without outdoor air diluting the particles emitted, these toxins can build up in our homes and can be a contributing factor to indoor air pollution [1]. For this reason, it is important to consider the materials a candle is made from.
Today, the primary concerns lie in the wax of the candle and fragrances added to them. Most conventional candles tend to be made with paraffin wax (or a combination containing paraffin) and are often scented with synthetic fragrance formulas, both of which can be problematic from a human health standpoint. Paraffin wax further poses an environmental concern as it is a petroleum-derived products and, therefore, not readily biodegradable.
Thankfully, lead-cored wicks have been banned [2] from being manufactured, sold or imported in the United States since 2003. However, not all countries have this ban, so be wary of products purchased outside of the U.S. unless that country has a similar restriction. It is ideal to look for wicks that are made with natural materials, such as 100% cotton or wood.
Ingredients of Concern
Some ingredients of concern that commonly show up in candles are:
Phthalates – Phthalates are substances frequently utilized in the fragrance formulations of conventionally scented candles. The ingredients list typically provides little to no explanation of what’s inside a scent or where it comes from. Instead, the scent will be listed as “fragrance” or “parfum” which provides no information to the conscious shopper. While listed as a single entity on product labels, “fragrances” can be comprised of many different undisclosed natural substances or synthetic chemicals, and phthalates are a common ingredient of concern hidden under the fragrance umbrella.
Phthalates exhibit endocrine disrupting activity [3][4]. They have been linked to developmental harm, as exposure is associated with precocious puberty [5], preterm birth [6], and negative impacts on the functioning of amino acids during babies’ development in utero [7]. Phthalate exposure is also linked with obesity [8][9] as well as respiratory problems and asthma in children [9][10]. Phthalates are furthermore implicated in reproductive toxicity [11][12], as exposure has been found to negatively impact male fertility and sperm quality [13][14][15]. Lastly, certain phthalates have been linked to an increased risk in developing cancer [16][17][18].
Formaldehyde – Formaldehyde is a volatile organic compound (VOC) that can be released into the air by a number of activities, including burning candles [19]. The International Agency for Research on Cancer has classified formaldehyde as a Group 1 carcinogen, meaning that there is sufficient evidence of carcinogenicity in humans (and animals) [20]. The U.S. EPA [21] and the European Chemicals Agency [22] also echo this concern for formaldehyde’s carcinogenic effects. Formaldehyde exposure is furthermore suspected of mutagenicity (causing genetic defects) [22][23][24]. Acute exposure to formaldehyde is additionally linked to eye irritation and/or damage [21][22][23][24], allergic skin reactions [21][22][23], and can be fatal if inhaled at high concentrations [22][23].
Acetaldehyde – Like formaldehyde, small amounts of acetaldehyde can be released into the air when burning candles, particularly those containing fragrances [25][26]. It is extremely irritating to the eyes and can also irritate the lungs [27][28][29]. Acetaldehyde is also considered to be a probable carcinogen by numerous authoritative agencies [27][28][29][30]. Lastly, acetaldehyde is suspected of causing birth defects [27][28].
Paraffin – Paraffin wax often makes up the wax portion of candles and is derived from petroleum. Like most petroleum products, paraffin is neither clean-burning nor readily biodegradable in the environment. Candles made from paraffin are known to release toxic chemicals, including aforementioned formaldehyde and acetaldehyde, as well as other compounds like toluene and benzene. Benzeneis carcinogenic to humans [31][32] and causes skin and eye irritation [33] and toluene is linked to a myriad of ill effects, including dizziness and developmental toxicity [34][35][36]. Compared with naturally derived wax-base alternatives, paraffin releases more toxic compounds into the ambient environment [37].
Tips for Choosing a Candle
- Shop for certified candles.
- Avoid candles that contain fragrances of an undisclosed composition, often listed as fragrance, parfum, or simply the scent profile of the candle with no accompanying ingredient list (e.g. “pumpkin spice”). Fragranced candles of this nature release more pollutants than unscented candles [38]. Instead search for candles scented with 100% essential oils, being sure to avoid any essential oils to which you are sensitive or allergic. Unscented beeswax candles tend to give off a faint honey scent as well that is completely natural. It should be noted, though, that if you are accustomed to the overwhelming aroma of a synthetically fragranced candle, naturally scented candles will likely feel more subtle in comparison.
- If you ever do use conventional candles, especially scented ones, be sure to properly ventilate the area to lessen its harmful impact.
- Bypass candles made with paraffin to avoid the negative health and environmental impacts of paraffin. Instead, look for beeswax, 100% non-GMO soy, or coconut candles. Make sure the wax base is not a mixture containing paraffin, as paraffin can be blended with natural waxes to keep prices down.
- Look for 100% cotton wicks or wood wicks.
- Candles can create a lovely ambience, but if your main objective is to freshen your home or mask odor, consider switching things up every once and a while by using alternative methods to keep your home smelling great. This can include utilizing essential oils, room sprays (scented with 100% essential oils rather than “fragrance” or “parfum”), or DIY simmer pots using fruit, herbs, and spices.
References
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