Can Aromatherapy Candles Be Burned Frequently? Are They Harmful to the Human Body?

Whether you can burn aromatherapy candles frequently and whether they are harmful to your health depends on the quality of the candles you purchase and whether you use them correctly. If you choose the wrong candles or use them improperly, it can have adverse effects, especially with long-term use.

I. Overview of Aromatherapy Candles

Aromatherapy candles are made by mixing fragrance oils into melted wax and inserting a wick. Once the wax cools and solidifies, it becomes an aromatherapy candle. These candles can be used in various spaces within your home. Even when not lit, they slowly release fragrance into the air. When lit, they create a warm and cozy atmosphere, making them a popular choice for creating a romantic and soothing ambiance.

Determining whether aromatherapy candles can be burned for an extended period primarily involves evaluating four aspects related to human health: the wick, wax, fragrance oils, and containers.

II. The Wick

1. Types of Wicks: Aromatherapy candle wicks generally come in three types: cotton wicks, wooden wicks, and eco-friendly wicks. Cotton wicks are the most commonly used, and eco-friendly wicks are sometimes referred to as “smokeless wicks.” Wooden wicks, such as those used by brands like Wood Wick, have gained popularity in recent years.
   • Cotton Wicks: Cotton wicks are made of pure cotton and are twisted into a braided form. They come in various thicknesses and densities. Cotton wicks tend to be soft and need a layer of paraffin to stabilize their hardness before use. This prevents them from tilting or burning unevenly during candle use. Cotton wicks are generally suitable for candles with a diameter of less than 10 centimeters and usually do not require trimming to burn evenly.
   • Eco-friendly Wicks: Eco-friendly wicks, often called “smokeless wicks,” are typically a blend of cotton and paper. They have greater hardness compared to cotton wicks. However, they are prone to carbon buildup, which can lead to incomplete combustion, resulting in black smoke and mushrooming. Therefore, they require regular trimming.
   • Wooden Wicks: Wooden wicks are known for producing a gentle crackling sound when burning, creating a cozy atmosphere. They are made by aligning 2 to 3 thin wood pieces, leaving gaps in between to absorb more wax and ensure stable burning. Cherry wood is considered the best material for wooden wicks in imported candles. However, domestically, some use wood with lower density, and the quality depends on the manufacturer’s wood selection and thickness precision.
2. Harmful Effects of Incorrect Wicks:
   • Incomplete Combustion and Harmful Emissions: Incomplete combustion can release harmful particles like PM2.5 and volatile organic compounds (VOCs), which can have a significant impact on respiratory health, especially with frequent use.
   • Uneven Burning: If the wick tilts, it can cause uneven burning, where one side of the candle burns higher than the other. This not only affects aesthetics but also disrupts the candle’s functionality.
   • Burn Interruptions: Wooden wicks are more prone to burn interruptions due to inadequate adhesion, which can be caused by subpar material or manufacturing.
   • Weak or Dim Flames: The quality of the flame can affect your experience, as some may prefer a brighter, stronger flame.
   • Unsightly Craters: Using wicks that are too thin for the container’s diameter can result in unsightly craters in the candle, affecting aesthetics and usability. This issue cannot be resolved using external tools like wick trimmers.

III. The Wax

1. Types of Wax: Aromatherapy candles are primarily made from animal or plant-based waxes. These waxes typically burn cleanly without residue, making them more environmentally friendly and safer for human health. Common plant-based waxes include soy wax, coconut wax, and palm wax. Beeswax is the primary animal-based wax used in candles.
2. The Controversy of Paraffin Wax: The most controversial type of wax is paraffin wax, as it is derived from petroleum. Paraffin wax is categorized into various grades, with food-grade paraffin being considered safe for candles. However, some cheap candles may use industrial-grade paraffin, which may contain impurities. Properly refined food-grade paraffin is considered safe for candles.
3. Risks of Poor-Quality Wax: Poor-quality candles may use inferior wax or excessive amounts of low-quality wax. These candles can release harmful substances when burned, posing risks of carcinogenicity, teratogenicity, and other health concerns, especially in indoor settings.

IV. Fragrance Oils

Many people assume that aromatherapy candles contain essential oils, and some sellers promote this idea, claiming “pure plant essential oil ingredients” and “safe for mothers and babies.” In reality, aside from DIY candles, nearly all commercially available finished candles contain fragrance oils.

1. What Are Fragrance Oils?: Fragrance oils are a blend of various aromatic compounds. Fragrance ingredients fall into several categories:
   • Natural fragrances from essential oils or extracts.
   • Nature-identical ingredients that are chemically synthesized but match natural fragrance components in structure and scent.
   • Synthetic fragrance ingredients created in a laboratory.
2. Safety of Fragrance Oils: Fragrance oils used in candles are typically not the same as essential oils. They are formulated to be safe for burning and are subject to regulations and industry standards. In the absence of specific national standards for aromatherapy candle fragrance oils, industry organizations like the International Fragrance Association (IFRA) and the Research Institute for Fragrance Materials (RIFM) provide guidelines. Reputable candle manufacturers adhere to these standards.

V. Containers

Container safety issues mainly apply to ceramic and glass containers. If these containers are not of high quality and combined with prolonged candle burning, they can be prone to cracking or even shattering, posing safety hazards. This is why many aromatherapy candles recommend extinguishing the candle at least every 4 hours to reduce this risk. Some low-quality metal containers can also become very hot with extended candle use, presenting another safety concern.

VI. Proper Candle Usage

Using aromatherapy candles correctly is essential not only for aesthetics but also for extending their lifespan. The following are some guidelines for proper candle use:

• Trim the wick regularly to maintain even burning and prevent mushrooming.
• Allow the candle to create a full melt pool during each burn to avoid tunneling.
• Avoid burning candles for extended periods (e.g., more than 4 hours at a time).
• Place candles on heat-resistant surfaces, away from flammable materials, drafts, and out of reach of children and pets.
• Follow the manufacturer’s instructions and safety guidelines provided on the candle’s packaging.

In conclusion, whether you can safely burn aromatherapy candles frequently depends on the quality of the candles and how you use them. Choosing high-quality candles, following proper usage guidelines, and being mindful of safety precautions can enhance your experience and minimize potential health risks associated with candle burning.