Candles are popular for enhancing a home’s atmosphere with soft light and appealing scents. However, burning a candle can trigger uncomfortable symptoms for many people. While a true, life-threatening allergy to a candle is rare, adverse reactions and sensitivities are quite common. This guide explores the difference between these reactions, identifies the irritating ingredients, and provides steps for a safer burn.
Understanding the Difference Between Allergy and Sensitivity
A true allergy is an immune system reaction involving the production of Immunoglobulin E (IgE) antibodies. This occurs when the body mistakenly identifies a substance, typically a protein, as a threat. Symptoms of a true allergy can be severe, including hives, swelling, and life-threatening respiratory distress.
A sensitivity, or intolerance, is a non-immune reaction often caused by irritation from chemicals or particulate matter. Candle reactions overwhelmingly fall into this category, causing symptoms like contact dermatitis, watery eyes, sneezing, headaches, and respiratory tract irritation. These effects stem from the irritating nature of the released compounds, not an immune system overreaction.
The low molecular weight chemicals and volatile organic compounds (VOCs) emitted by candles directly stimulate sensory nerve endings in the respiratory tract. This irritation can worsen pre-existing conditions like asthma or environmental allergies. Most adverse candle reactions are therefore a sign of irritation from chemical exposure rather than an IgE-mediated immune response.
Specific Ingredients That Cause Reactions
The primary sources of irritation in conventional candles are the type of wax used and the chemical composition of the fragrance. Most mass-market candles utilize paraffin wax, a byproduct of petroleum refining. When paraffin burns, it releases volatile organic compounds (VOCs) that pollute indoor air quality.
These VOCs include known irritants like toluene and benzene, which are also found in diesel fuel emissions. Exposure to these chemicals is linked to respiratory issues, headaches, and nausea, and they are classified as carcinogens. Burning paraffin wax also produces fine particulate matter, or soot, which can be inhaled and contribute to poor air quality.
Synthetic fragrances are another major culprit, often containing a complex chemical mixture protected under trade secret laws. These fragrances frequently contain phthalates, which are used as solvents and fixatives to help the scent last longer. Phthalates are known endocrine disruptors because they interfere with hormone function in the body.
Certain fragrance components, such as limonene, can react with ambient ozone to form secondary pollutants like formaldehyde. Formaldehyde is a known irritant and carcinogen that causes irritation to the eyes, nose, throat, and skin. Dyes used to color the wax can also be problematic, potentially triggering contact irritation if they touch the skin.
Choosing Safer Candles and Reducing Exposure
Choosing candle alternatives and implementing simple changes can significantly reduce exposure to irritants. The most straightforward swap is avoiding paraffin-based candles in favor of natural waxes. Look for candles made from 100% natural waxes, such as beeswax, coconut wax, or soy wax.
Beeswax tends to be the cleanest-burning option. Soy and coconut waxes are plant-based and typically produce less soot and fewer harmful byproducts than paraffin. When selecting a scented candle, choose those fragranced only with 100% pure essential oils rather than synthetic fragrances. This avoids the complex chemical cocktails and fixatives like phthalates found in many synthetic formulas.
Proper candle care and ventilation are also important to minimize irritation. Always trim the wick to about one-quarter inch before each burn to ensure the flame remains small and steady, which significantly reduces soot production. Burning candles in a well-ventilated area, such as a room with an open window, helps disperse released VOCs and particulate matter. If severe symptoms occur, such as respiratory distress or swelling, stop using the candle immediately and seek medical attention.